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1.
J Laryngol Otol ; 137(1): 61-67, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35611593

ABSTRACT

OBJECTIVE: This study investigated mobile health enabled surveillance in ototoxicity. METHOD: This was a longitudinal study of 32 participants receiving chemotherapy. Baseline and exit audiograms that included conventional and extended high frequency audiometry were recorded within the patient's treatment venue using a validated mobile health audiometer. RESULTS: Average hearing thresholds at baseline were within the normal range (81.2 per cent left; 93.8 per cent right), reducing at exit testing (71.9 per cent left; 78.1 per cent right). Half of participants presented with a threshold shift according to ototoxicity monitoring criteria. The frequencies affected the most were between 4000 and 16 000 Hz, with left ears significantly more affected than right ears. Noise levels exceeded the maximum permissible ambient noise levels in up to 43.8 per cent of low frequencies (250-1000 Hz). CONCLUSION: Mobile health supported audiometry proved to be an efficacious tool for ototoxicity monitoring at the treatment venue. Changes in hearing ability over time could be tracked, improving surveillance in patients with full treatment schedules.


Subject(s)
Antineoplastic Agents , Ototoxicity , Humans , Cisplatin/adverse effects , Antineoplastic Agents/adverse effects , Platinum/adverse effects , Longitudinal Studies , Ototoxicity/etiology , Audiometry , Audiometry, Pure-Tone , Auditory Threshold
2.
J Clin Endocrinol Metab ; 101(4): 1656-63, 2016 04.
Article in English | MEDLINE | ID: mdl-26844843

ABSTRACT

CONTEXT: Primary aldosteronism (PA) is the most common cause of secondary hypertension. Aldosterone excess can cause DNA damage in vitro and in vivo. Single case reports have indicated a coincidence of PA with renal cell carcinoma and other tumors. However, the prevalence of benign and malignant neoplasms in patients with PA has not yet been studied. PATIENTS AND DESIGN: In the multicenter MEPHISTO study, the prevalence of benign and malignant tumors was investigated in 335 patients with confirmed PA. Matched hypertensive subjects from the population-based Study of Health in Pomerania cohort served as controls. RESULTS: Of the 335 PA patients, 119 (35.5%) had been diagnosed with a tumor at any time, and 30 had two or more neoplasms. Lifetime malignancy occurrence was reported in 9.6% of PA patients compared to 6.0% of hypertensive controls (P = .08). PA patients with a history of malignancy had higher baseline aldosterone levels at diagnosis of PA (P = .009), and a strong association between aldosterone levels and the prevalence of malignancies was observed (P = .03). In total, 157 neoplasms were identified in the PA patients; they were benign in 61% and malignant in 25% of the cases (14% of unknown dignity). Renal cell carcinoma was diagnosed in five patients (13% of all malignancies) and was not reported in controls CONCLUSION: Compared to hypertensive controls, the prevalence of malignancies was positively correlated with aldosterone levels, tended to be higher in PA patients, but did not differ significantly.


Subject(s)
Aldosterone/blood , Biomarkers, Tumor/blood , Hyperaldosteronism/physiopathology , Hypertension/physiopathology , Neoplasms/epidemiology , Adult , Aged , Blood Pressure , Case-Control Studies , Female , Germany/epidemiology , Humans , Male , Middle Aged , Neoplasms/blood , Neoplasms/diagnosis , Prevalence , Prospective Studies , Retrospective Studies
3.
J Laryngol Otol ; 128(9): 772-9, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25166876

ABSTRACT

BACKGROUND: This study compared vestibulocollic reflex and vestibulo-ocular reflex functioning in subjects with and without human immunodeficiency virus. It also described test results throughout progression of the disease and compared the results of human immunodeficiency virus positive subjects who were receiving antiretroviral therapies with those not receiving this treatment. METHODS: Subjects comprised 53 adults with human immunodeficiency virus (mean age 38.5 ± 4.4 years) and 38 without human immunodeficiency virus (mean age 36.9 ± 8.2 years). Clinical examinations included cervical vestibular-evoked myogenic potential and bithermal caloric testing. RESULTS: Abnormal cervical vestibular-evoked myogenic potential and caloric results were significantly higher in the human immunodeficiency virus positive group (p = 0.001), with an odds ratio of 10.2. Vestibulocollic reflex and vestibulo-ocular reflex involvement increased with progression of the disease. There were more abnormal test results in subjects receiving antiretroviral therapies (66.7 per cent) than in those not receiving antiretroviral therapies (63.6 per cent), but this difference was insignificant. CONCLUSION: Human immunodeficiency virus seems to influence vestibulocollic reflex pathways. Combining cervical vestibular-evoked myogenic potential and caloric testing may be useful to detect early neurological involvement in human immunodeficiency virus positive subjects.


