Psychophysiological tests and provocation of subjects with mobile phone related symptoms

The aim of the present study was to investigate the effect of exposure to a mobile phone-like radiofrequency (RF) electromagnetic field on persons experiencing subjective symptoms when using mobile phones (MP). Twenty subjects with MP-related symptoms were recruited and matched with 20 controls without MP-related symptoms. Each subject participated in two experimental sessions, one with true exposure and one with sham exposure, in random order. In the true exposure condition, the test subjects were exposed for 30 min to an RF field generating a maximum SAR(1g) in the head of 1 W/kg through an indoor base station antenna attached to a 900 MHz GSM MP. The following physiological and cognitive parameters were measured during the experiment: heart rate and heart rate variability (HRV), respiration, local blood flow, electrodermal activity, critical flicker fusion threshold (CFFT), short-term memory, and reaction time. No significant differences related to RF exposure conditions were detected. Also no differences in baseline data were found between subject groups, except for the reaction time, which was significantly longer among the cases than among the controls the first time the test was performed. This difference disappeared when the test was repeated. However, the cases differed significantly from the controls with respect to HRV as measured in the frequency domain. The cases displayed a shift in low/high frequency ratio towards a sympathetic dominance in the autonomous nervous system during the CFFT and memory tests, regardless of exposure condition. This might be interpreted as a sign of differences in the autonomous nervous system regulation between persons with MP related subjective symptoms and persons with no such symptoms.     

非剥脱性嫩肤技术在皮肤光老化中的应用

目的：介绍国内外近10年来非剥脱性嫩肤技术治疗皮肤光老化临床研究概况,以期进一步了解非剥脱性嫩肤技术在皮肤光老化中的应用新进展。方法：应用计算机检索Pubmed和中国生物医学文献数据库1999／2009的相关文章,限定文章语言种类为英文和中文,检索词“photoaging（光老化）,laser（激光）,Intense pulsed light（强光）,radiofrequency（射频）,Light Emitting Diode（发光二极管）”。对资料进行初审,选择临床实验研究文献查找全文。纳入标准：①有明确诊断标准。②随机对照实验或对照实验。结果：共收集到相关文献110篇,按上述标准纳入23篇,其余文献均被排除。结论：非剥脱性嫩肤技术治疗皮肤光老化疗效可靠,具有副作用少,方法简单,安全性高,易被患者接受等优势。但不管单独使用哪种方法治疗皮肤光老化其效果均不是很完美,必需紧密结合患者疾病的具体情况和非剥脱性嫩肤设备的性能进行个性化的治疗。     

超声引导下肝内胆管置管治疗肝内胆管结石并发梗阻的临床效果观察

目的:探究超声引导下肝内胆管置管治疗肝内胆管结石并发梗阻的临床效果和安全性。方法:选择2014年1月至2018年1月于我院接受治疗的98例肝内胆管结石并发梗阻患者为研究对象,将患者按照入院顺序统一编号后,根据随机数字表法进行分为实验组与对照组,每组各49例患者。对照组患者于常规X线引导下行肝内胆管置管治疗,实验组患者在超声引导下实施肝内胆管置管治疗,对比两组患者穿刺次数、手术时间、术后并发症的发生情况,并对两组患者随访3个月,比较其结石残余率及治疗效果。结果:(1)实验组患者穿刺次数及操作时间均显著少于对照组(P0.05);(2)实验组患者术后各类并发症发生率为4.08%,明显低于对照组(20.41%,P0.05);(3)对照组患者后3个月的结石残余率为14.29%(7/49),实验组为2.04%(1/49),显著低于对照组(P0.05);(4)术后3个月,实验组患者治疗总有效率为97.96%,明显高于对照组(81.63%,P0.05)。结论:与常规X线引导下行肝内胆管置管治疗相比,超声引导下肝内胆管置管在治疗肝内胆管结石并发梗阻中具有较更好的治疗效果和安全性。     

Effect of long-term exposure of 2.4 GHz radiofrequency radiation emitted from Wi-Fi equipment on testes functions

