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Biomedical subjects

A Reiter

Publications and source records attributed to A Reiter.

At least 145 records · Page 8Linked to original sources
PubMed1993

[Monitoring neuromuscular function: capnography versus relaxometry].

OBJECTIVE: A notch ("curare cleft") in the plateau phase of the capnogram of the ventilated patient has been presumed to be a typical early sign of the fading effect of muscle relaxants on the diaphragm. For that reason a prospective study was done to investigate whether capnography can be used diagnostically to indicate the fading effect of vecuronium confirmed by peripheral relaxometry. METHODS: Twenty-five consecutive patients who received inhalation anaesthesia with isoflurane, N2O/O2, and vecuronium during elective neurosurgical procedures were studied. Whenever intraoperative "curare clefts" appeared in the capnogram, diaphragm activity was measured and a simultaneous relaxogram of the adductor pollicis muscle was recorded. After every such event, vecuronium was readministered for complete relaxation. RESULTS: A deformation of the capnogram was registered in 17/25 patients and in all instances (51/51) was caused by diaphragm activity. The deformation disappeared after renewed relaxation and was therefore a reliable indicator of spontaneous breathing. However, it did not correlate with the degree of relaxation of peripheral muscles, because diaphragm activity was present during all degrees of peripheral relaxation, but could also be absent even after complete recovery of neuromuscular transmission. CONCLUSION: Capnography is therefore not a reliable method to indicate the fading effect of muscle relaxants.

Anesthesia, Inhalation↗
PubMed1993

Detection and clinical relevance of genetic abnormalities in pediatric acute lymphoblastic leukemia: a comparison between cytogenetic and polymerase chain reaction analyses.

The E2A/PBX1 and the BCR/ABL fusion genes result from the t(1;19)(q23;p13) and the t(9;22)(q34;q11), respectively, and encode oncoproteins which are thought to play an important role in the development of acute lymphoblastic leukemia (ALL) subtypes associated with adverse prognosis. The use of the polymerase chain reaction (PCR) for the detection of these genetic rearrangements may offer advantages over cytogenetic techniques which are often unsatisfactory in patients with ALL and, furthermore, provide a useful tool for monitoring of residual disease. However, it has not yet been evaluated whether the employment of PCR at the time of diagnosis improves the detection rate of these clinically relevant genetic anomalies. We have developed a multiprimer-PCR protocol which facilitates the detection of each of the four chimeric E2A/PBX1 and BCR/ABL mRNAs in a single reaction. This protocol was used for the evaluation of bone-marrow or blood samples from 251 children with ALL in whom cytogenetic analyses had been performed. Of the 251 patients, 221 had a B-cell precursor immunophenotype. In this group, 21 patients (9.5%) carrying the E2A/PBX1 rearrangement and three patients (1.4%) with BCR/ABL transcripts were detected by PCR. Twelve of these cases had escaped the detection by conventional cytogenetic analysis. In two of 12 patients with a typical t(1;19)(q23;p13), no E2A/PBX1 transcripts were identified by PCR, thus suggesting the presence of different molecular rearrangements. Residual leukemic cells were detected by PCR in five of eight patients who were followed during complete clinical remission. The frontline use of PCR has an important impact on the timely diagnosis, therapeutic decisions, and monitoring of high-risk patients with B-cell precursor leukemia who carry the E2A/PBX1 or BCR/ABL fusion genes.

Adolescent↗
PubMed1992

Favorable outcome of B-cell acute lymphoblastic leukemia in childhood: a report of three consecutive studies of the BFM group.

