bluuebunny/crossref_metadata_2025 huggingface dataset:
Forced depression of leaf hydraulic conductance in situ: effects on the leaf gas exchange of forest trees
Authors: BRODRIBB T. J. , HOLBROOK N. M.
Published: June 2007

Recent work on the hydraulic conductance of leaves suggests that maximum photosynthetic performance of a leaf is defined largely by its plumbing. Pursuing this idea, we tested how the diurnal course of gas exchange of trees in a dry tropical forest was affected by artificially depressing the hydraulic conductance of leaves (Kleaf).

Individual leaves from four tropical tree species were exposed to a brief episode of forced evaporation by blowing warm air over leaves in situ. Despite humid soil and atmospheric conditions, this caused leaf water potential (Ψleaf) to fall sufficiently to induce a 50–74% drop in Kleaf.

Two of the species sampled proved highly sensitive to artificially depressed Kleaf, leading to a marked and sustained decline in the instantaneous rate of CO2 uptake, stomatal conductance and transpiration. Leaves of these species showed a depression of hydraulic and photosynthetic capacity in response to the ‘blow‐dry’ treatment similar to that observed when major veins in the leaf were severed.

By contrast, the other two species sampled were relatively insensitive to Kleaf manipulation; photosynthetic rates were indistinguishable from control (untreated) leaves 4 h after treatment. These insensitive species demonstrate a linear decline of Kleaf with Ψleaf, while Kleaf in the two sensitive species falls precipitously at a critical water deficit.

We propose that a sigmoidal Kleaf vulnerability enables a high diurnal yield of CO2 at the cost of exposing leaves to the possibility of xylem cavitation. Linear Kleaf vulnerability leads to a relatively lower CO2 yield, while providing better protection against cavitation.
Attenuated Stress Response to Acute Lipopolysaccharide Challenge and Ethanol Administration in Vasopressin V1b Receptor Knockout Mice
Authors: Lolait S. J. , Stewart L. Q. , Roper J. A. , Harrison G. , Jessop D. S. , Young W. S. , O'Carroll A.‐M.
Published: June 2007

The arginine vasopressin (Avp) 1b receptor (Avpr1b) present on anterior pituitary corticotrophs is involved in the stimulation of adrenocorticotrophic hormone (ACTH) secretion, especially during times of stress. Corticotrophin‐releasing hormone (CRH) is considered the major ACTH secretagogue during acute stress whereas Avp appears to be the more dominant mediator of the hypothalamic‐pituitary‐adrenal (HPA) axis response during chronic stress situations. To investigate the role of the Avpr1b in the HPA axis response to acute stress, we measured ACTH and corticosterone (CORT) plasma levels in Avpr1b knockout (KO) mice and wild‐type controls in response to bacterial lipopolysaccharide (LPS) challenge and ethanol (EtOH) administration. Mice deficient in Avpr1b had markedly compromised plasma ACTH and CORT responses to acute (30 min) LPS, but normal ACTH and CORT response to more extended exposure (4 h) to the immune system activator. The plasma ACTH and CORT levels stimulated by intoxicating, sedative doses of EtOH (3.2 and 4 g/kg) were significantly decreased in the Avpr1b KO mice compared to wild‐type littermates. Significantly higher EtOH‐induced plasma ACTH and CORT secretion was measured in female than in male Avpr1b wild‐type mice. There were no differences in the blood alcohol levels following acute EtOH administration in Avpr1b KO or wild‐type mice of either gender. Our results clearly suggest that Avpr1b plays a significant role in the HPA axis response to acute immune stress and EtOH intoxication.
Extreme long‐distance dispersal of the lowland tropical rainforest tree Ceiba pentandra L. (Malvaceae) in Africa and the Neotropics
Authors: DICK CHRISTOPHER W. , BERMINGHAM ELDREDGE , LEMES MARISTERRA R. , GRIBEL ROGERIO
Published: June 2007

