Alpha-particle Irradiation of Haemopoietic Tissue in Pre- and Postnatal Mice

Summary

Pregnant mice (at 13 days gestation) and age-matched controls were injected with 30 kBq ²³⁹Pu/kg and the distribution of plutonium in maternal and foetal tissues measured. Approximately 2% of the activity injected into the mother reached each foetus in 24 h, 95% of which was contained in membranes and placenta. The concentration of plutonium in foetal liver was 3 times the average foetal body concentration; both liver and body concentrations in the foetus increased by the end of gestation. Each pup accumulated only 0.01% extra injected activity after 9 days lactation and, as the resulting concentrations in the neonatal skeletion were low, we conclude that the greatest haemopoietic risk to the offspring from mid-term contamination in utero is in the foetal liver (which received an average dose of 10–14 mGy between the time of mid-term contamination and birth). By the end of gestation about one-quarter of the original activity was transferred to foetal tissues from the maternal liver and skeleton. No significant changes in maternal distribution were detected as a result of lactation. The results of this study are discussed, along with a compilation of previously published data.     

Diurnal Rhythmicity in the Sensitivity of Haemopoietic Cells to Whole-body Irradiation of Mice

Summary

When mice are maintained on a light-dark cycle in which the light begins at 06.00 and ends at 18.00 hours, endogenous spleen colony-forming cells are most radiosensitive at 02.00 and most radioresistant at 22.00 hours. There are three cycles of radiosensitivity with a cycle time of 8 hours. The results are discussed on the basis of the cellular kinetics of the haemopoietic cell system.     

射线和细胞抑制剂对胸腺和骨髓超微结构的影响

LACA50日龄小鼠,分别⁶⁰Coγ线8.25Gy一次全身照射,腹腔注射环磷酰胺(1.5mg/只)或地塞米松(0.1mg/只)后6、24和72小时活杀,光镜和电镜下观察并比较胸腺和骨髓的损伤特点.结果表明:辐射不仅损伤胸腺,同时严重地损伤骨髓的造血功能.环磷酰胺可能对胸腺和骨髓部有作用,但骨髓的损伤比胸腺严重的多.地塞米松选择性地损伤胸腺.推测对于严重再障病人移植骨髓之前的预处理方案中采用地塞米松代替环磷酰胺,可能收到较好的效果.     

全身垂直振动对去卵巢骨质疏松大鼠血清和骨组织碱性磷酸酶水平的影响

目的:观察全身垂直振动对去卵巢骨质疏松大鼠血清和骨组织碱性磷酸酶水平的影响。方法:将36只3月龄雌性SD大鼠按体重分层后随机分为假手术、去卵巢静止和去卵巢振动三组。去卵巢10周后,去卵巢振动组每天进行2次全身垂直振动治疗,振动频率90 Hz,时间15 min。治疗7周时,采用双能Χ线骨密度仪检测各组大鼠左侧离体股骨骨密度,用721分光光度计检测血清和右侧股骨远端碱性磷酸酶水平。结果:与假手术组比较,去卵巢静止组血清碱性磷酸酶水平显著增加,股骨远端碱性磷酸酶水平以及离体股骨近端和远端的骨密度显著下降,而离体股骨中段骨密度无显著变化。与去卵巢静止组比较,去卵巢振动组离体股骨远端碱性磷酸酶水平以及股骨近端和远端骨密度显著增加,而血清碱性磷酸酶水平和离体股骨中段骨密度无显著变化。结论:全身垂直振动可能通过增加骨组织碱性磷酸酶水平改善去卵巢骨质疏松大鼠的骨密度。     

Comparative Protection of Haemopoietic Colony-forming Cells and Lethally X-irradiated Mice by Mixtures of Radioprotectors

Summary

Mit 3,4-Benzpyren, Pyren und Berberinsulfat sensibilisierte Saccharomyces carlsbergensis-Zellen werden durch ultraviolette Strahlem im Bereich von 3000 bis 4000 Å in Wasser und auf Glas inaktiviert, während sie auf Agar-Agar und auf Gelatine—mit und ohne Nährstoffe—nur geringfügig geschädigt werden. Eine ausgeprägte Schädigung resultiert dann, wenn das Substrat—Agar, Gelatine—selbst den Sensibilisator enthält.     

Evaluation of 18F-FDG Uptake Pattern in Brown Adipose Tissue Over Extended Time Period as Assessed by Multiple Time Point 18F-FDG-PET

Purpose

To study the ¹⁸F-FDG uptake pattern in brown adipose tissue (BAT) over an extended time period, by multiple-time-point fluorodeoxyglucose positron emission tomography (FDG-PET) imaging. The primary objective for this kind of research was that it could form a basis and may have further implications for obesity research, metabolic diseases and for cachexia of both malignant and benign origin.

