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M J Turner

Publications and source records attributed to M J Turner.

At least 37 records · Page 2Linked to original sources
PubMed2001

T-cell antigen discovery (T-CAD) assay: a novel technique for identifying T cell epitopes.

The identification of T cell epitopes is a critical step in evaluating and monitoring T cell mediated immune responses. Here, we describe a novel technique for simultaneously identifying class I and class II MHC restricted epitopes using a one-step protein purification system. This method uses Ni/chelate coated magnetic beads and magnetic separation to isolate poly-histidine tagged recombinant antigen from bacterial lysates. These beads, once coated with antigen, are also used to deliver antigen to APC where it is processed and presented to T cells. A colorimetric assay and ovalbumin specific, lacZ inducible, T cell hybridomas were used to validate the system. Further, using PSA specific hybrids, generated from T cells isolated from PSA secreting tumors, both class I and class II MHC restricted epitopes of PSA were identified. Additional characterization has shown that these peptides contribute significantly to the overall PSA specific response in vivo, and may represent the dominant epitopes of PSA.

Animals↗
PubMed2001

Fetal DNA in maternal circulation of first-trimester spontaneous abortions.

OBJECTIVE: To establish whether fetal DNA can be identified in the maternal circulation in first-trimester spontaneous abortions. METHODS: Women with confirmed spontaneous abortions and no histories of previous pregnancy were recruited. Peripheral venous blood samples were obtained and DNA extracted. Real-time quantitative polymerase chain reaction was done using SRY and beta-actin systems for calculating fetal and total DNA, respectively. RESULTS: Of 25 women, SRY-specific signals were detected in 11 indicating that the abortions were male. The remaining 14 were negative for the SRY gene. Women with positive results were of similar gestational age to those who were negative (mean 68.4 and 69.0 days). Fetal:total DNA ratio was calculated for positive samples and ranged from 15.8 to 360.1 x 10(+3). Mean ratio was 99.4 x 10(+3) and median was 67.5 x 10(+3). CONCLUSION: Fetal DNA is present in the maternal circulation of first-trimester spontaneous abortions.

Abortion, Spontaneous↗
PubMed2001

An audit of patients investigated by laparoscopy and dye for infertility.

We reviewed 100 laparoscopy and dye studies performed in the Coombe Women's Hospital to determine whether recommended guidelines were followed for the investigation of infertility. Individual chart review provided information on patient demographics, preoperative investigations, operative findings and outcome. Preoperative assessment of ovulation or a semen analysis was not performed in 20 and 30 women, respectively. At laparoscopy bilateral tubal patency was demonstrated in 86 patients, three patients had bilateral blocked tubes and 11 patients had unilateral tubal occlusion. In 54% of patients there were no other additional findings. Following laparoscopy five women were referred for in vitro fertilisation and five patients had further surgery as a result of the findings at laparoscopy. In addition, three women were treated for hyperprolactinaemia and three male partners were referred for further investigation. Within one year 20 women became pregnant, 18 delivered a baby and two had a miscarriage.

Journal Article↗
PubMed2001

Is fetal abdominal subcutaneous fat comparable with established indices of growth restriction?

The purpose of this study was to determine if measurement of the abdominal subcutaneous fat antenatally using ultrasound is comparable to other established indices of fetal growth restriction (FGR). One hundred women with singleton pregnancies had an ultrasound scan within 1 week of delivery at term. Ultrasound measurements included abdominal circumference (AC), liquor assessment by amniotic fluid index (AFI) and abdominal subcutaneous fat thickness (FAB). After delivery,infants were weighed and skinfold thickness at triceps and subscapular sites measured. Ponderal index was also calculated. Infants with an abdominal subcutaneous fat measurement antenatally of 5 mm or less (n = 41) were more likely than those with a fat measurement of more than 5 mm (n = 59) to have an AFI < 8 cm (P < 0.001) and to have an AC < 10th centile (P < 0.001). Decreased antenatal fat thickness was associated postnatally with a lower mean ponderal index (24.2 kg/m3 vs. 25.5 kg/m3, P < 0.02) and a decreased skinfold thickness (4.84 vs. 5.55 mm, P < 0.003 and 3.88 vs. 4.37, P < 0.03 for triceps and subscapular, respectively). This study shows that fetal abdominal subcutaneous fat measurement correlates with established predictors of fetal nutrition such as liquor volume, abdominal circumference, ponderal index, triceps and subscapular skinfold thickness.

