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Biomedical subjects

L K Miller

Publications and source records attributed to L K Miller.

At least 163 records · Page 9Linked to original sources
PubMed1987

Pelvic osteomyelitis complicating Crohn's disease: diagnosis by computed tomography.

An unusual case of pelvic osteomyelitis complicating granulomatous ileocolitis is herein reported. Computed tomography of the abdomen was crucial in detecting osteomyelitis of the right iliac wing as well as the associated fistulous tracts and abscesses adjacent to the involved bone. Clinical and radiographic features of this rare complication of Crohn's disease are presented, together with a brief review of the pertinent literature.

Abscess↗
PubMed1987

Prenatal care adequacy and the outcome of adolescent pregnancy: effects on weight gain, preterm delivery, and birth weight.

A prospective study of 757 adolescents who gave birth to singleton live-born infants was undertaken to assess effects of prenatal care on pregnancy outcome. The analysis indicated that the odds of low pregnancy weight gain for gestation was reduced by a factor of two (odds ratio = 0.50, P less than .05) for adolescents with adequate prenatal care; the risk of preterm delivery was reduced with both adequate (odds ratio = 0.34, P less than .01) and intermediate prenatal care (odds ratio = 0.46, P less than .05). Birth weight was increased by an average of 157 g with adequate care (P less than .05) and 107 g with intermediate care (P less than .05). After adjusting for pregnancy weight gain and preterm delivery, differences in birth weight were much smaller and no longer statistically significant, suggesting indirect effects of care on birth weight (ie, improvements in weight gain adequacy and in preterm delivery).

Adolescent↗
PubMed1986

Changes in the nucleoprotein complexes of a baculovirus DNA during infection.

The nature of the DNA-protein complexes assumed by Autographa californica nuclear polyhedrosis virus (AcNPV) DNA during infection of Spodoptera frugiperda cells was investigated by micrococcal nuclease digestion of infected nuclei. Both parental viral DNA and progeny viral DNA assumed a chromatin-like structure early in infection. By late times (24 hr) p.i., the viral DNA acquired a unique nucleoprotein structure. In addition to fragments of mononucleosome size (185 bp), two subnucleosomal bands of 120 and 90 bp were observed. The subnucleosomal bands contained exclusively viral DNA. No alteration in the nature of the host chromatin structure following AcNPV infection was observed. An examination of the basic chromatin-associated proteins revealed two major viral-induced proteins having molecular weights of 15K and 39K. The induction of the basic 15K protein between 10 and 24 hr p.i. coincided with the appearance of the altered nucleoprotein structure observed by 24 hr p.i. and the cessation of histone synthesis.

Animals↗
PubMed1986

Baculovirus transcription in the presence of inhibitors and in nonpermissive Drosophila cells.

Regulation of transcription within four well-defined regions of the DNA genome of the baculovirus Autographa californica nuclear polyhedrosis virus (AcNPV) was studied in a permissive lepidopteran cell line. Spodoptera frugiperda IPLB-SF-21 and a nonpermissive dipteran cell line, Drosophila melanogaster DL-1. Cycloheximide, an inhibitor of protein synthesis, was used to identify immediate early transcripts and aphidicolin, an effective inhibitor of DNA replication, was used to distinguish early and late transcripts in S. frugiperda cells. Immediate early transcripts were identified in the HindIII-K (85 to 87.5%), the HindIII-I/EcoRI-F (I/F from 35 to 37%) and the HindIII-P/EcoRI-P (p10 from 88.5 to 89.5%) regions of the genome. Late RNAs, defined by their sensitivity to aphidicolin as well as cycloheximide, overlapped the immediate early RNAs. Specific viral transcripts were synthesized in nonpermissive D. melanogaster cells infected with AcNPV but late viral transcripts were not observed.

Animals↗
PubMed1986

Variation in the temporal expression of overlapping baculovirus transcripts.

