心率变异性生物反馈调节自主神经系统的机制及应用

背景:心率变异性生物反馈是采用共振频率下的深慢呼吸方式在心血管系统中引起有节奏的高幅度振荡,从而刺激和锻炼自主神经反射及压力反射的一种呼吸训练方式。然而,目前的研究尚未系统综述心率变异性生物反馈是如何调节自主神经功能并产生作用的。研究者们对心率变异性生物反馈的机制缺乏全面认识,且对其应用进展及方案尚不完全清楚。目的:对国内外现有的心率变异性生物反馈对不同人群症状影响的试验研究进行梳理,介绍心率变异性生物反馈调节自主神经系统的机制及应用进展。方法:以“心率变异性生物反馈,共振呼吸,自主神经,心率变异性,生物反馈,呼吸训练”“Heart rate variability biofeedback,Resonance breathing,Heart rate variability,Autonomic nerve,Breathing training,Chronic diseases,Mental illness,biofeedback”等为检索词在中国知网、万方、PubMed及Web of Science等文献数据库进行检索,根据纳入和排除标准共获得相关文献75篇。结果与结论:①机体的振荡系统与共振系统是心率变异性生物反馈产生作用的前提,振荡反映了外部刺激和自身调节的反射系统的运作,共振则是两个系统的同步振荡引起更高的振幅运作。②交感神经和副交感神经平衡是维持稳定的内环境的前提,自主神经系统紊乱会伴随心率变异性降低并与相关疾病的进展密切相关。心率变异性生物反馈是基于心血管系统的共振特性,以共振频率下的深慢呼吸方式在心血管系统中引起有节奏的高幅度振荡,改善交感和副交感系统反射的调节功能,增强两个系统之间的平衡调节。③心血管系统共振的两个主要机制是压力反射闭环通路和呼吸性窦性心律失常,两个机制以及压力反射特有的延迟共同作用导致在共振频率节奏的呼吸时,心率与呼吸呈现0°相位角的振荡,血压与呼吸呈现180°相位角振荡,是一种易操作、效果好的周期性刺激人体心血管振荡系统的训练方法。④目前心率变异性生物反馈大多应用于心理疾病、慢病以及体育领域,但其存在干预机制及功效不清,干预内容、干预频率及干预时间存在差异,未有研究针对不同类型人群对应的干预方式做相关综述研究。⑤心率变异性生物反馈作为一种非药物、非侵入性的干预手段,可以显著提高心率变异性,调节交感神经与副交感神经平衡,改善自主神经系统的稳定性和弹性。未来建议探索其诱发心血管共振通路的机制与应用情况,添加长期随访,以评估其在不同领域中的长期应用价值,为一些复杂疾病的综合治疗提供新的方向和策略。

热带西太平洋海区生物-光学变异性

在海上测量期间，观测到几次浮游植物大量繁殖过程，每次分别持续8—18d，叶绿素含量分别升高约3—10倍。由于浮游植物大量繁殖，光束衰减系数随叶绿素a含量升高而增大。谱分析的结果表明，光束衰减系数与叶绿素a含量的时间序列有较好的相干性，其相干系数在0．6—1．0之间。在此基础上，讨论了生物-光学变异性与海洋物理过程的关系。结果表明，混合层深度及水温等物理参数的变化是导致生物-光学特性在数十天时域尺度上变化的重要因素。

心率变异性生物反馈训练对基层指挥员亚健康的影响

目的探讨心率变异性生物反馈(heart ratevariability biofeedback,HRVB)训练对基层指挥员亚健康及心率变异性(heartratevariability,HRV)的影响,为提高基层指挥员心理健康水平及心理生理能力提供依据。方法采用两因素混合实验设计(组别×训练次数),选取47名陆军基层指挥员,完全随机分为对照组22名(不接受HRVB训练)和实验组25名(接受HRVB训练)。采用亚健康评定量表和HRV评估实验前后指挥员亚健康心理和生理状况。结果HRVB训练后实验组亚健康状况较训练前明显改善(P<0.05);对照组HRV正常窦性心搏间期的标准差(standard deviation of all normal to normal intervals,SDNN)、极低频(verylow frequency,VLF)、总功率谱密度(total power,TP)呈下降趋势,且差异均有统计学意义(P均<0.05),而实验组保持相对稳定的状态,差异无统计学意义(P>0.05);实验组在训练3周后,HRV SDNN、全程相邻间期之差的均方根(root mean square of the successive normal to normal inter-valsdifference,rMSSD)、VLF、TP显著高于对照组(P均<0.05)。结论HRVB训练能有效改善基层指挥员亚健康水平及心理生理能力。

生物反馈治疗技术在临床应用中的研究进展

近年来,随着生物反馈技术的迅猛发展,其在临床中的应用越来越广泛,在各种疾病的治疗中也取得了良好的效果。本文就生物反馈的发展、定义、治疗原理、生物反馈的各种治疗方式进行相关介绍,分别讨论了生物反馈治疗技术在神经精神系统、心血管系统、呼吸系统、消化系统等方面的应用。此外还评估了生物反馈不同的治疗方式对不同系统干预后的相关结果进行评价。

Genetic variation of natural and cultured stocks of Paralichthys olivaceus by allozyme and RAPD