Many tropical tree species occupy continental expanses of rainforest and flank dispersal barriers such as oceans and mountains. The role of long‐distance dispersal in establishing the range of such species is poorly understood. In this study, we test vicariance hypotheses for range disjunctions in the rainforest tree Ceiba pentandra, which is naturally widespread across equatorial Africa and the Neotropics. Approximate molecular clocks were applied to nuclear ribosomal [ITS (internal transcribed spacer)] and chloroplast (psbB‐psbF) spacer DNA sampled from 12 Neotropical and five West African populations. The ITS (N = 5) and psbB‐psbF (N = 2) haplotypes exhibited few nucleotide differences, and ITS and psbB‐psbF haplotypes were shared by populations on both continents. The low levels of nucleotide divergence falsify vicariance explanations for transatlantic and cross‐Andean range disjunctions. The study shows how extreme long‐distance dispersal, via wind or marine currents, creates taxonomic similarities in the plant communities of Africa and the Neotropics.
A generalized method for transfecting root epidermis uncovers endosomal dynamics in Arabidopsis root hairs
Authors: Campanoni Prisca , Sutter Jens Uwe , Davis Craig Stewart , Littlejohn George Robert , Blatt Michael Robert
Published: June 2007

Progress in analysing the cellular functions of many structural proteins has accelerated through the use of confocal microscopy together with transient gene expression. Several methods for transient expression have been developed in the past few years, but their application has seen limited success beyond a few tractable species and tissues. We have developed a simple and efficient method to visualize fluorescent proteins in Arabidopsis root epidermis using co‐cultivation of seedlings with Agrobacterium rhizogenes. The method is equally suitable for transient gene expression in other species, including Thellungiella, and can be combined with supporting molecular and biochemical analyses. The method promises significant advantages for study of membrane dynamics, cellular development and polar growth in root hairs without interference in the development of the plant. Since the method targets specifically the root epidermis, it also offers a powerful tool to approach issues of root–rhizosphere interactions, such as ion transport and nutrient acquisition. As a proof of principle, we carried out transfections with fluorescent markers for the plasma membrane (NpPMA2–GFP, Nicotiana plumbaginifolia L. Plasma Membrane H+‐ATPase 2), the endoplasmic reticulum (YFP–HDEL), and the Golgi apparatus (sialyl transferase–GFP) to trace their distribution in growing Arabidopsis root hairs and epidermis. The results demonstrate that, in Arabidopsis root hairs, movement of the Golgi is faster than previously reported for tobacco leaf epidermal cells, consistent with the high secretory dynamics of the tip growing cell; they show a pattern to the endoplasmic reticulum within the cytoplasm that is more diffuse than found in tobacco leaf epidermis, and they confirm previous findings of a polarized distribution of the endoplasmic reticulum at the tip of growing root hairs.
Members of the plant NIMA‐related kinases are involved in organ development and vascularization in poplar, Arabidopsis and rice
Authors: Vigneault Frédéric , Lachance Denis , Cloutier Monikca , Pelletier Gervais , Levasseur Caroline , Séguin Armand
Published: June 2007

NIMA‐related kinases (Neks) are a family of serine/threonine kinases that have been linked to cell‐cycle regulation in fungi and mammals. Information regarding the function of Neks in plants is very limited. We screened the three plant species that have had their genomes sequenced in an attempt to improve our understanding of their role in plants. We retrieved seven members in Arabidopsis thaliana, nine in Populus trichocarpa and six in Oryza sativa. Phylogenetic analysis showed that plant Neks are closely related to each other and contain paralogous genes. Moreover, their chromosome distribution and their exon–intron structure revealed that the actual plant Nek family was derived from a single representative followed by large segmental duplication events. Functional expression analyses in the three species relied on RTqPCR in poplar and publicly available microarray data for Arabidopsis and rice. Although plant Neks are present in every organ analyzed, their expression profiles suggest their involvement in plant development processes. Furthermore, we showed that PNek1, a member of the poplar family, is expressed at sites of free auxin synthesis and is specifically involved during the vascularization process.
Effect of salt stress on the expression of NHX‐type ion transporters in Medicago intertexta and Melilotus indicus plants
Authors: Zahran Hamdi H. , Marín‐Manzano M. Carmen , Sánchez‐Raya A. Juan , Bedmar Eulogio J. , Venema Kees , Rodríguez‐Rosales M. Pilar
Published: June 2007

