Online monitoring of cell metabolism for studying pharmacodynamic effects

To characterize modes of action of substances and their cytotoxic effects Bionas GmbH has developed a new screening system to allow the continuous recording of how an active substance can act (Bionas 2500 analyzing system). In the pharmaceutical industry it is important to acquire as much information as possible about the metabolic effects of an active substance. Most classical pre-clinical studies are very expensive and time-consuming. Often they are so-called end-point tests which require many individual tests before approximate statements can be made about how an effect takes its course. With the Bionas 2500 analyzing system metabolically relevant data including oxygen consumption, acidification rate and the adhesion (cell impedance) of cells can be measured in parallel, online and label-free. Using e.g. ion-sensitive field effect-transistors (ISFET) and electrode structures it is possible to observe metabolic parameters non-invasively and continuously over longer periods of time. The system has already been established for several cell models, cell lines as well as primary cells. It also offers the advantage that regenerative effects can be observed during the same test run.     

Clinical course of attention-deficit/hyperactivity disorder from childhood toward early adolescence

OBJECTIVE: To study the course of attention-deficit/hyperactivity disorder (ADHD) in late childhood to adolescence using a multi-informant and multi-assessment procedure. METHOD: Subjects were 35 children with ADHD and 35 matched controls with a mean age of 10 years at first assessment. DSM-III-R-based structured diagnostic interviews and behavioral questionnaires based on parents, teachers, and youth informants were used. Cross-informant behavioral syndromes were obtained by use of the Child Behavior Checklist, the Teacher's Report Form, and the Youth Self-Report. Subjects were reassessed after 1.5 and 2.6 years. RESULTS: Behavioral differences between the two groups were significant for the majority of scales for all three informants at all three times. Diagnostic interviews revealed a persistence rate of 46% over 2.6 years. However, there were only few significant behavioral differences across informants between the nonpersistent and the persistent groups. The fit between interview-derived syndrome scores reflecting subtypes of ADHD and both parents and youth questionnaire data was good, whereas for the teacher ratings it was poor. A high rate of 89% correct classification of the outcome diagnoses was possible based on behavioral data at time 1. CONCLUSIONS: The study of the course of ADHD should be based both on interview and questionnaire data and should include several informants. Operationally defined diagnoses alone may lead to an underestimation of persistent behavioral problems.     

Seroepidemiologische Studie zur Überwachung der Diphtherie-Immunität und Diphtherie-Schutz-impfung im Freistaat Sachsen 1996

Zusammenfassung  1996 wurden zur Beurteilung der Immunit?tslage der s?chsischen Bev?lkerung gegen Diphtherie 1378 Seren von Personen untersichiedlichen Alters im Zellkulturtest nach Miyamura auf neutralisierende Diphtherie-Antitoxingehalte untersucht (immunit?tskataster). An 203 Personen, bei denen eine Indikation zur Wiederimpfung vorlag, wurde die Boosterf?higkeit in Abh?ngigkeit von der dokumentierten Grundimmunisierung, der Anzahl der Widerimpfungen und nach dem Abstand zur letzten Impfung mit der gleichen Methodik beurteilt. Die Erfassung der diesbezüglich notwendigen personenbezogenen Angaben, die Serumgewinnung und Impfdurchführung erfolgte durch die Gesundheits?mter nach einem vorgegebenen Programm. Die Immunit?tslage der Bev?lkerung Sachsens, wohl stellvertretend für alle neuen Bundesl?nder, ist dank der 1961–1990 praktizierten Pflichtimpfung 1996 insgesamt noch mit ausreichend gut zu bewerten: 70% waren sicher, 17,7% relativ und nur 12,3% nicht geschützt. Unbefriedigend ist die Immunit?tslage bei den über, 40j?hrigen. Eine Boosterf?higkeit ist in Abh?ngigkeit von der dokumentierten Grundimmunisierung unterschiedlich zu beurteilen. Auch bei Jahrzehnte zurückliegender vollst?ndiger und dokumentierter Grundimmunisierung reicht eine einmalige Boosterimpfung aus, um einen vollst?ndigen Impfschutz zu induzieren. Nicht so bei unbekannter, aus dem Ged?chtnis benannter, Impfanamnese. Hier ist eine Vervollst?ndigung der Grundimmunisierung zwingend erforderlich. Summary  In 1996, 1378 sera of persons of different age were examined for neutralizing diphtheria antitoxin levels by the cell culture test according to Miyamura to evaluate the diphtheria immunity situation among the population in Saxony (immunity register). In 203 persons in which revaccination was indicated, the booster capacity has been evaluated by the same method based on the documented basic immunization, the number of revaccinations and the time which had passed since the last vaccination. Recording of the respective personal data, serum production and vaccination were performed by the public health departments according to a specific programme. The overallimmunity situation among the population in Saxony which is presumably representative of all new Federal L?nder was rated as still sufficient due to compulsory vaccination that had been performed between 1961 and 1990: 70% showed sufficient, 17.7% a relative and only 12.3% no protection. The immunity situation in persons above 40 years of age was unsatisfactory. Whether there is a booster capacity will depend on the documented basic immunization. A single booster vaccination is sufficient in order to induce complete protection, even if the complete and documented basic immunization took place decades ago. This is not the case when the vaccination history has been recalled by vacciness from their personal memory. In this case, completion of basic immunization is an absolute necessity.      

