PSEUDOBRYOPSIS MYURA AND ITS REPRODUCTION

Pseudobryopsis myura, type of the genus, is monoecious; male and female gametocysts occur on the same plant; there is definite anisogamy and only macrogametes possess a stigma. The mode of extrusion of the gametes differs both from the Bryopsis-type and from the Codium-type. As in Codium the discharge of the gametocyst is due to internal pressure. Gametes become motile only after their extrusion from the gametocyst.     

Small-sized euryhaline fish as intermediate hosts of the digenetic trematodeCryptocotyle concavum

Cercariae of the trematodeCryptocotyle concavum, which encyst in skin and/or kidney of sticklebacks and gobies, were studied in the Schlei Fjord (western Baltic Sea). Mean incidence of dermal cysts was 48 % inGasterosteus aculeatus and 37 % inPungitius pungitius. No cysts were found in the kidneys of sticklebacks. While 97 % ofPomatoschistus microps had encysted metacercariae in the kidneys, only 2 % had cysts in the skin.Pomatoschistus minutus, however, showed hardly any cyst infestation of either skin or kidney. InP. microps the intensity of infestation by metacercariae was frequently more than 50 cysts; in contrast, sticklebacks rarely exhibited more than 5 dermal cysts. Infested fish were larger than 10 mm in total length, the incidence rate increasing with growth. Parasitic infestation depends on ambient salinity:C. concavum was not found at salinities below 4 . In contrast to the high incidence in fish, the first hosts — the snailsHydrobia stagnalis andH. neglecta — showed remarkably low infection rates (3 to 5 %). The findings reported are related to the distribution ofC. concavum, the mode of life of infested fish, the feeding habits of the final hosts and the infestation ofP. microps by other parasites. Evidently,P. microps represents an optimal second host forC. concavum.     

乙酸钠调控小球藻生长及代谢产物

【背景】小球藻是一种单细胞绿藻,在不同培养条件下可积累高附加值的代谢产物,这些产物可用于生产生物燃料、食品、保健品、药品等。然而这些代谢产物在藻细胞中的生产率较低且很难通过经济可行的方法将其分离,这使其工业化规模生产受到限制。【目的】研究乙酸钠对小球藻生物量的影响,并分析其对小球藻代谢产物的调控作用。【方法】通过在小球藻培养液中添加不同浓度的乙酸钠(1.0、2.0、3.0、4.0、5.0 g/L),研究其调控小球藻生长和代谢的作用机理。【结果】在添加3.0 g/L乙酸钠的培养液中,小球藻的生物量是对照组的5.2倍,尽管藻细胞中蛋白质含量无明显变化,但油脂和类胡萝卜素含量是对照组的2.4倍和1.2倍,多糖和叶绿素a含量却仅为对照组的54.6%和54.4%。【结论】乙酸钠不仅会影响藻细胞的生长,还会调控其代谢过程,这为深入探索乙酸钠在调控小球藻生长及代谢过程的作用机制提供了理论基础和技术资料。     

On relations between sets: III

The theory of relations between sets, proposed and outlined in previous publications (Bull. Math. Biophysics,23, 233–235, 1961;28, 117–124, 1966;28, 309–313, 1966), is tentatively expanded and generalized with a view to biological applications.     

Hoya peninsularis (Apocynaceae,Asclepiadoideae), a new species from Peninsular Malaysia,and notes on Hoya maingayi and Gongronema wrayi

A new species of Hoya from the western part of Peninsular Malaysia is described and illustrated as H. peninsularis. It has long been confused with Hoya finlaysonii because both have leaves with prominent darker venation, but can be distinguished on the corona lobe size and corolla pubescence. In addition, Hoya maingayi, a species earlier considered ‘doubtful and excluded' is typified and illustrated for the first time, and its distribution is shown to extend to Thailand. Gongronema wrayi is recognised as an earlier name and a new synonym for Hoya omlorii, a species previously considered to occur only in Borneo and Sumatra. The name is typified. An updated checklist of Hoya of Peninsular Malaysia is provided.     

