血小板源生长因子对人血管成纤维细胞DNA及胶原蛋白合成的影响

目的:观察血小板源生长因子对培养的人血管成纤维细胞DNA及胶原蛋白合成的影响。方法:采用培养的人血管成纤维细胞,应用 [³H]-TdR和 [³H]-脯氨酸掺入的方法,观察血小板源生长因子-BB对人血管成纤维细胞DNA合成以及胶原蛋白合成的影响。结果:血小板源生长因子-BB可促进静止状态的人血管成纤维细胞DNA及胶原蛋白的合成,在 30μg/L浓度时DNA及胶原蛋白的合成达到高峰,DNA及胶原蛋白分别于 2 4h和 36h合成最为显著。结论:血小板源生长因子-BB可明显促进培养的人血管成纤维细胞DNA及胶原蛋白的合成     

肺癌细胞外基质的表达与临床病理的关系

目的探讨原发性肺癌层粘蛋白（Ｌａｍｉｎｉｎ,ＬＮ）、纤维连接蛋白（ｆｉｂｒｏｎｅｃｔｉｎ,ＦＮ）和Ⅳ型胶原的表达与临床病理的关系。方法采用免疫组化ＬＳＡＢ法检测１８４例肺癌标本中ＬＮ、ＦＮ和Ⅳ型胶原的表达。结果ＬＮ及Ⅳ型胶原在中、高分化的肺鳞癌中的表达均明显强于低分化组（Ｐ＜００１）,在有无淋巴结转移两组间的表达差异均具显著性（Ｐ＜００５）;肺鳞癌５年以上生存组ＬＮ、Ⅳ型胶原的表达明显高于０５年内死亡组（Ｐ＜００１）,ＦＮ的表达亦有差异（Ｐ＜００５）。肺腺癌的５年以上生存组中ＦＮ、Ⅳ型胶原的表达均强于０５年内死亡组（Ｐ＜００５,００１）。结论ＬＮ和Ⅳ型胶原的表达与肺鳞癌的组织学分级和淋巴结转移有关;ＬＮ、ＦＮ、Ⅳ型胶原的表达均可作为评估肺鳞癌预后的指标,而腺癌的预后仅与ＦＮ、Ⅳ型胶原的表达有关。     

Prestress Due to Dimensional Changes Caused by Demineralization: A Potential Mechanism for Microcracking in Bone

Microcracking in bone due to internal strains caused by mineralization is a possible mechanism of damage. Similar damage can be seen in other biological composites such as trees experiencing growth-related prestresses. Dimensional changes in cortical bone due to demineralization and experimental glycation were studied to test whether mineralization-related prestrains are consistent with observed microcracking patterns in bone. A microscopy technique that enables wet measurements of length and angle of milled bone specimens was used. Demineralization of bovine and human bones caused significant anisotropic changes in tissue size. Dimensional changes due to demineralization in bovine bone were prevented or reduced when collagen cross linking was increased by glycation. The dimensional changes of bone caused by demineralization are consistent with the hypothesis that mineralization-caused stresses in remodeling tissue can cause microcracks. © 2002 Biomedical Engineering Society. PAC2002: 8719Rr     

Acceleration of bone formation with BMP2 in frame-reinforced carbonate apatite–collagen sponge scaffolds

The development is expected of scaffold biomaterials that feature a shape-maintaining property in addition to high porosity and large pores that cells can easily invade. To develop a new biodegradable scaffold biomaterial reinforced with a frame, synthesized carbonate apatite (CO₃Ap) was mixed with neutralized collagen gel, and the CO₃Ap–collagen mixtures were lyophilized into sponges in a porous hydroxyapatite (HAp) frame ring. X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR) analyses together with chemical analysis indicated that the synthesized CO₃Ap had a crystalline nature and a chemical composition similar to that of bone. Scanning electron microscope (SEM) observation showed that the CO₃Ap–collagen sponge had a sui pore size for cell invasion. In proliferation and differentiation experiments with osteoblasts, alkaline phosphatase and osteopontin activity were clearly detected. When these sponge–frame complexes with bone morphogenic protein (rh-BMP2) were implanted beneath the periosteum cranii of rats, significant new bone was created at the surface of the periosteum cranii after 4 weeks of implantation. These reinforced CO₃Ap–collagen sponges with rh-BMP2 are expected to be used as hard tissue scaffold biomaterials for the therapeutic purpose of the rapid cure of bone defects.     

