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Biomedical subjects

S Evans

Publications and source records attributed to S Evans.

At least 181 records · Page 10Linked to original sources
PubMed1995

Proteinases of rat mast cells. Peritoneal but not intestinal mucosal mast cells express mast cell proteinase 5 and carboxypeptidase A.

Six basic proteins of 26 to 38 kDa with isoelectric points (pI) > or = 8.5 were abundant in proteins separated by two-dimensional SDS-PAGE from adult rat peritoneal mast cells (MC). One was identified previously as rat mast cell proteinase (RMCP) 1, a chymase of 26 to 28 kDa, pI > 9.0. Microsequence analyses showed that two polypeptides of about 29 and 30 kDa had NH2 terminal amino acid sequences homologous to mouse MC proteinase 5 (MCP-5), whereas the amino terminals of the 33, 35, and 36 kDa proteins were homologous to MC carboxypeptidase A (MC-CPA). Rabbit Abs produced against synthetic peptides of the identified NH2 terminal sequences were used in immunoblot studies. At least three proteins reacted with Abs to MC-CPA, whereas Abs to MCP-5 detected three adjacent polypeptides, rather than just the two identified by using microsequence analysis. Removal of oligosaccharide side chains using peptide:N-glycosidase F reduced the heterogeneity of each set of three polypeptides (MCP-5 and MC-CPA) to a band of each protein of a lower M(r). The serine proteinase inhibitor [3H]diisopropylfluorophosphate ([3H]DFP) bound to a proteinase of 30 to 35 kDa, which is probably MC tryptase (pI < or = 6.0). Immunoblot analysis of proteins from intestinal mucosal mast cells showed RMCP-2, but not RMCP-1, MCP-5, or MC-CPA. This is the first report of MCP-5 in the rat and of clearly distinguishable glycosylated forms of MC CPA. These proteinases appear to be restricted in their distribution to selected MC populations, but little is known about their functions.

Amidohydrolases↗
PubMed1995

Improving outcome for Western Australian infants with birthweights 500-999 g.

OBJECTIVE: To assess changes in survival and disability in liveborn extremely low birthweight infants (500-999 g) in Western Australia, 1980-1987. DESIGN: Cohort study comparing two periods, 1980-1983 (P1) and 1984-1987 (P2). PARTICIPANTS: All 586 liveborn extremely low birthweight infants in WA in 1980-1987 (266 in P1, 320 in P2). MAIN VARIABLES EXAMINED: Birthweight, place of birth, age at death, neurosensory examination findings and scores on the Griffiths Mental Development Scales or other standardised test results. RESULTS: 482/586 infants (82%) were born at King Edward Memorial Hospital (KEMH), a level III referral centre, and a further 4% were transferred there after birth. The proportion born at KEMH increased from 78% in P1 to 86% in P2. Survival increased from 35% to 43% overall. In those below 800 g birthweight, survival doubled from 14% to 29%. There was no change in the age at death for non-survivors. Follow-up information was known for 222 of the 229 survivors at median ages of 46 months (P1) and 43 months (P2). Disability rates in infants below 800 g birthweight remained static (P1, 26%; P2, 28%), but fell in those of 800-999 g birthweight from 24% to 13%. Overall, survival free of disability increased from 26% to 34%. CONCLUSION: Increased survival rates occurred without any increase in the rate or severity of disability in survivors.

Cerebral Palsy↗
PubMed1995

Further development of the locus control region/murine erythroleukemia expression system: high level expression and characterization of recombinant human calcitonin receptor.

In order to demonstrate the potential of the LCR/MEL expression system for the expression of seven-transmembrane helix receptors the human calcitonin receptor (hCTR) has been cloned and expressed at high levels in this system. Using the newly developed single-step expression vectors pEV and pNV, stable recombinant MEL cells which express the hCTR at approximately 6 pmol of receptor/mg of total cell protein (60 pmol/mg of membrane protein), or 1.9 x 10(6) receptors per cell, have been generated. Ligand binding studies have shown that the cloned receptor expressed in MEL cells has properties which are indistinguishable from those of the native receptor in T47D cells. It is suggested that MEL cells expressing seven-transmembrane helix receptors provide an efficient and readily attainable source of material for ligand binding experiments using these receptors.

