Attenuation of intracavitary applicators in 192Ir-HDR brachytherapy

Unlike the penetrating monoenergetic 662 keV gamma rays emitted by 137Cs LDR sources, the spectrum of 192Ir used in HDR brachytherapy contains low-energy components. Since these are selectively absorbed by the high-atomic number materials of which intracavitary applicators are made, the traditional neglect of applicator attenuation can lead to appreciable dose errors. We investigated the attenuation effects of a uterine applicator, and of a set of commonly used vaginal cylinders. The uterine applicator consists of a stainless steel source guide tube with a wall thickness of 0.5 mm and a density of 8.02 g/cm3, whereas the vaginal cylinders consist of the same stainless steel tube plus concentric polysulfone cylinders with a radius of 1 or 2 cm and a density of 1.40 g/cm3. Monte Carlo simulations were performed to compute dose distributions for a bare 192Ir-HDR source, and for the same source located within the applicators. Relative measurements of applicator attenuation using ion-chambers (0.125 cm3) confirmed the Monte Carlo results within 0.5%. We found that the neglect of the applicator attenuation overestimates the dose along the transverse plane by up to 3.5%. At oblique angles, the longer photon path within applicators worsens the error. We defined attenuation-corrected radial dose and anisotropy functions, and applied them to a treatment having multiple dwell positions inside a vaginal cylinder.     

db-cAMP对转化细胞增殖抑制及其对CaM水平和PKⅡ活性的影响

目的　探讨双丁酰 环核苷酸 (db cAMP)对转化细胞增殖及细胞表型作用的机理。　方法　以流式细胞光度术 (flowcytometry ,FCM)、软琼脂集落形成、放射免疫、Northern印迹和激酶活性分析等方法观察db cAMP对转化的C3H1 0 T1 2 小鼠成纤维细胞增殖、细胞表型、钙调素 (calmodulin ,CaM)表达及蛋白激酶Ⅱ (proteinkinaseⅡ ,PKⅡ )活性的影响。　结果　db cAMP(1mmol L)使C3H1 0 T1 2 转化细胞增殖及软琼脂集落形成能力受到显著抑制 ,转化细胞中CaM的表达及PKⅡ活性明显高于正常细胞 ,经db cAMP处理后也受到明显抑制。　结论　细胞转化及cAMP的诱导分化作用与PKⅡ活性的改变有密切相关性     

Expression and changes of HSP70 in the rat forebrain subjected to gamma knife (100Gy) irradiation targeted on the caudate putamen and survived for different times

Forebrain heat shock protein 70 (HSP70) immunohistochemical reactivity was investigated in rats subjected to gamma knife irradiation focusing on the right caudate putamen nucleus. The forebrain sections of all experimental animals were processed with anti-HSP70 antiserum and then by avidin-biotin peroxidase complex immunohistochemistry after gamma ray irradiation with a dose of 100Gy and they each survived for different times (from 30 min to 30 days). Some neurons, glial cells, and endothelial cells were HSP70-like immunoreactivity (HSP70-LI) positive. HSP70-LI was mainly distributed in the target area of irradiation, as well as in non-target regions, e.g. the cortex, hippocampus, and hypothalamus, etc. The expression and change of HSP70-LI from 3 h to 30 days after irradiation followed the following rules: (1) Within 3 to 24 h, the dilated vessels with HSP70-LI endothelial cells were found at first, and a few lightly stained HSP70-LI neurons and glias were observed in the target and non-target regions; (2) In 3-7 days, darkly stained HSP70-LI neurons and glias were apparently increased and formed an expression peak. From 14 to 30 days, HSP70-LI cells were distinctly decreased and became weakly stained or negative. These results suggested that although the irradiation target of the gamma knife was localized, the response to irradiation occurred extensively.     

^32P局部照射预防猪冠状动脉再狭窄研究

目的：评价^32P灌注球囊预防再狭窄的有效性、可行性和安全性。方法：对猪冠状动脉左前降支行过度球囊扩张术后,治疗组以^32P作血管内照射,对照组作假照射。术后35d收获目标血管、检测血管形态、细胞增殖百分比等。结果：治疗组血管腔面积较对照组明显增大（P＜0．01）,新生内膜面积、血管狭窄程度和各层PCNA阳性细胞明显减小（P均＜0．01）。结论：^31P灌注球囊照射预防冠状动脉再狭窄有效、安全而且可行。     

胆汁泡蛋白ELISA检测法的建立与初步临床应用

目的 建立胆汁泡蛋白快速检测法,筛选有效的胆石症防治手段。方法 获取３３．５ｋｄ胆汁泡蛋白,通过微量抗原免疫法获得高效价抗体,建立ＥＬＩＳＡ标准曲线;并应用ＥＬＩＳＡ法测定正常人、胆石症患者胆汁和血清中泡蛋白含量,同时观察不同溶石防药和利胆冲剂、胆酸钠等对泡蛋白的影响。结果 建立了ＥＬＩＳＡ标准曲线,其曲线方程为Ｙ＝０．０３５Ｘ（ｒ＝０．９９）;正常人胆汁和血清中３３．５ｋｄ泡蛋白含量都明显较胆固     