Journal Article↗
PubMed2001

Changes and continuities in the determinants of older adults' voter turnout 1952-1996.

PURPOSE: The goal of this project was to examine the factors related to the high level of voter turnout among older adults and how these factors have changed across the past 50 years. The study builds on previous research efforts by combining individual level analyses from three nationally representative surveys. DESIGN AND METHODS: We examined voter turnout among older citizens using the American National Election Studies (ANES) 1952-1996, the Current Population Studies (CPS) 1972-1996, and the General Social Surveys (GSS) 1972-1996. Logit regression identified significant factors that contribute to or detract from voting in presidential elections. RESULTS: Included in the extensive results, we found that being married, attending church, and contact by political operatives (since the 1980 election) contributed positively to older voters' turnout, whereas living in the South was a negative predictor. IMPLICATIONS: Triangulating data sources, we are able to utilize the strengths of each study-providing an overview of the determinants of voter turnout and understanding of the changes related to older Americans' turnout in presidential elections.

Adolescent↗
PubMed2001

Interstrain variation in murine aerobic capacity.

PURPOSE: The contribution of genetic factors to aerobic capacity is unknown. The purpose of this study was to measure maximal aerobic performance among inbred strains of mice to provide basic heritability estimates. METHODS: Eight female mice, 8 to 10 wk old, in 10 inbred strains (A/J, AKR/J, Balb/cJ, C(3)H/HeJ, C57Bl/6J, C57L/J, C(3)Heb/FeJ, CBA/J, DBA/2J, and SWR/J) were run on a treadmill until exhaustion. The protocol started at 22 m.min(-1) and increased in speed approximately 6 m.min(-1) every 4 min. After 4 min at 42.4 m.min(-1), the grade was increased 2% every 4 min thereafter until the mouse could not run off of the shock grid (150 V; 1.5 mA). RESULTS: There were significant differences between inbred strains in maximal duration of exercise accomplished (P < 0.0001). The order of strain-specific exercise duration was Balb/cJ > SWR/J > CBA/J > C57L/J > C3H/HeJ > C3Heb/FeJ > C57Bl/6J > AKR/J > DBA/2J > A/J. Two measures of heritability in the broad sense, intraclass correlation (0.73), and the coefficient of genetic determination (0.58) were both significant. CONCLUSION: These data indicate that there is a strong genetic contribution to aerobic capacity in mice.

Animals↗
PubMed2000

Comparative sensitivity of various faecal culture methods and ELISA in dairy cattle herds with endemic Johne's disease.

In three New South Wales dairy cattle herds with endemic Johne's disease, prevalence rates by faecal culture were determined to be 12, 18 and 22%, respectively. Whole herd faecal culture was shown to detect markedly more infected cattle than whole herd testing by the EMAI absorbed ELISA, particularly in the two herds with greatest prevalence. In the three study herds, five methods for whole herd faecal culture were compared in each. These included two methods based on primary culture on Herrold's egg yolk medium with mycobactin J (HEYM): (1) conventional decontamination with sedimentation and primary culture on HEYM; (2) Whitlock decontamination and culture on HEYM. The remaining three methods were based on radiometric (BACTEC) culture: (3) decontamination and filtration to BACTEC medium; (4) modified Whitlock decontamination to BACTEC medium and (5) Whitlock decontamination to BACTEC medium. For BACTEC cultures, two methods were compared as confirmatory tests for Mycobacterium paratuberculosis: mycobactin dependence on conventional subculture to HEYM and IS900 PCR analysis of radiometric media. Among 179 cattle tested simultaneously by all five culture methods, 38 cattle were confirmed to be shedding M. paratuberculosis. In identifying shedder cattle, method 5 was the most sensitive, followed by methods 2, 4, 1, and 3 was the least sensitive. The number of BACTEC cultures confirmed by mycobactin dependence or PCR was similar.

Animals↗
PubMed2000

Obstetric and neonatal outcome of babies weighing more than 4.5 kg: an analysis by parity.

