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J D Buckley

Publications and source records attributed to J D Buckley.

At least 73 records · Page 4Linked to original sources
PubMed1991

High-resolution linkage mapping for susceptibility genes in human polygenic disease: insulin-dependent diabetes mellitus and chromosome 11q.

Insulin-dependent diabetes mellitus (IDDM) has a complex pattern of genetic inheritance. In addition to genes mapping to the major histocompatibility complex (MHC), several lines of evidence point to the existence of other genetic susceptibility factors. Recent studies of the nonobese diabetic mouse (NOD) model of IDDM have suggested the presence, on mouse chromosome 9, of a susceptibility gene linked to the locus encoding the T-cell antigen, Thy-1. A region on human chromosome 11q is syntenic to this region on mouse chromosome 9. We have used a set of polymorphic DNA markers from chromosome 11q to investigate this region for linkage to a susceptibility gene in 81 multiplex diabetic pedigrees. The data were investigated by maximization of lod scores over genetic models and by multiple-locus affected-sib-pair analysis. We were able to exclude the presence of a susceptibility gene (location scores less than -2) throughout greater than 90% of the chromosome 11q homology region, under the assumption that the susceptibility factor would cause greater than 50% of affected sib pairs to share two alleles identical by descent. Theoretical estimates of the power to map susceptibility genes with a high-resolution map of linked markers in a candidate region were made, using HLA as a model locus. This result illustrates the feasibility that IDDM linkage studies using mapped sets of polymorphic DNA markers have, both for other areas of the genome in IDDM and for other polygenic diseases. The analytic approaches introduced here will be useful for affected-sib-pair studies of other complex phenotypes.

Chromosome Mapping↗
PubMed1990

Occupations of parents of children with retinoblastoma: a report from the Children's Cancer Study Group.

A matched case-control study was conducted by the Children's Cancer Study Group to investigate the role of parental occupation in the etiology of sporadic heritable and nonheritable retinoblastoma. Eligible cases were those patients with retinoblastoma diagnosed in 1982-1985 at any of the Children's Cancer Study Group member hospitals. Telephone interviews of 201 parents of cases and their pair-matched controls selected by random digit dialing were completed. Of the 201 cases, 19 were familial, 67 were sporadic heritable, and 115 were nonheritable. The 19 familial cases were excluded from the analysis. Paternal employment in the military [odds ratio (OR) 2.8, 95% confidence interval (CI) 1.1-8.8, P = 0.04] and in the metal industry (OR infinity, 95% CI 1.4-infinity, P = 0.02) was associated with sporadic heritable retinoblastoma (N = 67). For nonheritable retinoblastoma (N = 115), a significant association was observed for a job cluster consisting mostly of welders and machinists (OR 4.0, 95% CI 1.1-22.1, P = 0.04). Occupations of maternal grandparents were also studied and an association was observed with farming and nonheritable retinoblastoma (OR 10.0, 95% CI 1.4-433, P = 0.02). Many comparisons were made and the number of significant findings did not exceed that expected by chance. Thus, the results need to be interpreted very cautiously. However, the findings related to metal exposure corroborate observations on other childhood cancers.

Case-Control Studies↗
PubMed1990

The role of timing of high-dose cytosine arabinoside intensification and of maintenance therapy in the treatment of children with acute nonlymphocytic leukemia.

