Effect of chromium(III) on poly(dG-dC) conformation

The interaction of chromium(III) with poly(dG-dC) inhibits the B to Z transition and results in the condensation of the polymer at high Cr/nucleotide ratios. At low Cr/nucleotide ratios chromium(III) enhanced the ability of ethanol to induce the B to Z transition of poly(dG-dC). The effects of chromium(III) on the conformation of DNA may be related to the carcinogenicity of chromium compounds.     

The species of Ardeicola (Phthiraptera) on Threskiornis (Aves)

The species of Ardeicola parasitic on the Ibis genus Threskiornis are reviewed-clayae Brelih, freemani sp.n., ibis Le Souef & Bullen, indicus Brelih, intermedia sp.n., nippon Hajela & Tandan-and a key for their identification is presented. Notes on the affinities of the species and a discussion on the distribution of Ardeicola on Threskiornis are included.     

The species of Ibidoecus (Phthiraptera) on Threskiornis (Aves)

The species of Ibidoecus parasitic on the Ibis genus Threskiornis are reviewed-clausus (Giebel), dianae Tandan, insularis sp.n., tandani sp.n., threskiornis Bedford-and a key for their identification presented. The host and geographical distribution of the phthirapteran parasites of this genus are discussed.     

西藏珍珠茅属(莎草科)植物增补

发现了分布于西藏的2个珍珠茅属新记录种:小型珍珠茅和毛果珍珠茅,并补充记载了2个新记录种的文献和标本引证。     

铁线莲属研究随记(VI)(英文)

讨论了Clematis eriopoda Maxim.和sect.Atragenopsis Boiss.的地位,认为这二分类群均应成立;描述了2新种,1新变种;过去长期被归并的卷萼铁线莲C.tubulosa得到恢复;Clematisheracleifoliavar.ichangensis被转移改作卷萼铁线莲的变种;首次给出光叶铁线莲Clematisglabrifolia的果实的形态描述。     

Growth of Pseudomonas mendocina on Fe(III) (hydr)oxides

Although iron (Fe) is an essential element for almost all living organisms, little is known regarding its acquisition from the insoluble Fe(III) (hydr)oxides in aerobic environments. In this study a strict aerobe, Pseudomonas mendocina, was grown in batch culture with hematite, goethite, or ferrihydrite as a source of Fe. P. mendocina obtained Fe from these minerals in the following order: goethite > hematite > ferrihydrite. Furthermore, Fe release from each of the minerals appears to have occurred in excess, as evidenced by the growth of P. mendocina in the medium above that of the insoluble Fe(III) (hydr)oxide aggregates, and this release was independent of the mineral's surface area. These results demonstrate that an aerobic microorganism was able to obtain Fe for growth from several insoluble Fe minerals and did so with various growth rates.     

Growth of Pseudomonas mendocina on Fe(III) (Hydr)Oxides

Although iron (Fe) is an essential element for almost all living organisms, little is known regarding its acquisition from the insoluble Fe(III) (hydr)oxides in aerobic environments. In this study a strict aerobe, Pseudomonas mendocina, was grown in batch culture with hematite, goethite, or ferrihydrite as a source of Fe. P. mendocina obtained Fe from these minerals in the following order: goethite > hematite > ferrihydrite. Furthermore, Fe release from each of the minerals appears to have occurred in excess, as evidenced by the growth of P. mendocina in the medium above that of the insoluble Fe(III) (hydr)oxide aggregates, and this release was independent of the mineral's surface area. These results demonstrate that an aerobic microorganism was able to obtain Fe for growth from several insoluble Fe minerals and did so with various growth rates.     

