愈伤涂膜剂对树干伤口灭菌防腐试验

[目的]对黄斑星天牛危害树木后留下的成虫产卵刻槽、羽化孔、幼虫的排粪孔和打孔注药后所造成的孔洞、伤疤、伤流进行修复,利用愈伤涂膜剂进行涂抹试验,并确定涂药量和涂药时间.促使伤口快速愈合,减少伤流和腐烂病发生.[方法]在树木冬眠初期或早春树木萌动前,将愈伤涂膜剂均匀地涂抹在树干伤口上,以涂满伤疤为宜.[结果]该药剂除了对50 a以上的树木伤口愈合率低外,对其它树木愈伤效果很明显,伤口愈合率可达58.6;,伤流株率下降了41.2;;腐烂病也可降低92.7;.[结论]愈伤涂膜剂在树干伤口上不但能够迅速形成具有透气性强的保护膜,起到封闭、阻隔作用,防止树液流失,而且还具有灭菌防腐,促进愈伤组织的再生能力.     

EGFR activation mediates inhibition of axon regeneration by myelin and chondroitin sulfate proteoglycans

Inhibitory molecules associated with myelin and the glial scar limit axon regeneration in the adult central nervous system (CNS), but the underlying signaling mechanisms of regeneration inhibition are not fully understood. Here, we show that suppressing the kinase function of the epidermal growth factor receptor (EGFR) blocks the activities of both myelin inhibitors and chondroitin sulfate proteoglycans in inhibiting neurite outgrowth. In addition, regeneration inhibitors trigger the phosphorylation of EGFR in a calcium-dependent manner. Local administration of EGFR inhibitors promotes significant regeneration of injured optic nerve fibers, pointing to a promising therapeutic avenue for enhancing axon regeneration after CNS injury.     

微血管周细胞与糖尿病视网膜病变中西医研究进展

大量的实验研究已经证实,微血管周细胞在糖尿病视网膜病变早期防治中扮演重要角色。为了观察和研究糖尿病视网膜病变早期微血管周细胞结构和功能变化,本文对近些年微血管周细胞的起源、形态分布、生理功能、细胞培养与鉴定、周细胞凋亡与糖尿病视网膜病变关系以及中医药防治糖尿病视网膜病变的研究进展进行综述,以期为糖尿病视网膜病变的周细胞研究及早期防治提供一种新思路。     

结缔组织生长因子在增生性瘢痕成纤维细胞中的表达

目的 :探讨结缔组织生长因子 (CTGF)在人类增生性瘢痕成纤维细胞中的表达与瘢痕纤维化之间的关系。方法 :应用半定量逆转录聚合酶链反应 (RT- PCR)和 Western blot技术 ,检测了瘢痕组织原代培养的成纤维细胞中 CTGFm RNA及蛋白表达。结果 :CTGF m RNA及蛋白在人类增生性瘢痕成纤维细胞中高度表达 ,与正常皮肤组织的成纤维细胞比较 ,差异有显著性意义 (P<0 .0 1)。结论 :CTGF在人类增生性瘢痕成纤维细胞中呈高度表达 ,提示其在增生性瘢痕的纤维化进程中起着重要的作用 ,这为临床上寻找安全、有效的治疗增生性瘢痕药物提供了可能。     

Astrocytic purinergic signaling coordinates synaptic networks

To investigate the role of astrocytes in regulating synaptic transmission, we generated inducible transgenic mice that express a dominant-negative SNARE domain selectively in astrocytes to block the release of transmitters from these glial cells. By releasing adenosine triphosphate, which accumulates as adenosine, astrocytes tonically suppressed synaptic transmission, thereby enhancing the dynamic range for long-term potentiation and mediated activity-dependent, heterosynaptic depression. These results indicate that astrocytes are intricately linked in the regulation of synaptic strength and plasticity and provide a pathway for synaptic cross-talk.     

