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51.
Yong-Bum Park Eun-Kyung Mo Jae-Young Lee Joo-Hee Kim Cheol-Hong Kim In-Gyu Hyun Jeong-Hee Choi 《Allergy, asthma & immunology research》2013,5(5):295-300
Purpose
As pet ownership increases, sensitization to animal allergens due to domestic exposure is a concern. Sensitization to animal allergens may occur from indirect exposure, as well as direct ownership of animals. However, there have been conflicting results regarding the association between pet ownership and sensitization to animal allergens in adults.Methods
In total, 401 patients with various allergic diseases were enrolled in this study. We performed skin prick tests with 55 common inhalant and food allergens, including dog, cat, and rabbit allergens. A mean wheal diameter of 3 mm or greater was considered a positive reaction. The exposure modality to each animal allergen was investigated using a questionnaire and included present ownership, past ownership, occupational exposure, occasional exposure, contact with pet owner, and no contact. Present ownership, past ownership, occupational, and occasional exposure were regarded as direct exposure.Results
The sensitization rate for animal allergens was 20.4% for dog, 15.0% for cat, and 9.0% for rabbit. Direct exposure to dogs (72.0%) was significantly higher than that of other animals (18.4% for cats and 16.7% for rabbits), whereas ''no contact'' with cats (78.3%) and rabbits (83.3%) was significantly higher than with dogs (26.8%; P<0.0001). Independent risk factors for sensitization to animal allergens were sensitization to Dermatophagoides pteronyssinus (OR=2.4, P=0.052), Dermatophagoides farinae (OR=5.1, P<0.001), cat (OR=4.4, P<0.0001), and direct exposure to dogs (OR=1.5, P=0.029) for dog, and sensitization to dog (OR=4.4, P<0.0001) and rabbit (OR=2.6, P=0.036) for cats. Finally, for rabbits, the independent risk factor was sensitization to Alternaria (OR=6.0, P<0.002).Conclusions
These results suggest that direct exposure to dogs contributes to the sensitization to dog allergens in patients with allergic diseases, whereas indirect exposure to cats and rabbits may induce sensitization to each animal''s allergen. 相似文献52.
《Journal of investigative surgery》2013,26(1):51-74
Implants placed in soft tissue evoke a foreign body reaction. Polymeric implants having smooth surfaces, such as silicone rubber implants, develop a nonadherent fibrogranulous tissue capsule which contracts over time and stiffens. Conventional porous implants, such as those made from textiles, usually have pores larger than 20 μm and they become infiltrated with inflammatory tissue. The in vivo cell reaction to polymeric surfaces having pores smaller than 10 μm has not been investigated systematically. In this study the histocompatibility of materials having mean pore diameters from 0.4 to 10 μm was assessed. A material available with several different defined pore sizes Versapor filter material) was tested in vivo to determine relation between pore size and qualitative tissue response. Silicone-coated samples were also tested to determine the dependence of the observed tissue response on the implant surface chemistry. Results showed nonadherent, contracting capsules around implants having pore diameters smaller than 0.5 μm. Implants with pores ranging from 1.4 to 1.9 μm evoked thin, tightly adherent fibrous capsules without inflammatory cells. Porosities of 3.3 μm and larger became infiltrated with inflammatory tissue. Results indicate that the obsexrved tissue response is predominantly dependent on implant surface topography and that variation in implant material may have little effect. It is concluded that a defined surface topography of 1 to 2 pm appears to allow direct fibroblast attachment to the surface independent of its chemical or electrochemical nature. Attached fibro-blasts then produce a minimal connective tissue response to the implant and prevent or diminish the presence of inflammatory cells at the implant/tissue interface. 相似文献
53.
目的研究全胃切除术后不同消化道重建术式对犬小肠动力的影响。方法将13只比格犬分为对照组(3只,仅行假手术),全胃切除后采用功能性间置空肠进行消化道重建(FJI组,7只)和全胃切除后采用Roux-en-Y吻合进行消化道重建(RY组,3只)。手术后48h处死比格犬。处死前1h灌人活性炭,检测小肠转运率。取吻合口上下5cm的小肠,分别应用苏木精一伊红染色、免疫组织化学染色和干涉显微镜观察和检测小肠炎性反应,小肠组织卡哈尔细胞(ICC)分布及上皮凋亡情况。结果对照组和FJI组的小肠转运率分别为0.14±0.03和0.32±0.11,显著低于RY组(0.52±0.21,P〈0.05)。FJI组较RY组的小肠分布更多的ICC;FJI组的小肠浆膜炎性反应(包括出血、纤维渗出、溃疡)、中性粒细胞和巨噬细胞浸润以及小肠上皮细胞凋亡情况均不如RY组明显。结论减少手术创伤、保持小肠连续性的功能性间置空肠吻合消化道重建方式,具有更好的食物储存功能,有利于术后小肠动力的恢复。 相似文献
54.
