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Br J Sports Med 2004;38:210-213. doi: 10.1136/bjsm.2002.003277 Objective: To determine if the combined isometric contractions of knee extension/hip adduction and knee extension/hip abduction will elicit a different quadriceps and gluteus [...]

A series of novel, disulfide-constrained human β-melanocyte stimulating hormone (β-MSH)-derived peptides were optimized for in vitro melanocortin-4 receptor (MC-4R) binding affinity, agonist efficacy, and selectivity. The most promising of these, analogue 18, was further studied in vivo using chronic rat food intake and body weight models.

Two strains of Schistosoma mansoni were used to investigate the hereditary basis of species-specific host recognition by analysing behavioural responses of miracidia to snail-conditioned water. An Egyptian strain of S. mansoni, capable of distinguishing its host snail Biomphalaria alexandrina from other snails was cycled repeatedly through Biomphalaria glabrata, the intermediate host of a Brazilian strain known to respond even to non-susceptible snails with high intensity. After 5 cycles in the non-natural host, miracidia of the Egyptian strain still retained their preference for the original host snail. In a second experiment, host-finding behaviour of hybrids between these two parasite strains was studied. In the F1 generation, hybrids of both parental combinations showed the same low degree of specificity as the pure-bred Brazilian strain. Approximately one quarter of F2 hybrids proved to be as discriminatory as the Egyptian strain, confirming dominant Mendelian inheritance of non-specificity in schistosome miracidial host-finding behaviour. Moreover, hybrids seem to have lost the ability to develop in B. alexandrina, possibly suggesting a link between host recognition and host compatibility. The heredity of this behavioural trait is of evolutionary and epidemiological significance, since a shift to low host-finding specificity might have been a prerequisite for S. mansoni to acquire new host snails after being introduced to South America by the slave trade.

Echinostome larval stages in the snail have a great potential as effective competitors for the control of schistosomes and adult worms can cause painful intestinal diseases in humans. Ecology and transmission of the larval stages of trematodes are poorly understood, especially because their identification in field-collected samples by microscopy is difficult. We cloned, sequenced and analysed a 192 bp tandem repreated DNA sequence of Echinostoma caproni (EcSau3A), an often discussed antagonist of Schistosoma mansoni in Biomphalaria snails. PCR primers against this sequence can detect less than 10 fg of E. caproni DNA, 2 miracidia in snails 1 day p.i., 1 metacercaria in 50 mg snail tissue and 1 cercaria in 50 mg plankton with high specificity. Methods described in this study can support the discovery of fundamental ecological principles on distribution, host specificity and epidemiology of E. caproni larvae under field conditions.

A new method of separation of single polyprenols (or dolichols) from a mixture of isoprenoid alcohols is described. Application of a high-performance liquid chromatography (HPLC) apparatus equipped with a semipreparative ODS column resulted in preparation of long-chain (dihydro)polyprenols of high purity (>95%).This approach substantially decreases the time scale of the conventional chromatographical preparative procedure. The method can be widely used in chemical and biochemical projects, where single polyprenols or dolichols are required.

The snail host signals releasing host-finding responses in miracidia and cercariae of Echinostoma caproni were analysed by fractionation of snail-conditioned water (SCW). Cercariae responded non-specifically to organic and hydrophilic, low molecular weight components of SCW showing their typical turning response. Hydrolysis of peptides in SCW had no effect on cercarial responses. An artificial mixture of amino acids in concentrations determined from SCW as well as glycine alone in a concentration corresponding to the total concentration of amino acids in SCW showed nearly the same efficacy as SCW itself. Miracidia responded to a high molecular weight glycoprotein fraction, which could be isolated from SCW by ion-exchange and size-exclusion chromatography. In contrast to an Egyptian Schistosoma mansoni strain, the echinostome miracidia were not able to differentiate between different snail species. The results show for the first time that miracidia and cercariae of the same species may use different signals to identify the same snail host species. This indicates an independent evolution of host-finding mechanisms in the two parasite stages.