The Children's Cancer Study Group instituted a pilot study to investigate the use of high doses of cytosine arabinoside (AraC) in the intensification phase of treatment for acute nonlymphocytic leukemia (ANLL). Patients achieving remission and not eligible for allogeneic bone marrow transplantation were treated with four doses of high-dose AraC and L-asparaginase. These drugs were repeated either on or after 28 days (q28 days), after recovery of hematologic parameters (for the first 49 patients entered onto this trial); or after 7 days (q7 days), despite dropping blood counts (for the last 53 patients enrolled). After completing an additional 3 months of intensification therapy, patients were then allocated by physician choice to either discontinue therapy or receive 18 28-day cycles of maintenance therapy, including the daily administration of 6-thioguanine. Despite three deaths associated with the toxicity of the aggressive (q7 days) AraC timing, patients receiving this approach demonstrated equal or better disease-free survival from the end of induction (55% versus 42% actuarially at 3 years [P = 0.52]). Maintenance therapy appeared to play no role in improving outcome for people who received the aggressive timing of AraC cycles. Fifty-nine percent were alive disease free actuarially at 3 years from the decision to not give maintenance therapy (n = 27) compared with 62% for those receiving maintenance therapy (n = 16; P = 0.49). On the other hand, patients who received the less aggressive AraC intensification timing (q28 days) had an improved survival rate if maintenance therapy was administered (n = 17) (65% versus 39% for patients not receiving maintenance therapy [n = 24] at 3 years [P = 0.07]). Maintenance therapy therefore may not improve outcome in patients receiving aggressive timing of high-dose AraC but may be important in less intensive postremission regimens in childhood ANLL.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Acute monoblastic leukemia: a unique subtype--a review from the Childrens Cancer Study Group.

The acute non-lymphocytic leukemias (ANLL) are generally treated as a homogeneous group. However, the literature is replete with articles alluding to distinctive features of acute monoblastic leukemia (AMoL). This review addresses the unique clinical, laboratory, epidemiological, and therapeutic features of AMoL. Leukemic monoblasts are distinguished from other cells in the myelocytic series by physical properties such as greater adhesiveness, deformability, and motility. Patients with AMoL often exhibit hyperleukocytosis, disseminated intravascular coagulation, and extramedullary involvement, particularly in the skin, gingiva, and central nervous system (CNS). AMoL occurs predominantly in adults over 40 and children under 10, fifty percent of whom are under 2 years of age at diagnosis. Its relatively common occurrence in infants parallels the high rate of proliferation of monocytes in that age group. Additionally, its occurrence in young children appears to be associated with in utero exposure to marijuana and parental exposure to pesticides and solvents. Therapeutic results are generally poor due to high rates of fatal complications during induction, induction failures, and frequent extramedullary and medullary relapses. This poor outcome is particularly noted in infants. Higher remission induction rates attained with epipodophyllotoxins and incorporation of bone marrow transplantation have not yet resulted in substantial improvement of long-term outcome. Recurrence of disease in the CNS is minimized by the use of intensive CNS presymptomatic treatment, usually incorporating irradiation. Our review suggests that unique and innovative treatment strategies are needed to improve outcome for patients with AMoL.

Adult↗
PubMed1990

Preferential retention of paternal alleles in human retinoblastoma: evidence for genomic imprinting.

The origins of the initial mutations in sporadic retinoblastoma were explored using polymorphic markers from chromosome 13q. The paternal chromosome was maintained in 3 of 3 informative bilateral tumors which had undergone reduction to homozygosity for regions of this chromosome. The paternal chromosome was maintained in 7 of 8 informative unilateral tumors which likewise demonstrated a reduction of homozygosity. These data are in contrast to previously published studies of chromosome retention in unilateral retinoblastoma [Dryja, T. P., Mukai, S., Petersen, R., Rapaport, J. M., Walton, D., and Yandel, D. W. Nature (Lond.), 339: 556-558, 1989; Zhu, Z., Dunn, J. M., Phillips, R. A., Goddard, A. D., Paton, K. E., Becker, A., and Gallie, B. L. Nature (Lond.), 340: 312-313, 1989] and provide the first evidence that genomic imprinting may play a role in this disease.

Alleles↗
PubMed1989

Pre- and postconception factors associated with sporadic heritable and nonheritable retinoblastoma.

