Empathy for pain involves the affective but not sensory components of pain

Our ability to have an experience of another's pain is characteristic of empathy. Using functional imaging, we assessed brain activity while volunteers experienced a painful stimulus and compared it to that elicited when they observed a signal indicating that their loved one--present in the same room--was receiving a similar pain stimulus. Bilateral anterior insula (AI), rostral anterior cingulate cortex (ACC), brainstem, and cerebellum were activated when subjects received pain and also by a signal that a loved one experienced pain. AI and ACC activation correlated with individual empathy scores. Activity in the posterior insula/secondary somatosensory cortex, the sensorimotor cortex (SI/MI), and the caudal ACC was specific to receiving pain. Thus, a neural response in AI and rostral ACC, activated in common for "self" and "other" conditions, suggests that the neural substrate for empathic experience does not involve the entire "pain matrix." We conclude that only that part of the pain network associated with its affective qualities, but not its sensory qualities, mediates empathy.     

Does rejection hurt? An FMRI study of social exclusion

A neuroimaging study examined the neural correlates of social exclusion and tested the hypothesis that the brain bases of social pain are similar to those of physical pain. Participants were scanned while playing a virtual ball-tossing game in which they were ultimately excluded. Paralleling results from physical pain studies, the anterior cingulate cortex (ACC) was more active during exclusion than during inclusion and correlated positively with self-reported distress. Right ventral prefrontal cortex (RVPFC) was active during exclusion and correlated negatively with self-reported distress. ACC changes mediated the RVPFC-distress correlation, suggesting that RVPFC regulates the distress of social exclusion by disrupting ACC activity.     

Enhancement of consolidated long-term memory by overexpression of protein kinase Mzeta in the neocortex

Memories are more easily disrupted than improved. Many agents can impair memories during encoding and consolidation. In contrast, the armamentarium of potential memory enhancers is so far rather modest. Moreover, the effect of the latter appears to be limited to enhancing new memories during encoding and the initial period of cellular consolidation, which can last from a few minutes to hours after learning. Here, we report that overexpression in the rat neocortex of the protein kinase C isozyme protein kinase Mζ (PKMζ) enhances long-term memory, whereas a dominant negative PKMζ disrupts memory, even long after memory has been formed.     

Anterior cingulate conflict monitoring and adjustments in control

Conflict monitoring by the anterior cingulate cortex (ACC) has been posited to signal a need for greater cognitive control, producing neural and behavioral adjustments. However, the very occurrence of behavioral adjustments after conflict has been questioned, along with suggestions that there is no direct evidence of ACC conflict-related activity predicting subsequent neural or behavioral adjustments in control. Using the Stroop color-naming task and controlling for repetition effects, we demonstrate that ACC conflict-related activity predicts both greater prefrontal cortex activity and adjustments in behavior, supporting a role of ACC conflict monitoring in the engagement of cognitive control.     

Neural mechanisms of foraging

Behavioral economic studies involving limited numbers of choices have provided key insights into neural decision-making mechanisms. By contrast, animals' foraging choices arise in the context of sequences of encounters with prey or food. On each encounter, the animal chooses whether to engage or, if the environment is sufficiently rich, to search elsewhere. The cost of foraging is also critical. We demonstrate that humans can alternate between two modes of choice, comparative decision-making and foraging, depending on distinct neural mechanisms in ventromedial prefrontal cortex (vmPFC) and anterior cingulate cortex (ACC) using distinct reference frames; in ACC, choice variables are represented in invariant reference to foraging or searching for alternatives. Whereas vmPFC encodes values of specific well-defined options, ACC encodes the average value of the foraging environment and cost of foraging.     

Inhibition of pyruvate kinase M2 by reactive oxygen species contributes to cellular antioxidant responses

Control of intracellular reactive oxygen species (ROS) concentrations is critical for cancer cell survival. We show that, in human lung cancer cells, acute increases in intracellular concentrations of ROS caused inhibition of the glycolytic enzyme pyruvate kinase M2 (PKM2) through oxidation of Cys(358). This inhibition of PKM2 is required to divert glucose flux into the pentose phosphate pathway and thereby generate sufficient reducing potential for detoxification of ROS. Lung cancer cells in which endogenous PKM2 was replaced with the Cys(358) to Ser(358) oxidation-resistant mutant exhibited increased sensitivity to oxidative stress and impaired tumor formation in a xenograft model. Besides promoting metabolic changes required for proliferation, the regulatory properties of PKM2 may confer an additional advantage to cancer cells by allowing them to withstand oxidative stress.     

