Search PubMed⌕ Search

Biomedical subjects

C A Moore

Publications and source records attributed to C A Moore.

At least 73 records · Page 4Linked to original sources

Increased risk for transverse digital deficiency after chorionic villus sampling: results of the United States Multistate Case-Control Study, 1988-1992.

Although numerous infants have been reported with transverse limb deficiencies after their mothers had undergone chorionic villus sampling (CVS), it has been unclear whether the procedure caused these defects. We report the results of the first multistate case-control study to assess and quantify the risk for specific limb deficiencies associated with CVS. Case subjects were 131 infants with nonsyndromic limb deficiency ascertained from 7 population-based birth defect surveillance programs, and born from 1988-1992 to mothers 34 years of age or older. Control subjects were 131 infants with other birth defects. We ascertained exposure to CVS from medical records and maternal and physician questionnaires. We assessed rates and timing of exposure to CVS, and estimated relative and absolute risks for anatomic subtypes of limb deficiency. The odds ratio for all types of limb deficiency after CVS from 8-12 weeks' gestation was 1.7 (95% confidence interval, 0.4-6.3). For specific anatomic subtypes, the strongest association was for transverse digital deficiency (odds ratio = 6.4; 95% confidence interval, 1.1-38.6). The risk for transverse digital deficiency increased with earlier gestational exposure (P < 0.01 for trend). We estimated that the absolute risk for transverse digital deficiency in infants after CVS was 1 per 2,900 births (0.03%). Exposure to CVS was associated with a sixfold increase in risk for transverse digital deficiency. The causality of this association is supported by its strength, specificity, biologic plausibility, and consistency with the results of previous studies. Although some centers already inform patients about risk for limb deficiency, this study quantifies the magnitude of risk associated with CVS from 8-12 weeks' gestation.

Case-Control Studies↗

Isolation and characterization of a cDNA encoding for preprosomatostatin containing [Tyr7, Gly10]-somatostatin-14 from the endocrine pancreas of rainbow trout, Oncorhynchus mykiss.

Somatostatins are a diverse group of peptides known to influence various aspects of growth and metabolism of vertebrates. In order to further our understanding of the physiological roles of somatostatins in fish, we initiated an analysis of somatostatin gene structure and expression in rainbow trout pancreas. Using rapid amplification of cDNA ends polymerase chain reaction, we have isolated, cloned, and sequenced a novel cDNA derived from pancreatic total RNA. Sequence analysis revealed a 624-bp cDNA containing the complete 5'-untranslated region with a single initiation site 107 bases from the most 5' end and a single putative polyadenylation site 13 bases from the most 3' end that was terminated with a polyadenylated tail. The deduced protein is a 115-amino-acid preprosomatostatin molecule with [Tyr7,Gly10]-somatostatin-14 at the C-terminus of the coding region, making the rainbow trout precursor a member of the preprosomatostatin II family. Based on the location of putative cleavage sites, we propose that rainbow trout pancreatic preprosomastatin II is processed to yield a 28-amino-acid and/or, possibly, a 14-amino-acid somatostatin II molecule. The results also suggest that there has been limited conservation of the preprosomatostatin II gene family among teleosts.

Amino Acid Sequence↗

Intrapair differences in personality and cognitive ability among young monozygotic twins distinguished by chorion type.

We evaluated placentation effects on behavioral resemblance of 44 pairs of monozygotic (MZ) twin children. Tested at ages 4-6, the twins' zygosity and placental type had been determined at their delivery. The sample included 23 monochorionic (MC) and 21 dichorionic (DC) MZ twin pairs: DC-MZ twins result from separation of blastomeres within 72 h of ovulation; MC-MZ twins arise from later duplication of the inner cell mass. Twins were individually administered the McCarthy Scales of Cognitive Ability, while their mothers separately rated each cotwin on an individualized 280-item form of the Personality Inventory for Children (PIC). Absolute differences between MC-MZ cotwins were smaller than those between DC-MZ cotwins for all 20 PIC scales, significantly so for 3 of 4 factor scales, 8 of 12 clinical scales, and 2 of 4 validity/screening scales from the PIC; in contrast, no consistent differences in intrapair resemblance of mono- and dichorionic MZ twins were found for the McCarthy Scales. The chorion differences found in the PIC data cannot be due to genetic differences, because all pairs are monozygotes; nor are they associated with differences in parity, gestational age, birth weight, maternal education, palmar dermatoglyphic asymmetry, or maternal knowledge of chorion type. We interpret our findings as suggestive evidence that variation in timing of embryological division, with effects on MZ twins' placental vasculature, has significant consequences for some dimensions of their behavioral development, as well.

