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1.
Pediatric constipation/encopresis is thought to be due, in part, to paradoxical constriction of the external anal sphincter (EAS) muscle during attempted defecation. This inappropriate contraction can lead to delayed, impacted, painful, and infrequent bowel movements. Standard Medical Care (SMC) involves disimpaction with enemas, followed by laxative therapy and diet modification, to maintain frequent soft stools. Using the case control method, the efficacy of SMC alone was compared with SMC plus EAS electromyographic biofeedback aimed at eliminating paradoxical contraction. Thirteen consecutive chronically constipated children received SMC plus biofeedback, and were compared with 13 age- and sex-matched children who received only SMC. Biofeedback subjects demonstrated post-treatment elimination of EAS paradoxical constriction. At 16 months follow-up parents of biofeedback children reported significantly greater improvement in constipation, encopresis, laxative use, and painful bowel movements compared to SMC.This research report was supported by the NIH under grant No. RO1 HD 28160.  相似文献   
2.
The relative stability and magnitude of genetic and environmental effects underlying major dimensions of adolescent personality across time were investigated. The Junior Eysenck Personality Questionnaire was administered to over 540 twin pairs at ages 12, 14 and 16 years. Their personality scores were analyzed using genetic simplex modeling which explicitly took into account the longitudinal nature of the data. With the exception of the dimension lie, multivariate model fitting results revealed that familial aggregation was entirely explained by additive genetic effects. Results from simplex model fitting suggest that large proportions of the additive genetic variance observed at ages 14 and 16 years could be explained by genetic effects present at the age of 12 years. There was also evidence for smaller but significant genetic innovations at 14 and 16 years of age for male and female neuroticism, at 14 years for male extraversion, at 14 and 16 years for female psychoticism, and at 14 years for male psychoticism.  相似文献   
3.
A microarray (LungCaGxE), based on Illumina BeadChip technology, was developed for high-resolution genotyping of genes that are candidates for involvement in environmentally driven aspects of lung cancer oncogenesis and/or tumor growth. The iterative array design process illustrates techniques for managing large panels of candidate genes and optimizing marker selection, aided by a new bioinformatics pipeline component, Tagger Batch Assistant. The LungCaGxE platform targets 298 genes and the proximal genetic regions in which they are located, using ∼13,000 DNA single nucleotide polymorphisms (SNPs), which include haplotype linkage markers with a minimum allele frequency of 1% and additional specifically targeted SNPs, for which published reports have indicated functional consequences or associations with lung cancer or other smoking-related diseases. The overall assay conversion rate was 98.9%; 99.0% of markers with a minimum Illumina design score of 0.6 successfully generated allele calls using genomic DNA from a study population of 1873 lung-cancer patients and controls.  相似文献   
4.
Gene–environment interactions have been extensively studied in lung cancer. It is likely that several genetic polymorphisms cooperate in increasing the individual risk. Therefore, the study of gene–gene interactions might be important to identify high-susceptibility subgroups. GSEC is an initiative aimed at collecting available data sets on metabolic polymorphisms and the risks of cancer at several sites and performing pooled analyses of the original data. Authors of published papers have provided original data sets. The present paper refers to gene–gene interactions in lung cancer and considers three polymorphisms in three metabolic genes: CYP1A1, GSTM1 and GSTT1. The present analyses compare the gene–gene interactions of the CYP1A1*2A, GSTM1 and GSTT1 polymorphisms from studies on lung cancer conducted in Europe and the USA between 1991 and 2000. Only Caucasians have been included. The data set includes 1466 cases and 1488 controls. The only clear-cut association was found with CYP1A1*2A. This association remained unchanged after stratification by polymorphisms in other genes (with an odds ratio [OR] of approximately 2.5), except when interaction with GSTM1 was considered. When the OR for CYP1A1*2A was stratified according to the GSTM1 genotype, the OR was increased only among the subjects who had the null (homozygous deletion) GSTM1 genotype (OR=2.8, 95% CI=0.9–8.4). The odds ratio for the interactive term (CYP1A1*2A by GSTM1) in logistic regression was 2.7 (95% CI=0.5–15.3). An association between lung cancer and the homozygous CYP1A1*2A genotype is confirmed. An apparent and biologically plausible interaction is suggested between this genotype and GSTM1.  相似文献   
5.
