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Other Published Studies (other + published_studies)

Distribution by Scientific Domains

Life Sciences	53%
Medical Sciences	40%

Selected Abstracts

Effect of experimentally altered food abundance on fat reserves of wintering birds

JOURNAL OF ANIMAL ECOLOGY, Issue 5 2003
Christopher M. Rogers
Summary 1Current models of adaptive fat regulation make opposing predictions concerning the effect of increased winter food supply on size of the avian winter fat reserve. To distinguish between models, food supply was varied experimentally in nature and two measures of size of the fat reserve were taken at food-supplemented sites and non-supplemented sites. 2In two winters, most of the seven species sampled showed slightly higher visible subcutaneous fat class at supplemented than at non-supplemented sites; treatment and species factors were statistically significant. Body mass corrected for wing length showed a similar if non-significant trend. 3A parallel dispersal study of birds colour-banded at non-supplemented sites showed that these birds did not move 0·8 or 1·5 km to use supplemental food at private feeding stations in the study areas. In addition, accipiter hawk attack rate did not differ between supplemented and non-supplemented sites. 4These results are consistent with a model of adaptive fat regulation (based on between-day environmental variability caused by severe weather events) that predicts an increase in the winter fat reserve at increased food supply. Other published studies, all from the north temperate zone, showed the same pattern. 5The present results are inconsistent with a second model (based on within-day foraging interruption) which predicts a decrease in the fat reserve under increased food supply. However, a set of published studies, all from tropical regions or regions with mild maritime climate, showed the decrease at higher food predicted by the second but not the first model. 6Models of adaptive fat regulation in small birds are therefore limited in their predictive power, perhaps because they are developed for environments that differ in the time scale of environmental stochasticity. New studies are needed that explore further the complexities of environment-specific adaptive fat models, e.g. a winter feeding experiment in a tropical bird species. [source]

The ,apparent clearance' of free phenytoin in elderly vs. younger adults

BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 1 2010
Daniel F. B. Wright
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT , The clearance of many drugs is reduced in the elderly, but the data regarding phenytoin are conflicting. Most studies have estimated phenytoin metabolic clearance using total drug concentrations (bound plus unbound), which may be confounded by protein binding effects. Free phenytoin concentrations are independent of protein binding and should more accurately reflect true metabolic clearance changes in elderly patients. WHAT THIS STUDY ADDS , The two studies reported in this paper suggest a trend towards reduced free phenytoin ,apparent clearance' in the elderly, although statistically significant results were not found. Other published studies have largely found similar trends, suggesting an age effect. AIMS To test the hypothesis that the ,apparent clearance' of free phenytoin is reduced in elderly patients. METHODS Two separate studies were conducted comparing free phenytoin ,apparent clearance' in elderly vs. younger adults. The first study was a retrospective analysis of free phenytoin concentrations measured at Christchurch Hospital from 1997 to 2006. In the second study free phenytoin concentrations were measured prospectively in ambulatory subjects who were taking phenytoin regularly. RESULTS In the retrospective study (n= 29), free phenytoin ,apparent clearance' was 0.27 ± 0.04 l kg,1 day,1 (95% CI 0.19, 0.34) in the elderly cohort vs. 0.37 ± 0.06 l kg,1 day,1 (95% CI 0.22, 0.52) in younger adults, but the difference was not statistically significant. In the prospective study, free phenytoin ,apparent clearance' showed a non-significant trend to being reduced in the elderly patients (0.12 ± 0.02 l kg,1 day,1, 95% CI 0.07, 0.17) compared with the younger cohort (0.18 ± 0.07 l kg,1 day,1, 95% CI 0.09, 0.26) in those not taking interacting drugs (n= 21). CONCLUSIONS This research does not prove the hypothesis that the ,apparent clearance' of free phenytoin is reduced in the elderly. However, the trends found in these two studies are supported by trends in the same direction in other published studies, suggesting an age effect. [source]

