二疣犀甲成虫头部感受器超微结构观察

利用扫描电镜对二疣犀甲[Oryctes rhinoceros(Linnaeus)]雌雄成虫的触角、下颚须和下唇须上嗅感器超微结构特征及分布进行研究.结果表明,二疣犀甲(O.rhinoceros)成虫头部存在5种感受器.触角上有3种,以板型感器为主,分布在触角鳃片表皮内陷形成的凹腔里,此外还有毛型感器、腔锥形感器.雌雄成虫触角上感器的分布模式及数量没有明显的区别;下颚须和下唇须存在4种感器,即腔锥形感器、毛型感器、末梢锥形感器、钟型感器,其中末梢锥形感器在下颚须上分布存在性二型现象,其余3种感器在雌、雄二疣犀甲下颚须和下唇须上的分布和数量无明显区别.     

Variation in testicular histology of the spiny tailed lizard Uromastyx aegyptius microlepis during hibernation and active periods

The testicular histology of the lizard, Uromastyx aegyptius microlepis were varied considerably during hibernation and activity periods, reaching maximum values in summer. The onset of winter induces testicular regression, reduced testis size, testis diameter, diameter and epithelial height of the seminiferous tubules and epididymal epithelial height. Animals exhibit testicular recrudescence during late winter (February and March) and maximum testicular volume occurred during June. The period of maximal testicular volume was positively correlated with increasing ambient temperature. The summer season induces the testicular activity in contrast with the winter season in which the activity decreased and the testes were collapsed. Spermatocytogenesis is active in early spring and the major portion of the seminiferous epithelium comprises spermatids in various stages of maturation and their luminae were filled with spermatozoa. The size of the interstitial cells is direct correlated with changes occurring in epididymis and seminiferous epithelium. Most interstitial cell nuclei show clear regression when spermatocytogenesis were diminishes.     

Cytotoxic effect of two legumes in epithelial cells of the small intestine

The previously known high toxicity and hemagglutinin concentration found in Escumite bean (Phaseolous acutifolius), widely consumed in the south-east of Mexico, induced us to study the cytotoxic effect of these beans on the epithelial cells of the small intestine of rats. Another, less toxic leguminosae, chick-pea (Cicer arietinum), was used for comparison. In vitro tests showed that the viability of the cells was much more affected by the Escumite bean extract than by the chick-pea extract (P<0.001). The cellularity was much diminished when the epithelial cells were treated with Escumite extract (P<0.001), but not with chick-pea extract. In vivo experiments confirmed these findings. The present results suggest that the deleterious effect of some toxicants present in the raw legume is due to an interaction with intestinal epithelium, which, in turn, may cause a reduced absorption of nutrients.     

小麦颖果发育和萌发过程中盾片的结构特征

为了进一步明确小麦颖果发育和萌发过程中盾片的结构特征,以扬麦13为材料,采用超薄切片、显微和超微观察及Image-pro Plus软件图像分析等技术,研究了小麦盾片在颖果发育及萌发过程中的结构变化。结果表明,花后16d,颖果靠近胚乳的胚周缘细胞由外到内分别分化为盾片上皮细胞和盾片薄壁细胞。在颖果发育过程中,盾片上皮细胞形态由不规则形转变为细长形,数目逐渐增加,面积逐渐减小。盾片上皮细胞中淀粉粒不断降解,颈部盾片上皮细胞呈细长形,而底部细胞呈多边形和椭圆形。盾片薄壁细胞淀粉粒不断增多,体积变大。花后16~20d细胞液泡化,积累脂质体和植酸钙镁颗粒,细胞核中核染色质明显降解。在萌发过程中,盾片上皮细胞由不规则形和多边形向圆形转变,细胞的数目先减少后增加,面积先增加后呈减小趋势。薄壁细胞内淀粉体不断变形、塌陷并逐渐降解,蛋白体发生解体,而脂质体先降解而后又重新合成。由以上结果说明,小麦盾片具有吸收转运养分、贮藏养分及保护胚等功能。     

腰果树分泌道超微结构的研究

用透射电镜技术研究了腰果树（Ａｎａｃａｒｄｉｕｍ ｏｃｃｉｄｅｎｔａｌｅ Ｌ．）末端小枝次生韧皮部分泌道的结构，着重研究了上皮细胞中的亲锇物质的形成、积累和排出，这些亲锇物质是分泌道的主要产物。观察表明，在充分发育的上皮细胞中，大量亲锇物质出现在细胞质、内质网潴泡和质体中。在细胞质中可以看到大量直径为２０～３０ｎｍ的亲锇的微粒，看来它们能聚集成为大小不等的亲锇物质的团块。这些亲锇物质的团块常常附着     

