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Biomedical subjects

L Arnold

Publications and source records attributed to L Arnold.

At least 19 recordsLinked to original sources
PubMed1992

First-year residents' performances compared with their medical school class ranks as determined by three ranking systems.

Difficulties encountered with deans' letters have prompted residency directors to rely on performance indicators, including class rank, that indicate the comparative positions of applicants. However, the validity of class rank as a predictor of performance in residency is not well established. The present investigation studied the relationship of class ranks to residents' performances, the systems of class ranking that correlated with residents' performances, and procedures that strengthened the relationship between ranking information and residents' performances. Three systems of class ranking are described. With each system, the authors used the same study group of 124 graduates (classes of 1986 and 1987) from a midwestern medical school with a baccalaureate-M.D. degree program; by 1991, each graduate had completed his or her first year of residency. All three systems were reliable for assignment of class rank. All three systems showed modest correlations with residents' performances. Multiple regression analysis revealed that a weighted combination of clinical performance measures bore the strongest relationship to performances in residency. Thus, the authors conclude that the formal computational ranking of students is not essential for the generation of reliable and valid deans' letters that can predict residents' performances. An in-depth evaluation that includes comparative information based on statistically generated formulas, as well as information based on personal qualities, may be a superior alternative.

Clinical Competence↗
PubMed1991

Multiple sets of adjacent mu E1 and oct-1 binding sites upstream of the pseudorabies virus immediate-early gene promoter.

Binding of cellular proteins to specific motifs in the promoter region of the immediate-early gene of pseudorabies virus was studied. The region was dissected into several portions that were used with HeLa cell nuclear proteins in mobility shift assays, DNase I footprinting, and a methylation interference assay. Close to the transcription start site (nucleotide + 1) are a TATA-box (-26 to -29), an Sp 1-binding motif (GGGGCGGGC) (-45 to -54), a CCAAT motif (-66 to -70), and, further upstream, an NF-microE1-binding site (AAGATGGC) (-161 to -168). Binding of a protein to the Sp1 site was demonstrated. Competition experiments show that the CCAAT motif might bind the NF-microE1 factor, rather than any of the known CCAAT-specific factors. Four domains were identified further upstream (nucleotides -200 to -500) from this promoter, each of which contained closely associated motifs where cellular transcription factors NF-microE1 and oct-1 could bind. These domains comprise what we call the upstream element. The orientation of the four NF-microE1 motifs in the upstream element is opposite to the orientation of the two NF-microE1 motifs located closer to the transcription start site. Transient expression of reporter genes was used to study the activity of the upstream element after transfection into 3T3 and HeLa cells. The upstream element was necessary for efficient expression of the pseudorabies virus immediate-early gene and increased somewhat the efficiency of the herpes simplex virus thymidine kinase promoter.

Base Sequence↗
PubMed1991

Caesium fluoride-induced changes in the c.d. spectra of synthetic DNA fragments.

Ten DNA fragments containing self-complementary alternating sequences of adenine and thymine differing in length and the starting nucleotide were studied by c.d. spectroscopy. It was found that d(TATATATA) but not d(ATATATAT), d(TATATA), d(CTATATAG) or (dT-dA)20 isomerized into the unusual X-DNA double helix at molar concentrations of CsF in solution. But in contrast to poly(dA-dT), the octamer (dT-dA)4, isomerized very slowly, at relatively low CsF concentrations and the isomerization was strongly dependent on the octamer concentration. A model is proposed to account for the observed properties of the B-to-X isomerization on the oligomer level.

Adenine Nucleotides↗
PubMed1991

Taxonomic classification of transitional follow-up care nursing interventions with low birthweight infants.

As new models of nursing care have merged, the need to understand the scope and content of nursing practice has increased. The domain of transitional follow-up nursing, an innovative model, was described by classification of nursing interventions according to the Taxonomy of Ambulatory Care Nursing. Content analysis of records of interventions employed by nurse specialists in the transitional follow-up care of very low birthweight infants yielded results that confirm the appropriateness of the Taxonomy of Ambulatory Care Nursing as a descriptor of transitional follow-up care.

Aftercare↗
PubMed1990

Ternary complexes of Escherichia coli aminoacyl-tRNAs with the elongation factor Tu and GTP: thermodynamic and structural studies.

The interaction of 18 different Escherichia coli aminoacyl-tRNA species with elongation factor Tu and GTP has been measured by a fluorescence titration assay under equilibrium conditions. The dissociation constants range from 1.9 +/- 0.2.10(-10) M up to 1020 +/- 250.10(-10) M depending on the nucleotide sequence, secondary structure and the chemical composition of the aminoacyl residue of the particular aminoacyl-tRNA. The 'aminoacyl domain' of tRNA consisting of the single stranded, four-nucleotide-long 3'-terminus, aminoacyl stem of seven base-pairs, T-stem and T-loop contains all elements necessary for binding EF-Tu.GTP. The efficiency of aminoacyl-tRNA interaction with EF-Tu.GTP is modulated by the sequence of this 'aminoacyl domain' and by natural modification of its nucleotide residues. An oligoribonucleotide resembling the aminoacyl stem of E.coli tRNA(Ala) and consisting of a four-membered 3'-end, a stem of seven base-pairs and a loop of six nucleotides was prepared by total chemical synthesis on a polymer support. It can be enzymatically aminoacylated by alanine but does not bind in its aminoacylated form to EF-Tu.GTP.

