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Biomedical subjects

S D Carter

Publications and source records attributed to S D Carter.

At least 91 records · Page 5Linked to original sources
PubMed1996

Taenia multiceps (Cestoda): Ia antigen expression and prostaglandin secretion by parasite-modified, murine peritoneal macrophages.

Taenia multiceps secretions modify accessory cell activity in macrophages. The present experiments were designed to elucidate the cellular mechanisms involved. While normal, murine peritoneal macrophages amplified mitogen-activated T-cell proliferation, macrophages modified by exposure to parasite secretions inhibited this proliferation. The modified behaviour was shown by glutaraldehyde-fixed as well as living macrophages, and modification was inducible by FPLC fraction 24 of coenurus fluid and was associated with an expanded population of 1a- macrophages. Secretory products of parasite-activated macrophages also inhibited T-cell proliferation, and secretion was prevented by indomethacin. The measurement of modified accessory activity was not influenced by the concentration of tritiated thymidine in lymphocyte proliferation assays. Consequently there is no evidence that the reported events are affected by macrophage-derived, cold thymidine secretion. It is concluded that T. multiceps si able to manipulate macrophage accessory function by mechanisms which involve altered histocompatibility antigen expression and the secretion of prostaglandin.

Animals↗
PubMed1996

The determination of serum concentrations of osteocalcin in growing pigs and its relationship to end-measures of bone mineralization.

Osteocalcin, a 49-amino acid, gamma-carboxyglutamic acid-containing protein produced by the osteoblast, has been shown in laboratory animals to be a better marker of bone turnover than alkaline phosphatase. To determine serum osteocalcin levels in growing pigs, we isolated pure porcine osteocalcin and developed a double-antibody RIA. To evaluate the effects of dietary Ca and P levels on serum osteocalcin, 36 individually penned crossbred pigs (19.5 kg initial BW) were fed fortified corn-soybean meal diets (.95% lysine) containing four levels of Ca (.42, .66, .90, 1.14%) and P (.35, .55, .75, .95%) in a 30-d test. Increasing dietary Ca and P improved body weight gain quadratically (P < .02). Most bone traits improved quadratically (P < .05) with increasing Ca and P. Pigs were bled on d 0, 10, 20, and 30 to determine serum levels of alkaline phosphatase, 1,25-dihydroxyvitamin D3, and osteocalcin. Osteocalcin decreased (P < .02) linearly with increasing Ca and P on d 10, 20, and 30. However, this effect was much more pronounced on d 20 and 30. Alkaline phosphatase decreased with the first incremental increase in dietary Ca and P, but was not affected by higher levels on any day measured. Osteocalcin was inversely correlated with growth rate (r = -.54, P < .01), bone strength (r = -.57, P < .01), metacarpal ash (r = -.29, P < .10), femur ash (r = -.60, P < .01), and femur ash weight (r = -.65, P < .01). Similar results were found for 1,25-dihydroxyvitamin D3. Alkaline phosphatase was not correlated with performance or most bone traits on d 30. Based on this model, these results suggest that serum osteocalcin and 1,25-dihydroxyvitamin D3 are better predictors of bone mineralization and(or) turnover in pigs than serum alkaline phosphatase.

Alkaline Phosphatase↗
PubMed1995

Anti-collagen antibodies and immune complexes in equine joint diseases.

An investigation was made into the possible contribution of autoimmune mechanisms to equine arthropathies. Serum and synovial fluid (SF) immune complexes and anti-collagen Type II antibodies were measured, by ELISA, in groups of horses with naturally occurring osteoarthritis (OA), osteochondritis dissecans (OCD), bone fracture, traumatised joints, synovitis, infected joints and non-diseased (control) joints. Significantly raised anti-collagen Type II antibodies were found in osteoarthritic (P < 0.02) and traumatised joint synovial fluids (P < 0.01) compared with the control, where ten of 38 (26%) OA and five of eight (63%) traumatised joint synovial fluid samples had raised anti-collagen Type II antibodies (above mean and 2 SD of control group; P < 0.05). Significantly raised levels of C1q-binding immune complexes were found in the synovial fluids of horses with OA (P < 0.001), OCD (P < 0.02), fractured articular bone (P < 0.001), infected (P < 0.01) and traumatised joints (P < 0.001) as compared with the control horses. Raised C1q-binding activity (above mean and 2 SD of control group; P < 0.05) was shown in synovial fluids in 18 of 38 (47%) OA, four of 16 (25%) OCD, four of nine (44%) fractured bone, one of eight (14%) synovitis, two of four (50%) infected joints and seven of eight (88%) traumatised joints. No raised anti-collagen Type II antibodies or C1q-binding activity were detected in sera from any clinical group. Correlations were found, in synovial fluids, between anti-collagen Type II antibodies and C1q-binding activity in OA (P < 0.02), synovitis (P < 0.01) and infected joint (P < 0.05) groups. Within individual horses, there were no correlations between the SF and sera measurements of either anti-collagen II or C1q-binding activity. The relationship between cause and effect of these immunological findings cannot be determined; as they are common to many types of equine joint disorder it is probable that they are not an initiating factor in pathology.