Tetrodotoxin as a tool to elucidate sensory transduction mechanisms: the case for the arterial chemoreceptors of the carotid body

Carotid bodies (CBs) are secondary sensory receptors in which the sensing elements, chemoreceptor cells, are activated by decreases in arterial PO(2) (hypoxic hypoxia). Upon activation, chemoreceptor cells (also known as Type I and glomus cells) increase their rate of release of neurotransmitters that drive the sensory activity in the carotid sinus nerve (CSN) which ends in the brain stem where reflex responses are coordinated. When challenged with hypoxic hypoxia, the physiopathologically most relevant stimulus to the CBs, they are activated and initiate ventilatory and cardiocirculatory reflexes. Reflex increase in minute volume ventilation promotes CO(2) removal from alveoli and a decrease in alveolar PCO(2) ensues. Reduced alveolar PCO(2) makes possible alveolar and arterial PO(2) to increase minimizing the intensity of hypoxia. The ventilatory effect, in conjunction the cardiocirculatory components of the CB chemoreflex, tend to maintain an adequate supply of oxygen to the tissues. The CB has been the focus of attention since the discovery of its nature as a sensory organ by de Castro (1928) and the discovery of its function as the origin of ventilatory reflexes by Heymans' group (1930). A great deal of effort has been focused on the study of the mechanisms involved in O(2) detection. This review is devoted to this topic, mechanisms of oxygen sensing. Starting from a summary of the main theories evolving through the years, we will emphasize the nature and significance of the findings obtained with veratridine and tetrodotoxin (TTX) in the genesis of current models of O(2)-sensing.     

Gut Organoid as a New Platform to Study Alginate and Chitosan Mediated PLGA Nanoparticles for Drug Delivery

Intestinal organoids can be used as an ex vivo epithelial model to study different drug delivery effects on epithelial cells’ luminal surface. In this study, the impact of surface charge on the delivery of 5-ASA loaded PLGA nanoparticles into the lumen of organoids was investigated. Alginate and chitosan were used to coat the nanoparticles and provide negative and positive charges on the particles, respectively. The organoid growth and viability were not affected by the presence of either alginate- or chitosan-coated nanoparticles. It was shown that nanoparticles could be transported from the serosal side of the organoids to the lumen as the dye gradually accumulated in the lumen by day 2–3 after adding the nanoparticles to the Matrigel. By day 5, the dye was eliminated from the lumen of the organoids. It was concluded that the positively charged nanoparticles were more readily transported across the epithelium into the lumen. It may be attributed to the affinity of epithelial cells to the positive charge. Thus, the organoid can be utilized as an appropriate model to mimic the functions of the intestinal epithelium and can be used as a model to evaluate the benefits of nanoparticle-based drug delivery.     

茶谷蛾成虫触角转录组及嗅觉相关基因分析

为筛选茶谷蛾嗅觉相关基因,采用IlluminaHiSeq 4000高通量测序平台分别对茶谷蛾雌雄成虫触角进行转录组测序及生物信息学分析,共获得茶谷蛾触角转录组37 708条unigenes。通过同源性比对,在NR数据库成功注释16 027条unigenes;有11 701条unigenes得到GO注释,根据其功能可分为细胞组分、分子功能和生物过程三大类40亚类;有6 047个unigenes得到KOG注释,按照功能分为25类;根据KEGG数据库,有12 009条unigenes注释到283个通路。根据注释信息,挖掘到238个候选嗅觉相关基因,包括108个气味结合蛋白基因,55个气味/嗅觉受体基因,26个味觉受体基因、25个离子型受体基因、11个化学感受蛋白基因、4个感觉神经元膜蛋白基因、4个感官知觉基因、4个化学感受受体基因和1个气味降解酶基因。通过基因差异表达分析,筛选出12个气味结合蛋白基因、9个气味/嗅觉受体基因、4个信息素结合蛋白、3个味觉受体基因、1个化学感受蛋白基因和1个离子型受体蛋白基因。本研究获得了茶谷蛾触角转录组数据,并鉴定出候选嗅觉相关基因,为进一步研究茶谷蛾的基因功能及嗅觉感受机制奠定分子基础。     

