1,226 research outputs found

    Effects of unilateral and bilateral squatting on rotational speed in male and female collegiate golfers

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    Resistance training in combination with plyometrics and medicine ball routines has been shown to improve rotational speed and power. One area that has not been observed has been the difference between bilateral squatting and unilateral squatting on rotational speed. The purpose of the study was to observe the effects of unilateral and bilateral squatting on club head speed in collegiate golfers. Eight male and nine female collegiate golfers were randomly assigned to a unilateral squat group which was the experimental and a bilateral squat group which was the control group and participated in twelve training sessions over the course of four weeks. Club head speed measurements were taken prior to the first training session and after the twelfth training session on a Trackman 4 indoor unit. After the intervention, there were no statistically significant improvements in either group and no statistically significant differences between the unilateral group (pre-training = 100.8 mph ± 12.2 mph, post-training = 100.9 mph ± 12.5 mph) and the control group (pre-training = 102.8 mph ± 11.7 mph, post-training = 103.3 mph ± 12.3 mph). Short duration squat training does not appear to positively impact club head speed in collegiate golfers

    Age-dependent production of IgA and IgM autoantibodies against IgG2a in a colony of 129/Sv mice

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    Although much of the basic immunological work has been done with mice, little is known about anti-IgG autoantibodies in this species. Dresser (1, 2) has reported the occurrence, in CBA mice, of anti-IgG antibody (Ab)(1) detected by a hemolytic-plaque assay after stimulation with endotoxin or immunization against sheep erythrocytes. IgM rheumatoid factor has also been described in various strains of mice with a systemic lupus erythematosus-like disease (3). Recently, we have tried to induce anti-IgG in mice of the 129/Sv strain by inoculating autologous IgG. To our surprise, we found that the sera of all the animals had, before any inoculation, anti-IgG detectable by agglutination of particles coated with autologous IgG. The possibilities to investigate the mechanism of production and the biological role of this kind of Ab prompted us to undertake a study of the nature and specificity of the mouse anti-IgG

    Monoclonal anti-IgG autoantibodies derived from lipopolysaccharide-activated spleen cells of 129/Sv mice

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    In some colonies, 129/Sv mice produce, upon aging, a rheumatoid factor (RF) that is specific for mouse IgG2a but fails to react with IgG2a of the b allotype. It is not known whether this narrow specificity is due to the absence of other RF specificities in the repertoire of these mice or to the selective activation of the production of anti-IgG2a autoantibodies by a specific stimulus. To analyze the RF repertoire of 129/Sv mice, we have derived hybridomas from their spleen cells 3 d after an intraperitoneal injection of lipopolysaccharide. We have obtained 68 hybridomas secreting a monoclonal IgM with RF activity. This represents approximately 3 percent of the total number of hybridomas generated in four hybridizations. In addition, one monoclonal IgA RF was derived from unstimulated 129/Sv spleen cells. The specificities of these monoclonal RF were examined by testing their ability to bind to a panel of homologous and heterologous IgG preparations. The majority of the IgM RF reacted exclusively with a single mouse IgG subclass: 58 with IgG1, and 1 with IgG2a. Eight bound preferentially to IgG1 but cross-reacted to some extent with IgG2a and one was specific for a determinant shared by IgG1, IgG2a, and IgG3. The IgA RF derived from unstimulated spleen cells was primarily directed against IgG2a but cross- reacted somewhat with IgG2b. Identical results were obtained with two different monoclonal IgG1 and IgG2a proteins of the a allotype. No allotypic specificity was found for the anti-IgG1 RF, which all reacted well with IgG1 of the b allotype. In contrast, the IgM anti-IgG2a antibody exhibited such allotypic specificity because it failed to react with IgG2a of the b allotype. When tested on heterologous IgG preparations, all anti-IgG1 RF reacted better with rat IgG1, rat IgG2c, bovine IgG2, goat IgG2, and rabbit IgG than with mouse IgG1, demonstrating a particular homology between these Ig. On the basis of additional cross-reactions with other IgG, including rat IgG2a, rat IgG2b, bovine IgG1, goat IgG1, human IgG, and chicken IgG, seven different anti-IgG1 clonotypes could be identified. However, despite their heterogeneity, nearly all antigenic determinants recognized by anti-IgG 1 RF appeared to be located in the hinge region of the molecule. Total lack of binding to IgG1 Fab fragments was indeed observed, and only one antibody reacted with IgG1 Fc fragments. Unlike the anti-IgG1 RF, the IgM and the IgA anti-IgG2a antibodies did not cross-react with any heterologous IgG of the same panel. Altogether, t 1 different RF clonotypes could be distinguished on the basis of their fine specificity. The anti-IgG2a specificity of the RF spontaneously produced by 129/ Sv mice is thus not due to the absence of other RF specificities in the repertoire of these mice

    Continuous direct compression as manufacturing platform for sustained release tablets

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    This study presents a framework for process and product development on a continuous direct compression manufacturing platform. A challenging sustained release formulation with high content of a poorly flowing low density drug was selected. Two HPMC grades were evaluated as matrix former: standard Methocel CR and directly compressible Methocel DC2. The feeding behavior of each formulation component was investigated by deriving feed factor profiles. The maximum feed factor was used to estimate the drive command and depended strongly upon the density of the material. Furthermore, the shape of the feed factor profile allowed definition of a customized refill regime for each material. Inline NIRs was used to estimate the residence time distribution (RTD) in the mixer and monitor blend uniformity. Tablet content and weight variability were determined as additional measures of mixing performance. For Methocel CR, the best axial mixing (i.e. feeder fluctuation dampening) was achieved when an impeller with high number of radial mixing blades operated at low speed. However, the variability in tablet weight and content uniformity deteriorated under this condition. One can therefore conclude that balancing axial mixing with tablet quality is critical for Methocel CR. However, reformulating with the direct compressible Methocel DC2 as matrix former improved tablet quality vastly. Furthermore, both process and product were significantly more robust to changes in process and design variables. This observation underpins the importance of flowability during continuous blending and die-filling. At the compaction stage, blends with Methocel CR showed better tabletability driven by a higher compressibility as the smaller CR particles have a higher bonding area. However, tablets of similar strength were achieved using Methocel DC2 by targeting equal porosity. Compaction pressure impacted tablet properties and dissolution. Hence controlling thickness during continuous manufacturing of sustained release tablets was crucial to ensure reproducible dissolution. (C) 2017 Elsevier B.V. All rights reserved
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