小麦品种对赤霉病的抗性

小麦品种对赤霉病的抗性主要表现在抗病害扩展,而不是抗病菌侵入。抗病品种的特点是病害自侵染点向邻近小穗扩展速度慢,穗轴受害轻或不受害,病小穗数少;在感病品种上,病害扩展速度快,可导致全穗枯萎。不同抗性品种对真菌毒素的敏感程度不一,抗病品种耐毒力强,细胞膜损伤程度轻,胞内电解质外漏量少;这种电解质外漏量间的差异,可采用电导仪测定组织侵出液的电导率而加以确定。     

Neural activity triggers neuronal oxidative metabolism followed by astrocytic glycolysis

We have found that two-photon fluorescence imaging of nicotinamide adenine dinucleotide (NADH) provides the sensitivity and spatial three-dimensional resolution to resolve metabolic signatures in processes of astrocytes and neurons deep in highly scattering brain tissue slices. This functional imaging reveals spatiotemporal partitioning of glycolytic and oxidative metabolism between astrocytes and neurons during focal neural activity that establishes a unifying hypothesis for neurometabolic coupling in which early oxidative metabolism in neurons is eventually sustained by late activation of the astrocyte-neuron lactate shuttle. Our model integrates existing views of brain energy metabolism and is in accord with known macroscopic physiological changes in vivo.     

梨瘿螨为害梨叶特性及螨瘿组织形态结构

梨瘿螨(Eriophyes pyri Pagenstecher)为害梨叶后,叶背面产生淡绿色小疱疹,梨树叶片形态结构发生改变。为害初期,叶片上出现浅绿色小斑点;叶片受害部位海绵组织细胞增生,逐渐向叶背隆起,螨瘿开始形成,并不断扩大,此时,栅栏组织不受影响;螨瘿停止增大后,瘿内海绵组织细胞开始离析、解体,栅栏组织发生异常,而后受害部位逐渐变黑坏死。     

硅凝胶在治疗瘢痕的应用研究进展

硅凝胶是聚二甲基硅氧烷单链通过乙烯基键桥相互交联及长链之间的相互缠绕而构成的网状结构化合物.硅凝胶干燥后在瘢痕表面形成的保护膜具有良好的透气性和散热作用,极大降低了瘢痕因闷湿引发感染的风险.文章阐述了硅凝胶及硅凝胶联合疗法治疗瘢痕的临床案例,总结了目前硅凝胶防治瘢痕的机制,并对将来硅凝胶治疗瘢痕的应用方向提出了展望.     

The Hedgehog pathway promotes blood-brain barrier integrity and CNS immune quiescence

The blood-brain barrier (BBB) is composed of tightly bound endothelial cells (ECs) and perivascular astrocytes that regulate central nervous system (CNS) homeostasis. We showed that astrocytes secrete Sonic hedgehog and that BBB ECs express Hedgehog (Hh) receptors, which together promote BBB formation and integrity during embryonic development and adulthood. Using pharmacological inhibition and genetic inactivation of the Hh signaling pathway in ECs, we also demonstrated a critical role of the Hh pathway in promoting the immune quiescence of BBB ECs by decreasing the expression of proinflammatory mediators and the adhesion and migration of leukocytes, in vivo and in vitro. Overall, the Hh pathway provides a barrier-promoting effect and an endogenous anti-inflammatory balance to CNS-directed immune attacks, as occurs in multiple sclerosis.     

广西鸡源H9N2亚型禽流感病毒分离鉴定及遗传进化分析

[目的]明确广西鸡源H9N2亚型禽流感病毒(AIV)的分子遗传变异规律及其对公共卫生安全的影响,为H9亚型禽流感(AI)的防控提供参考依据.[方法]从广西某肉鸡养殖场采集病料,经SPF鸡胚接种进行病毒分离,对初步鉴定为H9亚型AIV分离株的HA、NA、PB2、PB1、PA、NP、M和NS等8个基因片段进行克隆测定及遗传进化分析,同时对分离毒株的生物学特性进行测定.[结果]从广西发病鸡群中分离获得一株H9N2亚型AIV,命名为A/chicken/Guangxi/BT1/2016(H9N2).分离毒株A/chicken/Guangxi/BT1/2016(H9N2)HA基因的裂解位点为PSRSSR↓GLF,具有典型的低致病性AIV(LPAIV)分子特征,在遗传进化关系上属于4.2.5分支,与国内常用H9N2亚型AIV疫苗株所属的4.2.3分支存在一定差异;其他7个基因也分别来源于不同的AIV亚型.分离毒株A/chicken/Guangxi/BT1/2016 (H9N2)同时具备与α-2,3唾液酸和α-2,6唾液酸受体结合的特性,且具有感染人类的潜在风险;其感染鸡群后病毒分布主要集中在气管、肺脏和脾脏,可通过呼吸道和消化道同时排毒,且在攻毒后第1d即开始排毒,第5d为排毒高峰.[结论]从广西发病鸡群中分离获得的A/chicken/Guangxi/BT1/2016(H9N2)属于LPAIV,是由不同亚型AIV重组产生的H9N2亚型新毒株,可导致鸡群疫苗免疫失败,且具有感染人类的潜在风险.     

