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81.
If arteries penetrate bones through foramina, regional artery blood flow rates can be estimated from the foramen sizes. Femoral bone blood flow rates estimated from nutrient foramen sizes were previously not absolute, but only a relative blood flow index (Qi), because the size relationship between the foramen and the occupying artery was unknown. The current study used vascular contrast and micro-computerized tomographic scanning to investigate femoral nutrient foramen and nutrient artery sizes in three groups of sub-adult chickens (non-laying hens, laying hens, and roosters) of similar ages. The results indicate that the cross-sectional area of the nutrient artery lumen occupies approximately 20.2 ± 4.1% of the foramen for femora with only one foramen. Artery lumen size is significantly correlated with foramen size. Vascular contrast imaging is capable of estimating blood flow rates through nutrient arteries, as blood flow rates estimated from artery lumen casts are similar to blood flow rates measured by infusion of fluorescent-labeled microspheres. Laying hens tend to have higher nutrient artery perfusion rates than non-laying hens, probably due to extra oxygen and calcium requirements for eggshell production, although the calculated blood flow difference was not statistically significant. Histological embedding and sectioning along with vascular contrast imaging reveal variable nutrient foramen morphology and nutrient artery location among femora with more than one nutrient foramen.  相似文献   
82.
A lateral flow immunoassay (LFIA) and a competitive indirect ELISA (ciELISA) were developed and validated for the quantitative analysis of sulfaquinoxaline (SQX) in chicken tissues. The limits of quantification of ciELISA were 5 ng/ml for muscle samples and 12.5 ng/ml for liver samples; recoveries in tissues spiked with SQX at 25, 40 and 50 ng/g were 73.4–87.4% (n=5). With LFIA, no matrix effect was noticed during sample analyses. The optimisation of components allowed a detection limit of 0.5 ng/ml in tissues, which was 10–25 times lower than ciELISA. The recoveries in tissues fortified at levels 5, 10, 25 and 50 ng/g were 75.8–98% (n=5). Using HPLC as confirmatory method, 70 chicken muscle and liver samples from animal experiments were analysed by two immunoassays. The assay time for LFIA was only five min, whereas the analyses by ciELISA and HPLC took several hours. Comparison of ELISA, LFIA and HPLC data showed good correlations (r 2=0.99).  相似文献   
83.
Generally, there is an age-related decline in the human gut titer of Bifidobacterium species, but the titer in healthy centenarians was previously reported to be comparable to that found in much younger people. We addressed whether elevated Bifidobacterium titers relate positively to immune function. This study evaluated the immunoactivities of 2 Bifidobacterium strains (B adolescentis BBMN23 and B longum BBMN68) isolated from healthy centenarians in China. Different dosages (2 × 1011, 2 × 109, or 2 × 107 colony-forming units [CFU]/kg body weight) of live bifidobacteria were orally administered once per day to healthy BALB/c mice, and the control group was given sterile skim milk every day. After 4 weeks, the immune parameters including cellular immunity (delayed-type hypersensitivity [DTH], and splenic lymphocyte proliferation), humoral immunity (serum hemolytic activity in immunized animals), and nonspecific immunity (peritoneal macrophages phagocytsis natural killer [NK] cell activity) were measured. We report that both Bifidobacterium strains independently increased the DTH response. Macrophage phagocytosis was also enhanced, while activities of the NK cells and levels of the serum hemolysin also were significantly higher than in the control group. There was a significant increase in splenic lymphocyte proliferation in bifidobacteria treatment animals compared to controls. In conclusion, ingestion of B. adolescentis BBMN23 and B. longum BBMN68 can enhance both innate and acquired immunity in healthy specific pathogen-free (SPF) mice and strains of bifidobacteria from healthy centenarians in Bama longevity villages in China may possess potentially valuable immunomodulatory properties.  相似文献   
84.
