PubMed HealthSearch

Biomedical subjects

J C Carey

Publications and source records attributed to J C Carey.

At least 19 recordsLinked to original sources

New syndrome involving the visual, auditory, respiratory, gastrointestinal, and renal systems.

A previously undescribed fatal multisystem syndrome involving the eyes, ears, lungs, intestines, and kidneys occurred in sibs. They both presented during early childhood with cataracts, otitis media, intestinal malabsorption, chronic respiratory infection, and failure to thrive. Later, they developed recurrent pneumonia (one was shown to have immotile bronchial cilia) and progressive azotemia leading to end-stage renal disease (ESRD) by late childhood. Both died of overwhelming infection (sepsis, meningitis). An autosomal recessive mode of inheritance is proposed since the normal parents were distant cousins, and 4 other sibs were normal.

Child, Preschool

Health supervision and anticipatory guidance for children with genetic disorders (including specific recommendations for trisomy 21, trisomy 18, and neurofibromatosis I).

A new model for care of children with genetic disorders has emerged from the pediatric and genetic communities in the last decade. This strategy incorporates the basic principles of well-child care, including ongoing psychological support for families, health screening, and prevention, into health supervision visits for children with these conditions. The same types of guidelines that have been developed for well children can also be applied to the routine follow-up and screening of children with these special health care needs. A number of general issues are applicable in the discussion of health supervision guidelines: correct diagnosis, analysis of the natural history of the condition, critical review of screening modalities and interventions, ongoing psychological support, and genetic counseling. With these points in mind and after a thorough review of the natural history of a disorder, guidelines can be developed and often applied to the primary care setting. Down syndrome is an ideal condition to which one can apply such a model because most children are cared for by primary care pediatricians, and the natural history is relatively well studied. Discussion of health provision in Down syndrome brings out some of the controversies regarding routine screening and review of interventions. Discussion of the natural history and uncertainties evident in the care of infants with trisomy 18 exemplifies the important issue of ongoing psychological support. Review of the natural history of neurofibromatosis emphasizes all of the principles involved in providing this model as a framework for health supervision. One of the key identified but unresolved issues is the decision as to when a primary care pediatrician can orchestrate the care on his or her own versus referral to a multidisciplinary team of specialists. In some conditions such as Down syndrome, it seems obvious that the primary care pediatrician can manage most of the care with periodic and appropriate referral to the necessary specialists. On the other hand, children with cystic fibrosis, meningomyelocele, and craniofacial syndromes almost always need referral to the specialist team because of the rarity of the disorder and the complex number of specialists involved in management. A condition such as NF-1 falls somewhere in between. Most children can be cared for in their childhood years by the pediatrician with referral when a symptom or sign emerges, but others would argue that all children with NF-1 need to be seen by a multidisciplinary team.(ABSTRACT TRUNCATED AT 400 WORDS)

Child

Nosological considerations of the neurofibromatoses.

We are on the threshold of evaluating the NF1 and NF2 loci with respect to variant forms of the neurofibromatoses. Genetic mapping of NF1, gene cloning and characterization of its encoded product, neurofibromin, provides a framework for the evaluation of the variant forms of NF. This may also apply to NF2 variant forms in the near future. The mapping approach in evaluating variant forms of NF should begin with the rigorous clinical assessment of familial cases whereby the establishment of genetic linkage in families with overlap syndromes might determine if either NF1, NF2, or a separate locus is involved in the phenotype. Conditions mapping to the NF1 locus could then be screened for mutations in hopes of identifying the etiologies of the variant forms of NF. Mutation identification should provide a molecular-based classification scheme for the variant forms of NF, now tentatively divided into alternative and related forms. It is expected that the nosology of the neurofibromatoses will most certainly change as more is learned of the NF1 and NF2 loci.

Diagnosis, Differential

Craniofacial malformations and their syndromes. An overview for the speech and hearing practitioner.

Congenital malformations of the craniofacial region represent an important class of human developmental disorders. Abnormalities of speech and hearing frequently occur in this vast array of conditions. Knowledge of the diagnostic criteria, genetics, and natural history of these conditions is important for audiologists and speech-language pathologists because of their close involvement with the children and families in their care-providing role. Awareness of the important distinction between individuals with isolated defects vs. individuals who have their facial defect as part of a syndrome is important in diagnosis and management. Referral for genetic counseling is always indicated in families who have questions about these issues. The dysmorphologist, genetics professional, and speech-language pathologists are among those who play key roles in the care of persons with these disorders.

Craniofacial Dysostosis

Intrapulmonary neuroglial heterotopia.

