Polypyrrole-coated electrodes for the delivery of charge and neurotrophins to cochlear neurons

Sensorineural hearing loss is associated with gradual degeneration of spiral ganglion neurons (SGNs), compromising hearing outcomes with cochlear implant use. Combination of neurotrophin delivery to the cochlea and electrical stimulation from a cochlear implant protects SGNs, prompting research into neurotrophin-eluting polymer electrode coatings. The electrically conducting polypyrrole/para-toluene sulfonate containing neurotrophin-3 (Ppy/pTS/NT3) was applied to 1.7 mm² cochlear implant electrodes. Ppy/pTS/NT3-coated electrode arrays stored 2 ng NT3 and released 0.1 ng/day with electrical stimulation. Guinea pigs were implanted with Ppy/pTS or Ppy/pTS/NT3 electrode arrays two weeks after deafening via aminoglycosides. The electrodes of a subgroup of these guinea pigs were electrically stimulated for 8 h/day for 2 weeks. There was a loss of SGNs in the implanted cochleae of guinea pigs with Ppy/pTS-coated electrodes indicative of electrode insertion damage. However, guinea pigs implanted with electrically stimulated Ppy/pTS/NT3-coated electrodes had lower electrically-evoked auditory brainstem response thresholds and greater SGN densities in implanted cochleae compared to non-implanted cochleae and compared to animals implanted with Ppy/pTS-coated electrodes (p < 0.05). Ppy/pTS/NT3 did not exacerbate fibrous tissue formation and did not affect electrode impedance. Drug-eluting conducting polymer coatings on cochlear implant electrodes present a clinically viable method to promote preservation of SGNs without adversely affecting the function of the cochlear implant.     

Non pharmacological treatment of severe cutaneous infections: hyperbaric oxygen therapy, dressings and local treatments

Beside conventional therapy, the management of necrotizing cellulitis and fasciitis is based on non-pharmacological treatments. Hyperbaric oxygen therapy and dressings are the most frequently used techniques. The usefulness of hyperbaric oxygen therapy is clearly demonstrated in experimental studies while the efficacy of this technique is poorly assessed in clinical practice. The French consensus conference has concluded to an adjuvant role of hyperbaric oxygen therapy combined to intensive care management, surgery and antibiotic therapy. Occlusive conventional dressings using humid or vaseline gauze dressings are largely used. Calcium alginate or silver coated dressings might be useful. In addition, vacuum-assisted closure therapy could be proposed in replacement of conventional dressings.     

Quantification of mobility impairment and self-assessment of stiffness in patients with myotonia congenita by the physiotherapist

We investigated test-retest reliability and responsiveness in two functional measuring instruments, Timed Up&Go (TUG) and Timed-Stands Test (TST), and in three self-assessment scales, Visual Analogue Scale (VAS), Borg's Category-Ratio Scale (BorgCR10) and Myotonia Behaviour Scale (MBS) when quantifying myotonic stiffness and mobility impairment. These methods were used in the assessment of treatment efficacy of mexiletine. Six male patients with myotonia congenita followed a standardised protocol with time scoring and rest on two occasions, with and without mexiletine. Time scoring of TUG and TST and self-assessments of stiffness were performed. A 14-day stiffness diary was used at home. Timed Up&Go and TST showed very good test-retest agreement (ICC=0.87-0.95) and significant to change (P=0.005 and 0.001, respectively). All self-assessment scales revealed excellent responsiveness and good test-retest reliability. The measurement instruments possess great capacity to detect functional impairment in the myotonia congenita patient group, and sensibility to identify true changes due to treatment. When considering the results, three instruments are favoured; Timed Up&Go and BorgCR10 for short, and MBS for long-term evaluations.     

Cardiac resynchronization performed by LBBaP-CRT in patients with cardiac insufficiency and left bundle branch block

Objective

To evaluate the efficacy and safety of left bundle branch area pacing (LBBaP) in patients with heart failure and left bundle branch block (LBBB), and to compare the clinical effects with traditional cardiac resynchronization therapy (CRT).

Methods

Thirty-two patients with dilated cardiomyopathy complicated by cardiac insufficiency and left bundle branch block were divided into CRT group and LBBaP group. Parameters including pacing threshold, R-wave amplitude, pacing impedance and operation time, and X-ray exposure time were recorded. The left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), and left ventricular end-systolic diameter (LVESD) were examined by echocardiography. The changes of QRS complex before and after operation were compared.