Biochemical Tests Indicative of Reaction of Castor Bean to Botrytis

Pectic and cellulolytic enzymes caused browning and maceration of capsules of susceptible varieties of castor bean but not of resistant varieties. Results of tests in which pericarp tissue of the capsule was treated with vanillin and H(2)SO(4) and with an aqueous solution of FeCl(3) and K(3)Fe(CN)(6) showed that resistance to the hydrolytic enzymes was correlated with both a low concentration of flavanols and related compounds and the presence of oxidized compounds in injured tissue. Resistance appeared to be due to inactivation of pectic, cellulolytic, and other hydrolytic enzymes by oxidation products of phenolic compounds. The biochemical tests made rapid measurement of resistance possible.     

链杆式升运器薯土分离损伤机理研究

4GS-1500型甘薯收获机采用链杆式升运器作为输送分离装置,是杆条升运链式甘薯收获机的典型代表机具。为改进链杆式升运器设计、减小输送分离和抛薯过程中对甘薯的损伤,以商薯19、阜薯24、郑薯20为对象,采用配置了链杆式升运器的4GS-1500型甘薯收获机进行甘薯收获试验,运用力学、运动学等原理,结合试验分析,研究链杆式升运器在输送分离、抛薯过程中产生损伤的原因和减小损伤率的措施。结果表明:配置了链杆式升运器的4GS-1500型甘薯收获机主要损伤形式为表面擦伤,同时伴有压损、薯肉缺损、断裂等特征。损伤主要由输送分离时土块、甘薯、链杆等对甘薯挤压、冲击、摩擦以及抛薯时甘薯撞击地面所产生的冲击造成。通过优化链杆式升运器的设计参数和运行参数,甘薯损伤率降至约1.5%。     

Specification and morphogenesis of astrocytes

Astrocytes are the most abundant cell type in the mammalian brain. Interest in astrocyte function has increased dramatically in recent years because of their newly discovered roles in synapse formation, maturation, efficacy, and plasticity. However, our understanding of astrocyte development has lagged behind that of other brain cell types. We do not know the molecular mechanism by which astrocytes are specified, how they grow to assume their complex morphologies, and how they interact with and sculpt developing neuronal circuits. Recent work has provided a basic understanding of how intrinsic and extrinsic mechanisms govern the production of astrocytes from precursor cells and the generation of astrocyte diversity. Moreover, new studies of astrocyte morphology have revealed that mature astrocytes are extraordinarily complex, interact with many thousands of synapses, and tile with other astrocytes to occupy unique spatial domains in the brain. A major challenge for the field is to understand how astrocytes talk to each other, and to neurons, during development to establish appropriate astrocytic and neuronal network architectures.     

骨髓间充质干细胞移植治疗脑缺血的动物实验研究

    探讨骨髓间充质干细胞(MSCs)移植对大鼠脑缺血的修复和治疗.体外分离培养大鼠MSCs,以Hoeschst33342标记,移植到大脑中动脉梗塞(MCAO)模型的大鼠体内,分别设立缺血1 d和缺血7 dMSCs移植组与缺血对照组,对各组大鼠进行神经功能损害严重程度评分(NSS)及大脑组织切片观察比较.结果发现,缺血1 d MSCs移植组大鼠NSS评分低于另外两组,差异显著(P＜0.05),大脑组织结构清晰、完整,胶质瘢痕少;缺血7 d MSCs移植组与对照组无明显差异(P＞0.05).故缺血早期进行MSCs移植,大鼠神经功能恢复情况明显.MSCs在损伤后的脑组织内能够存活并且分化为神经元、胶质细胞等,对动物神经损伤后组织重建及功能恢复有一定的治疗作用.     

Wounding and its role in RSV-mediated tumor formation

Tumors induced in chickens by Rous sarcoma virus remain localized at the site of injection even though the animals become viremic. Tumors have now been shown to be inducible at other sites if a wound is inflicted or if the tissue is injured by administration of tumor promoters. These findings indicate that local wounding plays a role in the spread of tumorigenicity of Rous sarcoma virus.     