In 1981 the BFM group introduced a new treatment strategy for B-cell acute lymphoblastic leukemia (B-ALL). A cytoreductive prephase (prednisone/cyclophosphamide) was followed by eight 5-day courses of chemotherapy. Fractionated cyclophosphamide, methotrexate (MTX) 0.5 g/m2 (24-hour infusion), and MTX intrathecally were administered at each course and cytosine arabinoside (ARA-C)/teniposide (VM-26) was given alternately with doxorubicin. In study ALL-BFM-83, central nervous system (CNS) chemotherapy was intensified by adding dexamethasone, while MTX/ARA-C was administered intraventricularly. Therapy duration was reduced to six courses. In study ALL-BFM-86, MTX 0.5 g/m2 was replaced by high-dose (HD) MTX, 5 g/m2 (24-hour infusion), and MTX/ARA-C/prednisolone intrathecal therapy was introduced. Doses of ARA-C and VM-26 were increased and fractionated, cyclophosphamide was partially replaced by ifosfamide, and vincristine was added. CNS irradiation was 24 Gy for prevention and 30 Gy for overt disease in studies ALL-BFM-81 and -83, but was omitted in ALL-BFM-86. In all, 87 patients were enrolled, 22 (8 CNS-positive) in study All-BFM-81, 24 (7 CNS-positive) in study ALL-BFM-83, and 41 (0 CNS-positive) in study ALL-BFM-86. The estimated 5-year duration of event-free survival (EFS) was 43% in study ALL-BFM 81, 50% in study ALL-BFM-83, and 78% in study ALL-BFM-86 (minimal follow-up, 25 months). Nineteen of 24 relapses occurred while on therapy or shortly thereafter. In study ALL-BFM 81, the CNS was the most frequent site of failure. In ALL-BFM-83, there were no isolated CNS relapses, but more bone marrow (BM) relapses occurred. In ALL-BFM-86, localized manifestations were the predominant site of failure, no isolated BM relapses occurred, and only one CNS relapse was diagnosed. No single parameter exerted a consistent influence on outcome with one exception. The presence of residual disease after the first two courses was correlated with an increased risk of therapy failure. We conclude that an intensive, short-pulse therapy delivered within a 4-month period is highly effective in the treatment of B-ALL. In addition to fractionated cyclophosphamide/ifosfamide, a 24-hour infusion of HD MTX 5 g/m2 in conjunction with an i.th. therapy is an important component for prevention of both systemic and CNS relapses. CNS irradiation is not needed for CNS-negative patients.

Adolescent↗
PubMed1992

Chemotherapy versus bone marrow transplantation in childhood acute lymphoblastic leukaemia. BFM Study Group.

Twenty-five years ago over 90% of children with acute lymphoblastic leukaemia (ALL) died of this disease. Dramatic improvement has been achieved since then by employing risk-adapted, aggressive polychemotherapy protocols. More than 90% of children with ALL treated according to, for example BFM-protocols, have nowadays cure rates in the range of 70%-80%. However, 10% of patients do not initially respond adequately to standard induction chemotherapy. They are characterized by distinct chromosomal abnormalities such as translocation (9; 22) or combinations of early treatment failure and other risk factors as cytogenetic abnormalities, lineage-specific surface markers or tumour load at diagnosis. In this group of patients in first complete remission and certainly in the vast majority of relapsed patients, allogeneic bone marrow transplantation (BMT) has evolved as an alternative approach allowing further intensification of myeloablation and the introduction of an additional antileukaemic alloreactivity. Nevertheless, the decision for a marrow transplant in children has to be made very carefully because of a significant increase in treatment related mortality and BMT-specific risks like acute and chronic graft-versus-host disease with a critical iatrogenic chronic morbidity. This is even more evident, if mismatched or unrelated transplants are being considered. The indications for one or the other treatment modality according to the current BFM strategy are discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Detection of chimeric BCR-ABL genes in acute lymphoblastic leukaemia by the polymerase chain reaction.

Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL) is most common in adults and is associated with poor prognosis. Since karyotypic identification of the Philadelphia translocation has been hampered by technical difficulties, we used the polymerase chain reaction (PCR) to look for the BCR-ABL rearrangement in stored samples from a selected group of 314 German ALL patients. BCR-ABL transcripts were found in 77 of 179 adults and were restricted to those with B-precursor leukaemias. 55% of adult common ALL patients had BCR-ABL and its presence correlated with poor overall survival and remission duration. Of 135 children with common ALL, 5 (6%) primary cases and 8 (17%) with recurrent neoplasias were PCR-positive. We recommend prospective evaluation of BCR-ABL analysis with PCR in patients with a B-precursor leukaemia.

Adult↗
PubMed1991

Use of polymerase chain reactions to monitor minimal residual disease in acute lymphoblastic leukemia patients.

T-cell receptor (TCR) delta gene rearrangements are observed in more than 80% of acute lymphoblastic leukemia (ALL) patients. Moreover, a preferential usage of specific genetic elements has been shown in different ALL subtypes: V delta 1 DJ delta 1 rearrangements predominate in T-ALL, while most B-precursor ALLs show a recombination of V delta 2 to D delta 3. Recently we have proposed a strategy for the detection of minimal residual disease (MRD) based on the isolation of clonospecific probes following the in vitro amplification of V delta 1 DJ delta 1 junctions by polymerase chain reaction (PCR) and now have adapted this method to the preparation of specific V delta 2 D delta 3 fragments. In the present study, clonospecific probes were generated from 11 T-ALL and 16 cALL patients (21 children, 6 adults). The sensitivity of these 27 probes in detecting residual leukemia cells varied between 10(-4) to 10(-6) as determined by semiquantitative evaluation of dilution experiments. PCR analysis of 55 bone marrow (BM) and peripheral blood (PB) samples obtained from the 27 patients during complete clinical remission showed the following results: (1) Evidence for MRD was obtained in the BM of all patients (eight of eight) investigated 2 to 6 months after remission induction and also in 6 of 11 cases on maintenance therapy 7 to 19 months after diagnosis. (2) In contrast, all patients but one (10 of 11) analyzed 6 to 41 months after the termination of treatment lacked apparent evidence for leukemia DNA; the exception was a girl exhibiting 10(-4) to 10(-5) residual cells in her PB 5.5 years after diagnosis. (3) Longitudinal analysis in nine patients disclosed marked individual differences in the intervals between achievement of clinical remission and complete eradication of the leukemia cell clone. (4) Differences in the duration of MRD were not associated with distinct clinical-hematologic features. (5) Detection of residual disease by PCR proceeded clinical relapse in two cases.

Blotting, Southern↗
PubMed1990

Differential effects of granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor in children with severe congenital neutropenia.

Severe congenital neutropenia (SCN) is a disorder of myelopoiesis characterized by severe neutropenia secondary to a maturational arrest at the level of promyelocytes. We treated five patients with SCN with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for 42 days and subsequently, between 1 and 3 months later, with rhG-CSF for 142 days. The objective was to evaluate the safety and ability of these factors to elicit a neutrophil response. rhGM-CSF was administered at a dose of 3 to 30 micrograms/kg/d (30 to 60 minutes, intravenously). In all patients, a specific, dose-dependent increase in the absolute granulocyte counts was observed. However, in four patients this increase was due to an increase in eosinophils, and in only one patient it was due to an increase in the absolute neutrophil counts (ANC). Subsequently, all patients received rhG-CSF at a dose of 3 to 15 micrograms/kg/d subcutaneously. In contrast to rhGM-CSF treatment, all five patients responded to rhG-CSF during the first 6 weeks of treatment with an increase in the ANC to above 1,000/microL. The level of ANC could be maintained during maintenance treatment. In one patient, the increase in ANC was associated with an improvement of a severe pneumonitis caused by Peptostreptococcus and resistant to antibiotic treatment. No severe bacterial infections occurred in any of the patients during CSF treatment. All patients tolerated rhGM-CSF and rhG-CSF treatment without severe side effects. These results demonstrate the beneficial effect of rhG-CSF in SCN patients.

