Sequence analysis of mouse cDNAs encoding ribosomal proteins L12 and L18

Mouse cDNAs encoding ribosomal proteins (r-proteins), L12 and L18, were isolated and their sequences determined. The L12 cDNA was found to contain 639 bp, including a coding sequence of 498 nucleotides (nt), 5' (78 nt) and 3' (45 nt) untranslated regions (UTRs), and a poly(A) tail of 18 nt. The L18 cDNA was shown to consist of 648 bp, including a coding sequence of 567 nt, 5' (26 nt) and 3' (39 nt) UTRs, and a poly(A) tail of 16 nt. The nt sequences of the protein-coding region from the mouse L12 and L18 cDNAs were found to exhibit 96% and 92% identity, respectively, with those of the rat. With the use of mouse L12 and L18 cDNA probes, multiple (at least 10) copies of the L12 and L18 gene families were shown to be present in the mouse and rat genomes. However, there was no sequence heterogeneity detected among seven L18 cDNA clones, indicating that only one copy of the L18 gene-related sequences is functional, and the other copies are presumably nonfunctional pseudogenes. The complete amino acid (aa) sequences of the mouse r-proteins, L12 and L18, were deduced from the nt sequences of their cDNA clones. L12 has 165 aa and a M_r, of 17 790, while L18 has 188 aa and a M_r of 21 570. The aa sequences of the mouse r-proteins, L12 and L18, exhibit 98% and 94% identity, respectively, to those of rat.     

Effects of Leontice smirnowii tuber monodesmosides and crude extract in carrageenan- and histamine-induced acute inflammation model of rats

Leontice smirnowii is a member of the Berberidaceae family. We have recently reported the 1,1-diphenyl-2-picryl-hydrazyl radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, reducing power and metal chelating activities of L. smirnowii products. In the current study we investigated the possible effects of the crude extracts of L. smirnowii (CELS) and the monodesmoside's purified extract (MPE) of L. smirnowii in the carrageenan- and histamine-induced acute inflammation models in rats. The experiment revealed that CELS and MPE have anti-inflammatory effects, dose dependently in carrageenan-induced acute inflammation. On the other hand, their proinflammatory effects were surprisingly observed, especially in low doses, in the histamine-induced acute inflammation model. Summarizing these data, we may state that CELS and MPE exert their anti-inflammatory effects via non-histaminergic pathways.     

浅裂剪秋萝和丝瓣剪秋萝传粉特性的初步研究

为了探究浅裂剪秋萝(Lychnis cognata)和丝瓣剪秋萝(L. wilfordii)的传粉生物学特征, 从花部特征、花粉呈现规律及传粉者访花行为等方面对其开展研究。结果表明, 2种剪秋萝的花期持续时间相近, 但浅裂剪秋萝始花日期较早; 二者花部特征虽有显著差异, 但主要传粉者均为碧翠凤蝶(Papilio bianor)。在开花过程中, 2种剪秋萝的雄蕊均分2批呈现花粉, 第1批雄蕊的花粉生活力在开花后第1天达到最大值, 而第2批雄蕊在第2天达到最大值。浅裂剪秋萝的柱头可授性在开花后第5天最强, 而丝瓣剪秋萝在开花后第4天最强, 花粉生活力和柱头活性的时间差异表明两物种均为雌雄异熟。两物种共同的传粉者碧翠凤蝶对浅裂剪秋萝的访花高峰出现在上午8:00-11:00, 而对丝瓣剪秋萝的访花高峰出现在上午11:00-12:00, 导致访花高峰出现差异的主要影响因素可能是生境和花药开裂时间。     

