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Biomedical subjects

J D Beck

Publications and source records attributed to J D Beck.

At least 19 recordsLinked to original sources

Biased distribution of chromosomal breakpoints involving the MLL gene in infants versus children and adults with t(4;11) ALL.

Derivative chromosomes of 40 patients diagnosed with t(4;11) acute lymphoblastic leukemia (ALL) were analysed on the genomic DNA level. Chromosomal breakpoints were identified in most cases within the known breakpoint cluster regions of the involved MLL and AF4 genes. Due to our current knowledge of the primary DNA sequences of both breakpoint cluster regions, specific features were identified at the chromosomal fusion sites, including deletions, inversions and duplications of parental DNA sequences. After separation of all t(4;11) leukemia patients into two age classes (below and above 1 year of age), the analysis of chromosomal fusion sites revealed significant differences in the distribution of chromosomal breakpoints and led to the definition of two hotspot areas within the MLL breakpoint cluster region. This may point to the possibility of different age-linked mechanisms that were leading to t(4;11) chromosomal translocations.

Adult↗

Recurrent disseminated retinoblastoma in a 7-year-old girl treated successfully by high-dose chemotherapy and CD34-selected autologous peripheral blood stem cell transplantation.

A localized retinoblastoma of the left eye in a 7-year-old girl, was treated by enucleation. She received no additional therapy. Four months later, metastases of retinoblastoma in the lymph nodes, bone and bone marrow were diagnosed. Relapse chemotherapy consisting of three courses of vincristine, cyclophosphamide, etoposide and carboplatin led to a second complete remission. Subsequent high-dose chemotherapy with thiotepa, etoposide and carboplatin and autologous stem cell transplantation with CD34-selected stem cells were successful, with no adverse effects. No radiotherapy was given and the girl remains in continuous second remission with a follow-up of more than 4 years.

Antigens, CD34↗

Humoral immunity against diphtheria, tetanus and poliomyelitis after antineoplastic therapy in children and adolescents--a retrospective analysis.

Serum antibodies against diphtheria- and tetanus-toxin were measured in 71 children and against poliomyelitis viruses 1-3 in 65 children and adolescents 0-18 months after cessation of antineoplastic therapy. Non or marginally protective serum titers were found in 62% of patients against diphtheria, in 18% of patients against tetanus and in 72% of patients against one or more poliomyelitis virus serotypes. Of these patients, 55%, 46% and 75% were immunized adequately according to age against diphtheria, tetanus and poliomyelitis, respectively. In 50% or more of patients a lack of protective immunity against diphtheria, tetanus and poliomyelitis was found which could not be explained by an inadequate immunization status. This suggests that other factors (e.g. influence of underlying illness, antineoplastic therapy or both on lymphocytes) might be responsible for these findings and this deserves further investigation. Measurement of serum antibodies against vaccine-preventable illnesses and consecutive booster immunizations are an essential part of long-term follow up in pediatric patients after antineoplastic therapy.

Adolescent↗

Combination antihypertensive drugs: recommendations for use.

The recommendation for first-line therapy for hypertension remains a beta blocker or diuretic given in a low dosage. A target blood pressure of less than 140/90 mm Hg is achieved in about 50 percent of patients treated with monotherapy; two or more agents from different pharmacologic classes are often needed to achieve adequate blood pressure control. Single-dose combination antihypertension therapy is an important option that combines efficacy of blood pressure reduction and a low side effect profile with convenient once-daily dosing to enhance compliance. Combination antihypertensives include combined agents from the following pharmacologic classes: diuretics and potassium-sparing diuretics, beta blockers and diuretics, angiotensin-converting enzyme (ACE) inhibitors and diuretics, angiotensin-II antagonists and diuretics, and calcium channel blockers and ACE inhibitors.

Adrenergic beta-Antagonists↗

Analysis strategies for longitudinal attachment loss data.

The purpose of this invited review is to describe and discuss methods currently in use to quantify the progression of attachment loss in epidemiological studies of periodontal disease, and to make recommendations for specific analytic methods based upon the particular design of the study and structure of the data. The review concentrates on the definition of incident attachment loss (ALOSS) and its component parts; measurement issues including thresholds and regression to the mean; methods of accounting for longitudinal change, including changes in means, changes in proportions of affected sites, incidence density, the effect of tooth loss and reversals, and repeated events; statistical models of longitudinal change, including the incorporation of the time element, use of linear, logistic or Poisson regression or survival analysis, and statistical tests; site vs person level of analysis, including statistical adjustment for correlated data; the strengths and limitations of ALOSS data. Examples from the Piedmont 65+ Dental Study are used to illustrate specific concepts. We conclude that incidence density is the preferred methodology to use for periodontal studies with more than one period of follow-up and that the use of studies not employing methods for dealing with complex samples, correlated data, and repeated measures does not take advantage of our current understanding of the site- and person-level variables important in periodontal disease and may generate biased results.