Methods

A total of 12 patients who had undergone routine FDG-PET for disease evaluation and had demonstrated prominent BAT uptake in their baseline scans were selected. The patients with the diagnosis of neuroendocrine tumors were excluded. Maximum standardized uptake values (SUVmax) were calculated in the BAT of the supraclavicular and paravertebral areas of either side, and were analyzed separately to examine their behavior individually. Time activity curves (TACs) were generated for [A] BAT SUVmax values and [B] SUVmax ratio of BAT/lung (B/L SUVmax ratio) at various time points.

Results

Ten out of the 12 patients were imaged at four time points, and two patients were imaged for two time points. Amongst a total of n = 30 sites, 23 were imaged at four time points and seven were imaged at two time points. Seventeen out of 30 area sites (56.67 %) demonstrated a peak value at 60 min and a falling trend of SUVmax afterwards; the remaining showed a peak uptake value between 85 and 300 min after the first scan (i.e. 145–360 min after injection), and falling values thereafter. With regard to the B/L SUVmax ratio, ten out of 30 sites (33.33 %) demonstrated peak uptake at 60 min, and the remaining showed a rise, with peak uptake at times between 85 and 300 min after the first scan (i.e. 145–360 min after injection) and falling values thereafter. No additional area of BAT uptake was observed over the extended time period in this study.

Conclusion

Wide variability was observed in the BAT FDG uptake over an extended period of time. Nearly half of the sites demonstrated an increase in FDG uptake until 360 min (i.e. 6 h) after injection, while the remaining half showed peak uptake at 1 h and subsequent fall of uptake. In the future, it will be worthwhile to study whether there exists any difference in time course of FDG uptake in brown fat between patients with cancer and those scanned for benign etiologies, or between obese and non-obese individuals.     

Analysis of immune cell populations and cytokine profiles in murine splenocytes exposed to whole-body low-dose irradiation

Purpose: In contrast to high-dose therapeutic irradiation, definitive research detailing the physiological effects of low-dose irradiation is limited. Notably, the immunological response elicited after low-dose irradiation remains controversial.

Materials and methods: Female C57BL/6 mice were whole- body-irradiated with a single or three daily fractions up to a total dose of 0.1, 1, or 10 cGy. Blood and spleen were harvested 2, 7 and 14 days after irradiation.

Results: The splenic CD4⁺ T cell subpopulations were temporarily increased at 2 days after single or fractionated irradiation, whereas the percentage of dendritic cells (DC) and macrophages was decreased. Whereas CD8⁺ T cell populations were decreased in single-dose irradiated mice at day 7, early and sustained reduction of CD8⁺ T cell numbers was observed in fractionated- dose-irradiated mice from day 2 until day 14. In addition, single-dose irradiation resulted in a Th1 cytokine expression profile, whereas fractionated-dose irradiation drove a Th2 shift. Additionally, increased expression of immune-related factors was observed at early time-points with single-dose irradiation, in contrast to the dose-independent induction following fractionated-dose irradiation.

Conclusions: Our results demonstrate that low-dose irradiation modulates the immune response in mice, where the sensitivity and kinetics of the induced response vary according to the dosing method.     

应用组织多普勒成像技术评价急性心肌梗死患者经皮冠状动脉腔内成形术疗效

目的 应用脉冲组织多普勒成像技术（DTI-PW）评估急性心肌梗死（AMI）患者经皮冠状动脉腔内成形术（PCI）术前术后左室心肌舒缩功能。方法 应用DTI-PW技术测量14例急性心肌梗死患者PCI术前、术后二尖瓣环、左室心肌各节段的收缩及舒张功能的指标，并与32例正常对照组比较。结果 AMI组术前室壁及二尖瓣环的S、E、SVTI、EVTI、ΔV、MVG明显低于正常组；E／A比值下降。术后左室心肌各节段及二尖瓣环S、E、SVTI、EVTI提高，△V及MVG无明显改善。结论 DTI技术可实时、准确地反映心肌舒缩运动状况，为进一步了解心肌功能提供更多信息。     

