Development of contralateral and ipsilateral frequency representations in ferret primary auditory cortex

Little is known about the maturation of functional maps in the primary auditory cortex (A1) after the onset of sensory experience. We used intrinsic signal imaging to examine the development of the tonotopic organization of ferret A1 with respect to contralateral and ipsilateral tone stimulation. Sound-evoked responses were recorded as early as postnatal day (P) 33, a few days after hearing onset. From P36 onwards, pure tone stimuli evoked restricted, tonotopically organized patches of activity. There was an age-dependent increase in the cortical area representing each octave, with a disproportionate expansion of cortical territory representing frequencies > 4 kHz after P60. Similar tonotopic maps were observed following stimulation of the contralateral and ipsilateral ears. During the first few weeks following hearing onset, no differences were found in the area of cortical activation or in the magnitude of the optical responses evoked by stimulation of each ear. In older animals, however, contralateral stimuli evoked stronger responses and activated a larger A1 area than ipsilateral stimuli. Our findings indicate that neither the tonotopic organization nor the representation of inputs from each ear reach maturity until approximately 1 month after hearing onset. These results have important implications for cortical signal processing in juvenile animals.     

Neocortical hyperexcitability in a genetic model of absence seizures and its reduction by levetiracetam

PURPOSE: To study the effect of the antiepileptic drug levetiracetam (LEV) on the patterns of intrinsic optical signals (IOSs) generated by slices of the somatosensory cortex obtained from 3- and 6-month-old WAG/Rij and age-matched, nonepileptic control (NEC) rats. METHODS: WAG/Rij and NEC animals were anesthetized with enfluorane and decapitated. Brains were quickly removed, and neocortical slices were cut coronally with a vibratome, transferred to a submerged tissue chamber, and superfused with oxygenated artificial cerebrospinal fluid (aCSF). Slices were illuminated with a dark-field condensor and examined with a x2.5 objective; images were processed with a real time digital video image-enhancement system. Images were acquired before (background) and during electrical stimulation with a temporal resolution of 10 images/s and were displayed in pseudocolors. Extracellular stimuli (200 micros; <4 V) were delivered through bipolar stainless steel electrodes placed in the white matter. RESULTS: IOSs recorded in NEC slices bathed in control aCSF became less intense and of reduced size with age (p < 0.05); this trend was not seen in WAG/Rij slices. Age-dependent decreases in IOS intensity and area size were also seen in NEC slices superfused with aCSF containing the convulsant 4-aminopyridine (4-AP, 5 microM); in contrast, significant increases in both parameters occurred with age in 4-AP-treated WAG/Rij slices (p < 0.05). Under any of these conditions, the IOS intensity and area size slices were larger in WAG/Rij than in NEC slices. LEV (50-500 microM) application to WAG/Rij slices caused dose-dependent IOS reductions that were evident both in control and in 4-AP-containing aCSF and were more pronounced in 6-month-old tissue. CONCLUSIONS: These data demonstrate age-dependent IOS modifications in NEC and WAG/Rij rat slices and identify a clear pattern of hyperexcitability that occurs in 6-month-old WAG/Rij neocortical tissue, an age when absence seizures occur in all animals. The ability of LEV to reduce these patterns of network hyperexcitability supports the potential use of this new antiepileptic drug in primary generalized epileptic disorders.     

多巴染色与光密度法在细胞水平评价原料美白功效的应用研究

目的：在细胞水平评价化妆品原料的美白功效。方法：体外培养小鼠黑素瘤细胞B16,通过多巴特异性染色,利用平均光密度法检测化妆品原料对细胞中黑素生成的抑制作用。结果：多巴对细胞内黑素具有特异性染色,浓度为25μg/ml的曲酸对黑素细胞内黑素生成的抑制率为（48.44±3.44）%,板内标准偏差值仅为7.09%,板间标准偏差值小于7.22%,曲酸、白藜芦醇和绿茶提取物均对细胞内黑素的生成具有较为明显的抑制作用,而桑白皮提取物对细胞内黑素生成几乎没有抑制作用。结论：采用多巴染色和平均光密度的方法检测黑素瘤细胞中黑素含量,精度较高、板间板内误差较小,能够成功用于化妆品原料美白功效的评测。     

