无抗凝连续性肾脏替代治疗体外循环装置使用时间影响因素的研究

目的探讨影响无抗凝连续性肾脏替代治疗(CRRT)体外循环装置使用时间的主要影响因素,为合理的无抗凝CRRT护理风险评估提供依据。方法对2015年7月至2018年7月首次行无抗凝CRRT合并高危出血风险的257例急慢性肾衰竭患者进行回顾性分析。结果无抗凝CRRT治疗中体外循环装置发生衰竭125例(48.64%),CRRT体外循环装置使用时间为(248.51±87.56)min。多因素Cox比例风险回归模型分析显示,4个独立影响因素与体外循环装置使用时间显著相关,分别为:治疗中血流量不畅停泵次数(HR=1.572,95%CI=1.373～1.801),静脉壶栓塞容积比(HR=1.022,95%CI=1.014～1.030),红细胞压积(HR=1.037,95%CI=1.007～1.068),CRRT治疗剂量(HR=1.336,95%CI=1.007～1.772)。结论治疗中血流量不畅停泵次数、高静脉壶栓塞容积比、高红细胞压积、高CRRT剂量是影响无抗凝CRRT体外循环装置使用时间的独立危险因素;治疗中施行周期性生理盐水冲洗并不能有效延长体外循环装置的使用时间。临床工作者应针对相关危险因素有针对性地制定干预措施,进而最大限度地降低体外循环装置衰竭的发生率,延长装置使用时间,保障医疗护理安全。     

Should the Placement of Carbon Monoxide (CO) Detectors be Influenced by CO’s Weight Relative to Air?

Background

Numerous states and localities have recently passed legislation mandating the installation and use of residential carbon monoxide (CO) detectors/alarms. Interestingly, there seems to be confusion about the optimal placement, if any, of CO alarms inside the home.

Objectives

It was the goal of this study to demonstrate the behavior of CO in air and to help provide a data-based recommendation for CO alarm placement.

Methods

CO was calculated to be slightly lighter than air. An 8-foot-tall airtight Plexiglas chamber was constructed and CO monitors placed within at the top, middle, and bottom. CO test gas (15 L, 3000 parts per million) was infused at each of the three heights in different trials and CO levels measured over time.

Results

Contrary to a significant amount of public opinion, CO did not layer on the floor, float at the middle of the chamber, or rise to the top. In each case, the levels of CO equalized throughout the test chamber. It took longer to equalize when CO was infused at the top of the chamber than the bottom, but levels always became identical with time.

Conclusions

As would have been predicted by the Second Law of Thermodynamics, CO infused anywhere within the chamber diffused until it was of equal concentration throughout. Mixing would be even faster in the home environment, with drafts due to motion or temperature. It would be reasonable to place a residential CO alarm at any height within the room.     

Architecture and inherent robustness of a bacterial cell-cycle control system

A closed-loop control system drives progression of the coupled stalked and swarmer cell cycles of the bacterium Caulobacter crescentus in a near-mechanical step-like fashion. The cell-cycle control has a cyclical genetic circuit composed of four regulatory proteins with tight coupling to processive chromosome replication and cell division subsystems. We report a hybrid simulation of the coupled cell-cycle control system, including asymmetric cell division and responses to external starvation signals, that replicates mRNA and protein concentration patterns and is consistent with observed mutant phenotypes. An asynchronous sequential digital circuit model equivalent to the validated simulation model was created. Formal model-checking analysis of the digital circuit showed that the cell-cycle control is robust to intrinsic stochastic variations in reaction rates and nutrient supply, and that it reliably stops and restarts to accommodate nutrient starvation. Model checking also showed that mechanisms involving methylation-state changes in regulatory promoter regions during DNA replication increase the robustness of the cell-cycle control. The hybrid cell-cycle simulation implementation is inherently extensible and provides a promising approach for development of whole-cell behavioral models that can replicate the observed functionality of the cell and its responses to changing environmental conditions.     

Fabrication of tissue‐engineered cell sheets by automated cell culture equipment

Most cells for regenerative medicine are currently cultured manually. In order to promote the widespread use of regenerative medicine, it will be necessary to develop automated culture techniques so that cells can be produced in greater quantities at lower cost and with more stable quality. In the field of regenerative medicine technology, cell sheet therapy is an effective tissue engineering technique whereby cells can be grafted by attaching them to a target site. We have developed automated cell culture equipment to promote the use of this cell sheet regenerative treatment. This equipment features a fully closed culture vessel and circuit system that avoids contamination with bacteria and the like from the external environment, and it was designed to allow 10 cell sheets to be simultaneously cultured in parallel. We used this equipment to fabricate 50 sheets of human oral mucosal epithelial cells in five automated culture tests in this trial. By analyzing these sheets, we confirmed that 49 of the 50 sheets satisfied the quality standards of clinical research. To compare the characteristics of automatically fabricated cell sheets with those of manually fabricated cell sheets, we performed histological analyses using immunostaining and transmission electron microscopy. The results confirmed that cell sheets fabricated with the automated cell culture are differentiated in the same way as cultures fabricated manually.     

