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1.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases. 相似文献
2.
Ariel Paracampo Marina Solis Carlos Bonetto 《International journal of environmental health research》2015,25(1):96-103
Chlorpyrifos is the most used insecticide in Argentina. Cnesterodon decemmaculatus is a widely distributed, endemic fish from Neotropical America. It attains high densities in the shallow water assemblages of Argentina and Brazil. The aim of this study was to assess the acute toxicity of chlorpyrifos to C. decemmaculatus. The mean 96-h LC50 of three independent determinations was 105.3 (±?3.1) μg/L. Sublethal effects were observed. Swimming behavioral changes at each chlorpyrifos exposure concentration were reported. C. decemmaculatus represents a good model for ecotoxicological risk assessment. 相似文献
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Soosai Manickam Amirtham Ozlem Ozbey Upasana Kachroo Boopalan Ramasamy Elizabeth Vinod 《Clinical anatomy (New York, N.Y.)》2020,33(3):343-349
Bone containing tissues such as osteochondral joint are resistant to routine tissue processing, therefore require decalcification. This technique causes removal of mineral salts, but in the process may macerate the organic tissue, hence the need for tissue fixation. Such severe processing demands careful antigen retrieval to necessitate optimal staining. The aim of our study was to compare five different antigen retrieval protocols (heat retrieval and protein digestion) following decalcification of rabbit knee joints using two different techniques (20% formic acid and 10% ethylenediamine-tetra acetic acid: EDTA). Osteochondral sections were compared based on time required for decalcification, ease of sectioning, morphological integrity using HE staining and antigen preservation (Collagen type II) using immunohistochemistry. The two decalcification solutions did not impair the tissue morphology and ease of sectioning. Joints processed with formic acid decalcified four times faster than EDTA. Among the five antigen retrieval approaches, maximal collagen II uptake with minimal nonspecific staining was found with protein digestion (pronase and hyaluronidase) in both formic acid and EDTA sections. For osteo-chondral sections, we recommend using 10% EDTA for decalcification and pronase plus hyaluronidase for antigen retrieval if maintaining tissue morphology is crucial, whereas if time is of the essence, 20% FA with pronase plus hyaluronidase is the faster option while still preserving structural integrity. Clin. Anat. 33:343–349, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
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桑根酮C对博莱霉素诱导小鼠肺纤维化改善作用及机制研究 总被引:1,自引:0,他引:1
目的观察桑根酮C对博莱霉素诱导的小鼠肺纤维化的影响,并探讨其可能的作用机制。方法 C57BL/6小鼠随机分为4组,即假手术组、模型组和桑根酮C(100、50 mg/kg)组,每组20只。假手术组小鼠气管内注射生理盐水,模型组小鼠气管内注射博莱霉素诱导肺纤维化模型。术后第4天开始给药,连续给药28d后检测小鼠呼吸功能;检测肺内羟脯氨酸含量;HE染色观察肺内炎症表现;Masson染色观察肺内胶原活性;免疫组化法检测肺内转化生长因子-β1(TGF-β1)蛋白表达量;免疫蛋白印迹法检测肺内α平滑肌肌动蛋白(α-SMA)、核转录因子-κB p65(NF-κB p65)、磷酸化的核转录因子-κB p65(p-NF-κB p65)、Ⅰ型胶原和Ⅲ型胶原表达量。结果与模型组比较,桑根酮C能够改善经博莱霉素诱导形成肺纤维化后小鼠的呼吸功能,能够明显降低肺内羟脯氨酸含量,明显减轻肺内炎症和胶原沉积,肺内TGF-β1、α-SMA、NF-κBp65、p-NF-κBp65、Ⅰ型胶原和Ⅲ型胶原蛋白表达量明显降低。结论桑根酮C能够明显改善博莱霉素诱导小鼠肺纤维化,改善呼吸功能,其机制可能与抑制TGF-β1过表达和降低炎症转录因子NF-κB及磷酸化表达有关。 相似文献
8.
Reem Haj-Ali BDS DDS MS ; Mary Walker DDS PhD ; Karen Williams PhD ; Yong Wang PhD ; Paulette Spencer DDS PhD 《Journal of prosthodontics》2006,15(2):82-88
PURPOSE: The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin. MATERIALS AND METHODS: Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively. RESULTS: The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm. CONCLUSIONS: The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure. 相似文献
9.
Kenichi Okubo Masashi Kobayashi Hiromasa Morikawa Eiichi Hayatsu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(7):268-272
Objective: Induction chemoradiotherapy followed by anatomical resection is a current therapeutic strategy for non-small-cell lung cancer
with mediastinal node involvement. Dense peritracheal fibrosis and sclerosis after chemoradiotherapy cause difficult mediastinal
node dissection. We evaluated a novel technique to make the mediastinal node dissection easier after induction therapy. Methods: At the end of mediastinoscopic node biopsy for staging of lung cancer, cotton-type collagen was inserted anterior and lateral
to the trachea in patients with pathologically confirmed mediastinal node involve-ment (n=45). The induction therapy consisted
of concurrent use of platinum-based chemotherapy and hyperfractionated radiotherapy. After the chemoradiotherapy all patients
underwent a pulmonary resection with complete mediastinal node dissection 7–12 weeks after the collagen insertion. Surgical
findings of the mediastinum and the time for node dissection were compared with those without collagen insertion at mediastinoscopy
after chemoradiotherapy (n=5). Results: All five patients without collagen insertion showed sclerotic and fibrotic change of mediastinal nodes with severe adhesion
to the trachea. In 42 of 45 patients with collagen insertion (93.3%) the collagen remained unabsorbed and separated the mediastinal
nodes from the trachea. Mediastinal node dissection was easily accomplished by removing mediastinal tissues lateral and anterior
to the collagen. The rate of mediastinal node separation was significantly higher with collagen insertion than without (p<
0.0001). The times for node dissection in patients with and without collagen insertion showed no significant difference. Conclusion: Cotton-type collagen insertion at staging mediastinoscopy for lung cancer separates the mediastinal nodes from the trachea
and makes the node dissection easier after induction chemoradiotherapy. 相似文献
10.
研究了预脱水鱼片含水量、微波功率、真空度对真空微波加工香脆鳙鱼片品质的影响,在此基础上,采用混合正交试验进一步优化了真空微波制备香脆鳙鱼片的工艺条件。研究结果表明,适宜的水分含量和微波功率可以提高鱼片的膨化率和脆度,改善鱼片的感官品质。高真空度可以改善鱼片的膨化作用和脆性,提高微波加热的效率,很大程度上避免了鱼片出现焦黑点。最佳的真空微波加热条件是预脱水鱼片水分质量分数控制在(15.3±1)%(50℃鼓风干燥3.5 h),微波功率设定为高火档(686±3.5)W,在真空度0.095 MPa下加热12 s后,间歇摇匀后再加热10 s。 相似文献