Spatial distribution and spread potential of sixteen Leptospira serovars in a subtropical region of Brazil

Leptospirosis is a bacterial disease that represents a major problem in animal and public health due to its high prevalence and widespread distribution. This zoonotic disease is most prevalent in tropical environments where conditions favour pathogen survival. The ecological preferences of Leptospira serovars are poorly understood, limiting our knowledge of where and when outbreaks can occur, which may result in misinformed prevention and control plans. While the disease can occur consistently in time and space in tropical regions, research on the ecology of leptospirosis remains limited in subtropical regions. This research gap regarding Leptospira ecology brings public and veterinary health problems, impacting local economies. To fill this gap of knowledge, we suggest to assess geographic and ecological features among Leptospira serovars in a subtropical area of Brazil where leptospirosis is endemic to (a) highlight environmental conditions that facilitate or limit Leptospira spread and survival and (b) reconstruct its geographic distribution. An ecological niche modelling framework was used to characterize and compare Leptospira serovars in both geographic and environmental space. Our results show that despite the geographic overlap exhibited by the different serovars assessed, we found ecological divergence among their occupied ecological niches. Ecological divergences were expressed as ranges of potential distributions and environmental conditions found suitably by serovar, Sejroe being the most asymmetric (<0.15). Most important predictors for the potential distribution of most serovars were soil pH (31.7%) and landscape temperature (24.2%). Identification of environmental preferences will allow epidemiologists to better infer the presence of a serovar based on the environmental characteristics of regions rather than inferences based solely on historical epidemiological records. Including geographic and ecological ranges of serovars also may help to forecast transmission potential of Leptospira in public health and the food animal practice.     

Cortical activity patterns predict robust speech discrimination ability in noise

The neural mechanisms that support speech discrimination in noisy conditions are poorly understood. In quiet conditions, spike timing information appears to be used in the discrimination of speech sounds. In this study, we evaluated the hypothesis that spike timing is also used to distinguish between speech sounds in noisy conditions that significantly degrade neural responses to speech sounds. We tested speech sound discrimination in rats and recorded primary auditory cortex (A1) responses to speech sounds in background noise of different intensities and spectral compositions. Our behavioral results indicate that rats, like humans, are able to accurately discriminate consonant sounds even in the presence of background noise that is as loud as the speech signal. Our neural recordings confirm that speech sounds evoke degraded but detectable responses in noise. Finally, we developed a novel neural classifier that mimics behavioral discrimination. The classifier discriminates between speech sounds by comparing the A1 spatiotemporal activity patterns evoked on single trials with the average spatiotemporal patterns evoked by known sounds. Unlike classifiers in most previous studies, this classifier is not provided with the stimulus onset time. Neural activity analyzed with the use of relative spike timing was well correlated with behavioral speech discrimination in quiet and in noise. Spike timing information integrated over longer intervals was required to accurately predict rat behavioral speech discrimination in noisy conditions. The similarity of neural and behavioral discrimination of speech in noise suggests that humans and rats may employ similar brain mechanisms to solve this problem.     

帕金森病与颤证的差异与交融

目的:西医学所命名的"帕金森病"大致可归属于中医学"颤证"的范畴,文章旨在阐明两病的差异与交融,以期更好的指导临床实践。方法:首先,梳理颤证的相关理论,并开展颤证的中医现代辨证规律研究;其次,明确目前多数医家对帕金森病病机及证候分型的认识,并在此基础上开展帕金森病中医证候学的相关研究;最后,对比前后两项研究结果,得出结论。结果:两病的主要症状相似,但在病证所辖范围、病位及基本证型和证候要素等方面均有所不同。结论:可以参究颤证,探讨帕金森病的证候学规律,为丰富和发展中医辨治帕金森病理论,提高临床诊疗水平提供参考。     

Molecular structure of the SWA2 gene encoding an AMY1-related α-amylase from Schwanniomyces occidentalis

A 2.1-kb DNA fragment containing the SWA2 gene determining an -amylase from Schwanniomyces occidentalis has been sequenced. It contains an open reading frame of 1521 bp which has the potential to encode a 507 amino-acid protein of Mr 55966. Its deduced aminoacid sequence shows significant similarities to the sequence of other studied -amylases. These similarities identify a consensus sequence, F(LIV)(ED)NHD, which is shared in addition by most maltases, invertases and glucoamylases.     