Learned predictions of error likelihood in the anterior cingulate cortex

The anterior cingulate cortex (ACC) and the related medial wall play a critical role in recruiting cognitive control. Although ACC exhibits selective error and conflict responses, it has been unclear how these develop and become context-specific. With use of a modified stop-signal task, we show from integrated computational neural modeling and neuroimaging studies that ACC learns to predict error likelihood in a given context, even for trials in which there is no error or response conflict. These results support a more general error-likelihood theory of ACC function based on reinforcement learning, of which conflict and error detection are special cases.     

Mnemonic function of the dorsolateral prefrontal cortex in conflict-induced behavioral adjustment

Our cognitive abilities in performing tasks are influenced by experienced competition/conflict between behavioral choices. To determine the role of the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (DLPFC) in the conflict detection-resolution process, we conducted complementary lesion and single-cell recording studies in monkeys that were resolving a conflict between two rules. We observed conflict-induced behavioral adjustment that persisted after lesions within the ACC but disappeared after lesions within the DLPFC. In the DLPFC, activity was modulated in some cells by the current conflict level and in other cells by the conflict experienced in the previous trial. These results show that the DLPFC, but not the ACC, is essential for the conflict-induced behavioral adjustment and suggest that encoding and maintenance of information about experienced conflict is mediated by the DLPFC.     

Perceptual learning incepted by decoded fMRI neurofeedback without stimulus presentation

It is controversial whether the adult primate early visual cortex is sufficiently plastic to cause visual perceptual learning (VPL). The controversy occurs partially because most VPL studies have examined correlations between behavioral and neural activity changes rather than cause-and-effect relationships. With an online-feedback method that uses decoded functional magnetic resonance imaging (fMRI) signals, we induced activity patterns only in early visual cortex corresponding to an orientation without stimulus presentation or participants' awareness of what was to be learned. The induced activation caused VPL specific to the orientation. These results suggest that early visual areas are so plastic that mere inductions of activity patterns are sufficient to cause VPL. This technique can induce plasticity in a highly selective manner, potentially leading to powerful training and rehabilitative protocols.     

Alcohol consumption impairs detection of performance errors in mediofrontal cortex

The anterior cingulate cortex (ACC) is a critical component of the human mediofrontal neural circuit that monitors ongoing processing in the cognitive system for signs of erroneous outcomes. Here, we show that the consumption of alcohol in moderate doses induces a significant deterioration of the ability to detect the activation of erroneous responses as reflected in the amplitude of brain electrical activity associated with the ACC. This impairment was accompanied by failures to instigate performance adjustments after these errors. These findings offer insights into how the effects of alcohol on mediofrontal brain function may result in compromised performance.     

转C_4基因水稻的生理表现

以C3水稻原种(WT)和C4玉米为材料,研究了转PEPC+PPDK+ME基因水稻(PKM)的C4光合酶活性、不同光温条件下光合参数和水分利用效率、活性氧代谢等指标。结果表明,PKM水稻饱和光合速率介于WT和C4玉米之间,稍偏向玉米,而水分利用效率与WT接近。由于玉米C4基因的导入,PKM水稻高表达了相关的C4光合酶。在高光和高温条件下,PKM水稻光合速率比原种提高55%以上。另外,虽然PKM水稻光合速率增加,但蒸腾速率亦升高,因此PKM水稻的水分利用效率略有增加,偏向原种。在光氧化条件下,PKM水稻耐光氧化能力进一步增强。     

气调对猕猴桃果实采后乙烯生成的效应及其机制

气调贮藏条件下猕猴桃果实成熟延缓,组织内乙烯含量及乙烯生成速率明显低于对照,气调 处理抑制乙烯生成的效应主要通过抑制ＡＣＣ合成实现,也抑制ＡＣＣ氧化酶活性,降低ＡＣＯ／ＡＣＣ＋ ＭＡＣＣ）比值, ＡＣＣ含量是猕猴桃果实采后乙烯生成的限制因子。气调条件下果实组织内乙烯含量、 ＡＣＣ含量及ＡＣＣ氧化酶活性变化出现交替升降现象。     

Lateralized cognitive processes and lateralized task control in the human brain

The principles underlying human hemispheric specialization are poorly understood. We used functional magnetic resonance imaging of letter and visuospatial decision tasks with identical word stimuli to address two unresolved problems. First, hemispheric specialization depended on the nature of the task rather than on the nature of the stimulus. Second, analysis of frontal candidate regions for cognitive control showed increased coupling between left anterior cingulate cortex (ACC) and left inferior frontal gyrus during letter decisions, whereas right ACC showed enhanced coupling with right parietal areas during visuospatial decisions. Cognitive control is thus localized in the same hemisphere as task execution.     

