Infrared analysis of bones in magnesium-deficient rats treated with vitamin K<Subscript>2</Subscript>

In this study, we compared the effects of vitamin K₂ menatetrenone on bone mechanical properties in rats fed a low-magnesium (Mg) diet. In addition, the mechanism of bone quality was examined using Fourier transform infrared imaging (FTIRI). Thirty 4-week-old male Wistar rats were divided into three groups: intact, low-Mg-control, and low-Mg-MK-4 groups. Rats in the low-Mg groups were given a diet containing 6 mg/100 g Mg (intact, 90 mg/100 g). After an 8-week-treatment, the cortical bone mineral content (CtBMC), outer perimeter, and endo perimeter of the femoral diaphysis in the low-Mg-control group were significantly higher, while the maximum load (ML) and elastic modulus (EM) were 81% and 50% of those in the intact group, respectively (respectively, P < 0.05). In the low-Mg-MK-4 group, ML and EM were significantly higher than in the low-Mg-control group (P < 0.05), with no differences in CtBMC. The mineral/matrix ratios for the periosteal and central regions in the low-Mg-control group were 162% and 120% of those in the intact group (both, P < 0.05), respectively. MK-4 significantly inhibited these increases (P < 0.05). We found that the mineral/matrix ratios for the periosteal region of the femoral diaphysis were negatively correlated with EM, suggesting that an increase in the mineral/matrix ratio may be involved in the reduction of EM and that MK-4 may improve EM by improving the mineral/matrix ratio.     

The incidence, timing, and predisposing factors of germinal matrix and intraventricular hemorrhage (GMH/IVH) in preterm neonates

Background Germinal matrix and intraventricular hemorrhage (GMH/IVH) is a known complication occurring in the first week of life in preterm neonates. However, the precise time of its occurrence and the ideal time to perform diagnostic imaging studies remain controversial. The purpose of this paper is to address these two issues in our patient population to allocate our resources to those at highest risk.Materials and methods This study included 282 premature newborns (under 37 weeks of gestation) that were admitted to our neonate ICU in a year’s time and screened for GMH/IVH. They were grouped in four categories according to their weight at birth, and according to their gestational age. All patients had a daily cranial ultrasound during the first week. It was then repeated once in the second week and once in the third.Results We found that the incidence of GMH/IVH among preterm neonates was 44.68%. It was inversely related to the weight and the age of the newborn. The onset of bleeding coordinated with the occurrence of hypoxia and respiratory distress requiring mechanical ventilation. The majorities occurred in the first 7 days of life; they were mostly grade I and II according to the Papule classification and silent for the most part. Complications were present in 41% of the survivors.     

猪脱细胞真皮基质修复兔腹壁缺损的实验研究

目的研究猪脱细胞真皮基质修复兔腹壁缺损的效果,探讨异种脱细胞真皮基质应用的可行性。方法健康小白猪1头,取背部及两侧皮肤制备脱细胞真皮基质。26只日本大耳白兔,雌雄不限,体重2.2～2.3 kg,随机分为对照组(n=6)和实验组(n=20)。对照组制备5.0 cm×0.5 cm腹壁缺损,单纯缝合关闭缺损。实验组制备5.0 cm×2.5 cm腹壁缺损,用同样大小的猪脱细胞真皮基质补片(简称"补片")修复,补片基底膜面朝向肠管。术后观察是否有疝形成,比较两组腹腔内脏器粘连情况,以及对照组腹壁肌筋膜单纯缝合处和实验组补片-腹壁肌筋膜吻合处的最大张力,组织学观察补片是否有纤维血管组织长入及其在体内的生物学转归。结果实验动物均无疝形成。术后5周,实验组补片和腹壁融为一体,补片皮肤面和脏器面均有纤维血管组织长入,补片处于新生组织掺入重建过程。实验组1只动物补片和腹腔内脏器粘连较重(2级),5只发生了轻微粘连(1级),12只无粘连(0级);对照组1只轻微粘连(1级),5只无粘连(0级);两组粘连分级比较差异无统计学意义(Z=—0.798,P=0.425)。术后5周,实验组补片-腹壁肌筋膜吻合处的最大张力为(13.0±5.5)N,对照组腹壁肌筋膜单纯缝合处为(13.6±4.0)N,差异无统计学意义(t=—0.410,P=0.683)。组织学观察显示,术后5周,实验组补片中有大量小血管,并有中性粒细胞及淋巴细胞为主的炎性浸润,补片边缘偶见巨噬细胞,补片-腹壁肌筋膜吻合处由纤维结缔组织连接;术后6个月,补片及周围炎性反应消退,胶原纤维结构发生了改建,补片和肌筋膜层由有纤维结缔组织愈合。结论补片修复兔腹壁缺损取得了较好效果,补片-腹壁肌筋膜层愈合,其吻合处的力学强度达到了自体腹壁单纯缝合吻合的力学强度,补片胶原纤维结构发生了改建。     

Intra‐articular injection of hyaluronan restores the aberrant expression of matrix metalloproteinase‐13 in osteoarthritic subchondral bone

