TAXONOMY, MYCOGEOGRAPHY AND ECTO-MYCORRHIZAL ASSOCIATION OF THE BOLETALES FROM CHINA I．FAMILY STROBILOMYCETACEAE

More thart 231 species belonging to the families Strobilomycetaceae and Boletazeae are reported in China There are 4 genem of the family S~obilomycetaceae known from China_The list is based ott herbarium specimens and lileratttre．48 taxa are listed with collectors,data and localities,mycogeogmphic distribution and mycorrhizal association∽diseussed A key to genera is provided     

Issues and opportunities of stem cell therapy in autoimmune diseases

The purpose of regenerative medicine is to restore or enhance the normal function of human cells, tissues, and organs. From a clinical point of view, the use of stem cells is more advantageous than differentiated cells because they can be collected more easily and in larger quantities, their proliferation capacity is more pronounced, they are more resistant in cell culture, their aging is delayed, they are able to form a number of cell lines, and they are able to promote vascularization of tissue carriers. The therapeutic use of stem cells for disease modification, immunomodulation, or regenerative purposes are undoubtedly encouraging, but most studies are still in their early stages, and the clinical results reported are not clear with regard to therapeutic efficacy and potential side effects. Uniform regulation of the clinical application of stem cells is also indispensable for this highly customizable, minimally invasive, individualized therapeutic method to become a successful and safe treatment alternative in many different autoimmune and autoinflammatory disorders.     

New species of the isolated Psaroniaceous rachis from the Early Permian in China

A new kind of marattialean raches are reported from the coal balls in Coal Seam No.7 in the upper part of the Taiyuan Formation （early Early Permian） from Taiyuan, Shanxi, China and are assigned to the genus Stipitopteris Grand＇Eury （Psaroniaceae）. The present specimens are different from all six reported species of the genus, and are therefore proposed as a new species： Stipitopteris shanxiensis. The raches of the new species are generally dorsi-ventrally flattened. The main raches usually exhibit scales of different forms on their surface. Beneath the epidermis is a zone of parenchymatous cells, some of which contain tannin-like contents. Inside this is a zone of small sclerenchymatous cells. Inward are the ground tissue and vascular bundles. The vascular bundles are continuous and are in two circles： the outer circle assumes a transversely elliptical shape with the gap and pinna trace, and the inner circle assumes a shallow C.shape with inrolled ends. The ground tissue located at the inner side of the vascular bundle is composed of thicker-walled parenchymatous cells. The cells of the ground tissue are vertically elongated in longitudinal sections. Subordered raches are smaller and have simpler structures than the main raches. The parenchyma zone beneath the epidermis is thinner, usually one to two cells wide and the sclerenchyma zone is usually absent. The scales are poorly developed and there is only one C-shaped vascular bundle. The new species is comparable to the crosiers of Psaroniaceae of the Euramerican Flora in some aspects, for example, it has a dorsi-ventrally flattened rachis and scales on the surface of the rachis. However, the other features and the preservative conditions of the present specimens indicate that they are not crosiers, but fully developed or mature raches. The new species is the first well-studied anatomically-preserved rachis of Psaroniaceae from the Cathaysian Flora and bears significance not only in understanding the anatomy and taxonomy of Psaroniaceae in the Cathaysian Flora, but also in the relationship between the Euramerican Flora and the Cathaysian Flora.     

An emerging hemorrhagic fever in China caused by a novel bunyavirus SFTSV

Severe fever with thrombocytopenia syndrome(SFTS) is an emerging hemorrhagic fever in rural areas of China and is caused by a new bunyavirus,SFTSV,named after the disease.The transmission vectors and animal hosts of SFTSV are unclear.Ticks are the most likely transmission vectors and domestic animals,including goats,dogs,and cattle,are potential amplifying hosts of SFTSV.The clinical symptoms of SFTS are nonspecific,but major symptoms include fever,gastrointestinal symptoms,myalgia,dizziness,joint pain,chills,and regional lymphadenopathy.The most common abnormalities in laboratory test results are thrombocytopenia(95%),leukocytopenia(86%),and elevated levels of serum alanine aminotransferase,aspartate aminotransferase,creatine kinase,and lactate dehydrogenase.The fatality rate for SFTS is 12% on average,and the annual incidence of the disease is approximately five per 100000 of the rural population.     

