Water depth modifies back kinematics of horses during water treadmill exercise.

REASONS FOR PERFORMING STUDY: Water treadmill exercise can be incorporated into the rehabilitation programmes of horses recovering from back pathology, yet little is known about the effect of this type of exercise on thoracolumbar movement ranges. OBJECTIVES: To measure the flexion-extension range of motion (FE ROM) of the thoracolumbar spine and pelvic vertical displacement during water treadmill walking at 3 water depths and compare these with the control condition. STUDY DESIGN: Within-subject trial using a crossover design in healthy horses. METHODS: A total of 14 horses walked at 0.8 m/s on a water treadmill for 3 min at each of the following depths; hoof (control), metatarsophalangeal joint (low), tarsal joint (medium) and femoropatellar joint (high). Skin surface markers on T6, T10, T13, T18, L3, L5 and S3 were used to obtain FE ROM and the minimum and maximum angular motion pattern values (AMPmin and AMPmax) for T10, T13, T18, L3 and L5. Markers placed on left and right tuber coxae were used to obtain pelvic vertical displacement. Friedman's tests and post hoc Wilcoxon's signed ranks tests were used to determine the effects of water depth on measured variables. RESULTS: The FE ROM of T10 (8.4°), T13 (8.1°), T18 (6.9°) and L3 (6.4°) when walking at high depth was significantly greater than control (5.5, 5.7, 5.1 and 5.1°, respectively; P<0.008); T13 AMPmin was significantly lower in high water (-3.0°) than control (0.1°, P = 0.001) and L3 AMPmax significantly greater in high water (-1.9°) than control (-4.8°, P = 0.001). There was no significant association between pelvic vertical displacement and water depth. CONCLUSIONS: Walking in high water causes cranial thoracic extension and thoracolumbar flexion when compared with walking in water at hoof depth. This postural change should be considered when designing rehabilitation programmes for horses with back and/or hindlimb pathology.

Clustering of Environments of Southern Soft Red Winter Wheat Region for Milling and Baking Quality Attributes.

Division of regional nursery test sites into homogenous subregions contributes to more efficient evaluation and better differentiation of cultivars. Data from the Uniform Southern Soft Red Winter Wheat Nursery (USSRWWN) were analyzed to group testing sites into relatively homogenous subregions for milling and baking quality (MBQ) attributes. Environmental effects due to years accounted for over 50% of the total variation for protein content (P) and 42% for alkaline water retention capacity (AWRC). Genotype effect accounted for 63% of the total variation for softness equivalence (SE), and 37% for flour yield (FLY). A significant genotype x location (GxL) interaction occurred for FLY and P. However, the GxL variance component accounted for a small proportion of the total phenotypic variance, suggesting that clustering would be more beneficial for resource efficiency than for increasing differentiation of genotypes. A hierarchical cluster analysis was used to group locations on the basis of GxL interaction effects for FLY, P, AWRC, and SE. Cluster analysis divided the USSRWWN into two main subregions within which the GxL interaction was reduced by over 90% for FLY and by 60% for P. Although this classification is not entirely consistent with the geographic distribution of locations, clusters do follow general geographic-climatic-disease regions. Our results suggest that the USSR-WWN can be divided into subregions to reduce the resources expended on evaluation of MBQ attributes. This classification of locations could be useful in breeding for specific adaptability within subregions.

Chronic systemic administration of salmeterol to rats promotes pulmonary beta(2)-adrenoceptor desensitization and down-regulation of G(s alpha).