昆虫嗅觉相关蛋白的研究进展

昆虫对自然环境中复杂化学信号的识别多依赖于其灵敏的嗅觉系统,选择寄主、觅食、寻找配偶等行为的发生都以嗅觉识别为基础,而完成嗅觉识别还需要多种嗅觉相关蛋白的参与。嗅觉相关蛋白主要包括6种,即气味结合蛋白、化学感受蛋白、气味受体、感觉神经元膜蛋白、离子型受体和气味降解酶。不同种类和性别的昆虫中,嗅觉蛋白的种类、数量和分布各不相同。由于嗅觉蛋白在昆虫识别外界气味分子中的重要作用,国内外近年来对其展开了广泛、深入的研究。本文从几种嗅觉相关蛋白的生化特性、分子结构、生理功能、分布表达部位和研究概况等角度,较详细地综述了近年来国内外昆虫嗅觉相关蛋白的研究进展。     

Baked product texture: Correlations between instrumental and sensory characterization using Flash Profile

Fifteen wheat doughs with various compositions have been selected and baked in order to obtain products with densities in the range of commercial bread values (0.25–0.35 g/cm³). A quick sensory profiling technique (Flash Profile), based on the combination of free choice profiling and a comparative evaluation of the whole product set was used. The sensory jury had to focus on the sensory perception of crumb texture (tactile and visual). The treatment of collected data by Generalized Procustes Analysis shows that products were perceived differently by the panel. The main differences concern the uniformity and the size of gas cells but also mechanical properties of corresponding crumb for which attributes like hardness, springiness and crumbliness were used. Instrumental characterization was performed using uniaxial compression (Young's modulus) and image analysis based on texture granulometry (fineness and homogeneity of cell distribution). A Multiple Factor Analysis allowed assessing the correlations between the sensory attributes and the instrumental measurements. Density and Young's modulus are positively correlated with the sensory elasticity. The instrumental and sensory measurements of the size and of the homogeneity of the cells distribution are correlated.     

Nitric Oxide Synthase in the Central Nervous System and Peripheral Organs of Stramonita haemastoma: Protein Distribution and Gene Expression in Response to Thermal Stress

Nitric oxide (NO) is generated via the oxidation of l-arginine by the enzyme NO synthase (NOS) both in vertebrates and invertebrates. Three NOS isoforms, nNOS, iNOS and eNOS, are known in vertebrates, whereas a single NOS isoform is usually expressed in invertebrates, sharing structural and functional characteristics with nNOS or iNOS depending on the species. The present paper is focused on the constitutive Ca²⁺/calmodulin-dependent nNOS recently sequenced by our group in the neogastropod Stramonita haemastoma (ShNOS). In this paper we provide new data on cellular distribution of ShNOS in the CNS (pedal ganglion) and peripheral organs (osphradium, tentacle, eye and foot) obtained by WB, IF, CM and NADPHd. Results demonstrated that NOS-like proteins are widely expressed in sensory receptor elements, neurons and epithelial cells. The detailed study of NOS distribution in peripheral and central neurons suggested that NOS is both intracellular and presynaptically located. Present findings confirm that NO may have a key role in the central neuronal circuits of gastropods and in sensory perception. The physiological relevance of NOS enzymes in the same organs was suggested by thermal stress experiments demonstrating that the constitutive expression of ShNOS is modulated in a time- and organ-dependent manner in response to environmental stressors.     

Caged Dexamethasone/Quercetin Nanoparticles,Formed of the Morphogenetic Active Inorganic Polyphosphate,are Strong Inducers of MUC5AC

Inorganic polyphosphate (polyP) is a widely distributed polymer found from bacteria to animals, including marine species. This polymer exhibits morphogenetic as well as antiviral activity and releases metabolic energy after enzymatic hydrolysis also in human cells. In the pathogenesis of the coronavirus disease 2019 (COVID-19), the platelets are at the frontline of this syndrome. Platelets release a set of molecules, among them polyP. In addition, the production of airway mucus, the first line of body defense, is impaired in those patients. Therefore, in this study, amorphous nanoparticles of the magnesium salt of polyP (Mg-polyP-NP), matching the size of the coronavirus SARS-CoV-2, were prepared and loaded with the secondary plant metabolite quercetin or with dexamethasone to study their effects on the respiratory epithelium using human alveolar basal epithelial A549 cells as a model. The results revealed that both compounds embedded into the polyP nanoparticles significantly increased the steady-state-expression of the MUC5AC gene. This mucin species is the major mucus glycoprotein present in the secreted gel-forming mucus. The level of gene expression caused by quercetin or with dexamethasone, if caged into polyP NP, is significantly higher compared to the individual drugs alone. Both quercetin and dexamethasone did not impair the growth-supporting effect of polyP on A549 cells even at concentrations of quercetin which are cytotoxic for the cells. A possible mechanism of the effects of the two drugs together with polyP on mucin expression is proposed based on the scavenging of free oxygen species and the generation of ADP/ATP from the polyP, which is needed for the organization of the protective mucin-based mucus layer.     

