Biomedical subjects
Publications and source records attributed to D Niethammer.
Rahnella aquatilis, a rarely encountered member of the family Enterobacteriaceae, was twice isolated from the blood of a pediatric bone marrow transplant recipient. This is the first report of a pediatric case of R. aquatilis bacteremia, and it was probably related to inappropriate handling of a Hickman catheter.
In vivo administration of superantigens leads to activation and subsequent depletion or anergy of T cells expressing defined V beta-T cell receptors (TCR). Superantigens have therefore become intensively studied tools for examining parameters of immunoregulation and they may represent model antigens for pathogenic agents. An HIV-encoded superantigen has for example been implicated in the dramatic loss of helper T cells in AIDS. We investigated the response of V beta 8+ T cells in mice after primary and secondary exposure to the superantigen Staphylococcus Enterotoxin B (SEB).
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In a one year old female infant BCG-vaccinated as a neonate, a large mediastinal mass was found after routine examination. X-ray and CT scan suggested a teratoma. Histology and microbiology, however, revealed the diagnosis of an active tuberculosis. Thus, the tumor was caused by mediastinal BCGitis. To our knowledge this complication of BCG-vaccination has not yet been described.
Cryptosporidium has been found to be a common cause of gastroenteritis during the last years. The natural course of the disease in immunocompromised patients is often met by serious complications. A general therapy recommendation has not been reported so far. We report of a two-year-old boy, who was immunocompromised by a multidrug cytostatic chemotherapy. The patient suffered from a long lasting most severe gastroenteritis, caused by cryptosporidium. There was a good clinical response to spiramycin, a treatment suggested in the literature.
We report the case of a young boy referred to our Department of Nuclear Medicine under the suspicion of a malignant tumor. The leading clinical symptoms were pain in the joints and loss of weight and vitality. Radiographic findings were suggestive of osteogenic sarcoma, but bone scans showed multiple increased tracer depositions along the cortex of femur and tibia, and in the lower and upper jaw. The enrichment pattern was not typical for metastases, but more probably demonstrated the multiple foci of osteomyelitis. This assumption was confirmed by the histological findings, which were diagnosed as primary chronic osteomyelitis. This rare pediatric bone disorder has been described by Giedion et al. The etiology of the disease is unknown, and therapy is discussed controversely in literature.
Nine patients with neuroblastoma stage IV were treated with the murine monoclonal antibody 14.G2a, directed against disialoganglioside GD2. The antibody was injected daily for 5-10 days and the total applied dosage ranged between 100 mg/m2 and 400 mg/m2. The peak serum levels of mAb 14.G2a ranged from 28 micrograms/ml to 61 micrograms/ml. Pharmacokinetic data obtained in three patients indicated that the serum elimination of mAb 14.G2a fits a two-compartment model, with an alpha-half-time (t1/2 alpha) between 0.66 h and 1.98 h and a beta-half-time (t1/2 beta) between 30.13 h and 53.33 h. All patients presented with a human anti-(mouse IgG) antibody response either during or shortly after therapy. Eight patients showed a continuous decrease in complement component C4 during therapy, as well as an initial decrease in C3c and an initial increase in C3a, all suggesting an activation of the complement cascade. Side-effects consisted of allergic reactions like pruritus, exanthema, urticaria and of severe pain, predominantly located in the abdomen and lower extremities, which required the use of continuous intravenous morphine. Four patients additionally developed a transient hypertension and one patient experienced a transient nephrotic syndrome. Three patients were treated in an adjuvant setting and are not evaluable for tumor response. Of the remaining six patients, two had a complete remission, two showed a partial remission, and two patients did not respond to treatment.
A commercially available enzyme immunoassay was used to determine ferritin content and subsequently the loading and release of iron from ferritin in neuroblastoma cells. LS cells were incubated with 59Fe for 24 h, lysed, and the cytoplasmic ferritin was bound to monoclonal antibodies coupled to globules. After determination of the ferritin content the same globules with bound radioactive ferritin were measured in a gamma-counter. To illustrate the applicability of this test system, increased iron loading of cellular ferritin could be demonstrated in cycloheximide-treated cells; furthermore, release of iron was documented after incubation of LS cells with a combination of 6-hydroxydopamine and ascorbate. The assay turned out to be a simple method for determination of changes in 59Fe content of ferritin in neuroblastoma cells.