Influence of collagen and chondroitin sulfate (CS) coatings on poly-(lactide-co-glycolide) (PLGA) on MG 63 osteoblast-like cells

Poly-(lactide-co-glycolide) (PLGA) is an FDA-approved biodegradable polymer which has been widely used as a scaffold for tissue engineering applications. Collagen has been used as a coating material for bone contact materials, but relatively little interest has focused on biomimetic coating of PLGA with extracellular matrix components such as collagen and the glycosaminoglycan chondroitin sulfate (CS). In this study, PLGA films were coated with collagen type I or collagen I with CS (collagen I/CS) to investigate the effect of CS on the behaviour of the osteoblastic cell line MG 63. Collagen I/CS coatings promoted a significant increase in cell number after 3 days (in comparison to PLGA) and after 7 days (in comparison to PLGA and collagen-coated PLGA). No influence of collagen I or collagen I/CS coatings on the spreading area after 1 day of culture was observed. However, the cells on collagen I/CS formed numerous filopodia and displayed well developed vinculin-containing focal adhesion plaques. Moreover, these cells contained a significantly higher concentration of osteocalcin, measured per mg of protein, than the cells on the pure collagen coating. Thus, it can be concluded that collagen I/CS coatings promote MG 63 cell proliferation, improve cell adhesion and enhance osteogenic cell differentiation.     

The distribution of lice (Phthiraptera) on poultry (Gallus domesticus)

The distribution of three amblyceran (Menacanthus stramineus, Menacanthus cornutus, Menopon gallinae) and five ischnoceran species (Lipeurus lawrensis tropicalis, Lipeurus caponis. Goniocotes gallinae, Goniodes gigas, Goniodes dissimilis) on poultry was determined. The preferred sites of these species on the host body were recorded.     

Observations on Neotropical Rainpools (Bolivia) with emphasis on Chironomidae (Diptera)

Nine rainpools in the savanna of northern Bolivia were examined using a random, semi‐quantitative sampling method. Both the macrophyte and insect assemblages showed that the longevity of a pool tended to be the dominant influence on the colonizing biota in the Tropics. Twenty‐four families of insects were recorded, including seven Heteroptera, five Odonata and five Diptera. The highly ephemeral (A‐)pools, which were dominated by beetles, differed from longer‐lived waters (B‐ and C‐pools). The composition of the insect assemblages in the B‐ and C‐pools formed a continuum, and the Chironomidae became more numerous and diverse with increasing water body longevity and habitat complexity. Out of the 20 recorded chironomid genera, three uncommon larval types are presented (Chironomini Gen X, "Tanytarsus”; (b), "Tanytarsus”; (dark L.o.). The study area is among the least researched in Bolivia, so many insects, and the chironomids in particular, are suspected as being newly discovered species.     

Effect of culture media on virulence of Hirsutella thompsonii (Fischer) (Deuteromycetes) to control Brevipalpus phoenicis (Geijskes) (Acari: Tenuipalpidae)

The virulence of Hirsutella thompsonii (Fischer) to Brevipalpus phoenicis (Geijskes) was evaluated in laboratory, grown on complete and solid culture media (MC-S); complete and liquid culture media (MC-L); rice (APC) and powdered rice (APC-SM). Adults were confined to arenas prepared with citrus leaves in acrylic dishes containing water-agar. Conidial suspensions were prepared at different concentration (3.2 x 10(5) to 1 x 10(7) spores/ml) and applied on mites to establish the table curve-response on fourth day. For field evaluation, adults were maintained in arenas prepared with fruits which were placed in plants. In this test, four treatments were tried: H. thompsonii cultured on rice (APC) at two concentrations (20 kg/ha and 10 kg/ha), H. thompsonii produced by liquid fermentation (MC-L) (5 L/ha) and control (sterile water). Adult survival, number of eggs and nymphs per fruit were observed 10 and 20 days after the fungus application. The lowest LC25 value calculated was from pathogen produced in MC-S (1.9 x 10(5) conidia/ml).The LC25 values calculated to APC and APC-SM did not differ statistically. The LC25 values to MC-L and MC-S were 1.9 x 10(6) infective cells/ml and 2.2 x 10(5) conidia/ml. In the field, concentration and time to death differed between treatments and control. The applications resulted in reduction of adult survival and number of eggs.     

