A Reliable Method for Quantification of Tendon Structure Using B‐Mode Ultrasound

Structure is an important clinical marker of tendon health; however, current standards use qualitative scores that are not strongly reliable. Therefore, the purpose of this study was to establish the reliability of an image‐processing technique that quantifies tendon collagen structure using B‐mode ultrasound images. Longitudinal images of the Achilles tendon were collected in 12 healthy young adults, and intra‐ and inter‐rater reliability was assessed over multiple image selections and multiple days. Intraclass correlation coefficients were strong (r ≥ 0.71) for all comparisons. These findings demonstrate that quantitative assessments of tendon structure using B‐mode ultrasound are reliable.     

Genetic Characterization of Toxoplasma gondii from Zoo Wildlife and Pet Birds in Fujian,China

Background:

Toxoplasmosis, a worldwide zoonotic disease, is caused by Toxoplasma gondii. The distribution of genetic diversity of T. gondii in wild animals is of great importance to understand the transmission of the parasite in the environment. However, little is known about T. gondii prevalence in wild animals and birds in China.

Methods:

We conducted the genetic characterization of T. gondii isolated from Zoo Wild Animals and Pet Birds in Fujian Province, Southeastern China. Heart tissues were collected from 45 zoo animals and 140 pet birds. After identified using B1 gene, the genetic diversity of T. gondii isolates were typed at 11 genetic markers, including SAG1, 5’ and 3’-SAG2, alternative SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3.

Results:

Seven of 45 zoo animals and 3 of 140 pet birds were positive by PCR amplification using T. gondii B1 gene specific primers. Of these positive isolates, 3 isolates from Black-capped (Cebus apella), Peacock (Peafowl) and Budgerigar (Melopsittacus undulatus) were successfully genotyped at 11 genetic loci, and grouped to three distinct genotypes: ToxoDB Genotype #9, #2 and #10, respectively.

Conclusion:

This is the first genotyping of T. gondii isolated from zoo wild animals and pet birds in Fujian, China. There is a potential risk for the transmission of this parasite through zoo wild animals and pet birds in this region.     

Hazard identification of cis/trans-zearalenone through the looking-glass

Among the food-related health issues, the presence of contaminants has a prominent role, due to the wide range of exogenous compounds that can occur in food commodities and to their large differences in structure and biological activity. A comprehensive assessment of the related risk is thus actually demanding in terms of time and facilities involved. In this context, the use of computational strategies can be an effective choice for supporting the hazard identification procedure at the early stage. In this work, we focused on the food contaminant zearalenone by comparing the trans and cis isomers, respectively the well-known mycoestrogen and its still largely understudied isomer. We estimated the possible effects exerted by human metabolism on the xenoestrogenicity of cis-ZEN by using a validated in silico strategy based on docking simulations and rescoring procedures. Similarly, the exploitation of the most promising enzymatic detoxifying routes designed for trans-ZEN – which relies on the enzyme lactono hydrolase from Clonostachys rosea – has been assessed for the cis-isomer as well. Our results showed that both isomers can act as functional analogues with respect to xenoestrogenic activity, and several cis-ZEN metabolites with high biological potential have been identified. On the contrary, in spite of the high degree of structural analogy, the cis isomer showed a pattern of interaction with the degrading enzyme in stark contrast with that observed for trans-ZEN. For these reasons, the outcomes presented herein strongly support the inclusion of cis-ZEN in further studies of occurrence, metabolism and bioactivity assessment, and suggest the need for a dedicated handling for the cis isomer in risk assessment studies.     

The potential health challenges of TiO2 nanomaterials

Titanium dioxide (TiO₂) nanomaterials (NMs) have found widespread applications owing to their attractive physical and chemical properties. As a result, the potential adverse impacts of nano‐TiO₂ exposure on humans have become a matter of concern. This review presents the state‐of‐the‐art advances on the investigations of the adverse effects of NMs, including the potential exposure routes of nano‐TiO₂ (e.g. respiratory system, skin absorption and digestive system), the physico‐chemical characterizations of nano‐TiO₂ (e.g. crystal structure, shape,size, zeta potential, treatment media, aggregation and agglomeration tendency, surface characteristics and coatings), risk evaluation of nanotoxicity (e.g. cytotoxicity, ecotoxicity, phototoxicity, and phytotoxicity) and potential mechanisms of adverse effects (e.g. generation of reactive oxygen species, oxidative stress and organelle dysfunction). The review aims to facilitate scientific assessments of health risks to nano‐TiO₂, which would guide the safe applications of NMs in our daily life. Copyright © 2015 John Wiley & Sons, Ltd.     