OBJECTIVES: To analyse by parity the obstetric and neonatal outcome of babies delivered weighing more than 4.5 kg. METHODS: All deliveries resulting in a baby weighing more than 4.5 kg, in the 5 years from 1991 to 1995, were identified using a computerised database. The following variables confined to singleton, cephalic pregnancies were recorded: mode of delivery, duration of labour, incidence of shoulder dystocia and admission to the neonatal centre. Outcome measures in primigravidae and multigravidae were compared using the Epi Info package (WHO, Version 6.0b January 1997). RESULTS: There were 32,834 deliveries over the study period and 828 (2.5%) weighed more than 4.5 kg. Birthweight more than 4.5 kg occurred in 1.6% (n=198) of primigravidae and 3.1% (n=630) of multigravidae (P<0.05). Primigravidae had a higher risk of prolonged labour (27.7% vs. 4.9%), operative vaginal delivery (32% vs.9%) and emergency caesarean section (24.2% vs. 5.7%) compared to multigravidae. When delivering a macrosomic baby, primigravidae had a higher incidence of prolonged labour (27% vs. 7.9%), operative vaginal delivery (32% vs.25%) and emergency caesarean section (24.2% vs. 5.7%) compared to normal weight babies. The incidence of shoulder dystocia and elective caesarean section were similar in both primigravidae and multigravidae. CONCLUSIONS: Macrosomic infants have an increased incidence of prolonged labour, operative vaginal delivery and emergency caesarean section compared with normal weight babies and these complications are more pronounced in primigravidae compared to multigravidae. Shoulder dystocia occurs with equal frequency in primigravidae and multigravidae. The poor antenatal predictability of macrosomia, the high rate of vaginal delivery and the low incidence of shoulder dystocia would not support the use of elective caesarean section for delivery of the macrosomic infant either in primigravidae or multigravidae.

Birth Weight↗
PubMed2000

Hysterosalpingocontrastsonography in clinical practice.

The aim of this study was to review the indication, source of referral and findings at hysterosalpingocontrastsonography (HyCoSy) of the first 100 patients referred for this new service in the gynaecological outpatients department of the Coombe Women's Hospital, Dublin. Of the first 100 women referred for HyCoSy, the indication for referral was investigation of infertility in 72%, recurrent miscarriage in 22% and other reasons in 6%. Sixty-four women were referred from general gynaecological clinics, 29 from the specialised infertility clinic and seven women were referred from other hospitals. The procedure was completed in 97% of cases and tubal patency successfully assessed in 95%. Saline hysterosonography was performed in 96 cases. Tubal assessment with Echovistt showed bilateral tubal patency in 73%, bilateral occlusion in 10% and unilateral patency in 12%. All women were discharged within 30 minutes of the procedure. We concluded that hysterosalpingocontrastsonography is an easily introduced, successful outpatient technique, which is well tolerated by women and provides clinically relevant information in women with infertility or recurrent miscarriage.

Journal Article↗
PubMed2000

Are the immediate complications of conisation with the large loop similar to those with the knife?

One hundred patients underwent conisation with large loop excision of the transformation zone. The overall immediate complication rate was 6%. There were no preoperative complications. Three patients were treated with antibiotics for infection and three patients had a secondary haemorrhage. No patient required a blood transfusion or cervical suturing and no patient returned to the operating theatre.

Journal Article↗
PubMed2000

Estimation of pulmonary blood flow from sinusoidal gas exchange during anaesthesia: a theoretical study.

We simulated the use of simultaneous sinusoidal changes of inspired O2 and N2O (Williams et al., J Appl Physiol, 1994; 76: 2130-9) at fractional concentrations up to 0.3 and 0.7, respectively, to estimate FRC and pulmonary blood flow (PBF) during anaesthesia, using O2 as an insoluble indicator. Hahn's approximate equations, which neglect the effect of pulmonary uptake and excretion on expiratory flow, estimate dead space and alveolar volume (VA) with systematic errors less than 10%, but yield systematic errors in PBF which are approximately proportional to FIN2O in magnitude. A correction factor (1 - P)-1 for Hahn's equations for PBF (where P is the mean partial pressure of the soluble indicator) reduces the dependence of PBF estimates of FIN2O, and the solution of equations describing the simultaneous mass balance of both indicators yields accurate results for a wide range of mean FIN2O. However, PBF estimates are sensitive to measurement errors and a third gas must be present to ensure that the indicator gases behave independently.

Anesthesia↗
PubMed2000

Effect of endurance exercise training on left ventricular size and remodeling in older adults with hypertension.

