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T Greene

Publications and source records attributed to T Greene.

83 records · Page 5Linked to original sources

Utility and limitations of chromosome banding in pre- and postnatal service cytogenetics.

This report analyzes detection rates of chromosome aberrations as a function of stainig technique. Of 1,717 peripheral lymphocyte cultures processed by a midsize service cytogenetics laboratory, 23 chromosomal aberrations (1.3%) would not have been detected without the use of either R-banding or G-banding. These 23 cases comprise 21 of 64 non-Robertsonian structural autosomal changes and two of 68 gonosomal aberrations. In contrast, in 1,634 amniotic fluid cell cultures only one balanced rearrangement (0.06% of all cases) would not have been detected without banding. Combined with incidence rates from newborn cytogenetic screenings, these figures suggest that among 10,000 prenatal diagnoses for advanced maternal age, at most one chromosomally unbalanced fetus would be missed if banding were not routinely applied. Because of savings in time and possible automation, it is estimated that discretionary rather than routine use of chromosome banding in prenatal cytogenetics would allow for detection of at least twice as many age-related aneuploidies. In view of sharply rising demand for prenatal cytogenetic services, a discretionary approach might therefore assure a more equitable distribution of limited cytogenetic resources.

Adult↗

Current therapy for acute leukemia in childhood.

As therapy for acute leukemia in childhood becomes increasingly effective, the management of the child with leukemia become increasingly complex. The nurse caring for the child and his family must have an understanding of the principles of antileukemia therapy and the potential side effects. She must be prepared to apply nursing interventions to prevent unnecessary complications and to manage unavoidable ones. In addition, she must provide consistent psychosocial support to the child and his family.

Antineoplastic Agents↗

Prenatal alcohol exposure and cognitive development in the preschool years.

The teratogenic effects of drinking during pregnancy on cognitive development were investigated in a cohort of disadvantaged mother-infant pairs. Three indices associated with maternal alcohol use were related to comprehensive cognitive measures obtained during five in-home assessments through age four years, ten months. Birth weight and a tally of craniofacial anomalies were also evaluated as early indicators of fetal alcohol damage. Multiple analyses relating the alcohol and cognitive measures provided no evidence of an adverse alcohol effect on cognitive development in the absence of Fetal Alcohol Syndrome. Assessments based on confidence intervals indicated that an average decrement of more than two points (IQ equivalent) on the five cognitive measures is unlikely for relatively heavy levels of maternal alcohol use or alcohol-related problems. Marginal relationships were observed between cognitive measures and the neonatal indicators, but depended heavily on the influence of a child exhibiting signs consistent with Fetal Alcohol Syndrome. This case therefore received special attention. The implications of the relationships involving the neonatal indicators were investigated using arguments based on path analysis.

Alcohol Drinking↗

Prenatal and preschool age lead exposure: relationship with size.

This report examines possible adverse effects on size and growth associated with subclinical prenatal and preschool age lead exposure in an urban cohort followed prospectively from birth through early childhood. Measurements of weight, stature (length), and head circumference were obtained at birth and during five subsequent in-home assessments. Prenatal lead exposure was assessed by cord (n = 185) and maternal (n = 162) blood lead levels at delivery. Preschool blood lead samples were obtained at ages six months (n = 151), two years (n = 165), three years (n = 165), and four years, ten months (n = 164). Multivariate longitudinal analyses incorporating adjustment for covariates revealed no statistically significant adverse effects of prenatal lead exposure on either neonatal size or on subsequent growth through age four years, ten months. Similarly, no statistically significant adverse effects were found between the preschool lead indices derived from blood collected at or after age two years and ensuing size measurements. We also found no evidence for an interaction between pre- and postnatal lead exposure. A marginal inverse association was exhibited between blood lead at six months and subsequent measures of head circumference. Limitations in the implications of this result in the context of many nonsignificant tests were discussed.

Body Constitution↗

Toxocara canis infection in preschool age children: risk factors and the cognitive development of preschool children.