Child↗

Paternal serum dioxin and reproductive outcomes among veterans of Operation Ranch Hand.

We studied whether paternal exposure to Agent Orange and its dioxin contaminant (2,3,7,8-tetrachlorodibenzo-p-dioxin) during the Vietnam War is related to adverse reproductive outcomes after service in Southeast Asia. The index cohort comprises conceptions and children of veterans of Operation Ranch Hand, the unit responsible for aerial spraying of herbicides in Vietnam from 1962 to 1971. The comparison cohort comprises conceptions and children of Air Force veterans who served in Southeast Asia during the same period but who were not involved with spraying herbicides. We found no meaningful elevation in risk for spontaneous abortion or stillbirth. In analyses of birth defects, we found elevations in risk in some organ system categories, which, after review of the clinical descriptions, were found to be not biologically meaningful. There was an increase in nervous system defects in Ranch Hand children with increased paternal dioxin, but it was based on sparse data. We found no indication of increased birth defect severity, delays in development, or hyperkinetic syndrome with paternal dioxin. These data provide little or no support for the theory that paternal exposure to Agent Orange and its dioxin contaminant is associated with adverse reproductive outcomes.

2,4,5-Trichlorophenoxyacetic Acid↗

Postmortem blood ferritin concentrations in sudden infant death syndrome.

AIMS--To confirm the observation of extremely high concentrations of ferritin in postmortem serum samples in sudden infant death syndrome (SIDS); to examine the factors influencing blood ferritin concentrations postmortem; to determine whether or not these high blood ferritin concentrations are characteristic of SIDS. METHODS--Postmortem samples of cardiac blood were obtained from 58 full term infants who died of SIDS and 14 full-term infants who died of a variety of other causes. Whole blood and serum ferritin concentrations were determined and compared with age at death, liver iron concentration, serum iron concentration, and serum lactate dehydrogenase activity. RESULTS--The median postmortem blood ferritin concentration for all infants was 18,600 micrograms/l, which is about 200 times the concentration found in the serum of normal, live infants. Serum iron concentrations were high and there was a highly significant correlation between serum ferritin and iron concentrations suggesting that much of the serum iron was contributed by ferritin. There was no significant difference between serum and whole blood ferritin concentrations. H to L type ferritin ratios were higher in blood from the left than the right ventricle of the heart but the ferritin was always predominantly L type. Blood ferritin concentrations rose rapidly after death but in samples collected at postmortem examination there was a significant correlation with liver iron concentration and an inverse correlation with age. Median values for blood ferritin were higher in SIDS (22,500; n = 58) than in control cases (6900; n = 7) dying under one year of age; however, in both groups ferritin concentrations decreased with age. CONCLUSIONS--Release of ferritin into the blood postmortem seems to be characteristic of infants dying before the age of one year rather than characteristic of SIDS. Two factors may cause such ferritin release postmortem: tissue breakdown and the high level of storage iron in cells of the reticuloendothelial system (including endothelial cells lining vessel walls). SIDS occurs when tissue iron concentrations are higher than at any other time of life. It is possible that the ready availability of iron enhances free radical damage which might be implicated in SIDS.

Age Factors↗

Effectiveness of bran supplement on the bowel management of elderly rehabilitation patients.

1. Constipation is a common problem in the elderly that affects up to 20% of those 65 years and older. 2. Patients receiving the fiber supplement had a significantly lower number of bowel agents per day as compared to the control patients. 3. Side effects from the additional fiber occurred in a subgroup of patients; thus, institution of additional fiber to the diets of ill, physically dependent patients is best done gradually and with close monitoring.

Aged↗

Impact of prenatal diagnosis on the birth prevalence of neural tube defects, Atlanta, 1990-1991.

OBJECTIVE: To determine the impact of prenatal diagnosis on the birth prevalence of neural tube defects (NTDs) in Atlanta during 1990 through 1991. METHODS: Live-born and stillborn infants with NTDs who were at least 20 weeks' gestation were ascertained by the Metropolitan Atlanta Congenital Defects Program (MACDP), a population-based birth defects registry. Prenatally diagnosed NTD-affected pregnancies were ascertained from the four perinatal centers and the three genetic laboratories operating in Atlanta during 1990 through 1991. Fetal death certificates were also reviewed for potential cases. RESULTS: During 1990 through 1991, MACDP ascertained 59 NTD cases, for a birth prevalence of 0.77/1000 live births. During this period, an additional 28 NTD-affected pregnancies were detected prenatally and terminated before 20 weeks' gestation. The adjusted NTD rate during 1990 through 1991, which includes prenatally diagnosed cases, was 1.13/1000 live births. CONCLUSIONS: Prenatal diagnosis is making a substantial impact on the birth prevalence of NTDs in Atlanta. However, since NTD rates in Atlanta were 2 to 2.5 per 1000 live births in 1970, prenatal diagnosis and termination of pregnancy does not completely account for the declining rate of NTDs.

