Chemical modification of wood by non-formaldehyde cross-linking reagents

Summary The probability of bond between wood components and glyoxal was examined by means of a mechanical method, infrared (IR) spectrometry, and solid state ¹³C-nuclear magnetic resonance (NMR) spectrometry. The successive fixation of a compressed wood by the glyoxal treatment suggested the formation of cross-linkings between wood components and/or wood structures. The IR spectra showed that ester bond as well as ether bond was formed between wood components and glyoxal. The existence of linkages between glyoxal and cellulose was indicated also from the NMR spectra. The addition of glycol to the glyoxal solution was investigated from the viewpoint of stabilizing effect of the linkages. When 0.2 mole ratio of glycol was added to 5–10% glyoxal solution, weight gain and antiswelling efficiency (ASE) were largest, however the addition of excessive amount of glycol did not advance further the weight gain and ASE. When an appropriate amount of glycol was added to the impregnation solution, both weight and ASE did not largely reduce even by the repeated hot water soaking. By the treatment without glycol, the dimensional stability after water soaking was attributed to only restraint of the swelling. On the other hand, when the glycol was added, the dimensional stability was developed not only by the restraint of the swelling but also by the buckling effect.We would like to thank Associate Professor Dr. Umezawa, Wood Research Institute, Kyoto University, for his invaluable support in NMR analysis. Thanks are also due to Dr. Inoue, Wood Research Institute, Kyoto University, for his preparing the wood specimens.     

Effect of prophylactic administration of hyperimmune plasma to prevent Rhodococcus equi infection on foals from endemically affected farms

The effect on foals of prophylactic administration of hyperimmune plasma to prevent R. equi infection was investigated on three farms at which R. equi infection was endemic. Sixteen foals between 10 and 39 days of age were intravenously given 1-21 of hyperimmune plasma. ELISA antibody titres against R. equi were significantly increased and maintained at high levels for over 30 days in most of the recipient foals. The prevalence of R. equi infection was 6.3% (1/16) in the foals that received the immune plasma, and 26.3% (5/19) in the control foals not given the immune plasma on the three farms. For 2 years before and after this field trial on the three farms, 18 of 64 foals (28.1%) showed clinical signs of respiratory tract infection and four of them died of R. equi pneumonia. Heavy contamination of horses and their environment with virulent R. equi was detected by colony blotting, and plasmid profiles also suggested that foals on the three farms were constantly exposed to virulent R. equi. The results of this field trial support previous observations by some researchers that the administration of hyperimmune plasma to foals in the early days of life promotes prevention of R. equi infection on endemic farms; however, the mechanism of hyperimmune plasma protection remains unclear.     

Hepatic lesions caused by migrating larvae of Ascaris suum in chickens

Group A consisted of chickens infected with a single dose of Ascaris suum and group B of chickens infected with two successive doses. At days 1, 3, 7, 14 and 21 after the first or second infection dose, six chickens from each group were sacrificed. In both groups, larvae were recovered from the livers on days 1, 3, and 7 and lungs on days 3 and 7. No larvae were detected in chickens on day 14. Clear white lesions were noticed only on the livers from chickens of group B at day 7 but had disappeared at day 14. A comparison with group B showed mild histological changes that developed relative to the livers from group A.     

Bovine spongiform encephalopathy (BSE) safety measures in Japan

Since the first identification of bovine spongiform encephalopathy (BSE) in Japan in September 2001, a series of safety measures was introduced by the Ministry of Agriculture, Forestry and Fisheries, the Ministry of Health, Labour and Welfare and the Food Safety Commission of the Cabinet Office. These measures included blanket BSE testing and removal of specified risk materials at slaughterhouses, surveillance of risk animals and a ban on the use of meat-and-bone meals and traceability on all farms. The Japanese experience over the past five years has shed light on several issues in countries that have a low BSE incidence.     

Evaluation of left ventricular Tei index (index of myocardial performance) in healthy dogs and dogs with mitral regurgitation

The left ventricular (LV) Tei index (index of myocardial performance) has been demonstrated to be clinically useful in estimating comprehensive LV function, including the systolic and diastolic performances, in various human cardiac diseases. The purposes of this study were to validate the correlation between the LV Tei index and LV function obtained by cardiac catheterization in healthy dogs, and to evaluate the LV Tei index in dogs with naturally occurring mitral regurgitation (MR). In healthy dogs, the LV Tei index was significantly correlated with the LV peak +dP/dt (r = -0.89) and LV peak -dP/dt (r=0.87). The LV Tei index significantly increased in dogs with MR compared with normal dogs and significantly increased with progressively more severe clinical signs due to heart failure. The elevation of the LV Tei index in dogs with symptomatic MR appears to be associated with shortening of ejection time. The LV Tei index significantly increased with age and was not correlated with heart rate and body weight in normal dogs. In conclusion, our study demonstrated that the LV Tei index was measurable in dogs and not influenced by heart rate and body weight. The LV Tei index significantly increased with the progression of clinical signs in MR dogs. In particular, the elevation of the LV Tei index in dogs with symptomatic MR due to shortening of ejection time may suggest LV systolic dysfunction and the decrement of forward stroke volume.     