Urodynamic findings in children with cerebral palsy

INTERNATIONAL JOURNAL OF UROLOGY, Issue 8 2005
M IHSAN KARAMAN
Abstract Aim: More than one-third of children with cerebral palsy are expected to present with dysfunctional voiding symptoms. The voiding dysfunction symptoms of the cerebral palsy patients in the present study were documented. Methods: Of the study group, 16 were girls and 20 were boys (mean age: 8.2 years). Children with cerebral palsy were evaluated with urodynamics consisting of flow rate, filling and voiding cystometry, and electromyography findings of the external urethral sphincter to determine lower urinary tract functions. Treatment protocols were based on the urodynamic findings. Anticholinergic agents to reduce uninhibited contractions and to increase bladder capacity were used as a treatment. Clean intermittent catheterization and behavioral modification were used for incomplete emptying. Results: Of the children, 24 (66.6%) were found to have dysfunctional voiding symptoms. Daytime urinary incontinence (47.2%) and difficulty urinating (44.4%) were the most common symptoms. Urodynamic findings showed that neurogenic detrusor overactivity (involuntary contractions during bladder filling) with a low bladder capacity was present in 17 (47.2%) children, whereas detrusor,sphincter dyssynergia was present in four patients (11%). The mean bladder capacity of patients with a neurogenic bladder was 52.2% of the expected capacity. Conclusions: The present study concluded that voiding dysfunction was seen in more than half of the children with cerebral palsy, which is a similar result to other published studies. We propose that a rational plan of management of these patients depends on the evaluation of the lower urinary tract dysfunction with urodynamic studies. These children benefit from earlier referral for assessment and treatment. [source]

Estimation of the proportion of body fat in mice from the proportion of body water

JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5-6 2003
A. H. M. Terpstra
Summary We compared the proportion of body fat in mice as measured by chemical analysis with that estimated from the proportion of body water. First, we measured the proportion of fat by chemical analysis in 78 mice that had a proportion of body fat in the range from approximately 5 to 20%. Then, we constructed a regression line that described the relationship between the proportion of body water and the proportion of body fat by using data from several other published studies in mice (% body fat = ,1.20 × % body water + 88.07, r = 0.9597, sy.x = 2.75, p < 0.001). With this regression line, we estimated the proportion of body fat from the proportion of body water that was measured by drying the carcasses at 60 °C for 3 days. Body fat data obtained from this regression line were similar to those obtained by chemical analysis. Thus, these results suggest that reliable values for the proportion of body fat can be derived from the proportion of body water and this method provides a tool to rapidly measure the proportion of body fat in mice. [source]

Participants' Attitudes in the Utah Juvenile Victim-Offender Mediation Program

JUVENILE AND FAMILY COURT JOURNAL, Issue 1 2002
BARTON POULSON PH.D.
ABSTRACT This paper describes an archival evaluation of the Juvenile Court Victim-Offender Mediation Program (VOMP) of the Utah State Courts in Salt Lake City. From 1997 to 2000, 147 victims and 330 offenders reported their attitudes towards their experiences in VOMP. Although victims were more satisfied than offenders for some outcomes, all participants reported exceptionally high satisfaction. These promising results are consistent with other published studies on the effectiveness of VOMP and other forms of restorative justice in demonstrating the promise of mediation in criminal justice. [source]

Data quality in thermal summation development models for forensically important blowflies

MEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2009
C. S. RICHARDS
Abstract. To highlight some issues regarding data quality that are significant in estimating post-mortem intervals (PMI) from maggots, the developmental constants of thermal summation models for development of Chrysomya megacephala Fabricius (Diptera: Calliphoridae) were calculated from incidental data gathered from 12 published studies, and from data generated specifically for the purpose in a single experiment. The focused experiment involved measuring the timing of five developmental landmarks at nine constant temperatures with a sampling resolution of 6,12 h, which is characteristic of other published studies. Combining data from different studies produced inconsistent results because of statistical noise introduced by (at least) disparities in temporal precision, descriptive statistics, geographical location and rearing diets. A robust experimental design to estimate a developmental model should involve at least six constant temperatures, starting at about 7°C above the relevant developmental zero (D0) and going almost to the upper critical temperature, and a temporal sampling interval with a relative precision of about 10%, which requires sampling about every 2 h until hatching, about every 3 h until first ecdysis and about every 6 h until second ecdysis. [source]

