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PubMed2006

UMTS base station-like exposure, well-being, and cognitive performance.

BACKGROUND: Radio-frequency electromagnetic fields (RF EMF) of mobile communication systems are widespread in the living environment, yet their effects on humans are uncertain despite a growing body of literature. OBJECTIVES: We investigated the influence of a Universal Mobile Telecommunications System (UMTS) base station-like signal on well-being and cognitive performance in subjects with and without self-reported sensitivity to RF EMF. METHODS: We performed a controlled exposure experiment (45 min at an electric field strength of 0, 1, or 10 V/m, incident with a polarization of 45 degrees from the left back side of the subject, weekly intervals) in a randomized, double-blind crossover design. A total of 117 healthy subjects (33 self-reported sensitive, 84 nonsensitive subjects) participated in the study. We assessed well-being, perceived field strength, and cognitive performance with questionnaires and cognitive tasks and conducted statistical analyses using linear mixed models. Organ-specific and brain tissue-specific dosimetry including uncertainty and variation analysis was performed. RESULTS: In both groups, well-being and perceived field strength were not associated with actual exposure levels. We observed no consistent condition-induced changes in cognitive performance except for two marginal effects. At 10 V/m we observed a slight effect on speed in one of six tasks in the sensitive subjects and an effect on accuracy in another task in nonsensitive subjects. Both effects disappeared after multiple end point adjustment. CONCLUSIONS: In contrast to a recent Dutch study, we could not confirm a short-term effect of UMTS base station-like exposure on well-being. The reported effects on brain functioning were marginal and may have occurred by chance. Peak spatial absorption in brain tissue was considerably smaller than during use of a mobile phone. No conclusions can be drawn regarding short-term effects of cell phone exposure or the effects of long-term base station-like exposure on human health.

Adult↗

PubMed2006

Observation of children with attention-deficit hyperactivity (ADHD) problems in three natural classroom contexts.

BACKGROUND: Observation studies of students with attention-deficit hyperactivity disorder (ADHD) problems in natural classroom situations are costly and relatively rare. AIMS: The study enquired how teacher ratings are anchored in actual student classroom behaviours, and how the behaviour of children with ADHD problems differs from their classmates. The authors attempted to broaden the usual focus on disruptive and inattentive behaviours to elucidate the role of various on-task behaviours, as well as considering differences between classroom contexts. SAMPLE: DSM-III-R criteria were used in conjunction with a teacher rating scale to select a sample of 55 students with ADHD problems, and 55 matched controls from a population of 569 primary school students. METHOD: Students were observed in their natural classrooms using the Munich Observation of Attention Inventory (MAI; Helmke, 1988). Correlations between teacher reports and observation codes were computed, and systematic differences between students with ADHD problems and controls in different classroom contexts were examined using a generalized linear mixed model (GLMM). RESULTS: Global teacher reports showed moderate to strong correlations with observed student behaviours. Expected on-task behaviour demonstrated the strongest relationship (r>-.70) with teacher reports. As hypothesized, the children with ADHD were more disruptive and inattentive than their matched peers. They were also less often inconspicuous on-task as expected by their teachers. However, their behaviour was assigned to two other on-task categories more often than their peers, and this raised their total on-task behaviour to over 66%. Situational differences were found for all codes as well, which mostly affected all students in a similar way, not just students with ADHD. CONCLUSIONS: ADHD related behaviours are pervasive across the classroom situations coded. Teachers appear to distinguish between desirable and undesirable on-task behaviours. Nevertheless, assisting students with ADHD problems requires shaping both. Future studies need to include more differentiated codes for various types of on-task behaviours and also need to code the lesson context concurrently.

Attention Deficit Disorder with Hyperactivity↗

PubMed2006

Generalized reliability estimation using repeated measurements.

Reliability can be studied in a generalized way using repeated measurements. Linear mixed models are used to derive generalized test-retest reliability measures. The method allows for repeated measures with a different mean structure due to correction for covariate effects. Furthermore, different variance-covariance structures between measurements can be implemented. When the variance structure reduces to a random intercept (compound symmetry), classical methods are recovered. With more complex variance structures (e.g. including random slopes of time and/or serial correlation), time-dependent reliability functions are obtained. The effect of time lag between measurements on reliability estimates can be evaluated. The methodology is applied to a psychiatric scale for schizophrenia.

Humans↗

PubMedDate not supplied

RCT of a care manager intervention for major depression in primary care: 2-year costs for patients with physical vs psychological complaints.

