Characterization of intramuscular collagen in the mammalian left ventricle

Summary Left ventricular collagen of various mammals (cat, cow, dog, pig, and rat) was successively extracted with neutral salt, and dilute acid solutions, and limited pepsin digestion. The distribution of the various types of collagen molecules in pepsin-solubilized ventricular collagen was analyzed electrophoretically on SDS-polyacrylamide gels in the presence of 3.6 M urea.Yields of dilute-acid-soluble collagen were only 0.4 to 0.6% of the total ventricular collagen, and less than 0.1% with neutral salt solution. Approx. 55–90% of the total collagen was extracted by limited pepsin digestion.Disc patterns of pepsin-soluble collagen revealed the presence of dimeric and trimeric components, as well as higher-molecular-weight aggregates in all samples of nonreduced and reduced ventricular collagen. Taken together, these findings suggest the presence of an extensive interchain and intermolecular cross-linking network in left ventricular collagen.Comparison of electrophoretical disc gel patterns of reduced and nonreduced pepsin-solubilized collagen indicated that left ventricular collagen is heterogenous in nature, consisting of a mixture of type I and type III collagen. It was evident that primarily type I components occur in ventricular collagen. The components of type III collagen molecules occurred in all investigated left ventricles in varying and consistently appreciably lower amounts. The proportions of type III and type I collagen vary in left ventricular tissue of different species.Supported by grants from the Deutsche Forschungsgemeinschaft     

Effects of Cyclophosphamide on the Formation and Solubility of Collagen

Abstract: The effects of low (5 mg/kg × 7) and high (20 or 30 mg/kg × 7) doses of cyclophosphamide on the formation an solubility of collagen in subcutaneous, porous implants, bones and incisional skin wounds were studied in young, male rats. At the 5 mg/kg schedule, effects from the drug were only detected as an increased solubility of collagen in implant connective tissue. At the 20 mg/kg schedule, there was a significant reduction of the synthesis and solubility of collagen in bones and in skin wounds. The 30 mg/kg schedule significantly depressed all the parameters studied except the specific activity of hydroxyproline in implants. Collagen stability seems to be impaired at low dose levels, whereas one of the main effects of high doses appears to be inhibition of collagen synthesis.     

Biochemical Changes in Bone Grafts Stabilized with Rigid Plates: I. Cancellous Grafts

The effect of rigid plate fixation on the chemical composition of cancellous interposition grafts was studied in rabbit tibio-fibular bones.

The concentrations of hexosamines and, to a lesser degree, of hydroxyproline and nitrogen, were high in the graft for the first 6 weeks, decreased from weeks 6 to 12, but remained higher than the corresponding values for the controls throughout the experiment (52 weeks). The ratio of hexosamines to hydroxyproline was highest for the graft at 3 weeks, indicating formation of cartilage and osteoid.

The initially low calcium concentration of the graft increased by 35 per cent from weeks 1 to 6, decreased from weeks 6 to 12, and remained below normal thereafter in comparison with corresponding values for the cortical host bone. The ratio of calcium to hydroxyproline increased throughout the experiment, reflecting maturation of the graft to lamellar bone.

Thus, biochemically the early incorporation of rigidly fixed cancellous interposition grafts resembles the healing of unimmobilized fractures by callus formation.     

Obstetrical complications in a patient with the Marfan syndrome

A case history of a pregnant patient with the Marfan syndrome is presented. During pregnancy regular echocardiographic examinations were performed, showing a slight increase in the aortic root diameter 1 month after delivery. The hydroxyproline content of the amniotic fluid appeared to be significantly elevated; however, the baby did not seem to be affected by the Marfan syndrome. After delivery we noted a recto-vaginal perforation, which has not been described in deliveries of Marfan patients before. Pregnancy in a Marfan patient is a hazardous situation, with a 10–40% fatal outcome according to the literature. Regular echocardiographic control is necessary to evaluate the cardiac risk.     

大鼠肺组织羟脯氨酸测定方法及其应用

在参考并改进其他组织中羟脯氨酸（Ｈｙｐ）测定方法的基础上，对大鼠肺组织Ｈｙｐ测定方法的实验条件进行了研究。结果表明，①样品酸水解时间为２－３ｈ；②测量前无需调ｐＨ；③显色反应的温度和时间分别为８０℃和１０ｍｉｎ；④显色后无需冰水冷却。该方法重复性好，回收率高，在放射性肺炎研究中应用时，观察到肺组织Ｈｙｐ含量随照后时间的动态变化及补硒保护均有明显规律。     

The effect of aluminum on the metabolism of embryonic chick bone in tissue culture

The effect of aluminum (Al) on bone metabolism was assessed in organ cultures of embryonic chick bone. Al of 10^?4 M and above caused an inhibitory effect on mineralization without inhibiting matrix formation and a stimulative effect on demineralization without stimulating matrix degradation. Therefore, Al was shown to influence the mineral metabolism of bone.     

