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Medical records of a single private practice (Illinois, USA) were retrospectively reviewed to identify dogs (n = 24) that had an open hip reduction with a transarticular suture stabilisation technique after presenting with a traumatic coxofemoral luxation between April 2003 and December 2018. Dogs that met the inclusion criteria were of various breeds with a median body weight of 18.1 (min 4.2, max 54.5) kg and mean age at presentation of 6.5 (min 1, max 11) years. The surgical technique, short-term outcome and complications were extracted from the medical records. Long-term (>2 years) follow-up data was obtained by a telephone interview with each owner. All dogs underwent open hip reduction using a novel transarticular suture stabilisation technique. The outcome was reported by owners to be excellent in 18/24 (75%) dogs with full return of limb function. Sixty-six percent (16/24) of owners reported that no lameness was observed 2 months after surgery. No minor complications were noted in this study. The hips of 6/24 (25%) dogs reluxated after surgery (defined as a major complication), which required femoral head and neck excision surgery. Open coxofemoral joint reduction using a novel transarticular suture technique is a viable surgical option to consider in dogs that present with a traumatic coxofemoral luxation. [ABSTRACT FROM AUTHOR]

A study of the way key companies shop for health care yields valuable lessons for purchasers -- and close-ups of the smallest of those firms show that strategy is at least as important as size. [ABSTRACT FROM AUTHOR]

The momentum profiles from positron annihilation with core electrons in Al have been observed with a recently developed two-detector Doppler-broadening technique. Independent-particle-model (IPM) calculations are in good agreement with the experimental results beyond twice the Fermi momentum and suggest the absence of strong positron-electron correlation effects in this region. Comparisons of calculations with properly normalized momentum profiles indicate that high-momentum core contributions may provide information on the nature of vacancy-type defects and self-trapping effects., Physics

With use of bromine atoms, deposited on the surface of a silicon single crystal, the presence of x-ray standing waves above the crystal surface has been detected under conditions of strong Bragg diffraction., Physics

Interference effects have been observed when coherently related x-ray beams are Compton scattered from an atomic system. We use dynamical diffraction methods to prepare the initial x-ray state and observe the coherent Compton effect in both crosssection and profile measurements., Physics

Introduction: Musculoskeletal problems reported by school children using computers have often been linked to bad posture. This study investigates whether posture education affects the reported prevalence of musculoskeletal symptoms among secondary school children using computers. Methods: A prospective, blinded, randomized, controlled trial was conducted of 71 school children, aged 11 to 12 years, from a school in Leicestershire, UK. Both intervention and control groups received posture training delivered by teachers at the school and both were assessed on their knowledge of correct posture. A follow-up lesson was delivered I week later, during which the intervention group also received automated posture warnings and tips on their personal computers. The prevalence and severity of musculoskeletal symptoms were measured at the start of the study and at end of the follow-up lesson. Results: By the end of the follow-up lesson, the incidence of musculoskeletal problems in the intervention group had fallen from 32% to 5%, while that for the control group had fallen from 29% to 21%. Visual analog pain scale representation of the degree of discomfort due to the musculoskeletal problems had fallen from 1.53 to 0.39 for the intervention group, while that for the control group had only fallen 1.23 to 1.13. Conclusion: Postural interventions that include reminders during the course of the lesson are effective reducing the reported incidence of musculoskeletal problems and severity of pain in school children. This approach should be considered by those devising ergonomic correction programs for school children. [ABSTRACT FROM AUTHOR]

Condensed tannins (proanthocyanidins) are an important factor in the nutritive and dietary quality of many forage crops. We report here experiments aimed at altering the levels and monomer composition of condensed tannins (CTs) in 'hairy root' cultures of Lotus corniculatus (bird's foot trefoil) using genetic manipulation. An Antirrhinum majus dihydroflavonol reductase (DFR) cDNA was expressed in sense in L. corniculatus and CT levels in transgenic root cultures were analysed. Two co-transformed lines were noted with decreased CT content relative to controls and these levels were comparable with antisense-DFR phenotypes. In ADFR10, a co-transformed line with the highest CT levels, CT structure was altered in a manner consistent with the substrate specificity of the introduced gene; that is an increase in pro-pelargonidin monomers noted after hydrolysis of CTs. RT-PCR confirmed the expression of endogenous DFR gene(s) in both putatively co-suppressed lines and also in ADFR10. Analysis of selected root culture lines indicated that the monomer composition of CTs did not change during growth and development but that levels of CTs varied in a regulated manner.