低强度激光照射对小鼠脑组织单胺类递质含量的影响

目的研究低强度激光照射对小鼠脑组织中单胺类神经递质含量的影响。方法将小鼠随机分为５组,每组１５只。其中３组麻醉下暴露颅骨后分别接受１３．８、２７．５、５５．０Ｊ／ｃｍ２的ＨｅＮｅ激光局部照射,分别称激光Ａ、Ｂ、Ｃ组;另２组分别为正常对照组和假照射组（只麻醉后暴露颅骨,不照射激光）。照射后断颈处死小鼠,取全脑。采用高效液相色谱电化学方法检测脑组织中多巴胺（ＤＡ）、５羟色胺（５ＨＴ）、去甲肾上腺素（ＮＥ）、高香草酸（ＨＶＡ）和５羟吲哚乙酸（５ＨＩＡＡ）含量。结果激光Ａ组脑组织ＤＡ、５ＨＴ含量高于正常对照组,ＤＡ高于假照射组;激光Ｂ组ＤＡ、５ＨＴ、ＮＥ含量高于正常对照组,ＤＡ和５ＨＴ含量高于假照射组;激光Ｃ组ＤＡ、５ＨＴ、ＮＥ均高于正常对照组和假照射组。以上差异均有显著意义（均为Ｐ＜０．０５）。假照射组与正常对照组比较,各项指标间差异均无显著意义（Ｐ＞０．０５）。结论低强度ＨｅＮｅ激光照射可使小鼠脑组织ＤＡ、５ＨＴ、ＮＥ含量增加。为激光治疗帕金森病提供了初步的实验依据     

Increase in efficacy of cancer radiotherapy by combination with whole-body low dose irradiation

Purpose:Design of cancer radiotherapy protocol to reduce radiation dose and increase treatment efficacy in Lewis lung cancer (LLC) model.

Methods: C57BL/6J mice subcutaneously implanted with LLC were treated by conventional radiotherapy (2Gy × 6) combined with LDWBI (low dose whole-body irradiation; the second, third, fifth and sixth local doses of 2Gy each substituted by LDWBI with 0.075Gy) and/or gene therapy (intratumor injection of pEgr-IL-18-B7.1 plasmid 24 h before the first and fourth local doses). Immunologic mechanisms were explored.

Results: Cancer control was most significantly improved in the group receiving local radiotherapy combined with LDWBI and gene therapy as shown by prolongation of mean survival time by 60.4%, reduction in average tumor weight by 70.8%, decrease in pulmonary metastasis by 66.9% and decrease in intratumor angiogenesis by 64.8% as compared to local radiotherapy alone (p < 0.05). These changes in tumor growth and progression were accompanied with up-regulation of host immunity manifested by stimulated NK (natural killer) and CTL (cytotoxic T lymphocyte) activity, IFN (interferon)-gamma and TNF (tumor necrosis factor)-alpha secretion, PKC (protein kinase C)-theta activation and LAMP (lysosomal associated membrane protein)-1 expression.

Conclusion: Combination of conventional radiotherapy with LDWBI and gene transfer could reduce total radiation dose by 2/3 and at the same time improve treatment efficacy of cancer accompanied with up-regulated host anticancer immunity.     

Differences in the Acute Intestinal Syndrome after Partial and Total Abdominal Irradiation in Mice

Summary

The acute intestinal syndrome in mice was analysed after partial (PAI) and total abdominal irradiation (TAI). The LD_50/15 was significantly higher after PAI (16·3 Gy) than after TAI (14·3 Gy). The dose—response curve for maximal weight loss also showed a shift of 1·8–2 Gy to higher doses after PAI compared with TAI. The X-ray survival curve for duodenal crypt cells was shifted by only 0·6 Gy for PAI and TAI. In order to assess the possible role of radiation-induced leucopenia and the influence of irradiating the spleen (shielded with PAI), lethality, weight loss and blood leucocyte counts were comapred after PAI and TAI in splenectomized and non-splenectomized mice. No major difference in leucopenia was found between the different treatment groups, whereas the differences in lethality and weight loss between PAI and TAI remained the same. Shielding the spleen in the partial abdominal field therefore did not contribute to the difference in LD_50/15. These findings imply that the increased LD_50/15 after PAI compared with TAI was mainly due to shielding of a small part of the bowel (about 13 per cent of the abdominal area).     