The effect of short-term calcitonin administration on biochemical bone markers in patients with acute immobilization following hip fracture

The effect of salmon calcitonin on changes in mineral metabolism was studied in 40 elderly patients with recent hip fracture. All patients underwent surgery (internal fixation) 1 week after admission and were randomly divided into two equal groups: group A, which received no treatment, and group B, which received 100 IU/day salmon calcitonin intramuscularly for 2 weeks starting on admission. Blood and 24-h urine parameters of mineral metabolism were measured on admission and at the end of weeks 1 and 2. No intra- or intergroup changes in serum calcium, phosphorus or alkaline phosphatase were observed. At the end of week 2 biochemical markers of bone resorption (urinary calcium and hydroxyproline) had significantly increased in group A and significantly decreased in group B, indicating a reduction in bone resorption in group B. Urinary phosphorus had also increased in group B, possibly due to the phosphaturic effect of calcitonin. It is concluded that immobilization resulting from a hip fracture, and possibly surgery itself, causes significant changes in biochemical markers of bone resorption. Calcitonin successfully reverses these changes and may also be effective in preventing subsequent bone loss, particularly in patients who cannot be remobilized immediately.     

卡托普利逆转高血压大鼠心血管重建过程的抗交感神经作用(英文)

已有心血管肥厚的SHR,给予卡托普利(Cap)20 mg·kg~(-1)·d~(-1)(A组);可乐定(Clo)30μg·kg~(-1)·d~(-1)(B组);Cap 20 mg·kg~(-1)·d~(-1)加 Clo 30 μg·kg~(-1)·d~(-1)(C组);24周后处死,各组的SBP均明显下降,但未达WKY水平,Cap加Clo无更强降压作用,A组和C组的LVH明显逆转,两组间无差别,单用Clo不逆转SHR的LVH,各组的心肌NE明显降低,单用Cap的作用最强,说明Cap具有抗交感神经作用,且不因联用Clo而加强。     

Synthesis and Solubility of Collagen in Rats during Recovery after High-dose Cyclophosphamide Administration

Abstract: The metabolism of collagen and mineral was studied during a nine-day postmedicational period in young, male rats receiving high-dose intraperitoneal cyclophosphamide treatment every second day for 12 days. Two days after ending medication the white blood cell counts (WBC) were reduced by about 70%. Both synthesis and solubility of collagen were suppressed by the present medication 2 days after termination of treatment. This suppression continued throughout the 9-day postmedicational period in bones, whereas in connective tissue of porous, ceramic implants both total collagen and the amount of salt soluble collagen regained normal values 9 days after cessation of treatment. Increased mineralization was found 2 days after ending medication and this high degree of mineralization persisted during the postmedicational period studied. Serum albumin levels were reduced and no increases were detected during the postmedicational period. The suggestion is made that the general protein synthesis is affected by high-dose cyclophosphamide administration.     

苦杏仁苷对二甲基亚硝胺诱导的大鼠肝纤维化的防治作用

目的：探讨苦杏仁苷对二甲基亚硝胺（DMN）诱导的大鼠肝纤维化的防治作用。方法：采用Wistar雄性大鼠,以腹腔注射DMN诱导大鼠肝纤维化模型。在造模4周后,将造模大鼠按体重分层随机分为模型组、苦杏仁苷组及对照药秋水仙碱组,每组10只,灌胃用药两周后取材。观察检测以下指标：①末次体重、肝脾比值;②肝组织羟脯氨酸含量;③肝功能指标：血清丙氨酸氨基转移酶（ALT）、门冬氨酸氨基转移酶（AST）、谷胺酰转肽酶（GGT）活性;白蛋白（Alb）、总胆红素（TBil）含量;④肝组织天狼星红染色及HE染色;⑤肝组织脂质过氧化指标：超氧化物歧化酶（SOD）、丙二醛（MDA）、还原型谷胱甘肽（GSH）、谷胱甘肽过氧化物酶（GSH-Px）。结果：①模型组大鼠肝组织羟脯氨酸含量与正常组相比显著升高（P〈0.01）;与模型组相比,苦杏仁苷及秋水仙碱治疗组大鼠肝组织羟脯氨酸含量显著降低（P〈0.01）;②天狼星红染色显示模型组大鼠窦周胶原沉积明显,肝小叶间形成较厚汇管区和中央静脉间的纤维间隔,可见较多完整的假小叶,HE染色结果显示模型组大鼠肝细胞水肿明显,汇管区结缔组织有不同程度增生,肝组织中有炎性细胞浸润,窦壁细胞增生明显;苦杏仁苷治疗组和秋水仙碱对照组与模型组相比炎症缓解、胶原纤维增生程度分期显著降低（P〈0.05）;③模型组大鼠血清ALT、AST、GGT活性及TBil含量显著升高,Alb含量显著降低（P〈0.01）;苦杏仁苷组与秋水仙碱组大鼠血清ALT、AST活性显著降低（P〈0.01或P〈0.05）;④与正常组比较,模型组大鼠肝组织SOD活性、GSH含量及GSH-Px活性显著降低,MDA含量显著升高（P〈0.05）;苦杏仁苷能显著升高模型大鼠肝组织GSH活性（P〈0.05）,秋水仙碱则能显著升高GSH、GSH-Px活性。结论：苦杏仁苷对DMN诱导的大鼠肝纤维化有显著改善作用。