Quality assurance of a helical tomotherapy machine

Helical tomotherapy has been developed at the University of Wisconsin, and 'Hi-Art II' clinical machines are now commercially manufactured. At the core of each machine lies a ring-gantry-mounted short linear accelerator which generates x-rays that are collimated into a fan beam of intensity-modulated radiation by a binary multileaf, the modulation being variable with gantry angle. Patients are treated lying on a couch which is translated continuously through the bore of the machine as the gantry rotates. Highly conformal dose-distributions can be delivered using this technique, which is the therapy equivalent of spiral computed tomography. The approach requires synchrony of gantry rotation, couch translation, accelerator pulsing and the opening and closing of the leaves of the binary multileaf collimator used to modulate the radiation beam. In the course of clinically implementing helical tomotherapy, we have developed a quality assurance (QA) system for our machine. The system is analogous to that recommended for conventional clinical linear accelerator QA by AAPM Task Group 40 but contains some novel components, reflecting differences between the Hi-Art devices and conventional clinical accelerators. Here the design and dosimetric characteristics of Hi-Art machines are summarized and the QA system is set out along with experimental details of its implementation. Connections between this machine-based QA work, pre-treatment patient-specific delivery QA and fraction-by-fraction dose verification are discussed.     

Flow cytometric analysis of procalcitonin expression in human monocytes and granulocytes

Fluorescent monoclonal antibody labelling followed by a lysed whole blood method and flow cytometry was used to determine the lymphocyte subpopulations in 127 (64 males and 63 females) normal healthy individuals in the adult (age 18-59 years) Kuwaiti population. Relative percentages and absolute values of CD2+, CD3+, CD19+, CD4+, CD8+, HLADR+, CD56+, CD45RO+, and CD45RA+ cells were determined. The reference ranges were CD2+, 73-92% (0.95-2.99 x 10(9) per l), CD3+, 64-85% (0.83-2.71 x 10(9) per l), CD19+, 6-22% (0.05-0.61 x 10(9) per l), CD4+, 34-54% (0.45-1.65 x 10(9) per l), CD8+, 20-42% (0.29-1.17 x 10(9) per l), HLADR+, 4-23% (0.02-0.62 x 10(9) per l), CD56+, 4-22% (0.06-0.58 x 10(9) per l), CD45RO+, 16-53% (0.26-1.42 x 10(9) per l) and CD45RA+, 35-72% (0.34-2.05 x 10(9) per l). The mean CD4/CD8 ratio was 1.50+/-0.35. CD3+ cells were positively correlated to both CD4+ and CD8+ cells (P<0.001), and CD4+ cells showed a significant positive correlation with CD8+ cells (P<0.001).     

应用四唑盐比色法对5种骨水泥的细胞毒性的测试

0　引言　应用细胞培养法对牙科材料的生物相容性进行评价是一种简便、有效、经济的方法 .近年来 ,国内外有许多学者报道用 MTT检测细胞活性 ,并认为用 MTT法可以代替活细胞计数、同位素标记进行细胞毒性试验 .我们应用 MTT法对 5种骨水泥的细胞毒性进行了评价 ,并对有关问题进行了讨论 .1　材料和方法1.1　测试材料　 1号 :生物水泥 ,2号 :羟基磷灰石人工骨 ,3号 :氰基丙烯酸酯骨水泥 1号 (自制 ) ,4号 :氰基丙烯酸酯骨水泥 2号 (自制 ) ,5号 :氰基丙烯酸酯骨水泥 3号 (自制 ) .阴性对照采用珊瑚 ,阳性对照采用聚氯乙烯 .1.2　实验步骤…     

Patient controlled analgesia: evaluation of pain management and patient outcome

A study was conducted to evaluate patient response to patient controlled analgesia (PCA) devices. All patients were interviewed for this concurrent study. A survey was also taken with the nursing staff for their assessments regarding PCA therapy and comparison of outcomes between morphine and meperidine use. Our goal was to see what improvements could be made in pain management and patient therapy wherever possible.     