长白落叶松过氧化氢酶LoCAT1基因克隆及表达分析

为了解长白落叶松过氧化氢酶(CAT)基因的相关信息,探究该基因在长白落叶松不同组织中及不同逆境胁迫下的表达特性,本研究根据长白落叶松转录组数据库中获得的CAT1基因全长序列设计引物,克隆得到长白落叶松CAT1基因,命名为LoCAT1。该基因完整的开放阅读框(ORF)长度为954bp,共编码317个氨基酸。系统进化树分析结果显示,LoCAT1基因与北美云杉、银杏等CAT基因亲缘关系较近。利用实时定量RT-PCR技术分析了LoCAT1基因在长白落叶松中的组织表达特异性和应对非生物胁迫的表达模式。结果表明:LoCAT1基因在长白落叶松的根、茎、叶中均有表达,其中在茎部表达量最低,在叶中相对表达量最高。在非生物胁迫下,LoCAT1基因在长白落叶松根、茎、叶中的表达均发生了变化,但表达模式不同。在NaCl处理后,根和茎中LoCAT1基因均表现为下调表达,在12h时表达量最低,而叶中LoCAT1基因表达在24h明显受抑制,随后被上调表达,胁迫96h时表达量最高。PEG6000处理后,根和茎中LoCAT1基因的表达在胁迫早期被明显抑制,随后被上调表达。而叶中LoCAT1基因的表达在所有时间点均表现为上调表达。本研究推测长白落叶松LoCAT1基因可能参与了植物响应逆境胁迫的应答。     

Evaluation of the efficacy of albendazole against the larvae of Taenia solium in experimentally infected pigs, and kinetics of the immune response

Cysticercosis, a disease of economic and public health importance, is caused by Cysticercus cellulosae, the metacestode stage of Taenia solium. Experimental induction of cysticercosis was achieved in young pigs by feeding an optimum dose of 20,000 T. solium (Indian strain) eggs after immunosuppression, to assess the effect of albendazole and development of the immune response to cysticercus antigens before and after treatment.

Histopathological studies revealed the presence of cysticerci in liver, lungs and muscles. Treatment with albendazole at 15 mg kg⁻¹ body weight daily for 30 days starting from day 0 or 15 days post-infection resulted in 100% cure rates. Increases in antibody titre to crude soluble extract and a Sephadex G-200 purified antigenic fraction of Cysticercus cellulosae were found on days 25, 40 and 55 post-infection in untreated pigs and those in which treatment started on day 15 post-infection, whereas no increase in antibody response was observed in pigs in which treatment started on day 0.     

Isolation of quinic acid derivatives and flavonoids from the aerial parts of Lactuca indica L. and their hepatoprotective activity in vitro

In our continuing study of biologically active compounds from Korean medicinal plants, we investigated the hepatoprotective constituents of the aerial parts of Lactuca indica L. (Compositae), since the methanolic extract of L. indica has hepatoprotective activity against hepatitis B virus (HBV) production. The bioactivity-guided separation of the methanolic extract of the aerial parts of L. indica resulted in the isolation of seven quinic acid derivatives (1, 3–4, 6, and 10–12), along with five flavonoids (2, 5, and 7–9). All the isolated compounds were evaluated for hepatoprotective activity by the HBV assay in vitro. In the human HBV-transfected liver cell line HepG2.2.15, all the compounds except 2 and 5 effectively reduced HBV DNA level in the release of mature HBV particles from HepG2.2.15 cultivation. Of the ten active compounds, treatment with 1, 3, and 12 led to significant reduction in the extracellular HBV DNA level, suggesting that they could be potent phytochemical agents against hepatitis B virus.     

Neutrophil myeloperoxidase deficiency associated with canine hepatozoonosis

Hepatozoonosis is a very important disease in dogs in Nigeria. Hepatozoonosis was reported in Nigeria in 18 dogs. The clinical signs included fever, anorexia, loss of weight, lameness, oculonasal discharge and conjunctivitis. Hematologic findings included leukocytosis due to neutrophilia and eosinophilia. Parasitemia varied from 1 to 9% of the circulating neutrophils in the peripheral blood smears of the dogs examined. Hepatozoon canis gametocytes were identified in circulating neutrophils of dogs. Peripheral blood smears from dogs confirmed to have natural H. canis infection were cytochemically stained for myeloperoxidase. Parasitized neutrophils were myeloperoxidase deficient while non-parasitized neutrophils were myeloperoxidase positive. This is considered important, because deficiency of the enzyme may be responsible for poor response of H. canis to chemotherapeutic agents.     