Animals↗
PubMed1995

Comparison of serum C-reactive protein concentrations for laparoscopic versus open cholecystectomy.

In an attempt to quantify the difference in tissue damage between open cholecystectomy (OC) and laparoscopic cholecystectomy (LC), we have compared in a prospective manner the pre- and post-operative concentrations of serum C-reactive protein (CRP) in 17 patients undergoing LC and 13 patients undergoing OC. In addition, we measured the pre- and postoperative white blood cell counts (WBC), the postoperative body temperature, and the postoperative duration of hospitalization. There were no differences in the preoperative serum CRP concentrations--5.9 +/- 2.62 mg/l (mean +/- SD) for the LC group and 6.12 +/- 2.38 mg/l for the OC group. Serum CRP rose markedly following OC compared to that of patients who underwent LC (128.6 +/- 45.1 mg/l vs 26.8 +/- 10.5 mg/l) (P < 0.001). There were also significant differences in the postoperative WBC count (14,000 +/- 2,900 cells for the OC group vs 10,600 +/- 3,000 cells for the LC group), the postoperative body temperature (37.5 +/- 0.3 degrees C vs 37.0 +/- 0.3 degrees C), and the postoperative hospital stay (5.5 +/- 1.5 days vs 1.9 +/- 0.9 days). There was no correlation between serum CRP concentrations and the other postoperative parameters. These results provide us with biochemical evidence supporting the clinical observation that LC is far less traumatic to the patient than OC.

Adult↗
PubMed1995

Selective distal splenorenal shunts for intractable variceal bleeding in pediatric portal hypertension.

The treatment of portal hypertension in the pediatric population has undergone an evolution toward less invasive methods of care. With the advent of endoscopic sclerotherapy, surgery is less common in the acute care of these patients. Few reports deal with the role of portosystemic shunting in the emergent management of variceal hemorrhage in children. To address this issue, the authors studied the medical records of all pediatric patients at their institution who underwent placement of a shunt for portal hypertension during the last 10 years. Nine patients underwent a total of 10 emergent or semiurgent shunting procedures. Seven were boys and two were girls. Six patients had portal hypertension as a result of intrahepatic disease. Two had extrahepatic portal vein thrombosis. Five children had abnormal hepatic function. The median age at the time of the procedure was 9 years. The indication for surgical shunting in all cases was gastrointestinal hemorrhage not responsive to sclerotherapy. Eight patients underwent emergent distal splenorenal shunts (DSRS), and two underwent a nonselective mesocaval shunt, with one undergoing both. Postoperatively all patients had cessation of bleeding. Operative mortality was zero. Early complications included ascites (3), small bowel obstruction (1), and hepatorenal syndrome (1). The child who underwent a nonselective shunt procedure had encephalopathy. Two DSRS thrombosed, requiring reexploration; eight shunts remained patent. Three patients eventually had orthotopic liver transplantation (OLT) because of progressive hepatic failure. Two children died; neither death was shunt related.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Assessing clinicians' consultation with people with profound learning disability: producing a rating scale.

This paper describes the development of a scale for assessing clinicians' communication with people with profound learning disability. Four psychiatrists and four nurses were assessed completing three simple non-invasive clinical procedures--blood pressure, pulse and axillary temperature--with people with profound learning disability. Videotaped assessment of consultations was performed by three experienced speech and language therapists using a previously designed scale for analysing encounters with people with mild learning disability. This led to the production of a new scale specifically for people with profound learning disability. A significant inter-rater reliability was found between the three speech therapists for total scores (rater a-b, corr = 0.654, P = 0.006; rater a-c, corr = 0.795, P = 0.0001: rater b-c, corr = 0.673, P = 0.004). Significant reliability between raters was also found for the subsections of verbal behaviour and non-verbal behaviour.

