Effectiveness of different footbath solutions in the treatment of digital dermatitis in dairy cows

Three experiments were conducted to test the effectiveness of different footbath solutions and regimens in the treatment of digital dermatitis (DD) in dairy cows. During the study, groups of cows walked through allocated footbath solutions after milking on 4 consecutive occasions. All cows were scored weekly for DD lesion stage on the hind feet during milking. A “transition grade” was assigned on the basis of whether the DD lesions improved (1) or deteriorated or did not improve (0) from week to week. This grade per cow was averaged for all cows in the group. In experiment 1, 118 cows were allocated to 1 of 3 footbath treatments for 5 wk: (1) 5% CuSO4 each week, (2) 2% ClO- each week, or (3) no footbath (control). The mean transition grade, and proportion of cows without DD lesions at the end of the trial were significantly higher for treatment 1 above (0.36, 0.13, and 0.11, respectively; standard error of the difference, SED=0.057). In experiment 2, 117 cows were allocated to 1 of 4 footbath treatment regimens for 8 wk: (1) 5% CuSO4 each week, (2) 2% CuSO4 each week, (3) 5% CuSO4 each fortnight, or (4) 2% CuSO4 each fortnight. For welfare reasons, cows allocated to the weekly and fortnightly footbath regimens had an average prevalence of >60% and =25% active DD at the start of the trial, respectively. Significantly more cows had no DD lesions (0.53 vs. 0.36, respectively; SED=0.049), and the mean transition grade of DD lesions was higher in the 5% compared with the 2% weekly CuSO4 treatment (0.52 vs. 0.38, respectively; SED=0.066). Similarly, significantly more cows had no DD lesions in the 5% compared with the 2% fortnightly CuSO4 treatments (0.64 vs. 0.47, respectively; SED=0.049). In experiment 3, 95 cows were allocated to 1 of 3 footbath treatments: (1) each week alternating 5% CuSO4 with 10% salt water, (2) each week alternating 5% CuSO4 with water, or (3) 5% CuSO4 each fortnight (control). After 10 wk, more cows had no DD in the salt water treatment than in the control treatment (0.35 vs. 0.26, respectively; SED=0.038), but levels of active lesions were higher for this treatment than in the other 2 treatments (0.17, 0.00, and 0.13, respectively; SED=0.029). Treatment did not affect mean transition grade of DD lesions. In conclusion, CuSO4 was the only footbath solution that was consistently effective for treatment of DD. In cases when DD prevalence was high, a footbath each week using 5% CuSO4 was the most effective treatment.

Interactions of the 67 kDa laminin receptor and its precursor with laminin

The 67LR (67 kDa laminin receptor) enables cells to interact with components of the extracellular matrix The molecule is derived from the 37LRP (37 kDa laminin receptor precursor); however, the precise molecular mechanism of this conversion is unknown. Recombinant 37LRP expressed in and purified from Escherichia colt, bound to human laminin in a SPR (surface plasmon resonance) experiment. 67LR isolated from human breast-cancer-derived cells in culture was also shown to bind to laminin by SPR. However, the kinetics of association are qualitatively different. 37LRP but not 67LR, binds to heparan sulfate. The binding of 37LRP to heparan sulfate did not affect the interaction of 37LRP with laminin In contrast, heparan sulfate reduces the extent of binding of laminin to 67LR. Taken together, these results show that 37LRP has some of the biological activities of 67LR, even prior to the conversion event. However, the conversion affects the sites of interaction with both laminin and heparan sulfate.

Physicochemical characterisation and drug release properties of celecoxib hot melt extruded glass solutions

Formulation of Celecoxib into solid dosage forms is difficult due to the physical properties of the drug powder. However for the first time, this paper reports on the drug delivery characteristics glass solutions of celecoxib and polyvinylpyrrolidone prepared by hot melt extrusion, together with use of supercritical carbon dioxide to achieve a porous structure, in order to achieve a stable and enhanced drug release.

The natriuretic peptide/helokinestatin precursor from Mexican beaded lizard (Heloderma horridum) venom: Amino acid sequence deduced from cloned cDNA and identification of two novel encoded helokinestatins

Natriuretic peptides are common components of reptile venoms and molecular cloning of their biosynthetic precursors has revealed that in snakes, they co-encode bradykinin-potentiating peptides and in venomous lizards, some co-encode bradykinin inhibitory peptides such as the helokinestatins. The common natriuretic peptide/helokinestatin precursor of the Gila Monster, Heloderma suspectum, encodes five helokinestatins of differing primary structures. Here we report the molecular cloning of a natriuretic peptide/helokinestatin precursor cDNA from a venom-derived cDNA library of the Mexican beaded lizard (Heloderma horridum). Deduction of the primary structure of the encoded precursor protein from this cloned cDNA template revealed that it consisted of 196 amino acid residues encoding a single natriuretic peptide and five helokinestatins. While the natriuretic peptide was of identical primary structure to its Gila Monster (H. suspectum) homolog, the encoded helokinestatins were not, with this region of the common precursor displaying some significant differences to its H. suspectum homolog. The helokinestatin-encoding region contained a single copy of helokinestatin-1, 2 copies of helokinestatin-3 and single copies of 2 novel peptides, (Phe)(5)-helokinestatin-2 (VPPAFVPLVPR) and helokinestatin-6 (GPPFNPPPFVDYEPR). All predicted peptides were found in reverse phase HPLC fractions of the same venom. Synthetic replicates of both novel helokinestatins were found to antagonize the relaxing effect of bradykinin on rat tail artery smooth muscle. Thus lizard venom continues to provide a source of novel biologically active peptides. (C) 2011 Published by Elsevier Inc.

