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A wide range of 2-pyridyl and other difficult-to-access heterocyclic N-methyliminodiacetic acid boronates can be readily prepared from the corresponding bromides via a new method involving direct transligation of 2-heterocyclic trialkoxyborate salts with N-methyliminodiacetic acid (MIDA) at elevated temperatures.

Aims: The purpose of this study was to determine if biomechanical muscle stimulation (BMS) applied directly to different segments of the body using the Swisswing device results in acute improvements in range of motion and perceived stiffness in physically active adults with acute or subacute ankle sprain and hamstring strain injuries., Methods: Two separate groups of individuals with grade I or II ankle sprain (n = 5; 21.2 +/- 1.9 years) or hamstring strain (Nn= 5; 20.6 +/- 1.8 year) underwent 20 minutes of a controlled therapy consisting of ice, compression, and elevation, and 10 minutes of segmental BMS using the Swisswing at 20 Hz. Ankle (dorsiflexion, plantar flexion, inversion, eversion), hamstring flexibility, and subjective ratings of stiffness were assessed prior to control treatment (baseline), post-control treatment, and post-Swisswing treatment., Results: Relative to the post-control condition, Swisswing treatment significantly (P < 0.03 for all) increased ankle dorsiflexion and eversion and hamstring flexibility, and significantly (P

Many boronic acids, including 2-heterocyclic, vinyl, and cyclopropyl derivatives, are inherently unstable, which can limit their benchtop storage and/or efficient cross-coupling. We herein report the first general solution to this problem: in situ slow release of unstable boronic acids from the corresponding air-stable MIDA boronates. This remarkably general approach has transformed all three classes of these unstable boronic acids into shelf-stable and highly effective building blocks for cross-coupling with a wide range of aryl and heteroaryl chlorides.

Fibroblast chemotaxis is implicated in many physiological processes, including wound healing and morphogenesis. We present a novel assay for chemotaxis of fibroblasts (and other slow-moving tissue cells) in a direct-viewing chamber containing a physiologically relevant three-dimensional fibrin or collagen gel in which long-lasting, spatially continuous gradients have been sustained for at least 24 h, long enough for significant fibroblast migration. This combination of features is not available in any alternative assay of comparable setup simplicity. Using a putative fibroblast chemotactic factor, the fibronectin peptide GRGDSP, we measured human foreskin fibroblast alignment in the direction along the gradient, which followed a biphasic dependence on GRGDSP concentration with an optimal concentration of about 10 nM. Time-lapse video microscopy revealed that cell migration was up the soluble GRGDSP gradient, confirming positive chemotaxis to GRGDSP and rejecting the possibility of dominant haptotaxis down the soluble GRGDSP gradient, that is, up a putative gradient of integrin-mediated adhesion induced by the soluble GRGDSP gradient., (Copyright 1999 Academic Press.)

In order to identify structures in human skin that bind collagenase, sections from frozen or paraffin-embedded skin were incubated with either procollagenase or activated collagenase. After washing, bound procollagenase or collagenase was detected by immunofluorescence microscopy. In normal skin, procollagenase bound only to isolated granular dermal cells that were identified as mast cells on the basis of staining with fluoresceinated avidin and pinacyanol erythrosinate. When mast cells were degranulated by exposure to the ionophore A23187, extracellular granules bound procollagenase. Of various pathologic conditions examined, the highest binding of procollagenase occurred in specimens of urticaria pigmentosa. Procollagenase bound to granular cells and to abundant granules scattered throughout the dermis. Binding could be abolished by pre-treatment of tissue sections with heparinase or by pre-incubation of procollagenase with soluble heparin, suggesting that heparin is the binding agent in the granules. Activated collagenase also bound to dermal mast cells but in addition bound strongly to the dermal collagen. Enzymatic activity of activated collagenase was not inhibited by heparin in concentrations up to 10 mg/ml. There is evidence that mast cell tryptase can contribute to procollagenase activation. This study further supports a role for mast cells in collagenolysis by demonstrating that heparin from mast cells binds procollagenase and possibly serves as a reservoir for procollagenase, which may then subsequently be activated.

Effects of supplemental prilled long-chain fatty acids on lactation performance during heat stress were examined using eight multiparous Holstein cows in a replicated 4 x 4 Latin square design with 15-d periods. Cows were ruminally cannulated and were assigned randomly to one of four treatments in a 2 x 2 factorial arrangement of treatments. Factors were 0 or 5% supplemental fat and thermoneutral or heat stress conditions. Cows were housed in environmental chambers with thermoneutral conditions of 20.5 degrees C and 38% relative humidity for 24 h/d or heat stress conditions of 31.8 degrees C and 56% relative humidity for 14 h/d and 25.9 degrees C with 56% relative humidity for 10 h/d. Isonitrogenous diets (17% CP) containing 50% alfalfa silage and 50% concentrate were offered for ad libitum intake. Diets contained 1.64 or 1.83 Mcal NEL/kg DM. No diet by environment interactions were significant. Milk fat percentage (3.46 vs. 3.15%) and 3.5% FCM (31.5 vs. 29.2 kg/d) were higher for cows fed 5 vs. 0% fat. Dry matter intake, milk yield, and milk protein percentage did not differ between diets. Heat stress decreased DMI, milk yield, 3.5% FCM, and milk protein percentage but did not affect milk fat percentage. Results suggest that supplemental fat at 5% of diet DM enhances lactation performance similarly under thermoneutral and heat stress conditions.

Twenty-four Holstein cows, including four primiparous and four ruminally cannulated, were in replicated 4 x 4 Latin squares with 21-d periods to determine the effects of feeding level of whole roasted soybeans on lactation performance and rumen function. Cows were fed rations containing a 50:50 forage:concentrate ratio with 0, 12, 18, or 24% of diet DM as whole roasted soybeans. Rations contained 16.8, 16.9, 18.6, and 19.7% CP and 1.68, 1.71, 1.72, and 1.74 Mcal NEL/kg DM, respectively. Milk production and milk fat percentages for diets containing 0, 12, 18, or 24% whole roasted soybeans were 34.9, 37.5, 38.5, and 38.8 kg/d and 3.23, 3.20, 3.32, and 3.37%, respectively. Milk protein percentage was depressed at all levels of whole roasted soybeans. Ruminal pH, VFA molar percentages except valerate, and DM disappearance of forage from dacron bags did not differ among treatments. Responses were similar among primiparous and multiparous cows. Results suggest benefit from feeding whole roasted soybeans at levels up to 18% of ration DM without adversely affecting DMI, milk fat, or rumen fermentation.