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61.
Trans-10, cis-12 conjugated linoleic acid (t10c12-CLA) has been reported to enhance phagocyte function. Clostridium difficile toxin B (TcdB) has been known to inhibit Ras-homologous (Rho) guanosine triphosphatases (GTPases) which play essential roles in neutrophil immune functions. Here, we examined whether in vitro treatment with t10c12-CLA modulates the filamentous actin (F-actin) polymerization, phagocytic capacity, and oxidative burst activity (OBA) of canine peripheral blood polymorphonuclear neutrophilic leukocytes (PMNs) exposed to TcdB. Treatment with t10c12-CLA, but not linoleic acid, enhanced PMN F-actin polymerization, phagocytic capacity, and OBA, while TcdB suppressed these functions. t10c12-CLA reversed the suppressive effects of TcdB on these PMN functions. t10c12-CLA stimulated F-actin polymerization regardless of whether phagocytosis was stimulated by microspheres but only elevated OBA when microspheres were added. We asked whether the effects of t10c12-CLA were associated with changes in the activation of the Rho GTPase Cdc42. Treatment with t10c12-CLA augmented Cdc42 activity in both TcdB-treated and TcdB-naive PMNs during phagocytosis. Thus, t10c12-CLA up-regulates PMN phagocytic responses attenuated by TcdB. This effect is associated with an increase in actin polymerization and may involve the activation of Cdc42.  相似文献   
62.
63.
Depletion in the number of lymphocytes and viral persistence are thought to be the most important outcomes of classical swine fever virus (CSFV) infection. To define the change in peripheral blood mononuclear cells (PBMC) and virus replication in leukocytes after CSFV infection, 8-week old pigs were infected with the LPC vaccine strain or virulent CSFV (HCV-YL strain). Changes in the relative number of PBMCs were analyzed by flow cytometry. The results showed a significant increase in the relative percentage of monocytes in PBMCs during acute CSFV infection of naive pigs (p < 0.05). Monocyte frequencies were not changed in LPC-vaccinated pigs and control pigs. There was also a significant decrease in the number of IgM+ cells (p < 0.05) and a slight decrease in the number of CD4+ lymphocytes after 5 days of infection. There was no change in the frequency of CD8+ lymphocytes in PBMCs after infection. To define which subpopulation of PBMCs was the target for CSFV infection, PBMC populations from CSFV infected pigs were separated and stained for virus antigen expression. Alveolar macrophages (AM) were also studied. The results showed that CSFV replicated in all PBMC subpopulations: CD4+, CD8+, and IgM+ lymphocytes, and monocytes as well as AMs. However, virus antigen expression was more intense in monocytes and AMs. The infection of lymphocytes may, therefore, contribute to the depletion in their numbers after infection and lead to defective antibody production during virulent CSFV infection.  相似文献   
64.
We compared the immunoreactivity and numbers of tyrosine hydroxylase (TH) immunoreactive neurons and neuropil in the paraventricular nucleus (PVN) of the hypothalamus between the seizure sensitive (SS) and seizure resistant (SR) gerbils. The distributional pattern of TH immunoreactivity was similar in both groups: TH immunoreactivity was seen mainly in magnocellular neurons of the PVN. However, total TH immunoreactivity in the neurons and neuropil in the SS gerbils was significantly lower than that in the SR gerbils. In addition, the number of TH immunoreactive neurons in the SS gerbils was also much lower than those in the SR gerbils. These results indicate that SS gerbils have a low TH immunoreactivity in the hypothalamic PVN compared with that in SR gerbils.  相似文献   
65.

Background

Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, there is little metabolic profile data available about Korean Hanwoo cows. Therefore, this study aimed to determine the reference intervals of metabolic profile for Korean Hanwoo cows.

Methods

Healthy animals (2,205) were selected and divided into early (day 1 to 95), middle (day 96 to 190) and late (day 191 to 285) period according to their gestating period. Metabolic profile including total protein (TP), albumin (Alb), urea (UREA), glucose (Glu), total cholesterol (T-Cho), long-chain fatty acid (LCFA), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), creatinine (Crea), calcium (Ca), inorganic phosphorous (iP) and magnesium (Mg) were analyzed using a TBA-40FR automatic biochemical analyzer. The data of Korean Hanwoo cows were then compared to those of the Japanese Wagyu cows.

