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991.
This study was designed to evaluate the effect of oral tolerance of caseins (CSN) and whey proteins (WP) in alleviating the allergic response to cow's milk proteins in Swiss albino mice raised on a milk protein–free diet. Oral tolerance was induced by feeding mice with 20 mg of CSN or WP once in a day for 4 days consecutively before immunization with respective protein by intraperitoneal (i.p.) injections (20 μg 200 per μl of PBS) using 2% of alum Al(OH)3 as adjuvant. Three weeks later, oral tolerance induction was analysed in humoral and cellular compartments of CSN‐ and WP‐fed versus saline‐fed control mice groups by measuring seric and intestinal antibody responses, mRNA abundance in splenic tissue and cytokine secretion patterns. The specific serum immunoglobulin‐E (IgE) levels were significantly suppressed (p < 0.05), while sIgA was enhanced in these groups when compared with their respective saline‐fed mice. Moreover, the mRNA levels of interferon‐γ (IFN‐γ) and interleukin‐4 (IL‐4) in both CSN‐ and WP‐tolerized mice were found to be significantly decreased, while the abundance of interleukin‐10 (IL‐10) and transforming growth factor‐β (TGF‐β) was increased significantly, as compared to respective control groups. Finally, cytokine profiles indicated a reciprocal decrease in IL‐4 and IFN‐γ versus an increase in IL‐10 secretions in supernatants of cultured splenocytes of tolerized mice. Taken together, these results clearly showed that oral administration of cows' milk caseins and whey proteins can induce significant hyposensitization in mice, with the participation of suppressor cytokines.  相似文献   
992.
The arterivirus porcine reproductive and respiratory syndrome virus (PRRSV) contains six structural proteins the roles of which are not completely understood. In a preceding study, immunization with the dutch isolate I10 of PRRSV had led to the development of MAbs against four structural proteins [Wieczorek-Krohmer, M., 1994. Herstellung und Charakterisierung von monoklonalen Antik?rpern gegen das Virus des Porzinen Reproduktiven und Respiratorischen Syndroms (PRRSV). Inaugural-Dissertation, Ludwig-Maximilians-Universit?t, München] here finally identified by reaction with individual plasmid-expressed PRRSV proteins as products of ORFs 3 (GP3), 4 (GP4), 5 (GP5) and 7 (N). Surprisingly, the MAbs against GP5 revealed the presence of two antigenically distinct virus populations in the isolate I10, the population PRRSV-'PPV', isolated from plaques and the PRRSV-'EPV', gained by end point dilution. MAbs against GP3, GP4 and N reacted with both I10 populations as well as with natural PRRSV isolates. However, the anti-GP5 MAbs exclusively recognized PRRSV-'PPV'. In this study immunization of mice with both separated I10 populations confirmed that solely PRRSV-'PPV' possesses the property to induce an immune response ultimately leading to the establishment of MAbs against GP5. Whereas the 15 anti-GP5 MAbs (derived from four independent fusions) reacted exclusively with PRRSV-'PPV' of the isolate I10, anti-GP4 MAbs detected their target antigen on various isolates of European origin and were able to neutralize them. As indicated by competition assays and selection of neutralization-resistant virus mutants, all GP5 MAbs are directed against a single antigenic site on the ORF 5 protein. Both groups of neutralizing antibodies bound to the surface of purified virions demonstrating that the recognized epitopes represent surface structures of the virion envelope. However, anti-GP5 MAbs mediated the binding of more gold granules than anti-GP4 MAbs. Comparison of the neutralizing effect of anti-GP4 and anti-GP5 MAbs revealed the anti-GP5 MAbs as the more efficient antibodies. For the complete neutralization of about 100 ID50 of PRRSV-'PPV' anti-GP5 culture supernatant was effective up to a dilution of 1:1280 whereas the most effective anti-GP4 antibodies exhibited a comparable effect only up to 1:64. These results indicate that PRRSV GP5 in principle is a major target for neutralizing antibodies, as is found for other arteriviruses, but that in nature 'ORF 5 escape mutants' may develop as easily as in vitro.  相似文献   
993.