A matched case-control study of retinoblastoma was conducted by the Children's Cancer Study Group (CCSG) to investigate the hypotheses that postconception exposures affect the risk of the nonheritable (post-zygotic origin) form of this disease and that preconception exposures affect the risk of the sporadic heritable (prezygotic origin) form. Eligible cases were those patients with retinoblastoma diagnosed in 1982-1985 at any of the CCSG member hospitals. Cases were classified as familial heritable, sporadic heritable, or nonheritable based on family history, tumor laterality, and cytogenetic analysis. Telephone interviews of parents of 201 cases and their pair-matched controls selected by random digit dialing were completed. Analysis of possible risk factors for the 67 sporadic heritable cases and the 115 nonheritable cases was performed. (The 19 familial cases were excluded). For the nonheritable group, gestational exposure to X-ray [odds ratio (OR) = 2.3, P = 0.08] and morning sickness medication (OR = 2.8, P = 0.02) and low maternal educational level (OR = 5.5, P = 0.03) were associated with increased risk; anemia (OR = 0.3, P = 0.02) and multivitamin use (OR = 0.4, P = 0.03) during pregnancy and periconceptional use of barrier contraceptive (OR = 0.1, P = 0.02) or spermicide (OR = 0.2, P = 0.02) were associated with decreased risk. In the sporadic heritable group, observations included a negative association with multivitamins during pregnancy (OR = 0.2, P = 0.02) and nonsignificant positive associations with preconception gonadal X-ray (maternal, OR = 2.0, P = 0.30; paternal, OR = 1.8, P = 0.42) and older parental age (case-control difference 1.0-1.2 years, P = 0.24-0.27). Many of the associations support study hypotheses, although the possibility of recall bias and chance findings suggest cautious interpretation.

Case-Control Studies↗
PubMed1989

A case-control study of risk factors for hepatoblastoma. A report from the Childrens Cancer Study Group.

Parents of 75 children with hepatoblastoma, registered with the Childrens Cancer Study Group, and 75 age-matched controls, who had been identified through random digit dialing were interviewed. No evidence was found to support the primary study hypotheses relating to hepatitis infection, maternal estrogen exposure, alcohol consumption, smoking, or potential sources of nitrosamines. Case mothers were more likely to report occupational exposure to metals (odds ratio [OR] = 8.0, P = 0.01), petroleum products (OR = 3.7, P = 0.03), and paints or pigments (OR = 3.7, P = 0.05). Metal exposures were commonly to welding or soldering fumes, and most occurred daily, before and during the index pregnancy. Petroleum product exposures were predominantly to lubricating oils or protective greases. The only significant paternal exposure was to metals (OR = 3.0, P = 0.01) and the risk with exposure to petroleum products was marginally significant (OR = 1.9, P = 0.06). These findings provide further evidence that occupational exposures may increase the risk of cancer in offspring.

Adult↗
PubMed1989

Occupational exposures of parents of children with acute nonlymphocytic leukemia: a report from the Childrens Cancer Study Group.

The Childrens Cancer Study Group conducted a case-control study of occupational exposures of parents of 204 children (under 18 yr of age) with acute nonlymphoblastic leukemia. The most consistent finding was an association of acute nonlymphoblastic leukemia risk with pesticide exposure. Controls matched by date of birth and race were obtained through random digit dialing. Odds ratio (OR) for paternal pesticide exposure in jobs held for longer than 1000 days was 2.7 (95% confidence interval, 1.0 to 7.0; trend, P = 0.06), and seven case mothers and no control mothers had prolonged exposure (trend, P = 0.008). Risk estimates for parental pesticide exposure were substantially increased for children under age 6 at diagnosis (OR for prolonged exposure to either parent = 11.4; trend, P = 0.003) and for those with myelomonocytic and monocytic subtypes (OR, 13.6; trend, P = 0.007). Moreover, there were significantly elevated risks for direct exposure of the child to pesticides in the household (OR for exposure most days = 3.5; trend, P = 0.04) and for maternal exposure to household pesticides at the time of pregnancy (eight case mothers versus no controls for exposure most days; trend, P = 0.05). Paternal exposures to solvents (OR, 2.1; P = 0.003) and petroleum products (OR, 2.4; P = 0.002) were reported more commonly for cases than controls. Other occupational exposures reported significantly more often by case parents were paternal exposure to plastics or lead and maternal exposure to paints and pigments, metal dusts, and sawdust. These data provide further evidence for a role of occupational risk factors in the etiology of childhood cancer.

Adolescent↗
PubMed1989

Maternal drug use and risk of childhood nonlymphoblastic leukemia among offspring. An epidemiologic investigation implicating marijuana (a report from the Childrens Cancer Study Group).