PURPOSE: Depression care management for primary care patients results in sustained improvement in clinical outcomes with diminishing costs over time. Clinical benefits, however, are concentrated primarily in patients who report to their primary care clinicians psychological rather than exclusively physical symptoms. This study proposes to determine whether the intervention affects outpatient costs differentially when comparing patients who have psychological with patients who have physical complaints. METHODS: We undertook a group-randomized controlled trial (RCT) of depression comparing intervention with usual care in 12 primary care practices. Intervention practices encouraged depressed patients to engage in active treatment, using nurses to provide regularly scheduled care management for 24 months. The study sample included 200 adults beginning a new depression treatment episode where patient presentation style could be identified. Outpatient costs were defined as intervention plus outpatient treatment costs for the 2 years. Cost-offset analysis used general linear mixed models, 2-part models, and bootstrapping to test hypotheses regarding a differential intervention effect by patients' style, and to obtain 95% confidence intervals for costs. RESULTS: Intervention effects on outpatient costs over time differed by patient style (P <.05), resulting in a $980 cost decrease for depressed patients who complain of psychological symptoms and a 1,378 dollars cost increase for depressed patients who complain of physical symptoms only. CONCLUSIONS: Depression intervention for a 2-year period produced observable clinical benefit with decreased outpatient costs for depressed patients who complain of psychological symptoms. It produced limited clinical benefit with increased costs, however, for depressed patients who complain exclusively of physical symptoms, suggesting the need for developing new intervention approaches for this group.

Adult↗

PubMed2025

Predicting and comparing transcription start sites in single cell populations.

The advent of 5' single-cell RNA sequencing (scRNA-seq) technologies offers unique opportunities to identify and analyze transcription start sites (TSSs) at a single-cell resolution. These technologies have the potential to uncover the complexities of transcription initiation and alternative TSS usage across different cell types and conditions. Despite the emergence of computational methods designed to analyze 5' RNA sequencing data, current methods often lack comparative evaluations in single-cell contexts and are predominantly tailored for paired-end data, neglecting the potential of single-end data. This study introduces scTSS, a computational pipeline developed to bridge this gap by accommodating both paired-end and single-end 5' scRNA-seq data. scTSS enables joint analysis of multiple single-cell samples, starting with TSS cluster prediction and quantification, followed by differential TSS usage analysis. It employs a Binomial generalized linear mixed model to accurately and efficiently detect differential TSS usage. We demonstrate the utility of scTSS through its application in analyzing transcriptional initiation from single-cell data of two distinct diseases. The results illustrate scTSS's ability to discern alternative TSS usage between different cell types or biological conditions and to identify cell subpopulations characterized by unique TSS-level expression profiles.

Transcription Initiation Site↗

PubMed2026

Assessing the accuracy and efficiency of an electronic platform for managing childhood illnesses in rural China: A cluster randomized controlled trial.

OBJECTIVES: The Integrated Management of Childhood Illness (IMCI) faces challenges in capacity building and quality control. This trial aims to assess an electronic IMCI (eIMCI) platform in improving the effectiveness and efficiency in disease classification and management by community health workers (CHWs). DESIGN: Cluster randomized controlled trial. SETTING: Rural western China. PARTICIPANTS: 24 CHWs and 72 ill children aged 2 months to 5 years (3 children per CHW). CHWs were randomly assigned to intervention or control groups. INTERVENTIONS: The intervention CHWs received online training and performed disease management using the eIMCI platform featuring integrated training modules and decision-support tools. The control group received traditional face-to-face training and used paper-based IMCI protocols. MAIN OUTCOME MEASURES: Proportion of children correctly diagnosed or classified by CHWs, as determined by a pediatric specialist. Relative risk (RR) between groups was estimated using Poisson Generalized Linear Mixed Models incorporating a random intercept for CHW to account for clustering of children within individual CHWs and adjusting for key covariates at both the CHW and child levels. RESULTS: The intervention group (13 CHWs, 39 children) had a higher rate of correct classification (64.1%) compared to the control group (11 CHWs, 33 children) (39.4%, P = .056). Multivariable regression analysis confirmed this (RR = 2.1, 95% CI: 1.5-3.1; P < .001). No significant difference was found in correct treatment rates (38.5% vs. 27.3%, P = .316). Online training reduced time and costs by approximately 80%, though with a slight decrease in post-training evaluation scores. CONCLUSIONS: The eIMCI platform shows potential in enhancing IMCI implementation and significantly reducing the training burden in resource-limited settings. Trial registration: Chinese Clinical Trial Registry: ChiCTR2100042533, https://www.chictr.org.cn/showproj.html?proj=119995.