基于越橘南高丛与北高丛正反交群体的果实贮藏相关性状筛选及其遗传倾向

【目的】筛选与越橘果实贮藏性相关的性状并揭示其遗传规律,为越橘果实贮藏性改良育种提供依据。【方法】调查越橘果实的果蒂痕大小、果实硬度、可溶性固形物含量、酸含量、果实重量、果型指数、贮藏性等7个性状,通过相关性分析和主成分分析筛选与贮藏性相关的主要性状,利用正反交群体分析其遗传倾向。【结果】相关性分析和主成分分析结果表明,越橘果实贮藏性与果蒂痕性状呈极显著负相关（P<0.001）,与果实硬度性状呈极显著正相关（P<0.01）,二者是与蓝莓贮藏性相关的主要性状。越橘果实带柄和脱柄贮藏试验表明果蒂痕大小对越橘果实贮藏有重要影响。果蒂痕大小和果实硬度性状在正、反交群体中呈正态分布,表现为多基因控制的数量性状,变异系数均大于15%。正、反交群体果蒂痕大小趋近于亲本平均值,无父母本倾向,其广义遗传力（H²）在正、反交群体中分别为0.887和0.867,其遗传变异主要来自遗传效应,遗传潜能较大。正、反交群体果实硬度平均值均趋于低值亲本,即存在倾向于果实硬度变小的劣质遗传,H²在正、反交组合中分别为0.535和0.514,表明越橘果实硬度遗传效应较小,遗传不稳定,易受环境影响。【结论】越橘果实果蒂痕大小和果实硬度性状与贮藏性密切相关,其中果蒂痕性状呈趋中遗传,其遗传变异主要来自遗传效应,遗传潜能大,超高亲遗传不明显;果实硬度性状遗传受低值亲本影响较大,存在明显的劣质遗传倾向,遗传效应小,受环境影响大。     

Brain region and gene specificity of neuropeptide gene expression in cultured astrocytes

Astrocytes have many neuronal characteristics, such as neurotransmitter receptors, ion channels, and neurotransmitter uptake systems. Cultured astrocytes were shown to express certain neuropeptide genes, with specificity for both the gene expressed and the brain region from which the cells were prepared. Somatostatin messenger RNA and peptides were detected only in cerebellar astrocytes, whereas proenkephalin messenger RNA and enkephalin peptides were present in astrocytes of cortex, cerebellum, and striatum. Cholecystokinin was not expressed in any of the cells. These results support the hypothesis that peptides synthesized in astrocytes may play a role in the development of the central nervous system.     

Glutamate induces calcium waves in cultured astrocytes: long-range glial signaling

The finding that astrocytes possess glutamate-sensitive ion channels hinted at a previously unrecognized signaling role for these cells. Now it is reported that cultured hippocampal astrocytes can respond to glutamate with a prompt and oscillatory elevation of cytoplasmic free calcium, visible through use of the fluorescent calcium indicator fluo-3. Two types of glutamate receptor--one preferring quisqualate and releasing calcium from intracellular stores and the other preferring kainate and promoting surface-membrane calcium influx--appear to be involved. Moreover, glutamate-induced increases in cytoplasmic free calcium frequently propagate as waves within the cytoplasm of individual astrocytes and between adjacent astrocytes in confluent cultures. These propagating waves of calcium suggest that networks of astrocytes may constitute a long-range signaling system within the brain.     

广西野鸟H9N2亚型流感病毒的分离与鉴定

【目的】探讨H9N2亚型流感病毒在野鸟中的存在与传播,为广西流感疫情动态监测和防控及人流感预防监测提供重要依据。【方法】采集广西野鸟肺脏组织,将病料接种于9~11日龄SPF鸡胚尿囊腔进行分离培养,血清学试验鉴定HA和NA亚型,并克隆扩增其HA和NA基因。【结果】该分离株能被H9亚型阳性血清抑制,神经氨酸酶抑制（NI）试验结果将其鉴定为N2亚型,判断该病毒属于H9N2亚型流感病毒,命名为A/wildbird/Guangxi/H2/07,对HA和NA基因进行序列分析,发现与流感病毒H9亚型和N2亚型同源性最高,分别达到82.4%~99.0%和83.1%~99.9%。【结论】H9N2亚型流感病毒已在广西野鸟中存在,该结论为广西流感疫情动态监测和防控提供了重要依据。