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D Weber

Publications and source records attributed to D Weber.

At least 91 records · Page 5Linked to original sources
PubMed1997

A synthetic model for microsurgical training: a surgical contribution to reduce the number of animal experiments.

Microsurgery has grown to be an essential technique in pediatric surgery. Thus, there is an increasing need for basic training and skills maintenance, which require a continuous laboratory training. As an alternative to microsurgical exercises on living animals, a model including a simulation vein, artery and nerve is being introduced. It provides an opportunity to practice microsurgical technique with optimal availability at any time at fairly low cost. Its potentials and limits in the training of microsurgical dissection, anastomosis and quality control are being compared to experiments on anesthetized animals. Although a few exercises on living animals are mandatory to close the gap between the laboratory and the patient, a synthetic model is a valuable tool in microsurgical training and helps to reduce animal experiments.

Anastomosis, Surgical↗
PubMed1997

Translational regulation of the human cytomegalovirus pp28 (UL99) late gene.

The pp28 (UL99) gene of human cytomegalovirus is expressed as a true late gene, in that DNA synthesis is absolutely required for mRNA expression. Our previous studies demonstrated that pp28 promoter sequences from position -40 to +106 are sufficient for late gene expression in the context of the viral genome (C. P. Kohler, J. A. Kerry, M. Carter, V. P. Muzithras, T. R. Jones, and R. M. Stenberg, J. Virol. 68:6589-6597, 1994). To extend these studies, we have examined the sequences in the downstream leader region of the pp28 gene for their role in late gene expression. Deletion of sequences from position -6 to +46 (deltaSS) results in a threefold increase in gene expression in transient assays. In contrast, deletion of sequences from position +46 to +88 (deltaA) has little effect on gene expression. These results indicate that the sequences from position -6 to +46 may repress gene expression. To further analyze this region, site-directed mutagenesis was performed. Mutation of residues from either position +1 to +6 (SS1) or position +12 to +17 (SS2) duplicated the effect of the deltaSS deletion mutant, indicating that sequences from position +1 to +17 were important for the inhibitory effect. To assess the biological significance of these events, a recombinant virus construct containing the deltaSS mutant promoter regulating expression of the chloramphenicol acetyltransferase (CAT) reporter gene was generated. Analysis of this virus (RV delta SSCAT) revealed that deletion of sequences from position -6 to +46 does not alter the kinetic class of this promoter. However, the ratio of CAT protein to CAT mRNA levels in RV delta SSCAT-infected cells was 8- to 12-fold higher than that observed in the parental RV24/26CAT-infected cells. These results imply that the leader sequences within the pp28 gene can regulate the translation of this late gene.

Base Sequence↗
PubMed1997

Phase I trial of cyclosporine-induced autologous graft-versus-host disease in patients with multiple myeloma undergoing high-dose chemotherapy with autologous stem-cell rescue.

PURPOSE: To determine the feasibility and toxicity of inducing autologous graft-versus-host disease (GVHD) with cyclosporine in patients with multiple myeloma undergoing autologous stem-cell transplantation. PATIENTS AND METHODS: Fourteen multiple myeloma patients with a median age of 50 years (range, 41 to 63) were enrolled. The median time from diagnosis to transplant was 651 days (range, 229 to 3,353). Ten patients had primary refractory disease, two were in first remission, and two were responsive to salvage therapy. The preparative regimen consisted of thiotepa, busulfan, and cyclophosphamide. Cyclosporine was administered daily for 28 days after the stem-cell infusion, and the dose was adjusted to maintain whole-blood cyclosporine levels between 50 and 150 ng/dL in the first seven patients (low-level group) and between 150 and 300 ng/dL in the other seven patients (high-level group). RESULTS: All patients achieved neutrophil engraftment a median of 11 days after transplant. Four patients developed > or = grade 2 hepatic toxicity, six developed > or = grade 2 nephrotoxicity, and four developed reversible cardiac toxicity. Only one treatment-related death occurred. Cyclosporine was withheld in seven patients for a median of 6 days because of renal and/or liver dysfunction. One patient developed clinical skin GVHD, which responded to corticosteroid therapy. Six patients developed histologic evidence of GVHD without clinical signs of GVHD (subclinical GVHD). The incidence of clinical and subclinical GVHD was similar in both cyclosporine groups. Three of 11 patients assessable for response achieved remissions. Three patients experienced disease progression 80, 160, and 354 days after transplant. Ten patients are alive without progression between 56 and 444 days after transplant. CONCLUSION: Induction of autologous GVHD by posttransplant cyclosporine is feasible and well tolerated in patients with multiple myeloma.

Adult↗
PubMed1997

Another dimension of patient-centered care delivery: understanding the nature of demand.

