Electromagnetic navigation bronchoscopy‐guided fine needle aspiration for the diagnosis of lung lesions

Many peripheral lung lesions are beyond the reach of conventional bronchoscopes, and require percutaneous CT‐guided or open surgical biopsy, which carry increased risks to the patient. Electromagnetic navigation bronchoscopy (ENB) is a relatively new technique, which uses an image guided localization system to direct steerable bronchoscopic tools to predetermined points within the bronchial tree. This technology allows improved access to peripheral lesions in particular. We investigated the sensitivity and specificity of ENB‐guided fine needle aspiration (FNA) in the diagnosis of lung lesions. All ENB‐guided FNAs performed at one institution were included in the study. The superDimension i‐Logic System? was used in all cases. Pathologic reports of the ENB‐guided FNAs, as well as all other pulmonary sampling performed simultaneously with the FNA and within 1 year of the ENB‐guided FNA were reviewed. Patients with a positive ENB‐guided FNA or malignancy within the same lobe within the follow‐up period were considered positive for malignancy. Patients with an atypical diagnosis but no definitive malignancy were considered negative for malignancy for statistical purposes. Ninety‐one patients underwent 95 ENB‐guided FNAs over a 3‐year period. Thirty‐five patients (38%) were positive for malignancy. ENB‐guided FNA had a sensitivity of 63% for the detection of malignancy. The sensitivity for the detection of malignancy using all ENB‐guided sampling methods, including FNA, bronchoscopic biopsy, and bronchial brushing was 83%. Pathologists and cytotechnologists should be aware of ENB‐guided FNA as an emerging technology with a relatively high sensitivity for the diagnosis of peripheral lung lesions. Diagn. Cytopathol. 2014;42:1045–1050. © 2014 Wiley Periodicals, Inc.     

Effect of pulsed electromagnetic fields on calcium tissue changes in focal ischaemia

The effect of a pulsed electromagnetic field (PEMF) (parameters: 27.1 MHz, 585 W peak power, and 65 μs pulses, 400 times per second) on rats undergoing middle cerebral artery occlusion (MCAo) was investigated. Four groups of eight rats each underwent microsurgical MCAo. Two groups were treated with a PEMF generator for 2 h following the onset of ischaemia and were sacrificed at 4 and 24 h following the MCAo respectively. The other two groups were also sacrificed at the same time intervals. Regional brain sodium, potassium, and calcium tissue contents were determined by atomic spectrophotometry. As distinct from results found in spinal cord contusion, no significant difference between the PEMF-treated groups and the nontreatment groups was found. PEMF treatment did not alter the 300% rise in calcium tissue dry weight content observed at 24 h following MCAo in the infarcted tissue. Regional brain water content was determined by the dry weight method. A regionally inconsistent reduction in brain water content was noted in the PEMF-treated rats.     

Electromagnetic fields and the blood-brain barrier

The mammalian blood-brain barrier (BBB) consists of endothelial cells, linked by tight junctions, and the adjoining pericytes and extracellular matrix. It helps maintain a highly stable extracellular environment necessary for accurate synaptic transmission and protects nervous tissue from injury. An increase in its normally low permeability for hydrophilic and charged molecules could potentially be detrimental. Methods to assess the permeability of the BBB include histological staining for marker molecules in brain sections and measurement of the concentration of marker molecules in blood and brain tissue. Their advantages and disadvantages are discussed. Exposure to levels of radiofrequency electromagnetic fields (EMF) that increase brain temperature by more than 1 °C can reversibly increase the permeability of the BBB for macromolecules. The balance of experimental evidence does not support an effect of ‘non-thermal’ radiofrequency fields with microwave and mobile phone frequencies on BBB permeability. Evidence for an effect of the EMF generated by magnetic resonance imaging on permeability is conflicting and conclusions are hampered by potential confounders and simultaneous exposure to different types and frequencies of EMF. The literature on effects of low frequency EMF, which do not cause tissue heating, is sparse and does not yet permit any conclusions on permeability changes. Studies on the potential effect of EMF exposure on permeability of the BBB in humans are virtually absent. Future permeability studies should focus on low frequency effects and effects in humans. Care should be taken to avoid the methodological limitations of earlier studies and to determine the pathophysiological relevance of any changes found.     

