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51.
To clarify the relationship between cellular immune status and nutritive condition in periparturient dairy cows, feeding content, blood profiles, and immune condition were observed in cows from two dairy herds with different types of feed content. Immunological analyses such as leukocyte population and peripheral blood mononuclear cell (PBMC) mRNA of IFN-gamma, TNF-alpha, IL-4, and IL-10, quantified by real-time RT-PCR were performed. With regard to feed content during dry periods, there were six cows in the herd with insufficient non-structural carbohydrate (NFC) intake (group I) and six cows in the herd with sufficient NFC intake (group II). Significantly lower levels of blood glucose were observed in group I between weeks -12 and 16 compared with group II. Serum cholesterol level was significantly lower in group I between weeks 2 and 10 than in group II. The numbers of CD3+ and CD4+ T cells in group I were significantly lower than those in group II in weeks 6 and 14. The numbers of CD21+ B cells were significantly lower in group I than in group II in weeks -16, -12, 2, and 10. On the other hand, the CD4+/CD8+ ratio in group II was significantly higher than group I between weeks 2 and 14. The IFNgamma/IL-4 mRNA rate in group I was significantly lower than group II in week 6. We concluded that cellular immune depression occurrs after calving in dairy cows with low nutritional status in the periparturient period.  相似文献   
52.
The complementary DNAs of the Th1 (IL-2, IL-12p35, and IFN-gamma) and Th2 (IL-4, IL-10 and IL-13) cytokine genes of the bactrian camel (Camelus bactrianus) were cloned, sequenced, and analyzed. IL-2, IL-4, IL-10, IL-12p35, IL-13, and IFN-gamma were found to have 465, 402, 537, 669, 411, and 501 bp length open reading frames with 154, 133, 178, 222, 136, and 166 amino acid encodings, respectively. The homology ranged from 58.8% to 100% between the nucleotide sequences of the camel cytokine genes and the published sequences of other mammalian genes, including the llama, pig, cow, horse, human, and mouse. The cDNA had highest homology with orders Artiodactyla (pigs and cattle) and Perissodactyla (horses), especially to the recently cloned llama sequences.  相似文献   
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54.
A 7-year-old, male, mixed breed dog was referred to the Veterinary Teaching Hospital at Kitasato University because of anorexia, lameness and multiple cutaneous lesions. Observation of bone marrow plasmacytosis, osteolytic bone lesions, serum myeloma protein and cutaneous infiltration of myeloma cells led us to a diagnosis of multiple myeloma (MM) with cutaneous involvement. Polymerase chain reaction and sequence analysis for the rearranged genes of immunoglobulin and T-cell receptor demonstrated that the neoplastic cells found in skin lesions or bone marrow are of B-lymphocyte lineage and share a common original precursor cell. The dog was treated with UW-Madison protocol or melphalan/prednisone protocol and survived 175 days. This is rare case of anaplastic MM with cutaneous involvement in dog.  相似文献   
55.
Although the importance of carbohydrate recognition by sperm during egg zona pellucida binding has been widely reported, the sperm molecular species that recognize the carbohydrates are poorly characterized. Our previous cytochemical study indicated that two kinds of carbohydrate-binding proteins are expressed on porcine sperm heads-one recognizes N-acetyllactosamine (Galβ1-4GlcNAc-), and the other recognizes the Lewis X structure (Galβ1-4(Fucα1-3)GlcNAc-). For this report, we used proteomic techniques to characterize the sperm proteins that bind N-acetyllactosamine. Porcine sperm plasma membrane was solubilized with a detergent solution and subjected to sequential chromatography with dextran sulfate agarose, affinity, and hydroxyapatite, and the binding activities in the eluates were monitored by a solid-phase binding assay. The tryptic peptides of two proteins most likely associated with the binding activities were subjected to tandem mass spectrometry sequencing. A subsequent database search identified one of the two proteins as predicted disintegrin and metalloprotease domain-containing protein 20-like (XP_003128672). The other protein was identified as disintegrin and metalloprotease domain-containing protein 5 (AB613817) by database searches for homologous amino acid sequences, cDNA cloning, nucleotide sequencing and nucleotide database searches. Furthermore, two-dimensional blue native/SDS-PAGE demonstrated that they formed a variety of non-covalent complexes. Therefore, these ADAM complexes probably are responsible for the N-acetyllactosamine-binding activity. An affinity-purified fraction containing these ADAM complexes showed zona pellucida-binding activity, though the activity was relatively weak, and the presence of another zona pellucida-binding protein that probably works in concert with these ADAM complexes was suggested. Immunofluorescence testing suggested that ADAM20-like was localized on the anterior part of the sperm plasma membrane.  相似文献   
56.
Forty Caspian seals were surveyed seroepidemiologically between 1993 and 1998 around the times of mass mortality that occurred in 1997 in the Caspian Sea and seven Baikal seals were also surveyed in 1998. Virus neutralizing tests and ELISA clearly suggested that distemper virus epidemic was caused in Caspian seals before the spring of 1997 and that CDV infection continued to occur in Lake Baikal in recent years.  相似文献   
57.