The objective of this study was to develop prediction equations for estimating proportional carcass yield to a variety of external trim levels and bone-in and boneless pork primal cuts. Two hundred pork carcasses were selected from six U.S. pork processing plants and represented USDA carcass grades (25% USDA #1, 36% USDA #2, 25% USDA #3, and 14% USDA #4). Carcasses were measured (prerigor and after a 24 h chill) for fat and muscle depth at the last rib (LR) and between the third and fourth from last rib (TH) with a Hennessy optical grading probe (OGP). Carcasses were shipped to Texas A&M University, where one was randomly assigned for fabrication. Selected sides were fabricated to four lean cuts (ham, loin, Boston butt, and picnic shoulder) then fabricated progressively into bone-in (BI) and boneless (BL) four lean cuts (FLC) trimmed to .64, .32, and 0 cm of s.c. fat, and BL 0 cm trim, seam fat removed, four lean cuts (BLS-OFLC). Total dissected carcass lean was used to calculate the percentage of total carcass lean (PLEAN). Lean tissue subsamples were collected for chemical fat-free analysis and percentage carcass fat-free lean (FFLEAN) was determined. Longissimus muscle area and fat depth also were collected at the 10th and 11th rib interface during fabrication. Regression equations were developed from linear carcass and OGP measurements predicting FLC of each fabrication point. Loin muscle and fat depths from the OPG obtained on warm, prerigor carcasses at the TH interface were more accurate predictors of fabrication end points than warm carcass probe depth obtained at the last rib or either of the chilled carcass probe sites (probed at TH or LR). Fat and loin muscle depth obtained via OGP explained 46.7, 52.6, and 57.1% (residual mean square error [RMSE] = 3.30, 3.19, and 3.04%) of the variation in the percentage of BI-FLC trimmed to .64, .32, and 0 cm of s.c. fat, respectively, and 49.0, 53.9, and 60.7% (RMSE = 2.91, 2.81, and 2.69%) of the variation in the percentage of BL-FLC trimmed to .64, .32, and 0 cm of s.c. fat, respectively. Fat and loin muscle depth from warm carcass OGP probes at the TH interface accounted for 62.4 and 63.5% (RMSE = 3.38 and 3.27%) of the variation in PLEAN and FFLEAN, respectively. These equations provide an opportunity to estimate pork carcass yield for a variety of procurement end point equations using existing on-line techniques.  相似文献   
994.
Mutations within the growth hormone receptor (GHR) gene that lead to an inactivated or truncated GHR protein cause abnormal growth and small adult size in a variety of species (Laron dwarfism). We studied a line of miniature Bos indicus cattle that have phenotypic (small mature size) and endocrine (increased blood growth hormone and decreased blood insulin-like growth factor-I concentrations) similarities to Laron dwarfs. Liver mRNA from miniature and control cattle was used to amplify a cDNA within the coding region of the GHR. The miniature cattle had GHR mRNA size (determined by Northern blot) and cDNA sequence that were similar to control cattle and, therefore, were unlike most Laron dwarf genotypes in which the GHR gene is mutated. Amounts of mRNA from liver as well as muscle (superficial neck and longissimus) were analyzed by ribonuclease protection assay for IGF-I, total GHR, GHR 1A (inducible, liver-specific GHR mRNA), and GHR 1B (constitutive GHR mRNA). Four control and five miniature bulls were tested. As expected, liver IGF-I mRNA was decreased in the miniature cattle (approximately 12% of control; P < 0.01). The amount of the total GHR as well as GHR 1A mRNA were also decreased in liver (17% and 19% of control, respectively; P < 0.01). Other GHR mRNA, including GHR 1B mRNA, were similar for miniature and control cattle. In muscle, there was a tendency (P < 0.10) for decreased IGF-I mRNA and increased GHR mRNA in miniature compared with control cattle. In summary, a novel phenotype for Laron dwarfism in Bos indicus cattle was associated with underexpression of GHR 1A mRNA, but not other GHR mRNA variants in liver. In addition to decreased GHR 1A mRNA, the miniature cattle had decreased liver IGF-I mRNA. Full expression of GHR 1A in liver, therefore, may be required for full liver IGF-I expression and normal growth.  相似文献   
995.
不同非洲猪瘟病毒株j5R基因及其编码蛋白的比较   总被引:5,自引:0,他引:5  
根据非洲猪瘟病毒MalawiLIL20/1株j5R阅读框C端抗原决定簇序列制备的合成肽能被不同毒株感染康复猪的免疫血清识别。多聚酶链反应研究表明,9个不同毒株的j5R基因长度略有差异;蛋白转印杂交试验证明,这种基因长度的差异导致相应蛋白多肽的长度多样性。这些结果进一步证明,长度多样性是非洲猪瘟病毒基因及其编码蛋白较为普遍的特点。  相似文献   
996.
The aim of the monitoring of zearalenone presence in the blood plasma of women with neoplastic lesions in the reproductive tract was to asses whether the phytosteride is noted in the patients blood and whether the correlation exists between its presence and the incidence of particular neoplasm. The presence of zearalenone or its metabolite--alpha-zearalenole, was noted in 13.51% of the examined women. In 60% of the patients with the confirmed presence of the xenobiotic it was noted in the lowest concentrations. These patients had neoplastic lesions of Carcinoma corpus uteri type.  相似文献   
997.