负压封闭引流治疗小鼠创面铜绿假单胞菌感染的效果及机制

目的 观察VSD对感染创面中铜绿假单胞菌生长的影响,并探讨其可能机制。 方法 选取健康成年雄性C57BL/6小鼠40只,按照随机数字表法分为对照组和治疗组,每组20只。无菌条件下切除各小鼠背部1 cm×1 cm的全层皮肤,将细菌荧光素酶目的基因luxCDABE标记的野生型铜绿假单胞菌菌株PAO1 -lux涂抹于创面,包扎创面24 h,制成铜绿假单胞菌感染小鼠模型。治疗组小鼠创面行VSD治疗（负压为-16.625 kPa）,对照组创面常规换药。分别于治疗前和治疗24 h时,用小动物活体成像系统检测2组小鼠创面PAO1-lux荧光强度,激光多普勒血流成像仪检测创面血流量,以实时荧光定量RT-PCR检测创缘组织IL-1β、血管内皮生长因子(VEGF)的mRNA表达水平。观察治疗24 h时2组小鼠创缘组织病理学特点。对实验数据行t检验。 结果(1)治疗前,治疗组小鼠创面PAO1 -lux荧光强度与对照组相近(t=0.03,P=0.98);治疗24 h时,治疗组的荧光强度为(2.69±0.75)光子·秒-1·厘米-2·单位角度-1(photons· s-1- cm-2·sr-1),明显低于对照组的(5.18±0.96)photons·s-1·cm-2·sr-1,t =3.54,P=0.02。(2)治疗前,治疗组小鼠创面血流量与对照组相似(t =0.50,P=0.64);治疗24 h时,治疗组创面血流量为(96±9)灌注单位,明显高于对照组的(70±11)灌注单位,t=3.13,P=0.04。(3)治疗前,2组小鼠创缘皮肤组织中IL-1β、VEGF mRNA表达水平接近（t=0.19,P=0.86;t=0.07,P=0.95）;治疗24h时,治疗组IL-1β、VEGF mRNA表达水平分别为4.72±0.37、2.68±0.39,均明显高于对照组的2.24±0.50、1.22±0.13,t值分别为6.90、6.12,P值均为0.00。(4)治疗24 h时,治疗组创缘皮肤组织内炎性细胞浸润数量较对照组增加约77％。 结论 与常规换药相比,VSD治疗在小鼠全层皮肤缺损早期即能明显降低创面铜绿假单胞菌含量。其机制可能与增加创面局部血流量、提高创面组织炎性细胞数量、促进IL-1β和VEGF的mRNA表达有关。     

A Case of In-Stent Neoatherosclerosis 10 Years after Carotid Artery Stent Implantation: Observation with Optical Coherence Tomography and Plaque Histological Findings

We report a patient''s case of slow progressive in-stent restenosis 10 years after bare-metal stent implantation to his carotid artery. We treated the patient with an additional stent placement under a distal filter protection device. Optical coherence tomographic assessment and plaque histology during the carotid artery stenting (CAS) revealed atheromatous change at in-stent neointima, which contained lipid-rich plaque and calcification deposits. These findings suggest that in-stent neoatherosclerosis may play an important role in the pathogenesis of very late stent restenosis after CAS.     