Two transgenic tobacco lines were genetically engineered to contain chimaeric genes encoding the glutamine synthetase (GS) gamma polypeptide of Phaseolus vulgaris (French bean), expressed from the cauliflower mosaic virus 35S promoter. One (MIT-1) contained two copies of a construct including the first 60 amino acids of the Nicotiana plumbaginifolia beta-F1 ATPase to target the GS polypeptide to the mitochondrion. The other (CYT-4) contained a single copy of a cytosolic GS construct. Leaves of in vitro plantlets expressed the constructs and contained a novel GS polypeptide, which assembled into active GS isoenzymes constituting about 25% of the total GS activity. In in vitro plantlets of MIT-1, but not CYT-4, the novel polypeptide was found to be associated with the mitochondria. Moreover in MIT-1, the size of the novel polypeptide was not that predicted of the precursor (44.9 kDa) but was about 39 kDa, the same size as the authentic GS gamma polypeptide in CYT-4. These results are consistent with the precursor being imported into the mitochondria and cleaved near the fusion junction between the two sequences. These experiments have therefore shown that the presequence of the beta-F1 ATPase has successfully targeted the GS gamma polypeptide to the mitochondria of transgenic tobacco where it has assembled into an active isoenzyme. However, in fully regenerated plants growing photoautotrophically in growth-room conditions, although the constructs were still expressed, the gamma polypeptide did not accumulate to the same levels as in in vitro plantlets and new isoenzyme activities were now barely detectable. Moreover in leaves of the mature MIT-1 plants, the gamma polypeptide was found to be associated with the insoluble fraction of the mitochondria. The results of these experiments are discussed.

The enzyme prolyl hydroxylase (proline: 2-oxoglutarate dioxygenase, EC 1.14.11.12), induced in suspension-cultured cells of Phaseolus vulgaris L. (French bean) by treatment with an elicitor preparation from the phytopathogenic fungus Colletotrichum lindemuthianum, has been investigated. The enzyme, which catalyses the hydroxylation of poly-L-proline with the stoichiometric decarboxylation of 2-oxoglutarate, has been shown to be localized mainly in smooth endoplasmic reticulum. After solubilization from microsomal membranes, the hydroxylase was purified by ion-exchange chromatography and affinity chromatography on poly-L-proline-Sepharose 4B. The subunit Mr, as assessed by sodium dodecyl sulphate/poly-acrylamide-gel electrophoresis, was 65 000, the subunit apparently being recovered as a doublet: the subunits associate under non-denaturing conditions to give at least a tetramer. The bean hydroxylase has kinetic properties and cofactor requirements similar to those previously reported for the enzyme from other plants. Elicitor treatment of suspension-cultured bean cells leads to a rapid induction of prolyl hydroxylase activity concomitant with induction of a protein: arabinosyl-transferase and increased levels of an arabinosylated hydroxyproline-rich protein.

