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BACKGROUND: National Nutritional Standards for school lunches were reintroduced in 2001, and included guidance on portion sizes for primary schools. For the first time since 1997, nationally representative data on school food portion sizes in England have been collected using direct assessment rather than reported portion sizes. METHODS: Food portions were weighed directly in foods served in nationally representative samples of primary and secondary school meals. Results were grouped by food or food group. RESULTS: The number of portions weighed was 7975 in primary schools and 3354 in secondary schools. Individual portion weights were grouped by food or food group to yield mean, median, SD and inter-quartile range. For a given food or food group, the number of portions weighed varied from 5 to 210 portions in primary schools and between 5 and 194 portions in secondary schools. CONCLUSIONS: The results provide a good representation of typical portion weights for different foods and food groups in primary and secondary schools in England. Portion size is one factor that determines nutrient intake. New standards for school lunches are both nutrient and food-based. Guidance on portion weights will help to ensure that pupils consume the correct balance of foods to obtain the recommended nutrient intake. The present findings complement and extend existing guidance on portion sizes for pupils in schools in England and Scotland.

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AIM: To describe a new form for collecting problem oriented, problem linked data from primary care. METHOD: A novel form is described which has been used to collect these data. These data were validated against secondary data collections. RESULTS: The form has been used to record 10,937 encounters in a variety of primary care settings. The form was acceptable to general practitioners (GPs) and was completed on 87% of eligible patients in a one week data collection. Data captured provide descriptive data about the problems encountered and services provided during the consultation. These elements of the medical record are linked so that it is possible to address questions about patterns of service provision. Uncomplicated lower urinary tract infection is used as an example of how data from the form can be used to examine clinical practice and resource utilisation. CONCLUSION: A method has been demonstrated to collect problem oriented, problem linked data which may be used for clinical costing and to demonstrate compliance with clinical practice guidelines.

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AIM: General practitioners in the central Sydney area were surveyed to quantify the extent of, and attitudes towards, computerisation in Australian general practice. METHOD: Two surveys were mailed to all GPs in the central Sydney area, first in 1994, and again in 1996. The majority of questions in both surveys were identical. The results were collated and descriptive and comparative statistics calculated. RESULTS: There was an increase in the use of computers for clinical tasks and, GPs' attitudes towards computerised prescribing systems became more positive. There was a persistent negative attitude towards the actual costs of computerisation. CONCLUSION: Methods are now required to transform the increased use of computers by GPs into improved outcomes for them and their patients.

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The objective of this article was to evaluate the Gabrieli Medical Nomenclature (GMN) as a coding system for primary care, using a system of five criteria. These were: the infrastructure supporting the coding system; the code structure; ease of use of the codes; the reproducibility of coding; the usefulness of the codes to Australian GPs. The performance of the GMN was evaluated as being at, or below the level of other coding systems in each of the assessment areas. It was found that the GMN has no advantages over other, existing coding systems. Evaluation of coding systems should include an assessment of the reproducibility of coding and its usefulness to Australian general practice.

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A series of experiments investigated the behavioral and hedonic effects of the synthetic cannabinoid CP 55,940 in male Wistar rats. CP 55,940 had a biphasic effect on locomotor activity, with a 10 micrograms/kg dose causing locomotor stimulation and a 100 micrograms/kg dose causing profound hypoactivity. CP 55,940 (100 micrograms/kg) also caused a marked hypothermia for at least 3 h following administration, while lower doses (2.5 and 10 micrograms/kg) had no effect. CP 55,940 (100 micrograms/kg) had anorexic and hyperdipsic effects for up to 24 h following administration and caused significant reductions in body weight. CP 55,940 (100 micrograms/kg) also caused significant avoidance to a flavoured fluid (saccharin) with which it was paired. In the conditioned place preference paradigm both the 10 micrograms/kg and 100 micrograms/kg doses of CP 55,940 produced significant place avoidance. It is concluded that CP 55,940 is aversive to rats. The possible mechanisms underlying this aversion are discussed.

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Applications for a new polymer resin, PolyFlo, are described for both the small-scale and large-scale purification of synthetic oligodeoxyribonucleotides varying in length from 18-41 bases. The unique properties of this innovative resin provide > 95% purified full-length oligodeoxyribonucleotides with greater than 90% yield starting from either crude trityl-on or trityl-off unmodified as well as base (biotin)- or backbone (e.g., phosphorothioate)-modified products. Full biological activity of recovered nucleic acid is retained, and the resin is capable of removing contaminating endotoxins during purification. The resin performance is predictable and reliable. The resin can be regenerated easily and is particularly economic when employed directly in ammonia or with the trityl-off option. PolyFlo meets the requirements of current Good Manufacturing Practices.