Screening and identification of yeast strains from fruits and vegetables: Potential for biological control of postharvest chilli anthracnose (Colletotrichum capsici)

Yeasts antagonistic to Colletotrichum capsici were isolated from Thai fruits and vegetables. Four antagonists (R13, R6, ER1, and L2) were found that inhibited C. capsici growth with biocontrol efficacies of 93.3%, 83.1%, 76.6%, and 66.4%, respectively. Identification by 26S rDNA, and ITS region sequence together with physiological and morphological characteristics, showed them to be Pichia guilliermondii, Candida musae, Issatchenkia orientalis, and Candida quercitrusa, in order of their efficacy. P. guilliermondii strain R13 showed efficacy in reducing disease incidence on C. capsici infected chilli fruits to as low as 6.5%. Lower disease incidence was observed at lower storage temperature. The application of P. guilliermondii is more effective for preserving chilli fruits than conventional preservation with chlorinated water.     

Identification of Polygonum orientale constituents using high-performance liquid chromatography high-resolution tandem mass spectrometry

Our primary focus in this research was to identify and characterize its bioactive compounds for potential therapeutic use. Twenty-seven metabolites of Polygonum orientale were identified using LC-QTOF tandem mass spectrometry. Interestingly, P. orientale extracts included several highly oxygenated flavonoids were isolated from P. orientale by column chromatography. ¹³C NMR data of highly oxygenated flavonoids (1–7) are reported here for the first time. In addition, nitric oxide, 1,1-diphenyl-2-picrylhydrazyl, and water-soluble tetrazolium salt assays were carried out on the isolated compounds to investigate their anti-inflammatory, anti-oxidant, and neuroprotective activities, respectively. Compounds 1, 2, 3, 5, 7, and 8 significantly attenuated lipopolysaccharide-stimulated NO production in BV2 cells without affecting cell viability. Compounds 9–12 exhibited significant antioxidant activity, while compounds 8, 9, and 12 exhibited protective effects against glutamate-induced neurotoxicity in HT22 cells. Our results indicate that P. orientale is a promising source of natural agents for the potential treatment of inflammation and neurodegenerative diseases.     

Autecologia di Ulva rigida: 1. Influenza dell'intensità luminosa e della temperatura sulla produzione di ossigeno

Abstract

Autecology of Ulva rigida C. Ag.: 1. Influence of light intensity and temperature on oxygen production. The photosynthetic activity of Ulva rigida, growing in Bari's harbour (Adriatic Sea), has been assessed in the laboratory by measuring oxygen evolution as a function of white light intensities. Tests were performed at four temperatures. The data indicate the remarkable amount of O₂ released in the environment.     

Hatching enzyme immunolocalization during embryonic development of the ascidians Ciona intestinalis and Phallusia mammillata

Summary

Different stages of the embryonic development of the ascidians, Ciona intestinalis and Phallusia mammillata, were observed by confocal microscopy after treating embryos with polyclonal antibody raised against C. intestinalis hatching enzyme and after staining with FITC-conjugated second antibody. In both species fluorescence is localized, at the gastrula stage, in the ectoderm. At the subsequent neurula and tail bud stages, in C. intestinalis, the enzyme is localized in the anterior region and tail region, while in P. mammillata it is only present in the anterior region.     

Could phenotypic plasticity limit an invasive species? Incomplete reversibility of mid-winter deacclimation in emerald ash borer

The emerald ash borer (Agrilus planipennis, Coleoptera: Buprestidae) is a wood-boring invasive pest devastating North American ash (Fraxinus spp.). A. planipennis overwinters primarily as a freeze-avoiding prepupa within the outer xylem or inner bark of the host tree. The range of this species is expanding outward from its presumed introduction point in southwestern Michigan. We hypothesized that loss of cold tolerance in response to mid-winter warm spells could limit survival and northern distribution of A. planipennis. We determined whether winter-acclimatised A. planipennis prepupae reduced their cold tolerance in response to mid-winter warm periods, and whether this plasticity was reversible with subsequent cold exposure. Prepupae subjected to mid-winter warm spells of 10 and 15°C had increased supercooling points (SCPs) and thus reduced cold tolerance. This increase in SCP was accompanied by a rapid loss of haemolymph cryoprotectants and the loss of cold tolerance was not reversed when the prepupae were returned to −10°C. Exposure to temperatures fluctuating from 0 to 4°C did not reduce cold hardiness. Only extreme warming events for several days followed by extreme cold snaps may have lethal effects on overwintering A. planipennis populations. Thus, distribution in North America is likely to be limited by the presence of host trees rather than climatic factors, but we conclude that range extensions of invasive species could be halted if local climatic extremes induce unidirectional plastic responses.     