辣木幼苗对淹水胁迫的生理响应及耐涝性综合评价

【目的】探究辣木幼苗对淹水胁迫的生理响应规律及其耐涝性,为辣木耐涝品种选育及抗涝栽培机理研究提供参考。【方法】供试材料为多油辣木（Moringa oleifera Lam.）、PKM1（多油辣木中选育出的品种）、狭瓣辣木[Moringa stenopetala（Baker f.）Cufod],设置正常水分（CK）和淹水处理,胁迫后测定辣木幼苗叶片的可溶性糖（SS）、可溶性蛋白（SP）、脯氨酸（Pro）、Chl a、Chl b、类胡萝卜素（Car）、Chl a/b、Chl a+b、总叶绿素（Chl T）、暗适应初始荧光（F_o）、暗适应最大荧光（F_m）、光系统II（PSII）最大光化学效率（F_v/F_m）、光适应下PSII实际光化学量子产量（ΦPSII）、光合电子传递速率（ETR）、非光化学猝灭系数（NPQ）、光化学淬灭系数（qP）,并综合评价多油辣木、PKM1和狭瓣辣木的耐涝性。【结果】PKM1和狭瓣辣木的SS、SP和Pro含量在淹水后较CK分别显著上升38.64%、86.81%、351.07%和69.66%、139.22%、567.69%（P<0.05,下同）;淹水后,多油辣木的SS含量较CK显著上升29.12%,但SP含量显著下降55.35%。淹水后,多油辣木的Chl b含量较CK显著下降36.59%,狭瓣辣木的Car含量较CK显著上升57.14%;多油辣木、PKM1和狭瓣辣木的Chl a/b含量在淹水后较CK分别显著上升36.41%、38.92%和26.34%。淹水后,多油辣木、PKM1和狭瓣辣木的F_o较CK显著上升,F_v/F_m、ΦPSII、ETR、qP较CK分别显著下降,NPQ与CK差异不显著（P>0.05）;PKM1和狭瓣辣木的F_m在淹水后较CK分别显著下降37.79%和34.90%。快速光响应曲线结果显示,淹水后多油辣木、PKM1和狭瓣辣木的ETR_max分别下降;淹水处理ETR_max的排序依次为狭瓣辣木 > PKM1 > 多油辣木。利用主成分分析、隶属函数法和聚类分析等多元分析方法对16个单指标进行综合分析可知,其耐涝性依次为狭瓣辣木 > PKM1 > 多油辣木。【结论】淹水导致辣木幼苗的渗透调节物质上调,且严重影响植株的光合和叶绿素荧光特性。因此,在辣木幼苗期应加强涝渍防控,出现积水应及时排水。在涝害发生频繁的区域应选择耐涝性品种。     

Placebo-induced changes in FMRI in the anticipation and experience of pain

The experience of pain arises from both physiological and psychological factors, including one's beliefs and expectations. Thus, placebo treatments that have no intrinsic pharmacological effects may produce analgesia by altering expectations. However, controversy exists regarding whether placebos alter sensory pain transmission, pain affect, or simply produce compliance with the suggestions of investigators. In two functional magnetic resonance imaging (fMRI) experiments, we found that placebo analgesia was related to decreased brain activity in pain-sensitive brain regions, including the thalamus, insula, and anterior cingulate cortex, and was associated with increased activity during anticipation of pain in the prefrontal cortex, providing evidence that placebos alter the experience of pain.     

Morphological Changes in Hippocampus and Prefrontal Cortex of Confined Sows with Prolonged Pupillary Light Reflex

Human depression patients often show abnormal pupillary reflex with morphological changes in hippo campus and prefrontal cortex.This study aimed to find the relationship between the prolonged pupillary light reflex(PLR) which had been shown by confined sows with chronic stress or depression and morphological changes in brain,in order to provide theoretical basis for that the confined environment should lead to sows' depression.A total of 637 sows of Durac,Landrace and Large White breeds with various parities were observed,and the pupil light reflex(PLR) was measured and the actual pupillary light reflex time(PLRT) were recorded.All the PLRTs were grouped based on the results of confidence interval:t10%as group A,5%t10%as group B,1%t5%as group C and t1%as group D.Three individuals were randomly selected from each group(12 sows in total) and the white tissues of hippocampus and the prefrontal cortex were prepared for HS staining slices(three slices/per tissue) for observation on tissue structure and pathological changes with high magnification(400X) of electronic microscope.The results showed that in group A(t10%) pathological change was found in hippocampus,however,as PLRT increased from group B to group D,pathological changes in hippocampus tissues tended to be deteriorated with the increase of inflammatory cells and nuclear pyknosis phenomena.The same as those shown in hippocampus as the increasing of PLRT from groups A to D,more inflammatory cells appeared in prefrontal cortex for groups B and D.The results suggested that the tissue lesions of hippocampus and prefrontal cortex of the confined sows with prolonged PLRT might be the results of chronic stress or depression.     