Subject(s)
HIV Seropositivity/complications , Reflex, Vestibulo-Ocular/physiology , Vestibular Diseases/physiopathology , Adult , Anti-HIV Agents/therapeutic use , Case-Control Studies , Disease Progression , Eye Movement Measurements , Female , Humans , Male , Middle Aged , Vestibular Evoked Myogenic Potentials , Young Adult
4.
J Laryngol Otol ; : 1-9, 2014 Mar 19.
Article in English | MEDLINE | ID: mdl-24642276

ABSTRACT

Objective: To characterise auditory involvement secondary to excessive craniotubular bone growth in individuals with sclerosteosis in South Africa. Methods: This cross-sectional study assessed the auditory profile of 10 participants with sclerosteosis. An auditory test battery was used and results for each ear were recorded using descriptive and comparative analyses. Results: All participants presented with bilateral, mixed hearing losses. Of the 20 ears, hearing loss was moderate in 5 per cent (n = 1), severe in 55 per cent (n = 11) and profound in 40 per cent (n = 8). Air-bone gaps were smaller in older participants, although the difference was not statistically significant (p > 0.05). Computed tomography scans indicated pervasive abnormalities of the external auditory canal, tympanic membrane, middle-ear space, ossicles, oval window, round window and internal auditory canal. Narrowed internal auditory canals corresponded to poor speech discrimination, indicative of retrocochlear pathology and absent auditory brainstem response waves. Conclusion: Progressive abnormal bone formation in sclerosteosis involves the middle ear, the round and oval windows of the cochlea, and the internal auditory canal. The condition compromises conductive, sensory and neural auditory pathways, which results in moderate to profound, mixed hearing loss.

5.
J Laryngol Otol ; 125(9): 881-90, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21729430

ABSTRACT

INTRODUCTION: Disorders of the auditory and vestibular system are often associated with human immunodeficiency virus infection and acquired immunodeficiency syndrome. However, the extent and nature of these vestibular manifestations are unclear. OBJECTIVE: To systematically review the current peer-reviewed literature on vestibular manifestations and pathology related to human immunodeficiency virus and acquired immunodeficiency syndrome. METHOD: Systematic review of peer-reviewed articles related to vestibular findings in individuals with human immunodeficiency virus infection and acquired immunodeficiency syndrome. Several electronic databases were searched. RESULTS: We identified 442 records, reduced to 210 after excluding duplicates and reviews. These were reviewed for relevance to the scope of the study. DISCUSSION: We identified only 13 reports investigating vestibular functioning and pathology in individuals affected by human immunodeficiency virus and acquired immunodeficiency syndrome. This condition can affect both the peripheral and central vestibular system, irrespective of age and viral disease stage. Peripheral vestibular involvement may affect up to 50 per cent of patients, and central vestibular involvement may be even more prevalent. Post-mortem studies suggest direct involvement of the entire vestibular system, while opportunistic infections such as oto- and neurosyphilis and encephalitis cause secondary vestibular dysfunction resulting in vertigo, dizziness and imbalance. CONCLUSION: Patients with human immunodeficiency virus and acquired immunodeficiency syndrome should routinely be monitored for vestibular involvement, to minimise functional limitations of quality of life.


Subject(s)
Acquired Immunodeficiency Syndrome/complications , HIV Infections/complications , Hearing Disorders/virology , Vestibular Diseases/virology , AIDS-Related Opportunistic Infections/complications , AIDS-Related Opportunistic Infections/epidemiology , Acquired Immunodeficiency Syndrome/epidemiology , Antiretroviral Therapy, Highly Active/adverse effects , Autopsy , Databases, Bibliographic , Dizziness/epidemiology , Dizziness/physiopathology , Dizziness/virology , Ear, Inner/pathology , Ear, Inner/physiopathology , Ear, Inner/virology , HIV Infections/epidemiology , Hearing Disorders/complications , Hearing Disorders/epidemiology , Humans , Prevalence , Quality of Life , Vestibular Diseases/complications , Vestibular Diseases/epidemiology , Vestibular Function Tests/methods
7.
Heredity (Edinb) ; 98(2): 74-84, 2007 Feb.
Article in English | MEDLINE | ID: mdl-16985509