抗凝血活性海洋硫酸多糖HP1-1的结构研究

目的 对抗凝血活性海洋硫酸多糖HP1-1的结构进行研究。方法 通过高效液相色谱(HPLC)、高效凝胶渗透色谱(HPGPC)、傅里叶变换红外光谱(IR)以及气质联用色谱(GC-MS)和核磁共振波谱(NMR)方法,对抗凝血活性海洋硫酸多糖HP1-1的结构进行解析。结果 海洋硫酸多糖HP1-1的分子量为297 kDa,总糖和硫酸基含量分别为78.1%和12.3%;HP1-1主要由葡萄糖组成,含有少量半乳糖、阿拉伯糖和甘露糖;HP1-1糖链中含有→4)-Glcp-(1→、→3)-Glcp-(1→、→3,4)-Glcp-(1→、→4)-Arap-(1→、→3,4)-Galp-(1→和→3)-Galp-(1→,硫酸基位于→4)-Glcp-(1→的C-3位和→3)-Galp-(1→的C-4位。 结论 海洋多糖HP1-1是主要由葡萄糖组成的硫酸多糖,含有多种糖基连接方式,为独特结构序列的新颖海洋硫酸甘露阿拉伯半乳葡聚糖。     

Hemodialysis improves myocardial interstitial edema and left ventricular diastolic function in patients with end-stage renal disease: noninvasive assessment by ultrasonic tissue characterization

Congestive heart failure is the most common cause of mortality in patients with end-stage renal disease (ESRD). Ultrasonic tissue characterization with integrated backscatter offers a promising method for the noninvasive assessment of regional myocardial contractile performance and fibrosis. The aim of this study was to investigate the effect of hemodialysis (HD) on myocardial tissue characterization and left ventricular function in ESRD patients. We examined 26 patients with ESRD undergoing routine HD (age 63 ± 12 years, duration of HD 9.2 ± 3.2 years) and 30 patients with essential hypertension (HT; 60 ± 10 years). Routine echocardiographic parameters and the cyclic variation of ultrasonic integrated backscatter of the ventricular septum (CV-IBS) were measured. Left ventricular mass index was significantly larger in patients with ESRD than in those with HT (217 ± 56 vs 146 ± 45 g/m², P < 0.05). The indices for left ventricular diastolic function (E/A, the ratio of left ventricular peak early to late diastolic filling velocity; DT, the deceleration time of the early diastolic filling) and CV-IBS had deteriorated significantly in patients with ESRD before HD compared with those with HT (E/A, 0.6 ± 0.2 vs 0.9 ± 0.3, P < 0.05; DT, 228 ± 23 vs 184 ± 19 ms, P < 0.05; CV-IBS, 9.0 ± 1.3 vs 12.4 ± 0.9 dB, P < 0.05), possibly reflecting interstitial fibrosis. In patients with ESRD, HD reduced calculated left ventricular mass index by 19% (before HD, 217 ± 56 vs immediately after HD, 176 ± 45 g/m², P < 0.05) and CV-IBS by 19% (9.0 ± 1.3 vs 7.3 ± 1.1 dB, P < 0.05), that possibly reflected improvement of interstitial edema. HD also significantly improved indices for left ventricular diastolic function (E/A, 0.6 ± 0.2 vs 0.9 ± 0.2, P < 0.05; DT, 228 ± 23 vs 188 ± 21 ms, P < 0.05). HD improves myocardial interstitial edema and left ventricular diastolic function in patients with ESRD. Noninvasive assessment of ultrasonic tissue characterization is useful in defining the pathophysiological changes of ventricular myocardium in patients with ESRD. Received: December 17, 2001 / Accepted: April 19, 2002 Correspondence to O. Hirono     

A coxsackievirus B5‐associated aseptic meningitis outbreak in Shandong Province,China in 2009

In 2009, a major outbreak of aseptic meningitis was noted in Linyi city, Shandong province, China. From June to September 2009, a total of 2,104 cases were involved in this outbreak, and 98.6% of patients were <16 years of age. To determine the pathogen of the outbreak, 42 cerebrospinal fluid specimens collected from aseptic meningitis cases were tested for cell culture, and 17 (40.5%) enteroviruses were isolated and identified as Coxsackievirus B5 (CVB5). Homologous comparison indicated that these isolates had 0–7.7% nucleotide divergence with each other. Phylogenetic reconstruction showed global CVB5 could be separated into four genogroups, and all Linyi CVB5 isolates belonged to the genogroup C which had been circulating for recent 27 years in Asia and Europe. Interestingly, two distinct lineages were observed for the 17 isolates in the phylogenetic tree, indicating that at least two different transmission chains of CVB5 were responsible for this outbreak. This study showed that CVB5‐associated aseptic meningitis is an emerging concern in China. J. Med. Virol. 85:483–489, 2013. © 2012 Wiley Periodicals, Inc.     