李果实成熟软化过程中生理特性及乙烯合成变化的研究

以乙烯合成途径为线索,研究李(Prunus domestica L.)果实成熟软化过程中硬度、可溶性固形物、可滴定酸、乙烯释放量、氨基环丙烷羧酸(ACC)和丙二酰氨基环丙烷羧酸(MACC)含量以及ACC合成酶(ACS)和ACC氧化酶(ACO)活性等指标的变化,探讨乙烯在李果实成熟软化中的作用。结果表明:李果实成熟软化过程中,硬度和可滴定酸的含量逐渐降低,可溶性固形物含量增加。李果实成熟期的软化启动阶段,乙烯释放量、ACC含量、ACS和ACO活性增强缓慢,此时乙烯释放量也比较低,ACS和ACO的活性都受到一定程度的抑制,在成熟过程中三者高峰值同时出现在软化后期。证明李果实成熟期的软化启动阶段,乙烯并非是软化启动因子,可能还存在其他的启动相关因子。     

棕仁粕基础营养分析及其在尼罗罗非鱼养殖中的应用研究

本文对比研究了棕仁粕、豆柏、花生粕的基础营养及体外胃蛋白酶消化性,通过在实验饲料中添加2％、6％、10％的棕仁粕制备了四份等氮等能的饲料,初步评价了添加棕仁粕对罗非鱼生长、体组分以及血清学参数的影响.结果表明:棕仁柏作为蛋白水平相对略低,纤维含量较高的植物蛋白替代源,其体外胃蛋白酶消化率与豆粕和花生粕无明显差异,可以作为膳食饲料组分适量的添加到水产动物饲料中,而不会影响罗非鱼的正常生长;在罗非鱼养殖实验中,添加2％棕仁粕的饲料组,罗非鱼的增重率,饲料系数,蛋白利用率、鱼体的蛋白组分以及血清学参数与对照组相比无显著差异(P＞0.05),添加至6％～10％后,罗飞鱼的生长表现开始下降,饲料系数开始上升,鱼体蛋白组分下降(P＜0.05).作为棕仁粕在水产养殖领域的初步探索性应用研究,研究认为棕仁粕是可以用于水产饲料的成分使用的,添加比例不宜超过6％.     

普通小麦TaZIP29-7B基因的克隆及表达研究

金属离子在小麦生长过程中起重要作用,但土壤中金属离子含量过高,会对小麦生长造成损害。锌铁转运蛋白ZIP家族(ZRT,IRT-like protein,ZIP)广泛存在于植物中,参与多种金属离子的转运,也能提高植物的耐盐性。利用同源克隆技术获得 AtZTP29在小麦中的同源基因TaZIP29-7B,并获得其启动子序列,利用生物信息学技术对所获得的基因以及启动子序列进行初步分析,预测启动子顺式作用元件,通过实时荧光定量PCR(Quantitative real-time PCR,qRT-PCR)技术分析小麦 TaZIP29-7B基因在根和叶中在不同金属离子溶液处理下的表达情况,以研究该基因在小麦体内中对重金属转运的作用。结果表明:序列分析显示 TaZIP29-7B基因(登录号MK203894)编码277个氨基酸,TaZIP29-7B蛋白为疏水性蛋白,定位在细胞膜上,存在信号肽,属于分泌蛋白,第89～263位置间的结构功能域ZIP,属于典型的ZIP超级家族结构域,具有8个跨膜区;进化分析显示TaZIP29-7B与单子叶植物山羊草(Aegilops tauschii)ZIP29蛋白同源性最高;启动子中存在多种响应胁迫的顺式作用元件;qRT-PCR结果显示,小麦 TaZIP29-7B基因在外界重金属盐的变化下表达量有所变化。说明研究结果为进一步改良小麦抗盐性提供了参考。     

番茄后熟期细胞超微结构与乙烯合成酶(EFE)活性关系的研究

对番茄采后各后熟生理时期的 ACC,乙烯水平及 EFE 酶活性变化以及与之相应的细胞超微结构进行了观察。乙烯产量从绿熟期到转红期没有明显变化,且水平相对较低。同时这几个时期的 ACC 水平也较一致。进入粉红期乙烯产量迅速上升并达到高峰,这时 ACC 水平降至最低点。高峰过后的全红期,过熟期乙烯水平迅速下降,而这时 ACC 水平逐渐上升至最高水平。EFE 酶活性在乙烯高峰前逐渐上升到最大值,高峰过后活性骤然降低直至失去活性。通过电镜观察,采后番茄果实细胞结构的最大变化在于乙烯高峰过后细胞壁的解体和质壁分离。在整个后热过程中,细胞膜结构、各细胞器依然完好,由于 ACC 的大量积累和乙烯水平下降与 EFE 活性有关,从而推断 EFE 酶的活性及作用不仅与膜结构有关而且同与膜有密切联系的细胞壁有关。