Animals↗
PubMed1995

Monoclonal antibodies against camel (Camelus dromedarius) IgG, IgM and light chains.

Monoclonal antibodies specific for camel IgG and IgM heavy chains and immunoglobulin light chains were produced by a simple, time-saving and efficient method. Popliteal lymph nodes isolated 9 days after a primary foot-pad immunisation were used as the source of antibody producing hybridoma cells. Ascites was induced in mice and ascitic fluid collected. The specificity of anti-IgG and anti-IgM monoclonal antibodies was determined by enzyme-linked immunosorbent assay (ELISA) and Western blotting. Monoclonal antibodies specifically reacting to IgG1 subclasses were demonstrated; no monoclonal antibodies specific to IgG2 or IgG3 were generated. An unexpected finding was that some class-specific monoclonal antibodies were light chain, and not heavy chain, reactive.

Animals↗
PubMed1995

Immune responses of the camel (Camelus dromedarius) to contagious ecthyma (Orf) virus infection.

An enzyme-linked immunosorbent assay (ELISA) was developed together with a western blotting technique for the detection of total and specific IgG and IgM antibodies to the contagious ecthyma (orf) virus in camel (Camelus dromedarius) sera and for identifying the seroreactive antigens of the virus. An outbreak of generalised contagious ecthyma in camels was diagnosed for the first time in Libya; the seropositivity rate in a herd with clinically affected camels was 37.9% (and was related to clinical signs) and in apparently normal herds was 0% to 6.8%. Two viral antigenic determinants (22 and 40 kDa) were shared by the western blotting patterns of all the positive camel sera tested, another viral antigenic component of 28 kDa was shared by the positive sera with high ELISA titres. Very close similarity was seen with the western blot of orf-positive sheep sera. It is considered that the ELISA technique was valid for orf serodiagnosis in the camel and could be usefully applied to other species at risk of orf infection.

Animals↗
PubMed1995

Rheumatoid factor, anti-heat shock protein (65 kDa) antibodies and anti-nuclear antibodies in equine joint diseases.

To consider the hypothesis that autoimmune mechanisms may contribute to the pathology of equine joint diseases, 3 autoimmune responses were assayed in sera and synovial fluids. IgM-rheumatoid factor and antibodies to heat shock protein 65 kDa were determined by ELISA; anti-nuclear antibodies were assayed by indirect immunofluorescence to whole cell nuclear components. All parameters showed only modest increases, if any and not in a pattern related to disease, although some statistically significant increases were detected. Group analysis showed significantly elevated synovial fluid IgM-rheumatoid factor (IgM-RF) in horses with OA (P < 0.01), traumatised joints (P < 0.01) and articular fractured bones (P < 0.001). There was no significantly increased IgM-RF in the sera of horses with joint disorders compared to control horses. Significantly raised anti-heat shock protein molecular weight 65 kDa (HSP65) antibodies were only found in the synovial fluids of the horses with traumatised joints (P < 0.001). No correlations were found between the synovial fluid and sera levels of IgM-RF or anti-HSP65 antibodies. Synovial fluid anti-HSP65 antibody and IgM-RF levels positively correlated in the OCD (P < 0.001), fracture (P < 0.01) and synovitis (P < 0.05) groups. As antibodies to HSP65 correlated with IgG concentrations in synovial fluids, it is not possible to draw conclusions on HSP roles in joint disease pathogenesis. No serum anti-nuclear antibodies (ANA) were detected by immunofluorescence using rat liver and a human epithelial cell line (HEp-2) as substrates.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Acute arthritis of cats associated with feline calicivirus infection.

Twelve specific pathogen-free cats were infected either by intra-articular inoculation or by contact exposure to one of two strains of feline calicivirus (FCV), either F65, a field strain originating from an outbreak of lameness in a group of cats, or a vaccine strain. Following either route of exposure, both strains induced signs typical of FCV infection including oral and nasal ulceration, conjunctivitis and ocular discharge. These signs were of equal severity for both virus strains, but overall, following either route of infection, F65 induced more severe disease than the vaccine strain, with marked pyrexia, lethargy and lameness. Vaccine virus only induced a relatively mild lameness following intra-articular inoculation. Gross pathological and histopathological lesions were seen in some of the joints, but again changes were more severe in the F65-exposed cats. Virus was isolated from both normal and affected joints from both groups of F65-exposed cats, and from a joint from each cat inoculated intra-articularly with vaccine virus. Mild transient lameness was also seen in one of two control cats inoculated intra-articularly, but no pathological changes were seen or virus isolated from joints. A cDNA probe used in RNA dot blot hybridisation experiments was found to be specific and more sensitive than virus isolation in detecting FCV in selected tissues. This may be useful in future studies on the pathogenesis of FCV disease and in studies on viral persistence in FCV carriers.

Acute Disease↗
PubMed1994

Measurement of glycosaminoglycans and keratan sulphate in canine arthropathies.

