Ensemble noise and current relaxation analysis of K+ current in single isolated salivary acinar cells from rat

The K⁺ channel in rat parotid gland acinar cells were investigated by ensemble current noise analysis in single isolated cells employing the giga-seal whole cell current recording mode. Sets of 20–40 identical de- and hyperpolarization voltage steps were applied and the resultant current records were processed by computer to obtain the mean and the variance of the current. The time-course of the mean current could be fitted by the sum of two exponentials, suggesting a 3-state model. The simplest plausible hypothesis is a model with one open and two closed states. Assuming this model, the relationship between the variance (₂) and the mean current (I) could be fitted by the function ₂/I=i–I/N. The estimated single channeli/V-relations were similar to those taken from single channel current recordings, and the size of the population of channels per cell (N) was 76±26 (n=12). The validity of the model was tested by a successful simulation of the time-course of the variance.     

Surveillance of resistance in bacteria causing community-acquired respiratory tract infections

Bacterial resistance to antibiotics in community-acquired respiratory tract infections is a serious problem and is increasing in prevalence world-wide at an alarming rate. Streptococcus pneumoniae , one of the main organisms implicated in respiratory tract infections, has developed multiple resistance mechanisms to combat the effects of most commonly used classes of antibiotics, particularly the β -lactams (penicillin, aminopenicillins and cephalosporins) and macrolides. Furthermore, multidrug-resistant strains of S. pneumoniae have spread to all regions of the world, often via resistant genetic clones. A similar spread of resistance has been reported for other major respiratory tract pathogens, including Haemophilus influenzae , Moraxella catarrhalis and Streptococcus pyogenes . To develop and support resistance control strategies it is imperative to obtain accurate data on the prevalence, geographic distribution and antibiotic susceptibility of respiratory tract pathogens and how this relates to antibiotic prescribing patterns. In recent years, significant progress has been made in developing longitudinal national and international surveillance programs to monitor antibiotic resistance, such that the prevalence of resistance and underlying trends over time are now well documented for most parts of Europe, and many parts of Asia and the Americas. However, resistance surveillance data from parts of the developing world (regions of Central America, Africa, Asia and Central/Eastern Europe) remain poor. The quantity and quality of surveillance data is very heterogeneous; thus there is a clear need to standardize or validate the data collection, analysis and interpretative criteria used across studies. If disseminated effectively these data can be used to guide empiric antibiotic therapy, and to support—and monitor the impact of—interventions on antibiotic resistance.     

Electrical properties of metallic electrodes

The series equivalent resistance R and capacitance C of metal/saline electrode/electrolyte interfaces were measured as a function of frequency (100 Hz–20k Hz) and current density (0·25 to 1000 A m⁻²) for eight typical electrode metals. For each of the metals tested, R decreased and C increased as the current density was increased above a critical value (with the exception of silver and MP35N at frequencies above 1 kHz for which R increased and C decreased slightly). With the exception of copper, the current density linearity limit (for 10 per cent decrease in R or 10 per cent increase in C) increased with increasing frequency and, in most cases, the current density linearity limit for 10 per cent increase in C was slightly less than that for 10 per cent decrease in R. Among the metals tested, copper and aluminium had the lowest current carrying capability and rhodium had the highest current-carrying capability. The current carrying capabilities of 316 SS, platinum, silver and MP35N, were intermediate and similar. With increasing current density, an increase in the electrode/electrolyte capacitance was the most sensitive indicator of the current-carrying linearity limit.     

Providing Interdisciplinary Geriatric Team Care: What Does It Really Take?

We concur with Speer and Schneider's arguments (2003 ; this issue) that more psychologists should offer mental health services to older adults and that the primary care system is a good focus of such efforts. Three issues deserve more prominence in their review. First, their argument that older adults are averse to mental health services seems incorrect, given research indicating that older adults prefer psychotherapy to medication for treatment of depression. Second, psychologists working in primary care need to be aware of new Current Procedural Terminology (CPT) codes that allow documentation of psychological work in medical settings. Third, Speer and Schneider allude to interdisciplinary team functioning, but provide little information about models of team care or issues in developing a well-functioning interdisciplinary team; this commentary expands on those topics.     

Measurement of current spread from microelectrodes when stimulating within the nervous system

Summary Tungsten stimulating microelectrodes have been tested in monopolar, bipolar and concentric configurations for the extent to which unwanted current spread occurred. Current spread from monopolar electrodes in close conformity with the predictions of the inverse square law, both in vitro and in vivo. The bipolar and concentric configurations, tested only in vitro, had current-spread characteristics which did not follow the inverse square law so closely. The bipolar configuration gave little reduction in spread, compared with a monopolar electrode, but the concentric configuration did reduce the extent of stimulus spread. The extent of spread depends greatly upon a number of experimental variables, including the dimensions of the microelectrode tip. For studies requiring precise localization, with low stimulus currents, it is advisable to determine the inverse square law constant for each experimental situation. For more generalized stimulation purposes within the mammalian C.N.S., employing monopolar microelectrodes of moderate tip size, brief pulses of 10 A can be expected to stimulate myelinated axons within about 0.15 mm of the tip, and 100 A will stimulate within a radius of about 0.5 mm.The work was all done while E.V.B. was on Industrial Training leave from the North-East Polytechnic, Romford Road, London E. 15     