Biology of Acarophenax lacunatus (Cross & Krantz) (Prostigmata: Acarophenacidae) on Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) and Cryptolestes ferrugineus (Stephens) (Coleoptera: Cucujidae)

The aim of the present study was to assess the effect of six different temperatures on the development of Acarophenax lacunatus (Cross & Krantz) using eggs of Tribolium castaneum (Herbst) and Cryptolestes ferrugineus (Stephens) as hosts. The temperature affected the development of A. lacunatus. The largest values for the progeny (19 mites in T. castaneum and 15 mites in C. ferrugineus) were obtained at about 30 degrees C, as also observed for the net reproductive rate (Ro), which revealed that the A. lacunatus population increased 18 times in T. castaneum and 14 times in C. ferrugineus in a generation. The intrinsic rate of increase (r m) gradually increased with temperature, reaching the maximum value at 35 degrees C in T. castaneum (1,608) and C. ferrugineus (1,289). The generation time was negatively correlated with temperature, ranging from 1,60 to 4,85 days in T. castaneum and from 1,96 to 5,34 days in C. ferrugineus. These results suggest that the mite A. lacunatus may be used in programs of biological control of T. castaneum and C. ferrugineus in the tropics.     

Studies on dipeptidyl(amino)peptidase IV (glycyl-proline naphthylamidase)

Summary The activity of dipeptidyl(amino)peptidase IV (DAP IV, glycylproline naphthylamidase) was discovered in the endothelial cells of the venous part of capillary bed and of small venules of many organs of the rat, mini-pig, rabbit, cock as well as man. In aortae, large arteries and veins only a portion of vase vasorum displays a positive reaction. Glycyl-proline-4-methoxy-2-naphthylamide (Gly-Pro-MNA) is the substrate of choice both from the viewpoint of enzyme kinetics as well as localization. Phenylalanyl-proline-4-methoxy-2-naphthylamide (Phe-Pro-MNA) is cleaved less easily, however, it enables a good localization. 1- and 2-naphthylamine derivatives of glycylproline display better kinetic properties than Phe-Pro-MNA, however they enable a satisfactory localization under special conditions only.The recommended diazonium salt for the routine is Fast Blue B. The enzyme is quite firmly associated with the structure and chloroform-acetone preextraction of cryostat sections does not influence its activity significantly while improving the localization. Block fixation in aldehydes inhibits the enzyme activity (glutaraldehyde more than formaldehyde). The osmificated azo-dye originated of 4-methoxy-2-naphthylamine and Fast Blue B or hexazonium-p-rosaniline is still partially soluble in solvents used for the usual embedding in epoxyresins for electron microscopical examination. This is a drawback for a reliable demonstration of DAP IV in endothelial cells on the electronmicroscopical level using the epoxy-resin technique. DAP IV of the endothelium is inhibited totally by DFP (10^–3M), partially by E 600 (10^–3); and slightly by phenanthroline (10^–3M). It is unaffected by EDTA (10^–3M) and N-ethyl maleimide (10^–3M).The combined demonstration of alkaline phosphatase and DAP IV in the same section renders a reliable demonstration of the capillary bed in many organs.The contribution of DAP IV activity of the capillary endothelium to the total DAP IV activity in a particular organ is decisive in the myocardium, striated muscle, aorta and lung; it represents about one half of the total activity in spleen and pancreas and is less expressed in the liver, intestine and particularly in the kidney.In the jejunum of patients sufferring coeliac sprue the activity of capillary endothelium in the propria is decreased or not demonstrable in the acute stage. After a gluten-free diet it is restituted. The activity of DAP IV does not change significantly in aortae of the rabbit and man with atherosclerosis. In plaques of human aortae the capillary endothelium reacts at the most. Vasa vasorum in the adventitia overlying large plaques, which penetrate into the media, display a high DAP IV activity and their number can be increased. In plaques of arteries of cocks there is a positive DAP IV reaction in foam cells. DAP IV does not belong to the enzymes indicating early changes in atherogenesis.The function of DAP IV in the endothelium is not known. It may be a part of the machinery influeneing the protein part of the endothelial coat or may participate in the degradation of some vasoactive peptides.     