Relational forces and structures produced by them

After giving a brief review of the theory of organismic sets (Bull. Math. Biophysics,29, 139–152, 1967;31, 159–198, 1969), in which the concept of relational forces, introduced earlier (Bull. Math. Biophysics,28, 283–308, 1966a) plays a fundamental role, the author discusses examples of possible different structures produced by relational forces. For biological organisms the different structures found theoretically are in general agreement with observation. For societies, which are also organismic sets as discussed in the above references, the structures can be described only in an abstract space, the nature of which is discussed. Different isomorphisms between anatomical structures, as described in ordinary Euclidean space, and the sociological structures described in an abstract space are noted, as should be expected from the theory of organismic sets.     

SPECIES-SPECIFIC SOUNDS IN WATER BUGS OF THE GENUS MICRONECTA. PART 2, CHORUSING

ABSTRACT

Although chorusing behaviour has been reported previously in six species of corixid water bugs, including one European species of Micronecta, no analysis of chorusing has been published for Micronecta. Studies of a large pond in SE Australia show that chorusing occurred in the most common species of Micronecta in the study area, M. concordia. Pulse-trains synchronized with those of other individuals nearby were the predominant acoustic output of M. concordia males throughout the stridulating season, from mid-winter to mid-summer. At the start of the season, chorusing began with an exponential increase in the percentage of synchronized signals over a period of six days.     

荧光假单胞菌2P24中opgGH基因影响抗生素2,4-二乙酰基间苯三酚的产生

【目的】抗生素2,4-二乙酰基间苯三酚(2,4-diacetylphloroglucinol,2,4-DAPG)是生防菌株荧光假单胞菌(Pseudomonas fluorescens) 2P24防治植物病害的关键因子,然而对2,4-DAPG生物合成的调控通路并未完全解析。【方法】前期利用Tn5随机突变的方法获得一株对棉花立枯丝核菌(Rhizoctonia solani)拮抗能力完全丧失的突变菌株W3,本研究利用基因互补等方法研究该突变体中被破坏的基因对菌株2P24分泌2,4-DAPG和其他生防相关性状的影响。【结果】Tn5插入位点及其序列分析表明突变菌株W3中Tn5破坏了opgG基因。鉴于opgG和opgH基因组成操纵子,利用同源重组技术构建了opgGH内缺失突变菌株。与野生菌株2P24相比,opgGH突变菌株中2,4-DAPG的产量显著降低。对其他生防相关性状的检测发现,突变opgGH基因并不影响群体感应系统(quorum sensing,QS)信号分子的产生、氢氰酸的产生以及生物膜的形成,但可抑制菌株2P24的游动性。转录融合实验进一步表明opgGH基因并不调控gacA基因及其调控...     

Incidence of resistance to tetracycline,chloramphenicol and ampicillin amongSalmonella species isolated in The Netherlands in 1965 and 1966

In 1965 and 1966 respectively 9628 and 10467Salmonella strains were screened for resistance to tetracycline and chloramphenicol. In 1965 the major half of the strains were also tested for ampicillin resistance and in 1966 all strains passed this test. In 1965 20.9% and in 1966 21.7% were found resistant, mainly to tetracycline. The incidence of resistance to chloramphenicol remained low (less than 1%). By far the majority of the resistant strains belonged toS. typhi murium andS. panama. The rate of resistance in the former organism remained nearly equal to that observed in 1963 – 1964, whereas inS. panama it has diminished.Ampicillin-resistant strains were found in as many as 23 different types ofSalmonella. In 8 types in which ampicillin resistance was found, only animal strains were concerned. These findings may represent cases of primary ampicillin resistance. In the human strains ofSalmonella the incidence of ampicillin resistance increased from 11.6% in 1965 to 15.3% in 1966.     

