Institutional (local) diagnostic reference levels in fluoroscopically guided spine surgery

In this study, institutional (local) diagnostic reference levels (LDRLs) and action levels (ALs) for spine interventional procedures are reported. Fluoroscopy time (FT), kerma area product (KAP), cumulative dose (CD), as well as anatomical, clinical and technical factors affecting procedure complexity were recorded for 156 patients who underwent cervical and thoraco-lumbar interventions. Patient entrance surface dose (ESD), effective dose (ED), thyroid absorbed dose and gonadal dose were also estimated, based on KAP measurements. The LDRLs and ALs were calculated as the 75th and 10th percentile of FT, KAP and CD values for the total group of patients, as well as utilizing the weight banding method and the size correction method. For the total distribution of patients, the LDRLs for cervical and thoraco-lumbar interventions are 0.15 min and 0.29 min for FT values, 0.10 Gy cm² and 0.71 Gy cm² for KAP values, as well as 0.47 mGy and 3.24 mGy for CD values, respectively. The corresponding ALs are 0.03 min and 0.03 min, 0.01 Gy cm² and 0.07 Gy cm², as well as 0.05 mGy and 0.33 mGy for FT, KAP and CD values, respectively. The age and treated levels had a significant influence on the reference dose values only for cervical interventions, whereas none of the other included factors showed statistically significant association for both cervical and thoraco-lumbar interventions. The weight banding method resulted to reference values comparable to those obtained for the whole group of patients, while the size correction method resulted to lower values. The mean ESD values were 1.58 mGy (range 0.02–13.58 mGy) for cervical and 23 mGy (range 0.004–390.3 mGy) for thoraco-lumbar interventions. The corresponding mean ED values were 0.012 mSv (range 0.001–0.097 mSv) and 0.124 mSv (range 0.00002–2.11 mSv), respectively. The mean thyroid and gonadal doses were 0.14 mGy (range 0.002–1.12 mGy) and 0.044 mGy (range 0.000003–1.56 mGy), respectively. The LDRLs and ALs reported could contribute in the effort for establishing national DRLs and for increasing neurosurgeons awareness regarding patient dose and radiation protection issues during spine interventional procedures.     

Proposal of a flow scheme for the chemical-form-based quantitative analysis of chlorine compounds in pulp for sanitary products and verification of safety

To determine the amounts and chemical forms of chlorine compounds in elemental chlorine-free (ECF) bleached pulp for sanitary products, a chemical-form-based quantitative analysis flow scheme was created. The scheme involves quantitative determination of compounds eluted in elution tests assuming dermal exposure. The results indicated that most of the chlorine compounds in pulp used for sanitary products were insoluble organically bound chlorine and water-soluble chlorides consisting of chloride ions. The total amount of chlorine obtained by analysis of the total chlorine in the pulp products was close to the sum of the amounts of water-soluble chlorides, residual chlorine, chloroacetic acids, and insoluble organically bound chlorine. Therefore, the balance of chlorine measured by the flow scheme was acceptable. Little residual chlorine was detected in the pulp products, suggesting that the chlorine dioxide used for bleaching was almost completely converted into inactive inorganic chlorides and organic chlorine compounds and that these substances do not affect the health risk posed by pulp products. A risk assessment of the detected chloroacetic acid and dichloroacetic acid revealed that there is no concern about the health risk posed by use of these products.     

RNA interference and dietary inhibitors induce a similar compensation response in Tribolium castaneum larvae

Tribolium castaneum is a major agriculture pest damaging stored grains and cereal products. The T. castaneum genome contains 26 cysteine peptidase genes, mostly cathepsins L and B, and seven have a major role in digestion. We targeted the expression of the most highly expressed cathepsin L gene on chromosome 10, TC011001, by RNA interference (RNAi), using double‐stranded RNA (dsRNA) constructs of different regions of the gene (3′, middle, 5′ and entire coding regions). RNA sequencing and quantitation (RNA‐seq) was used to evaluate knockdown and specificity amongst the treatments. Overall, target gene expression decreased in all treatment groups, but was more severe and specific in dsRNA targeting the 3′ and entire coding regions, encoding the proteolytic active site in the enzyme. Additional cysteine cathepsin genes also were down‐regulated (off‐target effects), but some were up‐regulated in response to RNAi treatment. Notably, some serine peptidase genes were increased in expression, especially in dsRNA targeting 5′ and middle regions, and the response was similar to the effects of dietary cysteine protease inhibitors. We manually annotated these serine peptidase genes to gain insight into function and relevance to the RNAi study. The data indicate that T. castaneum larvae compensate for the loss of digestive peptidase activity in the larval gut, regardless of the mechanism of disruption.     

