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91.
92.
Ruis MA de Groot J te Brake JH Dinand Ekkel E van de Burgwal JA Erkens JH Engel B Buist WG Blokhuis HJ Koolhaas JM 《Applied animal behaviour science》2001,70(3):201-225
Endocrine, behavioural and immunologic processes, together with body growth, were evaluated in gilts that were defeated at 10 weeks of age in resident-intruder tests. Immediately after defeat, gilts were either separated from or reunited with a familiar conspecific (litter-mate; always a barrow). Gilts were assigned to one of four treatments: (a) DI: defeat, followed by isolation (separation from original litter-mate; n=8); (b) I: no defeat, isolation (control group; n=9); (c) DP; defeat, followed by pair-housing (reunion with original litter-mate; n=8); and (d) P: no defeat, pair-housing (control group; n=8). The following general conclusions were derived: (1) social defeat caused pronounced short-term elevations in hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal medullary activities, and of prolactin levels. Moreover, as soon as 1h after defeat, percentages of blood lymphocytes and neutrophilic granulocytes were, respectively, decreased and increased; (2) social defeat had some long-lasting influence on behaviour and physiology, but isolation predominantly determined responses in the longer term. Defeat, as well as isolation, resulted in increased cardiovascular activities compared to P controls, as observed in a novel object test (NOT: +7 days) and an aversion test (AVT: +14 days). Moreover, defeated as well as isolated gilts did not habituate to a repeated novel environment test (NET: -7, +2 and +7 days) in terms of frequencies of vocalising, whereas P controls did. Isolation, through the separation from any other pig, was responsible for the other observed long-term characteristics, which developed progressively. Isolated gilts showed high mobilities and high cortisol responses in the repeated NET (+7 days), not being habituated. This contrasted the reactions of pair-housed gilts, which were much reduced. In addition to their high cardiovascular activities in the NOT and the AVT, isolated gilts also displayed higher heart rates in the repeated NET and during human presence following the NOT, compared to pair-housed gilts. Finally, isolated gilts were more inhibited to approach a novel object (in the NOT) than pair-housed pigs; and (3) stress responses of defeated gilts were modulated by the subsequent social environment. Stimulation of the HPA-axis (plasma- and salivary cortisol) was prolonged in those defeated gilts which were isolated (observed in the first hour). Changes in leucocyte subsets were still observed after 3 days in DI, but were 'normalised' within 1 day in DP gilts. Two days after defeat, habituation to the repeated NET in terms of mobility and salivary cortisol responses occurred in control and DP gilts, but not in DI gilts. We argue that these effects of the social environment shortly after defeat were related to a stress-reducing effect of a stable social relationship, i.e. social support. 相似文献
93.
OBJECTIVE: To determine the usefulness of proliferating cell nuclear antigen (PCNA), p53 protein expression and transformed lymphocyte count (TLC) as adjunctive tests to differentiate indolent small B-cell lymphoma from large cell lymphoma in fine needle aspiration biopsies. STUDY DESIGN: Aspirates of lymphoproliferative disorders from April 1993 to January 1997 were reviewed. The percentage of TLCs was determined on the Papanicolaou smear. The percentage and intensity of p53 and PCNA immunocytochemical staining was evaluated on cell block sections. These results were compared and correlated with the final diagnoses based on available morphology, flow cytometry and clinical history. RESULTS: There were 40 cases of non-Hodgkin's lymphoma and 12 reactive lymph nodes. Adequate cell blocks were available on 16 large cell lymphomas, 7 grade 1-2 follicular center cell lymphomas, 6 mucosal associated lymphoid tissue lymphomas, 2 small lymphocytic lymphomas and 2 mantle cell lymphomas. Average TLC and p53 nuclear staining was highest in large cell lymphomas (57% TLC and 24% p53), followed by grades 1 and 2 follicular lymphomas (14% TLC and 15% p53) and lowest in other indolent lymphomas (< 10% TLC and < 1% p53). Average PCNA staining was highest in large cell lymphomas (46%) and lowest in small lymphocytic lymphomas (7%); however, TLC was the best parameter for differentiating large cell lymphoma from indolent small B-cell lymphoma. CONCLUSION: TLC differentiated large cell lymphoma from indolent small B-cell lymphoma better than either p53 or PCNA alone or in combination. Significant overlap between categories limits usefulness of these immunocytochemical stains for differentiating these entities. 相似文献
94.
