Nutrition and Physical Activity Program to Attenuate Obesity and Promote Physical and Metabolic Fitness in Elementary School Children

Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was ?16 % less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con.     

Potential of fungi as biocontrol agents of polyphagotarsonemus latus (Acari: Tarsonemidae)

Infection of broad mites, Polyphagotarsonemus latus, by conidia of Beauveria bassiana, Hirsutella thompsonii, and Paecilomyces fumosoroseus conidia was investigated in the laboratory under controlled temperature and moisture conditions. Infection of P. latus by the fungus (LC₅₀) was related positively to the 1.16 × 10⁶ B. bassiana conidia per ml, 2.39 × 10³ H. thompsonii conidia per ml, and 1.29 × 10⁵ P. fumosoroseus conidia per ml. Mortality caused by B. bassiana occurred the fastest among densities fluctuating between 65 and 125 mites per leaf. The pathogens B. bassiana and P. fumosoroseus, adjuvants (oil and molasses), and the acaricide ABG6364, a microbial insecticide containing the Beta-exotoxin of Bacillus thuringiensis were evaluated for efficacy against P. latus in a greenhouse test. The B. bassiana treated plants had the greatest and most persistent effect on percentage mortality of total broad mites present per leaf (88 %) followed by the acaricide ABG6364. Use of adjuvants (oil and molasses) did not increase infection of P. latus.     

Effect on lipoprotein profile of replacing butter with margarine in a low fat diet: randomised crossover study with hypercholesterolaemic subjects.

OBJECTIVE--To examine the effect on lipid and lipoprotein concentrations when butter or an unsaturated margarine is used for cooking or spreading in a reduced fat diet. DESIGN--Randomised crossover study with two intervention periods of six weeks'' duration separated by a five week washout. SETTING--Community setting in New Zealand. SUBJECTS--49 volunteers with polygenic hypercholesterolaemia and baseline total cholesterol concentration in the range 5.5-7.9 mmol/l. MAIN OUTCOME MEASURES--Concentrations of total and low density lipoprotein, Lp(a) lipoprotein, high density lipoprotein, apolipoprotein B 100, and apolipoprotein A I. RESULTS--Concentrations of low density lipoprotein cholesterol and apolipoprotein B were about 10% lower with margarine than with butter. Lp(a) lipoprotein and high density lipoprotein cholesterol concentrations were similar with the two diets. CONCLUSION--Despite concerns about adverse effects on lipoproteins of trans fatty acids in margarines, the use of unsaturated margarine rather than butter by hypercholesterolaemic people is associated with a lipoprotein profile that would be expected to reduce cardiovascular risk.     

PCR-based gene targeting of the inducible nitric oxide synthase (NOS2) locus in murine ES cells,a new and more cost-effective approach

Gene targeting by double homologous recombination in murine embryonic stem (ES) cells is a powerful tool used to study the cellular consequences of specific genetic mutations. A typical targeting construct consists of a neomycin phosphotransferase (neo) gene flanked by genomic DNA fragments that are homologous to sequences in the target chromosomal locus. Homologous DNA fragments are typically cloned from a murine genomic DNA library. Here we describe an alternative approach whereby the inducible nitric oxide synthase (NOS2) gene locus is partially mapped and homologous DNA sequences obtained using a long-range PCR method. A 7 kb NOS2 amplicon is used to construct a targeting vector where theneo gene is flanked by PCR-derived homologous DNA sequences. The vector also includes a thymidine kinase (tk) negative-selectable marker gene. Following transfection into ES cells, the PCR-based targeting vector undergoes efficient homologous recombination into the NOS2 locus. Thus, PCR-based gene targeting can be a valuable alternative to the conventional cloning approach. It expedites the acquisition of homologous genomic DNA sequences and simplifies the construction of targeting plasmids by making use of defined cloning sites. This approach should result in substantial time and cost savings for appropriate homologous recombination projects.     