In designing effective and efficient care delivery systems, health care practitioners should address two major perspectives to patient-focused care--the micro approach, relating to the transaction between providers and health care consumers, and the macro approach, which focuses on understanding the nature of demand, as groups of consumers collectively select and use health care services. By better understanding the nature of demand, health care providers hold the key to designing more effective delivery systems and also the power to manage the demand for services, which may result in highly efficient care delivery.

Community Participation↗
PubMed1996

Exclusion of linkage between RET and neuronal intestinal dysplasia type B.

Neuronal Intestinal Dysplasia type B (NID B) is a complex alteration of the enteric nervous system belonging to the group of intestinal dysganglionoses which may involve rectum, colon, and small intestine. Second only to Hirschsprung disease (HSCR), NID B is one of the most frequent causes of chronic constipation and pseudo-obstructive intestinal dysmotility. Since NID B is often associated with HSCR and point mutations in the RET proto-oncogene have been identified in HSCR patients, we analyzed two NID B pedigrees to investigate if RET mutations might cause also the NID B phenotype. Linkage analysis demonstrated that the NID B locus is not linked to RET in the pedigrees analyzed. Further genetic analyses will possibly improve the understanding of the cause and facilitate diagnostic procedures in NID B.

Drosophila Proteins↗
PubMed1996

Occupational stress and strain of female students: results of physiological, behavioral, and psychological monitoring.

This study of 50 female students (mean age 23) investigated the level of acute and chronic subjective stress, objective strain of everyday university life, and behavior (time budget during a normal day). Physiological parameters, behavioral activities, and psychological parameters were assessed simultaneously both while at the university and at home using a special ambulatory monitoring device capable of storing 23-h records. Comparison between typical study (seminar, lecture) and leisure activities (resting, conversation, etc.) revealed lower heart rate variability during university-related activities, indicative of increased mental load. Physical activity was higher during leisure activities, but heart rate was even higher during study time. Students rated leisure activities to be more enjoyable but less exciting or arousing than studies. Two-factorial MANOVAs with the factors "stay' (at the university, at home) and "chronically stressed by studies', a rating made one week before the monitoring (stressed versus non-stressed students), showed significantly higher heart rates for the chronically stressed students, particularly while at the university as opposed to at home. These students also showed decreased heart rate variability as compared to the non-stressed students, indicating greater mental workload. No differences between the groups were found in socioeconomic variables and personality traits (neuroticism, extraversion, achievement motivation). The results are discussed in the context of the stress concept.

Adult↗
PubMed1996

HyperCVAD for VAD-resistant multiple myeloma.

More effective and safer regimens are needed for patients who have advanced multiple myeloma resistant to or relapsing despite prior treatment with alkylating agents and VAD. We treated 58 such patients using the combination of twice daily cyclophosphamide (total dose 1.8 g/m2) and VAD (hyperCVAD). Treatment was given to outpatients followed by G-CSF at 5 microgram/kg/d until granulocyte recovery. Twenty-three patients responded (40%), with a median duration of granulocyte depression to less than 500/microliter of 4 days and a mortality rate of 2%. The median survival time for all patients was 15 months, and the median remission time of responding patients was 8 months. Patients who had low LDH, low B2M, or primary resistant disease lived significantly longer than patients without these features. The combination of fractionated cyclophosphamide and VAD provided an effective and safe rescue treatment for many patients who had advanced myeloma resistant to standard therapies.

Adult↗
PubMed1996

Deep posterior knee pain caused by a ganglion of the popliteus tendon--a case report.

The most common causes of posterior and posterolateral knee pain (besides referred pain) are knee joint effusions, tendinitis of the hamstring tendons, Baker cyst (semi-membranous cyst), bursitis, meniscal pathologies such as tears and ganglions and lesions of the anterior cruciate ligament. Less common causes include popliteus and gastrocnemius tendinitis, arthrofibrosis after trauma, posterior cruciate ligament sprains, deep venous thrombosis and/or irritations of the common peroneal nerve. We present one patient with posterolateral knee pain after a minor contusion. Magnetic resonance imaging revealed a degenerated posterior horn of the lateral meniscus and a somewhat unclear polypoid structure in the intercondylar region. As the posterior component of the pain persisted even after an arthroscopic partial meniscectomy, an operative revision was performed. A small ganglion of the sheath of the popliteus tendon was found and excised. The patient was immediately relieved of his pain after this procedure. To our knowledge this is the first report concerning a ganglion of the sheath of the popliteus tendon causing posterior knee pain. A similar pathology of the popliteus tendon has been described earlier but at a different localisation (in the hiatus), simulating a parameniscal cyst.

Adult↗
PubMed1996

Avoidance of transection of the palmar cutaneous branch of the median nerve in carpal tunnel release.