The interferon-inducible enzyme, 2'-5'-oligoadenylate synthetase, was estimated in healthy donors and in patients before and after subcutaneous application of recombinant interferon beta and gamma. Tests were carried out with lysates of peripheral blood mononuclear cells, using an established radioenzymatic assay, and in serum samples, using a new radioimmunoassay. Both test systems substantially yielded the same results: after a single injection of interferon beta (1-5 x 10(6) IU), 2'-5'-oligoadenylate synthetase increased in a dose-dependent manner reaching maximal catalytic concentrations in most patients after 24-48 hours (leukocytes) and 48-72 hours (serum). In contrast, interferon gamma (2-4 x 10(6) IU) caused only a small induction of 2'-5'-oligoadenylate synthetase. However, daily application of interferon gamma for 7 days led to a distinct time-dependent increase of 2'-5'-oligoadenylate synthetase activity concentration during this observation period. Characteristically, even during daily application, the 2'-5'-oligoadenylate synthetase activity concentration dropped just 48-72 hours after the first injection of interferon beta. The determination of 2'-5'-oligoadenylate synthetase proved to be useful for optimizing and monitoring subcutaneous therapy with interferon. The new radioimmunoassay which allows the determination of this enzyme in serum is superior to other methods used in the past.
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Between 1989 and 1990 nine children with neuroblastoma stage IV (according to Evans) have been treated with high-dose [131I-meta]Iodobenzylguanidine (HD-mIBG). The total HD-mIBG dose administered to each child was at mean 699.3 +/- 111 MBq/kg body weight. Prior to (median 28 days) and after (median 50 days) HD-mIBG treatment a diagnostic scan with [123I-meta]Iodobenzylguanidine ([123I-m]IBG) was performed. Scans performed with HD-mIBG were superior to diagnostic scans for the detection of bone lesions in 8/9 children, for the detection of soft tissue lesions in 4/9 children, and for a more precise diagnosis of the primary tumor in 1 child. In 4 children lesions which were primarily identified in the therapeutic scan could be further observed in posttherapeutical examinations.
As chronic life-threatening diseases, cancer or leukemia in children generates an extreme situation for the family involved that can go on for years. Psychosocial care for all family members by a pediatric oncologist should be integrated into the treatment plan, as this is both helpful and necessary.
BACKGROUND: Within a few months we twice observed the following situation: In each of two different communities, a young child fell ill with meningitis caused by Haemophilus influenzae type B (HIB). One week later, a second case occurred in the same community. Both patients had had no direct contact with each other. But each had an asymptomatic older sibling. These siblings attended the same kindergarten and had close contact with each other. The isolated HIB strains were identical (capsular type b, biotype I, outer membrane protein subtype 1 and lipopolysaccharide serotype 1) and were beta-lactamase-negative. CONCLUSION: Since it must be assumed that the causative HIB strains circulated in the respective kindergartens and were transmitted to the patients by their healthy siblings, a rifampicin chemoprophylaxis was instituted which included all kindergarten children and their younger siblings. Since the current guidelines on chemoprophylaxis in HIB meningitis do not deal with a situation like the one encountered by us, a revision of the present guidelines was proposed and has been implemented in the meantime.
Neuroblastoma cells accumulate ascorbic acid and iron. It was hypothesized that these features could be exploited for sensitizing neuroblastoma cells for therapy in combination with reactive oxygen intermediates. In the present study the effects of 6-hydroxydopamine (6-OHDA) and H2O2 on metabolic parameters critical for cell survival were investigated in cells with low and high ferritin content in the presence and absence of ascorbate. Human neuroblastoma SK-N-SH cells were pretreated with 100 microM FeSO4 and 10 microM desferrioxamine, respectively, for 24 h yielding cells with different ferritin contents. The effects of 6-OHDA and H2O2 (25 microM-250 microM) in the absence and presence of 1 mM ascorbic acid on DNA strand break formation, activation of poly(ADP-ribose) polymerase, and finally decrease in NAD+ and ATP concentration were investigated. All these parameters were influenced by 6-OHDA and H2O2 in a concentration-dependent manner in a similar way. The effects were most pronounced in ferritin-rich cells and in the presence of ascorbic acid. Using isolated CCC PM2 DNA, 6-OHDA and ascorbic acid caused strand breaks that were prevented in the presence of mannitol or desferrithiocine. H2O2-mediated strand breaks were observed only in the presence of ascorbic acid. Based on these data and data published by others a model explaining the deleterious effects of ascorbic acid on neuroblastoma cells is presented. It is suggested that continuous application of a high dosage of ascorbic acid might be a useful approach in neuroblastoma therapy.