The Childrens Cancer Study Group conducted a case-control study designed to assess in utero and postnatal exposures in children with acute nonlymphoblastic leukemia (ANLL). Analyses were performed for reported maternal use of medications and drugs in the year preceding and during the index pregnancy of the 204 case-control pairs. An 11-fold risk (P = 0.003) was found for maternal use of mind-altering drugs just prior to or during the index pregnancy. Compared with ANLL cases not exposed to marijuana, exposed cases were significantly younger at diagnosis of ANLL (P less than 0.01) and were more often of the myelomonocytic and monocytic subtypes (P less than 0.01). Use of antinausea medication for more than 11 weeks was also associated with a significantly elevated relative risk of 2.81 and a dose-response relationship was noted (P = 0.05 for trend). These results suggest that maternal drug use of marijuana may have an etiologic role in childhood ANLL and may be specific for morphologically defined subgroups.

Adolescent↗
PubMed1989

Improvement in outcome for children with acute nonlymphocytic leukemia. A report from the Childrens Cancer Study Group.

The Childrens Cancer Study Group conducted four therapeutic studies on a total of 1006 children with acute nonlymphocytic leukemia from 1972 to 1983. This report describes the therapeutic strategies of these studies and examines trends in induction rates and long-term outcome over this period. The remission induction rate has changed from 58% in 1972 to 1975 to 80% for the period 1980 to 1983, and the induction mortality dropped from 20% to 6%. Four-year survival probabilities from time of diagnosis have almost doubled from 19% to 36%. Few deaths occurred more than 5 years after diagnosis: children surviving in first remission beyond 5 years had a 92% survival rate and an 86% relapse-free survival rate over the next 5 years. In contrast, median survival after a marrow relapse was less than 6 months and the 6-year survival probability was 4%. The leukocyte count was a significant prognostic factor, and although the mortality for infants was high initially, long-term survival was not decreased.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

Frequency of 13q abnormalities among 203 patients with retinoblastoma.

We studied peripheral blood lymphocyte karyotypes of 203 patients with retinoblastoma. Twelve (5.9%) had a constitutional chromosomal abnormality involving 13q, of whom six had unilateral and six had bilateral disease. Two patients had mosaic deletions, eight had nonmosaic deletions, one had a de novo translocation, and one had a 13q14 deletion and a de novo direct insertion (10;6). Of the total, 4.9% of unilateral and 7.5% of bilateral patients had 13q abnormalities. None of 19 familial retinoblastoma patients had a visible cytogenetic abnormality. The unilateral patients with 13q abnormalities represent prezygotically determined (potentially heritable) cases which would have been classified as postzygotic (sporadic) without cytogenetic analysis. The observed 1% frequency of mosaic deletions is lower than that previously reported.

Child↗
PubMed1989

Remission induction in children with acute non-lymphocytic leukemia using cytosine arabinoside and doxorubicin or daunorubicin: a report from the Childrens Cancer Study Group.

Four hundred ninety evaluable patients were treated on an induction regimen consisting of two to four courses of cytosine arabinoside plus an anthracycline. Overall, 78% of patients went into remission, 10% died during induction, and 12% were induction failures. For the first 152 patients, courses consisted of 7 days continuous infusion with cytosine arabinoside (Ara-C, 100 mg/m2) and 3 days of doxorubicin (30 mg/m2). Because of unacceptable toxicity, particularly for children less than 3 years of age, the anthracycline was changed to daunorubicin, and the doses of both induction drugs for children under 3 was reduced. For children aged 3 years and older the change in anthracycline was associated with a significant increase in induction failures (7% to 16%, P = .04) and a decrease in deaths (15% to 8%, P = .09). For younger children, for whom doses were also changed, the effect was greater; Mortality decreased from 29% to 1% (P less than .0001), and the remission induction rate increased from 66% to 88% (P = .005). The therapy modifications also influenced survival following remission induction: Daunorubicin-treated patients, aged 3 years and over, did significantly better than those given doxorubicin (P = .03), but the opposite was seen in younger children (P = .06). Gastrointestinal and skin toxicities and septicemia were significantly more common when doxorubicin was being used, but the extent of myelosuppression was similar for the two anthracyclines.

