PubMed Health⌕ Search

Biomedical subjects

J Wall

Publications and source records attributed to J Wall.

At least 19 recordsLinked to original sources
PubMed1992

Detection of multiple cystic fibrosis mutations by reverse dot blot hybridization: a technology for carrier screening.

We describe the implementation of a modified version of the reverse dot blot hybridization technology to detect eight cystic fibrosis mutations. The method is simple, quick, reliable, inexpensive, and nonradioactive and utilizes the sensitivity of the polymerase chain reaction coupled with colored or chemiluminescent substrates for mutation detection. We have used this system in a clinical laboratory to identify the delta F508, G542X, G551D, R553X, 621 + 1G----T, W1282X, N1303K, and 1717G----A mutations. The technique is practical for genotyping individuals at many potential mutation sites, as in cystic fibrosis and beta-thalassemia, in which over 95 mutations can cause disease. This technology appears to be the method of choice for the widespread carrier screening of multiple cystic fibrosis mutations.

Base Sequence↗
PubMed1988

Improved solid-phase extraction and liquid chromatography with electrochemical detection of urinary catecholamines and 5-S-L-cysteinyl-L-dopa.

We describe a rapid, precise, accurate liquid chromatographic procedure for determining urinary catecholamines and 5-S-L-cysteinyl-L-dopa. The catecholamines (norepinephrine, epinephrine, and dopamine) and 5-S-L-cysteinyl-L-dopa are extracted from 1.0 ml of urine together with internal standards, by using a Bond-Elut strong cation-exchange (SCX) and an affinity phenylboronic acid (PBA) extraction column in series. The eluate obtained from PBA column is then chromatographed on a reversed-phase C18 column with a mobile phase containing pentane- and heptanesulfonate as ion-pair reagents. The detection is achieved with an amperometric detector set at an oxidation potential of +0.55 V. The chromatography is complete is less than 8 min for catecholamines and less than 5 min for cysteinyldopa. The method can measure less than 2 micrograms/l for catecholamines and 5 micrograms/l for cysteinyldopa. Analytical recoveries of catecholamines and cysteinyldopa added to urine pool ranged from 90-107%. Between run coefficient of variation ranged from 4.7 to 8%. None of the drugs and catecholamines metabolites tested interfered with the assay.

Catecholamines↗
PubMed1986

Concentrations of endogenous free amino acids in rabbit reticulocyte lysates and the effect of incubation.

Amino acid analyses show that while the free amino acids found in the rabbit reticulocyte translation system do not increase during nuclease treatment or during prolonged storage, the endogenous levels of many amino acids are so high that the choice of a radioactive precursor for a translation should be based not only on the abundance of the amino acid in the translation product but also on its concentrations in the lysate preparation. It is shown that the variation of amino acid concentrations reported in this study to calculate the amount of radioactive amino acid necessary for satisfactory incorporation.

Amino Acids↗
PubMed1986

Dominantly inherited craniodiaphyseal dysplasia: a new craniotubular dysplasia.

We describe a mother and her male infant affected with a craniotubular dysplasia characterized by severe craniofacial hyperostosis and sclerosis with obliteration of paranasal sinuses and foramina of the skull base. Subsequent severe bilateral hearing loss and facial diplegia with relative sparing of the optic nerves were noted. The long bones show extreme asymmetric hyperostosis and sclerosis of the diaphyses and evidence of a modelling defect in the metaphyses. The spine, ribs, clavicles, and pelvis all show some degree of sclerosis and defective modelling, but are less severely involved. According to the definition by Gorlin, this disorder would best be classified as craniodiaphyseal dysplasia. Distinguishing features in these two patients as contrasted to previously described cases include a greater degree of hyperostosis and sclerosis than that described for other patients with craniodiaphyseal dysplasia, apparent dominant transmission, and significant metaphyseal involvement.

Adult↗
PubMed1986

RNs may cost less than you think.

The health care environment is in a new era. Hospital and nursing administrators will be faced with tough decisions regarding number and skill level of staff. Productivity of various levels of nursing personnel is one parameter upon which decisions can be made. In this research, productivity is defined as the percentage of time spent in direct care, indirect care, and unit-related activities. The research indicates that the higher the level of personnel, the higher the productivity.

Clinical Competence↗
PubMed1979

Cortical projections of the medial visual area in the owl monkey, Aotus trivirgatus.

The cortical projections of the Medial Area (M) of the owl monkey were studied using the autoradiographic method. Area M projects to several extrastriate areas, including Area 18, in a pattern of terminations unlike that which would be expected if M was part of a larger Area 19 or V III band. The pattern of terminal lamination was found to be somewhat unusual in that projections were to layers VI, I and the deep portion of layer V in the major target areas.

Animals↗
PubMed1974

Scanning transmission electron microscopy at high resolution.

We have shown that a scanning transmission electron microscope with a high brightness field emission source is capable of obtaining better than 3 A resolution using 30 to 40 keV electrons. Elastic dark field images of single atoms of uranium and mercury are shown which demonstrate this fact as determined by a modified Rayleigh criterion. Point-to-point micrograph resolution between 2.5 and 3.0 A is found in dark field images of micro-crystallites of uranium and thorium compounds. Furthermore, adequate contrast is available to observe single atoms as light as silver.

Crystallography↗