Mycosporine-like amino acids (MAAs) are water-soluble UV-absorbing pigments, and structurally different MAAs have been identified in eukaryotic algae and cyanobacteria. In this study novel glycosylated MAAs were found in the terrestrial cyanobacterium Nostoc commune (N. commune). An MAA with an absorption maximum at 334 nm was identified as a hexose-bound porphyra-334 derivative with a molecular mass of 508 Da. Another MAA with an absorption maximum at 322 nm was identified as a two hexose-bound palythine-threonine derivative with a molecular mass of 612 Da. These purified MAAs have radical scavenging activities in vitro, which suggests multifunctional roles as sunscreens and antioxidants. The 612-Da MAA accounted for approximately 60% of the total MAAs and contributed approximately 20% of the total radical scavenging activities in a water extract, indicating that it is the major water-soluble UV-protectant and radical scavenger component. The hexose-bound porphyra-334 derivative and the glycosylated palythine-threonine derivatives were found in a specific genotype of N. commune, suggesting that glycosylated MAA patterns could be a chemotaxonomic marker for the characterization of the morphologically indistinguishable N. commune. The glycosylation of porphyra-334 and palythine-threonine in N. commune suggests a unique adaptation for terrestrial environments that are drastically fluctuating in comparison to stable aquatic environments.  相似文献   
58.
Using microPET and (18)F-fluorodeoxyglucose ((18)F-FDG) as a tracer, we investigated regional brain activation in a rat model of visceral hypersensitivity induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). TNBS injection into the proximal colon through laparotomy resulted in a significant, sustained decrease in the pain threshold to mechanical distention of the distal colon, indicating a phenomenon referred to as visceral hypersensitivity. When TNBS-induced colonic hypersensitivity was fully developed, all the TNBS-treated rats presented characteristic pain behaviors in response to colonic distention at previously innocuous pressure (0-35 mmHg) that produced no abdominal pain in sham-operated control animals. In microPET study, colonic distention at the normally non-painful pressure produced significant increases in (18)F-FDG uptake in the thalamus and sensory cortex I of TNBS-treated rats. Since the increases in (18)F-FDG uptake in the brain regions were completely abolished by an analgesic dose of morphine (375 microg/kg, s.c.), it is most likely that the regional brain activation detected by microPET is a pain-related central event. The pharmacological and microPET data indicate that colonic distention at the normally non-painful pressure activates specific brain regions in rats with TNBS-induced visceral hypersensitivity, and the microPET protocol described here could provide an objective measure to test visceral analgesic compounds.  相似文献   
59.
At least two biotypes were observed at the 2nd passage stage after the isolation of Foot-and-mouth disease Virus (FMDV) O/JPN/2000 strain. These 2 types of viruses differed from their plaque phenotypes and were distinguishable by using a monoclonal antibody (MAb) 64G8 that was made for the FMDV O/JPN/2000 strain. One of these 2 biotypes formed small plaque (SP) and with immuno staining showed a positive reaction to MAb 64G8, while the other formed clear large plaque (LP) and did not react with MAb 64G8. The amino acid sequences of the capsid coding region (VP1-VP4) of the SP virus (SPV) and the LP virus (LPV) revealed two substitutions on the 133rd amino acid in VP2, and the 56th amino acid in VP3. These amino acid changes of SPV and LPV are Asn to Asp, Arg to His, respectively. The Arg of the 56th amino acid in VP3 that have been known as critical position of cell culture adapted virus. Only LPV showed high pathogenicity in suckling mice, and its LD(50) was calculated to be about 10(2) TCID(50)/0.1 ml. These results showed that the SPV that existed at the 2nd passage stage from isolation was a low virulence virus, which may suggest why the pathogenicity of O/JPN/2000 did not show clear symptoms in infected cattle.  相似文献   
60.
Three rumen‐protected lysine (RPL) products (AjiPro®‐L, LysiPEARLTM, and Feedtech Bypass LysineTM: A, B, and C, respectively) were tested for stability in two forage‐based total mixed rations (TMR1, 41.3% dry matter (DM), and TMR2, 49.5% DM) (experiment 1) and for Brix value (experiment 2). In experiment 1, each RPL product (2 g each) and TMR diet (200 g) were mixed and stored in plastic bags at 20°C for 0, 1, 3, 6, 12, 24, and 48 hr. In experiment 2, each RPL product (2 g) was dispensed into ion‐exchanged water (20 ml) and kept at 20°C for 0, 0.5, 1, 3, 6, 12, 24, and 48 hr. At each time point, free lysine (Lys) content and Brix values of extracts were measured, and Lys release (LR, %) was calculated. All RPL products LR% varied with varying diets DM and increased with increasing of time exposed to diets; it was highest in C, followed by B, and then A. Water LR% positively correlated with that from diets and with Brix values of Lys dissociated in water. Our results indicated that Lys dissociation from RPL products is affected by diet DM content. Brix value may be used as a potential marker for RPL protection efficacy.  相似文献   
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