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A Duggan

Publications and source records attributed to A Duggan.

At least 37 records · Page 2Linked to original sources
PubMed1999

Communicating about youth's sun exposure risk to soccer coaches and parents: a pilot study in Georgia.

Efforts to increase the sun-protective behaviors of children were extended to outdoor recreational sports and youth soccer settings in this study. The pretest results of a pilot survey of coaches (n = 12), parents (n = 50), and youths (n = 61) on eight soccer teams in south Georgia were used to guide the development of a health education program for coaches. In the pilot programs, half the coaches were trained to be involved in soccer-playing youths' sun protection by acting as positive role models and promoting sun protection to youths and their parents. The pilot demonstrated coaches' willingness to participate in sun protection promotion to youth: Youths indicated that coaches and parents were more likely to tell youths to wear sunscreen after the training than before, and coaches perceived getting youths to wear sunscreen to be less difficult than before.

Adolescent↗
PubMed1998

Validation of serum transthyretin (prealbumin) as a nutritional parameter in hemodialysis patients.

OBJECTIVE: To evaluate the use of serum transthyretin (TTR) as a valid indicator of nutritional status in the hemodialysis patient and to validate the correlation of low-serum (TTR) levels with established nutrition assessment parameters. DESIGN: Prospective, cohort, correlation analysis. SETTING: Free-standing outpatient dialysis center. PATIENTS: Fifty-one stable, chronic hemodialysis patients meeting the following selection criteria: (1) received thrice weekly hemodialysis treatments for greater than 3 months, (2) absence of impaired hepatic function, (3) absence of chronic infection, inflammatory syndromes, or infections in the 3 months before the study, (4) not taking corticosteroids, and (5) willing to participate in the study as evidenced by signing of an informed consent. INTERVENTION: Serum TTR, albumin, blood urea nitrogen, creatinine, cholesterol, postdialysis weight and body mass index were measured monthly for 6 consecutive months. Normalized protein catabolic rate and KT/V were measured monthly for 3 consecutive months. MAIN OUTCOME MEASURES: Nutrition and biochemical indices. RESULTS: The overall mean TTR level was 32 mg/dL +/- 7 for the 6-month study period. Thirty-six percent of patients had mean TTR levels less than 30 mg/dL. TTR levels less than 30 mg/dL correlated significantly with urine outputs greater than 240 mL/24 hours, predialysis blood urea nitrogen < 18 mmol/L (<50 mg/dL), and normalized protein catabolic rate less than 0.8 g/kg/d (P < .05). A significant correlation was found between TTR and creatinine, albumin and loss of dry body weight (P < .05). Mean TTR levels less than 30 mg/dL were found in 33% of subjects with mean albumin levels greater than 35 g/L (>3.5 g/dL) and in 19% with mean albumin levels greater than 40 g/L (>4.0 g/dL). TTR levels were consistently lower in diabetics for all 6 months (statistically significant in 2 out of 6 months). CONCLUSION: Measuring serial serum TTR levels in hemodialysis patients is a reliable method for identifying patients in need of nutrition intervention.

Adolescent↗
PubMed1998

Mortality and rebleeding following Transjugular Intrahepatic Portosystemic Stent Shunt for variceal haemorrhage.

The present study investigates clinical factors associated with decreased survival following Transjugular Intrahepatic Portosystemic Stent Shunt (TIPSS). Sixty-seven patients underwent TIPSS for bleeding related to portal hypertension, 42 (63%) on an urgent basis. TIPSS was successfully placed in 65 (97%) patients with no fatal procedural complications. Thirty day mortality was 21%, there being several predictive factors: transfer from another institution, urgency of procedure, sepsis, encephalopathy, higher mean serum bilirubin and low serum albumin. However, using regression analysis, 30 day mortality was predicted independently only by severe liver disease (Child-Pugh C, P= 0.003) and older age (P= 0.003). When stratified by Child-Pugh class, cumulative survival rates at 1 year for class A, B and C were 100, 90 and 34%, respectively. Only three of 25 patient deaths were due to variceal rebleeding. Thirty (46%) patients had a total of 41 rebleeding episodes, with mean time to first rebleed of 4.8 months (range, 3 days-38 months). Cumulative rebleeding rate at 1 year was 25%. Log-rank analysis did not reveal a significant difference in overall survival between rebleeders and non-rebleeders (P= 0.125). When investigated, shunt abnormalities (stenosis, occlusion) were identified in all cases of rebleeding. Our findings confirm TIPSS can be safe and effective in the control of refractory variceal haemorrhage. However, prognosis remains poor for patients with advanced liver disease, particularly if older and in the emergency setting. Vigilant surveillance and high rate of intervention is necessary to maintain shunt patency. Consideration could be given to elective shunt surgery instead of TIPSS for patients with recurrent bleeding and good prognosis liver disease.