An infecting strain VLA2/18 of Campylobacter jejuni was obtained from an individual with campylobacteriosis and used to prepare chicken sera by experimental infection to investigate the role of serum anti-ganglioside antibodies in Guillain-Barré syndrome. Both sera of the patient and chicken contained anti-ganglioside antibodies and anti-Lipid A (anti-Kdo2-Lipid A) antibodies directed against the lipid A portion of the bacterial lipooligosaccharide. The anti-Kdo2-Lipid A activities inhibited voltage-gated Na (Nav) channel of NSC-34 cells in culture. We hypothesized that anti-Kdo2-Lipid A antibody acts on the functional inhibition of Nav1.4. To test this possibility, a rabbit peptide antibody (anti-Nav1.4 pAb) against a 19-mer peptide (KELKDNHILNHVGLTDGPR) on the alpha subunit of Nav1.4 was produced. Anti-Nav1.4 pAb was cross-reactive to Kdo2-Lipid A. Anti-Kdo2-lipid A antibody activity in the chicken serum was tested for the Na(+) current inhibition in NSC-34 cells in combination with mu-Conotoxin and tetrodotoxin. Contrary to our expectations, the anti-Kdo2-Lipid A antibody activity was extended to Nav channels other than Nav1.4. By overlapping structural analysis, it was found that there might be multiple peptide epitopes containing certain dipeptides showing a structural similarity with v-Lipid A. Thus, our study suggests the possibility that there are multiple epitopic peptides on the extracellular domains of Nav1.1 to 1.9, and some of them may represent target sites for anti-Kdo2-Lipid A antibody, to induce neurophysiological changes in GBS by disrupting the normal function of the Nav channels.  相似文献   
85.
Our previous studies suggested that a direct hippocampo‐cerebellar projection might exist in the chicken. To confirm such a presumption of hippocampo‐cerebellar interactions, horseradish peroxidase (HRP) was used as a retrograde tracer to be injected into the white matter of the folia VI–VIII of the cerebellum in young and adult chickens. In another set of experiments, young chickens were subjected to electrolytic lesions of the hippocampal formation (HF), especially the ventromedial portion, and the cerebellum was observed with the electron microscope to find neuronal degeneration in the HF. Following injections of HRP into the cerebellum, a large number of labeled neurons were found in the area APHm‐APHim of the HF in the young and adult chickens. As a result of the electrolytic lesions of the APHm‐APHim in the HF, many large degenerated nerve fibers were found in the white matter in the vicinity of the lateral nucleus of the cerebellum, and some small degenerated fibers were found in the white matter of the folia VI–VIII. In the cerebellar cortex of folia VI–VIII, degenerated axonal terminals occurred in both the molecular and Purkinje layers, but not in the granular layer. In the lateral nucleus, some dark degenerating axonal terminals were recognized to connect with the perikarya of neurons of this nucleus. The present experiments demonstrate that the APHm‐APHim of the HF directly projected to the cortex of folia VI–VIII and the lateral nucleus of the cerebellum in young chickens. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
86.
In the domestic chicken, providing visual barriers for a brief period early in life has been found to improve spatial memory [R. Freire et al. (2004)Animal Behaviour, 67, 141-150]. In the present study we compared the structure of neurons in the hippocampus and neostriatum in chicks reared with or without visual barriers. From 8 to 16 days of age, chicks were reared in pens either with two wooden screens (Treatment E) or with no screens (Treatment C). At 16 days of age, chicks were anaesthetized, perfused intracardially and brain samples collected and stained using a Golgi-Cox technique. Morphometric analysis revealed that the multipolar projection neurons of Treatment E chicks had longer dendrites (ANOVA, F(1,14) = 7.4, P < 0.05) and had more spines per 20 micro m of dendrite (SLD; ANOVA, F(1,14) = 10.6, P < 0.01) than those of Treatment C chicks. By contrast, no evidence was found that rearing treatment differentially influences dendrite length or SLD in the neostriatum, suggesting that the above environment-induced changes may be specific to the hippocampus. Multipolar projection neuron dendrites of the right hemisphere were longer (ANOVA, F(1,14) = 36.4, P < 0.0001) and had more spines (ANOVA, F(1,14) = 8.8, P < 0.05) than dendrites of the left hemisphere, supporting previous findings that the right hemisphere of chickens is predominantly involved in spatial processing. We conclude that the chicken provides a useful model for the study of developmental plasticity in brain and behaviour, partly because the possibility of rearing chicks in isolation and imprinting them on an artificial object provides a means of accurately manipulating early experience.  相似文献   
87.