Autologous rib perichondrial grafts in experimentally induced osteochondral lesions in the sheep-knee joint: Morphological results

Summary The purpose of the present study was to examine the fate of autologous perichondrial grafts after transplantation into cartilage lesions in weight-bearing joints. Osteochondral lesions were made in the articular surface of knee joints in 36 sheep. The defects were filled with autologous rib perichondrial grafts which were secured by either collagen sponges (12 animals) or fibrin glue (12 animals). Defects without perichondrial grafts served as controls (12 animals). Following 1 week of immobilization of the operated leg, the plaster was removed and the animals were allowed to move freely. Animals were sacrificed after 4, 8, 12 and 16 weeks. The grafts were removed and investigated histologically. In contrast to weight-bearing areas and control defects, hyaline-like cartilage formation was seen in non-weightbearing areas after 4 weeks. This newly formed cartilage revealed strong metachromasia following staining with acidic toluidine blue and reacted positively with periodic acid-Schiff, indicating de novo synthesis of proteoglycans and glycoproteins. Scanning electron microscopy and examinations with polarized light confirmed a hyaline cartilage-like architecture for the surface area as well as for the fibre orientation of the whole graft. Enzyme histochemistry for alkaline and acid phosphatase activity showed positive reactivity only at the base of the transplants.     

FD-1冷冻干燥机的研制及生物材料的冷冻干燥

观察自制冷冻干燥机冷冻干燥生物材料的效果。采用 R5 0 2压缩机和制冷剂制成 FD- 1冷冻干燥机。本实验冷冻干燥了胶原海绵、菌种及去纤酶。在冻干箱负载或空载情况下蒸发冷凝器温度均可达到 - 4 5℃ ,小冰箱可达到 - 30℃ ,冻干的胶原海绵具有许多孔洞的结构 ,冻干的菌种和去纤酶性能保持良好。 FD- 1冷冻干燥机适用于生物样品中小批量的冷冻干燥     

糖尿病大鼠创面愈合过程中成纤维细胞增殖及Ⅰ型胶原合成减少

目的：观察链脲佐菌素诱导的大鼠糖尿病复合创伤修复过程中成纤维细胞增殖与胶原合成的变化。 方法： 实验采用Wistar大鼠112只，随机分对照组和模型组。模型组大鼠腹腔注射链脲佐菌素（STZ）55 mg/kg，3周后各组动物复合背部2.04 cm²全厚皮切除形成伤口。观察创面愈合时间和愈合率；采用HE染色和免疫组化法观察成纤维细胞和增殖细胞核抗原(PCNA)表达水平；采用苦味酸-天狼星红染色和图像分析技术观察创面Ⅰ、Ⅲ型胶原含量及Ⅰ/Ⅲ型比值。 结果： STZ诱发的糖尿病大鼠复合创伤后创面的愈合时间为(27.13±1.81)d，明显长于对照组（15.25±1.67）d，P<0.01；模型组在创伤第3、7和15 d创面愈合率明显低于对照组，分别P<0.01；在3、5、7和9 d模型组创面成纤维细胞数量和PCNA表达也明显少于对照组，分别P<0.05和P<0.01。两组创面在不同时点上Ⅰ型胶原分布均呈递增趋势，但对照组明显多于模型组，分别P＜0.05；尽管对照组在创伤3、7 d Ⅲ型胶原含量高于模型组，但在创伤3、7和11 d模型组Ⅰ/Ⅲ胶原比值都明显低于对照组，分别P＜0.01。 结论： STZ可能通过影响创面细胞增殖和创面胶原合成，从而导致创面愈合迟缓。     

葡甘聚糖-胶原蛋白-壳聚糖共混膜(I)

用溶液共混法制备了葡甘聚糖-胶原蛋白-壳聚糖(KCCS)共混膜。并用FT-IR,X-RD,SEM及透光率表征了膜的结构,同时测试了膜的抗张强度、断裂伸长率、吸水率、透水汽性、渗透性和吸附性。结果表明:共混膜中葡甘聚糖、胶原蛋白及壳聚糖之间存在着强烈的相互作用和良好的相容性,三者共混明显改善了纯聚合物和二元膜的性能。以共混膜为载体培养内皮细胞,发现共混膜具有良好的细胞相容性,预示着共混膜可作为潜在的组织工程支架材料。     