Results

Compared with CRT group, the LBBaP group spent less time on total operation time and X-ray exposure time and had stable electrode parameters including pacing threshold, R-wave amplitude, and lead impedance after 12-month follow-up. In addition, LBBaP can achieve narrow QRS complex (117.15 ± 9.91) ms immediately than that in CRT group (130.32 ± 12.41) ms. The change of QRS between LBBaP is (50.30 ± 23.79) ms and CRT group is (33.15 ± 20.22) ms. After 6 months' follow-up in LBBaP group, EF was higher than that before operation. Followed up for 12 months after operation, EF and LVEDD in LBBaP group were significantly improved compared with those before operation.

Conclusion

Left bundle branch area pacing is a safe and effective resynchronization method for patients with cardiac insufficiency and asynchronization, which can achieve same clinical effects to CRT.

     

左精索-髂外静脉分流联合精索静脉高位结扎术治疗胡桃夹综合征合并精索静脉曲张临床资料分析

 目的 总结胡桃夹综合征(nutcracker syndrome, NCS)合并中重度左侧精索静脉曲张(varicocele,VC)的临床特点及手术方法。方法 回顾性分析2012-07至2019-07民航总医院收治NCS伴有左侧VC患者8例。年龄15～54岁,平均25岁;平均体重指数18.3。临床表现为阴囊坠胀、疼痛,查体为中重度的左侧VC,精液分析示少精症或弱精症,尿常规示红细胞(+～+++)、蛋白(+～++)。彩超及腹部血管强化CT示腹主动脉与肠系膜上动脉夹角缩小压迫左肾静脉,平均夹角23.4°,左肾静脉的肾门处与受压处直径比较高,平均为5.1。所有患者均行左精索-髂外静脉分流术联合左精索静脉高位结扎术,术中于腹膜后将左侧精索静脉离断,近端与左髂外静脉端侧吻合,远端结扎。结果 手术均获成功,无切口感染、血栓形成等并发症。随访6个月,患者阴囊症状消失,尿潜血和尿蛋白转阴,阴囊彩超未探及精索静脉反流,术后的左肾静脉肾门处与受压处直径比、精子活力a+b级比率较术前有明显好转,差异有统计学意义(P<0.001),术后精子密度与术前相比无统计学差异。结论 NCS是临床少见疾病,常合并VC、血尿、蛋白尿,左精索-髂外静脉分流联合精索静脉高位结扎术治疗NCS合并VC是安全、有效的。     

梅尼埃病患者术后焦虑分析及其与生活质量的关系

目的：探讨梅尼埃病患者手术治疗后的焦虑及其与生活质量的关系。方法：2010年至2016年间收治住院 行内淋巴囊减压手术的68例梅尼埃病患者(梅尼埃病组),通过邮寄方式开展焦虑自评量表、梅尼埃病内淋巴囊减压 术生活质量调查问卷的回顾性随访调查。按术前病程、术后随访时间、临床分期、内淋巴囊减压术后生活质量有无 改善等指标,将梅尼埃病患者进行分组,分别进行焦虑分析。另选109例性别、年龄相匹配,因耳鼻咽喉方面其他 疾病接受手术的患者,填写焦虑量表作为对照组,与梅尼埃病组进行焦虑比较。结果：术前病程小于1年组、1~5年 组、大于5年组的梅尼埃病患者术后焦虑程度差异均无统计学意义(均P>0.05);术后随访时间小于24个月组和大于或 等于24个月组的梅尼埃病患者术后焦虑程度差异无统计学意义(P>0.05);不同临床分期组的梅尼埃病患者术后焦虑程 度差异均无统计学意义(均P>0.05);梅尼埃病患者术后生活质量有改善组和无改善组间焦虑程度差异无统计学意义 (P>0.05)。梅尼埃病组与对照组相比,焦虑更普遍、更严重(P<0.01)。结论：梅尼埃病患者术后仍存在一定程度的焦 虑,值得关注。     