Blood Pressure↗
PubMed1995

Sequence-specific DNA binding by NIT4, the pathway-specific regulatory protein that mediates nitrate induction in Neurospora.

The expression of the structural genes nit-3 and nit-6, which encode the nitrate assimilatory enzymes nitrate reductase and nitrite reductase, respectively, is highly regulated by the global-acting NIT2 regulatory protein. These structural genes are also controlled by nitrogen catabolite repression and by specific induction via nitrate. A pathway-specific regulatory protein, NIT4, appears to mediate nitrate induction of nit-3 and of nit-6. The NIT4 protein, composed of 1090 amino acids, contains a putative GAL4-like Cys-6 zinc cluster DNA-binding motif, which is joined by a short segment to a stretch of amino acids that appear to constitute a coiled-coil dimerization domain. Chemical crosslinking studies demonstrated that a truncated form of NIT4 forms homodimers. Mobility-shift and DNA-footprinting experiments have identified two NIT4-binding sites of significantly different strengths in the promoter region of the nit-3 gene. The stronger binding site contains a symmetrical octameric sequence, TCCGCGGA, whereas the weaker site has a related sequence. Sequences related to this palindromic element can be found upstream of the nit-6 gene.

Amino Acid Sequence↗
PubMed1995

Urticaria from allergy to a purified human anti-Rh antibody preparation.

This case presentation describes a young woman who developed generalized urticaria after receiving the human anti-RhD(D) preparation, WinRho, intravenously. Allergy skin tests and the radioallergosorbent test (RAST) for IgE antibodies to the human anti-D immunoglobulin preparation were positive. Further studies using high-pressure liquid chromatography and protein A column chromatography implicated a nonimmunoglobulin low-molecular-weight contaminant. This case report illustrates an allergic reaction to a highly purified human immunoglobulin preparation, and demonstrates approaches to assessment of such a reaction.

Adult↗
PubMed1995

Morphine increases synchronous ventilation in preterm infants.

OBJECTIVE: To examine the short-term cardiorespiratory effects of intravenous morphine infusion in ventilated preterm infants. METHODOLOGY: A randomized double-blind placebo-controlled trial in a neonatal intensive care unit. Twenty-six preterm infants (29-36 weeks gestation) with hyaline membrane disease requiring ventilatory assistance on the first day after birth were included in the study. A loading dose of morphine 100 micrograms/kg over 30 min followed by a continuous intravenous infusion at 10 micrograms/kg per hour was given. Primary measures were heart rate, blood pressure, respiratory rate and interaction of spontaneous respiration with mechanical ventilation. Secondary measures were durations of oxygen therapy, ventilator therapy and hospitalization as well as incidence of bronchopulmonary dysplasia, periventricular haemorrhage and pneumothorax. RESULTS: Morphine-treated infants spent a significantly greater percentage of total ventilated time breathing in synchrony with their ventilators (median [IQ] = 72[58-87] vs 31[17-51]%; P = 0.0008). Heart rate and respiratory rate, but not blood pressure, were reduced in morphine-treated infants. Duration of oxygen therapy was reduced (median [IQ] = 4.5[3-7] vs 8[4.75-12.5] days; P = 0.046). CONCLUSIONS: Intravenous morphine infusion increases synchronicity of spontaneous and ventilator-delivered breaths in preterm infants. Morphine reduces heart rate and respiratory rate without reducing blood pressure, and may help to reduce duration of oxygen therapy in preterm infants with hyaline membrane disease.

Double-Blind Method↗
PubMed1995

Effect of a postural support nappy on 'flattened posture' of the lower extremeties in very preterm infants.