Lankesteria barretti n. sp. (Eugregarinida,Diplocystidae), a Parasite of the Mosquito Aedes triseriatus (Say) and a Review of the Genus Lankesteria Mingazzini*

SYNOPSIS. Lankesteria barretti n. sp. (Eugregarinida, Diplocystidae) is named from the mosquito Aedes triseriatus in Texas. The young cephalins occur within the midgut epithelial cells. When they reach a length of about 150–200 μ they rupture the host cell and are released into the space between the epithelium and the peritrophic membrane, becoming gamonts. These grow to about 140–310 by 40 μ at the anterior end and 12 μ at the posterior end. When the host pupates they enter the lumen of the Malpighian tubules; pairs join in syzygy by their anterior ends and later more laterally. Each pair forms a spherical gametocyst about 60–100 μ (exceptionally 250 μ) in diameter. A large number of oocysts develop in each gametocyst. The mature oocysts are spindle-shaped, 11 by 5.4–5.7 μ, and contain 8 elongate sporozoites and a refractile residuum. The gametocyst wall breaks down, releasing oocysts in the Malpighian tubules of the host when it is adult. The oocysts pass out in the feces and presumably infect new larvae by ingestion. The cephalins and gamonts of L. barretti differ from those of L. culicis (of Aedes aegypti) in having a relatively anterior instead of a central nucleus and in lacking a noticeable mucron; its longitudinal folds are not as well-developed as in L. culicis, and its paraglycogen granules are larger. The fine structure of L. culicis and L. barretti is described in detail. Their gamonts have a polar ring but no definite conoid. The taxonomy of the genus is reviewed, but its species have been so poorly described that it is impossible to be sure whether they are all really Lankesteria. About 19 species have been described (5 from turbellaria, 8 from tunicates, perhaps 1 from Amphioxus, 1 from the chaetognath Sagitta sp., 1 from Phlebotomus and 3 from mosquitoes).     

Trematode fauna (Platyhelminthes: Digenea) of some sea ducks wintering on the southern Baltic coast (NW Poland) – a general comparison

The common scoter Melanitta nigra, velvet scoter M. fusca and long-tailed duck Clangula hyemalis (Aves: Anatidae) are among the more abundant sea ducks on the southern coast of the Baltic in winter, but their parasitic trematode fauna (Platyhelminthes, Digenea) in this region is little known. The aim of this study, conducted in 2007–2009, was a general comparison of the trematode fauna of these ducks in NW Poland. The prevalence and intensity of trematode infection were 68.3% and 119.9 in common scoter (101 examined), 77.6% and 13.1 in velvet scoter (58 examined) and 70.6% and 23.7 in long-tailed duck (68 examined). The following trematodes were found: Diplostomum pungitii, Apatemon gracilis, Australapatemon minor, Typhlocoelum sisowi, Echinochasmus spinulosus, Echinoparyphium recurvatum, Psilostomum brevicolle, Psilotrema simillimum, Catatropis verrucosa, Notocotylus attenuatus, N. gibbus, Paramonostomum alveatum, Prosthogonimus ovatus, Levinseniella propinqua, Gymnophallus bursicola and Cryptocotyle concava. The common scoter differs from the velvet scoter and long-tailed duck in its statistically significantly higher prevalence of G. bursicola; from long-tailed duck in its higher prevalence and greater intensity of infection with P. alveatum; and from velvet scoter in its greater intensity of infection with C. concava. The velvet scoter is distinguished from the long-tailed duck by its greater intensity of infection with P. brevicolle, lower prevalence of L. propinqua and lower intensity of infection with C. concava. Links between the differences found and the biology and ecology of the hosts, as well as the means of transmission of the parasites, are also discussed.     

Food diversity and niche-overlap of sympatric tits (Great Tit,Parus major,Blue Tit,Cyanistes caeruleus and Coal Tit Periparus ater) in the Hyrcanian Plain forests