恒古骨伤愈合剂联合特定电磁波治疗气滞血瘀型膝骨关节炎的多维度疗效分析

目的 多维度评估恒古骨伤愈合剂联合特定电磁波（TDP）治疗气滞血瘀型膝骨关节炎的临床疗效。方法 选取2019年7月至2021年12月于新疆维吾尔自治区第三人民医院诊治的接受保守治疗的104例气滞血瘀型膝骨关节炎患者，按照随机数表法随机分为对照组和观察组，各52例。对照组患者给予TDP治疗，观察组在对照组的基础上给予恒古骨伤愈合剂，两组患者均治疗1周，随访1月，多维度评估两组患者临床疗效。分别于治疗前和治疗后，从主观指标视觉模拟量表（VAS）评分、西安大略和麦克马斯特大学骨关节炎调查量表（WOMAC）评分，客观指标可视化压痛指数、可视化膝关节活动度分别对患者的疼痛和功能进行评估，并测定中医证候积分、测定血清红细胞沉降率（ESR）及高敏C反应蛋白（hs-CRP），综合评定临床总有效率。结果 两组患者基线特征及治疗前各项评分差异均无统计学意义。与本组治疗前比较，两组患者治疗后VAS评分、WOMAC评分、压痛指数、关节活动度、中医证候积分均有显著改善（P<0.01）。与对照组治疗后比较，观察组VAS评分、WOMAC评分显著降低（P<0.01）；观察组压痛指数改善程度优于对照组，差异有统计学意义（P<0.05），观察组关节活动度优于对照组，但差异无统计学意义；观察组中医证候积分显著降低（P<0.01）。治疗后两组患者ESR及hs-CRP水平均显著降低，且观察组低于对照组（P<0.01）。临床疗效方面，观察组总有效率为90.4%（47/52），明显高于对照组的53.8%（28/52），差异有统计学意义（P<0.05）。两组治疗期间均未见明显不良反应。结论 恒古骨伤愈合剂联合TDP治疗气滞血瘀型膝骨关节炎的临床疗效显著，从主客观两方面均可改善膝关节疼痛和功能，并可改善中医证候量化指标，降低炎症反应，安全性高。     

Speaker‐specific kinematic properties of alveolar reductions in English and German

A simultaneous EPG/EMA study of tongue gestures of five speakers was conducted to investigate the kinematic events accompanying alveolar stop reductions in the context of a velar plosive /k/ and in the context of a laryngeal fricative /h/ in two languages, English and German. No systematic language differences could be detected. Alveolar productions before a following /h/ showed only a marginal weakening of the formation of complete occlusion, while alveolar productions before a following /k/ showed a wide range of reductions, including instances of a complete deletion of the alveolar gesture. The extension of movement reduction varied between and within subjects. Importantly, while speakers were consistent with themselves, they employed different articulatory patterns with respect to the timing relationship between movement initiation, overall movement duration, peak velocity as well as closure duration. An attempt is made to relate the observed movement patterns to the dynamic factors of the speech mechanism.     

On the optimal choice of the exposure conditions and the nanoparticle features in magnetic nanoparticle hyperthermia

Purpose: Two points are particularly relevant for the clinical use of magnetic nanoparticle hyperthermia: the optimisation of both the exposure conditions and the magnetic nanoparticle characteristics, and the assessment of the limits of scalability of the treatment. To answer these two points a criterion for the individuation of the magnetic field parameters and of the magnetic nanoparticle features that minimise the therapeutic concentration of nanoparticles to be used in magnetic nanoparticle hyperthermia is developed.

Methods: The proposed criterion is based on the estimation of the levels of heat generation rate, due to the electromagnetic field, to be supplied to both the cancerous and the neighbouring healthy tissues for achieving the therapeutic heating of the tumour with a desired degree of spatial selectivity. These quantities are determined by exploiting the Pennes bioheat transfer model.

Results: The reliability of the criterion has been proven by means of an extensive numerical analysis, performed by considering tumours of spherical shape embedded in tissues of cylindrical shape. Several cases, including tumours of different sizes and position have been considered.

Conclusions: By exploiting the proposed criterion a study of the clinical scalability of the therapeutic approach is presented.