Synthesis and in vitro evaluation of leishmanicidal and trypanocidal activities of N-quinolin-8-yl-arylsulfonamides

In the present paper 12 N-quinolin-8-yl-arylsulfonamides synthesized by coupling 8-aminoquinolines with various arylsulfonylchlorides were assayed in vitro against Leishmania amazonensis, Leishmania chagasi and Trypanosoma cruzi strains. This series of new compounds were found to be selective for Leishmania spp. promastigote and amastigote forms. The most active compound was the N-(8-quinolyl)-3,5-difluoro-benzenesulfonamide 10 with an IC₅₀ against L. amazonensis and L. chagasi of 2.12 and 0.45 μM, respectively. The less cytotoxic biphenyl derivative 7 was very effective against intracellular L. amazonensis with a reduction of macrophage cell infection of 82.1% at 25 μM. In addition, a copper complex 17 of an inactive ligand was readily synthesized and showed high leishmanicidal and trypanocidal activity against both extra and intracellular forms.     

陕西子午岭北桑寄生的种群生命表与生存分析

陕西旬邑县子午岭的北桑寄生(Loranthus tanakae)寄生于子午岭优势种和建群种辽东栎(Quercus liaotungensis)上。该文通过调查子午岭北桑寄生的年龄结构, 编制了北桑寄生的静态生命表, 绘制了存活曲线、死亡率曲线、消失率曲线和生存函数曲线, 分析了种群的动态变化。结果表明: 子午岭北桑寄生种群存活曲线属于Deevey II型, 有较为稳定的死亡率, 消失率曲线和死亡率曲线变化趋势基本一致, 均有两个高峰, 一个出现在5龄, 另一个出现在10龄, 危险率曲线在6龄出现一个波动, 生存率曲线和累计死亡率曲线分别呈下降趋势和上升趋势, 均表现为前期高于后期, 北桑寄生在8龄后进入衰老期。由生存函数曲线年龄阶段看出, 子午岭北桑寄生种群具有前期、中期稳定, 后期衰退的特点。     

马铃薯甲虫气味结合蛋白的序列和基因表达谱分析

【目的】昆虫气味结合蛋白(OBPs)在昆虫嗅觉行为中发挥着重要作用。马铃薯甲虫Leptinotarsa decemlineata是马铃薯上一种最主要的毁灭性害虫。为阐明该虫嗅觉识别分子机制,本研究对马铃薯甲虫26个OBP基因序列特征及组织表达谱进行研究。【方法】基于马铃薯甲虫触角转录组测序数据,利用生物信息学方法及qRT-PCR技术,分别对马铃薯甲虫26个LdecOBPs (LdecOBP1-LdecOBP26)的系统进化及基因的组织表达谱进行分析。【结果】除LdecOBP26基因外,其余25个LdecOBPs基因序列均具有完整的开放阅读框,编码120~255个氨基酸残基,预测的蛋白分子量为13.66~29.38 kD,等电点为4.12~8.42,它们属于两个亚家族,其中13个为Classical-C OBPs, 12个为Minus-C OBPs。除LdecOBP3和LdecOBP26外,其他24个LdecOBPs的N端均由16~23个氨基酸组成的信号肽序列。不同的OBPs亚家族均具有各自典型保守的Cys残基。LdecOBPs之间高度分化,氨基酸序列一致性在3.20%~41.91%。系统进化树分析表明,LdecOBPs与沙葱萤叶甲Galeruca daurica的GdauOBPs亲缘关系最近。基因表达谱分析显示,26个LdecOBPs基因在马铃薯甲虫的不同组织中表达,其中有12个LdecOBPs基因(LdecOBP2, LdecOBP4, LdecOBP6, LdecOBP9, LdecOBP10, LdecOBP12, LdecOBP13, LdecOBP16, LdecOBP20-22和LdecOBP24)在触角中高表达,2个LdecOBPs基因(LdecOBP5和LdecOBP17)在足中高表达,其他12个LdecOBPs基因(LdecOBP1, LdecOBP3, LdecOBP7, LdecOBP8, LdecOBP11, LdecOBP14, LdecOBP15, LdecOBP18, LdecOBP19, LdecOBP23, LdecOBP25和LdecOBP26)在触角、头(去除触角)、胸、腹、足和翅这些组织中均表达。【结论】本研究结果为进一步研究马铃薯甲虫嗅觉识别分子机制奠定了基础。     

