Study on the pathogenesis of foreign body granulomatous inflammation in the livers of sprague-dawley rats

Focal granulomatous inflammation developed in the livers of five 10-week-old male Sprague-Dawley rats. The characteristic features of this lesion were the presence of foreign body multinucleated giant cells engulfing calcium deposits and site-specific development in a fissure formed in a sub-lobation in the left lobe or interlobar fissure of the medial lobe of the liver. To clarify the pathogenesis of this lesion, rat livers showing abnormal sub-lobation or lobar atrophy, rat livers in an acute dermal toxicity study and guinea pig livers in a skin sensitization test were also examined histologically. Consequently, the present lesion was considered to be a reactive change against calcium that was dystrophically deposited in the area of hepatocellular necrosis due to delayed circulatory disturbance caused by external pressure or extension force. Granulomatous lesions like in the present cases should be differentiated from those caused by evident exogenous pathogens such as chemicals or microorganisms.     

Influence of parity and litter size on gestation length in beagle dogs

This study was conducted to investigate the effects of parity and litter size on gestation length in beagle bitches. The mean duration of the initial elevation (>2 ng/mL) in progesterone concentrations after the onset of proestrus was shorter (P < 0.05) in bitches without (nulliparous) whelping experience than in bitches with (multiparous) whelping experience (6.9 d versus 8.0 d). When calculated as the interval between the day of initial elevation in progesterone concentrations and the day of whelping, the gestation length in the nulliparous bitches was noted to be similar to that in the multiparous bitches (64.3 d versus 64.2 d). No significant correlation between gestation length and litter size was observed in any of the bitches. Our results indicate that the gestation length in beagle bitches is not affected by parity or litter size.     

High nitrate reductase activity in sprouts of Phyllostachys pubescens

We investigated the distribution of nitrate reductase activity (NRA) among leaves, roots, culms, twigs, sprouts, culm sheaths, and new leaves of Phyllostachys pubescens Mazel in May, when many sprouts emerge above ground and new leaves of adult culms expand. We found that the NRA differed among parts, and that sprouts showed high NRA. These results indicate that different tissues of P. pubescens vary in nitrate reduction, and sprouts possess high nitrate reduction capacity. We also found that culm sheaths showed high NRA, indicating that they have a high potential for nitrate reduction, even though they are shed in the way of sprout growth.     

Control of the collagen fibril diameter in the equine superficial digital flexor tendon in horses by decorin

The distribution pattern of collagen fibril diameter in the equine superficial digital flexor tendon (SDFT) is known to differ in central and peripheral areas of some regions. This study reports the essence of collagen fibril differences among different regions of the equine SDFT by transmission electron microscopic (TEM) and high-voltage electron microscopic observations and biochemical analysis. The distribution of large collagen fibrils increased but the density of collagen fibrils decreased from the proximal metacarpal region to the distal metacarpal region. Large collagen fibrils with an irregular cross-sectional profile were found more frequently in the middle metacarpal region than in other regions. Three-dimensional reconstruction of images of irregularly shaped collagen fibrils revealed that these fibrils are formed through fusion of small collagen fibrils with large ones. The amount of decorin, which reportedly inhibits the lateral fusion of collagen fibrils, decreased in the direction of the distal metacarpal region. On the other hand, the size of decorin gradually increased in the direction of the distal metacarpal region. These results suggest that regional differences in collagen fibril distribution and density of collagen fibrils in the SDFT are due, at least in part, to fusion of collagen fibrils and the concomitant regional differences in the amount and size of decorin.     

Assessment of the effects of exogenous long-acting insulin on glucose tolerance in alpacas

OBJECTIVE: To evaluate the effects of long-acting insulin on glucose clearance in alpacas. ANIMALS: 8 adult castrated alpacas. PROCEDURE: On 2 days, food was withheld from alpacas for 8 hours. Alpacas were randomly allocated to receive an SC injection of long-acting insulin (0.4 U/kg) or saline (0.9% NaCI) solution 1 hour before the first of 3 administrations of glucose (at 60, 480, and 1,200 minutes after treatment) on day 1 and the alternate treatment and procedure on day 2. Plasma glucose concentration was determined before and 15, 45, 120, and 240 minutes after each glucose administration, and fractional turnover rates were calculated. The data were compared between alpacas with and without insulin administration and among the 3 glucose administrations for each day. RESULTS: Compared with sham-treated alpacas, insulin-treated alpacas had significantly lower blood glucose concentrations from 180 to 600 minutes after treatment; they also had glucose concentrations significantly below baseline values from 120 to 480 minutes, at which time the mean glucose concentration was in the hypoglycemic range. Also, mean fractional turnover of glucose was significantly higher in insulin-treated alpacas from 105 through 300 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with known effects of regular insulin in alpacas, the action of long-acting insulin was of slower onset but longer lasting; its administration may induce hypoglycemia, even in alpacas that receive glucose. To maintain the hypoglycemic effect, long-acting insulin may have to be administered more than once daily and blood glucose concentration should be monitored to avoid hypoglycemic complications in alpacas.     

Development of an ELISA based on the baculovirus-expressed capsid protein of porcine circovirus type 2 as antigen

The genome of porcine circovirus type 2 (PCV2) contains two major open reading frames, which have been shown to encode the virus capsid and replication-associated proteins. The capsid protein is a major structural protein of the virus; it can be a suitable target antigen for detecting PCV2-specific antibodies to monitor PCV2 infection. To produce the antigen, the capsid protein coding sequence was cloned into a baculovirus transfer vector, and a recombinant capsid (rC) protein of PCV2 was expressed as a combined fusion protein in frame with a C-terminal peptide of six histidines. The affinity-purified rC protein was used as coating antigen to develop an ELISA for detecting the virus-specific antibodies in swine sera. The rC protein-based ELISA (rcELISA) was evaluated by examining a panel of 49 PCV2-positive and 49 PCV2-negative swine sera. In comparative experiments of immunoperoxidase monolayer assay (IPMA) using 102 field sera, there was 89.2% coincidence between data obtained by the rcELISA and IPMA. The rcELISA achieved 88.5% specificity and 89.4% sensitivity for detection of PCV2 antibody in the field sera. The assay showed no cross-reactivity with antibodies to PCV type 1, porcine reproductive and respiratory syndrome virus and porcine parvovirus. The results suggest that the rcELISA is suitable for routine serodiagnosis and epidemiological surveys of PCV2-associated diseases.