FISH FAUNA OF THE HWAJINPO LAKE,KOREA

There are sevenlagoons onthe east coast of Korea,including Kyeongpo Lake,Hyang Lake,Mae Lake,Chung-cho Lake,Yeoungrang Lake,Songji Lake and HwajinpoLake.They are all originally natural and brackish waterlakes.Therefore,these lakes are not only historically veryimportant but also have high values for geological,andecological sciences.Natural lakes like lagoons are different from man-made lakes.That is,water level in natural lakes is almostconstant,cline by waterside is not much,and wet la…     

韩国华津浦湖的鱼类区系

There are sevenlagoons onthe east coast of Korea,including Kyeongpo Lake,Hyang Lake,Mae Lake,Chung-cho Lake,Yeoungrang Lake,Songji Lake and HwajinpoLake.They are all originally natural and brackish waterlakes.Therefore,these lakes are not only historically veryimportant but also have high values for geological,andecological sciences.Natural lakes like lagoons are different from man-made lakes.That is,water level in natural lakes is almostconstant,cline by waterside is not much,and wet la…     

Characterization of MR-1, a novel myofibrillogenesis regulator in human muscle

Myofibrils are components of both cardiac and skeletalmuscle cells. Myofibrillogenesis is a highly complexprocess that involves the expression and assembly ofmuscle proteins into sarcomeres [1]. The key componentsof sarcomeres are two filamentary proteins, actin andmyosin. Sarcomeric myosin is the molecular motor thattransduces energy from the hydrolysis of ATP into directedmovement and drives sarcomere shortening and musclecontraction. Each myosin hexamer is composed of twoheavy chains, two…     

Thoughts of a travelling ecologist 17.One biosecurity

The still-untamed SARS-CoV-2 pandemic underlined,again,two important facts that have been known for a long while but conveniently forgotten by humankind.One is that we are profoundly linked to other organisms and nature,and the other is that human-driven distribution chains are global and fast.     

Asymptotic analysis of a mat hematical model of the atherosclerosis development

A mathematical model,which takes into account new experimental results about diverse roles of macrophages in the atherosclerosis development,is proposed.Using technic of upper and lower solutions,the existence and uniqueness of its positive solution are justified.After the nondimensionalization,small parameters are found and the multiscale analysis of the corresponding perturbed problem is performed when those parameters tend to zero.In particular,the limit two-dimensional problem,which is a coupled system of reaction-diffusion equations and ordinary differential equations,is derived;the asymptotic approximation is constructed;the uniform pointwise estimate for the difference between the solution of the original problem and the solution of the limit problem as well as the respective L^2-estimates for the fluxes are proved.     

C-Type natriuretic peptide modulates pre- and postsynaptic properties in hippocampal area CA1 in vitro

The cGMP producing natriuretic peptide receptor B (NPR-B) and its ligand C-type natriuretic peptide (CNP) are widely distributed in the brain and are highly expressed in the hippocampal regions CA1-CA3. To date only limited functional data is available concerning the physiological effects of the peptide hormone in the hippocampus. Therefore, we were interested in how bath application of the peptide hormone might influence synaptic plasticity following high frequency stimulation (HFS). We found that CNP application decreased the population spike (PS) amplitude after HFS, thereby affecting long-term potentiation (LTP) in acute hippocampal slices. To investigate the molecular consequences of CNP application leading to a decrease in PS amplitude, we further analyzed the impact of the hormone on the number of presynaptic synapsin I clusters and number of postsynaptic AMPA receptor subunit GluR1 clusters as well as their co-localization in a primary hippocampal cell culture system. The observed pre-and postsynaptic effects after CNP stimulation of the cGMP pathway in hippocampal cell cultures may underlie the effect of the peptide hormone on LTP.     

脑发育不同阶段慢性铅暴露对大鼠在体海马齿状回LTP的影响

目的和方法：探讨脑发育不同阶段慢性铅暴露对在体海马ＬＴＰ的影响。应用细胞外微电极记录单脉冲刺激穿通路纤维在海马齿状回诱发的群体锋电位（ＰＳ）,观察母体期、断乳后及出生前后持续性慢性铅暴露大鼠于高频刺激（ＨＦＳ）前后的ＰＳ幅值变化,并与对照组相比较。结果：ＨＦＳ前,基线记录的各铅暴露组ＰＳ平均幅值及峰潜伏期与对照组无显著差异;ＨＦＳ后,各铅暴露组ＬＴＰ发生率虽与对照组无显著差异,但铅暴露组的ＬＴＰ增幅减小,并出现了短时增强转为抑制及ＬＴＤ型反应。统计显示各铅暴露组ＨＦＳ后ＰＳ振幅的平均增强率显著低于对照组：对照组平均增强至基线值的１３８．２％,母体期铅暴露组为基线值的１０８．８％,断乳后铅暴露组为基线值的１０７．８％,持续铅暴露组为基线值的１０４．４％。结论：脑发育任一阶段的慢性铅暴露均可损害海马ＬＴＰ的在体诱导和维持,且以维持过程受损为主;与发育成熟海马相比,未成熟期海马对铅的神经毒性更为敏感,突触可塑性更易受损。     

Hippocampal Long-Term Potentiation Attenuated by Lesions in the Marginal Division of Neostriatum