萌发大豆种子中子叶细胞内质体发育与解体的变化

本文分别报道了大豆（ＧｌｙｃｉｎｅｍａｘＬ．）种子在光下和在暗处萌发过程中子对细胞内质体的发育及解体过程。电镜观察的结果表明，大豆种子在吸水膨胀期间，子叶细胞内只有较少的、近球形的（数量为１一３个、直径为３一４微米）原质体，其内有２—６个淀粉粒。随着吸水膨胀时间的加长，子叶细胞内质体数量、体积、淀粉粒都有所增加（数量为５—１０个、直径为５—６微来、淀粉粒为８－１２个）。播种后在光下发育４—８天期间，子叶细胞原质体内出现５—１０个散在于基质中的片层结构；播种１２天时，１０—２０个片层结构垛叠在一起构成基粒，其数量为２—８个。此时原质体发育成为叶绿体。１３－１９天后，子叶日起黄化枯萎，叶绿体内片层结构多处膨胀，被膜解体，基质中出现５—１０个脂质球。大豆种子在暗处发育时，子叶细胞的原质体内首先形成伸展的、数量为１５—２０个片层结构。随着发育，片尽结构增多，这些片层结构并合形成原片层体，以后逐渐收缩成紧密的晶格。随着子叶的衰败，原片层体解体。     

Differential cytotoxicity of the isolated protein fraction of Escumite bean (Phaseolus acutifolius)

The Escumite bean (Phaseolus acutifolius) is an edible legume which in raw form is highly toxic to rats. Proteins were separated by DEAE cellulose and affinity chromatography. Hemagglutinating activity, trypsin inhibitory effect, cytotoxicity on human peripheral lymphocytes and on intestinal epithelial cells of rats, and mitogenic activity were assayed with each protein fraction. Hemagglutinins and trypsin inhibitory fractions showed differential toxicity with lymphocytes as compared to intestinal epithelial cells. A protein fraction without the previous activities was cytotoxic mainly to intestinal epithelial cells.     

Domoic Acid Epileptic Disease

Domoic acid epileptic disease is characterized by spontaneous recurrent seizures weeks to months after domoic acid exposure. The potential for this disease was first recognized in a human case study of temporal lobe epilepsy after the 1987 amnesic shellfish-poisoning event in Quebec, and was characterized as a chronic epileptic syndrome in California sea lions through investigation of a series of domoic acid poisoning cases between 1998 and 2006. The sea lion study provided a breadth of insight into clinical presentations, unusual behaviors, brain pathology, and epidemiology. A rat model that replicates key observations of the chronic epileptic syndrome in sea lions has been applied to identify the progression of the epileptic disease state, its relationship to behavioral manifestations, and to define the neural systems involved in these behavioral disorders. Here, we present the concept of domoic acid epileptic disease as a delayed manifestation of domoic acid poisoning and review the state of knowledge for this disease state in affected humans and sea lions. We discuss causative mechanisms and neural underpinnings of disease maturation revealed by the rat model to present the concept for olfactory origin of an epileptic disease; triggered in dendodendritic synapases of the olfactory bulb and maturing in the olfactory cortex. We conclude with updated information on populations at risk, medical diagnosis, treatment, and prognosis.     

Pacific-Ciguatoxin-2 and Brevetoxin-1 Induce the Sensitization of Sensory Receptors Mediating Pain and Pruritus in Sensory Neurons

Ciguatera fish poisoning (CFP) and neurotoxic shellfish poisoning syndromes are induced by the consumption of seafood contaminated by ciguatoxins and brevetoxins. Both toxins cause sensory symptoms such as paresthesia, cold dysesthesia and painful disorders. An intense pruritus, which may become chronic, occurs also in CFP. No curative treatment is available and the pathophysiology is not fully elucidated. Here we conducted single-cell calcium video-imaging experiments in sensory neurons from newborn rats to study in vitro the ability of Pacific-ciguatoxin-2 (P-CTX-2) and brevetoxin-1 (PbTx-1) to sensitize receptors and ion channels, (i.e., to increase the percentage of responding cells and/or the response amplitude to their pharmacological agonists). In addition, we studied the neurotrophin release in sensory neurons co-cultured with keratinocytes after exposure to P-CTX-2. Our results show that P-CTX-2 induced the sensitization of TRPA1, TRPV4, PAR2, MrgprC, MrgprA and TTX-r NaV channels in sensory neurons. P-CTX-2 increased the release of nerve growth factor and brain-derived neurotrophic factor in the co-culture supernatant, suggesting that those neurotrophins could contribute to the sensitization of the aforementioned receptors and channels. Our results suggest the potential role of sensitization of sensory receptors/ion channels in the induction or persistence of sensory disturbances in CFP syndrome.     