1. The aim of the present study was to examine the effects of chronic infusion of the long-acting agonist salmeterol on pulmonary beta(2)-adrenoceptor function in Sprague-Dawley rats in vivo and to elucidate the molecular basis of any altered state. 2. Systemic administration of rats with salmeterol for 7 days compromised the ability of salmeterol and prostaglandin E(2) (PGE(2)), given acutely by the intravenous route, to protect against ACh-induced bronchoconstriction when compared to rats treated identically with vehicle. 3. beta(1)- and beta(2)-adrenoceptor density was significantly reduced in lung membranes harvested from salmeterol-treated animals, which was associated with impaired salmeterol- and PGE(2)-induced cyclic AMP accumulation ex vivo. 4. Three variants of G(s alpha) that migrated as 42, 44 and 52 kDa peptides on SDS polyacrylamide gels were detected in lung membranes prepared from both groups of rats but the intensity of each isoform was markedly reduced in rats that received salmeterol. 5. The activity of cytosolic, but not membrane-associated, G-protein receptor-coupled kinase was elevated in the lung of salmeterol-treated rats when compared to vehicle-treated animals. 6. The ability of salmeterol, administered systemically, to protect the airways of untreated rats against ACh-induced bronchoconstriction was short-acting (t(off) approximately 45 min), which contrasts with its long-acting nature when given to asthmatic subjects by inhalation. 7. These results indicate that chronic treatment of rats with salmeterol results in heterologous desensitization of pulmonary G(s)-coupled receptors. In light of previous data obtained in rats treated chronically with salbutamol, we propose that a primary mechanism responsible for this effect is a reduction in membrane-associated G(s alpha). The short-acting nature of salmeterol, when administered systemically, and the reduction in beta-adrenoceptor number may be due to metabolism to a biologically-active, short-acting and non-selective beta-adrenoceptor agonist.

Albuterol-induced downregulation of Gsalpha accounts for pulmonary beta(2)-adrenoceptor desensitization in vivo.

The aim of the present study was to develop a chronic in vivo model of pulmonary beta(2)-adrenoceptor desensitization and to elucidate the nature and molecular basis of this state. Subcutaneous infusion of rats with albuterol for 7 days compromised the ability of albuterol, given acutely, to protect against acetylcholine-induced bronchoconstriction. The bronchoprotective effect of prostaglandin E(2), but not forskolin, was also impaired, indicating that the desensitization was heterologous and that the primary defect in signaling was upstream of adenylyl cyclase. beta(2)-Adrenoceptor density was reduced in lung membranes harvested from albuterol-treated animals, and this was associated with impaired albuterol-induced cyclic adenosine monophosphate (cAMP) accumulation and activation of cAMP-dependent protein kinase ex vivo. Gsalpha expression was reduced in the lung and tracheae of albuterol-treated rats, and cholera toxin-induced cAMP accumulation was blunted. Chronic treatment of rats with albuterol also increased cAMP phosphodiesterase activity and G protein-coupled receptor kinase-2, but the extent to which these events contributed to beta(2)-adrenoceptor desensitization was unclear given that forskolin was active in both groups of animals and that desensitization was heterologous. Collectively, these results indicate that albuterol effects heterologous desensitization of pulmonary Gs-coupled receptors in this model, with downregulation of Gsalpha representing a primary molecular etiology.

Induction of phosphodiesterases 3B, 4A4, 4D1, 4D2, and 4D3 in Jurkat T-cells and in human peripheral blood T-lymphocytes by 8-bromo-cAMP and Gs-coupled receptor agonists. Potential role in beta2-adrenoreceptor desensitization.

In this study, a potential mechanism of beta2-adrenoreceptor desensitization has been explored that is based upon the enhanced degradation of cAMP by phosphodiesterase (PDE). Pretreatment of Jurkat T-cells with 8-bromo cAMP (8-Br-cAMP) or prostaglandin E2 increased PDE3 and PDE4 activity in an actinomycin D- and cycloheximide-sensitive manner. This effect was associated with increased expression of HSPDE3B, HSPDE4A4, HSPDE4D1, HSPDE4D2, and HSPDE4D3 mRNA transcripts. Western analysis reproducibly labeled a band of immunoreactivity in vehicle-treated cells that corresponded to HSPDE4A4 (125 kDa). Although the intensity of this band was unchanged in cells treated with 8-Br-cAMP, additional 68-72-kDa proteins (HSPDE4D2, HSPDE4D1) were labeled that were not detected after vehicle. Similar results were obtained with T-lymphocytes exposed to 8-Br-cAMP and fenoterol. However, in those experiments HSPDE4A4 and HSPDE4D1 appeared to be equally expressed in vehicle- and treated cells, whereas HSPDE4D2 (72 kDa) was detected only after 8-Br-cAMP. The up-regulation of PDE activity in Jurkat T-cells abolished the ability of isoproterenol to elevate cAMP, which was partially reversed by the non-selective PDE inhibitor, 3-isobutyl-1-methylxanthine, and by the PDE3 and PDE4 inhibitors, Org 9935 and rolipram, respectively. Collectively, these data suggest that chronic treatment of T-cells with cAMP-elevating agents compromises beta2-adrenoreceptor-mediated cAMP accumulation by increasing the expression of HSPDE3B and HSPDE4D gene products.

