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A Leviton

Publications and source records attributed to A Leviton.

At least 73 records · Page 4Linked to original sources
PubMed1995

Age-related changes in diagnoses, histological features, and survival in children with brain tumors: 1930-1979. The Childhood Brain Tumor Consortium.

In the Childhood Brain Tumor Consortium database, the proportions of older children (> or = 11 yr) with pilocytic astrocytomas, fibrillary astrocytomas, and ependymomas significantly increased (P < 0.05) over the 50 years (1930-1979) of the study. The increased proportions of pilocytic astrocytomas occurred whether the tumors were located in the supratentorial or infratentorial compartments. The increases in fibrillary astrocytomas and ependymomas were found only within the supratentorial tumor location. Some histological features found in pilocytic astrocytomas (e.g., Rosenthal fibers, granular bodies, and very low cell density) were more likely to be found in older children. Other histological features were also more likely to be found in older children (e.g., parenchymal calcification, intertwined fascicles, intermediate and large-size nuclei, pleomorphic, elongated, or irregular nuclei, prominent nucleoli, multinucleated cells, thick hyaline blood vessels, hemosiderin, and parenchymal and perivascular lymphocytes). The probability of 5-year survival for young children with supratentorial ependymomas remained at approximately 0.4 in contrast to that for young children with infratentorial ependymomas, for whom it improved, but without significant linear trend. The probability of 5-year survival for both younger and older children with primitive neuroectodermal tumors (medulloblastomas) improved, but without significant linear trend. The changes in the proportions of childhood brain tumors and histological features occurred without similar changes in the proportions of older and younger children in the cities involved between 1930 and 1979. These changes were so distinctive as to raise the possibility of significant shifts in environmental exposures in younger and older children over the 50 years of this study.

Adolescent↗
PubMed1995

Maternal metabolic control and risk of microcephaly among infants of diabetic mothers.

OBJECTIVE: To measure the incidence of microcephaly among infants of diabetic mothers (IDM) and assess its relationship to metabolic control during pregnancy. RESEARCH DESIGN AND METHODS: Head circumference data for 556 consecutive live-born singleton infants of women with insulin-requiring diabetes antedating pregnancy delivered between 28 and 40 weeks of gestation and the results of 3,242 HbA1 determinations collected during their pregnancies were examined. RESULTS: There were fewer head circumferences at or below the 3rd percentile and more at or above the 97th percentile than expected. Head circumference was not related to maternal metabolic control as documented by the HbA1 values. CONCLUSIONS: The less-than-expected incidence of microcephaly observed in this patient population probably reflects the well-known tendency of IDM toward macrosomia.

Adult↗
PubMed1994

The role of family history in risk of childhood brain tumors.

BACKGROUND: Although brain tumors are the second most frequent malignancy in children, relatively little is known about the role of family history in risk of these tumors. METHODS: Children under the age of 18 years (n = 361) in whom primary brain tumors were diagnosed were identified from eight United States population-based Surveillance, Epidemiology, and End Results registries and compared to matched controls (n = 1083) identified by random-digit dialing. Information regarding family history of birth defects or tumors was obtained, along with data on other potential risk factors, from interviews with the mothers and fathers of the index children. RESULTS: No significant differences were found in family history of epilepsy. However, moderate elevations in risk were observed for a history of birth defects in maternal relatives, particularly for female propositi. Significantly more mothers (odds ratio [OR] = 1.63, 95% confidence limits [CL] = 1.03, 2.57) and maternal female relatives (OR = 2.15, 95% CL = 1.14, 4.06) of cases than of controls were reported to have had birth defects. History of birth defects in maternal relatives was particularly associated with childhood brain tumors of "other" (not astrocytoma or medulloblastoma) histologic type (OR = 2.37, 95% CL = 1.25, 4.53) and infratentorial tumors (OR = 1.76, 95% CL = 1.06, 2.93). Slight excesses of tumors were observed in paternal relatives of children with astrocytomas (OR = 1.43, 95% CL 0.93, 2.20) or with infratentorial tumors (OR = 1.46, 95% CL 0.97, 2.20). Risk of childhood brain tumors did not increase with the number of relatives affected with brain tumors, breast cancer, leukemia or lymphoma, soft tissue sarcomas, or all of these tumor types combined (the Li-Fraumeni syndrome). CONCLUSIONS: These findings suggest a modest increase in risk of childhood brain tumors associated with maternal family history of birth defects. Family history of tumors does not appear to contribute appreciably to an increased risk of brain tumors in children.

