Abnormal Binaural Spectral Integration in Cochlear Implant Users

Bimodal stimulation, or stimulation of a cochlear implant (CI) together with a contralateral hearing aid (HA), can improve speech perception in noise However, this benefit is variable, and some individuals even experience interference with bimodal stimulation. One contributing factor to this variability may be differences in binaural spectral integration (BSI) due to abnormal auditory experience. CI programming introduces interaural pitch mismatches, in which the frequencies allocated to the electrodes (and contralateral HA) differ from the electrically stimulated cochlear frequencies. Previous studies have shown that some, but not all, CI users adapt pitch perception to reduce this mismatch. The purpose of this study was to determine whether broadened BSI may also reduce the perception of mismatch. Interaural pitch mismatches and dichotic pitch fusion ranges were measured in 21 bimodal CI users. Seventeen subjects with wide fusion ranges also conducted a task to pitch match various fused electrode–tone pairs. All subjects showed abnormally wide dichotic fusion frequency ranges of 1–4 octaves. The fusion range size was weakly correlated with the interaural pitch mismatch, suggesting a link between broad binaural pitch fusion and large interaural pitch mismatch. Dichotic pitch averaging was also observed, in which a new binaural pitch resulted from the fusion of the original monaural pitches, even when the pitches differed by as much as 3–4 octaves. These findings suggest that abnormal BSI, indicated by broadened fusion ranges and spectral averaging between ears, may account for speech perception interference and nonoptimal integration observed with bimodal compared with monaural hearing device use.     

The Associations between Smoking,Physical Inactivity,Obesity, and Asthma Severity in the General US Population

The purpose of this study was to examine the associations between smoking, physical inactivity, obesity, and asthma severity among US adults. The magnitude of these associations was very strong. For example, those who visited an emergency room in the past year were 60% more likely than those who did not to smoke; those who used an inhaler ≥15 times in the past month (versus those who did not use an inhaler) were 90% more likely to be physically inactive; and those who had asthma symptoms all the time in the past 30 days (versus those with no symptoms) were 80% more likely to be obese.     

Lingual vs. labial fixed orthodontic appliances: systematic review and meta‐analysis of treatment effects

The aim of this systematic review was to compare the therapeutic and adverse effects of lingual and labial orthodontic fixed appliances from clinical trials on human patients in an evidence‐based manner. Randomized and prospective non‐randomized clinical trials comparing lingual and labial appliances were included. Risk of bias within and across studies was assessed using the Cochrane tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Random‐effects meta‐analyses were conducted, followed by subgroup and sensitivity analyses. Six electronic databases were searched from inception to July 2015, without limitations. A total of 13 papers pertaining to 11 clinical trials were included with a total of 407 (34% male/66% female) patients. Compared with labial appliances, lingual appliances were associated with increased overall oral discomfort, increased speech impediment (measured using auditory analysis), worse speech performance assessed by laypersons, increased eating difficulty, and decreased intermolar width. On the other hand, lingual appliances were associated with increased intercanine width and significantly decreased anchorage loss of the maxillary first molar during space closure. Based on existing trials, there is insufficient evidence to make robust recommendations for lingual fixed orthodontic appliances regarding their therapeutic or adverse effects, as the quality of evidence was low.     

Ⅱ型糖尿病患者的动态血压观察

对３１例Ⅱ型糖尿病患者（其中糖尿病肾病组１６例，糖尿病无肾病组１５例）进行２４ｈ动态血压观察。结果提示：Ⅱ型糖尿病不论有否合并肾病，２４ｈ平均收缩压（２４ｈＳＢＰ）、白昼平均收缩压（ｄＳＢＰ）、夜间平均收缩压（ｎＳＢＰ）均显著高于对照组（Ｐ均＜０．０１）；糖尿病肾病组的ｎＳＢＰ／ｄＳＢＰ和ｎＤＢＰ／ｄＤＢＰ均显著高于对照组（Ｐ均＜０．０１）；糖尿病肾病组的ｎＳＢＰ、ｎＳＢＰ／ｄＳＢＰ和ｎＤＢＰ／ｄＤＢｐ均显著高于糖尿病无肾病组（Ｐ均＜０．０５）。Ⅱ型糖尿病患者ＡＢＰＭ主要表现为收缩期血压增高，而且在糖尿病肾病患者中，夜间血压下降不明显，失去了血压的正常昼夜节律变化。结果提示血压超负荷时间延长可能是糖尿病肾病发生和发展的因素之一。     

The timing of proton migration in membrane-reconstituted cytochrome c oxidase

In mitochondria and aerobic bacteria energy conservation involves electron transfer through a number of membrane-bound protein complexes to O2. The reduction of O2, accompanied by the uptake of substrate protons to form H2O, is catalyzed by cytochrome c oxidase (CcO). This reaction is coupled to proton translocation (pumping) across the membrane such that each electron transfer to the catalytic site is linked to the uptake of two protons from one side and the release of one proton to the other side of the membrane. To address the mechanism of vectorial proton translocation, in this study we have investigated the solvent deuterium isotope effect of proton-transfer rates in CcO oriented in small unilamellar vesicles. Although in H2O the uptake and release reactions occur with the same rates, in D2O the substrate and pumped protons are taken up first (tau(D) congruent with 200 micros, "peroxy" to "ferryl" transition) followed by a significantly slower proton release to the other side of the membrane (tau(D) congruent with 1 ms). Thus, the results define the order and timing of the proton transfers during a pumping cycle. Furthermore, the results indicate that during CcO turnover internal electron transfer to the catalytic site is controlled by the release of the pumped proton, which suggests a mechanism by which CcO orchestrates a tight coupling between electron transfer and proton translocation.     

结核病血清诊断中HSP65的应用前景分析

目的：通过评价HSP65抗原表达在结核病血清诊断中的效果,分析其应用前景。方法取活动期结核病患者63例纳入观察组,选取体检健康志愿者60例纳入对照组,就HSP65分别与38 kDa、16 kDa、LAM联合检测诊断对照组与观察组结核病。结果Western-blot结果显示,表达产物在相对分子量65 kμ处有一条表达带,在健康人血清阴性中则无表达带;特异度、敏感度与38 kPa基本一致,差异无统计学意义(P>0.05)。结论 HSP65在结核病血清诊断中可作为备选标志物,反应强度与38kDa基本相当,联合诊断有助于提高诊断符合率;HSP65对结核病X线空洞影敏感度较高。     

难溶性药物logP值对纳米脂肪乳载药特性的影响

目的 考察难溶性药物油/水分配系数(log P值)对纳米脂肪乳载药量、体外释药特性、相分布等载药特性的影响。 方法 选取6种难溶性药物:尼莫地平(NIM)、多西紫杉醇(DTX)、姜黄素(CUR)、紫杉醇(PTX)、替尼泊苷(TEN)、水飞蓟宾(SLB),分别考察其log P值与PEG400中溶解度、载药纳米脂肪乳的载药量、粒径、Zeta电位、体外释药特性以及相分布等的关系。 结果 随着log P值的增加,药物在PEG400中的溶解度呈先上升后下降的趋势,在纳米脂肪乳中的载药量增高,体外释放速率减慢,在油相中的分布增加,在乳化剂层的分布减小;药物log P值与载药纳米脂肪乳的粒径及Zeta电位无关。 结论 可综合考虑药物的log P值及PEG400中的溶解度,用以初步判断纳米脂肪乳的载药特性。