Predation induced changes in behavior and growth rate in three populations of the intertidal snail, Littorina sitkana (Philippi)

We investigated the sublethal effects of a predatory crab, Cancer productus (Randall), on the behavior and growth of its snail prey, Littorina sitkana, by setting up controlled rearing and prey-size selection experiments. L. sitkana were collected from three sites on San Juan Island, WA, USA. These sites varied in snail size, abundance, and vertical distribution, and in the abundance of the crab predator C. productus. Snails from all three populations were raised for 34 days under the following treatments: no-crab control, a non-feeding C. productus encased in mesh box, and an encased C. productus feeding on L. sitkana. The non-feeding crab treatment did not affect snail foraging behavior or growth rate in comparison with the no-crab control. In contrast, the presence of a feeding crab elicited escape behavior in the snails, halted grazing, and consequently reduced growth rates. A population difference in escape behavior was observed: upward migration in snails from rocky shores and hiding in crevices in snails from a mud flat. It thus appears that chemicals leaching from crushed conspecific snails, rather than the presence of the crab predator, act as the “alarm substance” to which L. sitkana react. The magnitude of the growth depression in the presence of feeding crabs was 85%, with no difference among the three populations. Once the feeding crab stimulus was removed, snails in all populations resumed normal growth, suggesting that this response to feeding predators is reversible with changing environmental conditions. Laboratory experiments were set up to determine if all size classes of L. sitkana are equally susceptible to C. productus predation. C. productus consistently selected the largest of three size classes of L. sitkana. These results suggest that slow growth rate and small size in L. sitkana may actually be an adaptation for coexisting with high C. productus abundance, rather than simply a cost of escape behavior.     

In vitro antiprotozoal activity of the lipophilic extracts of different parts of Turkish Pistacia vera L.

Thirteen lipophilic extracts prepared with n-hexane from various parts of Pistacia vera L. tree (Anacardiaceae) growing in Turkey were screened for their in vitro activity against four parasitic protozoa, Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani and Plasmodium falciparum. Melarsoprol, benznidazole, miltefosine, artemisinin and chloroquine were used as reference drugs. The cytotoxic potentials of the extracts on rat skeletal myoblast (L6) cells were also assessed and compared to that of podophyllotoxin. The screening method employed was medium-throughput, where the extracts were tested at two concentrations, at 0.8 and 4.8 μg/ml (T. brucei rhodesiense, L. donovani and Plasmodium falciparum), or at 1.6 and 9.7 μg/ml (T. cruzi and L6 cells). At 4.8 μg/ml concentration, the branch extract of Pistacia vera (PV-BR) significantly inhibited (77.3%) the growth of L. donovani, whereas the dry leaf extract (PV-DL) was active against Plasmodium falciparum (60.6% inhibition). The IC₅₀ values of these extracts were determined as 2.3 μg/ml (PV-BR, L. donovani) and 3.65 μg/ml (PV-DL, Plasmodium falciparum). None of the extracts possessed cytotoxicity on mammalian cells.     

The Biology and Host Range of Falconia intermedia (Hemiptera: Miridae), a Potential Biological Control Agent for Lantana camara (Verbenaceae) in Australia

The life history and host specificity of Falconia intermedia in Australia were investigated. Adults and nymphs feed on the intercellular tissue on the underside of Lantana camara leaves. Eggs are deposited singly or in small clusters alongside veins and, on average, hatch in 12 days. Development to adult takes about 15 days and there are 5 instars. Females live for approximately 30 days and lay an average of 1.5 eggs/day. Oviposition occurred on all five L. camara phenotypes tested but subsequent development was significantly poorer on the pink-flowering phenotype. Forty-six plant species were tested to determine host specificity. The only species upon which adults fed and oviposited were L. camara and another introduced weed, Lippia alba. Both plant species supported populations of F. intermedia over several generations. F. intermedia did not display any predatory behaviour towards eggs, nymphs or larvae of either Aconophora compressa or Ectaga garcia, two other introduced biocontrol agents of L. camara. F. intermedia was approved for release in Australia in 2000.     