精神分裂症暴力行为的心理行为干预方法研究

目的探讨3种不同呼吸机湿化管道系统对建立人工气道机械通气患者湿化效果的影响。方法收集建立人工气道机械通气48h以上患者90例，随机分为A、B、C3组各30例。A组使用MR410型（吸气与呼气管路均无加热丝）湿化管道系统；B组使用MR730型（吸气管路带加热丝而呼气管路无加热丝）湿化管道系统；C组采用MR850型（密闭式一次性、双加热式自动加水、加湿）湿化管道系统。3组湿化液均使用灭菌注射用水。对3组气道分泌物黏稠度、管道痰痂形成及气道痉挛情况进行比较。结果3组患者在气道分泌物黏稠度、管道痰痂形成、气道痉挛等方面的比较，差异有统计学意义（P〈0．01）；C组无管道痰痂形成，亦无气道痉挛发生。结论机械通气患者呼吸道湿化效果与呼吸机管道湿化系统的管道是否有加热丝有关，加热湿化系统管道，有利于改善气道湿化效果。     

光学法与电阻抗法血小板计数差异及仪器报警信息分析

目的：以手工显微镜计数法为参考,比较光学法与电阻抗法计数血小板的差异,并对仪器报警信息进行分析。方法应用SysmexXE‐2100全自动血液分析仪,同时采用光学法、电阻抗法检测468例患者的血小板计数（PLT‐O、PLT‐I）,并与手工显微镜计数法检测的血小板计数（PLT‐M）进行比较,同时镜检观察红细胞与血小板的数量及形态,并记录仪器的红细胞和血小板的报警信息。结果非血液病组中,PLT‐M、PLT‐I、PLT‐O差异无统计学意义（P＝0．071）。血液病组中,PLT‐I与PLT‐M、PLT‐O差异均有统计学意义（P＜0．05）,PLT‐M与PLT‐O差异无统计学意义（P＞0．05）。血液病组仪器出现血小板报警信息者149例,出现红细胞报警信息者127例,与镜检结果较符合。结论当血小板计数低于正常参考范围内时,PLT‐I计数误差较大,需PLT‐M和PLT‐O方法复检或校正;当出现血小板或红细胞报警信息时,均需涂片复检。     

Habit learning is associated with major shifts in frequencies of oscillatory activity and synchronized spike firing in striatum

Rhythmic brain activity is thought to reflect, and to help organize, spike activity in populations of neurons during on-going behavior. We report that during learning, a major transition occurs in task-related oscillatory activity in the ventromedial striatum, a striatal region related to motivation-dependent learning. Early on as rats learned a T-maze task, bursts of 70- to 90-Hz high-γ activity were prominent during T-maze runs, but these gradually receded as bursts of 15- to 28-Hz β-band activity became pronounced. Populations of simultaneously recorded neurons synchronized their spike firing similarly during both the high-γ-band and β-band bursts. Thus, the structure of spike firing was reorganized during learning in relation to different rhythms. Spiking was concentrated around the troughs of the β-oscillations for fast-spiking interneurons and around the peaks for projection neurons, indicating alternating periods of firing at different frequencies as learning progressed. Spike-field synchrony was primarily local during high-γ-bursts but was widespread during β-bursts. The learning-related shift in the probability of high-γ and β-bursting thus could reflect a transition from a mainly focal rhythmic inhibition during early phases of learning to a more distributed mode of rhythmic inhibition as learning continues and behavior becomes habitual. These dynamics could underlie changing functions of the ventromedial striatum during habit formation. More generally, our findings suggest that coordinated changes in the spatiotemporal relationships of local field potential oscillations and spike activity could be hallmarks of the learning process.     

Weight loss effects of circuit training interventions: A systematic review and meta‐analysis

This meta‐analysis aimed to assess the weight loss effects of circuit training interventions in adults. A computerized search was conducted using the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE online databases. The analysis was restricted to randomized controlled trials that evaluated the effects of circuit training interventions on body weight and body mass index in adults aged 18 years or older. Meta‐analyses were conducted using the random‐effect model to estimate the weighted mean difference (WMD) with 95% confidence interval (CI). Nine randomized controlled trials (837 participants) were included. Significant intervention effects were identified for body weight (WMD = ?3.81 kg, 95% CI ?5.60 to ?2.02) and body mass index (WMD = ?1.77 kg/m², 95% CI ?2.49 to ?1.04). Subgroup analysis by body mass index status showed that the intervention effect was significant only in participants with obesity or overweight (obesity: WMD = ?5.15 kg, 95% CI ?8.81 to ?1.50 and overweight: WMD = ?3.89 kg, 95% CI ?7.00 to ?0.77, respectively) but not in those with normal weight. Current evidence suggests that circuit training effectively reduces body weight and body mass index in adults with overweight and obesity.     

Alarms for Continuous Glucose Monitors: Alarm Characterization for Continuous Glucose Monitors Used as Adjuncts to Self-Monitoring of Blood Glucose

Background

Continuous glucose monitoring (CGM) devices available in the United States are approved for use as adjuncts to self-monitoring of blood glucose (SMBG). Alarm evaluation in the Clinical and Laboratory Standards Institute (CLSI) guideline for CGM does not specifically address devices that employ both CGM and SMBG. In this report, an alarm evaluation method is proposed for these devices.

Method

The proposed method builds on the CLSI method using data from an in-clinic study of subjects with type 1 diabetes. CGM was used to detect glycemic events, and SMBG was used to determine treatment. To optimize detection of a single glucose level, such as 70 mg/dl, a range of alarm threshold settings was evaluated. The alarm characterization provides a choice of alarm settings that trade off detection and false alarms. Detection of a range of high glucose levels was similarly evaluated.

Results

Using low glucose alarms, detection of 70 mg/dl within 30 minutes increased from 64 to 97% as alarm settings increased from 70 to100 mg/dl, and alarms that did not require treatment (SMBG >85 mg/dl) increased from 18 to 52%. Using high glucose alarms, detection of 180 mg/dl within 30 minutes increased from 87 to 96% as alarm settings decreased from 180 to 165 mg/dl, and alarms that did not require treatment (SMBG <180 mg/dl) increased from 24 to 42%.

Conclusion

The proposed alarm evaluation method provides information for choosing appropriate alarm thresholds and reflects the clinical utility of CGM alarms.