Localisation of myocardial ischaemia from the magnetocardiogram using current density reconstruction method: computer simulation study

A computer simulation study is performed to investigate the method of current density reconstruction to localise myocardial ischaemia. A computer model of the entire human heart is used to simulate the excitation and repolarisation process in eight topographically different cases of myocardial ischaemia. The associated magnetocardiogram is calculated at 37 positions of the KRENIKON^* biomagnetic measurement equipment. The method of current density reconstruction is applied at the S-point (the last discemible deviation from the ST-segment at the end of the QRS-complex) of the MCG to find characteristics of the myocardial ischaemia simulated by the model. The results show that it is possible to determine the location of the ischaemia. The current density distribution may be interpreted physiologically in terms of the so-called ‘injury current’. This indicates that magnetocardiography might be a suitable method for noninvasive ischaemia diagnosis, and further investigations of the current density reconstruction method for the injury current should be performed on patients with ischaemic heart disease.     

2005-2019年理塘县法定传染病疫情分析

目的了解理塘县近15年法定传染病疫情形势及流行特征,为政府制定防控措施提供科学依据。方法对2005—2019年理塘县法定传染病疫情进行描述性流行病学分析。采用ArcGIS 10.3软件绘制各乡镇发病情况分布图,SPSS 21.0软件进行χ²检验、趋势性χ²检验。结果2005—2019年理塘县共计报告甲乙丙类传染病21种6154例,年均发病率为644.33/10万,发病呈上升趋势。死亡37例,年均死亡率3.87/10万,病死率0.60%。呼吸道传染病发病最高(341.12/10万);发病前3位的病种为肺结核(271.91/10万)、乙肝(103.24/10万)及包虫病(67.22/10万);肺结核、其他感染性腹泻病、艾滋病/HIV、梅毒发病呈上升趋势。3月、9月分别出现1次发病高峰;20~29岁、30~39岁和10~19岁组发病居前3位;男女性别比为1.24∶1;发病以农民、牧民及学生为主。结论2005-2019年理塘县法定传染病发病率较高且呈上升趋势,应针对高发传染病、上升趋势明显的传染病、重点人群进行分析研究,采取针对性措施控制疫情。     

成都市家庭医生服务现状的定性研究

目的 本研究针对成都市基层医疗卫生服务机构,调查分析了家庭医生服务开展现况、存在的问题,以及家医服务平台的建设情况并提出了改进建议。方法 本研究共抽取了成都市六个基层社区卫生服务机构,对每家机构的1名管理人员和1个家庭医生团队分别进行深入访谈和专题小组访谈,调查时间为2020年12月—2021年2月。结果 成都市双向转诊取得一定成效,但下转难情况依然突出;有偿签约效果不好,居民就诊观念需转变;基层卫生技术人员不足,家医服务增加了日常工作量;家医信息化平台存在诸多问题,功能亟需改善;家医的绩效考核制度有一定激励作用,但仍需完善;基层卫生投入不足,家医政策落地难。结论 规范分级诊疗秩序,畅通双向转诊通道;加强官方媒体宣传力度,转变居民就诊观念;提升基层职业吸引力,培养优质人才;加强信息化建设,完善家庭医生信息化服务平台;健全家庭医生绩效考核制度,调动工作积极性;完善家医配套政策与措施,强化基层机构服务能力。     

医防融合背景下我国基层医疗卫生机构医防工作现状及认知调查

目的 通过调查我国5省基层卫生人员医防工作的参与情况与对开展医防融合工作的认知现状, 探讨目前基层医防融合工作存在的问题,为促进基层医疗卫生机构医防融合工作提供参考依据。方法 采用多阶段分层抽样,根据地域方位差异分别抽取四川、贵州、江西、江苏和广东5个省,再依据经济状况每省选取3个区县,共15个区县的乡镇卫生院和社区卫生服务中心(站)的卫生人员(6 439名)进行问卷调查与访谈, 对调查数据进行描述并对医防融合工作参与情况与认知现状进行检验。结果 从事公共卫生工作的958名卫生人员中,仅有292人(30.5%)同时参与公共卫生服务与医疗服务,有615人(64.2%)只参与公共卫生服务; 51.7%的公共卫生工作人员以独立公共卫生服务的方式参与基本卫生服务。从事公共卫生工作的卫生人员主要以护理学和临床医学专业为主,仅15.6%的人员具有预防医学专业背景。从事临床医疗工作的1 964名人员中,1 464人(74.5%)医疗服务与公卫服务均参与,但对基本公共卫生服务的投入时间相对较少。不同岗位的卫生人员参与医防工作的情况不同(=2 208.874,P<0.001)。结论 基层临床医疗工作与公共卫生工作机制相对独立。公共卫生工作人员因缺乏疾病诊断治疗能力或无处方权而不能很好地参与到临床医疗工作中; 临床医疗工作人员因缺乏公共卫生知识和技能对公共卫生服务的参与受限。 建议整合医防融合服务机制,打造基层整合型服务; 培养基层医防复合型人才,加大全科医生培养力度。