Tabanidae (Diptera) of Saudi Arabia

Samples were collected from southern, central and eastern regions of Saudi Arabia using Malaise traps and sweep nets. Nine species of Tabanidae were identified, two for the first time from Saudi Arabia, Hybomitra peculiaris (Szilády) and Atylotus pulchellus (Loew).Therefore, the total number of Tabanidae in Saudi Arabia is 31 species. Remarks of the species recorded in this study were given. A key to the genera of Tabanidae occurring in the Arabian Peninsula is also provided. Available literature for Saudi Arabian Tabanidae is summarized and provided. It is concluded that the tabanid fauna of Saudi Arabia is more similar to that of the Palaearctic region than to the Afrotropical region.     

IN VIVO MEASUREMENT OF ACTIVE OXYGEN PRODUCTION IN THE BROWN ALGA FUCUS EVANESCENS USING 2′,7′-DICHLOROHYDROFLUORESCEIN DIACETATE1

Intracellular production of active oxygen in the brown alga Fucus evanescens C. Ag. was studied by measuring the capacity for in vivo conversion of 2′,7′-dichlorohydrofluorescein diacetate (DCFH-DA) to the fluorescent dye 2′,7′-dichlorofluorescein (DCF), both in emersed and immersed seaweeds. Algae were incubated in seawater containing DCFH-DA under a range of conditions, and it was also possible to load algae with DCFH-DA and then follow subsequent DCF production in emersed tissue. DCF formation was linear for at least 2 h in both darkness and light, with the rate of formation increasing with the light level. DCF formation was temperature dependent. It also increased when algae were treated with H₂O₂ or methyl viologen (paraquat), which disrupts photosystem 1 electron transport and increases O^?₂ production. Exogenous catalase reduced in vivo DCF production, presumably by lowering cellular concentrations of H₂O₂. Hydrogen peroxide was released into the seawater by illuminated algae resulting in external dye conversion to DCF. However, this does not interfere with in vivo measurement of DCF by loaded, washed algae because DCF leakage appeared to be negligible. Internal DCF did not affect photosynthetic oxygen production relative to untreated controls. Overall, our data suggest that DCFH-DA is a potentially very useful probe for studying active oxygen metabolism in seaweeds subjected to environmental stresses.     

Ultrastructure of the Trichomonad Flagellate Stephanonympha nelumbium

ABSTRACT Stephanonympha nelumbium is a large trichomonad measuring 45–60 μm in length and 20–40 μm in width. It is a member of the multinucleate and multiflagellate family Calonymphidae. While the numerous flagella arise in groups of four at the anterior cell pole, the posterior body portion is covered with attached spirochetes and rod-like bacteria. Generally, in the apical body portion of S. nelumbium , 50–100 nuclei are arranged in five to seven circular rows. Each nucleus is associated with a typical mastigont system, comprised of three anterior flagella, one recurrent flagellum being attached to the cell surface for a certain distance, and several typical root structures. Akaryomastigonts and costas do not occur. The fine structure of S. nelumbium corresponds with that of other calonymphids. The main difference to Calonympha is that the axostyle does not embrace the nucleus but passes it in form of a flattened rod.     

Effects of Visible and Ultraviolet Light on Carotene-deficient Mutants of Crypthecodinium cohnii

Synopsis.
The ability of carotenoids to protect a heterotrophic dinoflagellate, Crypthecodinium cohnii , from photodynamic damage by sunlight in the presence of an exogenous dye was demonstrated. Wild-type C. cohnii and 2 carotcnoid-deficient mutants were plated on agar-solidified media and exposed to natural sunlight. The wild-type strain, which synthesizes γ–carotene and β–carotene, had the lowest mortality. Mutant car 17 which accumulates mainly §–carotene had an intermediate mortality rate while the albino mutant, car 3, which contains only phytoene, lost viability most rapidly. Wild-type cells treated with diphenylaminc, a carotenogenic inhibitor, were killed at the same rate as mutant car 3. The survival rate of mutants on exposure to sunlight was dependent upon the chromophore length of the accumulated carotenoids. The 3 strains showed no difference in rate of mortality when exposed to ultraviolet light. Protection from sunlight by accumulation of carotenes may be an important ecological factor for this species whose natural habitat is tidepools.     

利用表型数据构建陆地棉核心种质

以5963份陆地棉种质资源为材料,根据品种主要突变性状和品种类型分组成11组群,在分组的基础上利用21个表型性状,用非加权类平均聚类分析法,构建了281份陆地棉核心种质,占全部种质资源总量的4.71%。利用不同性状的均值t测验、方差F测验、变异系数、多样性指数t检验、均值、极差、表型方差、变异系数、均值差异百分率、方差差异百分率、极差符合率、变异系数变化率、主成分分析等参数进行核心种质代表性检验和评价。结果表明,所构建的陆地棉核心种质可以代表全部种质的遗传多样性。     

Melatonin administration prevents lipopolysaccharide-induced oxidative damage in phenobarbital-treated animals