Treatment of cell suspension cultures of bean (Phaseolus vulgaris c.v. Immuna) with an elicitor preparation heat-released from the cell walls of the phytopathogenic fungus Colletotrichum lindemuthianum resulted in rapid changes in the composition of the bean cell walls. These consisted of (a) increases in phenolic material bound to the cellulosic and hemicellulosic fractions of the wall, (b) loss of material (mainly glucose) from the hemicellulosic fraction and (c) an increase in wall-associated hydroxyproline. The increases in wall-bound phenolics were preceded by (a) rapid decreases in the intracellular levels of free hydroxycinnamic acids and (b) transient increases in the extractable activities of L-phenylalanine ammonia-lyase and cinnamic acid 4-hydroxylase. 4-Hydroxycinnamic acid 3-hydroxylase activity was present at a high level in control cultures and was not induced by elicitor. Changes in the levels of cytochrome P-450, as determined by dot blot assays utilising an anti-(P-450) monoclonal antibody, paralleled the changes in cinnamic acid 4-hydroxylase activity. The accumulation of cell wall hydroxyproline was associated with rapid transient increases in the extractable activities of proline 2-oxoglutarate dioxygenase and a protein arabinosyl transferase. An hydroxyproline-rich acceptor protein of Mr 42 500 was the major protein to incorporate [3H]arabinose following elicitation of the bean cells, and the kinetics of the extent of labelling of this protein paralleled the accumulation of hydroxyproline protein in the endomembrane system. The above metabolic changes associated with cell wall components followed rapid kinetics similar to those involved in the formation of the phytoalexin kievitone in the elicited cultures [Robbins, M. P. et al. (1985) Eur. J. Biochem. 148, 563-569]. It is therefore concluded that increased 5-hydroxy-substituted isoflavonoid biosynthesis, wall-bound phenolic synthesis and synthesis of arabinosylated hydroxyproline-rich protein are all early events which are closely linked to the initial interaction between plant cell and fungal elicitor.

Changes in the rates of synthesis of three enzymes of phenyl-propanoid biosynthesis in Phaseolus vulgaris L. (dwarf French bean) have been investigated by immunoprecipitation of [S]methionine-labeled enzyme subunits with mono-specific antisera. Elicitor causes marked, rapid but transient co-ordinated increases in the rate of synthesis of phenyl-alanine ammonia-lyase, chalcone synthase and chalcone isomerase concomitant with the phase of rapid increase in enzyme activity at the onset of accumulation of phenyl-propanoid-derived phytoalexin antibiotics in suspension cultures of P. vulgaris. Co-ordinate induction of enzyme synthesis is also observed in hypocotyl tissue during race:cultivar-specific interactions with Colletotrichum lindemuthianum, causal agent of anthracnose. In an incompatible interaction (host resistant) there are early increases apparently localized to the initial site of infection prior to the onset of phytoalexin accumulation and expression of hypersensitive resistance. In contrast, in a compatible interaction (host susceptible) there is no induction of synthesis in the early stages of infection, but a delayed widespread response at the onset of lesion formation associated with attempted lesion limitation. It is concluded that expression of the phytoalexin defense response in biologically stressed cells of P. vulgaris characteristically involves co-ordinate induction of synthesis of phytoalexin biosynthetic enzymes.

Chalcone isomerase, an enzyme involved in the formation of flavonoid-derived compounds in plants, has been purified nearly 600-fold from cell suspension cultures of dwarf French bean (Phaseolus vulgaris L.). Chromatofocussing yielded a single form of the enzyme of apparent pI 5.0. This preparation was used to raise rabbit anti-(chalcone isomerase) serum. Changes in the rate of synthesis of chalcone isomerase have been investigated by indirect immunoprecipitation of enzyme labelled in vivo with [35S]methionine in elicitor-treated cultures of P. vulgaris. Elicitor, heat-released from cell walls of the phytopathogenic fungus Colletotrichum lindemuthianum, the causal agent of anthracnose disease of bean, causes increased synthesis of the isomerase, with maximum synthetic rate occurring 11-12 h after exposure to elicitor. Immune blotting studies indicate that the elicitor-mediated increase in extractable activity of the isomerase is associated with increased appearance of immunodetactable isomerase protein of Mr 27 000. However, the maximum level of immunodetectable isomerase was attained approximately 6 h earlier than maximum extractable activity. Furthermore, a 2.8-fold increase in enzyme activity above basal levels at 12 h after elicitor-treatment was associated with a corresponding 5.8-fold increase in immunodetectable enzyme. It is concluded that elicitor induces the synthesis of both active and inactive chalcone isomerase of Mr 27 000, and that some activation of inactive enzyme occurs during the elicitor-mediated increase in isomerase activity. The presence of a pool of inactive chalcone isomerase in bean cell cultures has recently been suggested on the basis of density labelling experiments utilising 2H from 2H2O [Dixon et al. (1983) Planta (Berl.) 159, 561-569].

