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Biomedical subjects

W A Miller

Publications and source records attributed to W A Miller.

At least 73 records · Page 4Linked to original sources

A satellite RNA of barley yellow dwarf virus contains a novel hammerhead structure in the self-cleavage domain.

An RNA molecule with properties of a satellite RNA was found in an isolate of barley yellow dwarf virus (BYDV), RPV serotype. It is 322 nucleotide long, single-stranded, and does not hybridize to the viral genome. Dimers of the RNA, which presumably represent replicative intermediates, were able to self-cleave into monomers. In vitro transcripts from cDNA clones were capable of self-cleavage in both the plus (encapsidated) and minus orientations. The sequence flanking the minus strand cleavage site contained a consensus "hammerhead" structure, similar to those found in other self-cleaving satellite RNAs. Although related to the hammerhead structure, sequences flanking the plus strand termini showed differences from the consensus and may be folded into a different structure containing a pseudo-knot.

Base Sequence↗

Nucleotide sequences of the coat protein genes of two aphid-transmissible strains of soybean mosaic virus.

The nucleotide sequences of the coat protein genes and 3' non-coding regions of two aphid-transmissible isolates (G2 and G7) of soybean mosaic virus (SMV) were determined. The coat protein of the G2 isolate differs from that of the aphid non-transmissible N isolate by a single amino acid at position 12 (aspartic acid in N, glycine in G2 and G7). The G7 isolate differs from G2 and N at three and four amino acid residues, respectively. The nucleotide sequence similarity of the three isolates in the coat protein coding and 3' non-coding regions ranges from 93 to 100%, respectively. In contrast, watermelon mosaic virus 2 (WMV 2) is only 77% to 79% similar to the SMV isolates, suggesting that WMV 2 is a distinct virus and not an isolate of SMV as proposed previously.

Amino Acid Sequence↗

Genetic engineering of plants for virus resistance.

Historically, control of plant virus disease has involved numerous strategies which have often been combined to provide effective durable resistance in the field. In recent years, the dramatic advances obtained in plant molecular virology have enhanced our understanding of viral genome organizations and gene functions. Moreover, genetic engineering of plants for virus resistance has recently provided promising additional strategies for control of virus disease. At present, the most promising of these has been the expression of coat-protein coding sequences in plants transformed with a coat protein gene. Other potential methods include the expression of anti-sense viral transcripts in transgenic plants, the application of artificial anti-sense mediated gene regulation to viral systems, and the expression of viral satellite RNAs, RNAs with endoribonuclease activity, antiviral antibody genes, or human interferon genes in plants.

Base Sequence↗

AIDS knowledge and attitudes among adolescents in the rural southwest.

A survey of adolescents living in rural southwestern towns demonstrated their knowledge of the basic transmission routes of Acquired Immune Deficiency Syndrome (AIDS). Nevertheless, misconceptions and attitudes, which may interfere with adopting safe behaviors, persist. Significant differences in knowledge did exist between the ethnic groups surveyed. Further, American Indian and black adolescents were more likely to express attitudinal biases against people who have AIDS. We conclude that current media efforts have been successful in communicating basic information regarding transmission, but there may exist a need for ethnically specific programs that focus on the misconceptions and attitudes surrounding AIDS.

Acquired Immunodeficiency Syndrome↗

The efficacy of fetal sonographic biometry in Down syndrome screening.

Sonographic biometry has been proposed as a second-trimester Down syndrome screening modality. Approaches have relied on the apparent "shortened" femur length of fetuses with Down syndrome. Unfortunately, significant intercenter variation has been reported in the magnitude of this femur length reduction. In an effort to overcome many of these potential biases and better estimate the magnitude of femur length shortening in fetuses with Down syndrome, a retrospective review of femur length differences between 16 Down syndrome and 194 control fetuses was carried out. All scans were performed by one examiner who used the same equipment and measurement technique. A significant reduction in the observed to expected femur length ratio for a given biparietal diameter was identified in the Down versus control fetuses (0.9574 95% confidence interval 0.9197, 0.9952 versus 0.9999 95% confidence interval 0.9913, 1.0086) (p less than 0.008). However, the magnitude of this reduction was not sufficient to permit the use of this sonographic approach as an isolated marker for fetal Down syndrome.

Biometry↗

Sequence and organization of barley yellow dwarf virus genomic RNA.

The nucleotide sequence of the genomic RNA of barley yellow dwarf virus, PAV serotype was determined, except for the 5'-terminal base, and its genome organization deduced. The 5,677 nucleotide genome contains five large open reading frames (ORFs). The genes for the coat protein (1) and the putative viral RNA-dependent RNA polymerase were identified. The latter shows a striking degree of similarity to that of carnation mottle virus (CarMV). By comparison with corona- and retrovirus RNAs, it is proposed that a translational frameshift is involved in expression of the polymerase. An ORF encoding an Mr 49,797 protein (50K ORF) may be translated by in-frame readthrough of the coat protein stop codon. The coat protein, an overlapping 17K ORF, and a 3'6.7K ORF are likely to be expressed via subgenomic mRNAs.

Amino Acid Sequence↗

Sonographic detection of fetuses with trisomies 13 and 18: accuracy and limitations.

Nine fetuses having trisomy 13 and 15 fetuses with trisomy 18 were diagnosed by cytogenetic studies and also underwent a sonogram between 15 and 40 weeks. All nine fetuses with trisomy 13 had been prospectively identified as having sonographic findings suggestive of trisomy 13. Twelve of the 15 fetuses with trisomy 18 had sonographic abnormalities compatible with trisomy 18. Findings included abnormalities of the face and head, extremities, and diaphragmatic hernia. This report examines criteria for the ultrasound diagnosis of trisomies 13 and 18 and describes the accuracy of prenatal sonography for these diagnoses.

Chromosome Aberrations↗

Sequence and identification of the barley yellow dwarf virus coat protein gene.

The nucleotide sequence of the coat protein gene of barley yellow dwarf virus (BYDV, PAV serotype) was determined, and the amino acid sequence was deduced. The open reading frame, encoding a protein of relative molecular mass (Mr) 22,047, was confirmed as the coat protein gene by comparison with amino acid sequences of tryptic peptides derived from dissociated virions. In addition, a fragment of this gene expressed in Escherichia coli produced a product which was recognized by antibodies prepared against purified BYDV virions. An overlapping reading frame encoding an Mr 17,147 protein is contained completely within the coat protein gene.

Amino Acid Sequence↗

Effect of data collection method on results of serum digoxin concentration audit.

The appropriateness of serum digoxin concentration (SDC) orders was evaluated with respect to indication for use, sampling time, and action taken by physicians when the reported SDC was out of the normal therapeutic range; the effect of the two data-collection methods used (retrospective and concurrent audits) on the results was studied. Criteria for the appropriate use of SDCs were approved by the medical staff through the pharmacy and therapeutics committee. Patients on adult medicine services were entered into the study as daily SDC determinations were reported by the clinical laboratory. Most of the SDCs were evaluated using approved criteria by primary pharmacist clinicians who were concurrently monitoring drug therapy and participating with the treatment team. A retrospective audit of the same patients was conducted, using only chart review. A total of 134 SDCs involving 78 patients were evaluated. Concurrent-audit results indicated that 18.7% of the SDCs were ordered without an appropriate indication, 16.4% were sampled incorrectly with respect to proper timing, and 8.2% did not result in dosage adjustments when indicated. With respect to appropriate sampling time and overall use of SDCs, significantly more SDCs met the standards under concurrent audit than under retrospective audit. The retrospective chart review method of auditing may not detect as much pertinent information as is desirable.

Concurrent Review↗