低常远视力飞行学员3年远视力和屈光状态追踪观察

目的 追踪观察低常远视力飞行学员远视力及屈光动态变化,为现行招飞体检标准的可行性提供客观依据.方法 以空军航空航天大学2008年入校飞行学员27 1人为追踪对象,选择招飞时单眼或双眼远视力≥0.8且＜1.0（低常远视力）者为观察组;双眼远视力≥1.0（正常远视力）者为对照组;分别对3年（2009年、2010年和2011年）组内及组间远视力和屈光各变量进行比较分析.结果 远视力中位数：观察组3年分别为1.04、0.94和1.20,其中前2年与对照组比较差异均有统计学意义（Z=-9.034,P=0.000;Z=-12.829,P=0.000）,第3年差异无统计学意义（Z=-0.210,P=0.834）.远视力达标率：观察组3年分别为97.67％和97.65％和93.62％,其中由低常转为正常（≥1.0）比例分别为83.14％、45.89％和80.85％,组内比较差异有统计学意义（x 2=127.152,P=0.000）.静态屈光构成：与招飞时比较,观察组近视不同程度减少,其他屈光构成变化及趋势与对照组基本一致,3年组间比较差异均有统计学意义（2009年x2=9.366,P=0.025、2010年x 2=9.944,P=0.019和2011年x2=17.165,P=0.001）.静态屈光超标率：观察组3年分别为39.53％、28.65％和23.61％,与对照组比较,前2年差异无统计学意义（x2=4.880,P=0.087;x2=4.995,P=0.082）,第3年差异有统计学意义（x2=4.614,P=0.010）.结论 低常远视力飞行学员3年远视力呈提高态势,屈光状态趋于稳定,与对照组比较差异逐步缩小.提示在严格控制静态屈光的前提下,对非战斗机种飞行学员下调远视力合格标准至0.8是可行的.     

Full endoscopic endonasal transclival approach: Meningioma attached to the ventral surface of the brainstem

BackgroundIntracranial meningiomas without dural attachment (MWODA) are rare entities. We present the first case published, to the best of our knowledge, regarding a MWODA attached to the ventral surface of the brainstem. This location makes the patient subsidiary to treatment through an expanded endonasal transclival approach.Clinical presentationA 16-year-old female with suspected diagnosis of recurrence of a clear cell meningioma (CCM) at a distance from the initial lesion, located on the premedullary cistern. The patient underwent a pure endoscopic low transclival approach. The attachment to the ventral surface of the brainstem was confirmed intraoperatively. Postoperative MRI confirmed gross total resection and treatment was complemented with adjuvant fractionated stereotactic radiotherapy. No complications related to the procedure were observed.ConclusionMWODA may appear attached to the ventral brainstem. The expanded endonasal approach to the clivus provides a critical anatomical advantage in the treatment of medial lesions, even ventral meningiomas, to the lower cranial nerves. Reconstruction principles must be strictly respected to reduce complications.     

Effects of continuous intermedin infusion on blood pressure and hemodynamic function in spontaneously hypertensive rats

Objective To examine the effects of exogenously administered intermedin (IMD, adrenomedullin-2) on arterial blood pressure, cardiac function and the cardiovascular IMD receptor system in spontaneously hypertensive rats (SHRs) as well as to investigate the associated mechanisms. Methods Thirteen week-old male rats were divided in Wistar Kyoto (WKY) group (n = 12), SHR group (n = 12), IMD group (SHRs infused with IMD 1-47 500 ng/kg per hour, n = 12), and ADM group (SHRs infused with adrenomedullin 500 ng/kg per hour, n = 12). Results A two-week continuous administration of low dose IMD 1-47 via mini-osmotic pumps markedly reduced blood pressure, the maximal rates of increase and decrease of left-ventricle pressure development (LV ± dp/dtmax), left ventricular systolic pressure and heart rate in SHRs. Furthermore, IMD also inhibited protein over-expression of cardiovascular IMD receptors, myocardial Receptor Activity-Modifying Proteins (RAMP1 and RAMP2), aortic RAMP1, RAMP2, RAMP3, and calcitonin receptor-like receptor (CRLR); suppressed up-regulation of aortic RAMP1, RAMP2, RAMP3 and CRLR gene expression; and markedly elevated the mRNA abundance of myocardial atrial natriuretic peptide (ANP) and myocardial brain natriuretic peptide (BNP). Additionally, IMD 1-47 administration in SHRs increased aortic cAMP concentration and reduced myocardial cAMP concentration. Conclusion These findings support the speculation that IMD, as a cardiovascular active peptide, is involved in blood pressure reduction and cardiac function amelioration during hypertension. The mechanism underlying this effect may involve IMD binding of a receptor complex formed by RAMPs and CRLR, and consequential regulation of cAMP levels and other cardiovascular active factors, such as ANP and BNP.