Matrix metalloproteinase expression in basal cell carcinoma: relationship between enzyme profile and collagen fragmentation pattern

Matrix metalloproteinases (MMPs) with collagenolytic and gelatinolytic activities are up-regulated in basal cell carcinoma. In the present study we demonstrate that the major collagenolytic enzyme detected is MMP-1 (interstitial collagenase) while gelatinolytic enzymes include both MMP-2 (72-kDa gelatinase A) and MMP-9 (92-kDa gelatinase B). Significant fractions of all three enzymes are present as active forms. In spite of the fact that high levels of gelatinolytic enzymes are present, the major fragmentation products resulting from digestion of intact type I collagen are the 1/4 and 3/4 fragments (products of MMP-1-mediated digestion). Thus, it appears that the gelatinolytic enzymes are not capable of degrading the collagen fragments as rapidly as they are produced. Since previous studies have demonstrated that interaction of interstitial fibroblasts with high molecular weight fragments of type I collagen leads to increased MMP production, the present results suggest a mechanism underlying altered function of stromal elements in the connective tissue adjacent to the growing neoplasm.     

The molecular basis for inherited bullous diseases

In the past 5 years enormous progress have been made in our understanding of the molecular basis for a number of inherited skin diseases characterized by easy blistering of the skin and the mucous membranes after minor physical trauma. This increased fragility of the skin or its appendages is due to molecular defects in genes coding for different intra- and extracellular structural proteins which are responsible for mechanical strength at their sites of expression. These diseases encompass the group of epidermolysis bullosa and disorders of cornification such as bullous forms of ichthyosis, palmoplantar keratoderma, and pachyonychia congenita. On the basis of clinical, morphological, and ultrastructural observations the epidermolysis bullosa group has been divided into three major categories. In epidermolysis bullosa simplex blister formation appears within the basal cell layer of the epidermis, and many mutations have been found in the genes of keratin 5 and 14 which are both expressed in basal keratinocytes. Epidermolytic hyperkeratosis leads to an epidermal separation in the suprabasal cell layers. In these patients numerous point mutations have now been described in the suprabasally expressed genes of keratin 1 and 10. In ichthyosis bullosa of Siemens blisters occur in the more upper suprabasal epidermis coincidental with the expression of keratin 2e, and mutations have been detected in the corresponding gene. In epidermolytic palmoplantar hyperkeratosis the suprabasal epidermal splitting is restricted to palms and soles of the patient. In keratin 9, which reveals such an exclusive expression pattern, molecular defects have indeed been recognized. Most recently in two different clinical subtypes of pachyonychia congenita, which is characterized by defective nails and focal palmoplantar hyperkeratosis, point mutations have been found in the genes coding for keratins 6, 16, and 17. In junctional epidermolysis bullosa the separation takes place within the dermal-epidermal basement membrane at the level of the lamina lucida, and mutations have been found in three genes coding for different laminin chains, in the ₄ gene of ₆₄ integrin, and in the gene of collagen XVII. In dystrophic epidermolysis bullosa the tissue separation occurs beneath the basement membrane within the papillary dermis at the level of the anchoring fibrils, and several mutations have been identified in the collagen VII gene. The rapid unraveling of molecular defects in these disabling or even lethal inherited skin diseases makes possible a more precise and earlier prenatal diagnosis, creates new options for suitable therapeutic regimens, and even offers the hope of curing these diseases by means of somatic cell gene therapy.Abbreviations BM Basement membrane - BPAg Bullous pemphigoid antigen - DEB Dystrophic epidermolysis bullosa - EB Epidermolysis bullosa - EBS Epidermolysis bullosa simplex - EHK Epidermolytic hyperkeratosis - EPPK Epidermolytic palmoplantar keratoderma - IBS Ichthyosis bullosa of Siemens - JEB Junctional epidermolysis bullosa - KIF Keratin intermediate filaments - NC Noncollagenous domain - NEPPK Nonepidermolytic palmoplantar keratoderma - PC Pachyonychia congenita