ABSTRACT

The use of admixed human populations to scan the genome for chromosomal segments affecting complex phenotypic traits has proved a powerful analytical tool. However, its potential in other organisms has not yet been evaluated. Here, we use DNA microsatellites to assess the feasibility of this approach in hybrid zones between two members of the 'model tree' genus Populus: Populus alba (white poplar) and Populus tremula (European aspen). We analyzed samples of both species and a Central European hybrid zone (N=544 chromosomes) for a genome-wide set of 19 polymorphic DNA microsatellites. Our results indicate that allele frequency differentials between the two species are substantial (mean delta=0.619+/-0.067). Background linkage disequilibrium (LD) in samples of the parental gene pools is moderate and should respond to sampling schemes that minimize drift and account for rare alleles. LD in hybrids decays with increasing number of backcross generations as expected from theory and approaches background levels of the parental gene pools in advanced generation backcrosses. Introgression from P. tremula into P. alba varies strongly across marker loci. For several markers, alleles from P. tremula are slightly over-represented relative to neutral expectations, whereas a single locus exhibits evidence of selection against P. tremula genotypes. We interpret our results in terms of the potential for admixture mapping in these two ecologically divergent Populus species, and we validate a modified approach of studying genotypic clines in 'mosaic' hybrid zones.


Subject(s)
Hybridization, Genetic , Linkage Disequilibrium , Populus/genetics , Alleles , Europe , Gene Frequency , Genetic Linkage , Genetic Markers , Genetic Variation , Genotype , Microsatellite Repeats , Regression Analysis
8.
Science ; 313(5793): 1596-604, 2006 Sep 15.
Article in English | MEDLINE | ID: mdl-16973872

ABSTRACT

We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.


Subject(s)
Gene Duplication , Genome, Plant , Populus/genetics , Sequence Analysis, DNA , Arabidopsis/genetics , Chromosome Mapping , Computational Biology , Evolution, Molecular , Expressed Sequence Tags , Gene Expression , Genes, Plant , Oligonucleotide Array Sequence Analysis , Phylogeny , Plant Proteins/chemistry , Plant Proteins/genetics , Polymorphism, Single Nucleotide , Populus/growth & development , Populus/metabolism , Protein Structure, Tertiary , RNA, Plant/analysis , RNA, Untranslated/analysis
9.
Mol Ecol ; 14(4): 1045-57, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15773935

ABSTRACT

The renewed interest in the use of hybrid zones for studying speciation calls for the identification and study of hybrid zones across a wide range of organisms, especially in long-lived taxa for which it is often difficult to generate interpopulation variation through controlled crosses. Here, we report on the extent and direction of introgression between two members of the "model tree" genus Populus: Populus alba (white poplar) and Populus tremula (European aspen), across a large zone of sympatry located in the Danube valley. We genotyped 93 hybrid morphotypes and samples from four parental reference populations from within and outside the zone of sympatry for a genome-wide set of 20 nuclear microsatellites and eight plastid DNA restriction site polymorphisms. Our results indicate that introgression occurs preferentially from P. tremula to P. alba via P. tremula pollen. This unidirectional pattern is facilitated by high levels of pollen vs. seed dispersal in P. tremula (pollen/seed flow = 23.9) and by great ecological opportunity in the lowland floodplain forest in proximity to P. alba seed parents, which maintains gene flow in the direction of P. alba despite smaller effective population sizes (N(e)) in this species (P. alba N(e)c. 500-550; P. tremula N(e)c. 550-700). Our results indicate that hybrid zones will be valuable tools for studying the genetic architecture of the barrier to gene flow between these two ecologically divergent Populus species.