Phylogenetic analysis of cytochromeb sequences in the dasyurid marsupial subfamily phascogalinae: Systematics and the evolution of reproductive strategies

We report DNA sequence variation in 861 bp of the mitochondrial cytochromeb gene from 10 species of the dasyurid marsupial subfamily Phascogalinae (including the New Guinean genusMurexia) and an outgroup planigale (Planigale ingrami). Phylogenetic analyses of these sequences indicate that (1) the subfamily consists of three major clades corresponding to (a)Phascogale, (b) AustralianAntechinus, and (c) New Guinean Antechinus andMurexia; (2) Antechinus habbema constitutes the earliest branch of the New Guinean clade; and (3); Antechinus melanurus and A. naso are sister species within the New Guinean clade. Among Australian antechnuses,A. stuartii andA. swainsonii are more closely related to each other than either is toA. flavipes, a result that is seemingly at odds with all previous systematic studies. Although resolution is limited, it appears thatAntechnius andMurexia species form a clade to the exclusion ofPhascogale. This relationship suggests that male semelparity is not a strong synapomorphy for Australian antechinuses and phascogales, despite its apparent physiological similarity in the two groups.To whom correspondence should be addressed.     

β-Sheet Models for the Ordered Filamentous Structure Formed by a Peptide That Enhances the Action of Insulin

Certain peptides with sequences related to part of the major histocompatibility complex class I antigen enhance the action of insulin. These peptides also aggregate into fibrous structures that seem to be related to their biological activity. In the current study, the 17-residue peptide with amino acid sequence Gly-Asn-Glu-Gln-Ser-Phe-Arg-Val-Asp-Leu-Arg-Thr-Leu-Leu-Arg-Tyr-Ala is used as a representative example of these bioactive molecules. As seen by electron microscopy, the peptide associates into gently twisted ribbons, 50 Å thick, in which the amount of twist decreases as the ribbons become wider. X-ray diffraction analysis suggests that the peptides are arranged as in an antiparallel β-sheet extending essentially endlessly along the fiber axis. The amino acid sequence of the peptide is such that one side of the β-sheet is predominantly polar while the opposite side is nonpolar. This allows the β-sheets to form multilayers with alternating hydrophobic and hydrophilic interfaces. The length of the extended peptide (≈54 Å) determines the thickness of the ribbon and the tendency of individual β-sheets to twist accounts for the twisting of the ribbons. An alternative model is also discussed, again based on antiparallel β-sheets, but with adjacent sheets interdigitated in a “side-by-side” fashion rather than forming stacked layers. Comparable inactive peptides such as Gly-Asn-Glu-Gln-Ser- A_l_a_-Arg-Val-Asp-Leu-Arg-Thr-Leu-Leu-Arg-Tyr-T_y_r_ (changed amino acids underlined) do not form ordered filamentous structures.     

Characterization and analysis of simple sequence repeat (SSR) loci in seashore paspalum (Paspalum vaginatum Swartz)

A size-fractionated TaqI genomic library of seashore paspalum (Paspalum vaginatum Swartz) was screened for the presence of (GA) _n and (CA) _n simple sequence repeats (SSRs). A total of 54 clones with a positive signal were detected among 13,000 clones screened. Forty-seven clones having repeats of n 3 were identified, of which 85% were perfect, 13% were imperfect and 2% were compound repeat sequences. Five of ten primer pairs synthesized to amplify selected loci resulted in a product in the expected size range and were subsequently used to examine SSR polymorphisms among 46 ecotypes of P. vaginatum. The number of alleles resolved on agarose or polyacrylamide gels were similar and ranged from 6 to 16 with an average of 14 per locus. Phenetic analysis of SSR polymorphisms revealed genetic relationships among the P. vaginatum ecotypes that were in general agreement with relationships determined previously by RAPD analysis of the same plant materials. Further screening of the genomic library did not identify (AT) _n , trimeric or tetrameric repeats. Hybridization of an (ATT)₈ oligonucleotide probe to genomic DNA isolated from I. batatas, E. coli, Citrullis lanatus and P. vaginatum suggested that the P. vaginatum genome contained significantly fewer ATT repeats than either the I. batatas or C. lanatus genome.