Abortion, Induced↗

Issues in computerized polysomnography.

Reliable, properly tested, computerized systems for recording and scoring polysomnographic data would be welcome assistants in sleep laboratories. They potentially could save time, effort, paper, storage and cost. There exists, however, questions of competence and confidence. The nature and scope of published literature fails to convince many cautious sleep specialists that the cost-benefit ratio is favorable. Nonetheless, computerized systems for polysomnography are here to stay and are improving. Most of us represent past, present or future consumers of these products. The market will adjust to our level of knowledge and demands. We can adopt a variety of perspectives; however, the three basic modes of use should guide our thinking. For clarity, it is helpful to dissect 1) recording issues, 2) scoring issues and 3) monitoring issues from one another. Also, we should insist on greater statistical sophistication in testing trials. Manufacturers face a dilemma. Sleep disorders medicine has few true standards and many idiosyncratic practices. The expertise of consultants vary and manufacturers may be in no position to judge their collaborators. We desperately need guidelines to meet both manufacturers' and clinicians' expectations for testing and using computerized polysomnography.

Humans↗

Liver iron concentrations in sudden infant death syndrome.

To determine the biological significance of high concentrations of non-haem iron in the livers of infants dying from sudden infant death syndrome (SIDS), liver samples were obtained at necropsy from 66 infants who died from SIDS and 28 control infants who died before 2.5 years of age. All were full term deliveries. Liver iron concentrations decreased rapidly with age in the two groups. Liver iron concentrations in the SIDS infants and controls were compared for those infants who died between 1 month and 1 year of age. The median liver iron concentration in the SIDS infants was 296 micrograms/g wet weight; significantly higher than the median of 105 micrograms/g in controls. There was an inverse relation between iron concentration and age in the two groups, but an analysis of covariance confirmed the significantly lower values in controls. The frequency (22%) of HLA-A3 in SIDS infants was similar to that expected for the United Kingdom population (25%) and does not implicate the gene for haemochromatosis as a cause of high liver iron concentrations. These findings show that the peak incidence of SIDS occurs when mean concentrations of iron in liver tissue are higher than at any other time of life. Although a primary causal connection seems unlikely, high tissue iron concentrations may lower resistance to infection and enhance free radical formation, leading to tissue damage.

Age Factors↗

Asymmetric and symmetric long bone bowing in two sibs: an apparently new bone dysplasia.

We describe 2 sibs, one with congenital asymmetric long bone bowing and one with congenital symmetric long bone bowing. Other bony abnormalities in these sibs include beaten metal appearance of the skull, dolichomacrocephaly, ocular hypertelorism, and anterior beaking and bone-within-bone appearance of vertebrae. A differential diagnosis including campomelic dysplasia, kyphomelic dysplasia, hypophosphatasia, Grant syndrome, and osteogenesis imperfecta, and a discussion of potential mechanisms of long bone bowing are presented. The condition that these sibs have shares some characteristics of the above bone disorders, but appears to be a separate entity which to our knowledge has not been described previously.

Arm↗

Descriptive epidemiology of small intestinal atresia, Atlanta, Georgia.

To describe the epidemiology of small intestinal atresia (SIA) in Atlanta, Georgia, from 1968 through 1989, we used the Metropolitan Atlanta Congenital Defects Program, an active, population-based surveillance system for birth defects diagnosed during the first year of life. We identified 176 infants with SIA, a prevalence of 2.8 per 10,000 livebirths. Among black infants, the prevalence was 3.7 per 10,000 livebirths, significantly higher than the prevalence of 2.4 per 10,000 among white infants [relative risk (RR) = 1.6, 95% confidence interval (CI) = 1.1,2.1]. Nine infants were each one member of a unique pair of twins. The prevalence among twin infants was 7.3 per 10,000, significantly higher than the prevalence of 2.8 per 10,000 among singletons (RR = 2.7, 95% CI = 1.4,5.2). Forty-nine percent of the infants had duodenal atresia, 36% had jejunal atresia, and 14% had ileal atresia. Two infants (1%) had atresia at an unspecified site in the small intestine. We grouped the infants by anatomic location of SIA into four categories: isolated SIA (53%), SIA with multiple unrelated defects (21%), sequences (16%), and syndromes (10%). We then compared the isolated and multiple unrelated defects groups by gender, race, maternal age, birth weight and one-year mortality for each location of SIA. Among black infants the prevalence of isolated jejunal atresia was 1.4 per 10,000, significantly higher than the prevalence of 0.2 per 10,000 among white infants (RR = 6.3, 95% CI = 2.9, 13.5). The increased prevalence of these defects among twins was a particularly interesting finding.