Adolescent↗
PubMed1994

Cerebral palsy.

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Cerebral Palsy↗
PubMed1994

Pre- and postnatal lead exposure and behavior problems in school-aged children.

The association between early lead exposure and later problem behaviors was evaluated prospectively in a cohort of 8-year-old children born during a 12-month period at one hospital. Lead levels in umbilical cord blood (means = 6.8 micrograms/dl, SD = 3.1) and the dentin of a shed deciduous tooth (means = 3.4 micrograms/g, SD = 2.4) provided measures of prenatal and postnatal exposure, respectively. Ratings on the Teacher Report Form of the Child Behavior Profile provided information about children's problem behaviors. Cord blood lead level was not associated with the overall prevalence or nature of problem behaviors. In both crude and adjusted analyses, tooth lead level was significantly associated with total problem behavior scores (approximately 2 points in T score per log unit increase in tooth lead). Significant tooth lead-associated increases in both internalizing and externalizing scores were also observed (approximately 1.5 points in T score per log unit increase). Weaker associations were noted between tooth lead level and the prevalence of "extreme" problem behavior scores. The extent to which these associations reflect residual confounding is uncertain. These data suggest, however, that social and emotional dysfunctions are correlates and may be expressions of increased lead exposure.

Child↗
PubMed1994

Histologic feature reliability in childhood neural tumors. Childhood Brain Tumor Consortium.

We studied intraobserver reproducibility in recognizing the presence or absence of 57 histologic feature or patterns in a random subset of tumors (822) from the Childhood Brain Tumor Consortium database. The study protocol maximized consistency of the observer. We found that only six histologic features had high (> or = 0.75) reliability estimates while a large number had intermediate estimates of 0.50-0.74. Supratentorial or infratentorial tumor location sometimes altered reliability. Reliability estimates were unacceptable for certain histologic features often used as diagnostic criteria, descriptors of tumor characteristics, or markers of anaplasia. We hypothesize that low reliability reflects, in part, the need for more specific operational definitions, particularly those with subjective boundaries (e.g. granular bodies) may also contribute to low reliability. We also show that the kappa statistic, a commonly used measure of reliability, is inappropriate for very common or uncommon histologic features (e.g. features at the extremes of prevalence in the study cases) and we offer a simple empiric method for determining when an alternative measure, the Jaccard statistic, is appropriate.

Brain Neoplasms↗
PubMed1994

Headache recurrence in pregnant women with migraine.

The goal of this study was to evaluate to what extent pregnancy influences headache recurrence in women with a diagnosis of migraine at, or before, their first prenatal visit. Data from the large, prospective Collaborative Perinatal Project of 55,000 pregnancies were reviewed. Less than 2% of women in the sample of first study pregnancies were considered to have migraine at their initial prenatal visit (n = 508). Of the 484 women with a complete data set, 17% experienced complete cessation of headache throughout pregnancy and another 62% experienced two or fewer headaches in the third trimester. These observations lead to the conclusion that many migraineurs (79% in this sample) experience improvement in headache recurrence during pregnancy. Only 21% experienced no improvement at all. No demographic or obstetrical factor was associated with headache improvement.

Female↗
PubMed1994

Correlates of decaffeinated coffee choice.

We sought to identify the illness risk factors associated with consumption of decaffeinated coffee in a sample of 2,677 adults. Women who drank decaffeinated coffee exclusively were more likely than other women to consume vitamin supplements and cruciferous vegetables, to use seat belts routinely, and to exercise regularly. Among men, those who drank decaffeinated coffee exclusively were more likely than others to have a low body mass index and to consume a low-fat diet and cruciferous vegetables. We conclude that people who drink decaffeinated coffee differ from others in ways that might provide information about the risk of illnesses.

Adult↗
PubMed1993

Parental smoking and risk of childhood brain tumors.