Humans↗

PubMed2001

Birthweight and body mass index in young adulthood: the Swedish young male twins study.

Many studies have found an inverse association between fetal growth and cardiovascular disease related to the metabolic syndrome in adulthood. Nevertheless, the relative importance of genetics and the intrauterine environment remain unclear. The objective of the study was to test the fetal origins hypothesis and the fetal insulin resistance hypothesis by studying the impact of fetal growth on Body Mass Index (BMI) in young adulthood. In a nationwide cohort study, the Swedish Medical Birth Register for the years 1973-1979 was linked with the Military Service Conscription Register for 1990-1999. In 1998 a questionnaire was mailed to all male twins, included in the two registers, who were alive and still resident in Sweden. The study covers the 923 male twin pairs for which full data were available. Mixed linear models were used to estimate within-pair and between-pair differences in birthweight and their relations to BMI. A weak positive association was found among the monozygotic twins for the withinpair difference in birthweight and BMI. No significant association was found among the monozygotic for the between-pair difference in birthweight and BMI. No significant associations were found for dizygotic twins. These findings do not seem to support either the fetal programming hypothesis or the fetal insulin resistance hypothesis.

Adult↗

PubMed2005

A pilot study of the effect of inhaled buffered reduced glutathione on the clinical status of patients with cystic fibrosis.

STUDY OBJECTIVES: To assess the impact of inhaled, buffered reduced glutathione (GSH) on clinical indicators of cystic fibrosis (CF) pathophysiology. DESIGN AND PATIENTS: A randomized, double-blind, placebo-controlled pilot study was conducted over an 8-week period. Nineteen subjects, age 6 to 19 years, with CF status documented by positive sweat chloride test results (> 60 mEq/L) were recruited for the trial. After matching on age and sex, 10 patients were randomly assigned to the treatment group and 9 patients to the placebo group. Primary outcomes were FEV1, FVC, forced expiratory flow at 25 to 75% of vital capacity, and peak flow; secondary outcomes were body mass index, 6-min walk distance, and self-reported cough frequency, mucus production/viscosity/color, wellness, improvement, and stamina. INTERVENTIONS AND ANALYSIS: Treatment was buffered GSH, and placebo was sodium chloride with a hint of quinine. The total daily dose of buffered GSH was approximately 66 mg/kg of body weight, and the total daily dose of placebo was approximately 15 mg/kg of body weight (quinine, 25 to 30 microg/kg). Doses were distributed across four inhalation sessions per day and spaced 3- to 4-h apart. General linear mixed models were used to analyze the data. The final sample size was nine subjects in the treatment group and seven subjects in the placebo group. RESULTS: Mean change for peak flow was -6.5 L/min for the placebo group and +33.7 L/min for the GSH group (p = 0.04), and self-reported average improvement on a scale from 1 to 5 (1 being much worse and 5 being much better) was 2.8 for placebo and 4.7 for GSH (p = 0.004). Of the 13 primary and secondary outcomes examined, 11 outcomes favored the treatment group over the placebo group (p = 0.002), indicating a general tendency of improvement in the GSH group. No adverse events in the treatment group were noted. CONCLUSION: This pilot study indicates the promise of nebulized buffered GSH to ameliorate CF disease, and longer, larger, and improved studies of inhaled GSH are warranted.

Administration, Inhalation↗

PubMed2005

The effect of long-term storage on measured plasma lactate concentrations and prospective lactate results from a multicenter trial of antiretroviral therapy.