Design principles for virtual patients: a focus group study among students

MEDICAL EDUCATION, Issue 6 2009
Sören Huwendiek
Objectives, This study aimed to examine what students perceive as the ideal features of virtual patient (VP) design in order to foster learning with a special focus on clinical reasoning. Methods, A total of 104 Year 5 medical students worked through at least eight VPs representing four different designs during their paediatric clerkship. The VPs were presented in two modes and differed in terms of the authenticity of the user interface (with or without graphics support), predominant question type (long- versus short-menu questions) and freedom of navigation (relatively free versus predetermined). Each mode was presented in a rich and a poor version with regard to the use of different media and questions and explanations explicitly directed at clinical reasoning. Five groups of between four and nine randomly selected students (n = 27) participated in focus group interviews facilitated by a moderator using a questioning route. The interviews were videotaped, transcribed and analysed. Summary reports were approved by the students. Results, Ten principles of VP design emerged from the analysis. A VP should be relevant, of an appropriate level of difficulty, highly interactive, offer specific feedback, make optimal use of media, help students focus on relevant learning points, offer recapitulation of key learning points, provide an authentic web-based interface and student tasks, and contain questions and explanations tailored to the clinical reasoning process. Conclusions, Students perceived the design principles identified as being conducive to their learning. Many of these principles are supported by the results of other published studies. Future studies should address the effects of these principles using quantitative controlled designs. [source]

Extensive spatial genetic structure revealed by AFLP but not SSR molecular markers in the wind-pollinated tree, Fagus sylvatica

MOLECULAR ECOLOGY, Issue 5 2007
ALISTAIR S. JUMP
Abstract Studies of fine-scale spatial genetic structure (SGS) in wind-pollinated trees have shown that SGS is generally weak and extends over relatively short distances (less than 30,40 m) from individual trees. However, recent simulations have shown that detection of SGS is heavily dependent on both the choice of molecular markers and the strategy used to sample the studied population. Published studies may not always have used sufficient markers and/or individuals for the accurate estimation of SGS. To assess the extent of SGS within a population of the wind-pollinated tree Fagus sylvatica, we genotyped 200 trees at six microsatellite or simple sequence repeat (SSR) loci and 250 amplified fragment length polymorphisms (AFLP) and conducted spatial analyses of pairwise kinship coefficients. We re-sampled our data set over individuals and over loci to determine the effect of reducing the sample size and number of loci used for SGS estimation. We found that SGS estimated from AFLP markers extended nearly four times further than has been estimated before using other molecular markers in this species, indicating a persistent effect of restricted gene flow at small spatial scales. However, our SSR-based estimate was in agreement with other published studies. Spatial genetic structure in F. sylvatica and similar wind-pollinated trees may therefore be substantially larger than has been estimated previously. Although 100,150 AFLP loci and 150,200 individuals appear sufficient for adequately estimating SGS in our analysis, 150,200 individuals and six SSR loci may still be too few to provide a good estimation of SGS in this species. [source]

Orientation of specialist and generalist fungivorous ciid beetles to host and non-host odours

PHYSIOLOGICAL ENTOMOLOGY, Issue 3 2000
Roger Guevara
Abstract Most ciids (Ciidae) are strict fungivores specialized on fruit bodies of wood-rotting fungi. The Ciidae includes both specialist and generalist species. Recent evidence suggests that ciids locate and discriminate their potential hosts based mainly on fungal odours. In this study, we investigated the field distribution of ciids in a local woodland near Bath, U.K. We also evaluated experimentally the behavioural responses of ciids to host and non-host fungi in an olfactometer, and explored potential differences in putative aroma compounds in host fungi. Our field data showed that Octotemnus glabriculus, Cis boleti and Cis nitidus have preference for one host species, whereas C. bilamellatus has no preference. The experimental evidence was in accordance with the field observations. The specialists O. glabriculus, C. boleti and C. nitidus were specifically attracted to odour compounds of their preferred host fungi: Coriolus versicolor for the first two beetles and Ganoderma adspersum for the latter one. By contrast, the generalist C. bilamellatus was attracted to odours from C. versicolor, G. adspersum and Piptoporus betulinus. The evidence from this and other published studies suggest that ciids depend mainly on fruit body odours for location and discrimination of their host fungi. In accordance with this, we observed diffierential behavioural responses of ciids to aroma compounds of host and non-host species. [source]

ORIGINAL ARTICLE: Soluble Human Leukocyte Antigen-G Isoforms in Maternal Plasma in Early and Late Pregnancy

AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2009
Roberta Rizzo
Problem Human Leukocyte Antigen (HLA)-G is a class Ib gene located in the human major histocompatibility complex (MHC). Several lines of investigation indicate that the HLA-G molecule is involved in the maternal acceptance of the semi-allogenic fetus during pregnancy and in the development of tolerance. Expression of soluble HLA-G (sHLA-G) is positively correlated with successful in vitro fertilization (IVF) treatments, and aberrant expression of HLA-G in certain complications of pregnancy, such as pre-eclampsia and spontaneous abortion, has been reported. The main purpose of this study was to investigate the levels of different soluble HLA-G isoforms in maternal plasma in early and late pregnancy. Method of study Soluble HLA-G (sHLA-G) can be detected in maternal blood, and in this study, two different isoforms of sHLA-G, namely sHLA-G1 generated by shedding of membrane-bound HLA-G1 and HLA-G generated by specific HLA-G transcripts, have been investigated early [median of 16.4 weeks of gestation (GW)] and late (median: 38.9 GW) in pregnancy in an original cohort of 580 pregnant Caucasian women. Results Lower concentrations of sHLA-G1 were found late in pregnancy (>32 GW) in a group of women with severe pre-eclampsia compared with controls with uncomplicated pregnancies (P = 0.029, PC = 0.09; Mann,Whitney; Logistic regression analysis: P = 0.024, OR = 0.920, 95% CI: 0.855,0.989). However, this was not the case with HLA-G5, and significantly more of the cases with severe pre-eclampsia had detectable plasma HLA-G5 compared with that of the control group (P = 0.013, PC = 0.04; Mann,Whitney). Similar findings were not observed in women with gestational hypertension or existing hypertension continuing into pregnancy. Furthermore, there was a trend toward lower maternal plasma sHLA-G1 in a group of women with premature birth (<37 GW) compared with that of the control group (P = 0.028, PC = 0.17; Mann,Whitney). On the contrary, HLA-G5 was lower in the control group compared with that in the premature group (P = 0.004, PC = 0.02; Mann,Whitney). Conclusion This study shows in line with other published studies that a high, detectable soluble HLA-G concentration in maternal plasma or serum is not mandatory for a successful pregnancy. However, complications during pregnancy, such as (severe) pre-eclampsia, spontaneous abortion, IUGR, and premature birth, are associated with a low or undetectable level of soluble HLA-G in the maternal blood circulation. Also, this study indicates that sHLA-G1 is the interesting soluble HLA-G isoform in pre-eclampsia, and that low or undetectable levels of HLA-G5 at the end of pregnancy seem to be associated with an uncomplicated normal pregnancy, whereas in severe pre-eclampsia and possibly other pregnancy complications, such as preterm birth and IUGR, the level of HLA-G5 is higher. [source]

Identification of single nucleotide polymorphisms in the bovine CCL2, IL8, CCR2 and IL8RA genes and their association with health and production in Canadian Holsteins

ANIMAL GENETICS, Issue 3 2007
I. Leyva-Baca
Summary The aim of this study was to identify the presence of SNPs in the chemokine genes CCL2 and IL8 and the chemokine receptor genes IL8RA and CCR2, and assess their potential contribution to variation in estimated breeding values (EBVs) for somatic cell score (SCS) and four other traits in Canadian Holstein bulls. Pools of DNA for bulls with high (H) and low (L) EBVs for SCS were used for identification of 11 SNPs. Two unreported SNPs were found in the CCL2 gene and one SNP was found in the CCR2 gene. Previously reported SNPs (three in the IL8 gene and five in the IL8RA chemokine receptor) were also identified. Two SNPs in CCL2, three in IL8, one in IL8RA and one in CCR2 were genotyped in Canadian Holstein bulls (n = 338) using tetra primer ARMS-PCR. We investigated associations of these seven polymorphisms with three production traits (milk yield, fat yield and protein yield) and one conformation trait related to mastitis (udder depth). The allele substitution effect for the CCL2 rs41255713:T>C SNP was significant at an experimental-wise level for milk yield (247.5 ± 79.9 kg) and protein yield (7.4 ± 2.3 kg) EBVs (P , 0.05). The associations of the SNPs with SCS EBVs were not significant at an experimental-wise level. However, the allele substitution effect of the CCR2 rs41257559:C>T SNP on SCS was significant at the comparison-wise level (,0.04 ± 0.02, P = 0.05), which might indicate a possible association in support of other published studies. Lastly, we assigned CCR2 to BTA22q24, where a previously QTL for SCS was identified. [source]

Continuous wave and simulated GSM exposure at 1.8 W/kg and 1.8 GHz do not induce hsp16-1 heat-shock gene expression in Caenorhabditis elegans