Adolescent↗

Symmetry of mandibular muscle activity as an index of coordinative strategy.

Electromyographic activity of bilateral mandibular muscle pairs in humans was studied during several tasks: mastication, voluntary oscillation of the jaw, and speech production, as a replication and extension of an earlier investigation by Moore, Smith, and Ringel (1988). The synchrony of activity within and across these paired muscles (masseter, medial pterygoid, and the anterior belly of the digastric) was evaluated by statistical comparison of zero-lag cross-correlation coefficients between all possible pairs. Paired comparisons were classified and combined according to anatomical and biomechanical properties into comparisons of homologous pairs (e.g., synchrony of activity in right masseter with left masseter), ipsilateral synergists (e.g., right masseter with right medial pterygoid), contralateral synergists (e.g., right masseter with left medial pterygoid), ipsilateral antagonists (e.g., right masseter with right digastric), and contralateral antagonists (e.g., right masseter with left digastric). Statistical comparison of the coactivation within muscle groups (across tasks) and across these muscle groups (within tasks) revealed significantly different groups of coactivated groups for each of the three tasks studied. The grouping of these muscles into coactivated groups always included homologous pairs among those most synchronously active. During mastication, homologous pairs and ipsilateral synergists were coactivated to a degree significantly greater than either of the antagonistic groups or the contralateral synergists. During voluntary oscillation of the jaw, coactive muscle groups were shown to be primarily the homologous pairs; synergists were coactivated to a significantly lesser degree, and antagonistic muscles were reciprocally active. During speech production, only homologous pairs emerged as a highly coactive group, although synergists and antagonistic pairs were coactive to a lesser degree. This finding was interpreted as a further indication of the coordinative plasticity among mandibular muscles, and as a demonstration of the vast differences in the apparent coordinative strategies for speech and nonspeech tasks. Speculation regarding the root of these differences is focused on the differences in kinematic and force-generating requirements of each task.

Adult↗

Familial occurrence of renal and Müllerian duct hypoplasia, craniofacial anomalies, severe growth and developmental delay.

Absence of the kidneys and of the Müllerian structures has been reported in many patients. We report on a brother and sister, born to nonconsanguineous parents, with renal hypoplasia, Müllerian duct hypoplasia, and strikingly similar facial abnormalities. Both sibs have severe growth and developmental retardation. We think that the unique clinical findings in these sibs represent a new syndrome. The embryological and genetic implications of this condition are discussed.

Abnormalities, Multiple↗

Emergent applications of cardiopulmonary support: a multiinstitutional experience.

The use of emergent portable bypass systems is increasing. Because of limited patient use in any one institution, a combined experience can better determine the applicability of these systems. A total of 187 patients from 17 centers were analyzed. Causes leading to bypass initiation were cardiac arrest (125 patients), cardiogenic shock (44), profound hypothermia (7), pulmonary insufficiency (9), and miscellaneous (2). Weaning from bypass was successful in 30.5% (57 patients). Sixty-four patients (34.2%) were transferred to standard bypass or other modes of circulatory assist. Of the total population, 40 patients (21.4%) were alive greater than 30 days. There were no survivors of unwitnessed arrests. Major diagnostic or therapeutic interventions were carried out on bypass in 74.9% of all patients. In survivors, 77.1% (37/48) had major therapeutic interventions as compared with 50.0% (67/135) of nonsurvivors. Emergency portable bypass systems can successfully resuscitate and support cardiac hemodynamics, although the underlying causes necessitating bypass remain difficult to correct. When corrective intervention can be performed, there is an increased chance of survival. Unwitnessed arrest, prolonged cardiopulmonary resuscitation, and lack of treatment options are relative contraindications. Appropriate patient selection and early application of these systems should lead to improved survival.

Adolescent↗