Medicago intertexta and Melilotus indicus, two wild leguminous herbs with different tolerance to salinity were investigated for NaCl‐induced changes in the expression level of some Na+ transporters. M. indicus plants grew well at NaCl concentration from 0 to 400 mM, whereas growth of M. intertexta plants was severely inhibited at NaCl concentrations higher than 100 mM. In M. intertexta, increasing NaCl in the growth media caused a strong increase in Na+ content concomitant with a decrease in K+ content in leaves and, above all, roots. In comparison, M. indicus plants cultivated in the presence of NaCl accumulated much less Na+ in leaves and roots and no differences in K+ content among plants grown in nutrient solution containing 100–400 mM NaCl were detected. The expression levels of four genes coding for NHX‐type Na+/H+ antiporters in the above two wild legumes were studied in plants cultivated under the different NaCl concentrations. Expression levels of the genes were higher in M. intertexta as compared with M. indicus plants. In M. intertexta, salt treatments increased MtNHX1, MtNHX3 and MtNHX4 transcript levels in leaves and roots. However, in M. indicus NaCl treatments only induced the expression of MtNHX1 in roots. Our data suggest that two different mechanisms, Na+ avoidance or accumulation into cellular compartments, are developed by the two wild legumes to cope with salt stress, and that expression of NHX antiporters is linked to the accumulator phenotype.
Drought stress and rehydration affect the balance between MGDG and DGDG synthesis in cowpea leaves
Authors: Torres‐Franklin Maria‐Lucia , Gigon Agnès , De Melo Dirce Fernandes , Zuily‐Fodil Yasmine , Pham‐Thi Anh‐Thu
Published: June 2007

Membranes are main targets of drought, and there is growing evidence for the involvement of membrane lipid in plant adaptation to such an environmental stress. Biosynthesis of the galactosylglycerolipids, monogalactosyl‐diacylglycerol (MGDG) and digalactosyl‐diacylglycerol (DGDG), which are the main components of chloroplast envelope and thylakoid membranes, could be important for plant tolerance to water deficit and for recovery after rehydration. In this study, galactolipid (GL) biosynthesis in cowpea (Vigna unguiculata L. Walp) leaves was analysed during drought stress and subsequent rewatering. Comparison of two cowpea cutivars, one drought tolerant and the other drought susceptible submitted to moderate drought stress, revealed patterns associated with water‐deficit tolerance: increase in DGDG leaf content, stimulation of DGDG biosynthesis in terms of 14C‐acetate incorporation and messenger accumulation corresponding to four genes coding for GL synthases (MDG1, MGD2, DGD1 and DGD2). Similar to phosphate starvation, lack of water enhanced DGDG biosynthesis and it was hypothesized that the drought‐induced DGDG accumulated in extrachloroplastic membranes, and thus contributes to plant tolerance to arid environments.
Beziehungen zwischen dem Ernährungszustand der Fichte (Picea abies Karst.), ihrem Kernfäulebefall und der Pilzhemmwirkung ihres Basts1
Authors: Von Alcubilla M. , Diaz‐Palacio M. P. , Kreutzer K. , Laatsch W. , Rehfuess K. E. , Wenzel G.
Published: June 2007

Relationships between nutrition and heart rot attack of Norway spruce (Picea abies Karst.) and the fungistatic effect of its inner bark. The fresh inner bark of Norway spruce stems and roots inhibits mycelium growth of Fomes annosus on malt agar. Nearly all fungistatic substances of the inner bark can be extracted with chloroform and acetone. The acetone‐soluble fraction, which amounts to 13–27% of bark dry matter, was analysed. Up to now 12 phenolic substances have been identified, 5 of them have proved to inhibit Fomes annosus in vitro.

Open‐air‐experiments showed, that desiccation of the root‐zone, manganese deficiency and nitrogen hypertrophy decrease the inhibitory effect of the inner bark as well as its content of fungistatic substances.

The degree of heart rot attack in older spruce stands was found to be negatively correlated with the N‐, Fe‐ and Mn‐concentrations in needles.
Distribution and hosts of Scleroderris lagerbergii in Europe and North America
Authors: Donaubauer E.
Published: June 2007

This contribution deals with the distribution of the fungus Scleroderris lagerbergii in Europe and in North America based on our present‐day knowledge. A detailed bibliography of hostplants in the genera Pinus and Picea is included.
Tolerance of Fomes annosus isolates to pine oleoresins and pinosylvins
Authors: Gibbs J. N.
Published: June 2007

Ten Fomes annosus isolates from pine and ten from non‐pine‐hosts were subjected to the volatile components of pine oleoresin and to various concentrations of pinosylvin (PS) and pinosylvin monomethyl ether (PSM). Both the volatiles and the PS and PMS significantly reduced growth rate compared with controls. However, no detectable difference existed between the two groups of F. annosus isolates in their reactions to the substances tested.
Anfälligkeit verschiedener Schwarzkiefern‐Herkünfte bei Scleroderris lagerbergii‐Befall1
Authors: Von Siepmann R.
Published: June 2007

Susceptibility of different provenances of Pinus nigra to Scleroderris lagerbergii Gr.