Subject(s)
DNA, Plant/genetics , Genetics, Population , Hybridization, Genetic , Populus/genetics , Austria , Ecology , Genetic Variation , Geography , Haplotypes , Microsatellite Repeats/genetics , Plastids/genetics , Polymorphism, Restriction Fragment Length , Population Density
10.
Leukemia ; 18(9): 1460-7, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15284854

ABSTRACT

Bone marrow fibrosis (MF) has been shown to indicate therapy failure in Ph(+) chronic myeloid leukemia (CML). However, the results on the development of MF during interferon-alpha therapy of CML are controversial. The significance of the interferon dose has not been considered as yet. In total, 627 bone marrow biopsies taken prospectively from 200 patients with CML recruited in two studies using different doses of interferon-alpha +/- low-dose cytosine arabinoside were examined for MF before and during therapy. The results showed that the risk of MF depended significantly on the interferon-alpha dose applied (P<0.000005). MF progressed during low-dose therapy (3 x 5 x 10(6) IU/week), but was prevented from progression when applying high dose (5 x 10(6) IU/m(2)/per day). MF disappeared when high-dose interferon-alpha was combined with low-dose cytosine arabinoside (P<0.000005). The risk of death markedly increased when MF occurred or progressed (P<0.0009), independent of all other prognostic factors evaluated including the cytogenetic response. In conclusion, the effectiveness of interferon-alpha on MF depends on the treatment intensity. MF reverses when combining high-dose interferon-alpha with low-dose cytosine arabinoside, but progresses when applying low-dose interferon-alpha. MF appears to be a significant early indicator of ineffective therapy in CML.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Marrow/pathology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Primary Myelofibrosis/etiology , Adult , Biopsy , Chromosome Aberrations , Controlled Clinical Trials as Topic , Cytarabine/administration & dosage , Cytogenetic Analysis , Disease Progression , Drug Resistance, Neoplasm , Female , Humans , Interferon-alpha/administration & dosage , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality , Male , Middle Aged , Prospective Studies , Risk Factors , Survival Rate
11.
Leukemia ; 17(12): 2444-53, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14562117

ABSTRACT

Marrow fibrosis (MF) has rarely been considered in therapy studies on chronic myeloid leukemia (CML), and there is a lack of long-term observations on the basis of sequential bone marrow biopsies (BMBs) taken prospectively during the course of disease. A total of 848 BMBs from 400 patients with Ph(+) CML recruited in the German randomized CML study I were examined for MF before and during therapy. In total, 110 patients had been randomized to receive interferon (IFN)-alpha, and 290 to receive chemotherapy (hydroxyurea (HU): 154, busulfan: 136). During IFN-alpha and HU medication, MF was reduced or did not increase for about 2 years. Evolving or progressive MF was an independent and early predictor of therapy failure about 2 years earlier than indicated by changes in the peripheral blood, spleen size, marrow blast count and cytogenetics (P<0.00005), resulting in a significant shortening of the survival times of patients independent of the type of therapy applied including allografting (multivariate analyses; P<0.00005). The analyzed long-term observations strongly indicate that MF is an independent poor prognostic complication of CML, allowing an early prediction of therapy failure. Consideration of the fiber content in marrow may therefore significantly improve the prediction of therapy efficacy and outcome of disease.


Subject(s)
Antineoplastic Agents/administration & dosage , Bone Marrow/pathology , Interferon-alpha/administration & dosage , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Adult , Aged , Antineoplastic Agents, Alkylating/administration & dosage , Biopsy , Bone Marrow Transplantation , Busulfan/administration & dosage , Chromosome Aberrations , Drug Resistance, Neoplasm , Female , Fibrosis , Follow-Up Studies , Humans , Hydroxyurea/administration & dosage , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality , Male , Middle Aged , Prospective Studies , Risk Factors , Survival Analysis , Treatment Failure
12.
Leukemia ; 17(9): 1820-6, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12970782

ABSTRACT

Chronic myeloid leukemia (CML) in older patients has not been studied well. To assess the long-term outcome of older patients with Philadelphia- and/or BCR-ABL-positive CML, 199 patients aged >/=60 years representing 23% of 856 patients enrolled in the German randomized CML-studies I (interferon alpha (IFN) vs hydroxyurea (HU) vs busulfan (BU) and II (IFN+HU vs HU alone) were analyzed after a median observation time of 7 years. In all, 45 patients were treated with Bu, 63 with HU, and 91 with IFN. The 5-year survival was 38% in patients >/=60 years and 47% in patients <60 years (P<0.001). Whereas 5-year survival in chemotherapy-treated older patients was inferior to that in younger patients (33 vs 46%, P=0.006 for HU and 29 vs 38%, P=0.042 for Bu), no significant survival difference could be verified in IFN-treated patients (46 vs 53%, P=0.077). Calculation of age-adjusted, relative survival confirmed these results. Adverse effects of IFN were similar in both age groups, but IFN dosage to achieve treatment goals was lower in older patients. We conclude that the course of CML is not different in the elderly. They require lower IFN doses, achieve the same hematologic and cytogenetic response rates and the same survival advantage at comparable toxicity.