Risk factors for Toxocara canis (T. canis) infection were evaluated in a prospective study of disadvantaged preschool children. In addition, the hypothesis that T. canis exposure is associated with lower intelligence was tested. Seropositivity was tested at 2 years, 3 years, and at 4 years 10 months (4-10). Intelligence was measured at age 4-10 by the Full Scale IQ of the Wechsler Preschool and Primary Scales of Intelligence (WPPSI). Pica and ownership of a dog were unrelated to seropositivity. Seropositive children had lower scores on the Mental Development Index (MDI) of the Bayley Scales of Infant Development at age 1 year (prior to likely exposure). They also had less favorable scores on a measure of the quality of childrearing. These findings suggest that, for disadvantaged children, lower initial intelligence and less advantageous child rearing are risk factors for T. canis exposure. Seropositive children also had higher blood lead levels, probably as a result of the common pathway of hand to mouth transmittal. Seropositivity at 3 years, at age 4-10, or, cumulatively, at any of the age 2, 3, or 4-10 assessments was associated with the WPPSI IQ after adjustment for sociodemographic factors. Exposure at age 4-10-years was significantly associated with reduced IQ scores (p = 0.030). However, when the age 1 year MDI score was controlled, the estimate became nonsignificant. We, thus, can neither confirm nor deny a relationship of T. canis and intelligence, but the importance of considering prior developmental status is emphasized.

Animals↗

Low-level lead exposure in the prenatal and early preschool periods: language development.

Inconsistent results continue to be reported from studies linking low-level lead exposure and child development. This inconsistency is seen for both prenatal exposure and exposure in the preschool years. The primary outcome measures in most reports are indices of cognitive development, including IQ. Verbal skills may be particularly vulnerable to toxic insult. The fact that 2 y of age is both a time of peak exposure and also a time of rapid language development suggests that this may be a critical period for such an effect. The later prenatal and early infancy period, at which time the nervous system is developing rapidly, may also be critical exposure period. We examined the relationship of maternal and cord blood lead (PbB) at birth and venous PbB at 6 mo, 2 y, and 3 y with language measures at 1, 2, and 3 y of age. The sample consisted of disadvantaged urban children. Multivariate analyses revealed no statistically significant relationship of either prenatal PbB or early preschool PbB with language measures after control of cofactors. Supplementary partial correlations revealed a marginal relationship of cord PbB and mean length of utterance (MLU), which describes a child's ability to form meaningful word combinations. Because this analysis was one of a large number of analyses with both positive and negative regression coefficients, the possibility that this was a chance effect was considered. If there is an effect of low-level lead exposure on language development, that effect is not robust.

Child, Preschool↗

Transmitral endoventricular repair of left ventricular pseudoaneurysm following mitral valve replacement.

Left ventricular (LV) pseudoaneurysm is a rare but serious complication of mitral valve replacement and is usually the consequence of atrioventricular separation. Although there may be a role for nonoperative treatment in the presence of a small false aneurysm and in the absence of paravalvular leak, the presence of a large false aneurysm usually mandates surgical intervention. This may be hazardous in patients with concomitant LV dysfunction. We report a case of a patient who presented with a large LV pseudoaneurysm following numerous attempts of mitral valve replacements for a variety of reasons, including endocarditis. Some of the technical details of aneurysm repair and aspects of myocardial protection are discussed. In our patient, avoidance of cardioplegic arrest may have contributed to the successful outcome.

Aged↗

An analysis of hospital productivity and product change.

We developed a model to measure the contribution of changes in length-of-stay, service intensity, and productivity to the unusually low rate of growth in hospital costs per discharge in recent years. From 1992 through 1996 declining length-of-stay explained 97 percent of the decrease in real costs per discharge. Much of the drop was probably caused by care shifted from inpatient to postacute settings. Although complete data for our model are unavailable beyond that point, we cite several "leading indicators" that suggest that length-of-stay declines have played a smaller role in the continued low cost growth of 1997 and 1998 and that productivity may have risen sharply.

Efficiency, Organizational↗