The long-term goal of our research is to improve the overall effectiveness of physicians' time, by improving the information exchange between physicians and chronic-care patients, initially migraine patients. The computer system we are constructing has a partial knowledge base about migraines, common therapies, and common side effects of those therapies. The system consists of two main programs: data collection and explanation. The design of our system is based on empirical data concerning patients' information needs.

Humans↗

PubMed1992

The effect of altitude on umbilical cord blood gases.

OBJECTIVE: Analysis of umbilical cord blood acid-base status has proven useful in the immediate care and resuscitation of the newborn and provides an objective measure of the intrapartum fetal environment. Our study was designed to determine whether there are any significant differences in the acid-base status of neonates delivered at a relatively high altitude of 6000 ft compared with sea-level controls. METHODS: Our study population consisted of 300 women who had undergone spontaneous vaginal delivery after uncomplicated labor; 150 delivered at an institution located at an elevation of 5900 ft and the remainder at an elevation of 87 ft. Exclusion criteria were hypertensive disease, diabetes, suspected fetal growth retardation, fetal distress, meconium-stained amniotic fluid, and chorioamnionitis. All patients received continuous electronic fetal monitoring, and tracings were reviewed by a physician blinded to the umbilical acid-base results. Umbilical cord arterial and venous samples were collected and analyzed within 30 minutes of delivery. RESULTS: Compared with sea-level controls, neonates delivered at high altitude had a significantly higher mean pH with lower mean carbon dioxide pressure values in both arterial and venous specimens (P less than .05). The difference between the mean arterial pH values was 0.026 (P less than .05, 95% confidence interval [CI] 0.015-0.037) and mean venous values was 0.037 (P less than .05, 95% CI 0.027-0.047). There were no significant differences in the arterial or venous oxygen pressure or oxygen saturation values between the study and control groups. There was a significant decrease in the mean birth weight of 320 g (P less than .05, 95% CI 199.5-441.3) and higher pre-delivery hematocrit values (2.4%; P less than .05, 95% CI 1.6-3.2) in the high-altitude population compared with the sea-level group. CONCLUSIONS: Neonates delivered at high altitude have significant alterations in umbilical blood acid-base measurements compared with neonates at sea level. Other significant differences include a lower infant birth weight and a higher maternal hematocrit relative to pregnant women at sea level.

Acid-Base Equilibrium↗

PubMed1992

Moniliformis moniliformis infection has no effect on some behaviors of the cockroach Diploptera punctata.

The behavior of the cockroach Diploptera punctata parasitized with the acanthocephalan Moniliformis moniliformis was examined for parasite-induced alterations. No significant difference in behavior was found between parasitized and unparasitized animals in the following behavioral tests: (1) choice of white/black, horizontal/vertical substrate under light and dark conditions; (2) temporal and directional response to a bright light source; (3) choice between light and dark (photophilia); and (4) activity (time spent moving, distance, and velocity). A comparison of uninfected animals under 2 light conditions showed that light affected the activity of uninfected animals and their response to substrate. Diploptera punctata is the first nondomestic cockroach to be examined for behavioral responses to Moniliformis infection. This is the first report of an arthropod in which acanthocephalan infection has failed to alter behavior under at least some common test conditions.

Animals↗

PubMed1992

Partial attenuation of the pressor response to endotracheal intubation. A comparison of the effects of intravenous clonidine and fentanyl.

In a randomized, double-blind placebo controlled study, intravenous clonidine, fentanyl and saline were compared for both their effect on the cardiovascular response to intubation, and early post-operative pain. The patients treated with fentanyl and clonidine were more sedated and the requirements for induction agents were lower compared to the control group. On intubation, both the active treatments resulted in a smaller increase in both heart rate and mean arterial pressure compared to the control group. There was no significant difference in recovery times in the three groups. Although the time to first request for analgesia was longer in the clonidine group compared to both the fentanyl and saline groups, the difference in morphine requirements between the groups was not significant. The differences between the two active treatments were not significant, and clonidine offered no additional benefits over fentanyl for this purpose.

Adult↗

PubMed1991

A simple method for cloning genes involved in glucan biosynthesis: isolation of structural and regulatory genes for glycogen synthesis in Escherichia coli.

A simple and widely applicable method for cloning genes involved in glucan biosynthesis is described. An Escherichia coli genomic library was prepared in the low-copy plasmid, pLG339, and E. coli transformants from this library were screened by staining with iodine vapor. Colonies that stained darker than the control were isolated and characterized. The three classes of clones that were identified included: (i) plasmids encoding E. coli glycogen biosynthetic (glg) structural genes, (ii) clones that resulted in elevated glycogen levels, but did not encode glg structural genes or enhance the level of the first enzyme of the pathway, ADPglucose pyrophosphorylase (AGPP), and (iii) clones that enhanced the level of AGPP, but did not encode this enzyme. Two clones from the latter class also enhanced glgC'-'lacZ-encoded beta-galactosidase activity, and may encode factors that regulate the expression of glg structural genes. It should be possible to readily clone glycogen biosynthetic genes from other bacterial species via this method. The method could be made specific for a desired glg gene by using a recipient strain that is defective in the gene of interest.