BIOELECTROMAGNETICS, Issue 2 2008
Adam S. Dawe
Abstract Recent data suggest that there might be a subtle thermal explanation for the apparent induction by radiofrequency (RF) radiation of transgene expression from a small heat-shock protein (hsp16-1) promoter in the nematode, Caenorhabditis elegans. The RF fields used in the C. elegans study were much weaker (SAR 5,40 mW,kg,1) than those routinely tested in many other published studies (SAR ,2 W,kg,1). To resolve this disparity, we have exposed the same transgenic hsp16-1::lacZ strain of C. elegans (PC72) to higher intensity RF fields (1.8 GHz; SAR ,1.8 W,kg,1). For both continuous wave (CW) and Talk-pulsed RF exposures (2.5 h at 25 °C), there was no indication that RF exposure could induce reporter expression above sham control levels. Thus, at much higher induced RF field strength (close to the maximum permitted exposure from a mobile telephone handset), this particular nematode heat-shock gene is not up-regulated. However, under conditions where background reporter expression was moderately elevated in the sham controls (perhaps as a result of some unknown co-stressor), we found some evidence that reporter expression may be reduced by ,15% following exposure to either Talk-pulsed or CW RF fields. Bioelectromagnetics 29:92,99, 2008. © 2007 Wiley-Liss, Inc. [source]

Pharmacokinetics of nifedipine in Taiwanese

BIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 2 2004
Shu-Chen Chien
Abstract To elucidate the pharmacokinetics of nifedipine in Taiwanese, a retrospective review of nifedipine bioequivalence studies completed in Taiwan in the past 5 years was conducted. A total of 198 healthy male volunteers were given a single dose of a 10 mg Adalat® capsule as a reference drug after overnight fasting. Pharmacokinetic parameters derived from Adalat® administration were calculated by non-compartmental analysis with the WinNonlin program. After oral administration of an immediate-release dosage form of a 10 mg nifedipine capsule to Taiwan residents, a skewed distribution with no clear evidence of bimodality of pharmacokinetic parameters was observed. The mean Cmax was 143.12±53.48 ng/ml, the mean AUC was 293.77±115.62 ng·h/ml, the mean T1/2 was 3.08±1.61 h, and the median value of Tmax was 0.61 h. Compared with other published studies, the Cmax and AUC of nifedipine after 10 mg administration were significantly higher in Taiwanese than in British and American subjects. However, the Cmax and AUC were similar to those of Indian and Mexican subjects. According to the antimode of AUC distribution of 22.5 ng·h/ml/mg proposed by Kleinbloesem, 69.7% of Taiwanese can be categorized as slow metabolizers. Based on the results in this study, the majority of Taiwanese show lower activity of nifedipine metabolism. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Optimization of an enrichment process for circulating tumor cells from the blood of head and neck cancer patients through depletion of normal cells

BIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009
Liying Yang
Abstract The optimization of a purely negative depletion, enrichment process for circulating tumor cells (CTCs) in the peripheral blood of head and neck cancer patients is presented. The enrichment process uses a red cell lysis step followed by immunomagnetic labeling, and subsequent depletion, of CD45 positive cells. A number of relevant variables are quantified, or attempted to be quantified, which control the performance of the enrichment process. Six different immunomagnetic labeling combinations were evaluated as well as the significant difference in performance with respect to the blood source: buffy coats purchased from the Red Cross, fresh, peripheral blood from normal donors, and fresh peripheral blood from human cancer patients. After optimization, the process is able to reduce the number of normal blood cells in a cancer patient's blood from 4.05,×,109 to 8.04,×,103 cells/mL and still recover, on average, 2.32 CTC per mL of blood. For all of the cancer patient blood samples tested in which CTC were detected (20 out of 26 patients) the average recovery of CTCs was 21.7 per mL of blood, with a range of 282 to 0.53 CTC. Since the initial number of CTC in a patient's blood is unknown, and most probably varies from patient to patient, the recovery of the CTC is unknown. However, spiking studies of a cancer cell line into normal blood, and subsequent enrichment using the optimized protocol indicated an average recovery of approximately 83%. Unlike a majority of other published studies, this study focused on quantifying as many factors as possible to facilitate both the optimization of the process as well as provide information for current and future performance comparisons. The authors are not aware any other reported study which has achieved the performance reported here (a 5.66 log10) in a purely negative enrichment mode of operation. Such a mode of operation of an enrichment process provides significant flexibility in that it has no bias with respect to what attributes define a CTC; thereby allowing the researcher or clinician to use any maker they choose to define whether the final, enrich product contains CTCs or other cell type relevant to the specific question (i.e., does the CTC have predominately epithelial or mesenchymal characteristics?). Biotechnol. Bioeng. 2009;102: 521,534. © 2008 Wiley Periodicals, Inc. [source]