Studies with a bivalent infectious bronchitis killed virus vaccine.

Haemagglutination inhibition and virus neutralisation antibody responses of chickens given different vaccination programmes were compared. This was followed by a further experiment in which variously vaccinated laying hens were challenged at 30 weeks of age with two strains of infectious bronchitis virus of the "variant" Dutch D207 serotype. Chickens were given primary vaccinations to different strains of infectious bronchitis live virus during rearing and then injected at 16 weeks of age with inactivated oil adjuvanted virus vaccines prepared from either M41, GV101 or both viruses combined (bivalent vaccine). Antibody titres to M41 infectious bronchitis virus were high, and to D207 serotype low. in birds given Mass type vaccines only. In birds given an initial 'priming' with Mass type live vaccine and then 'boosted' with bivalent killed vaccine, high haemagglutination inhibition and virus neutralisation antibody levels against both the M41 and D207 serotypes of infectious bronchitis virus were stimulated. In another experiment, the ability of laying hens vaccinated according to this programme, to withstand challenge with two strains of virulent infectious bronchitis virus of the D207 serotype, was tested. Protection of egg production in vaccinated hens was found to be good and in all groups correlated with the individual hen haemagglutination inhibition titre at the time of challenge. The significance of these results with regard to the use of killed virus vaccines in laying hens and to the necessity to develop live virus vaccines from 'variant' strains of infectious bronchitis virus is discussed.

A live attenuated turkey rhinotracheitis virus vaccine. 1. Stability of the attenuated strain.

Compared with the severe clinical disease caused by two virulent strains of turkey rhinotracheitis virus (TRTV), an attenuated strain has been shown to cause only slight respiratory infection in 7-day-old TRT-free turkey poults, yet still to be capable of stimulating TRT antibodies and of protecting the poults against challenge with virulent TRTV 21 days later. The stability of the attenuation during 12 turkey-turkey passages of the strain has been demonstrated; the poult passaged and prepassaged strains causing only mild respiratory signs even when bacteria, known to be associated with severe outbreaks of TRT in the field, were included in the inoculum.

A live attenuated turkey rhinotracheitis virus vaccine. 2. The use of the attenuated strain as an experimental vaccine.

An attenuated turkey rhinotracheitis (TRT) vaccine strain, when given either by eye drop or by aerosol, has been shown to be effective in protecting 1- to 11-day-old turkey poults against an experimental challenge with TRTV up to 14 weeks later. TRT antibody-free poults and poults hatched from TRT-immune dams were both equally well protected, although a high proportion of the latter did not respond serologically to the vaccine. As little as 1 CD50 of vaccine was found to be effective in protecting poults against challenge. Immunity developed within about 6 days of vaccination of 7-day-old TRT antibody-free poults and humoral antibody persisted for at least 14 weeks after a single vaccination at 4 weeks of age.

Infectious bronchitis in laying hens: the relationship between haemagglutination inhibition antibody levels and resistance to experimental challenge.