Subject(s)
Antineoplastic Agents/therapeutic use , Interferon-alpha/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Protein-Tyrosine Kinases/metabolism , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Busulfan/therapeutic use , Child , Female , Follow-Up Studies , Fusion Proteins, bcr-abl , Humans , Hydroxyurea/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Leukocyte Count , Male , Middle Aged , Prognosis , Randomized Controlled Trials as Topic , Risk , Survival Rate , Treatment Outcome
13.
Ann Hematol ; 82(2): 83-7, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12601485

ABSTRACT

Due to eligibility criteria not all patients with the disease under investigation can be recruited for therapeutic studies. Thus, the external validity of study results cannot per se be taken for granted. The representativity of the admitted patients is the most relevant determinant for external validity and has to be assessed. As an example we examined the representativity of the patients recruited for the German multicenter study group for adult acute lymphoblastic leukemia (ALL) (GMALL). Lacking nationwide ALL incidence figures available in Germany, a methodology was developed to estimate incidence figures, too. All relevant study groups, hospitals, and diagnostic labs were asked to provide data about patients with ALL newly diagnosed between 1997 and 1998. A matching procedure was developed, as heterogeneous databases had to be pooled and checked for duplicates. Age- and sex-specific incidences of ALL were estimated and compared with the number of patients recruited for the GMALL in the same time period. The purpose was to develop a methodology for estimating incidence figures and evaluating the representativity of patients of the GMALL. The combination of various data sources allowed estimation of reliable incidence data for ALL in Germany. Comparisons with the incidence figures for ALL in other countries and crosschecks within Germany confirm our results. Sixty-two percent of all ALL patients in Germany were admitted to the GMALL study. The recruitment rate of more than 60% of the annual incidence of ALL to the GMALL suggests a high external validity as well as an impact of the study on the patterns of treatment and referral of ALL in adults in Germany. There is no selection bias of patients admitted to the GMALL compared to those patients not included in the study.


Subject(s)
Data Collection/methods , Patient Selection , Precursor Cell Lymphoblastic Leukemia-Lymphoma/epidemiology , Adolescent , Adult , Aged , Bias , Clinical Trials as Topic/standards , Data Collection/standards , Epidemiologic Research Design , Female , Germany , Humans , Incidence , Male , Middle Aged , Registries
14.
Leukemia ; 15(12): 1834-40, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11753602

ABSTRACT

The reliability of routine BCR-ABL RT-nested-PCR was evaluated in 1453 B-lineage ALL or hybrid leukemia at initial diagnosis by RT-nested-PCR. All BCR-ABL-positive (n = 642) and 176 BCR-ABL-negative samples underwent a second RT-PCR. In 518 patients, karyotyping and/or FISH was compared to the BCR-ABL status. The second RT-PCR revealed in 155/642 initially positive samples a divergent result (153 BCR-ABL-negative, two other transcripts) that in most cases turned out to be caused by contaminations in the first RT-nested-PCR. Confirmatory RT-PCR detected 2/176 false negative first RT-nested-PCR results. Thirty-nine specimens remained ambiguous despite different RT-PCR approaches. As far as cytogenetic evaluation and FISH is available (n = 23), the majority but not all patients with an ambiguous RT-PCR result were Ph-negative (n = 18). RT-nested-PCR and cytogenetics yielded in 346 of 383 evaluable samples a concordant result. Differing results are given and account in part to the lower sensitivity of karyotyping. Taken together, confirmed RT-PCR detected BCR-ABL fusion transcripts consistently in 487 out of 1453 ALL samples (c-ALL: 43%, pre-B ALL: 34%, pro-B ALL: 5%, B-ALL: 0%, hybrid leukemia: 5/11). Since false positive initial RT-nested-PCR data were frequent, either confirmatory second RT-PCR or FISH analysis is warranted to guarantee sensitive and reliable results of utmost clinical relevance.