To investigate gene expression from the Autographa californica nuclear polyhydrolysis virus genome (AcNPV), complementary DNA (cDNA) was synthesized from polyadenylated RNA transcribed at 2 h and 10 h postinfection (p.i.) and then cloned into Escherichia coli using plasmid pUC-9. Eighteen 2 h cDNA plasmids were homologous to five distinct regions of the viral genome, while forty-nine 10 h cDNA plasmids were homologous to 15 regions including the five regions transcribed at 2 h. Temporal expression of polyadenylated RNA transcribed from diverse regions of the genome was examined using Northern blot hybridization with the above 2 and 10 h cDNA probes. All regions displayed overlapping sets of RNAs. In addition to HindIII-I/EcoRI-F (IF) and HindIII-B2/EcoRI-H (B2H), several, but not all, regions showed a sequential appearance of higher molecular weight RNAs as the infection progressed. Each overlapping set of RNAs exhibited unique characteristics including variations in the number of overlapping transcripts, their temporal regulation, and their relative abundance during the course of infection.

Animals↗
PubMed1986

Smoking and adolescent pregnancy outcome.

Birth weight, length of gestation, fetal/neonatal death, and admission to neonatal intensive care were examined for 265 adolescents who smoked during pregnancy and 510 nonsmokers. After adjusting for potential confounding variables, adolescent smokers had infants weighing 222 g less than nonsmokers. Smokers were also 3.1 times more likely to have a small-for-gestational-age infant compared to the nonsmokers. Smoking status had little effect on low birth weight (less than 2500 g), preterm delivery (less than 37 weeks gestation), fetal/neonatal death, or neonatal intensive care admission. Attributable risks suggested that small-for-gestational-age births to adolescents potentially could be reduced by up to 40% and adolescent low birth weight reduced by as much as 14.5% if smoking during pregnancy was stopped.

Adolescent↗
PubMed1986

Bidirectional transcription from a solo long terminal repeat of the retrotransposon TED: symmetrical RNA start sites.

A single copy of the retrotransposon TED was found integrated within the DNA genome of the insect baculovirus, Autographa californica nuclear polyhedrosis virus. After excision of the element from the viral genome, a single long terminal repeat (LTR) remained behind. We have examined the effect of this solo TED LTR on the local pattern of viral transcription. Most prominent was the transcription of two sets of abundant RNAs; both originated within the LTR but extended in opposite directions into flanking viral genes. By promoting symmetric transcription of adjacent genes, the solo LTR has the capacity to activate or repress gene expression in two directions. Primer extension analysis demonstrated that the divergent LTR transcripts were initiated near the same point within a 22-base-pair sequence having hyphenated twofold symmetry. Analogous symmetries at the initiation sites of other retrotransposon LTRs, including copia and Ty, suggested that these sequences serve to establish the precise start for transcription.

Animals↗
PubMed1985

Temporal regulation of baculovirus RNA: overlapping early and late transcripts.

Analysis of the temporal sequence of RNA transcription within the Autographa californica nuclear polyhedrosis virus genome revealed individual transcription units composed of overlapping early or late RNAs, or both. High-resolution S1 nuclease mapping within the 3.0-kilobase HindIII-K fragment located five overlapping RNAs (1.07, 1.38, 2.63, 3.16, and 3.50 kilobases) transcribed in the same direction and terminated at a common 3' site. The smallest RNAs appeared early but were replaced in time by successively larger RNAs initiated further upstream. Primer extension analysis supported the contention that this temporal regulation involved the sequential activation of upstream promoters and the coordinate deactivation of downstream promoters. As such, transcription from upstream genes may suppress that of downstream genes via transcriptional interference (promoter occlusion) and thereby facilitate sequential expression of different viral functions. In contrast, overlapping RNAs with extended 3' ends were transcribed from the abundantly expressed p10 and polyhedrin genes mapping to the HindIII-Q,P/EcoRI-P and HindIII-V/EcoRI-I fragments, respectively. These RNAs were synthesized maximally during the very late occlusion phase and consisted of a major small transcript and several larger but less abundant transcripts.

Gene Expression Regulation↗
PubMed1985

Baculovirus-mediated expression of bacterial genes in dipteran and mammalian cells.