6 years old trees, raised from seeds, from Austria (var. austriaca), France (var. corsiana), Greece, Italy (var. calabria), Jugoslavia, Turkey (var. pallasiana = var. caramanica) were in 3 successive years infected with conidia of Scleroderris lagerbergii. No clear differences could be found in the rate of dieback among the different sources.
Nematode population growth and disease development in the pine wilting disease
Authors: Kiyohara T. , Suzuki K.
Published: June 2007

The pine wilting disease prevalent in western Japan was studied with respect to the pine wood nematode, Bursaphelenchus lignicolus, as a causal agent. The relationship between the behavior of nematode populations within pines and disease development is discussed.
Xanthomonas populi (Ridé) comb. nov. (syn. Aplanobacter populi Ridé), specificité, variabilité et absence de relations avec Erwinia cancerogena Ur.
Authors: Ridé M. , Ridé S.
Published: June 2007

Xanthomonas populi (Ridé) comb. nov. (syn. Aplanobacter populi Ridé), specificity, variability and absence of relationship with Erwinia cancerogena Ur.

Xanthomonas populi (Ridé) comb. nov. (syn. Aplanobacter populi Ridé) the cause of bacterial canker in poplar, was studied in detail. Morphological characters, a single poplar flagellum, yellow pigmentation, along with biochemical and serological properties demonstrate that Aplanobacter populi is a species of Xanthomonas Dowson.

Its pathogenicity to Populus, thermosensitivity, low tolerance of NaCl and failure to use arabinose and cellobiose, separate this organism from other species in the Xanthomonas campestris group.

Xanthomonas populi is a pathogenic entity which has no relation to Erwinia cancerogena Ur.
Xanthomonas populi subsp. salicis, cause of bacterial canker in Salix dasyclada
Authors: de Kam M.
Published: June 2007

Detailed symptoms of a bacteriosis in Salix dasyclada Wimmer, caused by X. populi subsp. salicis De Kam are described. X. populi subsp. populi (Ridé) Ridé and Ridé, the cause of bacterial canker in poplar, and X. populi subsp. salicis, cause of canker in willow, can be distinguished by means of cultural and biochemical characters.
Research on Dothichiza‐bark necrosis (Cryptodiaporthe populea) in poplar
Authors: Gremmen J.
Published: June 2007

Research on Dothichiza‐bark necrosis caused by the fungus Cryptodiaporthe populea (Succ.) Butin in the Netherlands is reviewed. Aspects of disease symptoms, the pathogen and infection, inoculation experiments and control measures are discussed.
“Top‐dying” of Norway spruce, Picea abies (L.) Karst., with special reference to Rhizosphaera kalkhoffii Bubák
Authors: Diamandis S.
Published: June 2007

The optimum conditions for growth of Rhizosphaera kalkhoffii isolated from dead needles of Norway spruce trees affected by “top‐dying” were studied. The optimum temperature for diameter growth on malt extract, diamalt and potato dextrose agar was found to be 18°C and the fungus practically ceased growth at 24°C. Growth at 0°C was better than that at 24°C. Light had no effect on diameter growth on malt extract and diamalt agar. On malt extract agar, acidity ranging from 3.7–6.8 (after autoelaving) had no significant effect on diameter growth. Abundant pleurogenous blastospores were produced rapidly on malt extract and pycnidia as the culture aged. Pycnidia were the main sporulation type on diamalt agar.
The effect of the beech bark disease on the growth and survival of beech in northern hardwoods
Authors: Mize C. W. , Lea R. V.
Published: June 2007

