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B Kremens

Publications and source records attributed to B Kremens.

At least 55 records · Page 3Linked to original sources
PubMed1993

Rapid detection of engraftment using T cell receptor gene polymorphism after allogeneic bone marrow transplantation in an alloimmunized child with severe aplastic anemia.

A severely alloimmunized boy with aplastic anemia received an HLA-identical BMT from his brother. Despite intensive immunosuppression and large marrow dose, peripheral signs of engraftment occurred only late under G-CSF treatment. With leukocyte counts of < 0.5 x 10(9)/l, chimerism could be proven not only by oligonucleotide fingerprinting but also within 48 h by analysis of polymorphism in the TCR gene family. This rapid and sensitive method to detect engraftment before it became quantitatively evident was important for the clinical management of the patient, obviating the need to search for an alternative marrow donor.

Anemia, Aplastic↗
PubMed1991

[Experiences with a modified implantation technique of Port-A-Cath systems as continuous venous access in infants and children].

Since April 1987 we implanted the Port-A-Cath infusion system in 60 children in the age of 2 months to 16 years (median: 4.3 years). We only used the adult system (Pharmacia). By one right side infraclavicular incision the silicon catheter was implanted into the jugular vein and also the port was fixed on the pectoral fascia. We saw one severe complication as a port perforation through the skin. 1.6% was the very low rate of complications which appeared in the median of the port using time of 168.5 days.

Adolescent↗
PubMed1990

Diffuse sclerosing variant of papillary thyroid carcinoma. S-100 protein immunocytochemistry and prognosis.

The recently published second edition of the WHO classification of thyroid tumours describes the diffuse sclerosing papillary carcinoma (DSPC) as a specific variant of papillary thyroid cancer (PC). Besides several histological hallmarks, this rare tumour is characterized by its occurrence in young individuals and is thought to have a less favourable prognosis than PC in general. The observations on two examples of this tumour presented herein, however, are at variance at this assumption. The neoplasms occurred in a 10 year old girl and a 34 year old woman. Each time, diffuse involvement of both thyroid lobes and bilateral cervical lymphadenopathy were seen. In one case, the carcinoma extended into the cervical soft tissue. Follow-up disclosed both patients to be without evidence of disease 2 and 13 years, respectively, after thyroid surgery. Immunocytochemically, both thyroid primaries as well as 7 other cases of DSPC reported in the literature showed dense accumulations of S-100 protein positive dendritic/Langerhans cells. Such infiltrations have been demonstrated to be correlated with a benign clinical course of PC. It is thus suggested that DSPC behaves similarly or even less aggressively than PC in general, at least if prominent Langerhans cell infiltration is present.

Adult↗
PubMed1990

[HCG producing malignant teratoma of the testis: a rare cause of precocious isosexual maturation in boys].

Human chorionic gonadotropin (HCG) from a testicular tumor histologically diagnosed from its metastases to be a malignant teratoma induced elevated testosterone levels and subsequent precocious isosexual development in a 12-year-old boy. The endocrinologic consequences of long term ectopic HCG production in the prepubertal male are discussed. The case report illustrates the value of HCG serum levels as a marker for tumor activity.

Child↗
PubMed1990

[Cross-sectional study of elementary school children for assessing suspected effects of regional hemato-toxic environmental pollutants].

To investigate the suspicion of an increased incidence of leukopenia in school children living in the more industrialised northern region of the city of Essen, blood counts of these children were compared to those of pupils from the southern region in a two-phased study. In 469 1st and 2nd grade children, neither the mean leukocyte count nor the number of individual abnormal results differ between the two regional groups. A difference in the mean hemoglobin value found in the first series of investigations could not be reproduced in a control study of 255 children, the analysis of the data pointing to a methodological reason for the difference. Feasibility, planning and interpretation of results of such a cross-sectional study are discussed.

Air Pollutants↗
PubMed1990

[Evaluation of a modified immunomagnetic procedure for the purging of neuroblastoma cells from bone marrow].

The immunomagnetic depletion method for removing tumor cells from bone marrow, previously refined using a Burkitt lymphoma model, was tested with neuroblastoma cells. The efficiency of depletion was quantified by immunofluorescence with a detection limit of 3.3 log of cell depletion corresponding to the elimination of 99.84% of an initial tumor cell content of 10%. A panel of five monoclonal antibodies (UJ13A; UJ127.11; UJ181.4; alpha-Thy1; H11) purged 2.8 log of SKNBE and LAN-1 cells, while two of these antibodies as single agents allowed only for a 1.7 log (UJ13A) and a 1.7 to 2.0 log (alpha-Thy1) depletion. This underlines the advantage of an antibody panel for neuroblastoma purging. The new antibody S-L 11.14, an IgG2a against small cell lung cancer which recognizes 90% of neuroblastoma cells purged 2.8 log.