Subchondral bone is a candidate for treatment of osteoarthritis (OA). We investigated the effects of intra‐articular injection of hyaluronan (IAI‐HA) on subchondral bone in rabbit OA model. OA was induced by anterior cruciate ligament transection, with some rabbits receiving IAI‐HA. OA was graded morphologically, and expression of mRNA was assessed by real‐time RT‐PCR. Tissue sections were stained with hyaluronan‐binding protein, and penetration of fluorescent hyaluronan was assessed. The in vitro inhibitory effect of hyaluronan on MMP‐13 was analyzed in human osteoarthritic subchondral bone osteoblasts (OA Ob) by real‐time RT‐PCR and ELISA. Binding of hyaluronan to OA Ob via CD44 was assessed by immunofluorescence cytochemistry. Expression of MMP‐13 and IL‐6 mRNA in cartilage and subchondral bone, and morphological OA grade, increased over time. IAI‐HA ameliorated the OA grade and selectively suppressed MMP‐13 mRNA in subchondral bone. IAI‐HA enhanced the hyaluronan staining of subchondral bone marrow cells and osteocyte lacunae. Fluorescence was observed in the subchondral bone marrow space. In OA Ob, hyaluronan reduced the expression and production of MMP‐13, and anti‐CD44 antibody blocked hyaluronan binding to OA Ob. These findings indicate that regulation of MMP‐13 in subchondral bone may be a critical mechanism during IAI‐HA. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:354–360, 2011     

祛毒颗粒对5/6肾切除大鼠肾脏皮质MMP-2、TIMP-2、ECM及足细胞超微结构的影响

目的：观察祛毒颗粒对5/6肾切除大鼠肾皮质基质金属蛋白-2（matrix metalloproteinase-2,MMP-2）和金属蛋白酶组织抑制物-2（tissue inhibitor of metalloproteinase-2,TIMP-2）蛋白表达、细胞外基质（extracellular matrix,ECM）积聚和足细胞超微结构的影响。方法：将55只Wistar大鼠随机取10只为正常对照组,余用5/6肾切除法建立慢性肾衰竭（CRF）动物模型,将造模成功后的大鼠随机分为模型组、尿毒清颗粒组（简称对照组）、祛毒颗粒低剂量组（简称低剂量组）、祛毒颗粒高剂量组（简称高剂量组）,每组10只,分别给与相应浓度和剂量的药物,实验期间测定大鼠的尿蛋白、肾功能,治疗12周后观察其肾脏病理改变,PAS染色评价肾小球硬化程度,免疫组化法检测肾小球Ⅳ型胶原（ColⅣ）、纤连蛋白（FN）和MMP-2、TIMP-2蛋白表达,电镜观察足细胞超微结构。结果：祛毒颗粒能明显减少5/6肾切除大鼠尿蛋白量（P〈0.05）,改善肾功能;减轻肾脏病理损害;PAS染色显示,祛毒颗粒治疗后肾小球阳性面积与肾小球总面积比值、肾小球硬化指数明显下降（P〈0.01）;免疫组化检查显示祛毒颗粒能抑制了FN、ColⅣ在肾组织的表达（P〈0.01）,下调TIMP-2蛋白表达,增加MMP-2活性,减轻ECM积聚;电镜观察显示,祛毒颗粒能减少足细胞脱落,减轻足突融合,保护足细胞形态。结论：祛毒颗粒通过调整5/6肾切除大鼠肾皮质MMP-2、TIMP-2的表达,促进ECM降解,减轻ECM集聚,保护足细胞,起到减轻肾小球硬化的作用。     

血管生成拟态与肿瘤

近年来,人们发现了一种新的肿瘤血供形式——血管生成拟态,其与经典的肿瘤血供模式完全不同.这一发现对完善肿瘤的血供机制,改善肿瘤的治疗和预后具有重要的意义.本文主要就其结构、形成机制、对临床肿瘤治疗的意义进行综述.     

Structure and biology of the intervertebral disk in health and disease

The intervertebral disks along the spine provide motion and protection against mechanical loading. The 3 structural components, nucleus pulposus, annulus fibrosus, and cartilage endplate, function as a synergistic unit, though each has its own role. The cells within each of these components have distinct origins in development and morphology, producing specific extracellular matrix proteins that are organized into unique architectures fit for intervertebral disk function. This article focuses on various aspects of intervertebral disk biology and disruptions that could lead to diseases such as intervertebral disk degeneration.     

和解聚散方对单侧输尿管梗阻肾间质纤维化大鼠细胞外基质表达的影响

目的:研究和解聚散方对单侧输尿管梗阻(unilateral ureteral obstruction,UUO)大鼠肾间质纤维化(renal interstitial fibrosis,RIF)、细胞外基质(extracellular matrix,ECM)、纤维连接蛋白(FN)和Ⅳ型胶原(Col Ⅳ)表达的影响.方法:...     

热休克蛋白47在转化生长因子β1诱导肾小管间质纤维化中的作用

目的 探讨热休克蛋白47（HSP47）在肾小管间质纤维化中的作用及其可能机制。 方法 常规培养人肾小管上皮细胞（HK-2）,分为对照组、转化生长因子β1（TGF-β1）组、HSP47-siRNA组。RT-PCR检测HSP47、胶原Ⅳ、纤连蛋白（FN）、组织型纤溶酶原激活物抑制剂1（PAI-1）的mRNA表达。Western印迹检测HSP47、胶原Ⅳ、FN蛋白表达。ELISA检测PAI-1的蛋白量。 结果 HK-2细胞有HSP47表达。不同浓度TGF-β1（0、2.5、5、10 μg/L）干预不同时间（12、24、48 h）时,HSP47基因和蛋白表达呈浓度和时间依赖性增高,10 μg/L TGF-β1干预HK-2细胞48 h时,HSP47 mRNA和蛋白表达最强。不同浓度 TGF-β1（0、5、10 μg/L）干预HK-2不同时间（12、24、48 h）时,胶原Ⅳ、FN 、PAI-1 mRNA和蛋白表达亦呈浓度和时间依赖性增高,10 μg/L TGF-β1作用48 h时,3者mRNA和蛋白表达最强。与TGF-β1组比较,HSP47-siRNA组的HSP47、胶原Ⅳ、FN、PAI-1 mRNA和蛋白表达都明显下调。 结论 HSP47可促进肾小管间质纤维化,其机制可能与上调胶原Ⅳ、FN、PAI-1表达有关。