Case of postradiation osteosarcoma with a short latency period of 3 years

Osteosarcoma is one of the neoplasms that may occur following exposure to radiation. A case of osteosarcoma arising in the craniofacial bone with a short latency period of 3 years after radiotherapy for maxillary squamous cell carcinoma is described. A 64-year-old-man underwent right partial maxillectomy and chemoradiotherapy due to squamous cell carcinoma of his right maxillary sinus. Histologically, the tumor was composed of moderately differentiated squamous cell carcinoma with a component of spindle cell carcinoma. Three years later, osteosarcoma developed in the craniofacial bone within the irradiation field of the first tumor. Detailed histological examination demonstrated that there was no component of osteosarcoma in the first tumor or squamous cell carcinoma in the second tumor. Radiation-induced osteosarcoma usually occurs after a long latency period of more than 10 years after the radiotherapy. In this case, osteosarcoma was possibly a radiation-induced osteosarcoma with a short latency period of 3 years.     

低强度脉冲电磁场对大鼠骨质疏松的影响

目的：观察低强度脉冲电磁场（pulsed electromagnetic fields，PEMFs）对去卵巢诱导骨质疏松症的大鼠生化指标和骨应力的影响。方法：雌性SD大鼠30只，随机等分为3组（n=10），分别为假手术组（Sham）、骨质疏松模型组（Model）、脉冲电磁场照射组（PEMFs）。经适应4wk后，在25mg·Kg^-1戊巴比妥钠腹腔麻醉下，Model组和PEMFs组摘除双侧卵巢．Sham组找到但不切除卵巢。各实验组均在相同环境下饲养，模型制备4wk后开始治疗，由GZY型低强度低频率脉冲电磁场发生仪产生低频脉冲磁场，根据实验要求，我们使用亥姆霍兹线圈形成均匀磁场，PEMFs组经照射刺激治疗，频率14．3Hz，场强2Gs．日照8h。Model组和Sham组正常饲养。治疗8wk后，对各组大鼠血清、尿液中ALP和Ca以及骨应力进行检测。结果：（1）ALP、Ca检测结果：与Model组相比，PEMFs组ALP值、Ca值差异均有统计学意义（P〈0．05）。其中，血清中ALP值，Model组为（275．16±228，57），PEMFs组为（179．30±87．68）；Ca值，Model组为（2，66±0，13），PEMFs组为（2．52±0．05）。（2）骨应力检测结果：Model组为（923．60±34．15Pa），PEMFs组为（1152．85±118，20Pa），组间差异有统计学意义（P〈0．05）。结论：研究发现，PEMFs对于促进骨重建、提高Ca吸收和骨应力恢复具有积极作用。     

Oral administration of muscle derived small molecules inhibits tumor spread while promoting normal cell growth in mice

Tumor metastases are extremely rare in striated muscles. This is surprising given the fact that this tissue constitutes 60% of body weight. The present study focuses on small molecules produced and secreted by muscle cells which possess anti-cancer activity in vivo. Recently we have shown that a low molecular weight fraction (<1000 Dalton) of skeletal muscle cell conditioned medium (muscle factor-MF), markedly inhibits the proliferation of carcinoma, sarcoma or melanoma cell lines in vitro. The MF exerts a cytostatic effect on tumor cell growth and arrests the cells in the G0/G1 of the cell cycle. However, normal cell proliferation, such as bone marrow and fibroblasts, was stimulated following incubation with MF. In this study, the effect of orally administered MF on melanoma and sarcoma growth was examined in mice. The administration of MF to mice inoculated intravenously with melanoma (B16–F10) or sarcoma (MCA-105) cells, resulted in a statistically significant inhibition of metastatic lung foci. In a different model, melanoma was induced in the foot pad and after development of a local lesion, the leg was amputated. A prolonged survival time was observed in the MF treated groups. Since the MF stimulated bone marrow cell proliferation in vitro, we decided to test its efficacy as an inhibitor of the myelotoxic effect exerted by chemotherapy, in vivo. MF, administered after chemotherapy, restored the number of white blood cells and yielded an increased percentage of neutrophils compared with the decline in these parameters after administration of chemotherapy alone. Thus, it is indicated that MF exerted a systemic anti tumor and chemoprotective effect when given orally. It can be concluded that it is bioavailable and is not biodegradable in the digestive system. MF may be considered as a potential therapy for the prevention of tumor spread. This revised version was published online in July 2006 with corrections to the Cover Date.     

下颌骨的应力迹线与骨小梁构筑的关系

根据下頜光弹的等倾线图,描绘出主应力迹线规迹。在下颌侧位X线照片和去除唇侧及颊侧密质骨板的标本上,观察骨密质和松质的配布,以及骨小梁的排列和方向,试行探讨骨小梁方向与主应力迹线的关系。用光弹法求得的主应力迹线有两个系列:S_1系在下颌体近水平方向,在下颌支近垂直方向分布;S_2系力线与S_1系诸力线呈正交。在标本和X线照片上,主应力迹线规迹不同程度地在骨小梁的排列上有所反映。     

bFGF在骨组织工程学中的研究进展

碱性成纤维细胞生长因子 (b FGF)是近年来研究较为广泛的生长因子之一 ,对骨组织有着广泛的生物学效应。本文就 b FGF的研究进展及其目前在骨组织工程学研究方面的应用做一综述     