Anticodon↗
PubMed1990

[Experience with rapid molecular genetic diagnosis using the polymerase chain reaction].

The authors give an account of their experience with 1000 amplifications of DNA by the polymerase chain reaction for the prenatal diagnosis of cystic fibrosis. The method is demonstrated on examples of examinations of the informativity value and prenatal diagnosis in the first trimester of pregnancy in families with a 25% risk of cystic fibrosis, using J 3.11 (Msp I), met H (Msp I), KM 19 (Pst I), CS 7 (Hha I), Mp6d9 (Msp I), XV 2c (Taq I) probes. The authors summarize methodical check-up and safety measures to ensure the reliability of diagnoses made by the PCR method.

Cystic Fibrosis↗
PubMed1990

Effect of age on superoxide dismutase, catalase, glutathione reductase, inorganic peroxides, TBA-reactive material, GSH/GSSG, NADPH/NADP+ and NADH/NAD+ in Drosophila melanogaster.

The objective of this study was to investigate the possible role of oxygen free radicals in the aging process by studying the pattern of age-related changes in a broad spectrum of antioxidant defenses and indicators of oxidative stress in adult male Drosophila melanogaster. There were selective, but not universal, changes in the antioxidant defenses and indicators of oxidative stress. Activities of catalase and glutathione reductase and concentration of reduced glutathione decreased during the latter part of life. Superoxide dismutase activity tended to increase with age whereas glutathione peroxidase activity was undetectable. The ratios of reduced/oxidized glutathione and NADPH/NADP+, which are widely regarded as indicators of oxidative stress, decreased in the terminal phase of life. NADH/NAD+ ratio increased in the latter part of life. Concentration of inorganic peroxides increased during the first trimester of life and remained unchanged thereafter while that of thiobarbituric acid-reactants tended to decrease during aging. The main conclusion of this study is that age-related changes in antioxidant defenses and in levels of oxygen free radical reaction products are selective in nature and are quite variable in different species and tissues; however, the level of oxidative stress tends to increase during aging.

Aging↗
PubMed1990

The quarterly profile examination.

In sum, a school-wide examination such as the QPE can be used successfully. As a longitudinal, comprehensive testing system based on the objectives of the educational program, the QPE can satisfy internal and external requirements for assessment. Such an examination system could be an effective evaluation instrument for schools fostering problem-based and independent learning by students.

Education, Medical, Undergraduate↗
PubMed1990

An assessment of the student partnership program at the University of Missouri-Kansas City School of Medicine.

The partnership program at the University of Missouri-Kansas City (UMKC) School of Medicine pairs less experienced students with more experienced students to work together during the last four years of a six-year curriculum. The present study has explored how the partnership program is supposed to work, whether in reality it does work, what function it actually serves, and under what circumstances it operates best. In 1986 and 1987, the authors analyzed information from formal school documents, created and used questionnaires for the students and faculty, conducted semistructured interviews with selected students, and used the results of an annual survey, begun in 1978, of supervisors of first-year students who graduated from UMKC. The students and docents were found to favor the partnership system and reported that most partnerships worked well. The system's chief outcome is seen to be teaching teamwork: learning from and working together with student partners. The characteristics of the students, docents, and setting that contributed to successful partnerships are identified. The authors conclude that the partnership system at UMKC does achieve its objectives, which are described.

Attitude↗
PubMed1990

The rapid molecular genetic diagnosis of cystic fibrosis by polymerase chain reaction: an experience report.

The authors report their experience with about two thousand DNA amplifications by polymerase chain reaction (PCR) in prenatal diagnosis of cystic fibrosis. The method is demonstrated on examples of diagnostic informativity and prenatal diagnosis examination in a family at 1 in 4 risk of the disease using closely CF-linked diagnostic polymorphisms: J3.11/MspI, MetH/MspI, CS7/HhaI, KM19/PstI, Mp6-d9/MspI and XV2c/TaqI, PCR methodology and safety precautions are discussed.

Cystic Fibrosis↗
PubMed1990

Cystic fibrosis marker testing in Bohemia with polymerase chain reaction.

Conditions for assessing KM-19 probe detected by Pst-1 restriction fragment length polymorphism (RFLP) by means of polymerase chain reaction were provided. Computer controlled mechanical arm with waterbaths and cloned heat-stable DNA polymerase was used. Results of KM-19 allelic frequencies on 90 cystic fibrosis chromosomes are presented. Allele two frequency was -0.833.

Alleles↗
PubMed1990

[Sex determination using the polymerase chain reaction method for amplification of DNA segments on the X and Y chromosomes].