Molecular definition of chromosome arm 5q deletion end points and detection of hidden aberrations in patients with myelodysplastic syndromes and isolated del(5q) using oligonucleotide array CGH

Isolated deletions of the long arm of chromosome 5, del(5q), are observed in 10% of myelodysplastic syndromes (MDS) and are associated with a more favorable prognosis, although the clinical course varies considerably. If one or more additional chromosomal aberrations are present, this correlates with a significantly shorter overall survival. To assess the frequency of hidden abnormalities in cases with an isolated cytogenetic del(5q), we have performed a genome wide high resolution 44 K 60mer oligonucleotide array comparative genomic hybridization (aCGH) study using DNA from bone marrow cells of 12 MDS and one AML patient. In one case a single additional hidden 5.6 Mb deletion of 13q14 and in another case multiple larger aberrations involving many chromosomes were found. Fluorescence in situ hybridization demonstrated that aberrations present in 35% of the bone marrow cells can be detected by aCGH. Furthermore with oligonucleotide aCGH the deletion end points in 5q were mapped precisely, revealing a cluster of proximal breakpoints in band q14.3 (n = 8) and a distal cluster between bands q33.2 and q34 (n = 11). This study shows the high resolution of oligonucleotide CGH arrays for precisely mapping genomic alterations and for refinement of deletion end points. In addition, the high sensitivity of this method enables the study of whole bone marrow cells from MDS patients, a disease with a low blast count.     

Photoreduction of ferredoxin with various electron donors: Support for the Z scheme of photosynthetic electron transport

The currently accepted scheme for photosynthetic electron flow from water to ferredoxin (and subsequently to NADP), known as the Z scheme, envisions a linear electron flow that requires two photosystems joined by several electron carriers. The observation that the extent of photoreduction of ferredoxin depends on whether electrons are provided by water (a donor to photosystem II) or by artificial electron donors to photosystem I led Arnon et al. [Arnon, D. I., Tsujimoto, H. Y. & Tang, G. M.-S. (1980) Proc. Natl. Acad. Sei. USA 77, 2676-2680] to question the validity of the Z scheme for photosynthetic electron transport. Our results show that this difference is not due to any inherent difference in electron transport but to the fact that when electron donors are added to chloroplasts they oxidize (in their oxidized state) reduced ferredoxin. Different electron donors oxidize reduced ferredoxin to a different extent; dehydroascorbate is a more potent oxidant than dithiothreitol. Dichlorophenol-indophenol is also a potent oxidant of reduced ferredoxin. The rate of NADP reduction and the K_m for NADP with various electron donors reflect the oxidative capacities of the electron donors and mediators. These results also explain the fact that NADP reduction with electron donors to photosystem I is less than that with water, despite the fact that electron flow from donor to artificial dyes can proceed at high rates.     

Marrow transplantation for chronic myeloid leukemia: a randomized study comparing cyclophosphamide and total body irradiation with busulfan and cyclophosphamide

A prospective randomized study was conducted comparing two conditioning regimens for the treatment of patients with chronic myeloid leukemia in chronic phase by marrow transplantation from HLA identical siblings. Sixty-nine patients received 60 mg/kg of cyclophosphamide on each of 2 successive days followed by 6 fractions of total body irradiation each of 2.0 Gy (CY-TBI), and 73 patients received 16 mg/kg of busulfan delivered over 4 days followed by 60 mg/kg CY on each of 2 successive days (BU-CY). There was no significant difference between the CY-TBI and the BU-CY groups in the 3-year probabilities of survival (0.80 for both), relapse (0.13 for both), or event-free survival (CY-TBI, 0.68; BU-CY, 0.71) or in speed of engraftment or incidence of venocclusive disease of the liver. The 4-year probabilities of survival and event- free survival for patients transplanted within 1 year of diagnosis were 0.86 and 0.72, respectively, for each group. Significantly more patients in the CY-TBI group experienced major creatinine elevations. There was significantly more acute graft-versus-host disease in the CY- TBI group. Fever days, positive blood cultures, hospitalizations, and inpatient hospital days were significantly more common in the CY-TBI group than in the BU-CY group. In conclusion, the BU-CY regimen was better tolerated than, and associated with survival and relapse probabilities that compare favorably with, the CY-TBI regimen.     

Marrow harvesting from normal donors

The experience at a single institution in harvesting marrow for allogeneic transplantation on 1,270 occasions from 1,160 normal donors is presented in detail, together with an analysis of all the donor complications. Four donors were less than 2 years old, and the youngest was 6 1/2 months. No special difficulties were encountered with these young donors. Hospitalization time was three days or less for 99% of the procedures. Six donors had life-threatening complications; three of a cardiopulmonary and two of an infectious nature, and one cerebrovascular embolic episode. Significant operative site morbidity, usually transient neuropathies, occurred in ten procedures. Ten percent of the donations were associated with transient postoperative fever of unknown origin. Increasing donor age was associated with a reduction of the cellularity of the marrow harvest. The use of stored autologous blood permitted the avoidance of blood bank transfusion in 81% of males, 69% of females, and 50% of children. It was concluded that the procedure was associated with a very low risk of complication, but that the involvement of normal donors in such an operation justifies stringent monitoring.     

Allogeneic marrow transplantation for refractory anemia: a comparison of two preparative regimens and analysis of prognostic factors

From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3- year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data.