Ultrastructural studies on the vitellogenesis of Tetrodontophora bielanensis (Waga) (Collembola)

Summary Vitellogenesis in Tetrodontophora bielanensis (Waga) is of the mixed type. Part of the yolk material is produced inside the oocyte (auto-synthesis), while part is absorbed by micropinocytosis. During autosynthesis polyribosomes, rough endoplasmic reticulum and dictyosomes take part. Regardless of their origin, mature yolk spheres are constructed identically and are composed of three elements: cortex layer, matrix and crystals. Histochemical tests show that polysaccharides are present in the yolk spheres. Lipid droplets have been observed in the ooplasm; they develop without visible contact with any of the organelles. Among the reserve materials the following have been found: rough endoplasmic reticulum, dictyosomes, polyribosomes, mitochondria and a few microtubules.     

Diplectanids (Monogenea) on the archerfish Toxotes jaculatrix (Pallas) (Toxotidae) off Peninsular Malaysia

Two new and two previously described species of diplectanid monogeneans (Heteroplectanum flabelliforme n. sp., Diplectanum sumpit n. sp., D. jaculator Mizelle & Kritsky, 1969 and D. toxotes Mizelle & Kritsky, 1969) were collected from archerfish Toxotes jaculatrix off the Island of Langkawi, Kedah and off Perak, Malaysia. The reproductive systems and squamodiscs of D. jaculator and D. toxotes are described for the first time. D. sumpit n. sp. differs from D. toxotes and D. jaculator in a having a small curved copulatory tube with a distinct accessory piece, compared to the long, tubular copulatory tube of D. jaculator and the slender tube of D. toxotes. D. sumpit n. sp. also differs from D. toxotes in having a larger ventral bar and larger squamodiscs. H. flabelliforme n. sp. differs from all known Heteroplectanum species in the shape and size of the squamodiscs, the arrangement of the sclerites in the squamodiscs, the extremely large ventral bar and the short, curved, non-spinous copulatory tube.     

Phylogeography of Aedes (Stegomyia) aegypti (L.) and Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae) based on mitochondrial DNA variations

Aedes (Stegomyia) aegypti (l.) and Aedes (Stegomyia) albopictus (Skuse) are the most important vectors of the dengue and yellow-fever viruses. Both took advantage of trade developments to spread throughout the tropics from their native area: A. aegypti originated from Africa and a. albopictus from South-East Asia. We investigated the relationships between A. aegypti and A. albopictus mosquitoes based on three mitochondrial-DNA genes (cytochrome b, cytochrome oxidase I and NADH dehydrogenase subunit 5). Little genetic variation was observed for a. albopictus, probably owing to the recent spreading of the species via human activities. For A. aegypti, most populations from South America were found to be genetically similar to populations from South-East Asia (Thailand and Vietnam), except for one sample from Boa Vista (northern Amazonia), which was more closely related to samples from Africa (Guinea and Ivory Coast). This suggests that African populations of A. aegypti introduced during the slave trade have persisted in Boa Vista, resisting eradication campaigns.     

Effect of mistletoes (Amyema preissii) on host (Acacia victoriae) survival

Abstract The effect of mistletoes Amyema preissii on the survival of fast growing trees of Acacia victoriae was investigated in arid central Australia. Trees with different levels of experimentally induced mistletoe infection were monitored for 4 years. Analysis of covariance failed to reveal a treatment effect of infection on host survival. Loss of trees early in the experiment reduced the statistical power of the analysis, and variable infection success and the establishment of bird-dispersed mistletoes on experimental trees blurred the distinction between treatments. However regression analysis showed a significant relationship between the volume of mistletoe and tree mortality. The implications for the design of future experiments are discussed.     

螺旋藻乙醇酸氧化酶(GO)的研究

采用比色法对鄂尔多斯高原碱湖的钝顶螺旋藻(S1)与国外引进的钝顶螺旋藻(S2)和极大螺旋藻(S3)的乙醇酸氧化酶(GO)进行了比较研究。结果表明:在25℃、pH 8.0条件下,S1、S2和S3的GO活性分别为70.9 U/gFW、59.6 U/gFW和80.9 U/gFW;最适温度均为30℃;在0℃~35℃(30℃)范围内比较稳定;最适pH值分别为8.6、8.2和8.4;pH值稳定范围,S1为7.6~10.0、S2为8.0~9.0;S3为8.0~8.6。S1的GO对温度和pH适应范围最宽,且在低温、高温、强酸和强碱下的活性均比引进种的高。