In three separate and unrelated experiments, in which vaccinated hens were challenged with virulent infectious bronchitis virus, the ability of individual hens to maintain egg production was related to their serum haemagglutination inhibition antibody titre at the time of challenge. It was found that, regardless of the vaccination programme used, the ability of laying hens to withstand infectious bronchitis virus challenge, as measured by the effect upon their egg production, is directly related to individual antibody titre at the time of challenge. In all three experiments, birds with antibody titres of >/=8 Iog2 (n = 82) did not show a significant reduction in egg production after challenge while those with titres within the range 5-7 log(2) inclusive (n = 126), over a period of 3 or 4 weeks after challenge, showed a significant reduction in their rate of egg lay, viz: 0.38, 0.33 and 0.47 eggs per hen per week, respectively and those with titres <4 log(2) (n = 101) showed, over the same time period, a reduction of 1.0, 0.45 and 1.16 eggs per hen per week, respectively. The ability of different vaccination programmes to stimulate uniformly high antibody responses to infectious bronchitis virus, and hence good overall protection of egg production was compared. It is concluded that the programme of choice is first to vaccinate the birds with a highly attenuated strain of live infectious bronchitis vaccine during rearing (H120), followed by the injection of a potent killed oil emulsion adjuvant vaccine at point-of-lay. The ability of the less attenuated H52 strain of live infectious bronchitis vaccine to interfere with response to killed vaccine was demonstrated in two of the three experiments. In both cases this interference was accompanied by an increased susceptibility of the hens to the effect of infectious bronchitis virus challenge on egg production.

Impaired response to killed Newcastle disease vaccine in chicken possessing circulating antibody to chicken anaemia agent.

Broiler breeder hens from the same hatch were reared as two separate flocks, one in the field and one in experimental accommodation. Both received the same vaccination programme using the same batches of vaccines. One flock showed serological evidence of infection with chicken anaemia agent starting at 8 weeks, the other starting at 22 weeks old. Newcastle disease mean antibody titres 4 weeks after killed vaccine injected at 18 or 19 weeks old were 4.6 logs lower in the flock showing chicken anaemia agent antibody from 8 weeks old than in the flock seroconverting at 22 weeks. Three other field flocks showing poor responses to killed Newcastle disease vaccines were examined and found to be chicken anaemia agent positive when vaccinated: a further three flocks showing good Newcastle disease antibody responses were shown to be chicken anaemia agent-antibody negative. No difference in response to infectious bronchitis or infectious bursal disease killed vaccines was demonstrable between the two trial flocks. The significance of chicken anaemia agent as a potential immunosuppressive agent for chickens is discussed with special reference to the control of Newcastle disease in laying and breeding hens.

An enzyme-linked immunosorbent assay (ELISA) for anti-chlamydial secretory immunoglobulin A in guinea pig tears.

A method is described which permits the assay of specific secretory immunoglobulin A (sIgA) antibodies produced by guinea pigs in response to ocular infection with the guinea pig inclusion conjunctivitis strain of Chlamydia psittaci (GPIC agent). The enzyme-linked immunosorbent assay (ELISA) developed was shown to be more sensitive and less subjective than the micro-immunofluorescence assay as a means of assaying specific antibody.

Continuous noninvasive monitoring of pH and temperature in rat Walker 256 carcinoma during normoglycemia and hyperglycemia.

The extracellular pH and temperature of Walker 256 carcinoma and of normal subcutaneous tissue were measured continuously in unanesthetized female Sprague-Dawley rats for up to 20 hours following glucose or galactose administration. The pH was monitored with flexible glass electrodes contained in micropore chambers implanted in the flank of a rat. Temperature was measured with miniature thermistor probes incorporated in the tumor or in subcutaneous tissue. The pH in the untreated Walker 256 carcinoma decreased linearly from approximately 7.3 to 6.2 with increasing tumor mass up to 50 g. Administration of glucose (6 g/kg body wt, ip) in tumor-bearing rats increased glucose concentrations in blood and tumor, as well as lactic acid concentration in tumor, and had no significant effect on lactic acid concentration in blood. Plasma volume was not affected by either glucose or galactose loading as compared to that in rats given saline alone. However, the blood viscosity increased by up to 30% within 30 minutes after galactose injection, but not after glucose injection, and this significant difference in viscosities persisted for approximately 6 hours after glucose and galactose injections. In small tumors (less than 10 g), a decrease of up to 1 pH unit was observed within 6 hours after glucose administration, and the return of pH to pretreatment values began about 10 hours after glucose injection. Response of large ulcerated tumors (greater than 20 g) was not as uniform; the pH decreased by about 0.5 to 1 pH unit for only a brief period. After galactose injection, pH in some tumors remained unchanged, whereas in others an average decrease of about 0.2 pH units was observed. The pH in normal tissue was not affected by glucose or galactose administration. Both glucose and galactose decreased tumor temperature by about 7 degrees C.