Nevins M Nevins ML Karimbux N Kim SW Schupbach P Kim DM 《Journal of periodontology》2012,83(5):565-573
Background: The objective of this study is to evaluate the potential for periodontal regeneration of a critical‐sized defect with the application of recombinant human platelet‐derived growth factor (rhPDGF‐BB) combined with either a particulate equine or a β‐tricalcium phosphate (β‐TCP) matrix. Methods: Critical‐sized intrabony 2‐wall defects were created bilaterally on the distal surface of the second premolar and the mesial surface of the first molar in nine hounds. Twelve defects received rhPDGF‐BB/equine treatment, 12 defects received rhPDGF‐BB/β‐TCP treatment, and the remaining 12 sites served as sham‐surgery controls. The animals were sacrificed after a 10‐week healing period. Results: Clinical healing was uneventful without obvious signs of overt gingival inflammation. Histologic and histomorphometric analyses revealed statistically that there were differences among the three groups in terms of new bone formation (P <0.001). The amount of test material for both rhPDGF‐BB/equine and rhPDGF‐BB/β‐TCP groups was comparable, but the amount of newly formed bone was significantly higher (P <0.01) in favor of the rhPDGF‐BB/equine group. The amount of new cementum formed for the rhPDGF‐BB/equine group (4.8 ± 1.3 mm) was significantly higher (P =0.001) than the sham‐surgery control group (1.7 ± 1.9 mm). Conclusion: Both rhPDGF‐BB/equine and rhPDGF‐BB/β‐TCP have the potential to support the regeneration of the periodontal attachment apparatus. 相似文献
55.
目的 利用基因芯片技术研究富氢水对γ射线照射后Beagle犬外周血淋巴细胞基因表达的影响.方法 将雄性Beagle犬随机分为对照组、单纯照射组和富氢水组(n=5),采用基因芯片技术对2.0 Gy60Coγ射线照射后6h各组Beagle犬外周血淋巴细胞的差异表达基因进行筛选,利用CGO (gene ontology)和KEGG(Kyoto encyclopedia of genes andgenomes)数据库对差异表达基因进行生物信息学分析,并应用实时荧光定量PCR技术对基因芯片结果进行验证.结果 单纯照射组筛选出差异表达2倍以上的基因4 730条,富氢水组筛选出差异表达2倍以上的基因4 493条,单纯照射组与富氢水组共同差异表达2倍以上的基因有1 606条;单纯照射组的差异表达基因对应的生物学过程、细胞组分及分子功能分别有10、9、3个功能簇,富氢水组差异表达基因对应的生物学过程、细胞组分及分子功能分别有15、3、4个功能簇.单纯照射组差异表达基因涉及19条生物学通路,富氢水组差异表达基因涉及24条生物学通路,单纯照射组与富氢水组的差异表达基因有5条共同生物学通路.选择2条差异表达基因进行mRNA水平的验证,PCR扩增结果与芯片结果具有良好的一致性.结论 富氢水对γ射线照射后Beagle犬外周血淋巴细胞基因表达的影响,可能涉及多种生物学过程、细胞组分、分子功能的改变及多条信号通路的激活. 相似文献
56.
前列腺素在紫外线上调纤溶活性中的作用 总被引:1,自引:0,他引:1
目的探讨前列腺素(PGs)在紫外线(UV)上调血纤溶活性中的作用。方法15只健康成年西北杂种犬被随机分成三组,UV组和UV+阿斯匹林组行全光谱UV20cm×20cm、447.72mJ/cm2照射胸腹部1次,其中UV+阿斯匹林组UV照射前在辐射区皮肤先进行直流电阿斯匹林离子导入1次;空白组既不照射UV也不行离子导入,作对照用。对比观察UV照射后48小时内辐射区皮肤抽吸水疱液中PGE2、PGD2、6oxoPGF1α浓度及血纤溶酶原激活物(PA)、纤溶酶原激活抑制物活性的动态变化。结果UV组在UV照后3小时PA活性明显增高,照后9小时达峰值;辐射区皮肤抽吸水疱液中三种PGs水平均在UV照后5小时明显升高,峰值约在UV照后5~9小时之间,三种PGs水平变化与PA活性变化均无显著相关性;UV+阿斯匹林组辐射区皮肤组织内三种PGs水平无明显升高,PA变化规律与UV组相类似,两组间PA活性无显著性差异(P>0.05)。结论PGE2、PGD2、6oxoPGF1α可能并不参与UV上调血纤溶活性作用 相似文献
57.