A risk classification for beech (Fagus grandifolia Ehrh.) based on tree characteristics before the onset of the beech bark disease indicated that the crown widths in relation to DBH of trees that died were narrower than the crowns of survivors. Quantitative information on beech trees in the central Adirondack Region of the New York State before and during the development of the beech bark disease was available which included repeated measurements (1954–1976) of fifteen tree variables on 417 beech trees. A risk classification was developed which separated the trees by diameter and condition with a high (0.6), medium (0.3), and low (0.05) relative probability of mortality. The classification should improve the ability to separate those trees that are apt to die within a short period of time From those trees which are apt to survive.
Die Wirkung wäßriger Streuextrakte verschiedener Waldbäume auf Mycelwachstum und Konidiosporenkeimung von Fomes annosus (Fr.) Cke.
Authors: Schuck Von H. J. , Lechler H. H.
Published: June 2007

The effect of water extracts of leaf and needle litter from different forest trees on the mycelial growth and the germination rate of conidia of Fomes annosus (Fr.) Cke. Litter extracts from various forest trees and stands have distinct effects on mycelial growth and germination rate of conidia of Fomes annosus. The effects depend on concentration of the extract, period of extraction and on date of collecting the litter samples.
Research on poplar canker (Xanthomonas populi subsp. populi) in the Netherlands. Part III
Authors: Gremmen J. , de Kam M.
Published: June 2007

A new inoculation method for testing the resistance of poplars to bacterial canker caused by Xanthomonas populi subsp. populi (Ridé) Ridé & Ridé is discussed. The procedure is based on a more natural infection method and involves spraying plants in spring with bacterial suspensions.
Mycelial growth and extracellular laccase activity of Fomes annosus in response to cellobiose and sodium ligninsulphonate
Authors: Kaufmann U. , Wellendorf H.
Published: June 2007

The present study is part of an investigation of growth inhibition mechanisms in Picea abies against Fomes annosus and is concerned with the induction of ectolaccase activity in Fomes annosus (3 strains) grown on cellobiose and ligninsulphonate and a 1:1 mixture of these substrates. It is shown that mycelial growth is almost independent of the substrates used. In two of the F. annosus strains laccase is induced only by the use of ligninsulphonate whereas in the third strain it seems to be constitutive produced, which means that the laccase production is independent of the substrate.
The colour of Pinus silvestris L. seed and their susceptibility to damping‐off
Authors: Grzywacz A. P. , Rosochacka Jadwiga
Published: June 2007

Scots pine seed differ widely in colour. The black ones are more resistant to infection by damping‐off fungi. No significant differences were found related ro colour of seed coat in germination energy and capacity and 1000‐seed weight. Wide quantitative and qualitative differences in fatty acids content in the seed coats depending on seed colour and physiological state (resting, germinating and infected seeds) may affect differences in resistance of infection by damping‐off fungi.
Nectria infection of beech bark in relation to infestation by Cryptococcus fagisuga Lindiger
Authors: Lonsdale D.
Published: June 2007

Wound inoculation with an isolate of Nectria coccinea produced cankers in beech bark, the size of which was related to the severity of C. fagisuga infestation. Lesions were absent in most cases following surface inoculation of bark (non wounding) with very localised but heavy infestation. Inhibition of the host's response to fungal invasion is considered to be an important part of the insect's role in producing beech bark disease.
La maladie à Brunchorstia
Authors: Morelet M.
Published: June 2007

The Brunchorstia disease. I – Taxonomy and nomenclature of the pathogen. Critical analysis of nomenclature and taxonomy of the agent of the so‐called Scleroderris canker has led to the adoption of Gremmeniella abietina (Lagerb.) Morelet (conidial stage: Brunchorstia pinea [Karst.] Höhnel) as the name for this pathogen.

We present a detailed description of the fungus based on examination of numerous samples, and a complete critical synonymy. A neotype is proposed, a new variety is described (B. pinea var. cembrae), and we place Rhabdospora pithyophila Saccardo in the genus Foveostroma Di Cosmo.

