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1.
This study was conducted to examine the psycho-emotional effects of repeated oral exposure to capsaicin, the principal active component of chili peppers. Each rat received 1 mL of 0.02% capsaicin into its oral cavity daily, and was subjected to behavioural tests following 10 daily administrations of capsaicin. Stereotypy counts and rostral grooming were significantly increased, and caudal grooming decreased, in capsaicin-treated rats during the ambulatory activity test. In elevated plus maze test, not only the time spent in open arms but also the percent arm entry into open arms was reduced in capsaicin-treated rats compared with control rats. In forced swim test, although swimming duration was decreased, struggling increased in the capsaicin group, immobility duration did not differ between the groups. Repeated oral capsaicin did not affect the basal levels of plasma corticosterone; however, the stress-induced elevation of plasma corticosterone was prolonged in capsaicin treated rats. Oral capsaicin exposure significantly increased c-Fos expression not only in the nucleus tractus of solitarius but also in the paraventricular nucleus. Results suggest that repeated oral exposure to capsaicin increases anxiety-like behaviours in rats, and dysfunction of the hypothalamic-pituitary-adrenal axis may play a role in its pathophysiology.  相似文献   
2.

Background:

Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).

Methods:

In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.

Results:

Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.

Conclusions:

Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation.  相似文献   
3.
ObjectiveTo investigate the association between migraine and ischaemic or haemorrhagic stroke in young women.DesignHospital based case-control study.SettingFive European centres participating in the World Health Organisation Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception.Subjects291 women aged 20-44 years with ischaemic, haemorrhagic, or unclassified arterial stroke compared with 736 age and hospital matched controls.InterventionQuestionnaire.ResultsAdjusted odds ratios associated with a personal history of migraine were 1.78 (95% confidence intervals, 1.14 to 2.77), 3.54 (1.30 to 9.61), and 1.10 (0.63 to 1.94) for all stroke, ischaemic stroke, and haemorrhagic stroke respectively. Odds ratios for ischaemic stroke were similar for classical migraine (with aura) (3.81, 1.26 to 11.5) and simple migraine (without aura) (2.97, 0.66 to 13.5). A family history of migraine, irrespective of personal history, was also associated with increased odds ratios, not only for ischaemic stroke but also haemorrhagic stroke. In migrainous women, coexistent use of oral contraceptives or a history of high blood pressure or smoking had greater than multiplicative effects on the odds ratios for ischaemic stroke associated with migraine alone. Change in the frequency or type of migraine on using oral contraceptives did not predict subsequent stroke. Between 20% and 40% of strokes in women with migraine seemed to develop directly from a migraine attack.ConclusionsMigraine in women of childbearing age significantly increases the risk of ischaemic but not haemorrhagic stroke. The coexistence of oral contraceptive use, high blood pressure, or smoking seems to exert a greater than multiplicative effect on the risk of ischaemic stroke associated with migraine.

Key messages

  • A personal history of migraine was associated with increased risk of ischaemic but not haemorrhagic stroke
  • Coexistence of risk factors—use of oral contraceptives, high blood pressure, or smoking had more than multiplicative effects on odds ratios for ischaemic stroke associated with migraine alone
  • A family history of migraine, irrespective of a personal migraine history, was associated with increased risk of ischaemic and haemorrhagic stroke
  • Up to 40% of strokes in migrainous women develop directly out of a migraine attack—so called migrainous strokes
  • A change in type or frequency of migraine with use of oral contraceptives did not predict subsequent stroke
  相似文献   
4.

Background  

The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats.  相似文献   
5.
The geographic patterns of transmission opportunities of vector‐borne zoonoses are determined by a complex interplay between the migration patterns of the host and the vector. Here we examine the impact of host migration on the spread of a tick‐borne zoonotic disease, using Lyme Borreliosis (LB) spirochaetal species in Europe. We demonstrate that the migration of the LB species is dependent on and limited by the migration of their respective hosts. We note that populations of Borrelia spp. associated with birds (Borrelia garinii and B. valaisiana) show limited geographic structuring between countries compared with those associated with small mammals (Borrelia afzelii), and we argue that this can be explained by higher rates of migration in avian hosts. We also show the presence of B. afzelii strains in England and, through the use of the multi‐locus sequence analysis scheme, reveal that the strains are highly structured. This pattern in English sites is very different from that observed at the continental sites, and we propose that these may be recent introductions.  相似文献   
6.
NK cells infiltrate human herpetic lesions, but their role has been underexplored. HSV can stimulate innate immune responses via surface TLR2, which is expressed on monocyte-derived dendritic cells (DCs) and NK cells. In this study, UV-inactivated HSV1/2 and immunodominant HSV2 glycoprotein D peptides conjugated to the TLR2 agonist dipalmitoyl-S-glyceryl cysteine stimulated CD4 T lymphocyte IFN-γ responses within PBMCs or in coculture with monocyte-derived DCs. NK cells contributed markedly to the PBMC responses. Furthermore, NK cells alone were activated directly by both Ags, also upregulating HLA-DR and HLA-DQ and then they activated autologous CD4 T lymphocytes. Using Transwells, Ag-stimulated NK cells and CD4 T lymphocytes were shown to interact through both cell-to-cell contact and cytokines, differing in relative importance in different donors. A distinct immunological synapse between Ag-stimulated NK cells and CD4 T lymphocytes was observed, indicating the significance of their cell-to-cell contact. A large proportion (57%) of NK cells was also in contact with CD4 T lymphocytes in the dermal infiltrate of human recurrent herpetic lesions. Thus, NK cells stimulated by TLR2-activating HSV Ags can present Ag alone or augment the role of DCs in vitro and perhaps in herpetic lesions or draining lymph nodes. In addition to DCs, NK cells should be considered as targets for adjuvants during HSV vaccine development.  相似文献   
7.