The marginal division (MrD) is a spindled-neurons consisted zone at the caudal border of the neostriatum in the mammalian brain and has been verified as contributing to associative learning and declarative memory in the rat and human with behavior and functional magnetic resonance imaging methods. It was proved to have functional connections with the limbic system. Whether the MrD has influence on the hippocampal long-term potentiation (LTP) was investigated in this study. LTP was induced from the dentate gyrus (DG) in the hippocampus by high-frequency stimulation (HFS) to the perforant path (PP). The amplitude of the population spike (PS) and the slope of the excitatory postsynaptic potential (EPSP) increased significantly to form LTP in the DG of the hippocampus after HFS of PP in normal and saline-injected control groups of rats. Lesions introduced in the MrD reduced significantly both the amplitude of PS and the slope of the EPSP following HFS of the PP. The results indicated that lesions in the MrD could attenuate LTP formation in the hippocampus. Our data suggest that the MrD might very possibly have excitatory functional influence on the hippocampus and therefore might influence the function of the hippocampus.     

小鼠海马CAl区高频刺激诱发的突触可塑性分析

通过细胞外记录方法记录场兴奋性突触后电位（field excitatory postsynaptic potential,fEPSP）的变化是研究突触可塑性,诸如长时程增强（long-term potentiation,LTP）和双脉冲可塑性（paired-pulse plasticity,PPP）的最常见方法之一。fEPSP波形的起始斜率、起始面积、峰值及总面积等的变化常用作判断突触可塑性增强或减弱的标准。在相同记录结果中测量fEPSP波形不同部位通常会有不同的结果,因此可能得出不同的结论,这些往往会被研究者忽略。本文通过测量小鼠海马CA1区细胞fEPSP波形的起始斜率、起始面积、峰值、总面积及时间参数等,分析比较高频刺激（high-frequency stimulation,HFS）诱发的突触可塑性,包括LTP和PPP的变化。结果显示,LTP过程中AMPA受体动力学变化加快,且在同一记录中,fEPSP波形不同部位的测量分析可以产生较大幅度的LTP和PPP差异。给予HFS后,双脉冲诱发fEPSP的比率在测量起始面积时略有下降,但在测量起始斜率时则显著增加,这些结果可能导致相反的结论。因此,全面仔细地分析fEPSP波形在整个实验中的变化对正确了解突触可塑性至关重要。     

Eugenol depresses synaptic transmission but does not prevent the induction of long-term potentiation in the CA1 region of rat hippocampal slices

Using field potential recording in the CA1 region of the rat hippocampal slices, the effects of eugenol on synaptic transmission and long-term potentiation (LTP) were investigated. Population spikes (PS) were recorded in the stratum pyramidal following stimulation of stratum fibers. To induce LTP, eight episodes of theta pattern primed-bursts (PBs) were delivered. Eugenol decreased the amplitude of PS in a concentration-dependent manner. The effect was fast and completely reversible. Eugenol had no effect on PBs-induced LTP of PS. It is concluded that while eugenol depresses synaptic transmission it does not affect the ability of CA1 synapses for tetanus-induced LTP and plasticity.     

Circadian regulation of hippocampal long-term potentiation

The goal of this study is to investigate the possible circadian regulation of hippocampal excitability and long-term potentiation (LTP) measured by stimulating the Schaffer collaterals (SC) and recording the field excitatory postsynaptic potential (fEPSP) from the CA1 dendritic layer or the population spike (PS) from the soma in brain slices of C3H and C57 mice. These 2 strains of mice were of interest because the C3H mice secrete melatonin rhythmically while the C57 mice do not. The authors found that the magnitude of the enhancement of the PS was significantly greater in LTP recorded from night slices compared to day slices of both C3H and C57 mice. They also found significant diurnal variation in the decay of LTP measured with fEPSPs, with the decay slower during the night in both strains of mice. There was evidence for a diurnal rhythm in the input/output function of pyramidal neurons measured at the soma in C57 but not C3H mice. Furthermore, LTP in the PS, measured in slices prepared during the day but recorded during the night, had a profile remarkably similar to the night group. Finally, PS recordings were carried out in slices from C3H mice maintained in constant darkness prior to experimentation. Again, the authors found that the magnitude of the enhancement of the PS was significantly greater in LTP recorded from subjective night slices compared to subjective day slices. These results provide the 1st evidence that an endogenous circadian oscillator modulates synaptic plasticity in the hippocampus.     