Disease Progression↗

Growth hormone deficiency in one of two siblings with Fanconi's anaemia complementation group FA-D.

Fanconi's anaemia (FA) shows great variability in phenotypic symptoms. We report on two FA siblings of German ancestry with the very rare form of the complementation group FA-D. Both presented with a similar phenotype and mild disease severity but with different growth. In the sister, growth velocity was normal, puberty and menarche occurred spontaneously. Her final height was within her parental target height. The younger brother had a reduced growth velocity, height SDS values below -5.5 SDS, a markedly retarded bone age, and delayed puberty. At the age of 12.9 years, growth hormone deficiency (GHD) was diagnosed and treatment with growth hormone was initiated. Our cases emphasize the heterogeneity of symptoms in FA even in siblings with the same genotype. In FA-children with severe growth retardation, GHD must also be considered.

Abnormalities, Multiple↗

Factors associated with periodontitis in an HIV-infected southeast USA study.

OBJECTIVES: To determine the relationship of immunosuppression with measures of probing pocket depth (PPD), recession (REC), and clinical attachment level (CAL) in an HIV-infected population from North Carolina (NC), a state in the southeastern United States (USA). DESIGN: Cross-sectional study of HIV-infected adults (n = 326) treated at the University of North Carolina Hospitals. Clinical medical record review and sociodemographic interview data were collected. Median age of study participants was 37 years (range 19-67). Males comprised 78% and Blacks 60%. Analyses were limited to those who were dentate (n = 316). MAIN OUTCOME MEASURES: Main outcomes were cases vs non-cases of notable PPD, REC, and CAL. Immunosuppression measured by CD4+ cell count microL was the exposure of interest. RESULTS: Defined cases of PPD (n = 148) were 2.6 (95% CI = 1.3, 5.3) times less likely to occur at CD4+ cells < 200 than non-cases, whereas, cases of REC (n = 94) were 2.8 (95% CI = 1.2, 6.6) times more likely to occur at that level of severe immunosuppression, controlling for confounders. CONCLUSION: Sub-groups of persons with HIV experience a high burden of periodontitis where notable severity and extent of PPD, CAL, and REC were clearly evident at different stages of immunosuppression.

AIDS-Related Opportunistic Infections↗

Gonadotrophin-independent puberty in a boy with a beta-HCG-secreting brain tumour.

We report on a short-statured boy in whom therapy with recombinant human growth hormone was initiated at the age of 9.7 years for assumed idiopathic growth hormone deficiency. On recombinant human growth hormone, height improved from -1.9 (standard deviation score) to -0.9 within 1 year, and the patient entered puberty spontaneously at 10.7 years. At 11.6 years he showed low morning cortisol and thyroxine levels, but was otherwise well. He showed an inconspicuous growth, and puberty progressed adequately until the age of 13.4 years, when he developed signs of an increased intracranial pressure, and a suprasellar choriocarcinoma was diagnosed. This case confirms the fact that beta chorionic gonadotrophin secreting tumours will not be diagnosed by the characteristic clinical manifestation of gonadotrophin-independent puberty if they occur at a time when normal puberty is expected. Particularly, it raises the question of how often the CNS should be re-evaluated by magnetic resonance imaging in children with growth hormone deficiency and normal initial neuroradiological imaging, when they develop additional hormonal deficiencies but no other clinical symptoms of an intracranial process.

Adolescent↗

Acute-phase inflammatory response to periodontal disease in the US population.

Moderate elevation of serum C-reactive protein (CRP) is a risk factor for cardiovascular disease among apparently healthy individuals, although factors that create this inflammatory response in the absence of systemic illness have not been clarified. This study aimed to: (1) evaluate associations among periodontal disease, established risk factors for elevated CRP, and CRP levels within the US population; and (2) determine whether total tooth loss is associated with reduced CRP. Data were obtained from the third National Health and Nutrition Examination Survey. A random sample of the US population was interviewed in their homes and examined at mobile examination centers. CRP was quantified from peripheral blood samples and analyzed as a continuous variable and as the prevalence of elevated CRP (> or = 10 mg/L). Some 12,949 people aged 18+ years who had periodontal examinations and an additional 1,817 edentulous people aged 18+ years were included in the analysis. Dentate people with extensive periodontal disease (> 10% of sites with periodontal pockets 4+ mm) had an increase of approximately one-third in mean CRP and a doubling in prevalence of elevated CRP compared with periodontally healthy people. Raised CRP levels among people with extensive periodontal disease persisted in multivariate analyses (P < 0.01), with established risk factors for elevated CRP (diabetes, arthritis, emphysema, smoking, and anti-inflammatory medications) and sociodemographic factors controlled for. However, CRP levels were similarly raised in edentulous people. Furthermore, the established risk factors for elevated CRP modified relationships between oral status and CRP levels. Periodontal disease and edentulism were associated with systemic inflammatory response in the US population, most notably among people who had no established risk factors for elevated CRP.