Agranulocytosis↗
PubMed1990

Central nervous system relapse prevention in 1165 standard-risk children with acute lymphoblastic leukemia in five BFM trials.

In treatment of childhood ALL, prevention of CNS relapse by cranial irradiation is followed by considerable long-term sequelae. In the three ALL-BFM (Berlin-Frankfurt-Münster) trials 70, 76, and 79, employing radiotherapy (8.5 Gy craniospinal, 18 or 24 Gy cranial irradiation) in all arms, the incidence of CNS relapses (isolated and combined) in standard-risk patients (SR, 60% of all children) was consistently less than 6%. A risk factor (RF) calculated from absolute blast number, liver, and spleen size at diagnosis was used to stratify patients in the subsequent trials ALL-BFM 81 and 83. In ALL-BFM 81, SR patients (RF less than 1.2) were randomized to receive 18 Gy cranial irradiation or intermediate-dose i.v. methotrexate (ID-MTX) (4 x 0.5 g/m2). In ALL-BFM 83, the SR group was further subdivided into group SR low (SR-L, RF less than 0.8) and group SR high (SR-H, RF 0.8 - less than 1.2). SR-L patients received no irradiation, and were tested by randomization for the effectiveness of an intensive reinduction regimen (protocol III). SR-H patients were randomized for 12 or 18 Gy. The results were as follows: In patients of both trials with RF less than 0.8, radiotherapy could be replaced by ID-MTX plus protocol III. Without protocol III, relapses increased from 15.7% to 31.7%. Concomitantly, the fraction of relapses with CNS involvement increased from 26.7% to 36.4%. However, SR patients with RF between 0.8 and 1.2 could not be protected by reinduction alone (isolated/overall CNS relapse rate with irradiation, 4%/5%; without irradiation, 11%/22%). Dosages of 12 and 18 Gy were found to be equally protective.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Acute onset deafness in a 4-year-old girl after a single infusion of cis-platinum.

Dose-dependent reduction of auditory function mainly in the high frequency range has been described as a common adverse side effect of cis-platinum. Here we report on a 4-year-old girl with osteosarcoma of the right distal femur who developed acute bilateral deafness 3 days after a single infusion of high-dose cis-platinum (150 mg/m2) during preoperative chemotherapy. Sudden disabling ototoxicity should be considered when administering high-dose cis-platinum to young children.

Acute Disease↗
PubMed1989

Structure of [N,N'-propylenebis(2-pyrrolylmethyleneaminato)]nickel(II).

[Ni(C13H14N4)], Mr = 284.98, monoclinic, P2(1)/c, a = 10.096 (2), b = 9.360 (2), c = 30.565 (4) A, beta = 119.45 (2) degrees, V = 2515.1 (9) A3, Z = 8, Dx = 1.505 g cm-3, Cu K alpha, lambda = 1.5418 A, mu = 20.22 cm-1, F(000) = 1168, T = 298 (2) K, 437 parameters refined, final R = 0.038 for all 2587 reflections. The complex takes a square-planar geometry around the Ni atom. Although the coordination geometries of the two crystallographically independent complexes are quite similar to each other, significant differences in planarity and Ni-N distances are observed.

Crystallization↗
PubMed1989

The dilemma of chromosomal mosaicism in chorionic villus sampling--'direct' versus long-term cultures.

Chromosomal mosaicism is one of several unanswered dilemmas in first-trimester prenatal diagnosis. We report the course of a pregnancy in which a normal karyotype was detected on direct CVS preparation and fetal blood, 100 per cent trisomy 21 in one long-term CVS culture, and low-rate trisomy 21 mosaicism in a second long-term CVS culture and amniocentesis. The phenotypically normal infant had a 6 per cent mosaicism of trisomy 21. It appears that a persistent low-rate mosaicism in different tissues may be indicative of the true status of the fetus.

Adult↗