The course of the palmar cutaneous branch of the median nerve (PCBMN) was studied in 25 fresh cadaveric upper extremities in order to identify its relation to local structures and commonly used incisions for carpal tunnel release. The PCBMN was found to closely underlie the thenar crease (average, 0-2 mm radial to crease; range, 6 mm ulnar to 6 mm radial to thenar crease), suggesting that an incision fashioned in the thenar crease would lead to frequent PCBMN injury. The PCBMN was also found to cross the axis of the ring finger when the axis was determined with the finger flexed into the palm. The axis of the ring finger, as drawn with the ring finger extended, projected in a more ulnar direction. The PCBMN was an average of 9 mm radial to this projection (range, 1-16 mm). An analysis of 100 human volunteer hands demonstrated that the deepest point between the thenar and hypothenar eminencies was a constant landmark in the proximal palm (interthenar depression). The PCBMN traveled an average of 5 mm radial to the interthenar depression (range, 0-12 mm radial). Thenar crease anatomy and ring finger projection were highly variable both in absolute location and configuration, providing a poor basis for incision placement. An incision placed approximately 5 mm ulnar to the interthenar depression, extending in the direction of the third web space, will decrease the incidence of injury to the PCBMN.

Cadaver↗
PubMed1996

Titanium implant for the osteosynthesis of massive allograft reconstruction to improve follow-up by magnetic resonance imaging.

In twelve patients with local aggressive or malignant bone tumors allograft reconstruction after limb sparing procedures were performed using titanium implants for osteosynthesis. In eleven of these patients magnetic resonance imaging studies could be completed. Distortions of the images were limited to the vicinity of the implants and did not preclude detailed analysis of the gross anatomy and of fine articular structures involving and adjacent to the allografts used. Titanium implants therefore can be recommended whenever magnetic resonance imaging can be anticipated to be of importance for follow-up studies, such as after limb saving procedures for malignant musculoskeletal tumors. Aspects of high interest and importance in such cases include early recognition of local recurrence, bone fusion and healing of soft tissue structures, incorporation of allografts, and viability of cartilage.

Adolescent↗
PubMed1995

[Computer-supported patient history: a workplace analysis].

Since 1991, an extensive computer network has been developed and implemented at the Cantonal Hospital of Lucerne. The medical applications include computer aided management of patient charts, medical correspondence, and compilation of diagnosis statistics according to the ICD-9 code. In 1992, the system was introduced as a pilot project in the departments of pediatrics and pediatric surgery of the Lucerne Children's Hospital. This new system has been prospectively evaluated using a workplace analysis. The time taken to complete patient charts and surgical reports was recorded for 14 days before and after the introduction of the computerized system. This analysis was performed for both physicians and secretarial staff. The time delay between the discharge of the patient and the mailing of the discharge letter to the family doctor was also recorded. By conventional means, the average time for the physician to generate a patient chart (26 minutes, n = 119) was slightly lower than the time needed with the computer system (28 minutes, n = 177). However, for a discharge letter, the time needed by the physician was reduced by one third with the computer system and by more than one half for the secretarial staff (32 and 66 minutes conventionally; 22 and 24 minutes respectively with the computer system; p < 0.0001). The time required for the generation of surgical reports was reduced from 17 to 13 minutes per patient and the processing time by secretaries from 37 to 14 minutes. The time delay between the discharge of the patient and the mailing of the discharge letter was reduced by 50% from 7.6 to 3.9 days.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation Studies as Topic↗
PubMed1995

Light-heavy chain deposition disease progressing to multiple myeloma.

Light chain deposition disease (LCDD) and light and heavy chain deposition disease (LHCDD) are rare clinical entities that have been associated with multiple myeloma, with monoclonal gammopathy of unknown significance (MGUS), or without any detectable protein abnormality. Renal failure is common, the diagnosis is difficult and prolonged survival is rare. The first patient with LHCDD and MGUS who progressed to multiple myeloma after 11 years is presented. A rising level of monoclonal IgA immunoglobulin, bone marrow plasmacytosis, and the presence of multiple bone marrow lesions on magnetic resonance imaging provided the first evidence of disease evolution. When management of serious complications permits a long survival, some patients with LCDD or LHCDD will develop multiple myeloma.

Basement Membrane↗
PubMed1995

Variables influencing the Thrombostat 4000: recommended standardization.

The in vitro bleeding test (IVBT) (Thrombostat 4000) was performed on blood samples from healthy blood donors using a "preliminary standard test." Only one factor of the test procedure was changed each time. We found the following parameters to have a significant influence on the test results: time interval between sampling and testing, diameter of the filter's aperture, capillary diameter, aggregating agents and their concentration, temperature of the blood and cartridges, method of drying the capillaries, the aspiration pressure, and the hematocrit of the blood sample. According to our data, we propose a standard IVBT for routine application and modifications for special diagnostic use.

Adenosine Diphosphate↗