Localization of Click Trains and Speech by Cats: the Negative Level Effect

Although localization of sound in elevation is believed to depend on spectral cues, it has been shown with human listeners that the temporal features of sound can also greatly affect localization performance. Of particular interest is a phenomenon known as the negative level effect, which describes the deterioration of localization ability in elevation with increasing sound level and is observed only with impulsive or short-duration sound. The present study uses the gaze positions of domestic cats as measures of perceived locations of sound targets varying in azimuth and elevation. The effects of sound level on localization in terms of accuracy, precision, and response latency were tested for sound with different temporal features, such as a click train, a single click, a continuous sound that had the same frequency spectrum of the click train, and speech segments. In agreement with previous human studies, negative level effects were only observed with click-like stimuli and only in elevation. In fact, localization of speech sounds in elevation benefited significantly when the sound level increased. Our findings indicate that the temporal continuity of a sound can affect the frequency analysis performed by the auditory system, and the variation in the frequency spectrum contained in speech sound does not interfere much with the spectral coding for its location in elevation.     

Is Migraine Primarily a Metaboloendocrine Disorder?

Purpose of the Review

The goals of this review are to evaluate recent studies regarding comorbidity between migraine and different metabolic and endocrine disorders and to discuss the role of insulin resistance as a common pathogenetic mechanism of these diseases.

Recent Findings

Recently, several studies showed that migraine is associated with insulin resistance, a condition in which a normal amount of insulin induces a suboptimal physiological response. All the clinical studies that used the oral glucose tolerance test to examine insulin sensitivity found that, after glucose load, there is in migraine patients a significant increase of both plasmatic insulin and glucose concentrations in comparison with controls. On the contrary, no association was found between migraine and type 2 diabetes, while type 1 diabetes seems to have a protective effect in the disease. Obesity and hypertension were shown to be risk factors for both episodic and chronic migraine. Metabolic syndrome has been recently associated mainly with migraine with aura and is now considered a risk factor also for medication overuse headache. Finally, a bidirectional association between migraine and hypothyroidism has been recently demonstrated, suggesting that common genetic or autoimmune mechanisms underlie both diseases.

Summary

Recent studies showed that insulin receptor signaling and the related physiological responses are altered in migraine and may have a relevant pathogenic role in the disease. Further studies are warranted in order to better elucidate mechanisms underlying insulin resistance in migraine in order to develop new therapeutic strategies for this debilitating disease.

     

Hydrodynamic electrospray ionization jetting of calcium alginate particles: effect of spray-mode,spraying distance and concentration

Hydrodynamic electrospray ionization jetting was applied for generating and characterizing calcium cross-linked alginate microparticles. These microparticles show different diameters and aspect ratios for three electrospray modes (dripping, conejet and multijet modes), four spraying distances (5, 10, 15 and 20 cm), and six spraying concentrations. Comparing the three different electrospray modes, we found that the conejet mode results in the smallest particle diameters, lowest aspect ratio and smallest variations over the parameter space mentioned above. For all spraying modes, the resultant particle diameters become independent of the spraying distance at a sprayed solute concentration ≥ 2.5%. The aspect ratio of microparticles varies significantly for different spraying modes and distances. An increasing aspect ratio of all spray modes was determined for sodium alginate spraying concentrations ≤ 1.5% and spraying distances of 20 cm; this phenomenon can be explained with the chain ejection effect. This systematic investigation offers a basic database for industrial applications of hydrodynamic electrospray ionization.

Hydrodynamic electrospray ionization jetting was applied for generating and characterizing calcium cross-linked alginate microparticles.     

计帧法在急性心肌梗死再灌注治疗中的应用

目的 :评价计帧法测定校正的心肌梗死溶栓治疗临床试验帧数 (CTFC)在急性心肌梗死再灌注治疗中的临床意义。方法 :90例急性心肌梗死患者行直接经皮冠状动脉腔内成形术 (PTCA)或溶栓失败后的挽救性PTCA治疗 ,介入治疗后根据患者住院期间有无心脏不良事件分为有心脏不良事件组 ( 2 6例 )和无心脏不良事件组 ( 64例 ) ,用计帧法测定梗死相关动脉的CTFC ,以CTFC 3 0帧为界将患者分为血流正常者和血流缓慢者两部分 ,观察两部分患者心功能、住院期间心脏不良事件发生率的差异。结果 :所有患者CTFC平均为 3 6 78± 16 3 2帧 ,左心室射血分数和CTFC负相关 (γ =-0 64P =0 0 1) ,住院期间有心脏不良事件组CTFC明显高于无不良事件组 ( 5 1 91± 18 2 1vs .2 5 73± 7 79) ,有显著性差异 (P =0 0 0 )。多元回归分析发现CTFC和心脏不良事件有良好的相关性 [OR =-1 73 ,95 %可信限 (CI) =-1 3 4～ -2 2 3 ,P =0 0 1]。ROC曲线分析表明CTFC能较好地预测住院期间是否发生心脏不良事件。血流正常和血流缓慢患者间射血分数和住院期间心脏不良事件发生率有显著性差异 (P <0 0 5 )。结论 :计帧法测定CTFC是一种较好的评价冠状动脉血流的方法 ,其结果和心功能、临床近期预后密切相关     

Genomic DNA of MCF-7 breast cancer cells not an ideal choice as positive control for PCR amplification based detection of Mouse Mammary Tumor Virus-Like Sequences

The identification of the etiology of breast cancer is a crucial research issue for the development of an effective preventive and treatment strategies. Researchers are exploring the possible involvement of Mouse Mammary Tumor Virus (MMTV) in causing human breast cancer. Hence, it becomes very important to use a consistent positive control agent in PCR amplification based detection of MMTV-Like Sequence (MMTV-LS) in human breast cancer for accurate and reproducible results. This study was done to investigate the feasibility of using genomic DNA of MCF-7 breast cancer cells to detect MMTV-LS using PCR amplification based detection. MMTV env and SAG gene located at the 3′ long terminal repeat (LTR) sequences were targeted for the PCR based detection. No amplification was observed in case of the genomic DNA of MCF-7 breast cancer cells. However, the 2.7 kb DNA fragment comprising MMTV env and SAG LTR sequences yielded the products of desired size. From these results it can be concluded that Genomic DNA of MCF-7 cell is not a suitable choice as positive control for PCR or RT-PCR based detection of MMTV-LS. It is also suggested that plasmids containing the cloned genes or sequences of MMTV be used as positive control for detection of MMTV-LS.     