The protective effect of melatonin on lipopolysaccharide (LPS)-induced oxidative damage in phenobarbital-treated rats was measured using the following parameters: changes in total glutathione (tGSH) concentration, levels of oxidized glutathione (GSSG), the activity of the antioxidant enzyme glutathione peroxidase (GSH-PX) in both brain and liver, and the content of cytochrome P450 reductase in liver. Melatonin was injected intraperitoneally (ip, 4mg/kg BW) every hour for 4 h after LPS administration; control animals received 4 injections of diluent. LPS was given (ip, 4 mg/kg) 6 h before the animals were killed. Prior to the LPS injection, animals were pretreated with phenobarbital (PB), a stimulator of cytochrome P450 reductase, at a dose 80 mg/kg BW ip for 3 consecutive days. One group of animals received LPS together with N^w-nitro-L-arginine methyl ester (L-NAME), a blocker of nitric oxide synthase (NOS) (for 4 days given in drinking water at a concentration of 50 mM). In liver, PB, in all groups, increased significantly both the concentration of tGSH and the activity of GSH-PX. When the animals were injected with LPS the levels of tGSH and GSSG were significantly higher compared with other groups while melatonin and L-NAME significantly enhanced tGSH when compared with that in the LPS-treated rats. Melatonin alone reduced GSSG levels and enhanced the activity of GSH-PX in LPS-treated animals. Additionally, LPS diminished the content of cytochrome P450 reductase with this effect being largely prevented by L-NAME administration. Melatonin did not change the content of P450 either in PB- or LPS-treated animals. In brain, melatonin and L-NAME increased both tGSH levels and the activity of GSH-PX in LPS-treated animals. The results suggest that melatonin protects against LPS-induced oxidative toxicity in PB-treated animals in both liver and brain, and the findings are consistent with previously published observations related to the antioxidant activity of the pineal hormone.     

在墨尔本召开的第18届国际植物学大会做出的有关名称发表要求的变化——电子出版物对你意味着什么？

《国际植物命名法规》的修订由每六年一次的国际植物学大会（IBC）命名分会来决定。第18届国际植物学大会在澳大利亚墨尔本举行;命名分会于2011年7月18日至22日召开,其决议获得7月30日的全体会议通过。“墨尔本法规”有几个重要的变化,将影响新名称的发表。这些变化中的两个将在“墨尔本法规”出版前的几个月,即于2012年1月1日起生效。通过以移动文档格式（Portable Document Format;pdf）在线发表的具有国际标准连续出版物号（ISSN）或国际标准图书编号（ISBN）的电子出版物,将构成有效发表。新分类群名称的合格发表所必须的拉丁文描述或特征集要将更改为拉丁文或英文描述或特征集要。此外,自2013年1月1日起,被处理为真菌的生物的新名称必须在原始资料（某一名称合格发表时与之有关的所有资料）中引证一个由一家公认的存储库（例如MycoBank）签发的标识码,才构成合格发表。本文提供了有关电子出版物的新规则的草案文本,并概述了相应的最佳做法。     

Short-Term Responders of Non–Small Cell Lung Cancer Patients to EGFR Tyrosine Kinase Inhibitors Display High Prevalence of TP53 Mutations and Primary Resistance Mechanisms

Non–small cell lung cancer (NSCLC) with activating EGFR mutations in exon 19 and 21 typically responds to EGFR tyrosine kinase inhibitors (TKI); however, for some patients, responses last only a few months. The underlying mechanisms of such short responses have not been fully elucidated. Here, we sequenced the genomes of 16 short-term responders (SR) that had progression-free survival (PFS) of less than 6 months on the first-generation EGFR TKI and compared them to 12 long-term responders (LR) that had more than 24 months of PFS. All patients were diagnosed with advanced lung adenocarcinoma and harbored EGFR 19del or L858R mutations before treatment. Paired tumor samples collected before treatment and after relapse (or at the last follow-up) were subjected to targeted next-generation sequencing of 416 cancer-related genes. SR patients were significantly younger than LR patients (P < .001). Collectively, 88% of SR patients had TP53 variations compared to 13% of LR patients (P < .001). Additionally, 37.5% of SR patients carried EGFR amplifications compared to 8% of LR patients. Other potential primary resistance factors were also identified in the pretreatment samples of 12 SR patients (75%), including PTEN loss; BIM deletion polymorphism; and amplifications of EGFR, ERBB2, MET, HRAS, and AKT2. Comparatively, only three LR patients (25%) were detected with EGFR or AKT1 amplifications that could possibly exert resistance. The diverse preexisting resistance mechanisms in SR patients revealed the complexity of defining treatment strategies even for EGFR-sensitive mutations.     

荷花品种分类新系统

就古今中外荷花工作者对茶花品种分类研究进行的分析比较,提出品种分类的基本原则,对《中国荷花品种图志》（１９８９）制定的荷品种分类系统作了若干调整,即认定美国莲（Ｎｅｌｕｍｂｏｌｕｔｅａ）为中国莲亚种后重新确定基分类地位;将中,小株型品种并列与大标型品种分开;增设新类型,补充重台型品种和间色花品种,调整后制定的荷花品种分类新系统检索表,包括３种系,６群,１４类,３８型,含２７８个品种。