A comparative morphological and cultural study shows the differences that exist between the genus Ascocalyx Naumov and Gremmeniella Morelet the conidiogenesis of which has been reproduced for the first time in electronic microscopy.
A survey of xylan degradation by wood‐decaying bacterial isolates
Authors: Deschamps A. M. , Lebeault J. M.
Published: June 2007

A collection of bacterial strains isolated from decaying or living wood and bark samples were tested for xylan degradation and assimilation. This character was widely distributed among the isolates and new genera of xylan‐degrading bacteria were obtained.
The distribution of fungi in sound‐looking stems of Picea abies in Norway
Authors: Huse K. J.
Published: June 2007

Ascocoryne spp. occurred only in heartwood, Neobulgaria premnophila also in sapwood, both with an upward, decreasing frequency in the lower 2–5 m of the stems. Nectria fuckeliana occurred at all heights, most abundantly in the 2–5 m above stump level and only in heartwood. Several other fungi also occurred, but less frequently.
Scanning electron microscopy of Cronartium ribicola infecting Ribes leaves1
Authors: Woo J. Y. , Martin Neil E.
Published: June 2007

Scanning electron microscopy was used to aid the study of the physical relationships between n+n stage of Cronartium ribicola and its alternate host, Ribes hudsonianum var. petiolare, and to examine the morphology of certain fungus structures. Germ tubes penetrated Ribes leaves through stomates exclusively. Formation of appressoria over stomates were also observed. Intercellular leaf spaces were more than adequate to accommodate the intercellular mycelium. The intercellular hyphae and germ tubes were attached to adjacent host cell surfaces. Haustoria were found to be consistently saccate and shown to characterize the n+n stage of C. ribicola.
Aggressiveness of Ceratocystis ulmi strains and induction of resistance in Ulmus americana
Authors: Hubbes M. , Jeng R. S.
Published: June 2007

A correlation between amino acid utilization and pathogenicity among five strains of Ceratocystis ulmi (Buis.) Moreau has been observed. Conditioning inoculation with a non‐aggressive strain of C. ulmi rendered white elm seedlings resistant to further attack by an aggressive strain of the same pathogen.
Der „Schwarze Rindenschorf” der Buche, verursacht durch Ascodichaena rugosa Butin
Authors: Butin H.
Published: June 2007

The “beech bark black scab”, caused by Ascodichaena rugosa Butin. On the bark of Fagus sylvatica the appearance of the new named “beech bark black scab” is described including morphological and ecological features of the causal fungus Ascodichaena rugosa Butin.
Canker and dieback of Sorbus spp.
Authors: MacBrayne C. G.
Published: June 2007

A disease of Sorbus spp. is described in which the main symptoms are formation of cankers and extensive dieback of primary branches. A culture programme revealed that Cytospora rubescens Fr. ex Fr. (Fungi Imperfecti, Sphaeropsidales) was constantly associated with the disease and inoculation tests proved its pathogenicity.
New developments in research into the Watermark disease of White willow (Salix alba) in the Netherlands
Authors: Gremmen J. , Kam M. de
Published: June 2007

Past research on the Watermark disease of While willow is reviewed. Recent work on Erwinia salicis suggests that the organism alone cannot produce disease symptoms, but that an additional substance or factor is required before the characteristic syndrome develops.
Water relations in the leaves of poplar clones resistant and susceptible to Melampsora larici‐populina1
Authors: Siwecki R. , Przyuyl K.
Published: June 2007

The study of water relations of poplar clones resistant and susceptible to Melampsora larici‐populina Kleb. using an air tunnel and a porometer have confirmed the considerable variability of poplars in rate of transpiration and time of stomatal opening. The differences between resistant and susceptible poplar clones were rather in the functioning of stomata than in their structures and frequency.
Phyllosticta Leaf Spot of Poplar in Southern Australia
Authors: Singh S. J. , Heather W. A.
Published: June 2007

Phyllosticta sp. was associated with spotting of leaves of numerous cultivars of poplar, including Populus euphratica Oliv., at Canberra (lat. 35°S) and Kempsey (lat. 31°S) in southern Australia. At Kempsey the spots differed morphologically from those occurring in the Canberra district and in addition the necrosis was more extensive and the premature leaf shedding more pronounced at the lower latitude.
Adelges aphids and fungi causing premature defoliation of Larch
Authors: Skarmoutsos G. , Millar C.
Published: June 2007

Meria laricis invaded needles of Larix X eurolepis at the feeding sites of Adelges spp and caused pre‐mature needle fall. The position of the feeding site on the needle determined the time of their fall. Among other fungi isolated from needles attacked by aphids were Cladosporium herbarum, Lophodermitim laricinum, Aureobasidium pullulans, Stereum sp., Thyssanophora penicillioides, Botrytis cinerea and Epicoccum sp. The feeding sites on the needles, the remaining unattacked parts of the needles and the naturally senescent needles were found to be colonized by different fungi at different times.
Cylindrocladium spp. associated with various diseases of Eucalyptus in Kerala1
Authors: Sharma J. K. , Mohanan C.
Published: June 2007

