铬对低硒状态所致心肌损伤保护机理研究

目的 研究铬对低硒状态所致心肌损伤保护作用，探讨其保护机理。方法 克山病病区粮喂养Wistar大鼠复制低硒动物模型，加铬加硒作为干预因素，观察其生长发育状况；描记心电图；玻璃微电极法测心肌细胞电生理；荧光偏振法测心肌细胞线粒体膜流动性；低温顺磁共振技术测心、肝自由基含量；生化法测血、心、肝GSH-Px及SOD活性；放射免疫法测心肌环磷酸腺苷和甲状腺激素；透射电镜观察心肌超微结构变化。结果 低硒饲料喂养动物生长延迟；心电图及心肌电生理QRS时限、Q-T间期及APD50、APD50延长；心肌细胞膜流动性降低；心肝自由基水平升高、抗氧化酶类GSH-Px及SOD活性降低；甲状腺激素T3、T4及心肌cAMP降低；心肌超微结构显示心肌损伤。铬则可改善低硒动物营养状况，恢复心肌组织生理病理学改变。结论 铬对低硒状态所致心肌损伤具有保护作用，逆转QRS时限、Q-T闻期和APD的改变；提高心肌细胞膜流动性；增强抗氧化酶活性，降低自由基水平及调整甲状腺激素和心肌cAMP代谢则是铬抗低硒心肌损伤的重要作用机制。     

Skeletal class II malocclusion caused by mouth breathing in a pediatric patient undergoing treatment by interceptive guidance of occlusion

A 7-year 10-month-old boy was evaluated for mouth breathing and snoring habits. Examination revealed soft convex tissues, maxillary protrusion, mandibular retrusion, and a class II sagittal osteofascial pattern. The patient failed a water holding test. He was clinically diagnosed with skeletal class II malocclusion caused by mouth breathing. Under interceptive guidance of occlusion (iGo), the malocclusion improved with fixed maxillary expansion using functional appliances and interventional treatment of mouth breathing by lip closure exercises. These treatments enabled the patient to gradually return to nasal breathing and guided him to develop physiological occlusion for a coordinated jaw-to-jaw relation. At the 5-year 2-month post-correction follow-up visit (at the age of 13 years), the patient had stable occlusion, a coordinated osteofascial pattern, and normal dentition, periodontium, and temporomandibular joints.     

Impact of COVID-19 pandemic on radiographers in the Republic of Cyprus. A questionnaire survey

IntroductionImaging is essential for the initial diagnosis and monitoring of the novel coronavirus, which emerged in Wuhan, China. This study aims to assess the insight of radiographers on how the COVID-19 pandemic has affected their work routine and if protective measures are applied.MethodA prospective observational study was conducted among radiographers registered in the Cyprus Society of Registered Radiologic Technologists & Radiation Therapy Technologists. A questionnaire composed of 28 multiple choice questions was utilised, and the data analysis was performed using SPSS software with the statistical significance assumed as p-value < 0.05.ResultsOut of 350 registered radiographers, 101 responses were received. The results showed that there are statistically significant differences regarding the working hours, the feeling of stress, the work effectiveness, the average examination time, the presence of a protocol used among the different workplaces of the participants; a private radiology centre, a private hospital or a public hospital, with a p-value 0.0022, 0.015, 0.027, 0.001, 0.0001 respectively. Also, statistically significant differences were observed in the decontamination methods used for equipment (p-value 0.007), for air (p-value 0.04) and when decontamination takes place (p-value 0.00032) among the different workplaces of the participants. Nonetheless, the majority of radiographers believe that their workplace is sufficiently provided with PPE, cleaning supplies, equipment, and with cleaning personnel and are optimistic regarding the adequacy of these provisions in the next three months.ConclusionThis study showed that in the Republic of Cyprus, there are protocols regarding protective measures against COVID-19, and the radiographers are adequately trained on how to face an infectious disease outbreak. However, work is needed in order to develop protocols that reassure the safety of patients and medical personnel while managing the excess workload effectively.Implications for practiceThis study indicates the importance of applying protective measures and protocols in the radiology departments in order to minimise the spread of the virus.     

Rapid review of virus risk communication interventions: Directions for COVID-19

ObjectiveIn response to COVID-19, we conducted a rapid review of risk communication interventions to mitigate risk from viruses to determine if such interventions are efficacious.MethodsWe searched for risk communication interventions in four databases: Medline, PsycInfo, the ProQuest Coronavirus Research Database, and CENTRAL. The search produced 1572 articles. Thirty-one articles were included in the final review.ResultsResults showed risk communication interventions can produce cognitive and behavior changes around viruses. Results were more consistently positive for interventions focused on HIV/AIDS as compared to influenza. There was no consistent best intervention approach when comparing peer health, audio/visual, and intensive multi-media interventions. Tailoring risk communication toward a target population, in comparison to not tailoring, was related to better outcomes.ConclusionThe results suggest that risk communication interventions can be efficacious at reducing risk from viruses. They also highlight the complexity of risk communication interventions. Additional research is needed to understand the mechanisms that lead risk communication to reduce risk from viruses.Practical valueResults support risk communication interventions to reduce risk from viruses.     