Subject(s)
Burkitt Lymphoma/diagnosis , Fusion Proteins, bcr-abl/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Reverse Transcriptase Polymerase Chain Reaction/standards , Adult , Burkitt Lymphoma/genetics , Cytogenetic Analysis/standards , Diagnostic Errors , Fusion Proteins, bcr-abl/analysis , Humans , Philadelphia Chromosome , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity
15.
Mutat Res ; 452(1): 73-81, 2000 Jul 20.
Article in English | MEDLINE | ID: mdl-10894893

ABSTRACT

Structural chromosome aberrations (SCAs) are sensitive indicators of a preceding exposure of the hematopoietic system to ionizing radiation. Cytogenetic investigations have therefore become routine tools for an assessment of absorbed radiation doses and their biological effects after occupational exposure or radiation accidents. Due to its speed and ease of use, fluorescence in situ hybridization (FISH) with whole chromosome painting (WCP) probes has become a method of choice to visualize SCAs. Until recently, this technique was limited to a rather small number of chromosomes, which could be tested simultaneously. As a result, only a fraction of the structural aberrations present in a sample could be detected and the overall dose effect had to be calculated by extrapolation. The recent introduction of two genome-wide screening techniques in tumor research, i.e., Spectral Karyotyping (SKY) and multicolor FISH (mFISH) now allows the detection of translocations involving any two non-homologous chromosomes. The present study was prompted by our desire to bring the power of mFISH to bear for the rapid identification of radiation-induced SCAs. We chose two model systems to investigate the utility of mFISH: lymphocytes that were exposed in vitro to 3 Gy photons and single hematopoietic progenitor cell colonies isolated from a Chernobyl victim 9 years after in vivo exposure to 5.4 Sv.In lymphocytes, we found up to 15 different chromosomes involved in rearrangements indicating complex radiation effects. Stable aberrations detected in hematopoietic cell colonies, on the other hand, showed involvement of up to three different chromosomes. These results demonstrated that mFISH is a rapid and powerful approach to detect and characterize radiation-induced SCAs in the hemopoietic system. The application of mFISH is expected to result in a more detailed and, thus, more informative picture of radiation effects. Eventually, this technique will allow researchers to rapidly delineate chromosomal breakpoints and facilitate the identification of the genes involved in radiation tumorigenesis.


Subject(s)
Chromosome Aberrations , Hematopoietic Stem Cells/radiation effects , Lymphocytes/radiation effects , Adult , Chromosome Banding , Chromosome Painting , Female , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Humans , Karyotyping , Lymphocytes/cytology , Lymphocytes/metabolism , Male
16.
Int J Radiat Biol ; 75(10): 1241-50, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10549600

ABSTRACT

PURPOSE: The detection of long-term persistent chromosome aberrations in circulating haemopoietic stem cells after accidental radiation exposure. MATERIAL AND METHODS: Peripheral blood samples from highly exposed persons were collected 7-25 years after the radiation accidents in Moscow (1971), Kazan (1975) and Chernobyl (1996). Haemopoietic blood stem cells were analysed when investigating individual colonies derived from haemopoietic progenitor cells: burst-forming units-erythroid (BFU-E), granulocyte-macrophage-colony-forming cells (GM-CFC) and multipotent granulocyte-erythrocyte-macrophage- megakaryocyte-colony-forming cells (GEMM-CFC). Colony formation was obtained in methylcellulose cultures. Chromosome preparations in single colonies were performed using a microtechnique. RESULTS: Nine patients were investigated at 1 to 4 follow-up time points after radiation exposure. Three hundred and thirty-four single colonies were analyzed resulting in 1375 mitoses. It was found that colonies showed chromosome aberrations (ChA) up to 25 years after radiation exposure by classical cytogenetics and by fluorescence in situ hybridization (FISH). Stable aberrations were detected in 21% of colonies. They were clonal in 19% of colonies, i.e. the same abnormality was found in all cells derived from a single colony. In 2% of colonies ChA were stable but non-clonal; unstable ChA were not observed. CONCLUSIONS: The results indicate that blood-derived haemopoietic stem cells may serve as a biological indicator to detect radiation-induced ChA. Since they are considered to be in dynamic and functional exchange with stem cells in the medullary sites of blood cell formation such as bone marrow, the use of blood stem cells as a marker of radiation effects should be explored to assess the repair status of the stem cell pool as such.