Plasma lactate measurements are typically performed in real time, limiting their usefulness in multicenter or longitudinal studies. To determine the stability of lactate specimens, blood was drawn in sodium fluoride/potassium oxalate tubes from 13 volunteers before and after 5 min of handgrip exercise to intentionally increase lactate concentrations. Plasma was stored at -70 degrees C. Aliquots were assayed in real time and after 1, 3, 6, 9, 12, 18, and 24 months. Real-time lactate concentrations measured at baseline ranged from 0.52 to 2.23 mmol/L before and from 2.91 to 11.04 mmol/L after handgrip exercise. Using a linear mixed model, the estimated change from baseline at month 24 was 1.67% (95% confidence interval, -0.70% to 4.03%) for pre-exercise samples and 0.39% (95% CI, -1.13% to 1.91%) for post-exercise samples. Stored serial specimens from 232 HIV-infected subjects in a multicenter trial of antiretroviral therapy were also assayed centrally. Among those, median plasma lactate increased from baseline to 64 weeks by 0.4 mmol/L with zidovudine+lamivudine treatment and by 0.6 mmol/L with didanosine+stavudine (each p<0.001 from baseline; p=0.04 for difference between groups over time). When performed as in this study, frozen storage with central batch lactate analysis is appropriate for prospectively collected samples in multicenter trials.

Acidosis, Lactic↗

PubMed2005

Early changes in 24-hour ambulatory blood pressure are associated with high normal albumin excretion rate in children with type 1 diabetes mellitus.

OBJECTIVE: The relationship between urinary albumin excretion rate (AER) and elevated blood pressure (BP) is unclear as a cause-effect phenomenon in the development of diabetic nephropathy. The aim of this study was to examine the association between AER, HbA1c and BP in children with normoalbuminuria. METHODS: 24-hour ambulatory BP assessment was performed in 78 children with type 1 diabetes mellitus (DM1), age mean +/- SD 13.4 +/- 2.7 yr, range 7.3-18.3 yr, DM1 duration mean +/- SD 6.6 +/- 2.9 yr, range 2.1-11.9 yr. Using generalised linear mixed models with systolic (SBP) and diastolic (DBP) blood pressure as dependent variables, the effects of AER and HbA1c were examined, adjusting for age, gender, DM1 duration and insulin dose. RESULTS: Patients with high normal AER (7-20 microg/min) had higher SBP during daytime and night-time compared to the low normal AER (< or = 7 microg/min) (mean +/- SD 118.20 +/- 7.98 and 110.33 +/- 7.08 mm Hg, p = 0.02; mean +/- SD 108.76 +/- 9.21 and 100.20 +/- 7.75 mm Hg, p = 0.03, respectively). DBP was also higher both during day- and night-time when compared to the < or = 7 microg/min group (mean +/- SD 73.40 +/- 6.50 and 64.86 +/- 5.67 mm Hg, p = 0.002; mean +/- SD 62.50 +/- 6.75 and 56.30 +/- 5.56 mm Hg, p = 0.03 day- and night-time, respectively). CONCLUSION: A rise in SBP and DBP is associated with increased levels of AER even within the normal range.

Adolescent↗

PubMed2006

Association genetics in Pinus taeda L. I. Wood property traits.

Genetic association is a powerful method for dissecting complex adaptive traits due to (i) fine-scale mapping resulting from historical recombination, (ii) wide coverage of phenotypic and genotypic variation within a single experiment, and (iii) the simultaneous discovery of loci and alleles. In this article, genetic association among single nucleotide polymorphisms (58 SNPs) from 20 wood- and drought-related candidate genes and an array of wood property traits with evolutionary and commercial importance, namely, earlywood and latewood specific gravity, percentage of latewood, earlywood microfibril angle, and wood chemistry (lignin and cellulose content), was tested using mixed linear models (MLMs) that account for relatedness among individuals by using a pairwise kinship matrix. Population structure, a common systematic bias in association studies, was assessed using 22 nuclear microsatellites. Different phenotype:genotype associations were found, some of them confirming previous evidence from collocation of QTL and genes in linkage maps (for example, 4cl and percentage of latewood) and two that involve nonsynonymous polymorphisms (cad SNP M28 with earlywood specific gravity and 4cl SNP M7 with percentage of latewood). The strongest genetic association found in this study was between allelic variation in alpha-tubulin, a gene involved in the formation of cortical microtubules, and earlywood microfibril angle. Intragenic LD decays rapidly in conifers; thus SNPs showing genetic association are likely to be located in close proximity to the causative polymorphisms. This first multigene association genetic study in forest trees has shown the feasibility of candidate gene strategies for dissecting complex adaptive traits, provided that genes belonging to key pathways and appropriate statistical tools are used. This approach is of particular utility in species such as conifers, where genomewide strategies are limited by their large genomes.

Chromosome Mapping↗

PubMed2003

Reduction in antibiotic use among US children, 1996-2000.