The vesicular stomatitis virus (VSV) matrix (M) protein plays a major role in the virus-induced inhibition of host gene expression. It has been proposed that the inhibition of host gene expression by M protein is responsible for suppressing activation of host interferon gene expression. Most wild-type (wt) strains of VSV induce little if any interferon gene expression. Interferon-inducing mutants of VSV have been isolated previously, many of which contain mutations in their M proteins. However, it was not known whether these M protein mutations were responsible for the interferon-inducing phenotype of these viruses. Alternatively, mutations in other genes besides the M gene may enhance the ability of VSV to induce interferons. These hypotheses were tested by transfecting cells with mRNA expressing wt and mutant M proteins in the absence of other viral components and determining their ability to inhibit interferon gene expression. The M protein mutations were the M51R mutation originally found in the tsO82 and T1026R1 mutant viruses, the double substitution V221F and S226R found in the TP3 mutant virus, and the triple substitution E213A, V221F, and S226R found in the TP2 mutant virus. wt M proteins suppressed expression of luciferase from the simian virus 40 promoter and from the beta interferon (IFN-beta) promoter, while M proteins of interferon-inducing viruses were unable to inhibit luciferase expression from either promoter. The M genes of the interferon-inducing mutants of VSV were incorporated into the wt background of a recombinant VSV infectious cDNA clone. The resulting recombinant viruses were tested for their ability to activate interferon gene expression and for their ability to inhibit host RNA and protein synthesis. Each of the recombinant viruses containing M protein mutations induced expression of a luciferase reporter gene driven by the IFN-beta promoter and induced production of interferon bioactivity more effectively than viruses containing wt M proteins. Furthermore, the M protein mutant viruses were defective in their ability to inhibit both host RNA synthesis and host protein synthesis. These data support the idea that wt M protein suppresses interferon gene expression through the general inhibition of host RNA and protein synthesis.  相似文献   
6.
7.
While characterizing the intestinal bacterial community of broiler chickens, we detected -proteobacterial DNA in the ilea of 3-day-old commercial broiler chicks (J. Lu, U. Idris, B. Harmon, C. Hofacre, J. J. Maurer, and M. D. Lee, Appl. Environ. Microbiol. 69:6816-6824, 2003). The sequences exhibited high levels of similarity to Campylobacter jejuni and Campylobacter coli sequences, suggesting that chickens can carry Campylobacter at a very young age. Campylobacter sp. was detected by PCR in all samples collected from the ilea of chicks that were 3 to 49 days old; however, it was detected only in the cecal contents of chickens that were at least 21 days old. In order to determine whether the presence of Campylobacter DNA in young chicks was due to ingestion of the bacteria in food or water, we obtained commercial broiler hatching eggs, which were incubated in a research facility until the chicks hatched. DNA sequencing of the amplicons resulting from Campylobacter-specific 16S PCR performed with the ileal, cecal, and yolk contents of the day-of-hatching chicks revealed that Campylobacter DNA was present before the chicks consumed food or water. The 16S rRNA sequences exhibited 99% similarity to C. jejuni and C. coli sequences and 95 to 98% similarity to sequences of other thermophilic Campylobacter species, such as C. lari and C. upsaliensis. The presence of C. coli DNA was detected by specific PCR in the samples from chicks obtained from a commercial hatchery; however, no Campylobacter was detected by culturing. In order to determine whether the same strains of bacteria were present in multiple levels of the integrator, we cultured Campylobacter sp. from a flock of broiler breeders and their 6-week-old progeny that resided on a commercial broiler farm. The broiler breeders had been given fluoroquinolone antibiotics, and we sought to determine whether the same fluoroquinolone-resistant strain was present in their progeny. The isolates were typed by pulsed-field gel electrophoresis, which confirmed that the parental and progeny flocks contained the same strain of fluoroquinolone-resistant C. coli. These data indicate that resistant C. coli can be present in multiple levels of an integrated poultry system and demonstrated that molecular techniques or more sensitive culture methods may be necessary to detect early colonization by Campylobacter in broiler chicks.  相似文献   
8.