Glycosaminoglycans (GAG) and keratan sulphate (KS) were measured in sera and synovial fluids from dogs with either osteoarthritis (OA) or rupture of the cranial cruciate ligament (CCL) and normal dogs. The dogs with OA had higher synovial fluid GAG levels (P < 0.002) and serum KS (P < 0.03) compared to the normal dogs. No significant differences in serum GAG were found in either group. In both OA and rupture of the CCL, GAG levels were increased in the synovial fluid from the affected joint compared with the clinically normal (inactive) contralateral joint. Neither GAG nor KS measurements correlated with serum and synovial fluid antibodies to collagen type II, synovial fluid white cell count or age of dog. It is unlikely that the measurement of these cartilage breakdown products is of value for diagnostic or prognostic use in canine arthropathies.

Analysis of Variance↗
PubMed1994

Hyaluronan in canine arthropathies.

Soluble hyaluronan (HA), which has been considered as a marker for joint disease in man, was measured in serum and synovial fluid (SF) from dogs with osteoarthritis (OA), rheumatoid arthritis (RA), and rupture of the cranial cruciate ligament (CCL) and from normal dogs (control). Dogs with OA and RA had significantly increased serum HA (P < 0.001) and decreased synovial fluid HA (P < 0.001), as did dogs with CCL rupture (serum, P < 0.05; synovial fluid, P < 0.005). In OA, HA was lower in the SF from the affected joint than in that from the clinically normal (inactive) contralateral joint; no such difference was seen in dogs with CCL rupture. Dogs with liver disease (portocaval shunts, viral infectious hepatitis, metastatic neoplasm and disease secondary to diabetes mellitus) had increased serum HA concentrations (P < 0.001). There was a significant overlap of HA values in the diseased and normal dogs. Therefore, it is unlikely that the measurement of this cartilage breakdown product would be of value for diagnosis or prognosis in canine arthropathies.

Animals↗
PubMed1994

Modification of macrophage -T cell interaction during infection of mice with Mesocestoides corti (Cestoda).

Peritoneal macrophages from Mesocestoides corti-infected mice showed a marked and progressive loss of ability to act as accessory cells for syngeneic Con A-stimulated mesenteric lymph node lymphocytes. The same effect on the macrophages could be induced by intraperitoneal injection of M. corti culture supernatant, despite a concurrent increase in numbers of peritoneal adhesive macrophages. The findings are used to compare and contrast the known immunomodulatory effects of M. corti and taeniid metacestodes, the latter differing chiefly in their potential for modifying T-cell as well as macrophage behaviour.

Animals↗
PubMed1994

Level of nutrition and age at weaning: effects on humoral immunity in young calves.

Thirty-two calves were studied to determine the effects of level of nutrition (400 and 1000 g (air-dry matter) milk substitute per d) and age at weaning (5, 9 and 13 weeks) on humoral immune responses measured in serum and bronchoalveolar washings (BAW). All calves were immunized with Keyhole limpet haemocyanin (KLH) at 3 weeks of age, and with horse erythrocytes (HRBC) 1 d after weaning. Feeding the higher level of nutrition compared with the lower level decreased anti-HRBC titres and serum IgG2 and IgA responses to KLH (P < 0.05). Weaning at 5 compared with 9 weeks of age decreased serum anti-HRBC responses (P < 0.05), but weaning age had no effect on anti-KLH responses (P > 0.05). Feeding the higher level of nutrition increased total protein (P < 0.05) and IgG2 concentrations (P < 0.01) in BAW. The results showed that variation in husbandry conditions that is within conventional limits affects humoral immune responses in young, artificially-reared calves.

Aging↗
PubMed1994

Immune responses to canine distemper virus in joint diseases of dogs.

Measurement of immune complexes, antibodies against canine distemper virus (CDV) and anti-CDV antibodies in immune complexes were made in sera and SF from 'normal' dogs and from dogs with joint diseases. These data were compared with cytological analyses of SF samples. In dogs with canine rheumatoid-like arthritis (CRA) there were correlations between circulating anti-CDV antibody levels and circulating immune complex levels (P < 0.001) and between SF anti-CDV antibody levels and SF immune complex levels (P < 0.01). Furthermore, the SF PMN count in dogs with CRA correlated with both the SF anti-CDV antibody levels (P < 0.001) and the SF immune complex anti-CDV antibody levels (P < 0.001). The results demonstrated a relationship between CDV and ongoing synovial inflammation in dogs with CRA.

Animals↗
PubMed1994

Borrelia burgdorferi infection in UK horses.

Antibody levels (IgG and IgM) to Borrelia burgdorferi were measured in the sera and synovial fluids of UK horses. Western blotting against B. burgdorferi was also used on samples from seropositive horses. A low incidence of seropositivity was shown in horses from most parts of the UK. This increased in areas that have a high incidence of human and canine borreliosis (Norfolk and south coast). Leptospira infections of horses did not cause cross reactions in the B. burgdorferi ELISA. Most horses did not display clinical signs of Lyme disease. As with dogs and man, it is apparent that B. burgdorferi infection occurs in horses in the UK but clinical Lyme disease is uncommon.

Animals↗