Phenylbutazone (PBZ) is a nonsteroidal anti‐inflammatory drug used in the treatment of chronic pain and arthritis. Topical and transdermal administration of PBZ would be beneficial in large animals in terms of minimizing gastro‐intestinal ulcerations and other side effects, easy administration to legs and joints and minimizing the dose to reduce systemic toxicity of the drug. A topical liposomal preparation with different concentrations of a mono‐substituted alkyl amide (MSA) and PBZ was formulated. The formulations were evaluated by in vitro skin‐permeation kinetics through deer skin using Franz diffusion cells. By increasing drug loading from 1% to 5% w/w, the steady‐state flux (μg/cm2/h) of PBZ was increased twofold (P < 0.001). Similarly, by increasing the MSA concentration from 0% to 4%, the steady‐state flux (μg/cm2/h) of PBZ was increased twofold (P < 0.001). Overall, by increasing the drug load and the use of an appropriate amount of the penetration enhancer, the steady‐state flux of PBZ through skin was increased fourfold (P < 0.001). MSA at both 2% and 4% w/w concentrations significantly increased the skin levels of PBZ as compared with control (P < 0.05). In conclusion, MSA served as an effective skin‐penetration enhancer in the liposomal gel of PBZ for deer.  相似文献   
998.
Rat bite fever     
Rat bite fever (RBF) is a bacterial zoonosis for which two causal bacterial species have been identified: Streptobacillis moniliformis and Spirillum minus. Haverhill fever (HF) is a form of S. moniliformis infection believed to develop after ingestion of contaminated food or water.  相似文献   
999.
Over a 16-year period, 190 tumors and tumorlike lesions from 179 pet rabbits were submitted for histopathologic examination. A total of 23 different tumor types and 1 tumorlike lesion were diagnosed. The most common diagnoses were trichoblastoma, collagenous hamartoma, and Shope fibroma. Viral-induced tumors were Shope fibroma (19) and Shope papilloma (2). Common nonviral epithelial tumors included trichoblastoma (59), squamous cell carcinoma (5), squamous papilloma (4), trichoepithelioma (3), and apocrine carcinoma (3). Common mesenchymal tumors were lipoma (10), liposarcoma (3), myxosarcoma (9), malignant peripheral nerve sheath tumor (8), fibrosarcoma (7), and leiomyosarcoma (4). Malignant melanoma was diagnosed in 8 rabbits. Collagenous hamartomas were diagnosed in 26 rabbits. Mesenchymal proliferations occurred significantly more often in male rabbits than in females. Collagenous hamartomas and myxosarcomas occurred exclusively in male animals, and 3 rabbits had multiple collagenous hamartomas. Immunohistochemistry was applied in cases in which a definite diagnosis could not be reached on hematoxylin and eosin slides. Follow-up information was received in 19 cases. Carcinomas recurred (2 of 3) or metastasized (1 of 3), whereas sarcomas frequently recurred (7 of 12). One malignant melanoma (1 of 3) and one poorly differentiated round cell neoplasm recurred (1 of 1). This is the first comprehensive retrospective analysis on skin neoplasia in pet rabbits.  相似文献   
1000.
REASON FOR PERFORMING STUDY: West Nile virus (WNF) is a Flavivirus responsible for a life-threatening neurological disease in man and horses. Development of improved vaccines against Flavivirus infections is therefore important. OBJECTIVES: To establish that a single immunogenicity dose of live Flavivirus chimera (WN-FV) vaccine protects horses from the disease and it induces a protective immune response, and to determine the duration of the protective immunity. METHODS: Clinical signs were compared between vaccinated (VACC) and control (CTRL) horses after an intrathecal WNV challenge given at 10 or 28 days, or 12 months post vaccination. RESULTS: Challenge of horses in the immunogenicity study at Day 28 post vaccination resulted in severe clinical signs of WNV infection in 10/10 control (CTRL) compared to 1/20 vaccinated (VACC) horses (P<0.01). None of the VACC horses developed viraemia and minimal histopathology was noted. Duration of immunity (DPI) was established at 12 months post vaccination. Eight of 10 CTRL exhibited severe clinical signs of infection compared to 1 of 9 VACC horses (P<0.05). There was a significant reduction in the occurrence of viraemia and histopathology lesion in VACC horses relative to CTRL horses. Horses challenged at Day 10 post vaccination experienced moderate or severe clinical signs of WNV infection in 3/3 CTRL compared to 5/6 VACC horses (P<0.05). CONCLUSIONS: This novel WN-FV chimera vaccine generates a protective immune response to WNV infection in horses that is demonstrated 10 days after a single vaccination and lasts for up to one year. POTENTIAL RELEVANCE: This is the first USDA licensed equine WNV vaccine to utilise a severe challenge model that produces the same WNV disease observed under field conditions to obtain a label claim for prevention of viraemia and aid in the prevention of WNV disease and encephalitis with a duration of immunity of 12 months.  相似文献   
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