BACKGROUND: It is not known whether exercise training can induce a reduction of blood pressure (BP) and a regression of left ventricular hypertrophy (LVH) in older hypertensive subjects. This study was designed to determine whether endurance exercise training, by lowering BP, can induce regression of LVH and left ventricular (LV) concentric remodeling in older hypertensive adults. METHODS: We studied 11 older adults with mild to moderate hypertension (BP 152.0 +/- 2.5/91.3 +/- 1.5 mm Hg, mean +/- SE), 65.5 +/- 1.2 years old, who exercised for 6.8 +/- 3.8 months. Seven sedentary hypertensive (BP 153 +/- 3/89 +/- 2 mm Hg) subjects, 68.5 +/- 1 years old, served as controls. LV size and geometry and function were assessed with the use of two-dimensional echocardiography. RESULTS: Exercise training increased aerobic power by 16% (p < .001), and it decreased systolic (p < .05) and diastolic (p < .05) BP, LV wall thickness (from 12.8 +/- 0.4 mm to 11.3 +/- 0.3 mm; p < .05), and the wall thickness-to-radius (h/r) ratio (from 0.48 +/- 0.02 to 0.41 +/- 0.01; p < .05). There were no significant changes in the controls. The changes in LV mass index (deltaLVMI) were different between the two groups. LV mass index decreased in the exercise group (deltaLVMI - 14.3 +/- 3.3 g) but not in the controls (deltaLVMI 1.4 +/- 4.1 g; p = .009). A multiple stepwise regression analysis showed that among clinical and physiological variables including changes in resting systolic BP, aerobic power, body mass index, and systolic BP during submaximal and maximal exercise, only the reduction in resting systolic BP correlated significantly with a regression of concentric remodeling (delta h/r ratio r = .80; p = .003). The other variables did not add to the ability of the model to predict changes in the h/r ratio. CONCLUSIONS: The data suggest that exercise training can reduce BP and induce partial regression of LVH and LV concentric remodeling in older adults with mild or moderate hypertension.

Aged↗
PubMed2000

Primate pleuroesophageal tissue barrier frequency response and esophageal pressure waveform bandwidth in health and acute lung injury.

BACKGROUND: Dynamic intraesophageal pressure (Pes) is used to estimate intrapleural pressure (Ppl) to calculate lung compliance and resistance. This study investigated the nonhuman primate Ppl-Pes tissue barrier frequency response and the dynamic response requirements of Pes manometers. METHODS: In healthy monkeys and monkeys with acute lung injury undergoing ventilation, simultaneous Ppl and Pes were measured directly to determine the Ppl-Pes tissue barrier amplitude frequency response, using the swept-sine wave technique. The bandwidths of physiologic Pes waveforms acquired during conventional mechanical ventilation were calculated using digital low-pass signal filtering. RESULTS: The Ppl-Pes tissue barrier is amplitude-uniform within the bandwidth of conventional Pes waveforms in healthy and acute lung injury lungs, and does not significantly attenuate Ppl-Pes signal transmission between 1 and 40 Hz. At Pes frequencies higher than conventional clinical regions of interest the Ppl-Pes barrier resonates significantly, is pressure amplitude dependent at low-pressure offsets, and is significantly altered by acute lung injury. Allowing for 5% or less Pes waveform error, the maximum Pes bandwidths during conventional ventilation were 1.9 Hz and 3.4 Hz for physiologic and extreme-case waveforms in healthy lungs and 4.6 Hz and 8.5 Hz during acute lung injury. CONCLUSIONS: In monkeys, the Ppl-Pes tissue barrier has a frequency response suitable for Ppl estimation during low-frequency mechanical ventilation, and Pes manometers should have a minimum uniform frequency response up to 8.5 Hz. However, the Ppl-Pes tissue barrier adversely affects the accurate estimation of dynamic Ppl at high frequencies, with varied airway pressure amplitudes and offsets, such as the Ppl encountered during high-frequency oscillatory ventilation.

Acute Disease↗
PubMed2000

Inflammatory cloacogenic polyp mimicking anorectal malignancy.

Inflammatory cloacogenic polyp is a rare condition arising from the transitional zone of the anorectal junction. It is benign but may macroscopically resemble anorectal malignancy. Inflammatory cloacogenic polyp was diagnosed in two patients with rectal bleeding and polypoid growths at the anorectal junction. The lesions were best visualized with an endoscope retroflexed in the rectum. Accurate diagnosis was dependent on histological examination. The histological similarities to solitary rectal ulcer syndrome and other mucosal prolapse conditions are discussed, and the literature on inflammatory cloacogenic polyp and its management reviewed.

Colonoscopy↗
PubMed2000

Enhanced inotropic response to dobutamine in strength-trained subjects with left ventricular hypertrophy.