Antibodies, Monoclonal↗
PubMed1989

Immunological detection of neuroblastoma cells in bone marrow harvested for autologous transplantation.

In about 50% of patients with stage IV neuroblastoma, micrometastases are present in the bone marrow when it is harvested for an autograft to follow induction therapy, and the risk of graft contamination by neuroblastoma cells has been the rationale for the use of a purging procedure. However, bone marrow metastases are detected with trephine biopsies which only explore the sites biopsied and do not reflect potential contamination of the pooled marrow harvested for autograft. A two-colour fluorochrome labelling method is described which permits as few as 1 neuroblastoma cell in 100,000 normal bone marrow cells from the autograft to be detected. Three monoclonal antibodies (UJ13A, H11 and 11.14) which react with neuroblastoma cells are used as single reagent in combination with a fourth anti-panleucocyte antibody. This method requires only 2 h for the analysis of three million marrow cells from the autograft, and is more effective than alkaline phosphatase staining with the same monoclonal antibodies. Results were compared with conventional techniques (four biopsies and four aspirates) carried out at the same time in 34 consecutive patients. Of 18 cases with negative aspirates and biopsies, neuroblastoma cells were detected in two autografts by the immunological method. Of 16 cases with positive aspirates and/or biopsies, 10 autografts were positive by the immunological method and six were negative. Thus, marrow micrometastases were detected in 16 of the 34 patients, but the autograft contained malignant cells in only 12 of these patients and the immunological analysis demonstrated that the use of a purging procedure allowed the elimination of neuroblastoma cells from the autograft before its reinjection to the patients.

Antibodies, Monoclonal↗
PubMed1988

S-L 11.14: a monoclonal antibody recognizing neuroectodermal tumors with possible value for bone marrow purging before autograft.

A new monoclonal antibody (S-L 11.14) raised against small cell lung cancer reacted with all but one neuroblastoma tumor cell sample tested and was relatively specific for such cells within the bone marrow. The ability of S-L 11.14 to eliminate neuroblastoma cells from the bone marrow with an immunomagnetic purging method was evaluated in an experimental model using the LAN.1 and SKNBE neuroblastoma cell lines as targets. Residual malignant cells after the purging procedure were quantified by the Hoechst staining method. The use of S-L 11.14 as a single reagent resulted in a 3-log elimination of malignant cells, a depletion equal to that obtained with a cocktail of five monoclonal antibodies currently used in clinical trials. The addition of the S-L 11.14 antibody to this cocktail did not enhance depletion.

Antibodies, Monoclonal↗
PubMed1988

[Metastatic neuroblastoma with secondary hypersecretion of vasoactive intestinal peptide].

A 18-month-old boy with stage 4 neuroblastoma needed intensive care because of prerenal acute renal failure related to an intractable watery diarrhoea syndrome occurring 10 months after the diagnosis of the primary tumor. This diarrhoea was in relation with a late hyperproduction of vasoactive intestinal peptide by the relapsing neuroblastoma itself and stopped with intravenous somatostatin administration.

Diarrhea, Infantile↗
PubMed1987

Definition of response and remission in children over one year of age with advanced neuroblastoma: proposition for a scoring system.

A two-step evaluation system is proposed to analyze the results of therapy for stage IV neuroblastoma in children over 1 year of age. Since most protocols consist of first-line chemotherapy followed by surgery and often high-dose chemotherapy with bone marrow rescue, "response" should assess the effect of chemotherapy alone and "remission" indicate the status after an attempt to remove the primary tumor. A scoring system is proposed for both steps. The comparability of different studies depends on the use of such common criteria to define patient groups and treatment results.

Adolescent↗
PubMed1987

[Neuroblastoma in 1987 (1)].

Neuroblastoma is a rare tumour, yet the most frequent one in children below the age of five years. It can be considered as a model in several regards. It is a unique clinical modal with a particular form in infants below one year of age, who present a better prognosis, whereas the disseminated form in children over one year of age has been almost always fatal until recently. It shows the necessity of the interdisciplinary approach in paediatric oncology and some of its recent progress. It is a unique biological model to study the problems of spontaneous maturation, immunological control of tumours, the impact of genetics and of techniques which may completely change cancer therapy ten years from now. Finally, neuroblastoma is a model concerning possible screening and prevention of a childhood malignancy, which involves the cost/efficacy aspect.

Age Factors↗
PubMed1987

[Focus on neuroblastoma in 1987. 2: Treatment].

Chemotherapy and surgery are both important for the treatment of neuroblastoma. The therapeutic indications depend upon the anatomic form of the tumor, but the quality of the surgical resection is most important. In metastatic neuroblastoma, the prognosis has recently been improved with massive chemotherapy, total body irradiation and bone marrow transplantation. Neuroblastoma occurring before one year of age has a particular position, because of its very good prognosis (90% survivals) but with frequent sequelae due to spinal cord compression. Possible improvements stemming from immunology, genetics and mass screening are discussed.