Data from a large, population-based, case-control study were analyzed to assess the role of parental smoking in childhood brain tumors. Parents of 361 cases, newly diagnosed between January 1, 1977 and December 31, 1981 and ascertained from eight Surveillance, Epidemiology, and End Results (SEER) program registries, and 1,083 controls had been interviewed. No significant differences in risks were found to be associated with maternal or paternal smoking at any time (odds ratio (OR) = 0.92 for mothers and 1.06 for fathers), during the year of birth of the child (which included both the prenatal and postnatal periods) (ORs = 0.84 for < 1 pack/day and 1.0 for > or = 1 pack/day for mothers, and 0.68 for < 1 pack/day and 1.07 for > or = 1 pack/day for fathers), or 2 years before the child was born, i.e., the pre-conception period (ORs = 0.75 for < 1 pack/day and 1.01 for > or = 1 pack/day for mothers, and 0.90 for < 1 pack/day and 1.15 for > or = 1 pack/day for fathers). Mothers were also specifically asked if they smoked during the pregnancy, and no association was found compared with never smokers (OR = 1.08, 95% confidence interval (CI) 0.80-1.45) or for ever-smokers who continued to smoke during pregnancy compared with those who stopped smoking during pregnancy (OR = 1.15, 95% CI 0.75-1.78). Finally, no significant increase in risk of brain tumors was found for the child's passive exposure to parental smoking during the period from birth to diagnosis of the brain tumor in the case. The lack of an effect of parental smoking was observed for both the major histologic types and locations of brain tumors. These findings and those from earlier studies provide no support for the hypothesis that parental cigarette smoking influences the risk of brain tumors in children.

Adult↗
PubMed1993

Pre- and postnatal low-level lead exposure and children's dysfunction in school.

The contributions of pre- and postnatal low-level lead exposures to the risk of learning problems were evaluated among 1923 children who were born in one Boston hospital in 1979-1980 and followed to age 8 years. In this relatively privileged group, more than 20% of the children had a mother with some formal postgraduate education. Prenatal lead exposure was estimated with a measurement of umbilical cord blood lead content, and postnatal lead exposure was approximated with measurement of lead in the dentin of an exfoliated deciduous tooth. Information about potential confounders and effect modifiers was obtained from maternal interview shortly after delivery and from a mailed questionnaire completed and returned when the child was approximately 6 years old. An assessment of each child's function in school was provided by the teacher, who completed a questionnaire near the end of the school year in which the child reached the age of 8 years. We considered a learning problem to be related to lead exposure if its adjusted prevalence increased with each loge increase in lead, and if the adjusted prevalence was elevated among children with high levels (i.e., approximating the highest decile) of umbilical cord blood lead (i.e., > or = 10 micrograms/dl) or dentin lead (i.e., > or = 5 micrograms/g). Girls with elevated umbilical cord blood lead levels were more likely than their peers to be dependent and inpersistent and to display an inflexible and inappropriate approach to tasks (defined as the "tasks" cluster). Boys with elevated umbilical cord blood lead levels were more likely than others to have difficulty with both simple directions and sequences of directions. Among girls, elevated deciduous tooth dentin lead content was associated with reading and spelling difficulties, the tasks cluster, and with "not functioning as well as peers." Elevated dentin lead levels were not overrepresented among boys with any of the assessed learning clusters. These findings are consistent with the inference that lead levels still prevalent among children (i.e., blood < 15 micrograms/dl) are associated with some learning problems in girls.

Child↗
PubMed1993

Relationships between serial blood lead levels and exfoliated tooth dentin lead levels: models of tooth lead kinetics.

Because bones and permanent teeth accumulate lead, exfoliated deciduous teeth have been utilized as retrospective markers of cumulative exposure in epidemiological surveys. In this paper we describe four models of lead uptake by the coronal dentin of shed primary teeth, each with different assumptions and ramifications. Each model is characterized by different relationships between blood lead at several ages and tooth lead. Values observed in our cohort of normal Boston children are most compatible with models positing the largest lead contribution coming at older ages (i.e., closer to age at exfoliation). Characteristics of models incompatible with our data include (1) lead deposition only during initial calcification and (2) no loss or resorption of lead.

Dentin↗
PubMed1993

The Boston Teacher Questionnaire. 1. Definition of syndromes.

To obtain information about the academic function of 9-year-old children from their school teachers, we created a short, forced-choice questionnaire that asked about the child's knowledge and use of arithmetic tables, reading, spelling, persistence at tasks, flexibility of approach, ability to function independently, distractibility, daydreaming, impulsivity and overexcitability, hyperactivity, and ability to follow simple and sequential directions. Questionnaires were collected from the teachers of 3451 white children whose mothers had enrolled in the National Collaborative Perinatal Project. Six syndromes in girls and five in boys were identified by both cluster and factor analyses of these data. Common to both sexes were five syndromes we labeled arithmetic, tasks (ie, impersistent/dependent/inflexible), reading, attention, and hyperactive. A syndrome characterized by difficulty following directions was seen in girls only. The prevalence of these syndromes ranged from a low for hyperactivity of 2.3 per 100 girls to a high for the attention syndrome of 27.6 per 100 boys. The congruent results obtained with clustering and factor analysis, and the agreement between the observed prevalence of syndromes and prior expectations suggests that the Boston Teacher Questionnaire, as this instrument is called, identifies learning problems in 9-year-old children.

