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CONTEXT: Mothers are in an important position to prevent obesity in their children by shaping early diet and activity patterns. However, many mothers of overweight preschool children are not worried about their child's weight. OBJECTIVE: To explore mothers' perceptions about how they determine when a child is overweight, why children become overweight, and what barriers exist to preventing or managing childhood obesity. DESIGN: Three focus groups with 6 participants in each. Participant comments were transcribed and analyzed. Themes were coded independently by the 6 authors who then agreed on common themes. SETTING: A clinic of the Special Supplemental Nutrition Program for Women, Infants, and Children in Cincinnati, Ohio. PARTICIPANTS: Eighteen low-income mothers (13 black, 5 white) of preschool children (mean age of 44 months) who were at-risk for later obesity. All but 1 mother had a body mass index (BMI) >/=25 kg/m(2), and 12 mothers had a BMI >/=30 kg/m(2). All but 1 child had a BMI >/=85th percentile for age and sex, and 7 had a BMI >/=95th percentile. Results. Mothers did not define overweight or obese in their children according to how height and weight measurements were plotted on the standard growth charts used by health professionals. Instead, mothers were more likely to consider being teased about weight or developing limitations in physical activity as indicators of their child being overweight. Children were not believed to be overweight if they were active and had a healthy diet and/or a good appetite. Mothers described overweight children as thick or solid. Mothers believed that an inherited tendency to be overweight was likely to be expressed in the child regardless of environmental factors. In trying to shape their children's eating, mothers believed that their control over the child's diet was challenged by other family members. If a child was hungry, despite having just eaten, it was emotionally difficult for mothers to deny additional food. CONCLUSIONS: Health professionals should not assume that defining overweight according to the growth charts has meaning for all mothers. Despite differing perceptions between mothers and health professionals about the definition of overweight, both groups agree that children should be physically active and have healthy diets. Health professionals may be more effective in preventing childhood obesity by focusing on these goals that they share with mothers, rather than on labeling children as overweight.

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To better explore possible factors that may lead to childhood obesity, we developed and analyzed two new instruments that assess maternal feeding practices and beliefs. The Infant Feeding Questionnaire (IFQ) assesses feeding during the entire first year of life and was administered to 453 mothers of children 11 to 23 months old. The Preschooler Feeding Questionnaire (PFQ) assesses feeding of young children between the ages of 2 to 5 years and was administered to 634 mothers of children this age. Each questionnaire was factor analyzed and mean factor scores were calculated and linked with the children's measured and mothers' self-reported weight and height. Mean factor scores from the IFQ and PFQ were compared between mothers who were obese (body mass index > or = 30 kg/m2) and those who were nonobese, between those who did and those who did not have an overweight child (weight-for-height > or = 90th percentile), and between those who had a low income (< or = 185% of the poverty level) and those who had a high income. To control for confounding variables and to detect interaction among variables, hierarchical linear regression was used. Results from this study did not suggest that there is a particular "feeding style" that is associated with overweight in young children; however, there were differences found in feeding behaviors between high and low income mothers.

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CONTEXT: Childhood obesity is a major public health problem, and prevention efforts should begin early in life and involve parents. OBJECTIVE: To determine what factors are associated with mothers' failure to perceive when their preschool children are overweight. DESIGN: Cross-sectional survey. SETTINGS: Offices of private pediatricians and clinics of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). PARTICIPANTS: Six hundred twenty-two mothers with children 23 to 60 months of age. MAIN OUTCOME MEASURES: Maternal demographic variables, maternal self-reported height and weight, and children's measured height and weight. Mothers were asked whether they considered themselves or their children overweight. RESULTS: Forty-five percent of mothers had low education (high school degree or less) and 55% had high education (some college or more). Obesity (body mass index: >/=30 kg/m(2)) was more common in the low education group of mothers (30% vs 17%), and their children tended to be more overweight (weight-for-height percentile: >/=90th; 19% vs 14%). Ninety-five percent of obese mothers believed that they were overweight, with no difference between education groups. However, 79% of mothers failed to perceive their overweight child as overweight. Among the 99 mothers with overweight children, low maternal education was associated with a failure to perceive their children as overweight after adjusting for low family income (