Bone Marrow Transplantation↗
PubMed1985

[Progressive-septic granulomatosis: improved prognosis with early diagnosis and targeted therapy. Report of 5 cases].

The clinical and laboratory findings in chronic granulomatous disease are illustrated by five case reports. Biochemical studies of the neutrophil bactericidal defect have revealed several molecular forms of the disease. Specific therapeutic action is nowadays possible, after early diagnosis of the condition by nitroblue-tetrazolium test and chemiluminescence. Infections are treated using antibiotics and antimycotics which penetrate well into granulocytes; additional surgical intervention or granulocyte transfusion may be necessary. Prolonged infection-free periods are achieved under prophylactic sulfamethoxazole/trimethoprim therapy, promising an improved prognostic outlook for patients with chronic granulomatous disease.

Adult↗
PubMed1982

Thanatophoric dysplasia with cloverleaf-skull. Case report and review of the literature.

The radiologic and morphologic features of thanatophoric dysplasia with cloverleaf-skull could be demonstrated in a neonate who died from asphyxia shortly after birth. Occipital bone hemangiomatosis, a typical histomorphologic finding in cloverleaf-skull, is reported for the first time in a thanatophoric dwarf. Our investigations and the discussion of 26 observations of thanatophoric dysplasia with cloverleaf-skull reported since 1967 do not yet allow complete understanding of the pathogenetic relationship of both malformations. They serve, however, to elucidate some crucial unanswered questions which it is suggested should be studied in future observations of thanatophoric dysplasia with cloverleaf-skull.

Dwarfism↗
PubMedDate not supplied

Microarray-analysis: a new approach to study the molecular mechanisms of thermo-chemotherapy.

BACKGROUND: Experimental studies for the treatment of relapsed neuroblastoma include the use of hyperthermia in combination with chemotherapeutic drugs. Cytotoxic effects of alkylants and platinum compounds on tumor cells can be enhanced by hyperthermia in various in vitro models. However, the underlying molecular mechanisms are still largely unknown. METHOD: In this study, we used microarray-analysis as a new biological approach to gain insight into the pharmacogenomics and possible target genes of thermochemotherapy. As a model, LAN 1 neuroblastoma cells were treated for 1 h with low doses of cisplatin alone, with simultaneous heating to 42 degrees C or with hyperthermia alone. Gene expression was analyzed at five time points 0 to 24 h after treatment using U95Av2 oligonucleotide arrays (Affymetrix Inc). Significant changes of gene expression levels were calculated by similarity metrices and Pearson correlation. RESULTS: Only a few genes (n = 23) demonstrated altered expression following treatment of LAN 1 cells with cisplatin alone. Hyperthermia alone resulted in significant expression changes of 136 genes in comparison to untreated control cells. Combination therapy of cisplatin and hyperthermia resulted in expression changes of 251 genes, interestingly including 131 genes with unchanged expression under treatment with either cisplatin or hyperthermia alone. Significant changes of expression levels could be annotated to genes involved in heat shock response, protein degradation and apoptosis. These results are now being validated on mRNA- and protein levels by RT-PCR and Western Blot analysis. CONCLUSION: Microarray-Analysis is a suitable new approach for the identification of target genes, which might play an important role for the synergistic effect of hyperthermia and chemotherapy in tumor cells.

Antineoplastic Agents↗
PubMedDate not supplied

The role of chemotherapy in the treatment of children with neuroblastoma stage IV: the GPO (German Pediatric Oncology Society) experience.

340 consecutive patients with neuroblastoma stage IV were analyzed for the possible impact of chemotherapy on general condition, remission status, event free survival and survival. The children entered the trials NB 79, NB 82 and NB 85 of the German Pediatric Oncology Society (GPO). The patients did benefit from chemotherapy by considerable improvement of the general condition, by achievement of 30-40% complete and 60-70% partial remissions. The event free survival (EFS) rate 5-8 years after diagnosis was 13% for all 299 protocol patients, the survival (S) rate 10%. The median/mean EFS time were 11.6/23.8 months, the median/mean S time 17.0/29.4 months. The use of response rates as early predictors for long term survival is challenged. Addition of PCVm (cisplatinum, cyclophosphamide, Vm 26) to ACVD (adriamycine, cyclophosphamide, vincristine, dacarbazine) in trial NB 82 resulted in an improvement of the long term EFS rate from 5% to 18% (S rates 7----21%). The introduction of IVp (ifosfamide, VP16) and increase of doses (cisplatinum, Vm 26) did not further improve the results. Maintenance therapy (NB 82) revealed a positive influence on the outcome. Shorter intervals for realization of chemotherapy were associated with a trend for better EFS (NB 85). Although the group of children with bone marrow transplantation showed better EFS and S data compared to the unselected chemotherapy group, the advantage was less clear if matched pairs (remission status at the time of BMT) were compared.(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Combined Chemotherapy Protocols↗