Analysis of Incidental Radiation Dose to Uninvolved Mediastinal/Supraclavicular Lymph Nodes in Patients with Limited-Stage Small Cell Lung Cancer Treated Without Elective Nodal Irradiation

Classic teaching states that treatment of limited-stage small cell lung cancer (L-SCLC) requires large treatment fields covering the entire mediastinum. However, a trend in modern thoracic radiotherapy is toward more conformal fields, employing positron emission tomography/computed tomography (PET/CT) scans to determine the gross tumor volume (GTV). This analysis evaluates the dosimetric results when using selective nodal irradiation (SNI) to treat a patient with L-SCLC, quantitatively comparing the results to standard Intergroup treatment fields. Sixteen consecutive patients with L-SCLC and central mediastinal disease who also underwent pretherapy PET/CT scans were studied in this analysis. For each patient, we created SNI treatment volumes, based on the PET/CT-based criteria for malignancy. We also created 2 ENI plans, the first without heterogeneity corrections, as per the Intergroup 0096 study (ENI_off) and the second with heterogeneity corrections while maintaining constant the number of MUs delivered between these latter 2 plans (ENI_on). Nodal stations were contoured using published guidelines, then placed into 4 “bins” (treated nodes, 1 echelon away, >1 echelon away within the mediastinum, contralateral hilar/supraclavicular). These were aggregated across the patients in the study. Dose to these nodal bins and to tumor/normal structures were compared among these plans using pairwise t-tests. The ENI_on plans demonstrated a statistically significant degradation in dose coverage compared with the ENI_off plans. ENI and SNI both created a dose gradient to the lymph nodes across the mediastinum. Overall, the gradient was larger for the SNI plans, although the maximum dose to the “1 echelon away” nodes was not statistically different. Coverage of the GTV and planning target volume (PTV) were improved with SNI, while simultaneously reducing esophageal and spinal cord dose though at the expense of modestly reduced dose to anatomically distant lymph nodes within the mediastinum. The ENI_on plans demonstrate that intergroup-style treatments, as actually delivered, had statistically reduced coverage to the mediastinum and tumor volumes than was reported. Furthermore, SNI leads to improved tumor coverage and reduced esophageal/spinal cord dose, which suggests the possibility of dose escalation using SNI.     

大隐静脉曲张腔内激光治疗后的并发症及其防治

目的 探讨大隐静脉曲张腔内激光治疗后的并发症及其防治.方法 对我院近3年来采用激光治疗的下肢静脉曲张316例的临床资料进行回顾性分析.结果 316例患者术后发生皮下淤血114例次;大隐静脉主干及小腿局部条索状硬结、红肿及严重疼痛17例次;隐神经损伤导致皮肤感觉异常89例次;皮肤灼伤29例次;溃疡合并感染1例,下肢深静脉血栓形成1例;经相应治疗后均痊愈.结论 大隐静脉曲张腔内激光治疗创伤较小、安全,但可发生并发症,应认真对待和处理.     

健脾增免中药对小鼠免疫机能及力竭性游泳运动能力的影响

目的 :观察健脾增免中药对小鼠免疫机能、血睾、血红蛋白、力竭性游泳运动能力的影响。方法 :采用3 H -TdR掺入法、ELISA法 ,12 5I-睾酮测定等。结果 :服用健脾增免中药 4周后 ,高剂量组 (ISSIH)IL-2水平显著高于其它各组 (P <0 0 0 1 ) ,脾细胞数明显高于对照组 (CON) (P <0 0 5 ) ,淋巴细胞对刀豆蛋白 (ConA)的增殖反应显著高于对照组 (P <0 0 1 )及阳性药物组 (PD) (P<0 0 5 ) ;中剂量组 (ISSIM)的淋巴细胞对脂多糖 (LPS)的增殖反应显著高于其它各组 (P <0 0 1 ) ;PD组血清睾酮 (T)显著高于其它各组 (P <0 0 0 1 ) ,ISSIH组T明显高于CON组 (P <0 0 5 )。该中药对体重 (W)、血红蛋白(Hb)无明显影响 ,但可明显延长小鼠力竭性游泳时间。毒性实验表明该药物安全无毒。结论 :健脾增免中药有增强机体免疫力、提高血清睾酮水平和抗疲劳的作用     

低强度激光照射对实验性牙齿移动牙周组织中P物质表达的影响

目的观察低强度He-Ne激光照射对大鼠实验性牙齿移动牙周组织中P物质表达的影响。方法将健康Wistar大鼠35只随机分为7组:未加力组及加力1、3、5、7、14和21d组,每组5只。分别在大鼠左右上颌切牙和第一磨牙间结扎镍钛闭合螺旋弹簧,约产生40g力。各组动物采用自身对照,右侧为低强度照射侧,左侧为对照侧。波长为632.8nm,输出功率为10mW的He-Ne激光照射上颌第一磨牙。处死大鼠,组织标本切片,免疫组织化学ABC染色,结合计算机图像分析测定各组P物质免疫阳性反应。结果低强度He-Ne激光照射侧牙周组织压力区在5d、7d组P物质免疫阳性反应明显高于对照侧;在14d组P物质免疫阳性反应仍较对照侧高。低强度He-Ne激光照射侧牙周组织张力区P物质免疫阳性反应在14d组较明显高于对照侧。结论低强度He-Ne激光照射对实验性牙齿移动牙周组织中P物质的表达有影响。     

