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R J Mier

Publications and source records attributed to R J Mier.

9 recordsLinked to original sources
PubMed2002

Testing for genetic associations with the PAX gene family in a spina bifida population.

Neural tube defects (NTDs) are among the most common severely disabling birth defects in the United States, affecting approximately 1-2 of every 1,000 live births. The etiology of NTDs is multifactorial, involving the combined action of both genetic and environmental factors. A nonparametric linkage method, the transmission disequilibrium test (TDT), was utilized to determine if the genes in the PAX family play a role in the formation of NTDs. DNA from 459 spina bifida (SB) patients and their parents (430 mothers and 239 fathers, for a total population of 1,128 subjects) was tested for linkage and association utilizing polymorphic markers from within or very close to the PAX genes of interest. Significant findings were obtained for the following markers: marker locus D20S101 flanking the PAX1 gene (P = 0.019), marker locus D1S228 within the PAX7 gene (P = 0.011), and marker locus D2S110 within the PAX8 gene (P = 0.013). Even though our findings are only mildly significant, given the known expression patterns of the PAX genes in development and the availability of their sequences, we elected to follow up these results by testing these genes directly for mutations utilizing single-strand conformational analysis (SSCA) and direct sequencing. Multiple variations were detected in each of the PAX genes with significant TDT results; however, these variations were not passed from parent to child in phase with the positively transmitted allele. Therefore, it is unlikely that these variations contribute to susceptibility for SB, but rather are previously unreported polymorphisms.

Adolescent↗
PubMed2002

Testing for genetic associations in a spina bifida population: analysis of the HOX gene family and human candidate gene regions implicated by mouse models of neural tube defects.

Neural tube defects (NTDs) are among the most common severely disabling birth defects in the United States, affecting approximately 1-2 of every 1,000 live births. The etiology of NTDs is multifactorial, involving the combined action of both genetic and environmental factors. HOX genes play a central role in establishing the initial body plan by providing positional information along the anterior-posterior body and limb axis and have been implicated in neural tube closure. There are many mouse models that exhibit both naturally occurring NTDs in various mouse strains as well as NTDs that have been created by "knocking out" various genes. A nonparametric linkage method, the transmission disequilibrium test (TDT), was utilized to test the HOX gene family and human equivalents of genes (when known) or the syntenic region in humans to those in mouse models which could play a role in the formation of NTDs. DNA from 459 spina bifida (SB) affected individuals and their parents was tested for linkage and association utilizing polymorphic markers from within or very close to the HOXA, HOXB, HOXC, and HOXD genes as well as from within the genes/gene regions of eight mouse models that exhibit NTDs. No significant findings were obtained for the tested markers.

Adolescent↗
PubMed2001

Osteoarthritis in children associated with a mutation in the type II procollagen gene (COL2A1).

A single-base mutation resulting in an arginine-519-cysteine (R519C) mutation of type II procollagen (COL2A1) has been shown to result in precocious osteoarthritis with mild spinal chondrodysplasia without severe foreshortening (OMIM 604864). The nature of childhood disease among affected individuals has not been described. The recent presentation of four children with this mutation allows us to provide clinical correlation. This form of premature osteoarthritis may present in childhood and should be considered in the differential diagnosis of childhood arthropathy presenting in the context of a positive family history.

Adolescent↗
PubMed2000

Treatment of sialorrhea with glycopyrrolate: A double-blind, dose-ranging study.

OBJECTIVE: To determine the safety and efficacy of glycopyrrolate in the treatment of developmentally disabled children with sialorrhea. DESIGN: Placebo-controlled, double-blind, crossover dose-ranging study. SETTING: Outpatient facilities in 2 pediatric hospitals. PATIENTS: Thirty-nine children with both developmental disabilities and excessive and bothersome sialorrhea. MAIN OUTCOME MEASURES: Parent and investigator evaluation of change in sialorrhea and adverse effects. RESULTS: Glycopyrrolate in doses of 0.10 mg/kg per dose is effective at controlling sialorrhea. Even at low doses, 20% of children may exhibit adverse effects severe enough to require discontinuation. CONCLUSIONS: Glycopyrrolate is effective in the control of excessive sialorrhea in children with developmental disabilities. Approximately 20% of children given glycopyrrolate may experience substantial adverse effects, enough to require discontinuation of medication. Arch Pediatr Adolesc Med. 2000;154:1214-1218.

Adolescent↗
PubMed1992

Severe insulin resistance and diabetes mellitus in mandibuloacral dysplasia.

Mandibuloacral dysplasia (MAD) is a syndrome with onset in midchildhood. The predominant characteristics of MAD include flexion contractures; mandibular hypoplasia; loss of body fat; atrophic, speckled skin; and progressive osteolysis of the clavicles. We studied three males with MAD. Each had lipodystrophy of the extremities, with sparing of the face and neck. All had moderate hyperlipidemia. In response to oral glucose, each had a diabetic response, with peak insulin levels between 2870 and 22,960 pmol/L. Insulin-stimulated glucose disposal was determined in two patients with MAD. At an insulin infusion rate of 120 mU/m2 per minute, glucose disposal was less than 25% of that measured at similar levels of insulinemia in nondiabetic control subjects, indicating marked insulin resistance in patients with MAD. The insulin resistance occurred without obesity, excessive levels of counterregulatory hormones, or anti-insulin-receptor antibodies. We suggest that MAD is a previously undescribed form of lipodystrophic insulin-resistant diabetes mellitus.

Abnormalities, Multiple↗
PubMed1988

Treatment of aniline poisoning with exchange transfusion.

A case of aniline poisoning with methemoglobinemia unresponsive to methylene blue is described. Exchange transfusion proved successful. A rationale for the failure of methylene blue under these circumstances is described.

Aniline Compounds↗
PubMed1987

Down's syndrome.

We discuss the ethical, psychosocial, economic, and medical dimensions of the treatment and management of a child with Down's syndrome and a congenital heart defect.

Down Syndrome↗
PubMedDate not supplied

The effect of osteotomy on bowing and height in children with X-linked hypophosphatemia.

The clinical records of 40 patients with X-linked hypophosphatemia who were treated and followed for at least 36 months were examined retrospectively. The patients were divided into those treated with medication only (group A) and those treated with medication and surgery (group B). At follow-up, significant improvement in bowing angles was noted for group B patients compared with those treated medically. There was, however, no improvement in the height of children in group A, and there was a significant decrease in height among the children treated surgically (group B). Neither height nor bowing angles of femurs or tibias at presentation predicted the need for future osteotomies. However, children who eventually needed surgery were found to be obese at presentation significantly more frequently than children who did not require osteotomy.

Adolescent↗