Results

Most of the data of the Korean Hanwoo cows were relatively higher than those of Japanese Wagyu cows, with the exception of Glu and GGT. This may indicate that the nutritional level of feed for the Korean Hanwoo cows was higher than that of the Japanese Wagyu cows because of the different feeding system. In particular, relatively higher levels of UREA and LCFA were observed in the Korean Hanwoo cows, and this may also contribute to the low reproduction efficiency.

Conclusions

These findings may provide some theoretical basis for understanding the reproductive and feeding situation of Korean Hanwoo cows.  相似文献   
66.
Equine body temperature taken with a non-contact infrared thermometer (NCIT) does not correlate well with the equine body temperature taken with a digital rectal thermometer (DRT), when it comes to absolute temperatures. There is significant variation in body temperature readings depending on the site at which the temperature was taken. NCIT may still may have, in that it does seem to be able to reliably detect when temperatures are more than that which is clinically normal, and does not seem to give falselyelevated readings in clinically normal horses. In horses that resent having their temperatures taken rectally, the NCIT seems to offer the equine clinician a quick and easy way to at least determine whether the horse's temperature is at or more than normal, even if it does not agree with DRT results.  相似文献   
67.
Recombinant fowlpox virus (rFPV/HN) expressing Newcastle disease virus (NDV) HN gene and rFPV/HN/chIL-12 co-expressing chicken IL-12 (chIL-12) and HN (rHN/chIL-12) genes have been characterized. rHN/chIL-12 or rchIL-12, expressed by our previous construct rFPV/chIL-12, co-administered with rHN was assessed for adjuvant activities of chIL-12. Chickens were vaccinated with various amounts of rHN/chIL-12 mixed with mineral oil (MO), intramuscularly. Levels of hemagglutination-inhibition (HI) antibody production depended on the concentration of the injected rHN or rHN/chIL-12. The lower HI antibody titers were obtained in chicken groups rHN/chIL-12/7-rHN/chIL-12/9, receiving 60ng rHN/8ng chIL-12 with MO, 30ng rHN/4ng chIL-12 with MO or 15ng rHN/2ng chIL-12 with MO, respectively, compared to those in chicken groups rHN/7-rHN/9, receiving rHN with MO alone. However, chickens in group rHN/chIL-12/7 or rHN/chIL-12/8 and rHN with MO alone showed the same effective protection. Chicken group rHN/chIL-12/9 was even more protective than that in group rHN/9. When rchIL-12 was co-injected with 15ng rHN plus MO, chickens produced low levels of HI antibody titers; while higher levels of IFN-γ production and an effective protection rate (83%) were obtained. On the other hand, low levels of IFN-γ production and low protection response (50%) were obtained in chickens injected with rHN with MO alone. Taken together, when the concentration of rHN decreased to certain levels, rchIL-12 reduced HI antibody production. The increase in the induction of IFN-γ production might suggest the enhancement of the cell-mediated immunity which conferred the protection from the NDV challenge.  相似文献   
68.
Recently, isolation and in vitro culture of putative spermatogonial stem cells (SSCs) in the domestic cat have been conducted. However, the cellular niche conditions that facilitate the establishment and long‐term maintenance of feline SSCs (FSSCs) have not been described. Therefore, we investigated the type of feeder cells used to stimulate colony formation and growth of FSSCs among the various factors in the FSSC niche. Spermatogonial stem cells isolated from feline testes were cultured on mitotically inactivated testicular stromal cells (TSCs) derived from cats, dogs and mice, and mouse embryonic fibroblasts (MEFs). The formation and growth of colonies derived from SSCs cultured on each type of feeder cell were identified at passage 0, and the morphology, alkaline phosphatase (AP) activity and expression of SSC‐specific genes in surviving colonies were investigated at passage 4. Among these diverse feeder cells, TSCs from cat showed the greatest colony formation, growth and maintenance of FSSCs, and SSC colonies cultured by passage 4 showed a typical dome‐shaped morphology, AP activity and expression of SSC‐specific genes (NANOG, OCT4, SOX2 and CD9). Accordingly, these results demonstrate that feline TSCs could be used as feeder cells to support the establishment and maintenance of SSCs from domestic cats.  相似文献   