Effect of matrigel on function and morphology of human endometrial epithelial cell in vitro

INTRODUCTION: The importance of extra cellular matrix (ECM) in development and function of different cells has been reported but little is known about its role in human endometrial epithelial cells. The aim of the present study was to examine effects of artificial ECM (Matrigel) and progesterone on the function and morphology of human endometrial epithelial cells in vitro. METHODS: Endometrial samples were removed, with informed patients consent and Ethics Committee approval, from 17 previously fertile women undergoing total abdominal hysterectomy. The tissue was dissociated and centrifuged to provide an epithelial rich suspension which was cultured either on plastic or seeded into Matrigel to produce polarized cells and then supplemented with or without progesterone (10(-6) M). The amount of nucleic acid content of the cells in both in vitro model systems was examined by DNA, RNA extraction methods. The DNA and RNA content were later measured by spectrophotometry. RESULTS: The amount of total RNA in cells grown on Matrigel (23 +/- 1.5 pg/cell) was more than double that in cells grown on pllastic (9.1 +/- 1.4 pg/cell). Cells cultured on both in vitro model systems had RNA induced by steroid hormones, but the extent of induction was greater in cells grown on Matrigel (30 +/- 2 pg/cell) than those on plastic (12 +/- 1.9 pg/cell). Cells cultured on Matrigel were differentiated and became polarized but cells grown on plastic proliferated to full confluency. Cells grown on Matrigel with progesterone supplementation were highly polarized, euchromatic and had greater mitochondria and accumulation of glycogen, when compared to unsupplemented cultures. CONCLUSION: These results suggest that ECM plays an important role in gene expression, polarization and differentiation of human endometrial epithelial cells in vitro. Endometrial cells grown on ECM responded to steroid hormone in a manner to that reported in endometrial cells in vivo.     

2个小蘑菇属中国新记录种

对采自广东省的2份小磨菇属Micropsalliota标本进行鉴定,采用形态鉴定和ITS序列比对相结合的方法,最终将这2份标本鉴定为二瓣小蘑菇(Micropsalliota bifida R.L.Zhao,Desjardin,Soytong&K.D.Hyde)和亚白小蘑菇(Micropsalliota subalba ...     

大豆子叶发育过程中,子叶细胞内造粉质体分化和脱分化过程的电镜观察

大豆开花后18～43天,子叶细胞含叶绿素。细胞内原质林可逐渐积累淀粉粒;基质内有基粒和基质片层。原质体发育为造粉质体。这种造粉质体属“绿色造粉质体”。开花后53～63天,造粉质体内淀粉粒数目减少,体积缩小;片层结构肿胀,并逐渐解体。造粉质体脱分化为原质体。造粉质体的分化和脱分化过程与蛋白质和脂类的积累密切相关。     

A study on the effect of thiotepa on mice spermatogenesis using light and electronic microscope

The present study was designed to explore the spermatogenic effect of intraperitoneal administration of thiotepa in mice. It is known the chemotherapy could affect testicular function and result in infertility. There are few reports on the side effect of thiotepa on spermatogenesis when are used as anticancer drug. Therefore, in the present study the effect of thiotepa on spermatogenesis was evaluated by electron microscopy. A total of 20 balb/c mice were used in this study. They were divided into control and thiotepa treated groups. Thiotepa was administrated as 2.5 mg kg(-1) for 5 days. The mice were sacrificed after 5 weeks and testicular specimens were removed, fixed in boueins fixative and 2.5% Glutaraldehide then prepared for light and electron microscopic study. Light microscopy showed that the thickness of germinal epithelium was decreased in thiotepa treated group and many seminiferous tubules have lost germinal cells. Electron microscopy revealed that in experimental group several intercellular spaces appeared between spermatogonial and sertoli cells. The basement membrane became irregular and intercellular vacuoles were present in sertoli and spermatogonial cells. Nuclear chromatin was condensed and there were several vacuolated mitochondria. It was indicated that thiotepa affected testicular germinal epithelium by both cytotoxic effect and induction of apoptosis.