Cutaneous pyogranuloma in a cat caused by virulent Rhodococcus equi containing an 87 kb type I plasmid

A 2-year-old intact male domestic shorthaired cat presented with a chronic, nodular, ulcerated, cutaneous lesion on the right thoracic limb. Histological and cytological examination revealed a pyogranulomatous inflammation with basophilic organisms in the macrophages. A virulent form of Rhodococcus equi containing an 87 kb type I (VapA) virulence plasmid was identified from cultures of biopsy samples. This report describes the clinicopathological features, plasmid profile and virulence of this case of R equi infection.     

Genotypic characterization of VapA positive Rhodococcus equi in foals with pulmonary affection and their soil environment on a warmblood horse breeding farm in Germany

Pulsotypes of VapA positive Rhodococcus equi isolated from foals and soil on a farm in Germany were characterized on the basis of nasal and tracheal samples simultaneously collected in 2003 from 217 foals with sonographic evidence of pneumonia or pulmonary abscesses. Of the 217 double samples, R. equi was isolated in 118 (54%) of the tracheal samples and in 52 of the nasal swab samples (24%) (P<0.001). Furthermore, 37 and 55 isolates were also randomly selected from nasal swabs and the tracheal samples, respectively, and further processed to determine the presence of VapA by colony blot enzyme-linked immunosorbent assay. This method showed that 26 (68%) of the nasal swabs and 40 (73%) of the tracheal samples were VapA-positive. R. equi was isolated from 56 (87%) of the 64 soil samples taken from the paddocks and stables in March and from 17 (68%) of the 25 samples taken in July of 2003. Three (21%) of these randomly selected 14 isolates from March and 13 (81%) of the 16 from July were VapA-positive. The VapA positive isolates from foals and soil were genotyped by plasmid profiling, restriction fragment length polymorphism analysis and pulsed-field gel electrophoresis. Of the 83 isolates, 80 contained an 85-kb type I plasmid and three contained an 87-kb type I plasmid. Pulsed-field gel electrophoresis yielded four distinct VspI profiles dividing 83 isolates into three major (A1, 51; D, 14; and 11 isolates) and three minor (C, 4; A3, 2; and A2, 1 isolates) groups. These results suggest that the majority of foals were exposed to and infected with three pulsotypes of VapA positive R. equi containing an 85-kb type I plasmid.     

Evaluation of fecal samples from mares as a source of Rhodococcus equi for their foals by use of quantitative bacteriologic culture and colony immunoblot analyses

OBJECTIVE: To determine whether mares are a clinically important source of Rhodococcus equi for their foals. SAMPLE POPULATION: 171 mares and 171 foals from a farm in Kentucky (evaluated during 2004 and 2005). PROCEDURES: At 4 time points (2 before and 2 after parturition), the total concentration of R equi and concentration of virulent R equi were determined in fecal specimens from mares by use of quantitative bacteriologic culture and a colony immunoblot technique, respectively. These concentrations for mares of foals that developed R equi-associated pneumonia and for mares with unaffected foals were compared. Data for each year were analyzed separately. RESULTS: R equi-associated pneumonia developed in 53 of 171 (31%) foals. Fecal shedding of virulent R equi was detected in at least 1 time point for every mare; bacteriologic culture results were positive for 62 of 171 (36%) mares at all time points. However, compared with dams of unaffected foals, fecal concentrations of total or virulent R equi in dams of foals with R equi-associated pneumonia were not significantly different. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that dams of foals with R equi-associated pneumonia did not shed more R equi in feces than dams of unaffected foals; therefore, R equi infection in foals was not associated with comparatively greater fecal shedding by their dams. However, detection of virulent R equi in the feces of all mares during at least 1 time point suggests that mares can be an important source of R equi for the surrounding environment.     

Clinical significance of circulating vascular endothelial growth factor in dogs with mammary gland tumors

Increase in circulating vascular endothelial growth factor (VEGF) is suggested as a prognostic indicator in human patients with malignant tumors. The purpose of this study was to evaluate the clinical significance of circulating VEGF in dogs with mammary gland tumors (MGT). Both plasma and serum VEGF were significantly higher in dogs with MGT when compared with those in the healthy dogs. In dogs with MGT, the plasma and serum VEGF of the malignant group increased significantly compared with those of the benign group. Additionally, there was a significant difference between the plasma and serum VEGF in the groups with postoperative metastasis and no metastasis. Circulating VEGF is expected to be clinically available for the determination of prognosis in canine MGT.