During an extensive survey of nurseries and plantations spread throughout the state, six species of Cylindrocladium were found to be associated with various diseases of Eucalyptus spp. C. quinque‐septatum was the dominant species followed by C. ilicicola, C. floridanum, C. parvum, C. curvatum and C. scoparium. C. quinqueseptatum was isolated from the specimens collected throughout Kerala irrespective of host species or geographical location. However, other species had discernible spatial distribution with a narrow host range. C. floridanum and its perfect stage, Calonectria floridana, and C. curvatum are reported for the first time on Eucalyptus in India.
Bark necrosis of Acer pseudoplatanus L. in northern Britain
Authors: Gregory S. C.
Published: June 2007

Severe bark necrosis in large Acer pseudoplatanus was studied at a site in northern England. Bark death occurred late in the growing season or in the dormant season on two occasions and was preceded by a notably dry summer in both cases.

Of several fungi isolated from cankers and areas of recent bark necrosis, Nectria coccinea and Diplodina acerina were demonstrated to be capable of causing limited necrotic extension of physical wounds in healthy A. pseudoplatanus. A third sp., Phomopsis pustulata, though the most frequently isolated fungus, showed no such ability.

It is proposed that summer drought in association with a variety of weakly pathogenic fungi can induce local bark necrosis in A. pseudoplatanus.
The influence of fertilizers on the occurrence of Armillaria mellea in Scots pine plantations
Authors: Rykowski K.
Published: June 2007

The spread of Armillaria mellea inside fertilized (with NPKCaMg) and non‐fertilized roots of pine was evaluated by: growth of mycelium on extracts from roots with bark, de‐barked roots and from bark with bast, hygroscopic property, water saturation, weight loss and microscopical observations. Negative as well as positive influences of fertilizers were observed. The problems of the multi‐aspect influence of fertilizers on the development of disease are discussed.
Diplodia shoot blight and asymptomatic persistence of Diplodia pinea on or in stems of jack pine nursery seedlings
Authors: Stanosz G. R. , Smith D. R. , Leisso R.
Published: June 2007

Diplodia pinea (syn. Sphaeropsis sapinea) is known as a major cause of damage to red pine (Pinus resinosa) seedlings in nurseries. The fungus can also be a latent pathogen of red pine seedlings, persisting in the absence of gross symptoms and later proliferating under conditions that induce host stress. In the fall of 2004, three nurseries in Wisconsin were surveyed to determine the potential for the occurrence of Diplodia shoot blight on jack pine (Pinus banksiana) seedlings and the persistence of D. pinea on or in asymptomatic seedlings of this species. Incidence of shoot blight was quantified in five 1 m long segments of an interior row in each of two survey areas in each nursery. The pathogen was identified on symptomatic seedlings collected in these areas on the basis of presence of characteristic pycnidia and conidia. Five groups of 20 asymptomatic seedlings were also collected in each of the two survey areas in each nursery. A segment of the lower stem/root collar from each of these asymptomatic seedlings was surface‐disinfested and culturally assayed using tannic acid agar. The mean incidence of shoot blight (as high as 9%) and mean frequency of cultural detection from asymptomatic seedlings (as high as 20%) were greatest in proximity to red pine windbreaks which are a source of inoculum. Only D. pinea was confirmed from subsets of symptomatic and asymptomatic seedlings which were tested using mt SSU rDNA polymerase chain reaction (PCR) primers that allow differentiation of D. pinea from D. scrobiculata and other fungi in the genus Botryosphaeria and related anamorphic fungi. Jack pine seedlings inoculated with D. pinea isolates obtained from asymptomatic nursery seedlings developed shoot blight symptoms in greenhouse trials. Thus, the ability of D. pinea to damage jack pine seedlings in nurseries has been documented and the potential for virulent strains of this latent pathogen to be distributed on asymptomatic jack pine seedlings from nurseries has been confirmed.
Dyspepsia in HIV‐infected patients under highly active antiretroviral therapy
Authors: Werneck–Silva Ana Luiza , Prado Ivete Bedin
Published: June 2007

Background and Aim:  Upper gastrointestinal symptoms, mainly dyspepsia, are common adverse effects in patients under highly active antiretroviral therapy (HAART). Whether it is worthwhile to perform endoscopy early in their treatment is a matter of debate. We have done a prospective study of the prevalence and the etiology of endoscopic lesions in a large cohort of dyspeptic adult HIV‐infected patients under HAART, according to their immunological status.