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The sigE gene of Streptomyces coelicolor A3(2) encodes an RNA polymerase sigma factor belonging to the extracytoplasmic function (ECF) subfamily. Constructed sigE deletion and disruption mutants were more sensitive than the parent to muramidases such as hen egg white lysozyme and to the CwlA amidase from Bacillus subtilis. This correlated with an altered muropeptide profile, as determined by reverse-phase high-performance liquid chromatography analysis of lytic digests of purified peptidoglycan. The sigE mutants required high levels of magnesium for normal growth and sporulation, overproducing the antibiotic actinorhodin and forming crenellated colonies in its absence. Together, these data suggest that sigE is required for normal cell wall structure. The role of sigmaE was further investigated by analyzing the expression of hrdD, which is partially sigE dependent. The hrdD gene, which encodes the sigmaHrdD subunit of RNA polymerase, is transcribed from two promoters, hrdDp1 and hrdDp2, both similar to promoters recognized by other ECF sigma factors. The activities of hrdDp1 and hrdDp2 were reduced 20- and 3-fold, respectively, in sigE mutants, although only hrdDp1 was recognized by EsigmaE in vitro. Growth on media deficient in magnesium caused the induction of both hrdD promoters in a sigE-dependent manner.

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In the non-motile mycelial organism Streptomyces coelicolor A3(2), the sporulation gene whiG encodes a protein that closely resembles RNA polymerase sigma factors such as sigma D of Bacillus subtilis, which mainly control motility and chemotaxis genes. Here, we show that the whiG gene product, purified from an Escherichia coli strain carrying an expression construct, could activate E. coli core RNA polymerase in vitro to transcribe a sigma D-dependent motility-related promoter from B. subtilis. Such RNA polymerase holoenzyme preparations could also transcribe from an S. coelicolor promoter, PTH4, previously shown to require an intact whiG gene for in-vivo transcription. The in-vivo dependence on whiG was therefore shown to be direct. Unusually, the initiation of PTH4 transcription in vitro depended on the provision of appropriate dinucleotides. The whiG-dependent PTH4 transcription unit consisted of a single gene, orfTH4. Sequence comparisons suggested that the gene product was a member of a small group of proteins that include the B. subtilis and E. coli ProX proteins. Though none of these proteins shared more than about 30% of extended primary sequence identity, they had similar size and hydropathy profiles, and could be aligned end to end to reveal a mosaic of similarities. The ProX proteins of B. subtilis and E. coli are implicated in glycine betaine transport in response to hyperosmotic stress. However, disruption of orfTH4 did not cause any obvious phenotypic changes in growth or development on media of varying osmotic strengths.

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whiE is a complex locus that specifies the polyketide spore pigment in Streptomyces coelicolor A3(2). Two divergently oriented promoters, whiEP1 and whiEP2, were identified in the whiE gene cluster, and their activities were analyzed during colony development in wild-type and sporulation-deficient strains. Both promoters were developmentally regulated; whiEP1 and whiEP2 transcripts were detected transiently at approximately the time when sporulation septa were observed in the aerial hyphae, and transcription from both promoters depended on each of the six known "early" whi genes required for sporulation septum formation (whiA, -B, -G, -H, -I, and -J). Mutation of the late sporulation-specific sigma factor gene, sigF, had no effect on the activity of whiEP1 but blocked transcription from whiEP2. However, sigmaF-containing holoenzyme was not sufficient to direct transcription of whiEP2 in vitro. The whiEP2 promoter controls expression of whiE ORFVIII, encoding a putative flavin adenine dinucleotide-dependent hydroxylase that catalyzes a late tailoring step in the spore pigment biosynthetic pathway. Disruption of whiE ORFVIII causes a change in spore color, from grey to greenish (T.-W. Yu and D. A. Hopwood, Microbiology 141:2779-2791, 1995). Consistent with these observations, construction of a sigF null mutant of S. coelicolor M145 caused the same change in spore color, showing that disruption of sigF in S. coelicolor changes the nature of the spore pigment rather than preventing its synthesis altogether.