A. C. Ramalhinho J. Marques JA Fonseca-Moutinho L. Breitenfeld 《Molecular biology reports》2013,40(8):5093-5103
Estrogen receptor alpha (ERα), that mediates the biologic effects of estrogen in estrogen-sensitive tissues like breast, is genetically polymorphic. To evaluate the association between ?397 PvuII (T>C) and ?351 XbaI (A>G) restriction fragment length polymorphisms (RFLPs) in intron 1 of ERα gene and susceptibility of breast cancer, we undertook a case–control study in BRCA1 185delAG and 5382insC/BRCA2 6174delT negative Portuguese women. The study population consisted of 107 patients with histological diagnosis of breast cancer and 121 women with no history of breast cancer. Genomic DNA was extracted from blood samples and genotyping analyses were performed by PCR–RFLP. XbaI polymorphism was associated with a significant reduced risk of breast cancer for carriers of the x allele in homozygozity (OR 0.178; 95 % CI 0.070–0.456; P < 0.001) or heterozigozity (OR 0.223; 95 % CI 0.089–0.561; P = 0.001). The PvuII polymorphism was associated with a non-significantly reduced risk. The combined analysis of PvuII and XbaI polymorphisms revealed none synergistic effect of the two genotypes, except for simultaneous carriers of pp and xx genotypes, that have a reduced risk of breast cancer (OR 0.226; 95 % CI 0.049–1.035; P = 0.044). The combination of PvuII and XbaI genotypes into haplotypes showed that carriers of two copies of the px (ppxx) haplotype had a reduced risk of breast cancer (OR 0.405; 95 % CI 0.194–0.843; P = 0.014), compared with PX (PPXX + PPXx + PpXX + PpXx) haplotypes. PvuII and XbaI polymorphisms were in linkage disequilibrium both in cases (D = 0.044, r2 = 0.049, X2 = 5.216, P = 0.022) and controls (D = 0.090, r2 = 0.139, X2 = 16.819, P < 0.001), but not in the entire sample population analyzed as a whole (D = 0.087, r2 = 0.0076, X2 = 1.733, P = 0.188). In conclusion, in this case–control study we found that ERα gene XbaI polymorphism may modify individual susceptibility for breast cancer in this population. 相似文献
95.
In search for an alternative for nutritional antimicrobials in piglet feeding, the effects of adding whole Cuphea seeds, as a natural source of medium chain fatty acids (MCFA), with known antimicrobial effects, and an exogenous lipase to a weaner diet were studied. The foregut flora, the gut morphology, some digestive parameters and the zootechnical performance of weaned piglets were investigated. Thirty newly weaned piglets, initial weight 7.0 ± 0.4 kg, were divided according to litter, sex and weight in two groups (control diet; Cuphea+lipase diet). The Cuphea seeds (lanceolata and ignea) (50 g kg?1) were substituted for soybean oil (15 g kg?1), Alphacell (25 g kg?1) and soy protein isolate (10 g kg?1) in the control diet. Also 500 mg kg?1 microbial lipase was added to the Cuphea diet. The piglets were weighted individually on days 0, 3, 7, 14 and 16. Feed intake was recorded per pen during days 0 to 3, 3 to 7, 7 to 14 and 14 to 16. On day 7 five piglets of each experimental group were euthanized for counting the gastric and small intestinal gut flora and for gut morphology at two sites of the small intestine (proximal, distal). The results indicate a trend towards improved performances parameters by feeding Cuphea + lipase. The enzymic released MCFA (1.7 g kg?1 fresh gastric contents) tended to decrease the number of Coliforms in the proximal small intestine, but increased the number in the stomach and distal small intestine. With Cuphea, the number of Streptococci was significantly lower in small intestine, but not in the stomach, while the number of Lactobacilli was significantly lower in the distal small intestine and tended to be lower in the stomach and proximal small intestine. No differences between the diets were noted for the total anaerobic microbial load in the stomach or in the gut. Feeding Cuphea+lipase resulted in a significantly greater villus height (distal small intestine) and a lesser crypt depth (proximal and distal small intestine) and greater villus/crypt ratio depth (proximal and distal small intestine). The intra-epithelial lymphocyte (IEL) counts per 100 enterocytes were significantly decreased in the proximal small intestine and tended to decrease in the distal small intestine by feeding the Cuphea+lipase diet. Both phenomena are indicative for a more healthy and better functional state of the mucosa. Present results are in line with foregoing research, showing that manipulation of the gut ecosystem by the enzymic in situ released MCFA in the stomach and foregut can result in improved performances of the piglets, which makes the concept a potential alternative for in-feed nutritional antibiotics. 相似文献
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97.
Gromadzka Grażyna Karpińska Agata Przybyłkowski Adam Litwin Tomasz Wierzchowska-Ciok Agata Dzieżyc Karolina Chabik Grzegorz Członkowska Anna 《Biometals》2014,27(1):207-215
Copper accumulation in tissues due to a biallelic pathogenic mutation of the gene: ATP7B results in a clinical phenotype known as Wilson disease (WD). Aberrations in copper homeostasis can create favourable conditions for superoxide-yielding redox cycling and oxidative tissue damage. Drugs used in WD treatment aim to remove accumulated copper and normalise the free copper concentration in the blood. In the current study the effect of decoppering treatment on copper metabolism and systemic antioxidant capacity parameters was analyzed. Treatment naïve WD patients (TNWD) (n = 33), those treated with anti-copper drugs (TWD) (n = 99), and healthy controls (n = 99) were studied. Both TNWD and TWD patients characterised with decreased copper metabolism parameters, as well as decreased total antioxidant potential (AOP), glutathione (GSH) level, activity of catalase, glutathione peroxidase (GPx), and S-transferase glutathione, compared to controls. TWD patients had significantly lower copper metabolism parameters, higher total AOP and higher levels of GSH than TWD individuals; however, no difference was observed between these two patient groups with respect to the rest of the antioxidant capacity parameters. Patients who had undergone treatment with d-penicillamine or zinc sulphate did not differ with respect to copper metabolism or antioxidant capacity parameters, with the exception of GPx that was lower in d-penicillamine treated individuals. These data suggest that anti-copper treatment affects copper metabolism as well as improves, but does not normalize, natural antioxidant capacity in patients with WD. We propose to undertake studies aimed to evaluate the usefulness of antioxidants as well as selenium as a supplemental therapy in WD. 相似文献
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99.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
100.