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While studying cAMP-dependent dynein alpha-heavy chain phosphorylation, we found previously [Stephens and Prior, 1992: J. Cell Sci. 103:999-1012] that high salt extraction of sperm flagella from the mussel Mytilus edulis or the clam Spisula solidissima removed most visible dynein arms, accompanied by an amount of Mg+2-ATPase that correlated with the mass of dynein alpha- and beta-heavy chains removed. However, although almost devoid of ATPase activity, such extracted axonemes retained one third of the heavy chain mass as two sets of electrophoretically-distinct, vanadate-cleavable, non-phosphorylated proteins. To explore the nature of these dynein-like proteins, antibodies to the alpha- and beta-heavy chains were blot affinity-purified from a rabbit antiserum raised against gradient-purified Spisula 18-20S flagellar outer arm dynein. Although able to recognize common epitopes of the opposite chain type, neither the alpha- nor the beta-heavy chain antibody recognized the tightly-bound proteins in either species, proving that they are immunologically distinct. While the beta-antibody recognized its heavy chain homolog in gill cilia, the alpha-antibody did not, demonstrating immunological distinction between flagellar and ciliary dynein alpha-heavy chains. Immunization of a mouse with nitrocellulose strips containing one of the two tightly-bound Spisula flagellar proteins produced an antiserum that cross-reacted with each tightly-bound protein in both species and also recognized alpha- and beta-heavy chains. The anti-molluscan serum cross-reacted strongly with sea urchin sperm flagellar dynein B-, C-, and D-bands, considered to be inner arm components, but not with sea urchin outer arm alpha- or beta-heavy chains. These data indicate that the electrophoretically and immunologically distinct, tightly-bound proteins of molluscan flagella are inner arm dynein heavy chains.

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Serotonin, an activator of adenylate cyclase, stimulates motility in molluscan gill cilia and sperm flagella. To determine and compare potential targets of cAMP action, dynein was prepared from the lateral gill.cilia and sperm flagella of the mussel Mytilus edulis and the clam Spisula solidissima. In the flagella of both species, high-salt extraction removes about half of the ATPase activity, half of the alpha and beta heavy chains, and the outer arms. The dynein from both species sediments at 18-20 S, contains two or three intermediate chains, and three light chains. High-salt plus detergent removes most of the remaining dynein ATPase, alpha and beta heavy chains, and inner arms, also yielding a stable 18-20 S particle. In gill cilia of both species, high-salt extraction removes only 12-18% of the ATPase, up to 1/3 of the alpha heavy chains, an equivalent amount of beta heavy chain, and a subset of the outer arms. The dynein sediments at 18-20 S and, in Spisula, the heavy, intermediate, and light chains precisely co-sediment. High-salt plus detergent removes another 1/3 of the alpha heavy chains, an equivalent amount of beta heavy chain, and the remaining outer arms. The ATPase sediments mainly as a 13-14 S form showing considerable dissociation of co-sedimenting intermediate and light chains. The inner arms and at least half of the ciliary dynein ATPase activity remain unextractable, corresponding in mass mainly to an apparent beta heavy chain that is vanadate-cleavable. Cyclic AMP-dependent, calcium-independent phosphorylation takes place on specific dynein light chains in cilia but on only the dynein alpha heavy chain in flagella. Pre-activation of the flagella prevents subsequent addition of labeled phosphate. Phosphorylation has no effect on the steady-state ATPase properties. The single phosphate added to the flagellar alpha chain is located within the LUV1 vanadate photocleavage fragment. Considering the probable locus of the light chains and the site of the alpha heavy chain phosphorylation, both beyond the active site and toward the base of the molecule, these distinct phosphorylations may regulate dynein action by modulating arm flexibility or interaction.

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The 5' flanking region of the rabbit myosin heavy chain (HC) beta gene extending 295 bp upstream from the cap site provides muscle-specific transcriptional activity. In this study, we have identified and functionally characterized cis-acting elements that regulate the muscle-specific expression within this region. By using linker-scanner (LS) mutants between -295 bp and a putative TATA box, we found five distinct positive cis-acting sequences necessary for transcription: element A, the sequences between -276 and -263, which contains a putative M-CAT motif in an inverted orientation; B, the sequences between -207 and -180; C, the sequences between -136 and -127; D, the sequences between -91 and -80; and E, a TATA consensus sequence at -28. The fragment containing both A and B elements dramatically enhanced the expression of the chloramphenicol acetyltransferase (CAT) gene driven by a heterologous promoter in differentiated muscle cells, whereas fragments containing either A or B elements alone had little or no effect in either muscle or nonmuscle cells. Therefore, these two elements appear to act cooperatively in determining a high level of muscle- and stage-specific expression. Unlike the typical enhancer element, this region functions in an orientation-dependent manner. In contrast, the fragment containing C and D elements activates the heterologous promoter in both muscle and nonmuscle cells in an orientation-independent manner.

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Overload hypertrophy of the chicken anterior latissimus dorsi muscle is accompanied by a replacement of one myosin isoenzyme (slow myosin-1, SM1) by another (slow myosin-2, SM2). To investigate the molecular mechanisms by which these changes occur, we measured the fractional synthesis rates (ks) in vivo of individual myosin-heavy-chain isoenzymes, total actin and total protein during the first 72 h of muscle growth. Although the ks of total protein and actin were doubled at 24 h, the ks for SM1 and SM2 were depressed. However, the ks of both isomyosins were nearly tripled by 72 h. Despite the increase in muscle size observed at 72 h, the amount of SM1 was reduced by half, indicating increased degradation of SM1. Results of translation of polyribosomes in vitro paralleled the results obtained in vivo. The proportion of total polyadenylylated mRNA in total RNA was increased at 48 and 72 h, but unchanged at 24 h despite the increase in protein synthesis at 24 h. Nuclease-protection analyses indicate that the level of specific SM1 and SM2 mRNAs change in a reciprocal fashion during overload. We conclude that gene-specific and temporal differences exist in the regulatory mechanisms that control overload-induced muscle growth.