Three low lignin, brown midrib (bmr) sorghum (Sorghum bicolorL. Moench) mutants, designated bmr‐6, bmr‐12, and bmr‐18, were each backcrossed to normal grain‐ and grassy‐type sorghums. The objective was to determine if the effect of the brown midrib mutants on fiber composition would be expressed equally in both grain‐ and grassy‐type genetic backgrounds. Analysis for fiber composition and in vitro dry matter disappearance (IVDMD) was conducted on mature stem tissue of mutant and normal plants from the F2generation Of the first and second backcross. The bmr‐6 mutant reduced lignin percentage from 10.3 to 8.5 (P < 0.01) and increased IVDMD percentage from 39.6 to 48.7 (P < 0.01). Mutant ✕ background and mutant backcross interactions were not significant (P > 0.10), indicating that the effect of the bmr‐6 mutant was expressed as well in grassy‐type as in grain‐type backgrounds. Similar results were obtained with the bmr‐12 and bmr‐18 mutants. These mutants, evaluated after only one backcross, reduced stem lignin from 8.3 to 6.1% (P < 0.01) and increased IVDMD from 44.0 to 55.5% (P < 0.01). The effects were expressed as well in grassy‐type as in grain‐type backgrounds. Results indicate that sudangrass sorghums containing brown midrib mutant genes are lower in lignin percentage and higher in digestibility than normal genotypes. Mutant sudangrasses of this nature should be higher in digestible energy percentage and should result in greater animal production than normal sudangrasses [Sorghum sudanense(Piper) Stapf] when fed to ruminant animals.

Ammoniation of tall fescue hay (Festuca arundinacea Schreb.) at 30 g/kg hay increased dry matter digestion from 39.4 to 57.4%. Hemicellulose and cellulose digestion coefficients were increased from 57.4 to 92.0% and from 50.0 to 71.6%, respectively. Ammoniation decreased the concentration of hemicellulose in the hay by 5.2 percentage units and increased the total N from 1.27 to 2.67%. Ammoniation increased (P<.05) ad libitum hay consumption by 32% when fed to lambs and by 52% when fed to cattle. Ammonia concentration in the rumen of animals consuming ammoniated hay did not exceed 12 mg/100 ml rumen fluid. Infrared spectral characteristics of the treated and untreated hays indicated that ammoniation significantly reduced ester bond absorbance and increased amide bond absorbance in the fiber fraction of the hay. These changes in infrared absorbance properties presumably resulted from the breaking of ester bonds through ammonolysis. The breaking of ester bonds between lignin and structural carbohydrates may have been primarily responsible for the greater fiber digestibility of the ammoniated hay.

Chronological age is a common basis of reference used in bermudagrass research treatments and forage production management recommendations. Plant growth and development changes due to the environment could cause a confounding of research results when assuming that forage of a given chronological age has a similar nutritive value regardless of the season or year. This field study on victoria clay soil (a Typic Pellusterts) was conducted to measure the mouth‐to‐mouth variation in quality of Coastal and Coastcross‐1 varieties of bermudagrass (Cynodon dactylon, (L.) Pers.) harvested at 4, 8, 12, 16, 20, and 24 week growth intervals through the 1975 growing season, Samples were taken from March through December. Acid detergent fiber (ADF), neutral detergent fiber (NDF), crude protein (CP), and in vitro dry matter digestibilit (IVDMD) were measured. Statistical comparisons or quality were made only within age intervals. Fifty percent of 312 month‐to‐month comparisons were significantly different. Coastcross‐1 bermudagrass was more variable than Coastal bermudagrass, because of greater declines as well as greater increases in quality due to environmental changes. The 8‐week‐old forage had the greatest variation in quality in both varieties. The most measurable variability was in crude protein content. Month‐to‐month variability of CP declined with advancing maturity in Coastal and increased in Coastcross‐1. Variation as measured by ADF and IVDMD was second and third to CP, respectively, and the grassa responded similarly. Overall variability measured by NDF was the lowest of the four methods used. Actual percentage changes in ADF, NDF, CP, and IVDMD of 8‐week‐old forage within a 30day period was as high as 9.9, 3.0, 4.6, and 12.7 percentage units, respectively, for Coastcross‐1. The impact of environmental conditions on forage quality was significant and was dependent up on the age of the grass, the specific quality component in question, and the grass variety. Therefore, care should be exercised in extrapolating research data from one season of the year to another even at the same geographical location.