Esophageal and Gastric Varices↗
PubMed1998

Regulation of touch receptor differentiation by the Caenorhabditis elegans mec-3 and unc-86 genes.

The nematode Caenorhabditis elegans possesses six morphologically similar neurons that are responsible for sensing gentle touch to the body. Previous genetic studies identified genes that are necessary for the production and differentiation of these touch cells. In particular, unc-86 encodes a POU-type homeodomain protein needed for the production of the touch cells, while mec-3 encodes a LIM-type homeodomain protein needed for the differentiation of the touch cells. Molecular studies showed that MEC-3 and UNC-86 bind cooperatively to sites in the mec-3 promoter and can synergistically activate transcription from it in vitro. Here we show that UNC-86::MEC-3 hetero-oligomer-binding sites are also found in the promoters of two presumed targets of mec-3, the mec-4 and mec-7 genes, that are necessary for the function of the touch cells. These sites, which are well-conserved in the related nematode C. briggsae, are required for promoter activity. When one of the binding sites is cloned into a heterologous promoter, expression is found in the touch cells and two to four other cells that express mec-3 and unc-86. These data support a model in which touch-cell differentiation is specified, in part, by the UNC-86::MEC-3 hetero-oligomer and not by MEC-3 alone. Ectopic expression of mec-3, driven by a heat-shock promoter, also supports this hypothesis: the acquisition of touch-cell characteristics by several additional cells under these conditions required unc-86. Since the touch-cell lineages express UNC-86 before MEC-3, MEC-3 appears to modify the activity of UNC-86, leading to touch-cell-specific gene expression. Because both UNC-86 and MEC-3 have activation domains, the formation of the hetero-oligomer may create a strong activator. In the modification of UNC-86 function by MEC-3 in the touch cells, these studies provide an example of how the sequential activation of transcription factors can determine cell fate within particular cell lineages.

Animals↗
PubMed1998

Evaluation of vaginal infections in adolescent women: can it be done without a speculum?

OBJECTIVE: Given that highly sensitive urine-based nucleic acid amplification tests may eliminate the need for speculum exam to diagnose gonorrhea and chlamydia cervicitis, we sought to determine if vaginal infections could be diagnosed without using a speculum. METHODS: Matched pairs of vaginal specimens were collected from participants before and during speculum exam for diagnosis of trichomoniasis, bacterial vaginosis, and vulvovaginal candidiasis. Females age 12 to 22 years presenting to the Johns Hopkins adolescent primary care clinics who required a pelvic examination were eligible to participate. A convenience sample of 686 patients was recruited between July 1995 and August 1996. Paired vaginal specimens were evaluated with blinded microscopic evaluation. Analysis consisted of: 1) comparison of collection method sensitivities; and 2) assessment of proportions of infections detected by one method that were also detected by the other method. RESULTS: Sensitivities of speculum and nonspeculum collection methods were 75% and 77% (difference = -2%; 95% confidence interval, -11%, 7%) for trichomoniasis, 64% and 68% (difference = -4% [-10%, 3%]) for bacterial vaginosis, and 85% and 80% (difference = 5% [-12%, 22%]) for vulvovaginal candidiasis. The speculum method identified 88% (trichomoniasis), 90% (bacterial vaginosis), and 81% (vulvovaginal candidiasis) of infections detected by the nonspeculum method. The nonspeculum method identified 91% (trichomoniasis), 95% (bacterial vaginosis), and 76% (vulvovaginal candidiasis) of infections detected by the speculum method. CONCLUSIONS: Vaginal infections can be adequately diagnosed without a speculum. Once urine-based diagnosis of gonorrhea and chlamydia becomes well established, it may be possible to perform evaluations for uncomplicated genitourinary complaints without using a speculum.

Adolescent↗
PubMed1998

Diagnosis of Helicobacter pylori in Britain.