Morphological and morphometric study of crustacean parasites within the genus Lernaeocera

Two species of Lernaeocera are present in the southeastern North Sea. Lernaeocera lusci infects bib Trisopterus luscus, dragonet Callionymus lyra and sand goby Pomatoschistus minutus. L. Minuta is a junior synonym of L. lusci. The second valid species, L. branchialis, infects whiting Merlangius merlangus. The two species can be morphologically separated by the antennary processes, which are present in L. lusci and absent in L. branchialis. Discriminant functions allow complete separation between L. lusci and L. branchialis. There is high intraspecific, host-dependent variability within L. lusci. Length of L. lusci is significantly influenced by host size, and body form is influenced by the site of attachment of L. lusci on at least one host (bib). It is suggested that L. lusci consists of 3 forms: f. lusci, f. minuta and f. lyra.     

Antimicrobial activity of aqueous extracts of Larrea divaricata Cav (jarilla) against Helicobacter pylori

We studied here the effect of aqueous extracts of Larrea divaricata Cav on the growth of Helicobacter pylori. Results show that cold extract, infusion, decoction and simulated digestion had inhibitory activity at 0.04–0.1 mg/l against clarithromycin and metronidazole susceptible and resistant H. pylori strains. These results support the popular use of L. divaricata Cav in gastric disturbances and prompt further research to characterize these compounds with a therapeutic potential against gastric ulcers and gastric cancer associated with H. pylori.     

Antioxidants and antioxidative enzymes in wild-type and transgenic Lycopersicon genotypes of different chilling tolerance

The Mehler–Ascorbate–Peroxidase cycle is a protection system against reactive oxygen species (ROS) occurring during over-excitation of the photosynthetic apparatus. In the cultivated tomato, Lycopersicon esculentum, long-term chilling under moderate light leads to oxidation of the Calvin cycle key enzyme, ribulose-1,5-bisphosphate carboxylase (rubisco), presumably by generation of ROS. In contrast, high-altitude lines of the wild tomato species L. peruvianum were tolerant against the same chilling stress. In the present study, we analysed leaf contents of antioxidants (ascorbate, glutathione) and activities of enzymes of the Mehler–Ascorbate–Peroxidase cycle in the two Lycopersicon species. While antioxidant levels and activities of chloroplast superoxide dismutase (SOD) and ascorbate peroxidase (APX), both inducible by chilling stress, were similar in chilling-tolerant and chilling-sensitive genotypes, chilled L. esculentum showed lower glutathione reductase (GR) activities than high-altitude L. peruvianum. We constructed transgenic plants overexpressing an Escherichia coli GR in the chloroplast (approximately 60-fold of the wild-type (WT) activity). However, these plants resembled identical chilling sensitivity of the photosynthetic apparatus as WT plants as measured after a photoinhibition treatment and by the effect of long-term chilling on rubisco activity. We conclude that the Mehler–Ascorbate–Peroxidase cycle is not the limiting factor for the sensitivity of the photosynthetic apparatus of L. esculentum towards long-term chilling under moderate light. We suggest that a possible cause for the higher chilling tolerance of L. peruvianum is prevention of ROS formation by better conversion of light energy to photochemistry at suboptimal temperatures.     

Potential of selected lactic acid bacteria to produce food compatible antifungal metabolites

The aim of this study was to assess the potential of lactic acid bacteria to inhibit the outgrowth of some common food-spoiling fungi. Culture supernatants of 17 lactic acid bacterial strains as well as of three commercial probiotic cultures were evaluated for antifungal activity using an agar-diffusion method. The method parameters were chosen in order to reveal compounds for potential use in food (bio)preservation. Thirteen strains showed antifungal activity of which five strains were very promising: Lactobacillus acidophilus LMG 9433, L. amylovorus DSM 20532, L. brevis LMG 6906, L. coryniformis subsp. coryniformis LMG 9196 and L. plantarum LMG 6907. Four of these five strains were further examined; it was found that the produced antifungal metabolites were pH-dependent. The exact chemical nature of these substances has not been revealed yet.     