光学相干断层扫描血管成像对玻璃体腔注射雷珠单抗治疗湿性年龄相关性黄斑变性的随访观察

目的 利用光学相干断层扫描血管成像(OCTA)观察雷珠单抗玻璃体腔注射3次+必要时(3+PRN)方案治疗湿性年龄相关性黄斑变性(AMD)的图像特征。方法 选取2016年9月至2017年5月经荧光素眼底血管造影(FFA)、吲哚菁绿血管造影(ICGA)检查确诊且未予治疗的湿性AMD患者8例8只眼,按照3+PRN治疗方案给予玻璃体腔注射雷珠单抗(0.5 mg/0.05 ml)治疗,采用OCTA 6 mm×6 mm范围模式扫描黄斑区视网膜,在患者治疗前,治疗后1、3、6个月进行规律的门诊随访,记录患者最小分辨角对数(logMAR)矫正视力、脉络膜新生血管(CNV)分型、CNV形态特征及变化、黄斑中心凹视网膜厚度(CRT)、黄斑区视网膜外层血流密度(ORVD)及脉络膜毛细血管层血流密度(CCVD)。结果 男性4例4只眼,女性4例4只眼,平均年龄(70.9±10.6)岁;3只眼为Ⅰ型CNV,5只眼为Ⅱ型CNV。治疗前,治疗后1、3、6个月最佳矫正视力(BCVA)分别为0.55(0.33,0.87)、0.35(0.24,0.84)、0.35(0.22,0.58)、0.26(0.10,0.58)logMAR,各组间差异均无统计学意义(P均>0.05);CRT分别为(271.88±91.95)、(204.00±45.78)、(196.00±31.14)、(219.25±71.32)μm,其中,治疗3个月与治疗前差异有统计学意义(t=2.211,P=0.044);ORVD分别为(41.38±2.77)%、(41.73±3.60)%、(42.53±1.95)%、(41.40±2.33)%,各组间差异均无统计学意义(P均>0.05);CCVD分别为(64.38±2.24)%、(64.96±1.39)%、(64.16±1.39)%、(64.63±1.86)%,各组间差异也均无统计学意义(P均>0.05)。相关性分析结果显示,BCVA与CRT(P=0.009, RR=0.457)和CCVD(P=0.001,RR=0.574)显著相关,与ORVD(P=0.093,RR=0.302)不相关。治疗前CNV形态特征,2只眼为团状,2只眼为线条样,2只眼为纠缠错乱状,1只眼为椭圆环形,1只眼为碎片样。治疗1个月,7只眼CNV形态趋于正常化,表现为CNV最大直径减小、断裂/破碎、周边毛细血管丢失、数量和密度下降、所在区域最大横截面积减小;1只眼CNV形态较前恶化,表现为CNV吻合成环、密度增加、最大血管直径增加。治疗3个月,7只眼CNV形态趋于正常化,1只眼较前无明显变化。治疗6个月,5只眼CNV趋于正常化,3只眼恶化。随访中未发现眼内感染或玻璃体内注射的其他并发症。结论 利用OCTA技术观察CNV特征能够评估湿性AMD患者接受雷珠单抗治疗的疗效,可为湿性AMD患者的治疗与随访提供指导。     

扫频光学相干断层扫描根管内窥影像系统的建立及其在根裂诊断的应用

目的:建立扫频光学相干断层扫描(swept source-optical coherence tomography, SS-OCT)根管内窥影像系统,并评价该系统应用于诊断模拟根管内壁裂的准确性。方法:自主研发基于压电调谐滤波器并应用傅里叶(Fourier)域锁模技术构建的40 kHz超高速扫频激光光源系统(专利号200620135940.2),利用超微型梯度折射率透镜(专利号201320241218.7)制作极细根管内窥探头(直径0.86 mm),实现实时成像传输。构建的SS-OCT根管内窥影像系统扫频光源中心波长为1 310 nm,带宽为100 nm; 扫描图像的横向和纵向分辨率分别为25 μm和15 μm。利用人离体下颌前磨牙牙根制作人工模拟根裂(内壁裂),并制备高度1 mm的牙根横断面切盘。立体显微镜下观察发现,41个待测样本中有27个根管内壁裂样本(宽度在52~284 μm),另14个样本无根裂。应用上述构建的SS-OCT根管内窥影像系统扫描待测样本,重建图像的层厚为30 μm,层间距为30 μm。对1名口腔放射科医师和1名牙体牙髓科医师进行培训,判读SS-OCT扫描重建图像,判读根管内壁裂的有无及具体位置,评价两名观察者的自身一致性和观察者之间的一致性。以立体显微镜(组织学)检查结果作为金标准,评价应用SS-OCT根管内窥影像系统诊断模拟根管内壁裂的准确性。结果:两位观察者自身一致性的Kappa值分别为1.000和0.709,观察者之间的Kappa值为0.792。应用SS-OCT根管内窥影像系统扫描后27个根裂样本均被正确诊断,灵敏度为1.000,14个无根裂的样本有12个被正确判读,特异度为0.857, 2个无根裂样本被判读为有根裂,为假阳性。阳性预测值、阴性预测值分别为0.931、1.000,准确性为0.951。结论:扫频光学相干断层扫描根管内窥影像系统应用于观察根管内壁裂有临床应用前景。     