Subject(s)
Chromosome Aberrations , Hematopoietic Stem Cells/radiation effects , Radioactive Hazard Release , Adult , Case-Control Studies , Chromosome Banding , Colony-Forming Units Assay , Cytogenetics , Female , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Male , Middle Aged , Moscow , Occupational Exposure , Russia , Time Factors , Ukraine
17.
Stem Cells ; 17(1): 9-17, 1999.
Article in English | MEDLINE | ID: mdl-10215403

ABSTRACT

A biomathematical model was developed to simulate relapse development in patients with chronic myeloid leukemia (CML) following bone marrow transplantation (BMT). The purpose of this study was to better understand the pathophysiology of the time evolution of CML relapse and to provide means whereby the outcomes of patients with CML relapse can be projected and treatment modified accordingly. The model consists of three parallel series of catenated compartments representing granulopoiesis in normal (donor) cells from the marrow, in CML cells from the marrow, and in CML cells from extramedullary sites. It was assumed that CML stem cells were resistant to feedback control and that CML-derived neutrophils, as well as normal neutrophils, exercised feedback regulation of normal stem cells. The known longer generation times for CML neutrophil precursors compared with normal neutrophil precursors were used, and it was assumed that 10(7) pluripotential stem cells were infused with BMT. The model was evaluated for its ability to simulate the reappearance of CML (Philadelphia chromosome positive) metaphases in the marrow and the recovery pattern in the blood neutrophil count in six patients who had relapsed following BMT (allogeneic in three patients, allogeneic with T-cell depletion in two patients, and syngeneic in one patient). The variables tested included the site of origin of the CML stem cells responsible for relapse (marrow alone versus marrow and extramedullary sites), the minimum number of CML stem cells responsible for relapse, and the time delay between BMT and the onset of relapse. Model profiles based on the observed values were obtained in each case. The simulations pointed to the fact that relapse began from a small number of CML cells in medullary and extramedullary sites. The time delay between BMT and the onset of relapse varied from 15 to 240 days. We suggest that this biomathematical model should be further investigated as a possible means of predicting outcome and guiding the treatment for patients with CML relapsing after BMT.


Subject(s)
Bone Marrow Transplantation , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy , Models, Statistical , Adult , Antineoplastic Agents/therapeutic use , Bone Marrow Cells/pathology , Female , Hematopoiesis , Hematopoiesis, Extramedullary , Hematopoietic Stem Cells , Humans , Leukocyte Count , Male , Middle Aged , Models, Biological , Neutrophils/pathology , Philadelphia Chromosome , Recurrence , Time Factors
18.
Br J Haematol ; 103(1): 72-8, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9792292

ABSTRACT

In 140 patients with de novo acute myeloid leukaemia (AML) standard cytogenetics were compared with RT-PCR for the detection of t(8;21), t(15;17) and inv(16) and fluorescence in situ hybridization (FISH) for numerical aberrations of chromosomes 7, 8, X and Y. RT-PCR detected 18 cases with t(8;21), 12 with t(15;17) and seven with inv(16). In two cases with t(8;21), two with t(15;17) and four with inv(16) these aberrations had not been detected by standard cytogenetics. There were no false negative PCR results. In 12 patients with these chromosomal changes, standard cytogenetics revealed additional chromosomal aberrations. In 16 patients sole numerical aberrations of the chromosomes 7, 8, X or Y were found by FISH. In these patients the sensitivity of FISH and standard cytogenetics was comparable. In 87 patients no aberrations could be found by PCR and FISH whereas in 24 of these patients standard cytogenetics revealed an abnormal karyotype. These data recommend the combination of standard cytogenetics and molecular techniques to improve the sensitivity for the detection of genetic lesions in AML. Once chromosomal markers have been identified by combined analysis these markers could be used to monitor residual disease during/after chemotherapy, by RT-PCR and/or FISH.