巴茅草水浸提液对3种作物种子萌发及幼苗生长的化感作用

本文以发芽率、发芽速度指数、发芽指数、根长、茎长和生物量为种子萌发和幼苗生长参数,研究不同生长时期巴茅草叶片和茎秆水浸提液对白菜、生菜、水稻的化感作用。结果表明: 巴茅草叶水浸提液化感作用强于茎秆水浸提液,叶水浸提液处理后受体植物的发芽指数和生物量均显著低于茎水浸提液。枯萎期巴茅草的化感作用强于生长旺盛期。不同浓度巴茅草叶水浸提液对3种作物的化感作用存在明显的量效关系,浸提液浓度越高,巴茅草的化感抑制作用越强。巴茅草叶水浸提液对白菜和生菜各萌发指标100%抑制的浓度分别为0.075和0.10 g·mL^-1;而0.10 g·mL^-1巴茅草叶水浸提液对水稻发芽率、发芽速度指数、发芽指数的抑制率分别为13.8%、27.2%、19.3%。巴茅草叶水浸提液对白菜和生菜各生长指标100%抑制的浓度分别为0.05和0.10 g·mL^-1;而0.10 g·mL^-1巴茅草叶水浸提液对水稻根长、茎长、生物量的抑制率分别为64.6%、92.9%、21.8%。结合种子萌发和幼苗生长的综合化感指数,3种供试作物对巴茅草化感作用的敏感程度为白菜>生菜>水稻。     

舟山渔场产卵场保护区春季小黄鱼群体结构及资源动态

根据2014—2019年舟山渔场产卵场保护区及邻近海域底拖网调查资料,分析了春季小黄鱼的群体结构、资源密度变化及其与环境因子的关系。结果表明: 小黄鱼的体长-体重关系式为: W=0.44×10^-4×L^2.78,b值<3,说明近年来小黄鱼为负异速生长,肥满度与体长呈负相关,身体趋于细长。2014—2019年小黄鱼的体长和体重均以2014年最高、2019年最低。2014年以来,舟山渔场产卵场保护区及邻近海域小黄鱼的群体规格逐渐减小,说明近年来小黄鱼个体小型化现象并未改善。与产卵场保护区设立前的数据相比,保护区建立后小黄鱼资源密度有所提升,表明保护区管护对小黄鱼的资源恢复起到了一定的保护作用。GAM模型拟合结果显示,与保护区及周边海域小黄鱼资源密度分布关系密切的环境因子主要是水深和底层水温。随着水深的增加,小黄鱼资源量呈波动上升趋势,在水深60 m附近时资源量最高;在12~16 ℃水温范围内,小黄鱼资源量随底层水温升高而增大;当水温>16 ℃时,其资源量随底温的上升而下降。     

洁丽香菇胞外粗多糖对小鼠移植性S180肉瘤的抑制作用和免疫功能调节

对洁丽香菇胞外粗多糖中多糖和蛋白含量进行测定,其中多糖含量为21.87%,蛋白含量为7.14%。通过体内实验研究该多糖对S180肉瘤的生长抑制作用。结果表明洁丽香菇胞外粗多糖高、中、低剂量组均能不同程度抑制S180 肉瘤的生长,其中高剂量组（500mg/kg）抑瘤率最高（为39.44%）,同时能显著增加胸腺指数,降低脾指数,有效改善免疫器官受损现象;中、低剂量（250mg/kg,125mg/kg）亦能抑制肿瘤生长,抑瘤率分别为30.43%和23.40%。实验中采用ELISA法对血清中各种细胞因子含量进行测定,结果表明洁丽香菇胞外粗多糖高剂量组可明显诱导血清中TNF-α、IL-12的分泌,低剂量组可诱导IFN-γ、IL-10的分泌。由此认为洁丽香菇胞外粗多糖通过恢复免疫器官功能,增加血清中TNF-α、IL-12、IFN-γ和IL-10的含量,从而达到增强细胞免疫的作用,发挥抗肿瘤活性。