Population genetics of the left-eyed flounder, Paralichthys olivaceus, including natural and cultured stocks distributed in the coastal waters near Qingdao of eastern maritime China, was analyzed in allozyme and RAPD. The results showed that among total 29 gene loci of 15 isozymes, 9 and 7 were po- lymorphic in natural and cultured stocks, respectively. The status of genetic diversity in P. olivaceus is low in terms of polymorphic loci in chi-square test and genetic departure index of Hardy-Weinberg equi- librium. More alleles in IDHP, CAT, GDH and Ldh-C allozymes were found in the fish, which could be used as markers in assortive breeding and distinguishing stock, population or species evolution. Total 88 and 86 RAPD bands ranging from 200 to 2 500 bp were recognized individually in average of 7.8–8.0 bands per primer. The genetic diversity in cultured stock is lower than that in natural ones showing an ob- viously decreasing genetic divergence. Therefore, effective countermeasures must be taken to protect ge- netic resources of marine cultured fishes. The 2 markers have their own pros and cons. Combining the 2 markers to investigate the genetic variation of populations is suggested. The results provide basic data of this flounder and they are useful for studying genetic improvement and genetic resources of the fish.

Spatial heterogeneity in a deep artificial lake plankton community revealed by PCR-DGGE fingerprinting

To explore the spatial heterogeneity of plankton communities in a deep artificial lake （Songhua Lake, China）, samples were collected at seven sites. Samples were investigated by denaturing gradient gel electrophoresis （DGGE） analysis of the PCR-amplified 16S and 18S rRNA genes and specific bands were sequenced. Cluster analysis of the DGGE profiles revealed that all of the samples grouped into two distinct clusters, in accordance with sampling site; while in each cluster, the divergence of sub-clusters correlated with sampling depth. Sequence analysis of selected dominant DGGE bands revealed that most sequenced phylotypes （84%） exhibited 〉97% similarity to the closest sequences in GenBank, and were affiliated with ten common freshwater plankton phyla （Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Bacillariophyta, Pyrrophyta, Cryptophyta, Ciliophora, Stramenopiles, and Rotifera）. Several of these groups are also found worldwide, indicating the cosmopolitan distribution of the phylotypes. The relationships between DGGE patterns and environmental factors were analyzed by redundancy analysis （RDA）. The results suggested that, total nitrogen, nitrate, nitrite, temperature were strongly correlated with the variation ammonia, and CODMn concentrations, and water in plankton composition.

Effect of hydrological variability on diatom distribution in Poyang Lake, China

Poyang Lake is the largest freshwater lake in China, and it has a seasonal flooding cycle that significantly changes the water level every year. The aim of this paper was to explain how these hydrological changes influence diatom populations in Poyang Lake. The yearly hydrological cycle can be divided into 4 phases: low water-level phase, increasing water-level phase, high water-level phase and decreasing waterlevel phase. Variations in the abundance of planktonic diatoms were studied using quarterly monitoring data collected from January 2009 to October 2013. Generally, diatoms were dominant in Poyang Lake and accounted for more than 50% of the total phytoplankton biomass except in July 2009(26%) and January 2012(35%). Aulacoseira granulata and Surirella robusta were the predominant species in all four phases, and they accounted for 25.02% to 56.89% and 5.07% to 14.78% of the total phytoplankton biomass, respectively. A redundancy analysis(RDA) showed that changes in physico-chemical parameter were related to the water level, and changes in diatom biomass were related to nitrite levels and p H. These results indicate that changes in environmental parameters related to both seasonal variations and water-level fluctuations caused variations in diatom biomass and community composition in Poyang Lake. Furthermore, extreme hydrological events can have different influences on the diatom community composition in the main channel and lentic regions. This research provides data on the diatom variations in Poyang Lake and will be useful for establishing biological indicators of environmental change and protecting Poyang Lake in the future.

NEW ANTIMICROBIAL SENSITIVITY TESTS OF BIOFILM OF STREPTOCOCCUS MUTANS IN ARTIFICIAL MOUTH MODEL

Objective To develop a new antimicrobial sensitivity test model for oral products in vitro.Methods A biofilm artificial mouth model for antimicrobial sensitivity tests was established by modifying the LKB chromatography chamber. Using sodium fluoride and Tea polyphenol as antimicrobial agent and Streptococcus mu-tans as target, sensitivity tests were studied. Results The modeling biofilm assay resulted in a MIC of 1. 28mg/ ml for fluoride against S. mutans, which was 32 times the MIC for broth maco-dilution method. The differential resistance of bacteria bioflim to antimicrobial agent relative to planktonic cells was also demonstrated. Conclusion The biofilm artificial mouth model may be useful in oral products test.

Differences in functional traits among distinct populations of the plant invader Bunias orientalis

Plants that expand their range and become invasive in other areas may shift several functional traits in response to specific environments.However,local conditions at the place of origin may have shaped the functional traits,which may to some extent remain visible in plants growing in new habitats.The present study aimed to explore the trait variation in different plant populations of native,invasive and naturalized status of Bunias orientalis grown in common conditions in relation to the climatic conditions at their place of origin.Seeds of B.orientalis were collected from 12 populations(4 per status)in 8 countries and grown under standardized conditions in a common field garden.The variation in several functional traits related to phenology,growth and reproduction was compared among status and among populations.Phenology did not differ according to status.However,several plants of the native populations,originating from areas with low annual temperatures,did not start flowering.Plants of the invasive populations produced more leaves than natives,potentially indicating their vigor in building up vegetative biomass.Number and mass of silicles and other growth traits did not differ among status groups but varied among populations.Some of the variation in functional traits may be explained by long-term adaptations to local conditions at the areas of origin and genetic diversity,while other environmental factors differing in the novel environment may contribute to a high trait variation.