南京紫金山植食性蝽类发生特点

在以中山植物园为主的南京紫金山范围内,通过野外调查等方法,共发现常见植食性蝽类37种,隶属10科,并记录了寄主植物的种类。重点描述了其中主要9种的发生规律以及对黑莓、蓝浆果等的为害,可为农林植物的蝽类虫害治理提供参考。     

A New Pentachrome Method for the Simultaneous Staining of Collagen and Sulfated Mucopolysaccharides

Collagen is one of the most common fibers in the extracellular matrix, where sulfated mucopolysaccharides are also located. In addition, sulfated mucopolysaccharides are present in some globet cells and secretory glands. The objective of this article is to develop a new staining method that detects these two macromolecules simultaneously in the same sample. The method described stains tissues in five fundamental colors: collagen in red; sulfated mucopolysaccharides in violet; red blood cells in yellow; muscle in orange; and nuclei in green.As a conclusion, it will be interesting in the future to evaluate whether this method could be used as a basic histological method, as a histology teaching tool, or even in histopathological and cytopathological studies.     

Experimentally increased reproductive effort alters telomere length in the blue tit (Cyanistes caeruleus)

Telomeres have recently been suggested to play important role in ageing and are considered to be a reliable ageing biomarkers. The life history theory predicts that costs of reproduction should be expressed in terms of accelerated senescence, and some empirical studies do confirm such presumption. Thus, a link between reproductive effort and telomere dynamics should be anticipated. Recent studies have indeed demonstrated that reproduction may trigger telomere loss, but actual impact of reproductive effort has not received adequate attention in experimental studies. Here, we experimentally manipulated reproductive effort by increasing the brood size in the wild blue tit (Cyanistes caeruleus). We show that parents attending enlarged broods experienced larger yearly telomere decay in comparison to control birds attending unaltered broods. In addition, we demonstrate that the change in telomere length differs between sexes, but this effect was independent from our treatment. To our knowledge, this is the first experimental study in the wild revealing that telomere dynamics may be linked to reproductive effort. Thus, telomere shortening may constitute one of the potential proximate mechanisms mediating the costs of reproduction.     

Crystal structure of NTPDase2 in complex with the sulfoanthraquinone inhibitor PSB-071

In many vertebrate tissues CD39-like ecto-nucleoside triphosphate diphosphohydrolases (NTPDases) act in concert with ecto-5′-nucleotidase (e5NT, CD73) to convert extracellular ATP to adenosine. Extracellular ATP is a cytotoxic, pro-inflammatory signalling molecule whereas its product adenosine constitutes a universal and potent immune suppressor. Interference with these ectonucleotidases by use of small molecule inhibitors or inhibitory antibodies appears to be an effective strategy to enhance anti-tumour immunity and suppress neoangiogenesis. Here we present the first crystal structures of an NTPDase catalytic ectodomain in complex with the Reactive Blue 2 (RB2)-derived inhibitor PSB-071. In both of the two crystal forms presented the inhibitor binds as a sandwich of two molecules at the nucleoside binding site. One of the molecules is well defined in its orientation. Specific hydrogen bonds are formed between the sulfonyl group and the nucleoside binding loop. The methylphenyl side chain functionality that improved NTPDase2-specificity is sandwiched between R245 and R394, the latter of which is exclusively found in NTPDase2. The second molecule exhibits great in-plane rotational freedom and could not be modelled in a specific orientation. In addition to this structural insight into NTPDase inhibition, the observation of the putative membrane interaction loop (MIL) in two different conformations related by a 10° rotation identifies the MIL as a dynamic section of NTPDases that is potentially involved in regulation of catalysis.     

光敏剂甲苯胺蓝在口腔颊粘膜渗透性的研究

目的:研究不同时间,甲苯胺蓝(Toluidine Blue O,TBO)在大鼠炎症性口腔颊粘膜渗透的浓度变化,及甲苯胺蓝与炎症细胞分布之间的关系。方法:实验选取wistar大鼠32只,炎症组大鼠20只,建立以金葡菌为优势菌的感染炎症创口模型。将浓度为1mg/mL甲苯胺蓝溶液置于大鼠感染炎症创口组织上5、10分钟后处死,正常粘膜组大鼠8只,于甲苯胺蓝在正常颊粘膜渗透5、10、20、40分钟后处死,避光条件下取组织块进行冰冻切片,即刻荧光显微镜下观察荧光分布;冰冻切片进行HE染色,观察炎症细胞分布。采用Image Pro-plus 6.0软件检测荧光分布的光密度、分布面积以及炎症分布面积。结果:1创口周围正常粘膜及正常完整粘膜组的甲苯胺蓝均停留在角化层,未穿透上皮层,和时间无相关关系;2炎症5分钟组平均荧光分布可达到炎症细胞分布面积的89%,炎症10分钟组可达108%;炎症组在创口表面及深部,荧光光密度均无显著差异。结论:1甲苯胺蓝可有效分布于感染的炎症组织,但不能穿透正常组织,完整上皮可保护正常组织免受光动力的杀伤。2浓度为1 mg/mL的甲苯胺蓝溶液渗透时间为10分钟时,创口中甲苯胺蓝的分布与炎症细胞的分布基本一致,甲苯胺蓝浓度梯度无显著变化。提示甲苯胺蓝作为光敏剂在针对口腔创口感染的抗菌光动力疗法中可有效、安全的发挥作用。     