Abstract

This study was carried out between early summer 1998 and late summer 1999 in the Hyrcanian Plain forests, the southern Caspian Sea woodlands. In total, the gizzard contents of 241 specimens of the Great Tit (Parus major Linnaeus, 1758), Blue Tit (Cyanistes caeruleus Linnaeus, 1758), and Coal Tit (Periparus ater (Linnaeus, 1758)) were collected so that the percentages of grit, plants and animal materials could be estimated and the plant and invertebrate species consumed identified. The data were tested by a series of Mann-Whitney U, ANOVA and Kruskal-Wallis tests. To survey niche overlap of food materials between species and season, the symmetrical overlap index developed by Pianka (1973) was used. The most important invertebrates (maximum of percentage per season) in the diet of P. major were Coleoptera (36.5%) and Lepidoptera (33.6%), for C. caeruleus Coleoptera (34.5%) and Araneae (31.2%), and for Pe. ater Coleoptera (38.2%) and Araneae (35.6%). The most important plants consumed by P. major were Sorghum halepense (68.7%) and Ficus carica (65.6%), by C. caeruleus were F. carica (67.5%) and Alnus glutinosa (39.4%), and by Pe. ater were Lonicera spp. (82.9%). There was a greater degree of overlap and competition for animal food, but plant feeding overlap among the three tit species was low. Two species, P. major and C. caeruleus, showed high feeding overlap for animal items (0.92), whereas Pe. ater and C. caeruleus had no significant feeding overlap. The Coal Tit had a greater tendency to forage for vegetable matter and P. major had a greater tendency to forage for animal matter. Analysis of gizzard contents of P. major and Pe. ater showed that, despite the high degree of feeding overlap, the extent of plant materials consumed indicated no significant competition between the two species. Because Pe. ater is present mostly in autumn and winter, this study cannot establish any degree of competition and food-niche overlap during the breeding season between this and other tit species.     

Patulin and aflatoxin in brown rot lesion of apple fruits and their regulation

Aspergillus flavus, A. niger, Penicillium expansum and Rhizopus stolonifer were the most frequently isolated fungi from healthy apple fruits. Alternaria alternata was the most common organism of rotten apple fruits, followed by A. niger, A. flavus, P. expansum and R. stolonifer. The prevalent type of decay, brown rot lesion, is caused by R. stolonifer followed by A. flavus, A. niger, A. alternata and P. expansum. Sodium hypochlorite had good curative properties against fruit rots. The main natural mycotoxins produced in rotten apple were patulin and aflatoxins. The optimum temperature for patulin production by P. expansum was 15 °C after 15 days. Complete inhibition of patulin formation was attained using 0.2% lemon oil and > 90% inhibition using 0.05% lemon and 0.2% orange oils. Also significant inhibition (> 90%) of aflatoxin production was observed with 0.2% lemon oil. This revised version was published online in July 2006 with corrections to the Cover Date.     

Occurrence and distribution of entomophthoralean fungi infecting aphids in mainland China

Seventeen species of entomophthoralean fungi infecting 15 species of aphids have been reported from mainland China. They belong to seven genera: Batkoa, Conidiobolus, Entomophthora, Neozygites, Pandora, Tarichium and Zoophthora. C. thromboides, E. planchoniana, N. fresenii and P. neoaphidis have the widest distributions covering five regions with the exception of the south-west. Tarichium atrospermum and Z. canadensis were only reported in the eastern region and P. echinospora only in the mid-southern region. Pandora neoaphidis, the most common species, occurred in many aphid populations. Species belonging to the genus Conidiobolus frequently appeared in the warm summer season, however, disease incidence was lower compared to the genus Pandora.     

3-Arylidene-5-(4-isobutylphenyl)-2(3H)-furanones: a new series of anti-inflammatory and analgesic compounds having antimicrobial activity

An ideal anti-inflammatory drug should have the desired effect in minimum dose with minimum side effects. Antimicrobial actions associated with such agents will be an added advantage as they broaden the spectrum of the compounds. Promising anti-inflammatory and antimicrobial activity together with low ulcerogenic properties of some 2(3H)-furanones, synthesized in our previous study, prompted us to investigate the effect of the isobutyl group on their pharmacological profile. Since compounds 3, 9, 13, and 14 have both anti-inflammatory and analgesic effects in addition to low ulcerogenic incidence, they were selected for investigation of their inhibitory effects on various cyclo-oxygenase enzymes. It was found that they were more selective toward COX-2 enzymes. An MIC of 6.25 μg/mL was recorded for compounds 3, 13, and 14 against S. aureus, E. coli, R. oryza, and P. citrum. The study supports the development of furanone derivatives as potential anti-inflammatory agents with antimicrobial activity.