The prevalence of Helicobacter pylori infection in the United Kingdom (UK) is similar to that of other developed Western countries with H. pylori infection a major cause of morbidity from peptic ulcer disease and gastric cancer. Guidelines for testing and treating H. pylori have been published and recommend eradicating H. pylori infection in all patients with peptic ulcer disease. With the increasing efficacy and tolerability of H. pylori treatment and the development of near patient tests there is considerable demand for H. pylori testing for screening as well as pre- and post-treatment. In the future this may change the current pattern of testing towards increased population-based non-invasive testing. Currently most investigation for H. pylori occurs within and is funded by the government health-care system. As no one test is suited to all clinical situations, numerous tests for detecting H. pylori are available; however, growing concern about an increasing endoscopy workload has led to the development of screening protocols for endoscopy based on H. pylori status. In the future, the role of H. pylori testing in the management of dyspepsia may also change based on the results of decision analysis models and community-based trials which are currently being performed in the UK.

Decision Support Techniques↗
PubMed1997

The WNB.

Explore the source record for details and available documents.

Humans↗
PubMed1996

The effects of basic training on aerobic fitness and muscular strength and endurance of British Army recruits.

Sixty-two Adult Artillery Recruits, 95 Junior Infantry Soldier Recruits and 104 Junior Infantry Leader Recruits were studied before and after 3, 5 and 11 months, respectively, of British Army basic training. Before basic training the mean maximal oxygen uptake predicted from cycle ergometry (pred VO2max) for Adult Artillery Recruits was 56.1 ml (kg min)-1. It was 58.3 ml (kg min)-1 for the Junior Infantry Soldier Recruits and 58.0 ml (kg min)-1 for the Junior Infantry Leader Recruits. For Adult Artillery Recruits, after basic training there were statistically significant increases in body weight (+2.1%) and pred VO2max (+3.6%) but mixed responses for muscular strength, endurance and fatigue. For Junior Infantry Soldier Recruits, there was no significant change in body weight but a significant reduction in pred VO2max (-2.4%) and a trend towards increased isometric muscular strength. For Junior Infantry Leader Recruits, there were significant increases in body weight (+4.9%), pred VO2max (+3.0%), and isometric muscular strength. These results suggest that the intensity and nature of 3 months of basic training for Adult Artillery Recruits was sufficient to improve their aerobic fitness but was not effective in materially improving muscular strength and endurance. The intensity and nature of basic training for Junior Infantry Soldier Recruits over 5 months was effective in increasing muscular strength but resulted in a decrease in aerobic fitness possibly on account of their high initial fitness level. Basic training over 11 months for Junior Infantry Leader recruits was effective in increasing body weight, aerobic fitness and muscular strength. This may have reflected a change in the intensity and nature of training and in lifestyle after the initial 5 months of basic training, which was undertaken in common with the Junior Infantry Soldier Recruits, or it may be related to normal ageing.

Adolescent↗
PubMed1995

Control of neuronal development in Caenorhabditis elegans.

Recent research into the development of the nervous system of the nematode Caenorhabditis elegans indicates the importance of multiple cell interactions and combinatorial gene expression. As many of the genes needed for C. elegans neuronal development have counterparts with similar activities in Drosophila melanogaster, the mechanisms of cell specification may be broadly conserved.

Animals↗
PubMed1994

Transjugular intrahepatic portosystemic stent-shunt (TIPSS) for variceal haemorrhage: initial results in 28 patients.

BACKGROUND: Endoscopic sclerotherapy is an effective form of treatment of bleeding varices in patients with cirrhosis. However, the mortality in patients who rebleed is high. Recently, transjugular intrahepatic portosystemic stent-shunt (TIPSS) has been developed as an alternative to surgical shunt formation in patients who have failed sclerotherapy. AIM: To review the early experience with TIPSS at a teaching hospital. METHODS: Twenty-eight patients underwent TIPSS on 30 occasions between September 1991 and June 1993 for bleeding oesophageal or gastric varices. The majority had alcoholic liver disease. RESULTS: TIPSS was performed successfully in all patients. Immediate control of bleeding was achieved, but one patient rebled within 24 hours. Complications related to the procedure occurred in 30%, but no patient died from these. Thirty-day mortality was 11% (three of 28), two patients dying from progressive liver failure and one from sepsis. A further three patients died from six weeks to two months following TIPSS, due to liver failure in one, spontaneous bacterial peritonitis in the second and in the third after a fall. This represents an overall mortality of 21%. Three patients have rebled at mean follow-up of 11.3 months. One of these had repeat TIPSS while the other two had balloon dilatation of the stent with control of bleeding. Four patients developed mild chronic encephalopathy which was readily controlled with medical therapy. CONCLUSIONS: TIPSS is an effective means for control of bleeding from oesophageal and/or gastric varices not responding to other methods. Further follow-up is required with regard to rates of rebleeding, encephalopathy and survival.