Abstract

The aim of this study was to investigate long-term effects of radiofrequency radiation (RFR) emitted from a Wireless Fidelity (Wi-Fi) system on testes. The study was carried out on 16 Wistar Albino adult male rats by dividing them into two groups such as sham (n: 8) and exposure (n: 8). Rats in the exposure group were exposed to 2.4?GHz RFR radiation for 24?h/d during 12 months (1 year). The same procedure was applied to the rats in the sham control group except the Wi-Fi system was turned off. Immediately after the last exposure, rats were sacrificed and reproductive organs were removed. Motility (%), concentration (×10⁶/mL), tail defects (%), head defects (%) and total morphologic defects (%) of sperms and weight of testes (g), left epididymis (g), prostate (g), seminal vesicles (g) were determined. Seminiferous tubules diameter (μm) and tunica albuginea thickness (μm) were also measured. However, the results were evaluated by using Johnsen’s score. Head defects increased in the exposure group (p?<?0.05) while weight of the epididymis and seminal vesicles, seminiferous tubules diameter and tunica albuginea thickness were decreased in the exposure group (p?<?0.01, p?<?0.001, p?<?0.0001). However, other alterations of other parameters were not found significant (p?>?0.05). In conclusion, we observed that long-term exposure of 2.4?GHz RF emitted from Wi-Fi (2420?μW/kg, 1?g average) affects some of the reproductive parameters of male rats. We suggest Wi-Fi users to avoid long-term exposure of RF emissions from Wi-Fi equipment.     

SAR versus VAR, and the size and shape that provide the most appropriate RF exposure metric in the range of 0.5-6 GHz

Basic restrictions for protecting against localized tissue heating induced from exposure to radiofrequency (RF) fields are typically specified as the specific energy absorption rate (SAR), which is mass averaged in recognition of the thermal diffusion properties of tissues. This article seeks to determine the most appropriate averaging mass (1, 3, 5, 7, or 10 g) and averaging shape (cube or sphere). We also consider an alternative metric, volumetric energy absorption rate (VAR), which uses volume averaging (over 1, 3, 5, 7, and 10 cm³; cube and sphere). The SAR and VAR averaging approaches were compared by considering which was a better predictor of tissue temperature rise (ΔT) induced by near‐ and far‐field RF exposures (0.5–6 GHz), calculated in a detailed human body model. For the exposure scenarios that we examined, VAR is better correlated with ΔT than SAR, though not at a statistically significant level for most of the metric types we studied. However, as VAR offers substantive advantages in ease of assessment we recommend this metric over SAR. Averaging over a cube or a sphere provides equivalent levels of correlation with ΔT, and so we recommend choosing the averaging shape on the basis of which is easier to assess. The optimal averaging volume is 10 cm³ for VAR, and the optimal mass is 10 g for SAR. The correlation between VAR or SAR and ΔT diminishes substantially at 6 GHz, where incident power flux density may be a better exposure metric. Bioelectromagnetics 32:312–321, 2011. © 2010 Wiley‐Liss, Inc.     

Cognitive effects of cellular phones: a possible role of non-radiofrequency radiation factors

Some studies found that cognitive functions of human beings may be altered while exposed to radiofrequency radiation (RFR) emitted by cellular phones. In two recent studies, we have found that experiment duration and exposure side (i.e., phone's location--right or left) may have a major influence on the detection of such effects. In this brief follow-up experiment, 29 right-handed male subjects were divided into two groups. Each subject had two standard cellular phones attached to both sides of his head. The subjects performed a spatial working memory task that required either a left-hand or a right-hand response under one of the two exposure conditions: left side of the head or right side. Contrary to our previous studies, in this work external antennas located far away from the subjects were connected to the cellular phones. This setup prevents any emission of RFR from the internal antenna, thus drastically reducing RFR exposure. Despite that, the results remain similar to those obtained in our previous work. These results indicate that some of the effects previously attributed to RFR can be the result of some confounders.     