To determine whether strength-trained individuals with physiological concentric left ventricular (LV) hypertrophy exhibit enhanced inotropic responses to catecholamines, we studied 11 bodybuilders, aged 33.0 +/- 2 (SE) yr old, and 10 sedentary healthy subjects, aged 31.3 +/- 2.4 yr old, at baseline and during infusion of incremental doses of dobutamine after atropine. The bodybuilders had larger LV mass, posterior wall and septal wall thicknesses, and wall thickness-to-radius ratio, assessed with two-dimensional echocardiography, than did the sedentary subjects. There was a significant correlation between LV mass and lean body mass irrespective of training status. Baseline LV fractional shortening was similar in the two groups. There was a greater inotropic response to dobutamine in the strength-trained individuals, as evidenced by a steeper slope of the fractional shortening-end-systolic wall stress relationship with a higher y-axis intercept and by a shallower end-systolic wall stress-end systolic diameter relationship without changes in end-diastolic diameter. The heart rate response to dobutamine was attenuated in the strength-trained athletes. There was a significant correlation (r = 0.604, P < 0.05) between the inotropic sensitivity to dobutamine and LV mass normalized for lean body mass in the bodybuilders. The data suggest that concentric LV physiological hypertrophy in the resistance-trained individuals is associated with enhanced inotropic but not chronotropic responses to catecholamines.

Adrenergic beta-Agonists↗
PubMed1999

Differential cytokine and chemokine gene expression by human NK cells following activation with IL-18 or IL-15 in combination with IL-12: implications for the innate immune response.

NK cells constitutively express monocyte-derived cytokine (monokine) receptors and secrete cytokines and chemokines following monokine stimulation, and are therefore a critical component of the innate immune response to infection. Here we compared the effects of three monokines (IL-18, IL-15, and IL-12) on human NK cell cytokine and chemokine production. IL-18, IL-15, or IL-12 alone did not stimulate significant cytokine or chemokine production in resting NK cells. The combination of IL-18 and IL-12 induced extremely high amounts of IFN-gamma protein (225 +/- 52 ng/ml) and a 1393 +/- 643-fold increase in IFN-gamma gene expression over those in resting NK cells. IL-15 and IL-12 induced less IFN-gamma protein (24 +/- 10 ng/ml; p < 0.007) and only a 45 +/- 19-fold increase in IFN-gamma gene expression over those in resting NK cells. The CD56bright NK cell subset produced significantly more IFN-gamma following IL-18 and IL-12 compared with CD56dim NK cells (p < 0.008). However, the combination of IL-15 and IL-12 was significantly more potent than that of IL-18 and IL-12 for NK cell production of IL-10, macrophage inflammatory protein-1alpha, macrophage inflammatory protein-1beta, and TNF-alpha at the protein and transcript levels. Granulocyte-macrophage CSF was optimally induced by IL-15 and IL-18. Resting CD56+ NK cells expressed IL-18R transcript that was up-regulated by IL-12 or IL-15. Our results show that distinct cytokine and chemokine patterns are induced in NK cells in response to different costimulatory signals from these three monokines. This suggests that NK cell cytokine production may be governed in part by the monokine milieu induced during the early proinflammatory response to infection and by the subset of NK cells present at the site of inflammation.

CD56 Antigen↗
PubMed1999

Subcutaneous fat in the fetal abdomen as a predictor of growth restriction.

OBJECTIVE: To determine if measuring fetal abdominal fat antenatally using ultrasound can predict fetal growth restriction (FGR). METHODS: One hundred thirty-seven unselected women with singleton pregnancies had serial ultrasound scans at 20, 26, 31, and 38 weeks' gestation. Subcutaneous fat in the fetal abdomen was measured using the same section as the abdominal circumference (AC). Outcome measures were birth weight, neonatal morbidity, and ponderal index. RESULTS: Infants with subcutaneous fat less than 5 mm at 38 weeks (n = 51) were almost five times more likely to have a birth weight below the 10th centile than those with subcutaneous fat of 5 mm or more (n = 75). The incidence of neonatal morbidity was significantly higher in infants with subcutaneous fat less than 5 mm, compared with those with subcutaneous fat of 5 mm or more (20% versus 8%, P < .05). Decreased subcutaneous fat was also associated with a high prevalence of low ponderal index, regardless of birth weight category. CONCLUSION: Measurement of fat in the abdominal wall is a simple technique with a sensitivity for predicting low birth weight similar to that of conventional sonography and might potentially predict FGR irrespective of fetal weight.

Abdomen↗