Time-frequency characterization of atrial fibrillation from surface ECG based on Hilbert-Huang transform

In this paper, based on Hilbert-Huang transform (HHT), we develop a new non-invasive time-frequency analysis method to characterize the dynamic behaviour of atrial fibrillation (AF) from surface ECG. We first extract f waves from single-lead ECG records of AF patients using PCA analysis. To capture the non-stationary behaviours of AF signals at different time scales, we use HHT to find the Hilbert spectrum and instantaneous frequency (IF) distribution of residual signals from principal component analysis. Two important feature variables, namely mean IF (mIF) and index of frequency stability over time (IS), are derived from the IF distribution, and in combination will be able to effectively discriminate two different AF types: self-terminating and non-terminating termination. The proposed AF signal decomposition and analysis method will help us efficiently differentiate individual AF patients, advance our understanding of AF mechanisms, and provide useful guidelines for improving administration of AF patients, especially paroxysmal AF.     

Antimicrobial and physicochemical characterization of endodontic sealers after exposure to chlorhexidine digluconate

ObjectivesAssess the antibacterial, physical and chemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) in contact with 2% chlorhexidine digluconate (CHX) used as final irrigant prior to root canal obturation.MethodsThe antimicrobial properties were investigated by direct contact tests for planktonic and biofilm growth of E. faecalis, S. mutans, S.epidermidis and S.aureus in vitro. The setting time, wettability, microhardness and surface roughness were also assessed. The sealers were studied in no contact, 1-minute (short-term) and continuous contact (long-term) with CHX. Chemical characterization of sealers was performed by scanning electron microscopy, X-ray diffraction analysis and Fourier-transform infrared spectroscopy after CHX or saline used as the last irrigant in an ex vivo tooth model and in endo training blocks.ResultsCHX increased the antibacterial activity of all the sealers investigated against planktonic bacteria and biofilms with PCS exerting the highest antimicrobial activity with and without the presence of CHX. The setting of AH Plus and BioRoot RCS was retarded, while for PCS accelerated in the presence of CHX. AH Plus and PCS were more hydrophilic after contact with CHX, whilst BioRoot RCS was hydrophobic in a time-dependent manner. The microhardness of sealers was compromised and the surface roughness increased after CHX exposure for AH Plus and BioRoot RCS, and decreased for PCS. CHX did not affect the sealers’ chemistry, but PCS that exhibited two extra phases.SignificanceCHX improved the antibacterial efficacy of endodontic sealers but further evidence is needed to confirm its suitability as a final irrigant prior to root canal obturation.     

血液环境下Biodentine与MTA的颜色稳定性研究

目的比较牙体牙髓治疗中常用的骨水泥材料Biodentine与三氧化矿物凝聚体(mineral trioxide aggregrate,MTA)在与血液接触条件下的颜色稳定性,并探讨其可能的变色原因。方法制备直径5 mm、高3 mm的Biodentine和MTA圆盘,将每种材料的24个圆盘随机分配到去离子水组和脱纤维羊血组中,浸泡1 d和7 d后进行后续检测。进行各类检测的3个时间点为:圆盘固化脱模后即刻、浸泡1 d和7 d后。检测指标如下:在同样光照环境下对圆盘进行拍照,直观比较两种材料的颜色变化;采用比色仪检测两种材料的色度;借助扫描电镜观察两种材料的表面形态;使用X射线能谱仪测量两种材料各元素含量。结果肉眼观察到与脱膜后即刻相比,在脱纤维羊血组浸泡1 d后仅MTA在明暗度上发生改变,脱纤维羊血组浸泡7 d后Biodentine与MTA颜色均加深变红,但MTA暗度明显增加。比色仪结果显示脱纤维羊血组MTA的7 d色差值ΔE(21.257±0.955)大于Biodentine的7 dΔE(5.833±0.501)(t=24.781,P<0.001);MTA材料自身变色随着与血液接触时间延长而加深,其7 dΔE与1 dΔE(6.233±0.888)相比,差异具有统计学意义(t=19.956,P<0.001);而Biodentine材料自身变色随时间延长则无统计学意义[7 dΔE与1 dΔE(6.790±0.831)相比,t=1.707,P=0.163]。扫描电镜结果表明:用脱纤维羊血浸泡7 d后,MTA表面孔隙率大于Biodentine,且MTA的晶体边缘相较Biodentine也更为圆钝。X射线能谱仪检测显示:在脱纤维羊血组浸泡7 d后MTA中氧元素含量下降、铋元素含量上升;与此同时Biodentine因阻射能力低未被检测出锆元素,但其他元素含量稳定。结论Biodentine在与血液接触条件下的颜色稳定性优于MTA,这主要与Biodentine表面孔隙率小、阻射剂成分稳定有关。