Twin-block矫治器治疗安氏Ⅱ类骨性错后的软、硬组织变化

目的:探讨Twin-block矫治器早期矫治对安氏Ⅱ类骨性错患者软、硬组织的影响。方法:前瞻性选择60例安氏Ⅱ类骨性错患者为研究对象,应用随机数字表法将患者分为2组,每组各30例。实验组采用Twin-block联合直丝矫治器治疗,对照组采用直丝矫治器治疗。观察2组矫治前、矫治后12个月、36个月硬组织指标（SNA、SNB、ANB、U1-NA夹角、U1-NA距离、L1-NB距离、L1-NB夹角、U1-L1夹角）和软组织测量指标[UL-U1、LL-L1、覆盖（over jet）、覆（overbite）、上唇突点至E 线的垂直距离（E-upper-lip）、下唇突点至E 线的垂直距离（E-lower-lip）、颏沟倾角、颏软组织厚度]的变化。采用SPSS 25.0软件包对数据进行统计学分析。结果:实验组矫治后12个月、36个月U1-NA、U1-NA、L1-NB、L1-NB、覆盖、覆、E-upper-lip、E-lower-lip显著小于对照组（P<0.05）,U1-L1、鼻唇角、颏沟倾角、颏软组织厚度显著大于对照组（P<0.05）。结论:Twin-block联合直丝矫治器可显著改善安氏Ⅱ类骨性错患者口颌以及面部软、硬组织关系,远期效果良好。     

一次性气管切开集痰保湿防护罩在气管切开术后患者气道湿化中的应用效果

目的 评价一次性气管切开集痰保湿防护罩在气管切开术后非机械通气患者气道湿化中的应用效果。方法 选取气管切开术后非机械通气患者48例,随机将其分入传统组(n=16)、实验组(n=16)和对照组(n=16)。传统组采用2层湿纱布覆盖气管切开导管口进行湿化,实验组使用防护罩湿化,对照组使用人工鼻湿化。比较3组患者呼吸功能、气道温度和湿度、Ⅲ度黏痰以及湿化不足并发症的发生情况。结果 3组患者血氧饱和度、动脉血氧分压和动脉血二氧化碳分压在时间效应、组间效应及交互效应上比较,差异均无统计学意义(P＞0.05)。干预7 d后,实验组吸气温度高于对照组(P＜0.05),吸气湿度低于对照组(P＜0.05),且均高于传统组(P＜0.05);3组呼气温度比较,差异无统计学意义(P＞0.05),实验组与对照组呼气湿度差异无统计学意义(P＞0.05),但2组均高于传统组(P＜0.001);3组的痰液黏稠度比较,差异有统计学意义(χ²=6.400,P=0.041),3组气道出血及肺部感染发生率比较,差异无统计学意义(χ²=3.091,P=0.230;χ²=1.948,P=0.763)。结论 一次性气管切开集痰保湿防护罩能提升气管切开术后患者气道温度和湿度,有效湿化气道。     

The effect of light-emitting diode and laser on mandibular growth in rats

Objective:To evaluate the effect of a light-emitting diode (LED) and/or low-level laser (LLL) with or without the use of anterior bite jumping appliances (also known as functional appliances [FAs]) on mandibular growth in rats.Materials and Methods:Thirty-six 8-week-old male Sprague-Dawley rats weighing 200 g were obtained from Charles River Canada (St. Constant, QC, Canada) and were divided into six groups of six animals each. Groups were as follows: group 1: LLL; group 2: LLL + FA; group 3: LED; group 4: LED + FA; group 5: FA; and group 6: control (no treatment). Mandibular growth was evaluated by histomorphometric and micro computed tomographic (microCT) analyses.Results:The LED and LED + FA groups showed an increase in all condylar tissue parameters compared with other groups.Conclusion:The LED-treated groups showed more mandibular growth stimulation compared with the laser groups.     

儿童早期肌功能训练与错（牙合）畸形预防矫治

现代儿童错(牙合)畸形的矫治更强调早期预防与阻断,矫正理念是“咬合发育管理”,治疗儿童从出生后到恒牙替换萌出结束整个过程的咬合发育不良。儿童早期肌功能训练及错(牙合)畸形预防矫治应用“Muscle?Win”理论,早期预防与阻断错(牙合)畸形的发生,以期最终降低儿童错(牙合)畸形的发生率与严重程度。早期肌功能训练及错(牙合)畸形预防矫治器是一种功能矫治器,其特点是：1）其重建了上下咬合关系,控制上下颌骨的位置及生长;2）矫治器功能结构能训练舌肌、唇颊肌及颏肌的功能和矫正口呼吸习惯;3）恒牙萌出诱导槽能引导排列新萌出的恒牙;4）矫治器能恢复上下牙弓的形态与宽度。临床佩戴矫治器,能训练儿童口腔功能,去除口腔不良习惯,引导恒牙萌出,并对Ⅱ/Ⅲ类错(牙合)畸形和轻中度牙弓发育不良有矫治效果。儿童早期肌功能训练及错(牙合)畸形预防矫治有局限性,正确选择临床适应证及使用时机是保证疗效、防止临床过度治疗的关键。作为儿童错(牙合)畸形早期功能矫治的有益探索,早期肌功能训练及错(牙合)畸形预防矫治器正成为“咬合发育管理”临床技术体系的有机组成,并得到儿童口腔医学及口腔正畸学医生越来越多的重视。