Roxanne Charles Asoke Basu Bryan Sanford Auria King‐Cenac Sharmine Melville‐Edwin Patricia Pow‐Brown Candice Sant Karla Georges 《Transboundary and Emerging Diseases》2020,67(Z2):129-134
Ticks and the pathogens they transmit can cause high morbidity and mortality in domestic animals. As part of a larger study to determine the tick‐borne pathogens infesting domestic animals and wildlife, the aim of this study was to survey the tick species infesting the canine and cattle populations in Trinidad, Tobago and St. Lucia. A total of 1,990 ticks were collected off 179 dogs in Trinidad (n = 163) and Tobago (n = 16) between June 2016 and 2018. Ticks were also collected from cattle throughout Trinidad (n = 1,098), Tobago (n = 306) and St. Lucia (n = 176). Collected ticks were morphologically identified using standard taxonomic keys. Tick‐infested dogs were characterized as pets (n = 161) or hunting dogs (n = 18). Only two tick species, Rhipicephalus sanguineus (1,926; 96.8%) and Amblyomma ovale (64; 3.2%), were found on the dogs. A total of 169 (94.4%) dogs and 10 (5.6%) dogs were infested with R. sanguineus and A. ovale, respectively. Three dogs (1.7%) were infested with both tick species. Hunting dogs or those closely associated with them were infested with A. ovale. Rhipicephalus sanguineus was widely distributed throughout both islands, whereas A. ovale was restricted to small foci in three rural settlements in both Trinidad (n = 2) and Tobago (n = 1). Rhipicephalus (Boophilus) microplus (n = 1,404) was the only tick species found in cattle from Trinidad (n = 62) and Tobago (n = 20), whilst R. B. microplus (n = 171) and Amblyomma variegatum (n = 5) were found infesting 14 and two heads of cattle, respectively, in St. Lucia. These preliminary findings will aid in determining whether there are links between ticks and tick‐borne pathogens associated with domestic, wildlife species and humans and give further insight into the potential movement of ticks and their pathogens between the human, animal and tropical forest interface. 相似文献
58.
目的观察携带人肝细胞生长因子基因的重组腺病毒(Ad—HGF)修饰的骨髓间充质干细胞(Msc)对犬后肢缺血后神经组织病理学的影响。方法18只犬随机分为Ad—HGF—MSC处理组、模型对照组和正常对照组,每组6只。将Ad—HGF—MSC处理组和模型对照组犬麻醉后,全结扎左后肢股动脉制作犬左后肢缺血模型,体外分离、培养犬骨髓MSC,转染Ad—HGF,并将含Ad-HGF—MSC的细胞悬液对Ad—HGF—MSC处理组犬病肢行多点肌肉注射,模型对照组犬注射等量的PBS缓冲液,正常对照组不进行任何处理。90d后,取组织标本,常规组织病理切片染色,光学显微镜下观察。结果12只犬均建模成功。模型对照组犬病侧股神经至肌束间的细小神经均发生显著退行性变,累及轴突、髓鞘和施旺细胞核。而Ad—HGF—MSC处理组犬的各级神经病变不明显,部分甚至与正常对照组无差别。结论Ad—HGF—MSC局部注射可减轻或阻遏犬后肢缺血后股神经组织损伤,具有一定的神经组织保护作用。 相似文献
59.
Nicolette Wright Deepak Subedi Saurav Pantha Krishna Prasad Acharya Louis Hendrik Nel 《Viruses》2021,13(2)
Despite being vaccine preventable, the global burden of dog rabies remains significant, and historically it is the rural and marginalized communities in developing countries of Africa and Asia that are most threatened by the disease. In recent years, the developing world has been experiencing unprecedented increases in urbanization, with a correspondingly massive increase in municipal solid waste generation, among other things. Inefficient and inadequate waste collection and management, due to lack of resources and planning, led to significant increases in the volumes of waste on the streets and in open dumps, where it serves as food sources for free-roaming dogs. In this commentary, we discuss examples of poor waste management and the likely impact on rabies control efforts through the sustenance of free-roaming dogs in some dog rabies-endemic countries. We aim to stress the importance of implementing strategies that effectively address this particular issue as an important component of humane dog population management, as it relates to aspirations for the control and elimination of dog rabies per se. 相似文献
60.
Long Pham-Thanh Thang Nguyen-Tien Ulf Magnusson Vuong Bui-Nghia Anh Bui-Ngoc Duy Le-Thanh ke Lundkvist Minh Can-Xuan Thuy Nguyen-Thi Thu Hau Vu-Thi Bich Hu Suk Lee Hung Nguyen-Viet Johanna Lindahl 《Viruses》2021,13(3)
Diseases caused by flaviviruses, including dengue fever and Japanese encephalitis, are major health problems in Vietnam. This cross-sectional study explored the feasibility of domestic dogs as sentinels to better understand risks of mosquito-borne diseases in Hanoi city. A total of 475 dogs serum samples from 221 households in six districts of Hanoi were analyzed by a competitive enzyme-linked immunosorbent assay (cELISA) for antibodies to the pr-E protein of West Nile virus and other flaviviruses due to cross-reactivity. The overall flavivirus seroprevalence in the dog population was 70.7% (95% CI = 66.4–74.8%). At the animal level, significant associations between seropositive dogs and district location, age, breed and keeping practice were determined. At the household level, the major risk factors were rural and peri-urban locations, presence of pigs, coil burning and households without mosquito-borne disease experience (p < 0.05). Mosquito control by using larvicides or electric traps could lower seropositivity, but other measures did not contribute to significant risk mitigation of flavivirus exposure in dogs. These results will support better control of mosquito-borne diseases in Hanoi, and they indicate that dogs can be used as sentinels for flavivirus exposure. 相似文献