BACKGROUND: High rates of antibiotic prescribing to children contribute to antibiotic resistance in the community. The Centers for Disease Control and Prevention, in collaboration with other national and state level organizations, have actively promoted more judicious prescribing for children. OBJECTIVE: We sought to assess changes in the rate of antibiotic prescribing from 1996-2000 in 9 US health plans, patterns of diagnosis and treatment responsible for these trends, and changes in the use of first-line antimicrobial agents. DESIGN/METHODS: We analyzed claims data for dispensed medications and physician visits from 9 health plans. Each provided data on 25,000 children aged 3 months to <18 years enrolled between September 1, 1995, and August 31, 2000. Antibiotic dispensings were linked with an ambulatory visit claim to assign diagnosis. Antibiotic dispensings per person-year (antibiotics/p-y) were calculated for the age groups 3 months to <3 years, 3 years to <6 years, and 6 years to <18 years. The contribution of each diagnosis to changes in the overall rate of antibiotic use was determined. Generalized linear mixed models were used to test for trend and assess differences in rates by site. RESULTS: From 1996-2000, antibiotic rates for children 3 months to <3 years decreased from 2.46 to 1.89 antibiotics/p-y (24%); for children 3 years to <6 years from 1.47 to 1.09 antibiotics/p-y (25%); and for children 6 to <18 years from 0.85 to 0.69 antibiotics/p-y (16%). The reduction varied among health plans from 6% to 39% for children 3 months to <3 years. A decrease in prescriptions for otitis media accounted for 59% of the total decrease, and was primarily accounted for by a decrease in the rate of diagnosis of this condition. The proportion of first-line penicillins increased from 49% to 53%, with health plans with the lowest initial rates increasing most. CONCLUSIONS: Antibiotic prescribing decreased significantly between 1996 and 2000, concurrent with decreased frequency of diagnosis of potential bacterial infections, especially otitis media. Attention by public health and professional organizations and the news media to antibiotic resistance may have contributed to changes in diagnostic thresholds, resulting in more judicious prescribing.

Adolescent↗

PubMed2006

The influence of dynamic occlusal interferences on probing depth and attachment level: results of the Study of Health in Pomerania (SHIP).

BACKGROUND: The purpose of this study was to investigate potential associations between dynamic occlusal interferences and signs of periodontal disease in posterior teeth based on dental and medical measurements obtained from a population-based sample in the cross-sectional epidemiological study entitled, "Study of Health in Pomerania" (SHIP). METHODS: Medical history and dental and sociodemographic parameters of 2,980 representatively selected dentate subjects, 20 to 79 years of age, were collected. The analysis was performed on posterior teeth only using a mixed linear model that considers the clustered structure of the data. The model also was adjusted with respect to known risk factors for periodontal disease. RESULTS: The presence of non-working side contacts only was significantly related to probing depth (P<0.0001) and attachment loss (P=0.001). The presence of non-working side contacts and working side contacts on the same tooth was significantly related to increased probing depth (P=0.004) but not attachment level. The effect magnitude was a mean increase of 0.13 mm for probing depth and 0.14 mm in attachment loss. Known risk factors for periodontal disease that also showed significant associations with probing depth and attachment loss included male gender, age, smoking, education, and plaque score. Other factors significantly related to probing depth and/or attachment loss were tilted teeth, restored occlusal surfaces versus sound surfaces, elongated teeth, and tooth type (molar versus premolar). CONCLUSION: The effect of non-working contacts on periodontal disease status was discernible, but weak in terms of magnitude and specificity.

Adult↗

PubMed2004

Longitudinal effects of social support on the health and functioning of older women with heart disease.

This study examined the effects of: 1) four dimensions of social support, 2) the number of close social ties, and 3) marital status on the physical and psychological health and functioning of 471 women aged 60 years and over with heart disease. Linear mixed models were used to assess the impact of each baseline social relations predictor on health outcomes at four-, 12-, and 18-month follow-up intervals. A second set of models examined the association between change in support variables over time with concomitant change in health outcomes. Results indicated that baseline emotional/ informational support, positive social interaction, affectionate support, tangible support, number of close friends and relatives, and marital status all significantly predicted (p < .05) one or more health outcomes over time. Increases in positive social interaction and emotional support over time were significantly associated with concurrent improvement in all self-reported physical and psychological health outcomes. Interventions that enhance the availability of emotional/informational support and promote social interaction are needed for this population.

Aged↗

PubMedDate not supplied

Microleakage after thermocycling of 4 etch and rinse and 3 self-etch adhesives with and without a flowable composite lining.