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The impact of continuous perfusion cell culture technology on production of one and two chain human rtPA, as well as monoclonal IgG and IgM, will be reviewed. Perfusion as compared to batch systems improve the quality of the product in the conditioned media in terms of biological activity and structural integrity. This significantly increases downstream recovery and daily production output of final purified material. These findings are a consequence of the ability of perfusion technology to 1) maintain cells intact at high cell density; 2) effectively reduce serum content to approximate serum free conditions; and 3) minimize residency time of labile product within the 37 degrees C environment of the bioreactor.

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Number and affinity of thromboxane A2/PGH2 receptors on gel-filtered human platelets was determined using the receptor antagonist 3H-SQ 29548 as a tracer compound. Preincubation of platelet rich plasma (PRP) with U 46619 reduced receptor number to 31% of control platelets without affecting the affinity (2 x 10(-9) mol/l). Pretreated platelets lost their reactivity to stimulation by U 46619 but not to thrombin within 3 h. It is concluded that preincubation of platelets leads to a homologeous platelet desensitisation and down regulation of thromboxane receptors.

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The structural similarities of the heavy chains (HC) of myosin isolated from atria and ventricles of hyper-, hypo-, and euthyroid rabbits were compared by immunological analysis, by one- and two-dimensional peptide mapping, and by electrophoresis under nondenaturing conditions. Monoclonal and polyclonal antibodies, which are specific for HC alpha of ventricular myosin, cross-reacted equally with the HCs of euthyroid atrial myosin. Our immunological analysis identified multiple epitopes common to euthyroid atrial HC and ventricular HC alpha. One- and two-dimensional gel electrophoretic analysis of peptides produced by partial proteolytic digestion of each type of HC reveal no differences between euthyroid atrial HCs and ventricular HC alpha, whereas marked differences are apparent between atrial HC and ventricular HC beta. Nondenaturing gel electrophoresis separates ventricular myosin from hyper- and hypothyroid rabbits into two forms, V1 and V3, respectively. In euthyroid atria, two isomyosins, A1 and A2, were resolved; with the slower moving A2 isomyosin having the same mobility as that of the V1 isomyosin. After cross-hybridization of light chains of ventricular myosin with euthyroid atrial HCs, only a single band having a mobility identical with that of the V1 isomyosin was seen. Furthermore, atrial myosin HCs isolated from hyper- and hypothyroid rabbits were indistinguishable from euthyroid atrial HC and from ventricular HC alpha by these procedures. We conclude that ventricular HC alpha and atrial HC are indistinguishable proteins, and that the type of HC expressed in the atria is unaffected by the thyroid state of the rabbit.

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The amount of myosin per gram of cardiac and skeletal muscle was determined in sodium dodecyl sulfate-solubilized tissue homogenates by radioimmunoassay and by isotope dilution. In the rabbit ventricle, there was an average of 27 mg myosin/g wet wt of tissue. In chickens, the myosin content of typical "red" (anterior latissimus dorsi) and "white" (posterior latissimus dorsi) skeletal muscles was higher than that of ventricular muscle, averaging 36 and 48 mg/g of tissue, respectively. The stoichiometry of the heavy and light chains in cardiac myosin was also determined from the quantitative binding of 125I-labeled Coomassie blue to each subunit after separation of the subunits by sodium dodecyl sulfate-gel electrophoresis. With this procedure, we found that the combined light-chain subunits contributed 19% of the myosin mass. After adjustment for the light-chain contribution, the myosin heavy-chain content of the rabbit ventricle averaged 22 mg/g wet wt of tissue.

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The incorporation rate of [3H]leucine into cardiac myosin subunits was studied in rat hearts undergoing hypertrophy secondary to constriction of the ascending aorta. Cardiac myosin was prepared by a modified Shiverick's method on the second and fourth day after constriction. Myosin light chains were separated by urea and subjected to two-dimensional electrophoresis. Incorporation of [3H]leucine was determined in electrophoretically separated heavy and light chains by the method of Martin et al. (11). It was found that the incorporation rate of [3H]leucine into the phosphorylated form of the myosin light chain 2 is significantly increased in hypertrophic heart as compared to sham animals.

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By 30min continuous infusion of [3H]leucine into rats, the specific radioactivities of plasma leucine and tissue-free and tRNA-bound leucine in heart were equal. The specific radioactivity of leucyl-tRNA in heart therefore follows a time course identical with that of plasma leucine soon after the start of infusion. The half-life of cardiac myosin heavy chain (5.5 days) was the same as that reported by other investigators who used the pulse-labelling protocol.

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