Influence of traffic variations on exposure to wireless signals in realistic environments

In this article, the general public daily exposure to broadcast signals and Global System for Mobile Communications (GSM) or Universal Mobile Telecommunications System (UMTS) mobile telephone signals in indoor areas is investigated. Temporal variations and traffic distributions during a day at different indoor sites in urban and rural zones are presented. The goal is to analyze the real exposure compared to the maximum assessment imposed by radio protection standards and to characterize the ratio between daily and maximum theoretical values. Hence, a realistic maximum is proposed based on the statistical analysis performed using measurements. Broadcast signals remain constant over the day so they are best fitted with a Normal distribution while the mobile telephone signals depend on the traffic demand during the day so they fit a three‐Gaussian distribution model. A general mask is also constructed for underlining the maximum equivalent active traffic for different periods in the day. Also, relations between the mean values over 24 h, the realistic maximal values (at 99%) and the maximal theoretical values are presented. The realistic maximum is also presented with a sliding time average of 6 min applied to the measurements in accordance with international standards. An extrapolation factor is given for the different systems to easily assess the maximum values starting from an instantaneous measurement. The extrapolation factor is also given for a broadband measurement to estimate the maximum potential exposure during the day. Bioelectromagnetics 33:288–297, 2012. © 2011 Wiley Periodicals, Inc.     

Quantitative Determination of Site-Specific Conformational Distributions in an Unfolded Protein by Solid-State Nuclear Magnetic Resonance

Solid-state nuclear magnetic resonance (NMR) techniques are used to investigate the structure of the 35-residue villin headpiece subdomain (HP35) in folded, partially denatured, and fully denatured states. Experiments are carried out in frozen glycerol/water solutions, with chemical denaturation by guanidine hydrochloride (GdnHCl). Without GdnHCl, two-dimensional solid-state ¹³C NMR spectra of samples prepared with uniform ¹³C labeling of selected residues show relatively sharp cross-peaks at chemical shifts that are consistent with the known three-helix bundle structure of folded HP35. At high GdnHCl concentrations, most cross-peaks broaden and shift, qualitatively indicating disruption of the folded structure and development of static conformational disorder in the frozen denatured state. Conformational distributions at one residue in each helical segment are probed quantitatively with three solid-state NMR techniques that provide independent constraints on backbone ? and ψ torsion angles in samples with sequential pairs of carbonyl ¹³C labels. Without GdnHCl, the combined data are well fit by α-helical conformations. At [GdnHCl] = 4.5 M, corresponding to the approximate denaturation midpoint, the combined data are well fit by a combination of α-helical and partially extended conformations at each site, but with a site-dependent population ratio. At [GdnHCl] = 7.0 M, corresponding to the fully denatured state, the combined data are well fit by a combination of partially extended and polyproline II conformations, again with a site-dependent population ratio. Two entirely different models for conformational distributions lead to nearly the same best-fit distributions, demonstrating the robustness of these conclusions. This work represents the first quantitative investigation of site-specific conformational distributions in partially folded and unfolded states of a protein by solid-state NMR.     

超声引导经阴道射频消融治疗症状性子宫肌瘤的临床价值

目的:探讨超声引导经阴道射频消融治疗症状性子宫肌瘤的安全性和有效性。方法:选择39例症状性子宫肌瘤患者进行经阴道射频消融治疗。术前超声测量肌瘤体积,采用子宫肌瘤症状和生存质量调查表对患者的子宫肌瘤相关症状的严重程度以及生活质量情况进行评分,观察治疗前和治疗后3、6、9、12个月肌瘤体积缩小率、临床症状及生活质量的改善情况和治疗前后卵巢功能的变化情况。结果:射频消融平均手术时间25分钟,术中及术后均未见明显并发症。本组术前肌瘤体积为65.2±49.3 cm~3;术后3、6、9、12个月肌瘤体积分别为32.2±27.6 cm~3、21.2±18.2 cm~3、15.3±12.1 cm~3、10.3±9.8 cm~3,与术前相比均显著缩小(P0.05)。术前SSS评分为60.23±13.2,术后3、6、9、12个月SSS评分分别为42.2±11.4、21.1±10.2、15.4±10.3、12.2±9.7,与治疗前相比均明显下降(P0.05)。术前QOL评分为58.24±16.24,术后3、6、9、12个月QOL评分分别为70.3±20.3、81.4±8.6、86.3±7.6、88.2±9.1,与治疗前相比逐渐上升,差异有统计学意义(P0.05)。手术后3、6、9、12个月后患者的FSH、LH、E2水平与术前相比,差异均无统计学意义(P0.05)。结论:超声引导下经阴道射频治疗子宫肌瘤可以有效缩小肌瘤体积,改善患者的临床症状,并提高患者的生活质量。