OBJECTIVE: To determine whether the use of a postural support nappy (PSN) would reduce the features of 'flattened posture' in the lower extremities of infants < 31 weeks gestation who are nursed prone. METHODOLOGY: Randomized, observer blind, controlled trial conducted at King Edward Memorial Hospital for Women, Perth, Western Australia. Infants were randomly assigned and stratified by gestational age to be nursed in a conventional nappy (n = 29) or a PSN (n = 31) when in the prone position. The features of 'flattened posture' were measured as angles and assessed by blinded observers prior to commencement of the intervention, 4 weeks post intervention, then bi-weekly until discharge. RESULTS: A significant reduction in the features of 'flattened posture' occurred in the PSN group after 4-6 weeks of intervention and stabilized by 8 weeks until discharge. No changes were detected in the control group. No significant difference was observed between infants < 29 weeks gestation compared to infants of 29-30 weeks gestation in either treatment group. CONCLUSIONS: Use of the PSN in infants < 31 weeks gestation who are nursed in the prone position significantly reduces the features of 'flattened posture' in the lower extremities. This is of benefit in the short term, and follow up of these infants into childhood will demonstrate whether the long-term effects of 'flattened posture' can be prevented.

Chi-Square Distribution↗
PubMed1995

Screening for the small fetus: a study of the relative efficacies of ultrasound biometry and symphysiofundal height.

In this study 3 different methods of screening for birth-weight < 10th percentile in pregnancy were evaluated both individually and in combination; 1,135 women with singleton pregnancies were studied. Measurements of symphysiofundal height by tape measure, and amniotic fluid index and fetal abdominal circumference by ultrasound imaging, were made at 18, 24, 28, 34 and 38 weeks. At none of these gestational ages did amniotic fluid index perform well as a screening test for birth-weight < 10th percentile. Combining the tests, using symphysiofundal height to select a group at high risk who then had a fetal abdominal circumference measurement, reduced the false positive rate but significantly decreased the percentage of infants diagnosed. The results of this study confirm that the most appropriate antenatal diagnostic test for birth-weight <10th percentile is ultrasound measurement of fetal abdominal circumference. Selecting pregnancies at risk by clinical measurement of symphysiofundal height will provide a lower false positive rate than a policy of performing ultrasound on all pregnancies during the third trimester, but will also reduce the sensitivity.

Adult↗
PubMed1995

Obstetric experience of female medical practitioners as patients.

The objective was to investigate the obstetric experience of South Australian medical practitioners, and in addition, to assess whether the reported increase in adverse pregnancy outcomes among medical practitioners in America occurs in South Australia. A population-based postal survey of the entire registered female medical population of South Australia was carried out. Comparison was made with randomly selected individually matched pregnant South Australian control women. No significant increase in any complications was found when compared with a case-controlled group matched for age, parity, year of delivery, and social class. There was a strongly significant increase in their interest in pregnant women and empathy with the difficulties of pregnancy after their own deliveries. The reported increase in complications in American women may be due to the working conditions of those studied. Further assessment of obstetric outcome should consider the individual women's working conditions, including stress. The South Australian group in general reported more difficulties with the postpartum period than the pregnancy itself, and this is the area where more research, and practical assistance should be concentrated.

Case-Control Studies↗
PubMed1995

Identification of multiple human calcitonin receptor isoforms: heterologous expression and pharmacological characterization.

The human breast carcinoma cell line T47D is known to express high-affinity calcitonin receptors (CTRs). PCR amplification of the CTR cDNA from T47D mRNA resulted in the identification of two different cDNAs that encode distinct receptor isoforms, h alpha CTR and h beta CTR. The two cDNAs are identical except that the h alpha CTR cDNA contains a 48 bp insert sequence that encodes a 16 amino acid domain in the first cytosolic loop of the receptor. Stable transfection of each receptor cDNA into murine erythroleukaemia (MEL) cells resulted in the expression of receptors with high affinity for radiolabelled salmon calcitonin (h alpha CTR Kd 0.09 nM, h beta CTR Kd 0.12 nM). Ligand competition binding studies did not reveal any significant pharmacological difference between the receptor isoforms. In transfected MEL cells and COS-1 cells the h beta CTR isoform was expressed at tenfold higher levels than the h alpha CTR. A reporter gene assay that monitored the coupling of CTR to adenylate cyclase by increases in beta-galactosidase activity indicated that both receptors were able to stimulate cyclic AMP production in response to ligand binding.

Adenylyl Cyclases↗