Occupational contact dermatitis in a gender perspective: North East Italian data 1996-2016

Background:Occupational contact dermatitis (OCD) ranks high among occupational diseases in Europe, but little is known as regards OCD and jobs in a gender perspective.Objectives:To evaluate sex prevalence of OCD according to occupational sectors and agents involved. 27381 patients (1996–2016) with suspected irritant/allergic contact dermatitis (ICD-ACD) were evaluated in North-Eastern Italy. Each patient underwent: a standardized questionnaire, a dermatologist/occupational physician evaluation and a patch test.Results:Females were younger at diagnosis (35.2 ± 11.6 years vs 37.7 ± 12.6 in males, p< 0.001) and had a lower ICD prevalence (OR 0.58, C.I. 95% 0.51 - 0.66, p < 0.001). Job categories most involved differed between sexes, with highest rank for healthcare professionals in females and machinery mechanics and filters for males. In females ACD percentage was higher in all job categories.Conclusions:OCD characteristics differ between sexes, according to intrinsic and extrinsic factors. Use of personal care products, housekeeping products and outdoor work activities may account for different sensitization profiles.     

西安市新型冠状病毒肺炎无症状感染者特征分析

目的 分析西安市新型冠状病毒肺炎(COVID-19)无症状感染者的特征,为更好地防控疫情提供参考依据。方法 收集疫情应急处置期间无症状感染者的现场流行病学调查资料,采用描述性流行病学方法进行分析。结果 截至2020年5月10日,西安市共报告无症状感染者25例(男12例,女13例),中位年龄46.0(18.5,65.0)岁,占全市17.24%(25/145)。其中15例(60.00%)为确诊病例密切接触者,8例(32.00%)有湖北旅居史,2例(8.00%)为无症状感染者的密切接触者;23例(92.00%)经聚集性疫情传染源溯源和确诊病例/无症状感染者密切接触者排查发现,1例(4.00%)为协查外市确诊病例密切接触者发现,1例(4.00%)为筛查高危地区来陕人群发现。25例无症状感染者末次暴露到首次核酸检测阳性中位时间为17.0 d,集中医学观察开始至首次核酸检测阳性中位时间为8.0 d,首次核酸检测阳性至转阴出院中位时间为14.0 d。CT显示78.57%(11/14)无症状感染者肺部存在不同程度的小结节影、斑片状影、磨玻璃样影和边界欠清晰状况。结论 无症状感染者主要经聚集性疫情调查和确诊病例/无症状感染者密切接触者排查发现。及时全面排查密切接触者并对其进行集中医学观察,能减少其可能造成的疫情持续传播。肺部影像学特征性改变可作为早期排查的重要参考。     

On the secondary stability of coated cementless hip replacement: parameters that affected interface strength

Unlike primary stability of coated cementless implants, their secondary stability has been poorly studied. This paper considers some theoretical aspects of the secondary stability of a coated cementless hip implant in a human femur. The bone is separated from the implant by a thin layer of microscopic peaks and troughs formed on the surface of the coating. The size of the peaks and troughs is very small compared with the macrosize of the implant stem and bone in contact. The study of the bone–stem contact by direct application of the finite element method is prohibitively costly. A two-scale asymptotic homogenisation procedure that takes into account the microgeometry of the interface layer and mechanical properties of bone and the implant material is applied to obtain effective, homogenised contact parameters. These parameters can be used in finite element analyses involving smooth interfaces, which require hundreds of times fewer finite elements. With the homogenisation technique and finite element analyses for a simplified design, two parameters were found to be most important—the normal contact stiffness and the friction coefficient. They both increase several times as bone grows into the rough surface of the implant and mineralises, thus providing a stronger interface and resulting in reduced micromotions.     

土茯苓对细胞免疫和体液免疫的影响

土茯苓水提取物在抗原致敏后及攻击后给药均明显地抑制了picryl chloride(PC)所致的小鼠接触性皮炎(PC-DTH)和绵羊红细胞(SRBC)所致的足蹠反应(SRBC-DTH),其中攻击后给药时作用较强.土茯苓还明显地抑制了二甲苯所致的耳壳及蛋清所致的小鼠足蹠炎症反应。此外,土茯苓对小鼠抗SR-BC 抗体形成的细胞数(IgM-及IgG-PFC 数)无明显影响,但其溶血空斑明显地较对照组为大,同时,血清溶血素水平未见降低,而呈增加趋势。以上结果表明,土茯苓对体液免疫反应无抑制作用,但可选择性地抑制细胞免疫反应,后者主要系影响致敏T 淋巴细胞释放淋巴因子以后的炎症过程。     

Occupational induction of hypersensitivity after an accidental exposure to chloromethylisothiazolinone and methylisothiazolinone (CMI/MI) in an industrial worker.

A process worker in a paper chemical plant developed an immediate local dermal irritation and delayed bullous dermatitis due to induction of hypersensitivity following an accidental exposure to chloromethylisothiazolinone and methylisothiazolinone (CMI/MI) biocide. Contact allergy to the isothiazolinone mixture was confirmed by skin patch testing. The dermatitis healed in four weeks, and the worker was advised to avoid all CMI/MI containing products. In a one-year follow-up he did not present with any further skin symptoms. Preventive measures are important for avoiding induction of hypersensitivity to concentrated CMI/MI solutions in industrial workers.     