钩藤对致痫大鼠海马脑片诱发场电位的影响

目的研究钩藤对癫痫模型海马脑片诱发场电位的影响。方法以毛果芸香碱致痫大鼠为实验对象,采用脑片旁滴注给药,用细胞外玻璃微电极记录方法,观察钩藤对癫痫模型离体海马脑片CA1区锥体细胞诱发群锋电位（populationspike,PS）的影响。结果给予钩藤后使致痫大鼠海马脑片PS幅度平均降低27.64％,平均8.71min恢复(n=14,P<0.01)。结论钩藤能降低致痫大鼠海马脑片CA1区顺向诱发PS幅度,提示钩藤对中枢神经系统的突触传递过程有明显的抑制效应,具有抗癫痫作用。     

双电极绑定技术记录在体大鼠海马CA1区长时程增强

目的:探讨双电极绑定条件下记录大鼠在体海马CA1区长时程增强的可行性。方法:雄性Wistar大鼠乌拉坦麻醉;脑立体定位仪上埋置脑室导管;安装自制的刺激/记录绑定电极;引导基础性场兴奋性突触后电位(fEP-SP);强直刺激诱导长时程增强(LTP)。结果:绑定后的刺激和记录电极能可靠地引起海马CA1区fEPSP,fEPSP的出现率几乎100%;基础性fEPSP记录可保持长时间稳定;高频刺激成功诱导出LTP并维持达3h以上,诱导率约67%;双脉冲易化记录稳定、可靠;脑室注射β淀粉样蛋白(Aβ)对LTP显示出明显的压抑作用。结论:采用双电极绑定技术进行在体海马LTP记录简便易行、节省资源、引导fEPSP和诱导LTP的成功率较高,有望成为一项重要的研究学习和记忆机制的电生理辅助手段。     

Maternal infection and fever during late gestation are associated with altered synaptic transmission in the hippocampus of juvenile offspring rats

Prenatal exposure to infection is known to affect brain development and has been linked to increased risk for schizophrenia. The goal of this study was to investigate whether maternal infection and associated fever near term disrupts synaptic transmission in the hippocampus of the offspring. We used LPS to mimic bacterial infection and trigger the maternal inflammatory response in near-term rats. LPS was administered to rats on embryonic days 15 and 16 and hippocampal synaptic transmission was evaluated in the offspring on postnatal days 20-25. Only offspring from rats that showed a fever in response to LPS were tested. Schaffer collateral-evoked field excitatory postsynaptic potentials (fEPSPs) and fiber volleys in CA1 of hippocampal slices appeared smaller in offspring from the LPS group compared with controls, but, when the fEPSPs were normalized to the amplitude of fiber volleys, they were larger in the LPS group. In addition, intrinsic excitability of CA1 pyramidal neurons was heightened, as antidromic field responses in the LPS group were greater than those from control. Short-, but not long-term plasticity was impaired since paired-pulse facilitation of the fEPSP was attenuated in the LPS group, whereas no differences in long-term potentiation were noted. These results suggest that LPS-induced inflammation during pregnancy produces in the offspring a reduction in presynaptic input to CA1 with compensatory enhancements in postsynaptic glutamatergic response and pyramidal cell excitability. Neurodevelopmental disruption triggered by prenatal infection can have profound effects on hippocampal synaptic transmission, likely contributing to the memory and cognitive deficits observed in schizophrenia.     

Increased expression of phospho-cofilin in CA1 and subiculum areas after theta-burst stimulation of Schaffer collateral-commissural fibers in rat hippocampal slices

Activity-dependent structural plasticity of dendritic spines of pyramidal neurons in the central neuron system has been proposed to be a cellular basis of learning and memory. Long-term potentiation (LTP) is accompanied by changes in synaptic morphology and structural remodeling of dendritic spines. However, there is considerable uncertainty as to the nature of the adjustment. The present study tested whether immunoreactive phospho-cofilin, an index of altered actin filament assembly, could be increased by theta-burst stimulations (TBS), which is an effective stimulation pattern for inducing LTP in the hippocampus. The slope of fEPSPs evoked by TBS to Schaffer collateral-commissural fibers in hippocampal slices was measured, and p-cofilin expression was examined using immunofluorescence techniques. Results indicated that saturated L-LTP was produced by multiple TBS episodes to Schaffer collateral-commissural fibers in the hippocampal CA1 area, and TBSs also increased immunoreactive p-cofilin expression in the stratum radiatum of the hippocampal CA1 area and pyramidal layer of the subiculum. D-2-amino-5-phosphonovalerate (D-APV) prevented LTP and expression of p-cofilin immunoreactive induced by multiple TBS episodes in the stratum radiatum of the hippocampal CA1 area. Two paired-pulse low-frequency stimulation (PP-LFS) episodes to Schaffer collateral-commissural fibers induced long-term depression (LTD), and did not affect p-cofilin expression in the stratum radiatum of the hippocampal CA1 area. These results suggest that LTP induction is associated with altered actin filament assembly. Moreover, the CA1 and subiculum areas of the hippocampal formation possibly cooperate with each other in important physiological functions, such as learning and memory, or in pathological diseases, such as epilepsy.