This study evaluated the microleakage of composite fillings prepared with 4 etch and rinse and 3 self-etch adhesive systems after thermocycling. Also evaluated was the potential improvement of cavity sealing when utilizing a low charged resin lining for cavity preparations. Seventy recently extracted teeth were randomly allocated to 7 experimental adhesive systems: two 3-step etch and rinse adhesive systems, Scotchbond Multipurpose (SBMP) and Optibond Solo Plus (OS); two 2-step etch and rinse adhesive systems, referred to as "one-bottle," Scotchbond 1 (SB1) and Gluma Comfort Bond + Desensitizer (G); and 3 self-etch "all-in-one" adhesives, Adper Prompt-L-Pop (PLP), Xeno III (X-III) and iBond (iB). On each tooth, 2 rectangular cavities were prepared at the cemento-enamel junction: 1 cavity was prepared with adhesive and the hybrid composite and the second was filled with the same adhesive and a thin layer of flowable composite (Filtek Flow) under the resin composite (Z100). All teeth were thermocycled for 800 cycles (5 degrees C-55 degrees C, 30 seconds dwell time). Leakage was evaluated on a 6-point (0-5) severity scale for enamel and dentin on 4 interfaces for each restoration. The results are expressed as means +/- standard deviation (SD). Microleakage scores were analyzed by means of generalized linear mixed models (GLMM), assuming an ordinal logistic link function. Covariates in the model were: (1) adhesives, (2) fluid composite and (3) interface. The model also accounts for repeated measurements on the various teeth. The authors found that the mean score of microleakage per tooth was significantly higher at the enamel rather than at the dentin interfaces (1.21 +/- 0.51 and 0.87 +/- 0.48; p<0.0001). In this study, there was no significant difference among the 4 etch and rinse adhesive systems. On the other hand, these adhesives yielded smaller mean scores of microleakage than the 3 self-etch systems (respectively, 0.85 +/- 0.2 and 1.3 +/- 0.5; p<0.0001). Among the self-etch adhesives, microleakage was significantly greater for PLP (1.74 +/- 0.46) than for the other self-etch products (p<0.0001), while X-III, an intermediary strong self-etch, was found to be as good as the etch and rinse systems, with a mean score of 0.97 +/- 0.27. In addition, results have also shown that an under layer of flowable composite significantly improved the water tightness of the PLP adhesive restorations (p=0.042). This in vitro study concluded that the self-etch adhesives remain less effective than etch and rinse. Nevertheless, X-III, a self-etch adhesive, showed acceptable performance in accordance with this study's 6-point severity scale of microleakage, but this needs to be confirmed in further clinical studies. On the other hand, this study failed to reveal that the addition of a thin layer of fluid composite improved the water tightness of the restoration, except for PLP.

Acid Etching, Dental↗

PubMed2004

Prevalence of anthelmintic resistant cyathostomes on horse farms.

OBJECTIVE: To determine prevalence of anthelmintic resistance in cyathostome nematodes of horses in the southern United States. DESIGN: Cross-sectional study. ANIMALS: 786 horses on 44 farms and stables in Georgia, South Carolina, Florida, Kentucky, and Louisiana. PROCEDURE: Fecal egg count (FEC) reduction tests were performed on 44 large farms and stables. Horses on each farm were treated with an oral paste formulation of fenbendazole, oxibendazole, pyrantel pamoate, or ivermectin at recommended label dosages. A mixed linear model was fitted to the percentage reduction in FEC, accounting for differences among farms, states, ages, treatments, and treatment by state interactions. RESULTS: By use of a conservative measure of resistance (< 80% reduction), the percentage of farms with anthelmintic-resistant cyathostomes was 97.7%, 0%, 53.5%, and 40.5% for fenbendazole, ivermectin, oxibendazole, and pyrantel pamoate, respectively. Mean percentage reductions in FEC for all farms were 24.8%, 99.9%, 73.8%, and 78.6% for fenbendazole, ivermectin, oxibendazole, and pyrantel pamoate, respectively. Pairwise contrasts between states for each treatment revealed that in almost all instances, there were no significant differences in results between states. CONCLUSIONS AND CLINICAL RELEVANCE: The prevalence of resistance found in this study was higher than that reported previously, suggesting that anthelmintic resistance in equine cyathostomes is becoming a major problem. Furthermore, data from these 5 southern states, which are geographically and physiographically distinct, were remarkably similar. This suggests that drug resistance in cyathostomes is highly prevalent throughout the entire southern United States and probably nationwide.