Sclerosteosis: report of a case in a black African man

Sclerosteosis is a rare genetic disorder of bone modelling, similar to, but distinct from, van Buchem disease; it has been described almost exclusively in Afrikaners of South Africa, a white population of Dutch ancestry. Isolated cases have been reported in a girl in Japan, a boy in Spain, and in multiracial families in Brazil and USA.
Here we report a case of sclerosteosis in a black man born in Senegal. He presented with the full features of the disease: tall stature; syndactyly; nail dysplasia; massive sclerosis of the long tubular bones, the ribs, the pelvis and the skull; multiple cranial nerve involvement: optic atrophy, facial palsy and trigeminal neuralgia. Radiologic examination, visual and brainstem auditory evoked potentials, computerized tomography and magnetic resonance imaging of the skull were performed. This seems to be the first case of the disease in a black African individual, with no known relationship with Dutch ancestry.     

异种骨内固定器力学性能的实验研究

目的了解牛骨材料及其构件的力学强度[抗拉、抗压、抗折(弯曲)和抗扭(剪切)强度].方法将材料分为天然、处理和构件(即产品)三组并制成标准试件,用规定设备按标准方法进行检测.结果(1)牦牛股骨拉伸、压缩、抗折、扭转极限应力分别为106.35±3.45、127.60±2.65、225.9±4.1、53.45±1.55(MPa),胫骨拉伸、压缩、抗折、扭转极限应力分别为114.96±1.46、184.75±3.25、211.35±2.45、51.9±0.5(MPa).湖区水牛胫骨拉伸、压缩、抗折、扭转极限应力分别为1 28.1±11、195.8±9.4、167.4±1 2.7、54.25±0.75(MPa).(2)E0气薰灭菌对牛骨材料的力学性能无明显影响,幅照灭菌对牛骨材料的力学性能稍有影响.(3)处理后,牛骨螺钉、圆钉的抗折强度较材料有所降低,而抗拉强度、抗压强度、抗扭强度变化不大.结论牛骨是一种力学性能良好,适合制作内固定构件的高强度生物材料.     

Morphometric analysis of the thoracic and lumbar spine in Japanese on the use of pedicle screws

The pedicle screw and hook have become popular instruments in treating spinal deformity and disease. This study gathered morphological data on thoracic and lumbar spines in a Japanese population that should serve as useful reference for posterior instrumentation surgery. One hundred and three dry bones were used to investigate the morphology of pedicle and facet in thoracic and lumbar spines. Measurements included the diameter and axial length of pedicle from T8 to L5, height and width of facets and thickness of articular processes from T1 to T12, and axial angle of pedicle from T1 to L5. The diameter and axial length of pedicle were smallest at T8, diameter was largest at L5 and axial length was largest at L3. Height of facets and thickness of articular processes were largest at T12. Men tended to have larger pedicles and facets than women. Transverse angle of pedicle was smallest at T12. These precise data may provide useful information when performing posterior instrumentation surgery and when developing new spinal implant systems for Asians.     

Comparison of hprt and lacI mutant frequency with DNA adduct formation in N-hydroxy-2-acetylaminofluorene-treated Big Blue rats

N-Hydroxy-2-acetylaminofluorene (N-OH-AAF) is the proximate carcinogenic metabolite of the powerful rat liver carcinogen 2-acetylaminofluorene. In this study, transgenic Big Blue(R) rats were used to examine the relationship between in vivo mutagenicity and DNA adduct formation by N-OH-AAF in the target liver compared with that in nontarget tissues. Male rats were given one, two, or four doses of 25 mg N-OH-AAF/kg body weight by i.p. injection at 4-day intervals, and groups of treated and control rats were euthanized up to 10 weeks after beginning the dosing. Mutant frequencies were measured in the spleen lymphocyte hprt gene, and lacI mutant frequencies were determined in the liver and spleen lymphocytes. At 6 weeks after beginning the dosing, the hprt mutant frequency in spleen lymphocytes from the four-dose group was 16.5 x 10(-6) compared with 3.2 x 10(-6) in control animals. Also at 6 weeks, rats given one, two, or four doses of N-OH-AAF had lacI mutant frequencies in the liver of 97.6, 155.6, and 406.8 x 10(-6), respectively, compared with a control frequency of 25.7 x 10(-6); rats given four doses had lacI mutant frequencies in spleen lymphocytes of 55.8 x 10(-6) compared with a control frequency of 20.4 x 10(-6). Additional rats were evaluated for DNA adduct formation in the liver, spleen lymphocytes, and bone marrow by (32)P-postlabeling. Adduct analysis was conducted 1 day after one, two, and four treatments with N-OH-AAF, 5 days after one treatment, and 9 days after two treatments. N-(Deoxyguanosin-8-yl)-2-aminofluorene was the major DNA adduct identified in all the tissues examined. Adduct concentrations increased with total dose to maximum values in samples taken 1 day after two doses, and remained essentially the same after four doses. In samples taken after four doses, adduct levels were 103, 28, and 7 fmol/microg of DNA in liver, spleen lymphocytes, and bone marrow, respectively. The results indicate that the extent of both DNA adduct formation and mutant induction correlates with the organ specificity for N-OH-AAF carcinogenesis in the rat. Environ. Mol. Mutagen. 37:195-202, 2001. Published 2001 Wiley-Liss, Inc.