Brain spectrin, a membrane-related cytoskeletal protein, exists as two isoforms. Brain spectrin 240/235 is localized preferentially in the perikaryon and axon of neuronal cells and brain spectrin 240/235E is found essentially in the neuronal soma and dendrites and in glia (Riederer et al., 1986, J. Cell Biol., 102, 2088 - 2097). The sensory neurons in dorsal root ganglia, devoid of any dendrites, make a good tool to investigate such differential expression of spectrin isoforms. In this study expression and localization of both brain spectrin isoforms were analysed during early chicken dorsal root ganglia development in vivo and in culture. Both isoforms appeared at embryonic day 6. Brain spectrin 240/235 exhibited a transient increase during embryonic development and was first expressed in ventrolateral neurons. In ganglion cells in situ and in culture this spectrin type showed a somato - axonal distribution pattern. In contrast, brain spectrin 240/235E slightly increased between E6 and E15 and remained practically unchanged. It was localized mainly in smaller neurons of the mediodorsal area as punctate staining in the cytoplasm, was restricted exclusively to the ganglion cell perikarya and was absent from axons both in situ and in culture. This study suggests that brain spectrin 240/235 may contribute towards outgrowth, elongation and maintenance of axonal processes and that brain spectrin 240/235E seems to be exclusively involved in the stabilization of the cytoarchitecture of cell bodies in a selected population of ganglion cells.  相似文献   
88.
Summary The effect of vitamin A deficiency was studied in chickens infected with 500 Ascaridia galli eggs and controls. Diet 1 (deficient, 500 IU vitamin A or 172 μg retinol acetate per kg diet), Diet 2 (deficient, 1000 IU vitamin A or 344 μg retinol acetate per kg diet) and Diet 3 (sufficient, 1500 IU vitamin A or 516 μg retinol acetate per kg diet) were assigned to 46 chickens each. Clinical signs, weight gains, livers’ weights, vitamin A levels, worm burdens and parasite eggs’ excretions were recorded. Infected chickens had lower weight gains than the controls fed alike. Chickens given Diet 1 stored lesser vitamin A in liver than those fed Diet 3. Although worm counts in the 3 groups did not differ significantly, chickens fed Diet 1 excreted more A. galli eggs than those fed the 2 other diets. Female worms harboured by chickens fed Diet 1 had higher fecundity at week 5 pi than those of chickens fed Diet 2. Results indicated that Vitamin A is important for poultry in the moderation of the infection with A. galli.  相似文献   
89.
目的对禽流感病毒H5、H7亚型进行更快速、更灵敏检测。方法根据禽流感病毒(AIV)核蛋白基因和血凝素基因设计3对特异性引物,建立在结合红细胞富集AIV病毒的基础上进行多重RT-PCR检测方法。结果该方法在1个反应体系中不仅能够鉴定A型流感病毒,而且可以同时确定是否为H5和H7亚型AIV;该方法的检测下限可达2.5pg的病毒RNA;对于参考毒株都可以扩增出预期大小的基因片段,而对新城疫病毒和传染性支气管炎病毒的平行对照结果均呈阴性。结合AIV能够吸附鸡红细胞并在一定条件下解离的特点,利用鸡红细胞对48份已确诊样品进行病毒富集,然后用建立的多重RT-PCR方法检测富集产物结果显示48个样品中,30个为H5亚型AIV阳性,与病毒分离结果完全一致。结论由以上结果初步表明本研究建立的检测方法快速,特异,在禽流感临床筛检中显示出良好的应用前景。  相似文献   
90.
Respiratory infection is the major cause of morbidity and mortality in cystic fibrosis (CF) patients. Chronic Pseudomonas aeruginosa (PA) infections ultimately occur in virtually all patients. It is impossible to eradicate PA when a patient has been chronically colonized. Immunotherapy with specific egg‐yolk antibodies (IgY) may be an alternative to antibiotics for the prevention of PA infections. We wanted to determine if treatment with specific IgY can prolong the period between the first and the second PA colonization? And long‐term, can the treatment diminish the number of positive PA cultures and postpone the onset of chronic colonization? CF patients gargled daily with an IgY‐antibody preparation, purified from eggs of hens immunized with PA bacteria. They were compared to a group of patients who did not gargle with the preparation. Both groups had their first colonization with PA eradicated by antibiotics. The basic treatment was essentially the same in both groups. In the initial study, the period between the first and second colonization with PA was significantly prolonged for the treated vs. the control group (Kaplan‐Meier P = 0.015, Breslow test). In the prolonged study, the treated group had only 2.5 sputum cultures positive for PA per 100 months of observation, and none of these patients became chronically colonized with PA. No adverse events were reported. In the control group, 13.7 cultures per 100 months of observation were positive for PA, and 5 (24%) patients became chronically colonized with PA. This feasibility study shows that antipseudomonal IgY has the potential to effectively prevent PA colonization without any severe adverse effects. A phase III study should be initiated. Pediatr Pulmonol. 2003; 35:433–440. © 2003 Wiley‐Liss, Inc.  相似文献   
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