A recombinant baculovirus containing the Escherichia coli chloramphenicol acetyltransferase (CAT) gene under the control of the Rous sarcoma virus long terminal repeat promoter and the E. coli beta-galactosidase gene under the control of the very late baculoviral polyhedrin promoter was used to determine if Autographa californica nuclear polyhedrosis virus, a baculovirus of Lepidoptera, can enter and express viral DNA in dipteran (Drosophila sp.) and mammalian (Mus sp.) cells that are considered refractory to baculovirus replication. Following infection, CAT gene expression was observed in both dipteran and mammalian cells, but expression in the mammalian cell line was less than 0.05% of that observed in either dipteran or lepidopteran cells. Although the level of CAT gene expression was similar in permissive lepidopteran and nonpermissive dipteran cells, expression of beta-galactosidase activity from the late polyhedrin promoter in dipteran or mammalian cells was less than 0.3% of the levels observed in lepidopteran cells. These results indicate that foreign gene expression in nonpermissive cells is promoter dependent and that late viral gene expression is restricted in these cells. The Rous sarcoma virus long terminal repeat allows substantial CAT gene expression in both a D. melanogaster cell line and Aedes aegypti midgut cells. Baculovirus DNA undergoes a limited number of replications in Drosophila cells. The results are relevant to baculovirus host range, the safety of baculoviruses as pesticides, and the development of baculovirus pesticides with expanded host ranges.

Acetyltransferases↗
PubMed1984

Treatment of penicillin-resistant Neisseria gonorrhoeae with oral norfloxacin.

Norfloxacin, an orally administered quinoline carboxylic acid that is structurally related to nalidixic acid, has been shown to be highly active in vitro against penicillinase-producing Neisseria gonorrhoeae. Ninety-two men with culture-proved gonococcal urethritis, 46 per cent with penicillinase-producing N. gonorrhoeae, and 27 per cent with non-penicillinase-producing N. gonorrhoeae that was resistant to penicillin were given either 1200 mg of norfloxacin divided into two equal oral doses four hours apart (59 patients) or 2 g of spectinomycin intramuscularly (33 patients). All patients in both treatment groups were cured. No adverse reactions were reported in either group. We conclude that a two-dose, single-day regimen of orally administered norfloxacin is effective therapy for uncomplicated urethritis caused by penicillin-resistant strains of N. gonorrhoeae.

Administration, Oral↗
PubMed1984

Sources of visual field interference in children and adults.

Subjects at three grade levels, third, sixth, and college (8, 11, and 20 years of age, respectively), were asked to identify briefly presented words accompanied by either words or letter strings in the same or opposite hemifield. Results indicated two sources of visual field interference, one relating to the presence of alphanumeric information elsewhere in the visual field and the second concerning the meaningfulness (lexical identity) of that information. The former showed a decrease in importance with age, and the latter an increase. Results were discussed in terms of the development of selective attention and hemispheric interaction.

Adult↗
PubMed1984

Strong and regulated expression of Escherichia coli beta-galactosidase in insect cells with a baculovirus vector.

The N-terminal region of the gene encoding polyhedrin, the major occlusion protein of the insect baculovirus Autographa californica nuclear polyhedrosis virus (AcNPV), has been fused to DNA encoding Escherichia coli beta-galactosidase. The fused gene was inserted into the AcNPV DNA genome by cotransfection of insect cells with recombinant plasmid DNA and wild-type AcNPV genomic DNA. Recombinant viruses were selected as blue plaques in the presence of a beta-galactosidase indicator, 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside. Studies of one such virus, L1GP-gal3, indicated that the synthesis of beta-galactosidase is temporally controlled beginning late (20 h) in infection after the release of infectious virus particles from the cell. By 48 h postinfection, a remarkably high level of expression is achieved. On the basis of these results, AcNPV should be a useful vector for the stable propagation and expression of passenger genes in a lepidopteran cell background. A generalized transplacement vector that facilitates the construction and selection of recombinant viruses carrying passenger genes under their own promoter control has also been developed.

Amino Acid Sequence↗
PubMed1983

Cardiopulmonary toxicity in patients with breast carcinoma during plasma perfusion over immobilized protein A. Pathophysiology of reaction and attenuating methods.