Adult↗
PubMed1992

Prediction of the metabolic cost of walking with and without loads.

Measurement of the metabolic cost of walking inconveniences subjects, and requires skilled technical support and expensive equipment. These factors have stimulated interest in predictive equations. The present study assessed existing equations. Under each of 17 combinations of gradient (0-6%) and carried load (4.1-37.4 kg), 7-12 men undertook treadmill walking at 1.67 m/s. Measured oxygen consumption and respiratory exchange ratio were used to calculate metabolic rate (MRobserved). Metabolic rate was also predicted from the equation of Pandolf et al. (1977) (MRpandolf) and, where appropriate, from another five equations relating to walking without loads. MRobserved and MRpandolf did not differ significantly (p greater than 0.05) under any combination of gradient and load. The overall mean MRobserved and MRpandolf of 609 W and 602 W, respectively, also did not differ significantly (p greater than 0.05). These variables were highly correlated (r = 0.94) with a standard deviation about the prediction error of 47 W. For level walking without loads, the mean predictions from the equations of Pandolf et al. (1977) and Cotes and Meade (1960) did not differ significantly (p greater than 0.05) from the mean MRobserved of 428 Watts, but four other equations overestimated by 17-74 W. In conclusion, the Pandolf et al. (1977) equation has given good results across the range of combinations of load and gradient tested, and the errors are considered acceptable for most practical purposes.

Adult↗
PubMed1990

Hairy cell leukemia-associated antigen (HC2) is an activation antigen of several hemopoietic cell lineages, inducible on monocytes by IFN-gamma.

The HC2 Ag is defined by a mAb raised against leukemic B lymphocytes from a patient with hairy cell leukemia (HCL). This 60 to 70-kDa Ag was immunoprecipitated from EBV-transformed B lymphoblastoid cell lines, from HCL-B cells, from the HUT-102 T cell line infected with HTLVI, and from activated monocytes. A binding assay with radioiodinated Fab' anti-HC2 confirmed this cellular distribution of the Ag and demonstrated 500 to 3000 binding sites on resting T cells, 300 to 11,000 binding sites on non-T cells, less than 3000 binding sites on chronic lymphocytic leukemia B cells, and 29,000 to 223,000 binding sites on HCL-B cells. PMA plus anti-CD3 up-regulated HC2 expression on T cells and IFN-gamma up-regulated expression on monocytes. On B cells, EBV transformation may result in HC2 expression, and antibody to HC2 has been found to inhibit B cell differentiation and proliferation. The combined results suggest an important role for the HC2 membrane-associated Ag on cells responsible for the immune response.

Antibodies, Monoclonal↗
PubMed1990

Blood lactate at 12 km/h and vOBLA as predictors of run performance in non-endurance athletes.

Run velocity at the onset of blood lactate accumulation (vOBLA) has been reported to be highly correlated with performance in endurance runs. From capillary blood samples taken during incremental treadmill running, vOBLA and the blood lactate concentration at a run speed of 12 km/h (La12) were determined in a group of 11 men which excluded endurance athletes. The inter-relationships between these variables, 4-km run performance and maximal oxygen uptake (VO2max) were investigated. vOBLA and La12 were highly correlated with one another (r = -0.95). Mean 4-km run speed was found to be closely related to vOBLA (r = 0.86), La12 (r = -0.88) and VO2max (r = 0.86). Reproducibility of both vOBLA and La12 was found to be good; test and re-test scores were highly correlated (r greater than or equal to 0.93) and did not differ significantly (p greater than 0.05). The present study suggests that vOBLA may be a valid and reproducible predictor of run performance in individuals who are not endurance athletes. It was not, however, found to be better in these respects than La12, the measurement of which would be easier and less traumatic to the subject since it would require less blood sampling.

Adult↗