The authors tested the rapid and accurate prenatal and postnatal diagnosis of sex by the method of amplification of specific portions of DNA of sex chromosomes. To ensure a maximum reliability of the diagnosis the authors recommend combined examination of specific sequences from the heterochromatin region of the long arm of the Y chromosome (Yq) and from alphoid satellite sequences of DNA from the pericentromeric portion of chromosome X and Y (Xc and Yc). For further improvement of the reliability the authors recommend to digest the Yc amplification product obtained by means of restriction endonucleases Msp I, Eco Ri and Hini I. Correct assessment of the diagnosis was confirmed in all examined subjects (12) from DNA and chorium.

Female↗
PubMed1990

Transcutaneous bilirubinometer: intermeter reliability.

This study examined intermeter reliability on two transcutaneous bilirubinometers on 30 white prephototherapy infants between 36 and 42 weeks' gestation with birthweights greater than 2500 g. All infants were screened with both meters, on the forehead, within a 5-minute period. Meter readings were taken within 30 minutes following infant heelstick for serum bilirubin. The Pearson correlations between serum bilirubin and jaundice meter measurements were .75 for meter 1 and .76 for meter 2. The correlation between jaundice meter indices from the two meters was .87, leaving 13% of the variance in one meter not accounted for by the correlation with the other meter. An examination of the differences between the two meters revealed that in the upper range (greater than or equal to 16) meter 1 was always higher than meter 2 by, on the average, 2.6 points (SD = 1.3). In readings of 15 or less, the differences between the meters were inconsistent. Additionally, in 16 of 30 cases, the action levels from the two meters led to the same conclusion; in the remaining 14 cases, meter 1 gave a positive reading (indicating the need to determine serum bilirubin) while meter 2 gave an equivocal reading (indicating user discretion in deciding whether serum bilirubin should be determined). These data indicate that each meter should be individually evaluated to determine action indices, and that jaundice meters should not be used interchangeably on the same infant.

Bilirubin↗
PubMed1989

Transcription of the chicken myb proto-oncogene starts within a CpG island.

The nucleotide sequence of an 8.2-kb DNA fragment from the 5' proximal part of the chicken myb proto-oncogene spanning 1761 nucleotides upstream and 6436 nucleotides downstream from a presumed c-myb initiation codon was determined. A 3.3-kb G + C-rich region found in this sequence had also other features characterizing CpG islands, i.e. no CpG underrepresentation and lack of CpG methylation. In haematopoietic tissues c-myb mRNA synthesis starts in two major regions of the CpG island, namely 98 to 108 and 143 to 145 nucleotides upstream from the c-myb initiation codon. These two regions are in or close to the 124-bp evolutionarily conserved element located in the middle part of the CpG island. No alternative splicing of the 5' end of c-myb mRNA suggested earlier (1,2) was observed. The c-myb promoter contains neither TATA nor CAAT box-like structures at the usual positions. Instead, numerous potential Sp1 factor binding sites were found both upstream and downstream from the transcription initiation sites. Moreover, consensus v-myb protein DNA-binding sites were revealed in the promoter region and in sequences downstream from it.

Animals↗
PubMed1989

Nucleotide sequence of the right early region of Bacillus phage phi 15 and comparison with related phages: reorganization of gene 17 during evolution.

The rightmost 2016 bp of the Bacillus subtilis phage phi 15 genome were sequenced. The nucleotide sequence was compared with the homologous regions of the related phages PZA and phi 29. There are six open reading frames (ORFs) in this region of the phi 15 genome; all of them are present in the PZA and phi 29 genomes. One of the ORFs was assigned to gene 17, which is involved in the replication of the phage DNA. Gene 17 has undergone reorganization during the evolution of this phage family. Comparison of the nucleotide sequence of its mRNA-like strand in phi 15, PZA and phi 29 showed that deletions in its central and 3'-end-proximal parts are tolerated and do not interfere with the gene 17 product function. It seems that the only portion of gene 17 that has to be conserved to encode the functional product is its 5'-end-proximal part.

Amino Acid Sequence↗
PubMed1989

High school students' perceptions of nursing as a career: a pilot study.

A pilot survey of 300 high school junior students was implemented to elicit their perceptions of nursing and to explore the relationship between the experience of having a nursing role model and the decision to consider nursing as a career. The results indicated that the majority of students in the sample were aware of the caring and helping aspects of nursing, but there seemed to be a lack of knowledge about expanded roles and opportunities for advancement. High school students had significantly different mean opinion scores according to their sex (F = 17.03, p less than 0001) and the decision to consider nursing as a career (F = 10.00, p less than 002). There appeared to be a significant relationship between the experience of having a nurse role model and consideration of nursing as a career option (chi 2 = 8.23, p less than .0041). These findings have important implications for recruitment of young people into the nursing profession.

Adolescent↗
PubMed1989

Developing a program grant for use in model testing.

Early discharge is becoming a practice as well as a goal for the acute care institution. It is essential that nursing investigate the effects of this shift in the care delivery site from the acute care institution to the home and community. Brooten et al. describe a research model designed to do just that. Transitional care, as this team calls it, may soon become familiar jargon in community health care.

Clinical Nursing Research↗