用于阴道黏膜消毒产品的毒理学安全性评价

目的了解用于阴道黏膜消毒产品的毒性,以评价其使用安全性。方法采用动物试验方法,对41种用于黏膜消毒产品的毒性进行了评价。结果主要成分为碘伏类、醋酸洗必泰、季铵盐类、中草药和其他类的41个消毒产品,在急性经口毒性试验观察期内,均未发现试验动物有明显中毒反应,试验动物解剖未发现组织和脏器有异常病变。所试验的41种用于黏膜消毒的产品小鼠急性经口LD50均>5000 mg/kg体重,属实际无毒级。阴道黏膜刺激试验,碘伏类产品通过率为86.7%;醋酸氯己定类产品通过率为72.7%;季铵盐类产品通过率为83.3%;含中草药的产品通过率为80.0%;其他类产品通过率为75.0%。结论大部分用于阴道黏膜的产品属实际无毒级,较为安全。     

Ultrasensitive determination of melamine in milk products and biological fluids by luminol-hydrogen peroxide chemiluminescence

An ultrasensitive chemiluminescence (CL) method for determination of melamine at picogram level was reported in a flow system. It was found that melamine can accelerate the electrons transferring rate of excited 3-aminophthalate with notable enhanced CL intensity of luminol-hydrogen peroxide reaction. The increased CL intensity was proportional to the concentration of melamine in the range from 2.5 to 250 pg mL⁻¹ (R² = 0.9953), with a detection limit of 0.9 pg mL⁻¹ (3σ) and the relative standard deviations lower than 5.0%. The proposed method was successfully applied to determine the melamine in liquid milk, yogurt, human urine and serum samples with the recovery of 98–105%, 93–105%, 98–105%, 97–109%, respectively.     

自觉听力正常耳鸣患者纯音听力及畸变产物耳声发射临床分析

目的分析自觉听力正常耳鸣患者的纯音听力特征,并探讨自觉听力正常耳鸣患者畸变产物耳声发射(distortion product otoacoustic emission,DPOAE)测定值与纯音听阈值之间的相关性及其意义。方法 2010—2011年在我科就诊的以耳鸣为第一主诉但无明显自觉听力障碍患者114例(190耳),对所有入组患者进行纯音测听及DPOAE检测。分析DPOAE测定值与纯音听阈值之间的相关性,并结合其发病的可能危险因素进行相关分析。结果自觉听力正常的耳鸣患者中,听力异常可达76.84%(146/190)。纯音测听表现为:高频下降型46.31%(88/190);低频下降型14.73%(28/190);正常23.15%(44/190);其它类型15.78%(30/190)。其危险因素主要为:噪声接触,疲劳和/或精神压力、其他基础疾病等。所有频率(f0)的DPOAE幅值与各频率纯音听阈间存在负相关,且有明显的频率对应关系。结论自觉听力正常的耳鸣患者存在一定程度的听力损失,尤其以高频听力下降为多见。DPOAE测定值与其纯音听阈之间呈明显的负相关关系,且DPOAE测试频率与纯音听阈频率间存在明显的对应关系,DPOAE检测作为一种客观指标,可以在一定程度上反映自觉听力正常耳鸣患者的听力损失程度,有一定的临床应用价值。     

Complete synchronization of temporal Boolean networks

This letter studies complete synchronization of two temporal Boolean networks coupled in the drive-response configuration. Necessary and sufficient conditions are provided based on the algebraic representation of Boolean networks. Moreover, the upper bound to check the criterion is given. Finally, an illustrative example shows the efficiency of the proposed results.     

Neuroprotection of N-benzylcinnamide on scopolamine-induced cholinergic dysfunction in human SH-SY5Y neuroblastoma cells

Alzheimer's disease, a progressive neurodegenerative disease, affects learning and memory resulting from cholinergic dysfunction. Scopolamine has been employed to induce Alzheimer's disease-like pathology in vivo and in vitro through alteration of cholinergic system. N-benzylcinnamide(PT-3), purified from Piper submultinerve, has been shown to exhibit neuroprotective properties against amyloid-β-induced neuronal toxicity in rat cortical primary cell culture and to improve spatial learning and memory of aged rats through alleviating oxidative stress. We proposed a hypothesis that PT3 has a neuroprotective effect against scopolamine-induced cholinergic dysfunction. PT-3(125–200 n M) pretreatment was performed in human neuroblastoma SH-SY5 Y cell line following scopolamine induction. PT-3(125–200 n M) inhibited scopolamine(2 m M)-induced generation of reactive oxygen species, cellular apoptosis, upregulation of acetylcholinesterase activity, downregulation of choline acetyltransferase level, and activation of p38 and JNK signalling pathways. These findings revealed the underlying mechanisms of scopolamine-induced Alzheimer's disease-like cellular dysfunctions, which provide evidence for developing drugs for the treatment of this debilitating disease.