Half-life of polybrominated biphenyl in human sera.

Polybrominated biphenyl (PBB), a flame-retardant material, was introduced into the food chain in Michigan in 1973 due to a manufacturing and distribution mistake. Following public concern about the long-term health effects of PBB in humans, a cohort of PBB-exposed Michigan residents was assembled in 1975. We initiated this study to determine the half-life of PBB in human sera and to understand how continued body burden relates to the possible adverse health consequences of PBB exposure. To determine the half-life, eligible persons were selected from the cohort if they had at least two PBB measurements 1 year apart and had an initial level > or = 20 pbb. There were 163 persons who met the criteria with a median PBB level of 45.5 ppb. The estimated half-life is 10.8 years (95% CI, 9.2-14.7 years). The body burden of PBB in exposed persons will decrease only gradually over time. For persons with an initial level of 45.5 ppb of PBB, it will take more than 60 years for their PBB levels to fall below the current level of detection of 1 ppb.     

Antibody response to poliovirus immunization in childhood leukemia.

Polio antibody titers were determined in 29 children with ALL in various clinical stages, including a group of five patients in continuous remission for over five years and who, at the time of study, were off all therapy for at least six months. Regardless of the stage of disease, no detectable gamma M response was elicited. The five children described above displayed the same depressed response as did the other children with ALL. This strongly suggests an inherent defect in the immune system of these children with ALL unrelated to therapy.     

Chemotherapy in recurrent noncystic low-grade astrocytomas of the cerebrum in children

Six children with grade II astrocytomas were treated with combination chemotherapy consisting of 1,3 bis(2-chloroethyl) 1-nitrosourea (BCNU). Vincristine (VCR), intrathecal Methotrexate (i.t. MTX), and Dexamethasone. Of the children, 3 showed a partial remission, and 1 other showed clinical improvement. Our data suggest that chemotherapy is effective in low-grade astrocytomas, and there is now a need for larger trials in low-grade astrocytomas to document the role of chemotherapy accurately in these tumors. It is suggested that trials of chemotherapy as adjuvant to surgery and radiotherapy should be initiated.     

Blood mercury levels in US children and women of childbearing age, 1999-2000

Context  Humans are exposed to methylmercury, a well-established neurotoxin, through fish consumption. The fetus is most sensitive to the adverse effects of exposure. The extent of exposure to methylmercury in US women of reproductive age is not known. Objective  To describe the distribution of blood mercury levels in US children and women of childbearing age and the association with sociodemographic characteristics and fish consumption. Design and Setting  The 1999-2000 data from the National Health and Nutrition Examination Survey, a cross-sectional survey of the noninstitutionalized US population. Participants  In 1999-2000, 1250 children aged 1 to 5 years and 2314 women aged 16 to 49 years were selected to participate in the survey. Household interviews, physical examinations, and blood mercury levels assessments were performed on 705 children (56% response rate) and 1709 women (74% response rate). Main Outcome Measure  Blood concentration of total mercury. Results  Blood mercury levels were approximately 3-fold higher in women compared with children. The geometric mean concentration of total blood mercury was 0.34 µg/L (95% confidence interval [CI], 0.30-0.39 µg/L) in children and 1.02 µg/L (95% CI, 0.85-1.20 µg/L) in women. Geometric mean mercury levels were almost 4-fold higher among women who ate 3 or more servings of fish in the past 30 days compared with women who ate no fish in that period (1.94 µg/L vs 0.51 µg/L; P<.001). Conclusions  Measures of mercury exposure in women of childbearing age and young children generally fall below levels of concern. However, approximately 8% of women had concentrations higher than the US Environmental Protection Agency's recommended reference dose (5.8 µg/L), below which exposures are considered to be without adverse effects. Women who are pregnant or who intend to become pregnant should follow federal and state advisories on consumption of fish.      

Optimal use of L-asparaginase (NSC-109229) in acute lymphocytic leukemia

Between 1971 and 1974, 646 evaluable patients under 20 years of age with previously untreated acute lymphocytic leukemia were treated according to Cancer and Leukemia Group B (formerly Acute Leukemia Group B) Protocol 7111. On a random basis, they received a 10-day course of 1,000 units/kg/day of L-asparaginase before, during, or after a 3-week course of vincristine and corticosteroid. A control group received vincristine and corticosteroid for 4 weeks but no asparaginase. The overall complete remission rate was 85%, which was not altered significantly by any of the induction variables. Patients who received asparaginase for 10 days subsequent to vincristine and corticosteroid had a significantly longer complete remission duration with an estimated median of 45 months, compared to 20 months for the group receiving no asparaginase and 27 months for the other 2 asparaginase regimens. The beneficial effect of asparaginase was noted, irrespective of which 1 of the 2 intensification and maintenance programs the patients received. The 5-year projection indicates a complete remission rate of 50% for those patients receiving subsequent asparaginase as compared to 41% of those induced on other regimens in this study and thus is superior to the use of only vincristine and corticosteroid.     

Receptors for sheep erythrocytes (E) and erythrocyte-antibody-complement complexes (EAC) on the lymphoblasts of childhood acute lymphoblastic leukemia

Two cell-surface markers, rosette formation with sheep erythrocytes (E-rosette) as a T-cell marker and rosette formation with bovine erythrocyte-antibody-complement complex (EAC-rosette) as a B-cell marker were determined on peripheral blood lymphocytes and lymphoblasts from normal and 89 children with acute lymphoblastic leukemia (ALL). In the majority of the patients (12/15 untreated patients and 6/11 patients in relapse), lymphoblasts exhibited neither E- nor EAC-rosette formation. Lymphoblasts from one untreated patient with mediastinal mass displayed E-(50%) and EAC-rosette formation (15%). In 3 of 11 patients in relapse, lymphoblasts displayed an increase in EAC-rosette formation with progressive disease. In the remaining patients with active disease, a small and variable proportion of lymphoblasts expressed E and/or EAC-rosette formation. In 63 patients in remission, percentages of E- and/or EAC-rosette were similar (p > 0.05) to those of control. The results indicate a wide heterogeneity with respect to expression of lymphocyte membrane markers in lymphoblasts and in normal lymphocytes in patients with active ALL.     

Adjuvant adriamycin and cisplatin in newly diagnosed, nonmetastatic osteosarcoma of the extremity

Twenty-two patients with newly diagnosed nonmetastatic osteosarcoma of the extremity were treated with an adjuvant chemotherapeutic regimen consisting of Adriamycin (Adria Laboratories, Columbus, Ohio) and cisplatin. Fourteen of the 22 patients remain continuously disease free for 65+ to 113+ months, with a median time on study of 70+ months. The 72-month disease-free survival estimate is 64%. Pulmonary metastases occurred in six patients, an isolated stump recurrence was seen in one patient, and one patient had a local recurrence following a limb-salvage procedure. For those patients in whom pulmonary metastases developed, the onset was late in three of six, and the number of metastases was three or fewer in all patients. Two patients with pulmonary metastases and one with a stump recurrence have apparently been salvaged, thus resulting in a 77% 72-month survival. Toxicity observed in patients treated with this regimen was in keeping with previous reports. This chemotherapeutic regimen is effective in the adjuvant therapy of nonmetastatic osteosarcoma of the extremity. It should be incorporated into other adjuvant protocols in an effort to continue to improve the outcome in patients with osteosarcoma.