Enhanced metastasis formation by combined hyperthermia and hyperglycemia in rats bearing Walker 256 carcinosarcoma.

Hyperglycemia has been shown to decrease tumor pH and blood flow rates, consequently this could increase the sensitivity of tumor to hyperthermia. Combined waterbath hyperthermia (43 degrees C/2 h) and hyperglycemia (6 g/kg, i.p.) was investigated on survival of rats bearing a metastasizing form of Walker 256 carcinosarcoma. Hyperthermia alone increased the survival rate of animals from 19% to 42%. Hyperglycemia promoted more uniform tumor heating in the foot. However, combined hyperthermia and hyperglycemia led to a significant decrease in the survival rate of animals (10%; P less than 0.001), and most rats died with widespread metastasis in lymph nodes, lungs and kidneys. These findings do not support the postulate that hyperglycemia leads to sensitization of tumor destruction by hyperthermia.

A clinical and biochemical evaluation of Clozic, a novel disease modifying drug in rheumatoid arthritis.

We have compared two dose levels of Clozic, a novel agent with potential anti-rheumatoid activity, to D-penicillamine and aspirin in an observer blind randomised parallel group study of 56 patients with active rheumatoid arthritis. Eight clinical assessments and 26 laboratory assessments were performed on each patient at each visit over a six month period. Results were analysed by conventional methods and also by correlation matrices constructed between clinical and laboratory variables. Patients treated with D-penicillamine (500 mg/day) responded adequately and the control group on aspirin (up to 3.6 g of enteric coated formulation/day) performed well, though the withdrawal rate from this latter group was high, predominantly because of continued disease activity. Patients receiving Clozic (100 mg/day or 300 mg/day) improved more than patients receiving penicillamine, particularly at the higher dose. Comparison of methods of analysis validates the use of correlation matrices both for detecting anti-rheumatoid activity and for determining the optimum dose of a novel compound. This trial illustrates the problems of a study of this nature, with the powerful effect on patients of being enrolled in such a closely monitored investigation. It emphasises the greater value of biochemical changes in following disease changes.

Effects of hyperthermia and hyperglycemia on the metastases formation and on survival of rat bearing W256 carcinosarcoma.

Hyperthermia (temperatures less than 42 degrees C) is widely used in the treatment of cancer. Current thrust in this field is directed towards using agents which can potentiate the effects of hyperthermia. Combined local hyperthermia (43 degrees C/2 hours) and hyperglycemia (6g glucose/kg body weight; mean blood glucose levels of 500 mg%) was investigated for treating a metastasizing form of a rat W256 carcinosarcoma. Glucose loading of the tumor-bearing rats rendered the foot tumors physically more easy to heat (due to inhibition of tumor blood flow), but combined hyperthermia and hyperglycemia lead to a decrease in survival rate (13% compared to 41% with heat alone), most animals died with widespread metastases in lymph nodes, lungs and kidneys. The data does not support the postulate that hyperglycemia leads to sensitization of tumor destruction by hyperthermia. We suggest that Corynebacterium parvum, a non-specific immunostimulant, should be thoroughly investigated as a potentiator of hyperthermia.

Potential for the use of germinated wheat and soybeans to enhance human nutrition.

Wheat and soybeans are the major agricultural exports of the United States. The U.S. sells more of each crop than any other nation. Soybeans are the main staple in China, but the U.S. sells more soybeans than China grows. For hundreds of millions of other people, wheat is the main staple. And yet, most Americans eat whole grains of neither wheat nor soybeans. In the United States, many nutrients of wheat and soybeans are lost in processing or are fed to animals. A highly significant share of the wheat nutrients are lost from the main foodstream when the germ and bran (with aleurone) portions are separated. Whole soybeans are carefully processed for food by only a handful of Americans.