Age Factors↗
PubMed1989

Multiple sclerosis in mothers of children with acute lymphoblastic leukemia.

The Childrens Cancer Study Group used data from a self-administered questionnaire to compare the observed and expected frequencies of multiple sclerosis (MS) in the parents of 1,027 children with acute lymphoblastic leukemia (ALL), 2,053 parents of children with other cancers, and in parents of 838 children without cancer. There were significant excesses seen for mothers of children with ALL (relative risk, RR = 4.0, p = 0.02), but no excess was found for acute nonlymphoblastic leukemia or lymphoma. There was no increase risk of MS for the fathers of these children.

Adolescent↗
PubMed1988

Case-control study of gestational choriocarcinoma.

A multicentered case-control study of 75 women who had had gestational choriocarcinoma was conducted to investigate the role of reproductive and fertility factors as well as other potential risk factors in the development of this disease. Control women, identified through random digit dialing, were individually matched to cases by year of pregnancy, age at pregnancy, and geographical proximity of residence. Choriocarcinoma risk was decreased significantly as body mass index increased (P for trend = 0.03). Cases reported low-calorie dieting significantly less frequently than controls [odds ratio estimate (OR) = 0.50, P = 0.05] and were significantly less likely to participate in regular exercise (OR = 0.38, P = 0.004). Compared to women with a heavy menstrual flow, those with light menstruation had significantly elevated risk (OR = 6.69, P = 0.01). Menarche after age 12 was also associated with elevated risk of this disease (OR = 2.89, P = 0.003). There were significantly more pairs of dizygotic twins born to cases and their first degree relatives than to controls (12 case families with 13 sets of twins versus 3 sets in control families, OR = 6.36, P = 0.009). Cases were more likely to have married more than once (OR = 13.0, P less than 0.001), and infrequent intercourse was a significant risk factor (OR for weekly or less often was 3.00, P = 0.04). Risk estimates for postmolar choriocarcinoma were not significantly different from those for all other cases. These observations and some descriptive features of the disease suggest that hormonal factors, specifically below normal estrogen levels, may be associated with a disruption of normal ovulation and thus predispose to choriocarcinoma.

Adult↗
PubMed1984

The epidemiology of molar pregnancy and choriocarcinoma.

The available evidence suggests quite strongly that a hydatidiform mole arises as a consequence of production of a defective ovum. That the defect is maternal is implied by the risk associated with increasing maternal (but not paternal) age, by the recurrence in some women of multiple moles (even in one instance by different husbands), and by reports of familial aggregation of hydatidiform moles among sisters. The absence of maternal genetic material in most complete hydatidiform moles and the dispermic fertilization of some complete and most partial moles further suggests that the ovum is defective. The causes of defective or "blighted" ova are not known. The dramatic increase in risk with age, the smaller increase in young women, and the high incidence in women in parts of Asia must all be important clues. Consanguinity, malnutrition, racial (genetic) predisposition, oral contraceptives, and viral infections have been advanced as causative or contributory factors. Disorders of ovulation, with prolongation of the follicular phase or an inadequate luteal phase, may produce a suboptimum ovum. At some time after ovulation, when the viability of the ovum has become borderline, abnormal (e.g., dispermic) fertilization may become more likely. These and other speculations are being investigated in the detailed case-control studies of trophoblastic disease epidemiology, currently in progress.

ABO Blood-Group System↗
PubMed1984

Additive and multiplicative models for relative survival rates.

The relative survival rate is the ratio of the overall survival rate to that 'expected' for demographically similar individuals in a reference population. It is commonly used to estimate the effect of a particular disease on mortality, when the cause of death is not reliably known. The effect of the disease on the underlying hazards may be multiplicative or additive; the former case has been considered elsewhere but seems biologically less plausible than the latter. Both models are examined in this paper. The effect of the disease is assumed to be constant throughout the follow-up period, or to be piecewise constant within K follow-up intervals. Maximum likelihood estimates and related statistics are presented, as are simpler statistics based on moment estimators of the disease effect. The moment-based statistic for testing the homogeneity of r groups may be expressed as a sum of individual scores, which are shown to be closely related to the logrank scores when follow-up intervals are made arbitrarily small.

Adult↗