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Nucleotide sequences that surrounded ATG initiation codons were examined in jawless and cartilaginous fish complementary DNA sequences. Both thymidine and cytidine residues were underrepresented at positions near the initiation codon, while an extremely high frequency of purine nucleotides was observed at position -3. Statistical analysis (chi2) indicated that the greatest compositional bias occurred at nucleotide positions -3 and +4, and suggested that a relatively short consensus sequence surrounded AUG initiation codons of primitive fish genes. ATG triplets within 5' leader sequences were flanked by nucleotides different from those that surrounded ATG initiation codons. Dinucleotide frequency analysis indicated a deficiency in TA and an excess in AA around initiation codons. DNA sequence analysis suggested that low CpG conversion occurred 5' to the translation start of primitive fish genes. The conservation of consensus sequences around initiation codons of primitive fish genes underscores the importance of nucleotide composition for initiation of translation.

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The phsA gene encodes phenoxazinone synthase (PHS), which catalyses the penultimate step in the pathway for actinomycin biosynthesis in Streptomyces antibioticus. The phsA promoter strikingly resembles a putative Streptomyces sigma E cognate promoter, and purified E sigma E holoenzyme transcribed the phsA promoter in vitro. However, the phsA promoter was still active in an S. antibioticus sigE null mutant and the level of PHS activity was unaffected. Despite this, disruption of sigE blocked actinomycin production completely. The loss of actinomycin production correlated with a 10-fold decrease in the activity of actinomycin synthetase I, the enzyme which catalyses the activation of the precursor of the actinomycin chromophore.

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The nucleotide sequences of the small intergenic region (SIR) and the gene encoding the coat protein of 12 maize streak virus (MSV) isolates from different geographic locations have been determined. These have been used to assess the variability of the virus and to construct evolutionary dendrograms. For the viruses analyzed, the maximum levels of sequence divergence were found to be 10.9% and 2.0% at the nucleotide and amino acid levels, respectively. A genetically distinct strain of MSV was collected from islands in the Indian ocean. The significance of these findings for detection of the virus in epidemiological studies and breeding of resistant plant varieties is discussed.

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Dinucleotide frequencies and codon usage in terms of strong-weak codon choices were examined in gene coding regions of 5 jawless and cartilaginous fish species. These dinucleotide frequencies were then compared to gene-coding regions from a vertebrate and an invertebrate species. These primitive vertebrate fishes exhibited species specificity in the hierarchy of dinucleotide frequencies. The most frequently occurring dinucleotide varied among coding regions of jawless and cartilaginous fishes, but it always contained G. Of the 16 dinucleotides, TA had the lowest frequency of occurrence in all species, and it had considerably lower frequencies in jawless fish genes than in cartilaginous fish genes. Dinucleotide frequency analysis suggested CpG conversion to TG in ray genes. Strong-weak codon usage analysis indicated that all 5 fish species used strong-weak-strong bonding codons most frequently; furthermore, each species used any-weak-strong codons in greater than expected levels. Gene coding regions from all 5 species exhibited a bias toward strong bonding nucleotides at codon position 3, with the greatest bias in sea lamprey genes. This bias may reflect the overall G+C content of localized regions of chromosomal DNA in which these genes reside.

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The application of the polymerase chain reaction (PCR) method of DNA amplification for the isolation of full-length, infectious clones of geminiviruses is described. Non-overlapping, abutting 20-mer oligonucleotide primers were used to produce a linear product from the circular geminivirus genomic template. Clones of African cassava mosaic virus (ACMV) DNA A, obtained by this method, were infectious following mechanical inoculation (in the presence of ACMV DNA B) onto Nicotiana benthamiana. Normal ACMV symptoms resulted and typical geminate viral particles were detected by electron microscopy. The use of PCR for the detection and production of full-length, infectious geminivirus clones is discussed.