Approximately fourfold increases in the extractable activity of the enzyme chalcone isomerase (CHI, EC 5.5.1.6) were observed within 24 h of treatment of cell suspension cultures of Phaseolus vulgaris with a crude elicitor preparation heatreleased from the cell walls of the bean pathogen Colletotrichum lindemuthianum. The induction of CHI activity was highly dependent upon elicitor concentration, with maximum induction occurring in two discrete concentration ranges. A basal half-life for CHI>32 h in control cultures was determined by labelling with (2)H from (2)H2O followed by analysis of the equilibrium distribution of enzyme activity in CsCl density gradients. Comparative density labelling indicated that at both the lower and higher effective elicitor concentrations, the induced appearance of CHI activity was the result of an apparent initial activation of pre-existing enzyme followed by an increase in the rate of de-novo synthesis of the enzyme as compared with non-elicited controls. The increased appearance of the enzyme over the first 8 h in elicitor-treated cultures was inhibited by cycloheximide, cordycepin and actinomycin D. The results are discussed in relation to the mechanisms of co-ordinate enzyme induction operating in French-bean cell cultures exposed to fungal elicitors.

DNAs complementary to poly(A)(+) RNA present in elicitor-treated cells of Phaseolus vulgaris L. were inserted into pBR325 and used to transform Escherichia coli strain JA221. A clone was identified that contained sequences complementary to mRNA encoding chalcone synthase, a regulatory enzyme of phenylpropanoid biosynthesis, which catalyzes the first reaction of a branch pathway specific to flavonoid and isoflavonoid biosynthesis. Rapid, marked but transient increases in chalcone synthase mRNA in response to elicitor treatment were observed by RNA blot hybridization with (32)P-labeled chalcone synthase cDNA sequences. Induction of chalcone synthase mRNA governs the rate of enzyme synthesis throughout the phase of rapid increase in enzyme activity at the onset of accumulation of isoflavonoid-derived phytoalexins. The data are consistent with the hypothesis that elicitor causes a rapid transient stimulation of transcription of chalcone synthase gene(s) as an early event in the expression of the phytoalexin defense response.

Treatment of cell suspension cultures of Phaseolus vulgaris c.v. Immuna with an elicitor preparation heat-released from the cell walls of the phytopathogenic fungus Colletotrichum lindemuthianum resulted in rapid accumulation of the prenylated 5-hydroxyisoflavanone phytoalexin kievitone followed by later accumulation of the pterocarpan-derived phytoalexin phaseollin. Kievitone formation was preceded by rapid transient increases in the extractable activities of the enzymes L-phenylalanine ammonia-lyase and chalcone synthase. The extractable activities of 15 enzymes were measured in the cell cultures during the period of kievitone accumulation. The results suggest a highly selective induction of enzymes associated directly with the phytoalexin pathway. No induction of enzymes of pathways diverging from or providing substrates for the phenylpropanoid----isoflavonoid pathway was observed. The increase in glutamate dehydrogenase activity in control cultures was prevented by elicitor application. A comparison of enzyme activities in control and Colletotrichum-infected bean hypocotyls provided further evidence of the selective induction of enzymes of phytoalexin synthesis, although peroxidase, glutamate dehydrogenase and glutamate synthase activities were higher in infected than in healthy hypocotyls. It is concluded that the major enzymic changes occurring in elicitor-treated bean cells are probably those directly associated with defence mechanisms such as the formation of isoflavonoid phytoalexins (this paper) or accumulation of phenolic compounds and hydroxyproline-protein in the cell walls [Bolwell, G. P. et al. (1985) Eur. J. Biochem. 148, 571-578].