多功能粘结剂和复合树脂修复牙体缺损86例观察

本文将多功能粘结剂和复合树脂应用于86例牙体缺损的修复并进行术后两年的随访复查,成功率达92.3％,依据病损的不同类型统计学上有显著差异。     

Resazurin metabolism assay for root canal disinfectant evaluation on dual-species biofilms

Introduction

Endodontic infections are caused by polymicrobial biofilms. Therefore, novel root canal disinfectants should be evaluated not only on single-species biofilms but also on dual- or mixed-species biofilms. A simple, high-throughput assay is urgently needed for this. In this study, the application of the resazurin metabolism assay was investigated for the evaluation of a root canal disinfectant on dual-species biofilms.

Methods

Enterococcus faecalis with or without Streptococcus mutans in biofilms were formed in an active attachment biofilm model for 24 hours. Subsequently, the biofilms were treated with various concentrations of NaOCl for 1 minute. After resazurin metabolism by both organisms was confirmed, treatment efficacies using 0.0016% resazurin were evaluated.

Results

During NaOCl treatments, resazurin metabolism displays a clear dose response, not only in single-species E. faecalis (or S. mutans) biofilms but also in dual-species biofilms. Notably, the assay revealed that the resistance of dual-species biofilms to NaOCl was 30-fold higher than in single-species E. faecalis biofilms. Viability counts on a selected NaOCl treatment (0.004%) confirmed this result and showed the increased resistance of E. faecalis in dual-species biofilms.

Conclusions

Clearly, the high-throughput and low cost resazurin metabolism assay has a great potential for testing novel root canal antimicrobial agents in mixed-species biofilms.     

Intermediate filaments in the medial rectus muscles in patients with concomitant exotropia

International Ophthalmology - Distribution of intermediate filament (IF) proteins in normal extraocular muscles (EOMs) showed that the EOMs differ significantly from the other muscles in the body...     

电刺激小脑顶核对持续局灶性脑缺血时钙蛋白酶活性的影响

目的观察电刺激小脑顶核(FN)对持续局灶性脑缺血钙蛋白酶活性的影响,以阐明其神经保护作用机制。方法健康雄性Wistar大鼠,随机分为假手术组(PO)、FN刺激假手术组(PO-FN)、持续缺血组(PI)及持续缺血-FN刺激组(PI-FN),后两组又分为缺血1,3,6,12及24h组。建立大鼠电刺激FN及持续局灶性脑缺血模型,应用Western印迹半定量各组缺血核心区Mr=150000FBDP含量(表示钙蛋白酶活性),并应用尼氏体染色对缺血核心区神经元数量及形态进行分级评分。结果PO组及PO-FN组钙蛋白酶活性相似(P>0.05),处于低水平。PI组钙蛋白酶活性从缺血1h犤(3670±600)A/μg总蛋白犦开始即显著增高(t=6.338,P<0.001),以后随着缺血时间延长,钙蛋白酶活性不断增高,直至缺血24h犤(9180±360)A/μg总蛋白犦仍有持续增高趋势(缺血12,24h,t=14.673,16.632,P<0.001)。PI-FN组随着缺血时间的延长,钙蛋白酶活性从缺血1h犤(2510±460)A/μg总蛋白犦也开始增高,以后随着缺血时间延长,钙蛋白酶活性不断增高,但各时点组与其相应PI组相比,其增高程度明显减低,差别具有显著意义(缺血1,24h,t=1.875,2.134,P<0.05)。PO组及PO-FN组神经元形态及数量正常,评分均为0分。PI组从缺血1h(0.8±0.3)开始,神经元形态、数量即出现轻度改变,其评分增高(z=2.443,P<0.01),以     

以肾浊辨识理论认识阿尔茨海默病的诊断与治疗

目的以中医肾浊辨识理论认识阿尔茨海默病的相关特征.方法从病理变化,发病机制,临床表现等几个方面对肾浊与阿尔茨海默病的关系进行分析.结果现代神经病理检查发现阿尔茨海默病患者大脑皮质蒌缩,脑回变平,脑沟增宽,脑室扩大,脑重量减轻,皮质神经细胞有不同程度的减少,这些变化是中医肾精不足的表现.阿尔茨海默病造成神经元丧失的主要机制是氧自由基作用于神经细胞元,引起Ca2+内流增加,中医理论视氧自由基为"肾浊".阿尔茨海默病患者肾精不足,心失所养,加之肾浊上扰,心神失常,投射于脑,影响脑的功能,故产生近记忆障碍常为阿尔茨海默病首发症状.结论对阿尔茨海默病的中医治疗,在注重补肾填精的同时,更要注重泄肾浊,针对肾浊运用祛疾泄浊,除湿化疾之法.     

Relationship between effort–reward imbalance and hair cortisol concentration in female kindergarten teachers

Objective

The present study aims to investigate the relationship between effort–reward imbalance and hair cortisol concentration among teachers to examine whether hair cortisol can be a biomarker of chronic work stress.

Methods

Hair samples were collected from 39 female teachers from three kindergartens. Cortisol was extracted from the hair samples with methanol, and cortisol concentrations were measured with high performance liquid chromatography–tandem mass spectrometry. Work stress was measured using the effort–reward imbalance scale.

Results

The ratio of effort to reward showed significantly positive association with hair cortisol concentration.

Conclusion

The cortisol concentration in the system increases with the effort–reward imbalance. Measurement of hair cortisol can become a useful biomarker of chronic work stress.     

Clinical features and surgical outcomes of intramedullary schwannomas

Object

Intramedullary schwannomas are exceedingly rare. Most previous studies are case reports with an associated literature review. The aim of this study was to discuss the clinical features and the outcomes of microsurgery for these rare lesions.

Methods

The authors retrospectively reviewed the data of twenty patients with intramedullary schwannomas. All patients had performed preoperative and postoperative magnetic resonance imaging (MRI) and underwent microsurgery. The diagnosis of intramedullary schwannomas was based on radiological and pathological criteria. Modified McCormick classification was applied to assess neurological function.

Results

There were 15 males and five females with a mean age of 44.7 years. Ten tumors were located in the cervical cord, five in the thoracic cord, two in the cervicothoracic cord, two in the thoracolumbar cord and one in the conus medullaris. Patients presented with nonspecific symptoms and the mean duration of symptoms was 37.4 months. Intraoperatively, the tumor was connected to the dorsal rootlet in four cases. Gross total resection (GTR) of the tumor with a well-demarcated dissection plane was achieved in 16 cases, and subtotal resection (STR) was achieved in four cases. No patients received postoperative radiotherapy. During a mean follow-up period of 67.9 months, no recurrence or regrowth of the residual tumors was observed on MRI. Ninety percent of patients experienced an improvement in the McCormick grade and 10 % of patients maintained their preoperative status.

Conclusions

Intramedullary schwannomas are benign but clinically progressive lesions. The accurate diagnosis depends on pathology. For symptomatic patients, early surgery should be performed before neurological deficits deteriorate. When GTR cannot be achieved, STR of the tumor for decompression is advised. Postoperative radiotherapy is not recommended for these benign tumors. A good clinical outcome after GTR or STR can be expected.