Attention Deficit Disorder with Hyperactivity↗
PubMed1993

The Boston Teacher Questionnaire. 2. Assessments of validity.

We assessed the validity of the Boston Teacher Questionnaire in a sample of 3451 9-year-old children. Those identified by the questionnaire as having a learning difficulty syndrome were compared to those without any characteristic of that syndrome. The validity reference measures were individually administered neuropsychological assessments at age 7 years and a group-administered reading achievement test at age 9 years. Girls and boys with the reading syndrome had much lower reading scores at age 9 years than did their peers. Boys, but not girls, with the arithmetic syndrome were much more likely than their peers to have arithmetic scores more than one grade below the expected level at age 7 years. Girls and boys with the tasks syndrome, characterized by impersistence, dependence, and inflexibility, were more likely than those without any features of the syndrome to be classified as having little or no goal orientation by a neuropsychologist who assessed the children in an office setting. Similarly, the neuropsychologist was much more likely than expected to have classified children with the attention syndrome as having a short attention span, and to have classified boys, but not girls, with the hyperactivity syndrome as having an unusual/extreme level and nature of overactivity. Children with any syndrome were more likely than others to have low scores on components of the Wechsler Intelligence Scale for Children, items of the Bender-Gestalt Test that assessed integration and distortion, and measures of reading comprehension. We conclude that the Boston Teacher Questionnaire validly identifies children with learning problems.

Attention Deficit Disorder with Hyperactivity↗
PubMed1993

The Boston Teacher Questionnaire. 3. A reassessment.

The prevalence of different types of dysfunction in school was assessed with the Boston Teacher Questionnaire, completed for 1923 children born 8 years earlier in a university-affiliated maternity hospital. Cluster analyses of 15 items on the questionnaire resulted in six two-item clusters and one three-item cluster that were identical for girls and boys. We identified children as having a syndrome if they possessed all features of the cluster-defined syndrome. The most prevalent syndrome, consisting of both daydreaming and distractibility items, occurred in 18.5% of boys and 11.5% of girls. Boys were also more likely than girls to be identified as having the reading syndrome (11.6% and 7.7%, respectively), the hyperactivity/impulsivity syndrome (6.1% and 1.5%), and the syndrome characterized by frustration intolerance and peer problems (9.5% and 4.0%). The prevalences of the remaining three syndromes were similar in both sexes (arithmetic, 11.3% and 10.3%; difficulty following instructions, 5.1% and 4.7%; and the tasks syndrome [characterized by impersistence/dependence/inflexibility], 5.5% and 5.4%). More than 40% of boys and girls with one syndrome also had another. The lower prevalences in this sample than in an earlier-born sample assessed with the same instrument were confined to boys. Reasons for this temporal decrease in one sex only remain obscure. Girls with the reading syndrome were 10 times more likely, and boys with the reading syndrome were five times more likely, than their peers to receive special services and to have repeated a grade.

Attention Deficit Disorder with Hyperactivity↗
PubMed1993

Antenatal corticosteroids appear to reduce the risk of postnatal germinal matrix hemorrhage in intubated low birth weight newborns.

OBJECTIVE: To determine to what extent the reduced risk in preterm newborns of intracranial hemorrhage attributed to antenatal corticosteroids (ANCS) reflects reductions in the incidence of respiratory distress and its correlates. METHODS: In a sample of 239 very low birth weight newborns recruited for a clinical trial of phenobarbital prophylaxis of subependymal/intraventricular hemorrhage, we explored the relationship between ANCS, the occurrence of germinal matrix hemorrhage (GMH) that first became evident after the 12th postnatal hour, and putative intervening variables such as acidosis, elevated peak inspiratory pressure, pneumothorax-pulmonary interstitial emphysema, and elevated continuous positive airway pressure. RESULTS: In multivariate models adjusting for confounders, newborns exposed to ANCS were at approximately one third the risk of GMH experienced by newborns not exposed to a full course of ANCS. The additions of measures and correlates of respiratory distress severity to these models did not change the GMH risk associated with ANCS. CONCLUSION: The GMH-protective effect of ANCS does not appear to be a consequence of enhanced pulmonary maturation.

Cerebral Hemorrhage↗