High Expression of Insulin-like Growth Factor Ⅱ (IGF-Ⅱ) Using Bac-to-Bac Expression System

Ｈｕｍａｎｉｎｓｕｌｉｎ ｌｉｋｅｇｒｏｗｔｈｆａｃｔｏｒ Ⅱ (ＩＧＦ Ⅱ )ｉｓａ 6 7ａｍｉｎｏａｃｉｄｓｉｎｇｌｅ ｃｈａｉｎｐｅｐｔｉｄｅ ,ｗｈｉｃｈｉｓｉｎｖｏｌｖｅｄｉｎｆｅｔａｌｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐ ｍｅｎｔ[1] .Ｔｈｅｇｒｏｗｔｈ ｐｒｏｍｏｔｉｎｇｐｒｏｐｅｒｔｉｅｓｏｆＩＧＦ Ⅱ ,ａｓｗｅｌｌａｓｔｈｅｉｒｓｔｒｕｃｔｕｒａｌｈｏｍｏｌｏｇｙｔｏｐｒｏｉｎｓｕｌｉｎａｎｄＩＧＦ Ⅰａｒｅｒｅｆｌｅｃｔｅｄｉｎｔｈｅｎａｍｅｏｆｔｈｅｐｅｐｔｉｄｅｓ .Ｉｔｉｓａｌｓｏｈｅｌｐｆ…     

国产房水引流物置入术治疗难治性青光眼远期疗效观察

１９９３年７月～１９９８年１月为１０３例（１０６只眼）难治性青光眼患者施行国产房水引流物（ＨＡＤ）置入术。术后平均随访３２８月。术后１年时平均眼压２２±１．４ｋＰａ。术后１～５年的手术成功率分别为８３８％,８０４％,７７１％,７１０％及６４３％。术中联合应用丝裂霉素Ｃ的病例,其术后１年时的成功率为８９５％。术后常见的并发症有持续性浅前房,局限性脉络膜脱离及眼压升高等。认为ＨＡＤ可用于治疗难治性青光眼。     

Patient,Provider, and Treatment Factors Associated with Poor-Quality Care for Schizophrenia

Interventions are needed to improve the quality of care for schizophrenia. However, in designing these interventions it would be helpful to understand better which patients are at highest risk for poor-quality care and why care for this disorder is often of poor quality. We study the extent to which patient and treatment factors are associated with poor-quality care in 224 patients randomly sampled from two mental health clinics. Quality of medication management is evaluated using an established method based on national treatment recommendations. Multivariate regression is used to study the effect of patient and treatment factors on treatment quality, controlling for provider. Risk for poor-quality care was greater for patients who were more severely ill, older, and less compliant with treatment recommendations. There were trends toward poor management of symptoms in men and substance abusers, and poor management of side effects in Black patients. Provision of poor-quality care was associated with failure to document symptoms and side effects in the medical record. Interventions to improve care for schizophrenia should attend to the need for accurate clinical assessment and strategies for managing challenging clinical situations.     

Interleukin-12 enhances the sensitivity of human osteosarcoma cells to 4-hydroperoxycyclophosphamide by a mechanism involving the Fas/Fas-ligand pathway.

Cyclophosphamide (CY) and its derivative ifosfamide are alkylating agents used to treat osteosarcoma (OS). The purpose of these studies was to determine whether alkylating agents affect the expression of Fas ligand (FasL) and whether interleukin 12 enhances the sensitivity of human OS cells to alkylating agents. 4-Hydroperoxycyclophosphamide (4-HC), the preactivated CY compound, and 4-hydroperoxydidechlorocloclophosphamide (4-HDC), its nonalkylating analogue, human OS LM6 cells, and a clone of cells derived by transfection with the interleukin 12 gene (LM6-#6) were used for these studies. Incubation of LM6 and LM6-#6 with 10 micro M 4-HC increased the expression of FasL mRNA (2.5- and 3.0-fold, respectively). By contrast, 4-HDC, Adriamycin (ADR), cisplatin (CDP), and methotrexate (MTX) had no effect on FasL mRNA expression. Increased FasL expression after treatment with 4-HC was also demonstrated by immunohistochemistry and flow cytometry. Drug-induced FasL was functional and mediated cell death. We examined the effect of FasL up-regulation by 4-HC on LM6 and LM6-#6 cells. Flow cytometry showed that LM6-#6 cells expressed 2.2-fold more Fas than LM6 cells. Cytotoxicity of 4-HC, 4-HDC, ADR, CDP, and MTX on LM6, LM6-neo, and LM6-#6 were quantified. Colony-forming assay revealed an IC(50) of 2.10 micro M for 4-HC in LM6-neo cells compared with 0.41 micro M in LM6-#6 cells. The IC(50) for 4-HDC, ADR, CDP, and MTX were not significantly different between the two cell lines. We concluded that the increased expression of Fas enhanced LM6-#6 sensitivity to 4-HC. These data indicate that Fas/FasL may be involved in the cytotoxic pathway of CY. Combining biological agents with chemotherapeutic agents that have complementary Fas/FasL pathway actions may offer new therapeutic alternatives.