If the conclusions which Kondo et al. [1] obtained by testing a large number of photographic lenses (35 mm cameras) are combined with the quality number suggested by Heynacher [2] a very simple method of describing the photographic image quality is achieved. This method, its origin, and some results are discussed.

Abstract: Mode launching on a symmetrical multimode slab-waveguide by a plane wave incident onto the front side of the guide is investigated theoretically and experimentally. A single plane wave always excites a whole set of modes. Among these are, in general, three adjacent modesm-1, m, m+1 which are excited most strongly. The relative power launched into these modes is approximately given by the ratio 0.4:1:0.4. The theoretical results are confirmed by qualitative observations of the far-field mode patterns. In the far field the modes are separated by using a wedge-type waveguide.

Im Zusammenhang mit der Anwendung von elektronischen Analogrechnern zur Lösung von Problemen der angewandten Optik werden die mathematischen Beziehungen wichtiger Bestimmungsgrössen der optischen Abbildung in einem Diagramm dargestellt. Der Übergang von der komplexen Pupillenfunktion zur Lichterregung im Punktbild wird für den rotations-symmetrischen Fall genauer behandelt und die dafür verwendete Analogrechenschaltung beschrieben. Den Abschluss bilden einige Beispiele, die mit dem Analogrechner behandelt wurden.

It is shown that the effective mass and its directional dependence can be determined from the rotation of the reflected linear polarized light under the influence of a magnetic field (Faraday-Effect in reflection). This method was applied to hexagonal single crystals of Selenium. For the effective mass, a value of about 10m0 was obtained in the upper branch of the valence-band, in the lower branch a value of about 1m0 was obtained (m0=rest mass of the electron).

In this study 13 women bathed in a warm tub bath during the first stage labor after a strictly normal pregnancy. The control group consisted of 9 women who did not want warm tub bath. Apgar scores at 1 and 5 minutes were recorded and plasma adrenalin, noradrenalin were measured in umbilical arterial blood at birth, together with pH, pCO2, and base excess and beta-endorphin-like immunoreactivity in umbilical venous blood. No differences were found between the groups. No beneficial effect was found on infant condition of a warm tub bath during labor.

Study DesignCross-sectional.ObjectivesTo compare gluteal muscle thickness changes measured by ultrasound imaging (USI) during lateral band walking with the resistance band positioned around the ankles or the forefeet in individuals with a history of lateral ankle sprain (LAS).BackgroundEvidence suggests proximal neuromuscular adaptations exist in individuals with a history of LAS. Understanding how lateral band walking exercises target the proximal musculature could be beneficial for treatment following LAS.Methods and Measures18 individuals (Age=22±6 years, Height=168.8±10.5 cm, Mass=74.4±28.7 kg, Previous LAS=4±3) with history of LAS participated. B-mode USI of gluteus maximus (GMax) and gluteus medius (GMed) were collected during lateral band walking. The 8 MHz wireless transducer was secured to participants using an elastic belt. Patients performed 3 trials of 5 lateral steps per band position. Thickness measures were taken from the inferior aspect of the superior muscle border to the superior aspect of the inferior border of each muscle. Images were normalised to quiet standing. The percent activity beyond quiet standing was calculated by taking the exercise muscle thickness divided by quiet muscle thickness. Paired sample t-tests were used to compare each muscle in each band position. Cohen’s d effect sizes (ES) were calculated to determine magnitude of difference.ResultsThe percent activity for GMax (10.63%±7.01% ankle vs. 13.98%±7.21% forefoot, p=0.009, ES=0.48) and GMed (13.61%±18.60% ankle vs. 19.10%±19.30% forefoot, p<0.001, ES=0.30) increased from the ankle position to forefoot position.ConclusionThe percent activity increased for both muscles in the forefoot position compared to the ankle position. Placing the resistance band around the forefoot may be a more challenging task for individuals with a history of LAS. During rehabilitation, it may be beneficial to begin with lateral band walks around the ankle and progress to the forefoot position as patients become more proficient at the exercise.