The Formation of Peroxides in Tissue Lipids and Unsaturated Fatty Acids by Irradiation

Summary

Lipids extracted from rat liver, heart, brain, kidney and spleen have been shown to produce peroxides after irradiation with electrons. Peroxide formation was much greater in irradiated aqueous emulsions of lipids than in irradiated dry lipids, and it varied with the tissue used, a dose of 5 kilorads producing 5·0 × 10^?8 moles peroxide/mg heart lipid but only 0·36 × 10^?8 moles/mg spleen lipid.

Dilute emulsions formed considerably more peroxide than concentrated emulsions, and the peroxide yield depended on the emulsifying agent used, its concentration and the ph. Peroxide formation per gram tissue is similar to yields found in irradiated animals, and it is considered possible that peroxide formation in vivo may be a result of direct oxidation of unsaturated lipids by oxidizing radicals formed in the aqueous phase.     

Urinary Excretion of Cyclic Nucleotides,Creatinine Prostaglandin E2 and Thromboxane B2 from Mice Exposed to Whole-body Irradiation from an Enhanced Neutron Field

Summary

Urine volume and excretion of cyclic AMP, cyclic GMP, prostaglandin E₂ (PGE₂), thromboxane B₂ (TxB₂) and creatinine were evaluated as potential indicators of radiation damage in mice given 2–5 Gy to the whole body from an enhanced neutron field. In general, urinary cyclic AMP, cyclic GMP, creatinine and urine volumes were positively correlated across time postexposure, for each radiation dose. TxB₂ levels positively correlated with urine volume and cyclic AMP excretion only in animals given 2·0 Gy. None of these parameters suggests their use as a prognostic indicator of the extent of radiation damage. Urinary excretion of PGE₂ was negatively correlated with other urinary parameters. Biphasic increases in urinary PGE₂ were also observed. The initial transient elevation 2–3 days postexposure was not correlated with the dose (2–5 Gy). The second elevation of PGE₂ excretion occurred at 6–10 days. The magnitude of the latter increase suggests that urinary PGE₂ excretion may be a useful indicator of whole-body or kidney exposure to neutron fields.     

3D生物打印技术在组织工程支架构建与再生中的应用进展

具备个性化、精准化的3D生物打印技术构建优良生物相容性的组织工程支架,替换或修复人体中病变的组织和/或器官,在组织工程研究中极具广泛的应用前景。而作为3D打印技术的基材,如金属、生物陶瓷、高分子材料和细胞生物材料等,也因此得到了研究者的重视和研发。由金属和生物陶瓷制备的支架具有高强度和耐腐蚀性,已在骨科中得到广泛应用,而高分子材料由于其和细胞/组织的良好生物相容性及可塑性使其在软骨、矫形外科、心血管系统等组织/器官中被广泛研究。相信在不久的将来,以上述材料为基材结合3D生物打印技术构建的组织和器官,在临床上会得到应用和推广。本文就用于3D打印的生物材料及其打印技术在组织工程支架构建及组织再生中的应用进行综述。     

A Comparison between the Effects in Mice of Injected Organic Peroxides and of Whole-body X-irradiation

Summary

The toxic effects of whole-body x-irradiation and of intraperitoneally injected linoleic acid peroxide, disuccinoyl peroxide, dibenzoyl peroxide, 1 hydroxycyclohexyl hydroperoxide, tetralin hydroperoxide and tert.-butyl hydroperoxide have been studied in R♀ mice. There is no resemblance between the times of death after radiation and after peroxides. The latter act very rapidly, and most deaths occur in the first three days after treatment. Disuccinoyl peroxide and dibenzoyl peroxide differ from radiation in their effect on the growth-curves of animals surviving sub-lethal doses. Additive experiments, in which peroxides and radiation are given together, do not generally cause any marked augmentation of toxic effects by the two agents. A.E.T. protects successfully against radiation, but does not protect against any of the peroxides tested. Conversely, doses of ascorbic acid which protect against disuccinoyl peroxide do not protect against radiation. It is concluded that in those aspects studied there is little resemblance between radiation and injected peroxide.