Acknowledgments     
One of the major causes of worldwide amphibian declines is a skin infection caused by a pathogenic chytrid fungus (Batrachochytrium dendrobatidis). This study documents the interactions between this pathogen and a susceptible amphibian host, the boreal toad (Bufo boreas). The amount of time following exposure until death is influenced by the dosage of infectious zoospores, duration of exposure, and body size of the toad. The significant relation between dosage and the number of days survived (dose-response curve) supports the hypothesis that the degree of infection must reach a particular threshold of about 107–108 zoosporangia before death results. Variation in air temperature between 12°C and 23°C had no significant effect on survival time. The infection can be transmitted from infected to healthy animals by contact with water containing zoospores; no physical contact between animals is required. These results are correlated with observations on the population biology of boreal toads in which mortalities associated with B. dendrobatidis have been identified.  相似文献   
9.
Silent information regulator 2 (Sir2) family of enzymes has been implicated in many cellular processes that include histone deacetylation, gene silencing, chromosomal stability, and aging. Yeast Sir2 and several homologues have been shown to be NAD(+)-dependent histone/protein deacetylases. Previously, it was demonstrated that the yeast enzymes catalyze a unique reaction mechanism in which the cleavage of NAD(+) and the deacetylation of substrate are coupled with the formation of O-acetyl-ADP-ribose, a novel metabolite. We demonstrate that the production of O-acetyl-ADP-ribose is evolutionarily conserved among Sir2-like enzymes from yeast, Drosophila, and human. Also, endogenous yeast Sir2 complex from telomeres was shown to generate O-acetyl-ADP-ribose. By using a quantitative microinjection assay to examine the possible biological function(s) of this newly discovered metabolite, we demonstrate that O-acetyl-ADP-ribose causes a delay/block in oocyte maturation and results in a delay/block in embryo cell division in blastomeres. This effect was mimicked by injection of low nanomolar levels of active enzyme but not with a catalytically impaired mutant, indicating that the enzymatic activity is essential for the observed effects. In cell-free oocyte extracts, we demonstrate the existence of cellular enzymes that can efficiently utilize O-acetyl-ADP-ribose.  相似文献   
10.
Abstract Observations of the large earth bumblebee, Bombus terrestris (L.), in native vegetation were collated to determine the extent to which this exotic species has invaded Tasmanian native vegetation during the first 9 years after its introduction. The range of B. terrestris now encompasses all of Tasmania's major vegetation types, altitudes from sea level to 1260m a.s.L, and the entire breadth of annual precipitation in the state from more than 3200 mm to less than 600 mm. Observations of workers carrying pollen, together with the presence of large numbers of bumblebees at many localities across this range indicate that colonies are frequently established in native vegetation. Evidence that colonies are often successful was obtained from repeated observations of the species during more than 1 year at particular sites. Unequivocal evidence of colonies was obtained from six National Parks, including four of the five in the Tasmanian Wilderness World Heritage Area (WHA). Indeed, the species has been present in the WHA for at least as long as it has in the city of Hobart, where it was first recorded. In southwestern Tasmania, evidence of colonies was obtained up to 40km from gardens, 61 km from small towns and 93 km from large towns. Hence, contrary to previous suggestions, the species is established in the most remote parts of Tasmania and is not dependent on introduced garden plants. Given their strong record of invasion, it is likely that B. terrestris will form feral populations on the mainland of Australia and in many other parts of the world if introduced. Because of their likely negative impacts on native animals and plants, and potential to enhance seed production in weeds, the spread of bumblebees should be avoided.  相似文献   
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