Nonteratomatous intrapulmonary neuroglial heterotopia not associated with birth trauma or frank vascular embolization has been described rarely. This article briefly reviews the literature, and presents two additional cases of intrapulmonary neuroglial heterotopia. We found 14 cases in the literature. Twelve of these cases had central nervous system disruption, where neuroglial elements were in direct contact with amniotic fluid. Several hypotheses have been proposed, including fetal aspiration of detached neural fragments within amniotic fluid, neural crest migration defects, and vascular embolization with implantation. Of our two cases, one represents the first occurrence where central nervous system abnormalities were secondary to mechanical disruption, rather than to a primary neural tube defect. Our second case represents the youngest documented occurrence (17 weeks gestation) of intrapulmonary neuroglial heterotopia. Additionally, immunohistochemical studies were performed on these lesions, the results of which favor their neural origin. We present these findings and suggest they support the aspiration mechanism for neuroglial heterotopia in lung tissue.

Abnormalities, Multiple

Osteochondrodysplasia with rhizomelia, platyspondyly, callosal agenesis, thrombocytopenia, hydrocephalus, and hypertension.

A female infant born at term to phenotypically normal nonconsanguinous parents had hypertension, thrombocytopenia, hydrocephalus, callosal agenesis, and nonlethal rhizomelic osteochondrodysplasia. Her osteochondrodysplasia was characterized roentgenographically by shortening and metaphyseal broadening of long bones, without bowing, and by platyspondyly, with deficient ossification of dorsal and central portions of vertebral bodies. By light microscopy, the iliac crest growth plate showed expansion of the zone of chondrocyte hypertrophy and degeneration, with faulty columnar alignment, sparse vascular ingrowth, and irregular mineralization at the zone of chondroosseous transformation. These findings appear to define a novel osteochondrodysplasia, which in association with hypertension, thrombocytopenia, hydrocephalus, and callosal agenesis may constitute a new syndrome.

Agenesis of Corpus Callosum

Barrier contraceptive methods and preeclampsia.

Recent investigations have suggested that women who use barrier methods of contraception may be at increased risk for preeclampsia. We used data from two prospective pregnancy studies to examine the relationship between contraceptive use before conception and preeclampsia. The preeclampsia rates among women using barrier contraceptives were not significantly higher than the rates in women using nonbarrier contraceptives or the rates in women using no contraceptives in either study. The odds ratios for preeclampsia in barrier contraceptive users in the two studies were 0.89 (95% confidence interval [Cl], 0.71 to 1.12) and 0.85 (95% Cl, 0.49 to 1.45) compared with nonbarrier contraceptive users and 0.91 (95% Cl, 0.71 to 1.16) and 0.81 (95% Cl, 0.48 to 1.35) compared with women using no contraceptives. After adjusting for other risk factors, we found no association between preeclampsia and barrier contraceptive use. Additional studies are needed to resolve this issue; however, we would recommend that women not be advised to avoid barrier contraceptives unless more data linking their use to preeclampsia appear.

Adolescent

Osteochondrodysplasia in Fryns syndrome.

Various skeletal abnormalities have been identified in roentgenograms of persons with Fryns syndrome, but to our knowledge, no histopathologic description of bone or cartilage has been published. We describe disordered endochondral and intramembranous bone formation in a premature female infant with Fryns syndrome. This infant and a full sibling (ie, had same set of parents) with Fryns syndrome in addition exhibited delayed ossification of the basiocciput and of cervical vertebral bodies, also previously undescribed in Fryns syndrome. These findings expand the spectrum of Fryns syndrome to include osteochondrodysplasia.

Abnormalities, Multiple

Antepartum cultures for Ureaplasma urealyticum are not useful in predicting pregnancy outcome. The Vaginal Infections and Prematurity Study Group.

To test the hypothesis that genital colonization with Ureaplasma urealyticum would predict adverse pregnancy outcome, 4934 women from five medical centers were evaluated for vaginal colonization with U. urealyticum between 23 and 26 weeks' gestation and followed up to delivery. U. urealyticum colonization was associated with maternal age, parity, racial-ethnic group, martial status, income, education, smoking, number of sexual partners, and colonization with Trichomonas vaginalis, Mycoplasma hominis, and bacterial vaginosis. After adjustment for medical and sociodemographic factors in a multivariate analysis, there was no difference in the mean birth weight or proportion of low-birth-weight infants delivered by women who carried U. urealyticum and those who did not. U. urealyticum colonization at 23 to 26 weeks was not associated with preterm rupture of membranes, preterm labor, or preterm delivery. A positive vaginal culture for U. urealyticum in midgestation does not predict those women at risk for preterm labor, preterm delivery, preterm premature rupture of membranes, or delivery of a low-birth-weight infant.