Synthesis of a tri(organoplatinum) complex via the double directed lithiation of a mono(organoplatinum) precursor

The new diarylplatinum complex Cis-[Pt(PEt(3))(2){C6H3(CH(2)NMe(2))(2)-3,5}(2)] 1, containing four free amine coordination sites, undergoes directed lithiation with Bu(t)Li and subsequent transmetallation with [PtCl2(SEt(2))(2)] to give a triplatinum species 3 which reductively eliminates the diplatinum complex[ClPt{2,6-(Me(2)NCH(2))(2)C6H2-C6H2(CH(2)NMe(2))(2)-2,6}PtCl] 4.

OXOIRON(IV) PORPHYRINS DERIVED FROM CHARGED IRON(III) TETRAARYLPORPHYRINS AND CHEMICAL OXIDANTS IN AQUEOUS AND METHANOLIC SOLUTIONS

The oxidation of six charged iron(III) tetraarylporphyrins with chemical oxidants has been investigated. In aqueous solution each can be converted by tert-butyl hydroperoxide or monopersulphate into its corresponding oxoiron(IV) porphyrin, whereas in methanol only the iron(III) tetra(N-methylpyridyl)porphyrins form detectable ferryl porphyrins at ambient temperatures. On standing, the iron species revert to the parent porphyrin with a small loss due to non-reversible oxidative destruction. That the oxidised porphyrin intermediates are oxoiron(IV) species has been determined using UV-VIS, resonance Raman, H1 NMR and EPR spectroscopy.

Transport properties of protic ionic liquids, pure and in aqueous solutions: Effects of the anion and cation structure

Ionic conductivities of twelve protic ionic liquids (PILs) and their mixtures with water over the whole composition range are reported at 298.15 K and atmospheric pressure. The selected PILs are the pyrrolidinium-based PILs containing nitrate, acetate or formate anions; the formate-based PILs containing diisopropylethylammonium, amilaminium, quinolinium, lutidinium or collidinium cations; and the pyrrolidinium alkylcarboxylates, [Pyrr][CnH2n+1COO] with n = 5–8. This study was performed in order to investigate the influence of molecular structures of the ions on the ionic conductivities in aqueous solutions. The ionic conductivities of the aqueous solutions are 2–30 times higher than the conductivities of pure PILs. The maximum in conductivity varies from ww=0.41???to???0.74 and is related to the nature of cations and anions. The molar conductance and the molar conductance at infinite dilution for (PIL + water) solutions are then determined. Self-diffusion coefficients of the twelve protic ionic liquids in water at infinite dilution and at 298.15 K are calculated by using the Nernst–Haskell, the original and the modified Wilke–Chang equations. These calculations show that similar values are obtained using the modified Wilke–Chang and the Nernst–Haskell equations. Finally, the effective hydrodynamic (or Stokes) radius of the PILs was determined by using the Stokes–Einstein equation. A linear relationship was established in order to predict this radius as a function of the anion alkyl chain length in the case of the pyrrolidinium alkylcarboxylates PILs.

Hydrothermal synthesis of a continuous zeolite Beta layer by optimization of time, temperature and heating rate of the precursor mixture

Highly crystalline zeolite Beta coatings in a range of Si/Al ratios of 12-23 were synthesized on a surface-modified molybdenum substrate by hydrothermal synthesis. The average thickness of the coatings was ca. 2 mu m corresponding to a coverage of 2.5 gm(-2). The coatings were obtained from a viscous Na, K, and TEAOH containing aluminosilicate precursor mixture with silica sol as reactive silicon source. A mechanism for the in situ growth of zeolite Beta coatings is proposed. According to this mechanism, the deposition of an amorphous gel layer on the substrate surface in the initial stage of the synthesis is an important step for the crystallization of continuous zeolite Beta coatings. The heating rate of the precursor mixture and the synthesis temperature were optimized to control the level of supersaturation and to stimulate the initial formation of a gel layer. At a Si/Al ratio of 23, fast heating and a temperature of 150 degrees C are required to obtain high coverage, while at a Si/Al ratio of 15, hydrothermal synthesis has to be performed with a slow initial heating rate at 140 degrees C. (c) 2007 Elsevier Inc. All rights reserved.