Cloning, Molecular↗

PubMed1991

Effectiveness of routine ultrasonography in detecting fetal structural abnormalities in a low risk population.

OBJECTIVE: To review the efficacy of routine prenatal ultrasonography for detecting fetal structural abnormalities. DESIGN: Retrospective study of the ultrasonographic findings and outcome of all pregnancies in women scanned in 1988-9. SETTING: Maternity ultrasonography department of a district general hospital. SUBJECTS: 8785 fetuses. MAIN OUTCOME MEASURES: Correlation of prenatal ultrasonographic findings with outcome in the neonate. RESULTS: 8733 babies were born during 1988-9, and 52 pregnancies were terminated after a fetal malformation was identified. 8432 (95%) of the fetuses were examined by ultrasonography in the second trimester. 130 fetuses (1.5%) were found to have an abnormality at birth or after termination of pregnancy, 125 of which had been examined in the second trimester. In 93 cases the abnormality was detected before 24 weeks (sensitivity 74.4%, 95% confidence interval to 66.7% to 82.1%. Two false positive diagnoses occurred, in both cases the pregnancies were not terminated and apparently normal infants were born. This gives a specificity of 99.98% (99.9% to 99.99%). The positive predictive value of ultrasonography in the second trimester was 97.9% (92.6% to 99.7%). Of the 125 abnormalities, 87 were lethal or severely disabling; 72 of the 87 were detected by the routine screening programme (sensitivity 82.8%, 73.2% to 90.0%). CONCLUSION: Routine fetal examination by ultrasonography in a low risk population detects many fetal structural abnormalities but can present several dilemmas in counselling.

Congenital Abnormalities↗

PubMed1991

The role of the clinical nurse specialist in biological therapy.

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Humans↗

PubMed1991

Comparison of the 5' flanking regions of the Salmonella typhimurium and Escherichia coli glgC genes, encoding ADP glucose pyrophosphorylases.

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Base Sequence↗

PubMed1991

Histone H4 acetylation in Drosophila. Frequency of acetylation at different sites defined by immunolabelling with site-specific antibodies.

Electrophoresis, Western blotting and immunostaining with antibodies specific for histone H4 acetylated at lysines 5, 8, 12, or 16, were used to define patterns of H4 acetylation in cell lines from humans (HL60) and the fruit fly Drosophila (S2, Kc). In human cells, the mono-acetylated isoform H4Ac1 is acetylated predominantly at just one of the four possible lysine residues, lysine 16. This is the first step in the progressive acetylation of H4. In contrast, in Drosophila, H4Ac1 is acetylated at lysines 5, 8, or 12 with approximately equal frequency. Fundamental differences appear to exist in control of H4 acetylation in different species, despite the evolutionary conservation of acetylation sites.

Acetylation↗

PubMed1991

Differential effects of unsaturated fatty acids on modulation of endotoxin-induced tissue factor activation in cultured human leukemia U937 cells.

We examined the direct effects of unsaturated fatty acids, oleic (18:1 n-9), linoleic (18:2 n-6), eicosapentaenoic (20:5 n-3) and docosahexaenoic (22:6 n-3) on tissue factor (TF) activity in the human leukemia monocytic U937 cell line. After exposing cells to fatty acids for 16 h, there were no significant effects on either TF activity or its activation induced by bacterial endotoxin (LPS). When the cells were primed with fatty acids for 24 h, 48 h or 72 h, the TF activity remained essentially unchanged. However, the extent of TF-activation induced by LPS depended on the length of priming, and the dose and the degree of unsaturation of the fatty acids to which cells were exposed. After a 72-h priming, 18:1 produced 40-60 per cent elevation in LPS-challenge. In contrast, approximately 20-50 per cent reduction in LPS-challenge was achieved by 18:2, 20:5 and 22:6 at high concentrations. The results suggest that chronic exposure of U937 cells to unsaturated fatty acids leads to modulation of the TF-activation in response to LPS.

Endotoxins↗

PubMed1991

13C NMR spectroscopic analysis of phospholipid metabolism in adrenal chromaffin cells.

Phosphatidylcholine (PC) metabolism in bovine adrenal chromaffin cells has been studied in vivo with 100 MHz 13C NMR spectroscopy. The incorporation of 13[CH3]choline was examined in cells embedded in 1% agarose strands and perfused at 37 degrees C. The pattern of 13C NMR spectroscopy. The incorporation of [13CH3]choline incorporation into PC of suspension cultures of chromaffin cells. The chemical shifts of labelled carbons in [13CH3]choline before and after their incorporation into PC are identical (ca 56.4 ppm). Incorporated [13CH3]choline can be released from the cells by phospholipase D which reduces the cellular PC signal by greater than 85%, indicating that a major fraction of the labelled PC is on the external membrane surface. This application of NMR spectroscopy provides a basis for direct measurement of the in vivo metabolism of PC in functioning adrenal chromaffin cells.

Adrenal Glands↗