Adolescent

A randomized placebo-controlled trial of erythromycin for the treatment of Ureaplasma urealyticum to prevent premature delivery. The Vaginal Infections and Prematurity Study Group.

Ureaplasma urealyticum has been associated with low birth weight and histologic chorioamnionitis and it is a frequent isolate from the chorioamnion of patients who are delivered prematurely. In prior clinical trials using antibiotics active against U. urealyticum, antibiotic treatment was associated with reduced prematurity and increased mean birth weight. In this multicenter, randomized, double-blind clinical trial, pregnant women with U. urealyticum were treated with 333 mg of erythromycin base or placebo three times daily, starting between 26 and 30 weeks' gestation and continuing through 35 completed weeks of pregnancy. Women with urinary tract infection or Neisseria gonorrhoeae infection were excluded from the trial, and women with Chlamydia trachomatis or group B streptococci were excluded from these analyses. Erythromycin did not eliminate U. urealyticum from the lower genital tract. There were no significant differences between erythromycin- and placebo-treated women in infant birth weight or gestational age at delivery, in frequency of premature rupture of membranes, or in neonatal outcome.

Adult

The NF1 translocation breakpoint region.

The genetic locus that harbors mutation(s) responsible for neurofibromatosis type 1 (NF1) is on chromosome 17, within band q11.2. We have mapped the human homologue of a murine gene (Evi-2) that is implicated in myeloid tumors, to a location between two NF1 translocation breakpoints on chromosome 17. Sequencing studies predict that EVI2 is a membrane protein that may complex with itself and/or other proteins within the membrane, perhaps to function as part of a cell-surface receptor. In the course of these studies we have also identified three other transcripts (classes of cDNAs) from the NF1 region. Two of them map between the NF1 translocation breakpoints; the remaining transcript maps just outside this region. The map location implicates these four genes as possible candidates for harboring NF1 mutations.

Chromosome Aberrations

Deletions and a translocation interrupt a cloned gene at the neurofibromatosis type 1 locus.

Three new neurofibromatosis type 1 (NF1) mutations have been detected and characterized. Pulsed-field gel and Southern blot analyses reveal the mutations to be deletions of 190, 40, and 11 kb of DNA. The 11 kb deletion does not contain any of the previously characterized genes that lie between two NF1 translocation breakpoints, but it does include a portion of a rodent/human conserved DNA sequence previously shown to span one of the translocation breakpoints. By screening cDNA libraries with the conserved sequence, we identified a number of cDNA clones from the translocation breakpoint region (TBR), one of which hybridizes to an approximately 11 kb mRNA. The TBR gene crosses at least one of the chromosome 17 translocation breakpoints found in NF1 patients. Furthermore, the newly characterized NF1 deletions remove internal exons of the TBR gene. Although these mutations might act by compromising regulatory elements affecting some other gene, these findings strongly suggest that the TBR gene is the NF1 gene.

Adult

Congenital hypoplastic (Diamond-Blackfan) anemia in seven members of one kindred.

Congenital hypoplastic (Diamond-Blackfan) anemia is a rare macrocytic anemia, generally presenting during infancy or childhood. The condition usually occurs sporadically or in a pattern consistent with autosomal recessive inheritance, although autosomal dominant transmission has been proposed in some kindreds. We report the largest known kindred of congenital hypoplastic anemia, with at least 7 affected individuals over 3 generations, and propose that studies of this kindred may be useful for identifying the mechanism by which their genetic abnormality results in congenital hypoplastic anemia. Erythropoietic investigations on relatives show no inhibitors of erythropoiesis in serum, T-lymphocytes, or macrophages. Their erythroid progenitor cells (CFU-E and BFU-E) were generally quantitatively normal, and were capable of rapid proliferation, as judged by cell-cycle shortening. However, their erythroid progenitors displayed a relative insensitivity to recombinant erythropoietin, and produced relatively few normoblasts per erythroid progenitor cell. We propose that these and subsequent studies may be helpful in selecting candidate genes responsible for the molecular defect in this kindred.

Adolescent

Rubinstein-Taybi syndrome: a natural history study.

