乙型肝炎病毒宫内传播机制研究进展

慢性乙型肝炎病毒（hepatitis B virus,HBV）感染者中母婴传播占50%以上,围生期HBV感染者90%以上会发展为慢性携带者,且有较高肝硬化和（或）肝癌的发生风险。宫内感染是乙型肝炎疫苗+乙型肝炎免疫球蛋白联合免疫失败致HBV母婴传播的主要原因。HBV宫内感染途径有生殖细胞感染、经胎盘屏障渗漏、经胎盘细胞感染及外周血单个核细胞（peripheral blood mononuclear cell,PBMC）4种途径。HBV可感染穿越胎盘屏障各细胞层尤其是滋养细胞层,其通过胞内囊泡转运系统穿越滋养细胞,多种细胞因子如白细胞介素等可调节HBV感染滋养细胞,诱导滋养细胞磷脂酰肌醇3激酶/磷酸化蛋白激酶B（phosphatidylinositol 3-kinase/phospho protein kinase B,PI3K/pAKT）和Smad信号通路、表皮生长因子受体（epidermal growth factor receptor,EGFR）/AKT信号通路激活及细胞凋亡减少,从而增加HBV母婴传播风险。对血HBV-DNA>2×10⁵ IU/mL孕妇,妊娠24~28周后可以给予口服替诺福韦抗病毒治疗降低HBV母婴传播风险。     

The Transmission of Trauma from Mother to Infant: Radioactive Residues and Counter-Transference in the Case of a Haitian Mother and Her Two-Year-Old Son*

ABSTRACT

Close observation of the interactions between a traumatised mother and her infant son provides information on the modes of transmission of psychic trauma in the mother–infant dyad. Following the presentation of a current literature review on the theme, the subject of “radioactive residue” and counter-transference in the transmission of psychic trauma from mother to infant will be illustrated through a clinical case study that focuses on a Haitian mother and her two-year-old infant son who has been referred to a “transitional care nursery” in urban Paris. The encounter with this mother–infant dyad is analysed through observing the quality of the interactions that take place between the mother and infant in order to determine how a particularly traumatic narrative impacts the mother–infant relationship, in addition to relations with the clinician. Mother and infant respond to one another through the emission and reception of “radioactive residues” as hypothesized by Gampel. This clinical case study shows that there is a need to consider transcultural factors and collective experience and history when analysing traumatic events. Additionally, the case study shows that counter-transference can be an effective clinical tool for gaining access to an infant's experience as the recipient of a traumatic narrative.     

基于指按法及针刺作用于手三里的痛温觉诱发电位探讨经络小纤维神经感传效应

目的观察比较指按法、针刺及痛温觉诱发电位(CHEPs)刺激器作用于正常人手三里产生的CHEPs,探析经络理论的小纤维神经感传方式。方法纳入16名健康成年志愿者,检测指按法、针刺、CHEPs刺激器作用于手三里产生的CHEPs,进行自身前后对照。结果3种刺激手段作用于受试者手三里均可记录到CHEPs,指按法诱发的N波潜伏期比CHEPs刺激器高120.69 ms(P<0.05),针刺诱发的N波潜伏期比CHEPs刺激器高183.69 ms(P<0.001)。指按法诱发的P波潜伏期比CHEPs刺激器高149.13 ms(P<0.05),针刺诱发的P波潜伏期比CHEPs刺激器高215.69ms(P<0.001),指按法和针刺N、P波潜伏期比较差异无统计学意义(P>0.05)。未见不同刺激手段对N、P波幅存在显著主效应(F=0.424,P=0.658;F=1.289,P=0.290)。结论指按法、针刺均可诱发由小纤维介导的N、P波,且通过与CHEPs刺激器诱发电位比较,指按法及针刺传导的小纤维速度更慢,为无髓鞘的C纤维;指按法、针刺诱发的N、P波波幅改变无明显差异。     

Endogenous cannabinoids mediate the effect of BDNF at CA1 inhibitory synapses in the hippocampus

Brain‐derived neurotrophic factor (BDNF), traditionally known for promoting neuronal growth and development, is also a modulator of synaptic transmission. In addition to the well‐characterized effects at excitatory synapses, BDNF has been shown to acutely suppress inhibitory neurotransmission; however, the underlying mechanisms are unclear. We have previously shown that at inhibitory synapses in layer 2/3 of the somatosensory cortex, BDNF induces the mobilization of endogenous cannabinoids (eCBs) that act retrogradely to suppress GABA release. Here, we hypothesized that in the hippocampus, BDNF acts similarly via eCB signaling to suppress GABAergic transmission. We found that the acute application of BDNF reduced the spontaneous inhibitory postsynaptic currents (sIPSCs) via postsynaptic TrkB receptor activation. The suppressive effects of BDNF required eCB signaling, as this effect on sIPSCs was prevented by a CB1 receptor antagonist. Further, blocking the postsynaptic eCB release prevented the effect of BDNF, whereas eCB reuptake inhibition enhanced the effect of BDNF. These results suggest that BDNF triggers the postsynaptic release of eCBs. To identify the specific eCB release by BDNF, we tested the effects of disrupting the synthesis or degradation of 2‐arachidonoylcglycerol (2‐AG). Blocking 2‐AG synthesis prevented the effect of BDNF and blocking 2‐AG degradation enhanced the effect of BDNF. However, there was no change in the effect of BDNF when anandamide degradation was blocked. Collectively, these results suggest that in the hippocampus, BDNF‐TrkB signaling induces the postsynaptic release of the endogenous cannabinoid 2‐AG, which acts retrogradely on the presynaptic CB1 receptors to suppress GABA release.     