陵水暗罗活性成分研究

从陵水暗罗(polyalthia nemoralis A.etDC)根的乙醇提取物中分离得到五个化合物。经光谱(UV,IR,¹H-NMR,¹³C-NMR,DEPT和MS)解析和化学反应,分别鉴定为暗罗素(zincpolyanemine,PN1),2-巯基吡啶-N-氧化物铜盐(PN₂),β-谷甾醇(PN₃),β-谷甾醇-β-D-吡喃葡萄糖甙(PN₄)和2-巯基吡啶-N-氧化物-2-S-β-D-吡喃葡萄糖甙(PN₅),其中PN₅为新化合物,PN2为新天然产物。PN1和PN2有较强抗疟、防霉杀菌作用。PN5的抗疟、防霉试验尚在进行中。     

Alterations of the thrombin generation profile in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder resulting in the erosion of the cartilage and bone. Systemic involvement including the cardiovascular system with the risk of atherosclerosis may also occur. Calibrated automated thrombogram (CAT), a commercially available thrombin generation assay is suitable for the general assessment of the functionality of coagulation system. In this study we performed CAT assay in RA patients and in non-affected control subjects (matched for age, sex and comorbidities). Among the CAT parameters Velocity Index increased (from 60 to 83 nM/min), Lag Time and Time to Peak decreased (from 3.47 to 2.83 min and from 6.98 to 5.58 min respectively) in RA. On the other hand, Endogenous Thrombin Potential values decreased (from 1242 to 1108 nM min). The observed alterations were not associated with the applied therapy. These results indicate that the velocity of thrombin formation is increased, while the thrombin generating capability is reduced in RA.     

Four categories of gamma-globin gene triplications: DNA sequence comparison of low G gamma and high G gamma triplications

The human fetal gamma chains are produced by closely linked G gamma and A gamma genes, and unequal crossing over between them leads to gamma gene deletions and triplications. Nine gamma gene triplications from seven ethnic groups were analyzed for G gamma and hemoglobin F (Hb F) values of heterozygotes and for the presence of polymorphic XmnI restriction sites 5' to the gamma genes. Four categories of triplication were found: I had low G gamma and low Hb F values and lacked XmnI sites 5' to the three gamma genes [---]. II had high G gamma and slightly elevated Hb F values but was also [---]. III was similar to II, except that XmnI was [+--]. IV had very high G gamma and slightly elevated Hb F values, and XmnI was [++-]. One case each of triplications I and IV were cloned into Charon 35. For both, the two 5' gamma gene code for G gamma chain, while the 3' gamma gene codes for A gamma chain. DNA sequencing showed that the unequal crossover occurred between 472 and 398 base pairs (bp) 5' to the gamma gene Cap sites (- 472 and -398) for the type IV triplication and between -271 and codon 136 for the type I triplication. In addition, type I had a 4-bp deletion of AGCA from -225 to -222. The high G gamma values of the type IV triplication are explained by its -G gamma-G gamma-A gamma-gene arrangement and the XmnI sites 5' to the G gamma genes. We hypothesize that the low G gamma value of the type I triplication, which is also -G gamma-G gamma-A gamma-, is due to inactivation of the middle G gamma gene by the AGCA deletion at -225 to -222.     

Met-enkephalin modulates lipid peroxidation and total sialic acid level in CBA mice in age- and sex-dependent manners

Age- and sex-associated differences in lipid peroxidation (LPO), and total sialic acid content (TSA) in response to abuse of drugs have been reported both in humans and experimental animals. However, no data on the influence of gender and age on these parameters have been reported for methionine-enkephalin (MENK). In this study we examined the influence of age and gender on MENK-induced LPO levels in the liver and TSA content in splenocytes of CBA mice. LPO production, which was age- and gender-associated was differentially regulated by MENK at a dose of 10 mg or 2.5 mg/kg body weight. At the higher dose, MENK stimulated LPO production in younger males and females but suppressed only in older male mice. At the lower dose, MENK induced strong suppression in males while being without any effect in females. In TSA levels, the age-associated increase was greater in males and much lower in females, with higher TSA levels in younger (2.5, 4.5 months) and decreased levels in older female mice (9 months) being observed. Contrary to the effect on LPO level, TSA level in MENK-treated mice was suppressed in both sexes but only in young 2.5-month-old mice. These data provide evidence that some immunomodulatory properties of MENK are age- and gender-associated which may be relevant to the potential use of MENK as adjuvant therapy in patients with immunocompromised status.