In order to examine several aspects related to the natural history of the Rubinstein-Taybi syndrome, we performed a questionnaire study of 50 patients who had been diagnosed with the condition. The cases were ascertained through a national parent support group and all of the individuals had been reared at home. The most frequent problems encountered were inadequate weight gain in infancy, eye problems, dental abnormalities, congenital heart defects, urinary tract problems, and severe constipation. These medical disorders and others resulted in approximately 10 times the average number of hospitalizations and surgeries as the general population of children. None of the 91 sibs of our study group were affected with the condition. Thirty-seven patients had undergone psychological testing with an average IQ of 51 and a range of 30 to 79. Timing for the attainment of various developmental stages was also determined. Individuals with Rubinstein-Taybi syndrome were found to have particular difficulty with expressive speech skills. Indexes for maladaptive behavior were calculated showing that approximately 10% of patients had significant behavior problems.

Abnormalities, Multiple

Three diagnostic signs in Williams syndrome.

In a series of 48 patients with Williams syndrome examined from 1984 to 1988, 3 physical manifestations were noted which have not been emphasized in previous reports of this condition. Unusual sacral creases were found in 25/48 patients, a linear array of hemangiomas (nevus flammeus) on the back in 3/48, and limitation of supination in 5/48.

Abnormalities, Multiple

Critical review of articles regarding pregnancy exposures in popular magazines.

To determine the scope of teratogen information available to the public through the media, a survey of 15 popular magazines was conducted. All 1985 issues of the selected magazines were reviewed for articles addressing pregnancy exposure concerns, yielding 56 articles from 10 magazines. The remaining 5 publications provided no pertinent articles. Two health professionals, both experienced teratology counselors, independently rated each article for accuracy of content and quality of presentation based on standardized evaluation criteria. The findings were compared and agreement for all criteria in each article was reached by the 2 reviewers. Regarding the quality of the information in the 56 articles, 31 (55.4%) were scored as misleading or inaccurate. On examination of overall presentation, 26 (46.4%) were rated as alarming and 8 (14.3%) presented a false sense of security; 22 (39.3%) provided a balanced presentation. A review of the types of articles rated revealed 19 (33.9%) general overviews of pregnancy issues, 18 (32.1%) news stories, 17 (30.4%) question-and-answer columns, and 2 (3.6%) feature stories. Of the reviewed papers, 7 (12.5%) included a citation from which the primary data could be obtained and only 14 of the articles (25%) suggested that the reader contact her/his healthcare provider regarding the issues. We conclude that the information available in popular magazines regarding exposures in pregnancy is frequently misleading, alarming, and unsupported by the scientific literature.

Evaluation Studies as Topic

The effect of physical activity during pregnancy on preterm delivery and birth weight.

The relationship between physical activity during pregnancy, preterm birth, and gestational age-adjusted birth weight was investigated prospectively in a cohort of 7101 women. This study is one of few to evaluate both employment- and non-employment-related physical activity. Prolonged periods of standing were associated with a modestly increased risk of preterm delivery (adjusted odds ratio for greater than or equal to 8 hours/day of standing = 1.31). Heavy work or exercise was not associated with preterm delivery (adjusted odds ratio for greater than or equal to 4 hours per day of heavy work = 1.04). The proportion of infants born preterm did not differ among women working in predominantly standing, active, and sedentary occupations. Physical activity was not associated with gestational age-adjusted birth weight after controlling for confounding variables. These data suggest that unmeasured socioeconomic differences among women reporting different levels of activity may account for previously described associations between physical activity and pregnancy outcome. Most pregnant women who report increased levels of physical activity are not at increased risk of preterm delivery or reduced intrauterine growth. However, these data do not address the role of activity restriction in the management of selected women at high risk for adverse pregnancy outcome.

Adolescent

Thoracic volume reduction as a mechanism for pulmonary hypoplasia in chondrodystrophic mice.

Day-18 fetal mice with chondrodysplasia (CHO) have been shown to have pulmonary hypoplasia and thoracic volume reduction, and it has been hypothesized that the former is a secondary effect of the latter. To establish a pathogenetic relationship between thoracic volume reduction and pulmonary hypoplasia, it must first be demonstrated that the decrease in thoracic volume precedes or coincides with the morphologic effect on the lungs. At 24-h intervals through gestation days 14 to 18, the thoracic volume and lung histopathology for normal and chondrodystrophic fetuses were estimated by image analysis of frontal histologic sections. Relative to normal littermates, the average thoracic volumes of day-16, day-17, and day-18 mutants were significantly decreased by 18%, 34%, and 49%, respectively. In the mutants' lungs the histology was normal through day 16, but on days 17 and 18 the frequency of the more distended primary saccules and the amount of potential airspace were decreased relative to normal. These results support the hypothesis that the relative decrease in thoracic volume of the mutant precedes the departure from normal for primary saccule development. The reduction effect on thoracic volume therefore is pathogenetically related to the hypoplastic lungs of fetal mice with lethal chondrodystrophy.

Animals