Forward and Reverse Middle Ear Transmission in Gerbil with a Normal or Spontaneously Healed Tympanic Membrane

Tympanic membranes (TM) that have healed spontaneously after perforation present abnormalities in their structural and mechanical properties; i.e., they are thickened and abnormally dense. These changes result in a deterioration of middle ear (ME) sound transmission, which is clinically presented as a conductive hearing loss (CHL). To fully understand the ME sound transmission under TM pathological conditions, we created a gerbil model with a controlled 50% pars tensa perforation, which was left to heal spontaneously for up to 4 weeks (TM perforations had fully sealed after 2 weeks). After the recovery period, the ME sound transmission, both in the forward and reverse directions, was directly measured with two-tone stimulation. Measurements were performed at the input, the ossicular chain, and output of the ME system, i.e., at the TM, umbo, and scala vestibuli (SV) next to the stapes. We found that variations in ME transmission in forward and reverse directions were not symmetric. In the forward direction, the ME pressure gain decreased in a frequency-dependent manner, with smaller loss (within 10 dB) at low frequencies and more dramatic loss at high frequency regions. The loss pattern was mainly from the less efficient acoustical to mechanical coupling between the TM and umbo, with little changes along the ossicular chain. In the reverse direction, the variations in these ears are relatively smaller. Our results provide detailed functional observations that explain CHL seen in clinical patients with abnormal TM, e.g., caused by otitis media, that have healed spontaneously after perforation or post-tympanoplasty, especially at high frequencies. In addition, our data demonstrate that changes in distortion product otoacoustic emissions (DPOAEs) result from altered ME transmission in both the forward and reverse direction by a reduction of the effective stimulus levels and less efficient transfer of DPs from the ME into the ear canal. This confirms that DPOAEs can be used to assess both the health of the cochlea and the middle ear.     

通鼻消涕颗粒对慢性鼻窦炎鼻黏膜功能的影响*

目的对医院制剂通鼻消涕颗粒对慢性鼻窦炎鼻黏膜功能是否有调控作用进行临床研究。方法 收集慢性鼻窦炎不伴鼻息肉患者，采用单盲方法随机将患者分为治疗组（通鼻消涕颗粒组）和对照组（克拉霉素片组）。分别给予口服通鼻消涕颗粒和克拉霉素片治疗4周，并对治疗前、治疗2周后、治疗4周后的患者进行糖精试验、鼻部症状VAS评分与鼻内镜Lund Kennedy评分。并采用t检验统计分析。比较服药前、服药后的评分变化。结果 VAS评分提示：治疗组中，治疗2周后、治疗4周后与治疗前相比差异均有统计学意义（P＜0.05），对照组在治疗后的各个阶段与治疗前相比均无明显差异（P＞0.05）。Lund Kennedy评分提示：治疗组在治疗2周后与治疗前无明显差异，但在治疗4周后有明显改善（P＜0.05），对照组则在治疗后各个阶段无明显变化（P＞0.05）。糖精试验提示2组在治疗后2周患者糖精清除时间差异无统计学意义（P＞0.05），但治疗组在治疗4周后患者糖精清除时间低于对照组（P＜0.05）。结论 通鼻消涕颗粒对慢性鼻窦炎的鼻黏膜形态与传输功能有明显改善作用，可以促进鼻黏膜纤毛功能的恢复，并优于克拉霉素片组，且无毒副作用，值得临床上推广应用。     

Feed or feed transport as a potential route for a porcine epidemic diarrhoea outbreak in a 10,000-sow breeding herd in Mexico

Porcine epidemic diarrhoea virus (PEDV) infects pigs of all ages causing vomiting and diarrhoea. PEDV is transmitted via the oral–faecal route, and a very low dose is enough to infect susceptible pigs, resulting in significant production losses. This short communication aims to describe the introduction of PEDV into a 10,000-sow farrow-to-wean farm located in northwest Mexico. Following the onset of clinical signs, an outbreak investigation was conducted to determine the most probable route of introduction. Based on data collected from interviews, construction of a timeline of events, and the detection of PEDV RNA in feed samples and samples collected from various surfaces of feed transport vehicles, it was concluded that the most probable route for PEDV incursion into this breeding herd was contaminated feed or a contaminated feed transport vehicle. This paper describes how feed or feed transport could serve as potential routes of PEDV infection to a farm and highlights the importance of establishing biosecurity programs to mitigate these risks.     

内镜柔性器械腱鞘传动模型及实验研究

目的 建立内镜柔性器械腱鞘系统的推力传动模型，研究影响传动效率的关键因素。方法 建立腱鞘系统在器械推送作用下力和位移的传动模型并进行仿真计算；搭建腱鞘系统传动测试的实验平台以验证模型的准确性，研究传动速度、腱鞘直径比、弯曲半径等对传动效率的影响。结果 腱鞘传动过程中存在显著的非线性传递现象，传动模型仿真与实验结果基本符合；传动速度、腱鞘直径比、弯曲半径均对内镜柔性器械的推力传动有较大影响，对位移传动的影响相对小一些。结论 该模型可用于内镜柔性器械中腱鞘系统推力传动的计算，提供给医生器械工作末端的力反馈，以保证器械的安全操作和提高手术效果；在内镜柔性器械的精准控制中需要综合考虑传动速度、腱鞘传动比、弯曲半径等对运动传递的影响。