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Bacterial immunoglobulin-binding proteins expressed on the surface of group A streptococci represent a heterogeneous family of functionally related proteins. In this report, we describe efficient methods for extracting immunoglobulin-binding proteins and classifying them functionally and antigenically. A common characteristic of immunoglobulin-binding proteins expressed by group A streptococci appears to be the absence of internal methionine residues in the binding protein. This has enabled development of a rapid, efficient, cyanogen bromide-based extraction procedure for solubilizing these molecules from intact bacteria. Studies carried out with a series of monospecific polyclonal antibodies prepared in chickens have identified two major antigenic classes of immunoglobulin-binding proteins. The methods described in this report facilitate a rapid functional and serological screening of immunoglobulin-binding proteins that should now enable detailed epidemiological studies of the importance of these molecules in group A streptococcal infections and their relationship to other surface proteins, in particular, the antiphagocytic M protein.

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The infectious genome of a Kenyan isolate of Panicum streak virus (PSV) has been cloned and sequenced. Infection of host plants was done using an Agrobacterium binary vector containing a partial repeat of the genome. Progeny virus from resultant infections proved to be transmissible by the leafhopper Cicadulina mbila (Naude). Comparisons of the amino acid sequences of PSV DNA-encoded proteins with those of previously characterized geminiviruses infecting monocotyledonous plants, including maize streak virus, revealed high levels of identity. The evolutionary relationship between PSV and other geminiviruses infecting monocotyledons is discussed.

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Increased rates of nosocomial infection caused by filamentous fungi in immunocompromised patients prompted microbiologic surveillance of the central air handling systems in our hospital. During a 4-year period, Penicillium species were isolated from 47 patients, including two with surgical wound infections caused by Penicillium. Counts of Penicillium in operating room air were much higher (195 colony-forming units [CFU]/m3) than in 95% filtered corridor air (14.6 CFU/m3; p less than 0.01). Ventilation ducts and terminal units lined with fiberglass in the operating room air handling system were heavily contaminated by Penicillium; the fiberglass was also contaminated with Aspergillus species. Corrective measures included filter replacement and decontamination of the ventilation system with aerosolized chlorine solution. Although operating room air remained free of filamentous fungi during the next 7 months, contamination eventually recurred and required repeated decontamination. We believe that certification guidelines are highly desirable for hospital ventilation systems, especially if the system serves immunocompromised patients.

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Oxidation by molecular oxygen converted the 22Kdalton glycoprotein from rat ventral prostate into a 34K species and this reaction could be reversed by thiol reducing reagent. Measurement of the level of the 22Kdalton glycoprotein in prostatic cytosol by the radial immunodiffusion technique showed that changes in the 22Kdalton glycoprotein concentration in response to androgen withdrawal and replacement were slow in comparison to androgen regulated levels of mRNA coding for the protein. (3) Charcoal absorption steroid binding assays of the 22Kdalton glycoprotein revealed that the protein did not bind testosterone, estradiol, progesterone or corticosterone. These results indicate that the 22Kdalton glycoprotein is metabolically stable, not steroid-binding, and exists as an oligomer through disulfide crosslinking.

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An abundant 20-kilodalton protein has been isolated from the cytosol fraction of rat ventral prostate by ammonium sulfate precipitation, DNA-cellulose chromatography, and gel filtration. The purified 20K protein is a glycoprotein, containing 11% hexose by weight. It contains no fucose, hexosamine, or sialic acid. The 20K protein does not bind androgen. Binding of the 20K protein to DNA is nonspecific, showing affinity toward DNAs of various tissue origins, as well as poly(dA-dT), poly(rI-rC), and phosphocellulose. The 20K protein comprises about 9% of the total cytosolic proteins in rat ventral prostate. Examination of eight different rat organs, including prostate secretion, lateral and dorsal prostates, and rat ejaculate, for the presence of the 20K protein by double immunodiffusion analysis revealed that the protein is a rat ventral prostate specific secretory protein. Hybridization of prostatic poly(A) RNA with a cloned cDNA coding for the 20K protein indicated that the synthesis of the 20K protein is regulated by testosterone at the mRNA level.

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