Widespread spatial integration in primary somatosensory cortex

Tactile discrimination depends on integration of information from the discrete receptive fields (RFs) of peripheral sensory afferents. Because this information is processed over a hierarchy of subcortical nuclei and cortical areas, the integration likely occurs at multiple levels. The current study presents results indicating that neurons across most of the extent of the hand representation in monkey primary somatosensory cortex (area 3b) interact, even when these neurons have separate RFs. We obtained simultaneous recordings by using a 100-electrode array implanted in the hand representation of primary somatosensory cortex of two anesthetized owl monkeys. During a series of 0.5-s skin indentations with single or dual probes, the distance between electrodes from which neurons with synchronized spike times were recorded exceeded 2 mm. The results provide evidence that stimuli on different parts of the hand influence the degree of synchronous firing among a large population of neurons. Because spike synchrony potentiates the activation of commonly targeted neurons, synchronous neural activity in primary somatosensory cortex can contribute to discrimination of complex tactile stimuli.     

Differential classical conditioning selectively heightens response gain of neural population activity in human visual cortex

Neutral cues, after being reliably paired with noxious events, prompt defensive engagement and amplified sensory responses. To examine the neurophysiology underlying these adaptive changes, we quantified the contrast‐response function of visual cortical population activity during differential aversive conditioning. Steady‐state visual evoked potentials (ssVEPs) were recorded while participants discriminated the orientation of rapidly flickering grating stimuli. During each trial, luminance contrast of the gratings was slowly increased and then decreased. Right‐tilted gratings (CS+) were paired with loud white noise but left‐tilted gratings (CS?) were not. The contrast‐following waveform envelope of ssVEPs showed selective amplification of the CS+ only during the high‐contrast stage of the viewing epoch. Findings support the notion that motivational relevance, learned in a time frame of minutes, affects vision through a response gain mechanism.     

Novel adjunctive treatments of myocardial infarction

Myocardial infarction is a major cause of death and disability worldwide and myocardial infarct size is a major determinant of prognosis. Early and successful restoration of myocardial reperfusion following an ischemic event is the most effective strategy to reduce final infarct size and improve clinical outcome,but reperfusion may induce further myocardial damage itself. Development of adjunctive therapies to limit myocardial reperfusion injury beyond opening of the coronary artery gains increasing attention. A vast number of experimental studies have shown cardioprotective effects of ischemic and pharmacological conditioning,but despite decades of research,the translation into clinical effects has been challenging. Recently published clinical studies,however,prompt optimism as novel techniques allow for improved clinical applicability. Cyclosporine A,the GLP-1 analogue exenatide and rapid cooling by endovascular infusion of cold saline all reduce infarct size and may confer clinical benefit for patients admitted with acute myocardial infarcts. Equally promising,three follow-up studies of the effect of remote ischemic conditioning(RIC) show clinical prognostic benefit in patients undergoing coronary surgery and percutaneous coronary intervention. The discovery that RIC canbe performed noninvasively using a blood pressure cuff on the upper arm to induce brief episodes of limb ischemia and reperfusion has facilitated the translation of RIC into the clinical arena. This review focus on novel advances in adjunctive therapies in relation to acute and elective coronary procedures.     

两种不同治疗方案对70例多囊卵巢综合征不孕患者的治疗效果研究

目的 探讨多囊卵巢综合征不孕患者体外受精-胚胎移植(IVF/ICSI)技术辅助生育时不同的降调节方案对于助孕治疗结局的影响。方法 纳入2016年10月～2018年2月在我院生殖中心助孕治疗的70例多囊卵巢综合征(PCOS)不孕女性作为研究对象,根据控制性超促排卵(COS)所应用的降调节方案的不同将患者随机分为两组：长效长方案组(A组)35例,经典长方案组(B组)35例。A组降调节是于早卵泡期注射长效GnRHa,B组降调节是于黄体中期使用短效GnRHa。对比研究两组方案的刺激天数(Gn天数)、以及促性腺激素使用的总剂量(Gn量)、HCG扳机日子宫内膜厚度、激素水平、取卵后的获成熟卵率(MII卵率)、优质胚胎率、移植后的种植率、临床妊娠率及全胚胎冷冻率。结果 (1)两组比较A组的Gn量和优胚率高于B组,HCG扳机日雌二醇、孕酮水平低于B组,差异均有统计学意义(P＜0.05);(2)两组的Gn天数、HCG扳机日的子宫内膜厚度、获成熟卵率、种植率以及临床妊娠率相比较,差异无统计学意义(P＞0.05)。结论 长效长方案较经典长方案可以达到充分降调节的目的,抑制了黄体生成素(LH)峰在超促排卵前及过程中的出现,可以提高多囊卵巢综合征患者的优胚率、降低HCG扳机日孕酮水平,改善其妊娠结局,可以成为多囊卵巢综合征不孕患者控制性超促排卵的一个理想选择。     

CXCR4 blockade and Sphingosine‐1‐phosphate activation facilitate engraftment of haematopoietic stem and progenitor cells in a non‐myeloablative transplant model

Both immunosuppressive and cytoreductive effects of γ‐irradiation contribute to engraftment of allogeneic haematopoietic stem and progenitor cells. We hypothesized that a release of host stem and progenitor cells from the niche prior to conditioning would permit engraftment after less intensive conditioning. Administration of AMD3100 and SEW2871 on days ?4 to ?2 followed by irradiation on day ?1 in a non‐myeloablative zebrafish transplant model resulted in a reduced radiation minimum dose of 10 Gy from 15 Gy being sufficient for engraftment. Targeting the SDF‐1 (CXCL12)/CXCR4‐ and S1P/S1P₁‐axis increased the efficacy of allografting in an experimental transplant model.