Study DesignCohort study.ObjectivesTo investigate whether a clinical test battery conducted within 2 weeks of a first-time lateral ankle sprain (LAS) can be used to predict outcome (Chronic Ankle Instability [CAI] vs LAS ‘coper’) 12 months later.BackgroundNo prospective analysis is currently available which has sought to identify whether clinical assessment tools can be used to predict long-term recovery following a first-time LAS.Methods and MeasuresEighty-two individuals with first-time LAS were assessed using a clinical test battery within two-weeks of incurring a first-time LAS. These participants were classified 12 months later as having CAI or as being LAS ‘copers’ using the Cumberland Ankle Instability Tool (CAIT).Outcome measuresScores on the ‘talar-glide’ (deg), anterior-drawer, talar-tilt, figure-of-eight [figure8] for swelling (m), knee-to-wall (m) and hand-held goniometric range-of-motion [inversion; eversion; plantar-flexion {in degrees}] tests within two weeks of a first-time LAS, and scores on the CAIT 12 months later.ResultsSeventy (85%) of the original 82 injured participants completed the 12 month follow-up. Of the final seventy, 28 (40%) were designated as having CAI with 42 (60%) being designated as LAS copers. A logistic regression analysis revealed that a combined model using scores from the talar-glide, talar-tilt and anterior-drawer tests in addition to plantar-flexion ROM was statistically significant (p<0.01) and correctly classified 68.8% of cases. The final model had a sensitivity of 64% and a specificity of 72%.ConclusionsThis is the first analysis in which the predictive value of a clinical test battery for ankle sprain injury for determining CAI has been investigated. While our results showed that some of these clinical tests demonstrate predictive value, the accuracy at which they identify individuals at risk of developing CAI is moderate. Further research is required to determine whether performing these tests in a less heterogenous sample of individuals (perhaps within 48 hours of injury) would improve their predictive value.

Study DesignDescriptive Laboratory.ObjectivesTo assess change in foot morphology across loading using innovative, clinically accessible 3-dimesional composite measurements of surface area (SA), volume (V), and SA/V ratio in recreationally-active young adults.BackgroundThe foot is quarter-ellipsoid shaped and normally deforms during loading. Foot pliability varies by morphotype and is clinically important when managing foot and ankle pathology. Current clinical composite measures of foot deformation are limited to 2-dimensions.Methods and MeasuresThe feet of 106 recreationally-active young adults (54 right, 52 left, 46 males, 60 females, mean age:21.1±4.2, BMI:24.2±5.0, FPI:4.0±4.0) were evaluated. Foot posture index (FPI) was assessed and categorised as <-1=supinated, 0–5=normal, 6–9=pronated, and ≥10 = highly-pronated. Foot length, width, and height were measured in sitting and bipedal standing and used to calculate the SA and V of a quarter-ellipsoid. SA and V changes characterise foot widening, lengthening, and arch deformation during loading. The SA/V (%) represents changes in both foot size and shape. ANOVAs were performed to compare the effects of foot morphotype and loading on the composite measures. Post-hoc Fisher’s least significant differences (LSD) were calculated for significant interactions.ResultsLoading significantly decreased foot volume across all foot types (mean ±95% CI: supinated:624.4±61.1 cm3to 615.7±58.2 cm3, normal:564.1±29.8 cm3to 556.7±31.3 cm3, pronated:565.7±57.7 cm3to 541.6±57.3 cm3, highly pronated:554.8±76.9 cm3to 539.8±76.5 cm3; p<0.001, η²=0.16). There was a significant loading by morphotype interaction for SA/V measures (mean ±95% CI: supinated:36.6±1.2% to 37.0±1.2%, normal:38.0±0.7% to 38.6±0.7%, pronated: 38.2±1.3% to 39.4±1.4%, highly-pronated: 38.9±2.1% to 39.9±2.4%; p=0.005, η²=0.12, LSD=0.2%). Significant progressive increases in SA/V were observed the more pronated a foot was. No other significant differences were observed for the three composite measures.ConclusionsQuarter-ellipsoid measures calculated from morphologic measurements may have clinical utility in quantifying 3-dimensional foot changes during loading and likely advantageous over 2-dimensional measures when assessing need and response to intervention.

Congenital chylothorax in a male infant persisted for 10 weeks despite repeated thoracocenteses and dietary regimens which included total parenteral nutrition for 37 days and a peroral semielementary diet with medium-chain triglyceride content for 19 days. Thoracotomy disclosed a small leak in the thoracic duct. The duct was ligated above and below the leak, as attempted repair was unsuccessful. There was no recurrence of pleural effusion after the operation and no distal lymphoedema was observed.