Between April 1985 and March 1987 130 children and adolescents up to 18 years of age with first relapse of acute lymphoblastic leukemia (ALL) were registered on the stratified and randomized multicentric trial ALL-REZ BFM 85 designed for patients pretreated with intensive front-line therapies. Stratification criteria were time and site of relapse: bone marrow (BM) relapse on or up to 6 months after stopping front-line therapy (group A), BM relapse beyond 6 months after therapy (group B), and isolated extramedullary relapse at any time (group C). Treatment consisted of alternating courses of polychemotherapy including randomly administered high- or intermediate-dose methotrexate (HDMTX:12 g/m2 as 4-hour infusion; IDMTX: 1 g/m2 as 36-hour infusion). During maintenance therapy the patients received daily oral thioguanine and biweekly intravenous (IV) MTX. The overall second complete remission (CR) rate was 92% (groups A, B, and C: 88%, 92%, and 100%), and the probability of event-free survival (EFS) at 6 years is 0.31 +/- 0.04 (groups A, B, and C: 0.18 +/- 0.05, 0.30 +/- 0.07, and 0.72 +/- 0.11). HDMTX did not prove to be superior to IDMTX, which led to premature stopping of randomization. Risk factor analyses showed early relapse, particularly BM relapse within 18 months, and T-cell phenotype to be independent predictors of poor outcome. The incidence of central nervous system (CNS) relapses following BM relapse was 19%, indicating that reprophylaxis to the CNS with IV/intrathecal (IT) MTX was insufficient. For 17 children who received bone marrow transplantation in second CR from HLA-compatible siblings the EFS was 0.53 +/- 0.12 at 5 years. Their outcome was not influenced by the above-mentioned risk factors. With the proposed treatment regimen long-lasting second remissions can be achieved in about one third of patients even after intensive front-line treatment.
Together with 2-5A synthetase and ribonuclease L, 2-5A phosphodiesterase belongs to the 2-5A system, which plays an important role in the action of interferon. Analytical capillary isotachophoresis was used for the determination of 2-5A phosphodiesterase activity. Enzyme assay was optimized using snake venom phosphodiesterase as a source of 2-5A phosphodiesterase activity. The 2-5A trimer core was used as a substrate. Enzyme activity was determined in time- and concentration-dependent reactions. In addition, 2-5A phosphodiesterase activity was determined in lysates of mononuclear blood cells.
From 1984 to 1989, 47 children with relapsed, refractory, and/or metastasized neuroblastoma were treated with 131I-metaiodobenzylguanidine (mIBG) in several different treatment combinations. At initial diagnosis, 36 children had Evans stage IV and 11 stage III disease. In 16 of the 47 children, tumor recurred after complete remission prior to mIBG treatment, 26 of 47 progressed from residual or nonresponding tumor, and in 5 of 47 tumor progression during chemotherapy was observed. Altogether the children were treated with a total of 112 courses (range 1-6) with a mean dosage of 8.9 +/- 6.7 mCi/kg body weight/treatment course. Total dose was 283.2 +/- 203.7 mCi for stage III and 388.9 +/- 218.6 mCi for stage IV. Nine of 47 children reached a complete or a very good partial remission (CR and VGPR) from mIBG treatment alone, 13 of 47 achieved partial remission (PR). In an early analysis, 10 patients treated with mIBG in the neuroblastoma trial NB 85 of the German Society of Pediatric Oncology showed no significant difference in survival time compared with 30 conventionally treated children. However, the recent therapy series has been done with higher doses of mIBG, and during improved therapeutic scanning many more bone lesions could be detected than during earlier diagnostic scanning. We conclude that mIBG treatment has not yet fulfilled the expectations for it but still seems for certain indications to be a promising tool to treat neuroblastoma in the future. Moreover, the frontier of neuroblastoma detection is still advancing.
Since impaired growth may occur as a long--term consequence in children treated with BMT this aspect of development needs particular attention for various reasons. Primarily, in each affected child parameters relevant for the evaluation of growth need to be documented regularly from the beginning in a prospective mode. In addition, treatment protocols should contain elements of a standardized follow-up for the documentation and evaluation of the endocrine, the nutritional and the emotional situation of the patient. This will eventually allow us to define--and hopefully avoid--adverse elements within complex treatment modalities--including BMT--for various malignant diseases. Thus it will be possible to develop a rational approach for the therapy of persistent adverse events following attempts of treatment primarily directed to ensure survival.