Animals↗

PubMed2004

A comparison of human muscle temperature increases during 3-MHz continuous and pulsed ultrasound with equivalent temporal average intensities.

STUDY DESIGN: A repeated-measure crossover design was used. The independent variable was the type of ultrasound (pulsed or continuous) and the dependent variable was intramuscular temperature. OBJECTIVE: To compare changes in intramuscular temperature resulting from the use of pulsed ultrasound versus continuous ultrasound with an equivalent spatial average temporal average (SATA) intensity. BACKGROUND: There is a lack of research on the heat-generating capabilities of pulsed ultrasound within human muscle. METHODS AND MEASURES: The subjects were 16 healthy volunteers (mean age +/- SD, 21.3 +/- 2.5 years). Each subject was treated with pulsed ultrasound (3 MHz, 1.0 W/cm2, 50% duty cycle, for 10 minutes) and continuous ultrasound (3 MHz, 0.5 W/cm2, for 10 minutes) during a single testing session. Tissue temperature returned to baseline and stabilized between treatments and treatment order was randomized. Tissue temperature was measured every 30 seconds using a 26-gauge needle microprobe inserted at a depth of 2 cm in the left medial gastrocnemius muscle. Data were analyzed using a linear mixed model. RESULTS: Treatment with continuous ultrasound produced a mean (+/-SD) temperature increase of 2.8 degrees C +/- 0.8 degrees C above baseline. Treatment with pulsed ultrasound produced a mean (+/-SD) temperature increase of 2.8 degrees C +/- 0.7 degrees C above baseline. Statistical analysis revealed no significant differences in either the extent or rate of temperature increases between the 2 modes of ultrasound application. CONCLUSION: Pulsed ultrasound (3 MHz, 1.0 W/cm2, 50% duty cycle, for 10 minutes) produces similar intramuscular temperature increases as continuous ultrasound (3 MHz, 0.5 W/cm2, for 10 minutes) at a 2-cm depth in the human gastrocnemius. Spatial average temporal average intensity is an important consideration when selecting pulsed ultrasound parameters intended to deliver nonthermal effects.

Adult↗

PubMed1992

An embryo transfer study of reciprocal cross differences in growth and carcass traits of Duroc and Landrace pigs.

Reciprocal cross differences have been reported for growth rate and carcass traits in F1 pigs with the Duroc (D) as a parent breed. Such differences are synonymous with maternal effects if effects of sex linkage and genomic imprinting are negligible. In the present study, transfer of embryos (ET) to paternal breed recipients partitioned effects occurring at or before fertilization from postfertilization effects for growth and carcass traits in F1 D-Landrace (L) pigs. Fifteen boars sired 115 F1 litters, 49 produced by ET. Growth rate of 349 barrows and 361 gilts and carcass measurements on 256 barrows and 159 gilts were analyzed assuming mixed linear models with animal and litter as random effects. Contrasts among genotype (D x L, L x D)- treatment (ET, non-ET) means were tested. Reciprocal cross differences were not detected for growth rate or for carcass weight, length, average backfat thickness, estimated carcass lean, or lean per day of age. Reciprocal cross differences for 10th rib backfat thickness (BF) and longissimus muscle area (LMA) were detected only in barrows. The sexual dichotomy for reciprocal cross differences followed expectations for a Y-linked gene(s), consistent with the fact that reciprocal D-L crossbred barrows exhibited a paternal effect, with responses more like the sire breed than the dam breed. Barrows that were non-ET from D sires and L dams had 3.9 cm2 larger LMA and 5.8 mm less BF than barrows from L sires and D dams (P less than .001). Barrows from ET sired by D boars had 3.8 cm2 larger LMA than did barrows from ET sired by L boars (P less than .001), although no difference was detected for BF. Barrows sired by D boars reared in a D postfertilization environment (ET) had 6.2 cm2 greater LMA and 4.1 mm less BF (P less than .05) than barrows sired by L boars gestated and reared by D dams (non-ET). Barrows sired by D boars reared by L dams (non-ET) had 1.5 cm2 greater LMA and 2.3 mm less BF (P greater than .10) than barrows sired by L boars reared by L dams (ET). In conclusion, reciprocal cross differences detected for BF and LMA in barrows were established before or at fertilization and seemed to be Y-linked.

Adipose Tissue↗