5 117例股骨颈骨折患者流行病学调查分析

目的：分析2014至2019年收治的股骨颈骨折患者的流行病学特征及变化趋势。方法：对2014年1月至2019年12月期间广东省某三级甲等医院收治的股骨颈骨折患者资料进行回顾性分析,记录患者的性别、年龄、住院时间等数据,分析6年期间股骨颈骨折的流行病学特征及变化趋势。结果：共统计股骨颈骨折患者5 117例,男女比例为0.67:1,2014至2019年股骨颈骨折病例数总体呈逐年上升趋势;老年组、青壮年组、儿童组所占比例分别为70.22%、27.40%、2.38%;2014至2019年老年组患者所占比例逐步增加,青壮年组所占比例逐步下降;股骨颈骨折好发季节为冬季;88.27%的股骨颈骨折致伤原因为摔伤;70.50%的老年患者有合并症;43.37%的患者以急诊方式入院,91.12%的患者采用手术治疗。结论：2014至2019年股骨颈骨折病例数逐年上升,女性多于男性,老年女性为高发人群,70～79岁为高发病年龄段,冬季为股骨颈骨折的高发季节,应做好重点人群特定时间段的预防,以降低股骨颈骨折的发病率。     

NASA空间站航天员病症目录分析

目的对NASA空间站病症目录进行分析,为我国空间站医学保障设计和资源配置提供参考。方法对NASA空间探索任务病症清单(space medicine exploration medical condition list,SMEMCL)中的空间站病症进行应对优先情况汇总,并按照相应的标准进行分类及分级处理。结果按照应对优先等级划分,必须处理和酌情处理的病症占绝大多数(82.76%),属于不专项应对病症仅占很少部分。在对病症进行分类及分级后,可见分类中以临床病症占比例最大(82.72%);按照NASA病症分级标准(严重程度分级),属于轻中程度的病症最多(91.36%),极少部分属于严重病症。结论 NASA空间站病症目录详实全面,必须处理和酌情处理的轻中程度临床病症居多;在进行空间站航天员医学保障的设计和相关医学资源的配置时应重点考虑这部分病症,对其余病症适当兼顾。     

急诊科护士遭受躯体暴力的预测线索探讨

目的探讨急诊科护士发生躯体暴力的预测线索。方法对四川省和重庆市5所医院的急诊科进行观察性研究,由专人观察和记录患方的行为线索,并根据行为变化是否转化为躯体暴力分为躯体暴力组和非躯体暴力组,统计分析两组行为变化的例数和躯体暴力的行为方式,采用Logistic回归分析确定护士发生躯体暴力的特定预测线索。结果共观察287例患者,非躯体暴力组219例,转化为躯体暴力组68例,躯体暴力发生率23.7%。Logistic回归分析显示当患方出现紧握双拳(OR=6.334)、挑衅(OR=5.672)、抵制护理措施(OR=5.164)、大声争吵(OR=4.651)、紧跟护理人员(OR=3.334)或鲁莽(OR=3.172)是发生躯体暴力的最强预测线索(P0.05,P0.01)。结论急诊科发生躯体暴力比较普遍,应快速、方便、有效地评估患方潜在的躯体暴力风险,采取相应的防范措施,以减少躯体暴力风险的发生,避免急诊科护士受到身体和心理伤害。     

Shikonin protects chondrocytes from interleukin-1beta-induced apoptosis by regulating PI3K/Akt signaling pathway

Chondrocyte apoptosis is mostly responsible for the development and progression of osteoarthritis. IL-1β is generally served as an agent that induces chondrocyte apoptosis. Shikonin exerts its anti-inflammatory effect on cartilage protection in vivo. We aimed to explore the protective effect of shikonin on interleukin-1beta (IL-1β)-induced chondrocyte apoptosis and the potential molecular mechanisms. Chondrocytes were isolated from the joints of newborn Sprague-Dawley rats. The MTT assay and LDH cell death assay were used to determine the cell viability and chondrocyte apoptosis was detected by Annexin-V/PI staining and nucleosomal degradation. The contents of phosphorylated-PI3K (p-PI3k), phosphorylated-Akt (p-Akt), Bcl-2, Bax, and cytochrome c were detected by Western blotting. A quantitative colorimetric assay was used to detect the caspase-3 activity. Our results showed that pretreatment with shikonin (4 μM) inhibited cytotoxicity and apoptosis induced by IL-1β (10 ng/ml) in chondrocytes. Shikonin pretreatment also decreased the activity of IL-1β that decreased Bcl-2 expression and levels of p-PI3K and p-Akt, and increased Bax expression, cytochrome c release, and caspase-3 activation. It also reversed the activity of IL-1β that promoted the synthesis of matrix metalloproteinase-13 and inhibited the expression of tissue inhibitor of metalloproteinase-1 expression, with the net effect of suppressing extracellular matrix degradation. These data suggested that shikonin may protect chondrocytes from apoptosis induced by IL-1β through the PI3K/Akt signaling pathway, by deactivating caspase-3.