69.
This study identifies and compares the kinematic gait changes occurring in tibial plateau levelling osteotomy (TPLO) and cranial tibial wedge osteotomy (CTWO) limbs after transection of the cranial cruciate ligament (CrCL). Ten, healthy, adult beagle dogs were assigned to TPLO (five dogs) and CTWO (five dogs) groups. Hind limb kinematics were assessed, while dogs were trotted at speeds ranging from 2.0 to 2.3 m/s. The animals were evaluated preoperatively (prior to TPLO and CTWO surgery) and at both 8 and 12 weeks after surgery. Two-dimensional evaluation was synchronized to obtain the three-dimensional coordinates using the APAS motion analysis software. Gait patterns were assessed by measuring stifle, tibiotarsal joint angles and stifle joints angular velocity. Stifle and tibiotarsal joint functions were not affected by TPLO surgery, but stifle and tibiotarsal joint angles were changed, following CTWO surgery, compared with their preoperative values. The angular velocity patterns of CTWO were characterized by increased stifle joint extension velocity from the middle to end swing phase and decrease in the peak velocities (flexion) during swing phase. None of these changes was observed in the stance phase after the CTWO surgery. These kinematic results showed that dogs that underwent a CTWO procedure were more likely to have significantly hyperextended gait patterns of the swing phase postoperatively than the dogs that had a TPLO procedure for repair of a ruptured CrCL.  相似文献   
70.
This study compared the performance of female Holstein calves fed either whole milk (WM) or milk replacer (MR) having similar gross composition to WM. Calves (n = 20) were separated from their mothers within 2 h of birth, weighed, moved into individual pens, and fed colostrum (10% of their BW over 2 feedings daily) for the first 3 d. Calves were alternately assigned to either WM (n = 10) or MR (n = 10) and were fed using mobile plastic bottles. At each feeding, diluted MR was prepared in buckets by mixing 0.143 kg of MR powder (as-is basis) in 1 L of lukewarm water. Calves on both treatments were fed (1.8 L/feeding) for 4 times daily for the first 25 d of age. Feeding frequency was reduced to 3 times daily for next 5 d, then to 2 times daily for next 14 d, and then to once daily during the last 5 d of the preweaning period. Feed intake, growth, and health variables were monitored until calves were 70 d of age. Mean daily consumption of WM and MR was similar in both treatment groups (P = 0.74). Initial BW of calves fed either WM or MR was similar (42.1 +/- 3.3 vs. 41.9 +/- 2.9 kg, respectively; P = 0.83). Calves fed WM or MR daily consumed similar amounts of calf starter (1,019 vs. 1,056 g, respectively; P = 0.32), hay (121.5 vs. 126.3 g, respectively; P = 0.30), and water (5.2 vs. 5.0 kg, respectively; P = 0.54). At weaning (d 49) and postweaning (d 70), BW was greater (P = 0.03 and P = 0.02, respectively) in calves fed WM than in those fed MR. Mean DMI from both solid and liquid feeds was not affected by the treatments during the preweaning (P = 0.21) and postweaning (P = 0.16) periods. Body weight gain efficiency during preweaning and overall was improved (P = 0.001 and P = 0.002, respectively) in calves fed WM than in those fed MR. Health (days scoured, rectal temperature, respiratory score, and general appearance score) and serum chemistry variables (glucose, total protein, urea N, nonesterified fatty acids, and creatinine) in calves were not affected (P >or= 0.12 and P >or= 0.12, respectively) by the treatments. Even though gross composition of the MR and WM was similar, growth was greater in calves fed WM. Calves fed WM consumed similar amounts of DM and were heavier than those fed MR, probably because of better bioavailability (digestion and assimilation) of nutrients and availability of some unknown growth factors from WM.  相似文献   
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