Subject(s)
Chromosome Aberrations , In Situ Hybridization, Fluorescence/methods , Leukemia, Myeloid, Acute/genetics , Reverse Transcriptase Polymerase Chain Reaction/methods , Adult , Aged , Cytogenetics , Female , Humans , Male , Middle Aged , Prospective Studies
19.
Blood ; 92(6): 1898-909, 1998 Sep 15.
Article in English | MEDLINE | ID: mdl-9731046

ABSTRACT

In contrast to childhood acute lymphoblastic leukemia (ALL), the cell-biological features, clinical characteristics, and treatment outcome of CD10(-) pro-B ALL have not yet been determined in larger series of adult patients. Therefore, we studied 57 adult patients with newly diagnosed pro-B ALL (median age, 30 years) enrolled in two consecutive German multicenter ALL studies (03/87 and 04/89). Extensive immunophenotypic characterization of leukemic blasts could be performed on all patients, whereas adequate cytogenetic data were available in 33 cases and molecular studies in 18 cases, using reverse transcription-polymerase chain reaction to detect MLL-AF-4 transcripts. Twenty-two patients demonstrated a t(4;11)(q21;q23) and/or MLL-AF-4 rearrangements, and 6 patients had other structural abnormalities, including a t(9;22)(q34;q11) (N = 2). Nine patients had a normal karyotype. Patients with 11q23 abnormalities tended to be younger (median age, 29 years) and were characterized by male predominance (64%), hyperleukocytosis (median leukocyte count, 168 x 10(9)/L), and a frequent coexpression of CD65s (64%) as compared with patients with other cytogenetic abnormalities or a normal karyotype. Twelve of 16 (75%) pro-B ALL patients in study 03/87 and 30 of 41 (73%) in study 04/89 achieved a complete remission (CR). Sixteen of 30 patients in study 04/89 remain in continuous CR (CCR) in contrast to only 2 of 12 patients in study 03/87. Interestingly, all 7 patients treated with high-dose cytarabine and mitoxantrone as consolidation in study 04/89 remain alive and leukemia-free. One patient in study 03/87 and 8 in study 04/89 underwent autologous (N = 2) or allogeneic (N = 7) bone marrow transplantation (BMT). The median remission duration was 420 days for patients in study 03/87 and has not yet been reached in study 04/89. The median survival time of all pro-B ALL patients was 571 days in study 03/87 and 747 days in study 04/89. Among the 22 patients with a t(4;11) and/or MLL-AF-4 rearrangements, 17 achieved a CR and 8 are still in CCR, of whom 4 underwent an allogeneic BMT. Remission duration and overall survival did not differ significantly between pro-B ALL patients with 11q23 abnormalities and those with a normal karyotype or other structural abnormalities. These data indicate that intensification of postremission treatment may improve the prognosis of adult pro-B ALL, including patients with a t(4;11).


Subject(s)
Immunophenotyping , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Adolescent , Adult , Aged , Chromosome Aberrations/genetics , Chromosome Aberrations/pathology , Chromosome Disorders , Female , Humans , Karyotyping , Male , Middle Aged , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Remission Induction , Treatment Outcome
20.
Eur J Haematol ; 61(1): 7-13, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9688286

ABSTRACT

The treatment results of 96 patients with Philadelphia-positive chronic myeloid leukemia (CML) in accelerated phase (AP) were reviewed retrospectively. Treatment of AP consisted of allogeneic bone marrow transplantation in 20 (14 related and 6 unrelated donors) or conventional chemotherapy (CC) in 76 patients. Three main treatment strategies were followed in the CC group: continuation (group A) or dose escalation (group B) of chronic phase therapy or change of chronic phase therapy to hydroxyurea (group C). Median survival was 7.0 months in group A (range 1.8-110), in group B 8.3 months (range 0.9-40) and in group C 9.6 months (range 1.5-47.6), p=0.89. Survival in CC was dependent on response to therapy as the achievement of a second chronic phase was significantly associated (p<0.001) with a longer median survival (21 months) compared with stable accelerated phase disease (11 months) or treatment failure (5 months). Median survival in the BMT group was 16.7 months (range 5-77), the 5-yr probability of relapse was 25% and the 5-yr disease-free survival was 36%. For patients <55 yr median survival after BMT was significantly prolonged compared with median survival after CC (n=45, 8.3 months, p=0.008). After developing criteria of AP, median survival in our analysis has been less than 1 yr. The results of conventional chemotherapy in the treatment of accelerated phase CML are disappointing. If a suitable donor is available allogeneic BMT should be performed without delay in patients with AP.


Subject(s)
Leukemia, Myeloid, Accelerated Phase/therapy , Adolescent , Adult , Age Factors , Bone Marrow Transplantation , Female , Humans , Leukemia, Myeloid, Accelerated Phase/drug therapy , Leukemia, Myeloid, Accelerated Phase/mortality , Male , Middle Aged , Retrospective Studies , Survival Rate , Transplantation, Homologous , Treatment Outcome
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