Background  

Several forms of progressive retinal atrophy (PRA) segregate in more than 100 breeds of dog with each PRA segregating in one or a few breeds. This breed specificity may be accounted for by founder effects and genetic drift, which have reduced the genetic heterogeneity of each breed, thereby facilitating the identification of causal mutations. We report here a new form of PRA segregating in the Border Collie breed. The clinical signs, including the loss of night vision and a progressive loss of day vision, resulting in complete blindness, occur at the age of three to four years and may be detected earlier through systematic ocular fundus examination and electroretinography (ERG).  相似文献   
8.
The genetic diversity of Borrelia burgdorferi sensu lato was assessed in individual adult Ixodes ricinus ticks from Europe by direct PCR amplification of spirochetal DNA followed by genospecies-specific hybridization. Analysis of mixed infections in the ticks showed that B. garinii and B. valaisiana segregate from B. afzelii. This and previous findings suggest that host complement interacts with spirochetes in the tick, thereby playing an important role in the ecology of Lyme borreliosis.  相似文献   
9.
三氧化二砷对食管癌细胞增殖和热休克蛋白70表达的影响   总被引:2,自引:0,他引:2  
目的:研究三氧化二砷(As2O3)对食管癌细胞增殖和热休克蛋白70(HSP70)表达的影响。方法:通过相差显微镜、流式细胞术、免疫细胞化学染色和免疫印迹分析等方法观察As2O3对人食管癌细胞株EC1的作用效果和作用机制。结果:与对照组相比,经2μmol/L和5μmol/Las2O3作用的细胞出现明显的生长抑制,G2/M期细胞比例增加;2μmol/Las2O3作用48h后经Ecl细胞HSP70(heat shock protein70)及HSC70(heat shock cognate protein70)表达均增加。结论:As2O3诱导食管癌细胞G2/M期阻滞抑制细胞增殖和生长;HSP70的升高是细胞对As2O3作用后出现的应激反应,并与细胞周期阻滞相关。  相似文献   
10.

Purpose

Dairying is a relatively intensive livestock production system and contributes to a range of environmental impacts. In the southern hemisphere, dairy farming systems are based mainly on outdoor grazing of permanent pastures. The objectives of this study were to (i) assess environmental profiles and (ii) to identify environmental hotspots in a pasture-based dairy farming system.

Methods

A cradle-to-farm gate life cycle assessment of 53 dairy farms in the Waikato region, New Zealand, was carried out, using 1 kg of fat- and protein-corrected milk as the functional unit. Twelve environmental impact categories were assessed: climate change (CC), ozone depletion potential (ODP), cancer effects (Cancer), non-cancer effects (non-cancer), particulate matter (PM), ionizing radiation (IR), photochemical ozone formation potential (POFP), acidification potential (AP), terrestrial eutrophication potential (TEP), freshwater eutrophication potential (FEP), marine eutrophication potential (MEP) and ecotoxicity for aquatic freshwater (Ecotox). Contribution and sensitivity analyses were performed to determine key hotspots and investigate potential changes in results due to methodological choices.

Results and discussion

The on-farm stage contributed >50 % of the total result for 7 out of 12 indicators (CC, Non-cancer, PM, POFP, AP, TEP, MEP). The off-farm rearing of replacement animals contributed 11–20 % to the total result for all indicators. The production of brought-in (from off-farm) feeds for use on the dairy farms contributed >10 % to the indicator results for Non-cancer (25 %), FEP (15 %), MEP (12 %) and Ecotox (19 %). The manufacturing of agrichemicals for use on the dairy farms contributed >10 % to the indicator results for ODP (26 %), Cancer (26 %), PM (19 %), IR (46 %), FEP (25 %) and Ecotox (42 %). The transportation of off-farm inputs for use on the dairy farms contributed >10 % to the impacts on ODP (15 %), IR (21 %) and POFP (11 %). Sensitivity analysis demonstrated the influence of choices associated with data sources, inventories and impact assessment models on the results.

Conclusions

The off-farm activities together contributed >50 % to 5 out of 12 impact indicator results, >45 % to a further two impact indicator results and 32 % of the CC result. Therefore, environmental improvement options should focus on both on-farm and off-farm activities. A focus on just one impact category (such as CC) risks ignoring the environmental hotspots that are revealed in a more comprehensive environmental assessment.
  相似文献   
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