Age and Mothers: Potent Influences of Children’s Skin Microbiota

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用HPLC指纹图谱全定性全定量控制通宣理肺丸质量

目的建立通宣理肺丸HPLC指纹图谱。方法采用反相高效液相色谱法,以色谱指纹图谱指数F为目标函数优化选择指纹图谱条件,以双定性相似度（SF与SF′）和双定量相似度（C与P）评价通宣理肺丸真实质量。结果以黄芩苷峰为参照物峰,确定了77个共有峰,通过聚类分析确定用10个厂家制剂生成对照指纹图谱（RFP）,以此评价14个不同厂家的通宣理肺丸质量。结论所建立的HPLC指纹图谱特征性、专属性强且有较好的稳定性,为通宣理肺丸质控提供了新参考。     

用HPLC指纹图谱宏观全定性全定量评价天麻质量

目的采用双定性双定量相似度为评价指标,建立宏观全定性全定量控制天麻质量的方法。方法采用反相HPLC法．以色谱指纹图谱指数F为目标函数优化选择指纹图谱条件．测定12批不同产地天麻HPLC指纹图谱,以双定性相似度（SF与SF’）和双定量相似度（C与P）评价不同产地天麻质量。结果以天麻素峰为参照物峰。确定26个指纹峰．通过聚类分析确定用8批天麻生成对照指纹图谱（RFP）,以此评价12个产地的天麻药材质量。结论所建立指纹图谱具有较好的精密度和重现性,可作为天麻药材质量控制和真伪鉴别的有效方法。     

玄参的毛细管电泳指纹图谱研究

目的建立玄参药材的毛细管电泳指纹图谱（CEFP）。方法采用毛细管区带电泳法,以50 mmol.L-1硼砂为背景电解质,运行电压12.1 kV,检测波长280 nm,重力进样20 s（高度8.5 cm）,以10个不同产地药材的电泳图谱建立了玄参CEFP。用＂中药色谱指纹图谱超信息特征数字化评价系统3.0＂软件获得相关指纹峰特征参数,用双定性相似度（SF与S′F）和双定量相似度（C与P）分别评价。对玄参CEFP进行了破坏性试验考察并考察了大峰和小峰分别缺失时4个相似度指标变化特征。结果以哈巴俄苷峰为参照物峰,按共有峰出现率100%确定10个共有指纹峰,建立了玄参CEFP。采用DQDQS法评价出3批质量完全合格,4批含量明显偏低,3批含量明显偏高。破坏性试验结果表明玄参CEFP指纹在碱性条件下极易降解,其次在酸性条件和氧化作用下也发生降解。采用混批勾兑技术按含量相似度105%计算了两类含量高低不同样品的勾兑系数。结论由SF与S′F和C与P构成的双定性双定量相似度（DQDQS）法能同时监测大峰和小峰的变动和缺失,能准确的解决色谱指纹图谱的宏观定性和定量评价的关键问题,所建立的CEFP为玄参药材质量控制提供了新方法。     

知母HPLC指纹图谱的4种相似度评估

目的用双定性双定量相似度法评价知母HPLC指纹图谱.方法采用反相高效液相色谱法,使用Century SIL C18BDS柱(20 cm×4.6mm,5μm),以1%醋酸水-1%醋酸乙腈为流动相,梯度洗脱,检测波长265 nm,柱温(30.0±0.15)℃,进样量5μL,测定10批知母HPLC指纹图谱.以双定性相似度SF和S'F、双定量相似度C%和P%评价知母HPLC指纹图谱.分别考察在大峰缺失和小峰缺失两种情况下,4个相似度指标变化特征.结果以芒果苷为参照物峰,确定21个共有峰,建立了知母HPLC指纹图谱.SF能反映化学成分分布比例,受大峰影响严重,无法反映小峰丢失;S'F、对所有指纹峰等权,反映小峰缺失灵敏.C%能反映样品总体含量,但受大峰影响严重,无法反映小峰缺失;P%对所有峰积分值等权,能较好反映小峰变动.结论双定性相似度SF与S'F、双定量相似度C%与P%能准确反映大峰和小峰的含量变动与缺失.所建立的HPLC指纹图谱可用于知母质量控制.     

Neuromyelitis optica spectrum disorders may be misdiagnosed as Wernicke's encephalopathy

Purpose: To raise doctors’ attention to the differential diagnosis of neuromyelitis optica spectrum disorders (NMOSD) and Wernicke's encephalopathy (WE). Patients and methods: We extensively reviewed the medical records of 136 patients who had visited our hospital since 2008 and were suspected of having central nervous system demyelinating diseases. Four of those patients had somnolence, electrolyte imbalance and brain lesions around the third ventricle and were included in the study. We tested the serum of the four patients for the presence of aquaporin-4 (AQP4) M23 antibody. Results: All the four patients had positive AQP4 antibody in their serum. Two of the patients were misdiagnosed as WE before AQP4 antibody detection occurred. Conclusions: NMOSD and WE have similar brain lesion locations, histopathological changes and clinical manifestations. It is important to distinguish NMOSD from WE by detecting AQP4 antibody in serum or cerebral spinal fluid. Vitamin B1 should also be administered to the patients who have a history of thiamine deficiency.