Ischaemia induced alternans of action potential duration in the intact-heart: dependence on coronary flow, preload and cycle length

Clinical and experimental evidence relate action potential duration(APD) alternans to ischaemic heart disease and ventricular arrhythmias.The present investigation was performed to study the quantitativerelationship between APD alternans and the degree ofischaemia,loading conditions and cycle length (CL) in an intact heart. Monophasic action potentials (MAP) were simultaneously recordedby contact electrodes from two left (LV) undone right ventricular(RV) sites in 20 Langendorff-perfused rabbit hearts. The preparationswere subjected to global ischaemia at flow rates ranging from40% of normal flow to complete cessation of flow. Pacing wasperformed at either constant or regularly changing CL. The magnitudeof APD alternans was expressed as beat-to-beat differences inaction potential duration of two consecutive MAPs. During normalper fusion, neither very fast pacing at a CL of 200 ms nor periodicalrate switches resulted in persistent APD alternans. Pacing ata constant CL of 800 ms did not induce A PD alternans at completecessation of flow for 6 min. However, alternans developed progressivelyat a constant CL of 400 ms after 2.8±0.3 min of completeischaemia at the pre-loaded LV, andafter 4.6±0.4 minat the unloaded RV (P<0.01). The reduction of preload atthe LV from 15 to 5 mmftg end-diastolic pressure delayed developmentof APD alternans from 2.8±0.3 min to 4.3±0.4 min(P < 0.05) at 400 ms CL. Following graded under per fusionof 40%, 20% and 10% of initial flow, persistent APD alternansdeveloped in relation to the degree of flow reduction and increasedprogressively with duration ofischaemia. APD alternans at theLV always preceded the onset of APD alternans at the RV. Inexperiments with identical flow rates the shortest CL of 200ms resulted in the greatest and earliest initiation of APD alternanscompared to the longer CL (P<0.01, P<0.001). An increasein CL from 400 to 800 ms immediately abolished APD alternans,generated by the shorter CL, at any time during the 6 min periodof complete ischaemia. Similarly, increasing the cycle lengthfrom 200 or 400 to 600 ms eliminated APD alternans up to 6 minof ischaemia and significantly reduced its magnitude between7 and 10 min within a few beats. We conclude that persistent APD alternans is a characteristicfinding in the rabbit heart during global ischaemia. It is asensitive parameter of the severity of ischaemia and dependson the degree and duration of ischaemia as well as on the preload.The CL appears to have an independent effect on the generationof APD alternans, which is functionally separate from the effectof CL on the ischaemic burden. An eventual impact of these observationscould be the application of APD alternans as a diagnostic toolin electrophysiological examinations of myocardial ischaemiain experimental and clinical settings.     

Dogger bank itch. 4. An eczema-causing sulfoxonium ion from the marine animal, Alcyonidium gelatinosum [Bryozoa]

Repeated exposure to the marine bryozoan, Alcyonidium gelatinosum, frequently provokes an eczematous allergic contact dermatitis known as the "Dogger Bank Itch". The dermatitis, representing a severe occupational disease, is especially widely distributed among trawlermen working in the Dogger Bank area in the North Sea. The allergy is shown to belong to the type of cell-mediated hypersensitivity. The hapten has been identified as the (2-hydroxyethyl)dimethylsulfoxonium ion. The isolation, structure determination and synthesis are discussed.     

YAG激光与药物结合治疗文唇后接触性唇炎130例临床观察

目的探讨YAG激光与药物联合治疗文唇后接触性唇炎的疗效。方法随机选取130例文唇后接触性唇炎患者，应用美国Coherent公司生产的多功能多波长皮肤美容激光器（Nd：YAG激光）进行治疗，联合应用抗组胺药物等内服以及皮质类固醇激素外用。结果130例患者，完全治愈112例（占86．2％），显效16例（占12．3％），有效2例（占1．5％），无效为0，总有效率100％。结论YAG激光与药物结合治疗文唇后接触性唇炎获得满意疗效，具有创伤小，疗效高，副作用少，不留疤痕等特点。     

角膜屈光性手术后的屈光矫正

目的：探讨角膜屈光性手术后视力低下的原因及屈光矫正方法。方法：对施行RK、PRK、LASIK术后来我中心寻求进一步视力矫正的48例86只眼，经裂隙灯、电脑验光、角膜曲率仪、计算机辅助的角膜地形图、对比敏感度检查，以及主、客观验光，分析其视力下降、矫正不良的原因，并探讨选择框架眼镜、各种设计的软性接触镜(SCL)和透气性硬性接触镜(RGPCL)，以及角膜矫形镜(Ortho-K CL)等进行屈光再矫正的效果和特点。结果：28只眼并发圆锥角膜，95．8％视力≤0．1，全部利用不同设计的RGPCL矫正，70．8％矫正视力≥0．8。16只眼为高度近视、高度散光，86．2％视力≤0．1，利用RGPCL，SCL和Ortho-K CL矫正，76．5％矫正视力≥0．8。34只近视、散光眼和5只远视、散光眼，60．0％～61．8％视力低于0．4，利用框架眼镜和各类接触镜矫正，80．0％以上获得良好矫正视力。另有3只眼RK术后因遭撞击致角膜裂伤后形成角膜白斑，均选用加虹膜色彩的接触镜矫正。结论：RK、PRK、LASIK术后视力低下的主要原因是医源性圆锥角膜和高度近视、高度散光。积极选择验配各类适宜的接触镜可显著提高视力，RGPCL最为有效。