The “silent” imprint of musical training

Playing a musical instrument at a professional level is a complex multimodal task requiring information integration between different brain regions supporting auditory, somatosensory, motor, and cognitive functions. These kinds of task‐specific activations are known to have a profound influence on both the functional and structural architecture of the human brain. However, until now, it is widely unknown whether this specific imprint of musical practice can still be detected during rest when no musical instrument is used. Therefore, we applied high‐density electroencephalography and evaluated whole‐brain functional connectivity as well as small‐world topologies (i.e., node degree) during resting state in a sample of 15 professional musicians and 15 nonmusicians. As expected, musicians demonstrate increased intra‐ and interhemispheric functional connectivity between those brain regions that are typically involved in music perception and production, such as the auditory, the sensorimotor, and prefrontal cortex as well as Broca's area. In addition, mean connectivity within this specific network was positively related to musical skill and the total number of training hours. Thus, we conclude that musical training distinctively shapes intrinsic functional network characteristics in such a manner that its signature can still be detected during a task‐free condition. Hum Brain Mapp 37:536–546, 2016. © 2015 Wiley Periodicals, Inc.     

Prediction of the response to photodynamic therapy in patients with chronic central serous chorioretinopathy based on optical coherence tomography using deep learning

PurposeTo assess the prediction of the response to photodynamic therapy (PDT) in chronic central serous chorioretinopathy (CSCR) based on spectral-domain optical coherence tomography (SD-OCT) images using deep learning (DL).MethodsRetrospective study including 216 eyes of 175 patients with CSCR and persistent subretinal fluid (SRF) who underwent half-fluence PDT. SD-OCT macular examination was performed before (baseline) and 3 months after treatment. Patients were classified into groups by experts based on the response to PDT: Group 1, complete SRF resorption (n = 100); Group 2, partial SRF resorption (n = 66); and Group 3, absence of any SRF resorption (n = 50). This work proposes different computational approaches: 1st approach compares all groups; 2nd compares groups 1 vs. 2 and 3 together; 3rd compares groups 2 vs. 3.ResultsThe mean age was 55.6 ± 10.9 years and 70.3% were males. In the first approach, the algorithm showed a precision of up to 57% to detect the response to treatment in group 1 based on the initial scan, with a mean average accuracy of 0.529 ± 0.035. In the second model, the mean accuracy was higher (0.670 ± 0.046). In the third approach, the algorithm showed a precision of 0.74 ± 0.12 to detect the response to treatment in group 2 (partial SRF resolution) and 0.69 ± 0.15 in group 3 (absence of SRF resolution).ConclusionDespite the high clinical variability in the response of chronic CSCR to PDT, this DL algorithm offers an objective and promising tool to predict the response to PDT treatment in clinical practice.     

家庭赋权干预对永久性肠造口患者照顾者的影响

目的 探讨家庭赋权干预应用于永久性肠造口患者主要照顾者的效果。 方法 选择永久性肠造口患者及主要照顾者97对作为研究对象,按照患者住院时间分为对照组48对和观察组49对。对照组患者给予常规护理,观察组在对照组基础上实施家庭赋权干预方案。比较两组照顾者干预前后照顾准备程度、照顾负担及心理一致感评分。 结果 干预后,观察组照顾者照顾准备度评分及心理一致感评分显著高于对照组,照顾负担评分显著低于对照组（均P＜0.05）。 结论 家庭赋权干预有利于提高永久性肠造口患者主要照顾者的准备度及心理一致感,对缓解照顾者照顾负担具有积极意义。