Acute-Phase Reaction↗

Non-Hodgkin's lymphoma in pediatric patients with chromosomal breakage syndromes (AT and NBS): experience from the BFM trials.

BACKGROUND: Lymphoma and leukemia are the commonest malignant diseases in patients with chromosomal breakage syndromes and immunodeficiency (Ataxia teleangiectasia (AT) and Nijmegen breakage syndrome (NBS)). With improved management of infections, malignant disease is more frequently diagnosed and has become one of the commonest causes of death in pediatric AT and NBS. PATIENTS AND METHODS: In three consecutive multicenter therapy trials for pediatric non-Hodgkin's lymphoma (NHL) (NHL-BFM), 1569 patients with newly diagnosed NHL have been registered between 1986 and 1997. Nine patients with AT (n = 5) and NBS (n = 4) were identified and analysed. RESULTS: Median age of patients with AT and NBS at diagnosis of NHL was nine years. NHL-entities differed from non-AT/NBS-patients: diffuse large B-cell lymphomas, n = 7 (78%); ALCL, n = 1; lymphoblastic T-cell lymphoma, n = 1. Cervical nodes, paranasal sinuses and epipharynx were the sites most frequently involved. Stages were: I and II in three patients, III in five and IV in one patient. All patients received polychemotherapy according to tumor-entity and stage, none received radiation. Dose reductions according to individual tolerance concerned mainly ethotrexate, alkylating agents and epipodophyllotoxines. One patient died of toxic complications, two patients relapsed and died, one patient suffered from second malignancy. Five of nine patients are in 1. CCR after a median follow-up of five years. CONCLUSIONS: Patients with AT and NBS suffer from rare entities of pediatric NHL. Curative treatment is possible and should be attempted. Intensity of therapy should be adjusted to individual risk factors and tolerance. Alkylating agents, epipodophyllotoxines should be omitted, dose of MTX should be limited to 1 g/m2. Further cooperative trials using standardized approaches are required.

Adolescent↗

Rapid isolation of chromosomal breakpoints from patients with t(4;11) acute lymphoblastic leukemia: implications for basic and clinical research.

Chromosomal translocations t(4;11)(q21;q23) are associated with a group of acute lymphoblastic leukemias with very poor prognosis. From the complete sequences of the breakpoint cluster regions of the human MLL and AF-4 translocation partner genes, a novel set of 66 oligonucleotides that facilitates the rapid identification of translocation breakpoints by PCR analysis of genomic DNA was designed. For each breakpoint, a pair of optimally snited primers can be assigned, which improves the monitoring of the disease during treatment. Comparison of the breakpoints with the corresponding parental sequences also contributes to our better understanding of the illegitimate recombination events leading to these translocations.

Alu Elements↗

[Disorders of endocrine function after brain tumor therapy in childhood].

BACKGROUND: Advances in the therapy of malignant brain tumors in children have led to a significant improvement in survival rates over the last few decades. As a result, the recognition and treatment of late effects have become more important. In addition to secondary tumors and deficiencies in cognitive and intellectual skills, the resulting endocrine disturbances play an important role. METHOD: Own data and literature review. RESULTS: Deviations from the normal growth hormone secretion are usually recognized first and are most common, and have already been observed after conventional whole brain irradiation with 18 Gy. With some delay, other hypothalamo-pituitary deficiencies may occur, including panhypopituitarism. Puberty may come too early or too late or may not appear at all. Girls in particular, frequently experience an early and rapid pubertal development after brain tumor therapy, which may lead to further reduction in height due to an accelerated bone maturation. Functional disturbances of the thyroid and adrenal glands due to hypothalamic or pituitary deficiency are less common, and usually seen only after a radiation dose of over 40 Gy. CONCLUSION: Survivors of childhood brain tumors must be considered as long-term survivors, in whom the first therapy-induced long-term side effects appear almost immediately after the end of therapy. Maximum quality of life for the individual patient can only be achieved by long-term care and close cooperation of specialists in the different medical disciplines involved.

Brain↗