Tumoricidal reactions in dogs with spontaneous breast carcinoma occur after perfusion of plasma over protein A derived from Staphylococcus aureus and immobilized in collodion charcoal. When this treatment was extended to humans with breast cancer, hemodynamic and physiologic changes were noted. The evolution and spectrum of these reactions were evaluated during 47 plasma infusions in five patients. Initial treatment conditions consisting of rapid perfusion of plasma over high quantities of immobilized protein A were employed for 12 treatments in two patients. Within 30 minutes after treatments were begun, mean blood pressure, systemic vascular resistance, and stroke volume increased, as did heart rate, cardiac output, and rectal temperature; however, mean pulmonary artery pressure and total pulmonary resistance did not change. At 90 minutes, hypotension developed (lowest mean blood pressure was 59 +/- 14 mm Hg) that was associated with a decrease in systemic vascular resistance and total pulmonary resistance (536 +/- 66 and 146 +/- 44 dynes . second . cm-5, respectively). Cardiac output increased, tachycardia developed, stroke volume decreased, and rectal temperature increased. During the hypotensive phase, values of creatinine clearance and fractional excretion of sodium diminished. Noncardiogenic pulmonary edema appeared occasionally, with bronchospasm noted once. No hemodynamic changes were seen when saline solution was passaged over protein A immobilized in collodion charcoal or when autologous plasma was given without passage over protein A immobilized in collodion charcoal. Treatment conditions were modified by diminishing protein A quantity and plasma volume and slowing plasma perfusion rate, which resulted in significant attenuation of all cardiopulmonary responses. This report, then, defines for the first time the physiologic basis of the cardiopulmonary toxicity in humans after plasma perfusion over immobilized protein A.

Breast Neoplasms↗
PubMed1983

Hemifield independence in the left handed.

Tachistoscopically presented arrays containing either a single word or two words in different configurations were given to left- and right-handed subjects. Several measures indicated hemifield, and by implication, hemispheric independence for word recognition was more likely to be found among left- than right-handers. Differences within the left-handed group associated with the presence of family sinistrality and writing posture were also found. Results were discussed with respect to the view that bilateral representation of language frequently occurs in left-handed adults.

Adolescent↗
PubMed1983

Effectiveness of aztreonam, a new monobactam antibiotic, against penicillin-resistant gonococci.

Since the recognition of penicillinase-producing strains of N gonorrhoeae (PPNG) in 1976, these organisms have attained a worldwide distribution. The treatment of choice for infection due to PPNG has generally been spectinomycin administered im. In 1981, however, an infection from California was reported to be due to a strain of PPNG that was also resistant to spectinomycin (MIC, greater than 2,048 micrograms/ml) [1]. Throughout 1982, seven such isolates were reported worldwide [2], and in January 1983 an epidemiologically linked series of 27 cases of infection due to spectinomycin-resistant PPNG occurred in Korea. Because of the apparent declining utility of spectinomycin, we studied the efficacy and safety of aztreonam, a synthetic monobactam antibiotic from the Squibb Institute for Medical Research (Princeton, NJ) [3], in the treatment of acute uncomplicated gonococcal urethritis in men. Men with gonococcal urethritis were randomly treated with either 1 g of aztreonam or 2 g of spectinomycin im. Of the 112 men so treated, 93 could ultimately be evaluated: 51 who received aztreonam and 42 who received spectinomycin. Both drugs were 100% effective in the treatment of urethritis produced by both penicillin-sensitive and penicillin-resistant strains of gonococci. Furthermore, there were no reported side effects in either group and no laboratory abnormalities attributable to the aztreonam, with the exception of one patient with a minimally elevated level of serum glutamic oxaloacetic transaminase (serum glutamic pyruvic transaminase and alkaline phosphatase levels were normal).(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗
PubMed1983

Protein Kinase Activity Associated with the Extracellular and Occluded Forms of the Baculovirus Autographa californica Nuclear Polyhedrosis Virus.

Protein kinase activity is associated with both the extracellular and the occluded forms of Autographa californica nuclear polyhedrosis virus, a baculovirus. Serine and threonine are the predominant amino acids phosphorylated by the kinase activity associated with both viral forms; no phosphotyrosine was detected. The addition of calcium, cAMP, or cGMP has no apparent effect on the amount of phosphorylation or the substrates phosphorylated.

Journal Article↗