Spectroscopic and photochemical analysis of proteorhodopsin variants from the surface of the Arctic Ocean

Proteorhodopsin (PR), a retinal-containing seven transmembrane helix protein, functions as a light-driven proton pump. Using PCR, we isolated 18 PR variants originating from the surface of the Arctic Ocean. Their absorption maxima were between 517 and 546 nm at pH 7. One of the isolates turned out to be identical to GPR (green light-absorbing proteorhodopsin) from Monterey Bay. Interestingly, 10 isolates had replaced a tyrosine in the retinal-binding site (Tyr200 in GPR) with Asn. They showed a slower photocycle, more blue-shifted absorption maxima at pH 10, and relatively larger DeltaH and DeltaS of activation of the transition between the O intermediate and the ground state compared to GPR.     

CHARACTERIZATION OF A DINOFLAGELLATE CRYPTOCHROME BLUE‐LIGHT RECEPTOR WITH A POSSIBLE ROLE IN CIRCADIAN CONTROL OF THE CELL CYCLE1

Karenia brevis (C. C. Davis) G. Hansen et Moestrup is a dinoflagellate responsible for red tides in the Gulf of Mexico. The signaling pathways regulating its cell cycle are of interest because they are the key to the formation of toxic blooms that cause mass marine animal die‐offs and human illness. Karenia brevis displays phased cell division, in which cells enter S phase at precise times relative to the onset of light. Here, we demonstrate that a circadian rhythm underlies this behavior and that light quality affects the rate of cell‐cycle progression: in blue light, K. brevis entered the S phase early relative to its behavior in white light of similar intensity, whereas in red light, K. brevis was not affected. A data base of 25,000 K. brevis expressed sequence tags (ESTs) revealed several sequences with similarity to cryptochrome blue‐light receptors, but none related to known red‐light receptors. We characterized the K. brevis cryptochrome (Kb CRY) and modeled its three‐dimensional protein structure. Phylogenetic analysis of the photolyase/CRY gene family showed that Kb CRY is a member of the cryptochrome DASH (CRY DASH) clade. Western blotting with an antibody designed to bind a conserved peptide within Kb CRY identified a single band at ～55 kDa. Immunolocalization showed that Kb CRY, like CRY DASH in Arabidopsis, is localized to the chloroplast. This is the first blue‐light receptor to be characterized in a dinoflagellate. As the Kb CRY appears to be the only blue‐light receptor expressed, it is a likely candidate for circadian entrainment of the cell cycle.     

Responses of strawberry plantlets cultured in vitro under superbright red and blue light-emitting diodes (LEDs)

Unrooted strawberry cv. `Akihime' shoots with three leaves obtained from standard mixotrophic cultures were cultured in the ``Culture Pack'-rockwool system with sugar-free MS medium under CO<sub>2</sub>-enriched condition. To examine the effect of superbright red and blue light-emitting diodes (LEDs) on in vitro growth of plantlets, these cultures were placed in an incubator, ``LED PACK', with either red LEDs, red LEDs1blue LEDs or blue LEDs light source. To clarify the optimum blue and red LED ratio, cultures were placed in ``LED PACK 3' under LED light source with either 100, 90, 80, or 70% red + 0, 10, 20, 30% blue, respectively, and also under standard heterotrophic conditions. To determine the effects of irradiation level, cultures were grown under 90% red LEDs + 10% blue LEDs at 45, 60 or 75 mol m^–2 s^–1 . Plantlet growth was best at 70% red + 30% blue LEDs. The optimal light intensity was 60 mol m^–2 s^–1. Growth after transfer to soil was also best after in vitro culture with plantlets produced were 70% red LEDs + 30% blue LEDs.     

Ionic imbalance and lack of effect of adjuvant treatment with methylene blue in the hamster model of leptospirosis

Leptospirosis in humans usually involves hypokalaemia andhypomagnesaemia and the putative mechanism underlying such ionic imbalances maybe related to nitric oxide (NO) production. We previously demonstrated thecorrelation between serum levels of NO and the severity of renal disease inpatients with severe leptospirosis. Methylene blue inhibits soluble guanylylcyclase (downstream of the action of any NO synthase isoforms) and was recentlyreported to have beneficial effects on clinical and experimental sepsis. Weinvestigated the occurrence of serum ionic changes in experimental leptospirosisat various time points (4, 8, 16 and 28 days) in a hamster model. We alsodetermined the effect of methylene blue treatment when administered as anadjuvant therapy, combined with late initiation of standard antibiotic(ampicillin) treatment. Hypokalaemia was not reproduced in this model: all ofthe groups developed increased levels of serum potassium (K). Furthermore,hypermagnesaemia, rather than magnesium (Mg) depletion, was observed in thishamster model of acute infection. These findings may be associated with anaccelerated progression to acute renal failure. Adjuvant treatment withmethylene blue had no effect on survival or serum Mg and K levels duringacute-phase leptospirosis in hamsters.