Methods:  528 (334 men and 194 women, mean age 38) HIV‐infected patients under HAART with epigastric pain and/or nausea and vomiting underwent upper endoscopy. Patients were classified in two groups, according to CD4 cells counting (>200 cells/mm3 or ≤200 cells/mm3). Gastric and duodenal biopsies were taken from normal mucosa and any lesion found.

Results:  Gastric mucosa alterations were seen in 61.74% of patients (40.71% erythema, 18.38% erosion and 2.65% ulcer). Duodenum mucosa alterations were seen in 25.37% of patients, mainly erosions (19.50%) and ulcer (3.59%). There was no difference in endoscopic findings according to CD4 cell count groups. Chronic active gastritis was shown in 459 patients (86.93%). H. pylori infection was seen in 32.38%, and it was more prevalent in the group with CD4 > 200 (p < 0.01). Opportunistic infections and malignancies were seen exclusively in patients with CD4 ≤ 200.

Conclusions:  Most of the endoscopic lesions in dyspeptic HIV‐infected patients under HAART were not related to AIDS. Upper endoscopy was more helpful in dictating clinical treatment in patients with low CD4 counts (≤200) and should be done earlier in this group.
Vascular targeting agent Oxi4503 inhibits tumor growth in a colorectal liver metastases model
Authors: Malcontenti–Wilson Caterina , Chan Lisa , Nikfarjam Mehrdad , Muralidharan Vijayaragavan , Christophi Christopher
Published: June 2007

Background and Aim:  Oxi4503 is a potent vascular targeting agent belonging to the family of combretastatins. These agents produce an acute reduction in tumor blood flow leading to tumor necrosis. Despite evidence of its efficacy in certain malignancies, the effect on colorectal liver metastases remains largely unknown. This study investigates the effect of Oxi4503 on colorectal liver metastases in a murine model.

Methods:  The effect of a single dose of Oxi4503 on established tumors in a murine model of colorectal liver metastases was assessed following administration of 1–50 mg/kg Oxi4503. In addition, the effects of continuous, daily and intermittent dosing (1–5 mg/kg) on tumor necrosis and growth were studied by quantitative histological and stereological analysis. The effect of multiple dosing on long‐term survival was also assessed using the Kaplan–Meier analysis. The microvascular effects of therapy were studied by scanning electron microscopy of microvascular resin casts.

Results:  A single dose of 5 or 50 mg/kg of Oxi4503 produced significant tumor necrosis compared to the controls. Subcutaneous continuous dosing infusion with Oxi4503 at 1 mg/kg/day reduced tumor growth compared to the controls, but was associated with marked systemic toxicity. Daily administration over 21 days was associated with significant mortality. Intermittent dosing of Oxi4503 (two doses, 3 days apart) produced the greatest reduction in tumor growth with minimal toxicity and conferred a significant survival advantage. Microvascular casts demonstrated significant disruption of tumor vessels.

Conclusions:  A single dose of Oxi4503 produced significant necrosis and microvascular injury in colorectal liver metastases. Intermittent dosing with Oxi4503 produced the maximum reduction in tumor growth, minimal toxicity, and a significant improvement in survival. Oxi4503 is a potential anticancer agent. Further research into its mechanism of action and its synergistic use with other therapies is warranted.
Somatostatin and gabexate for post‐endoscopic retrograde cholangiopancreatography pancreatitis prevention: Meta‐analysis of randomized placebo‐controlled trials
Authors: Rudin Dan , Kiss Alexander , Wetz Robert V , Sottile Vincent M
Published: June 2007

Background and Aim:  Prior studies have suggested the efficacy of somatostatin and gabexate in post‐endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis prevention. We examined this notion in our study.

Methods:  An extensive literature search led to the inclusion of seven homogeneous high‐quality studies (Jadad score ≥4), involving 3130 patients. The studies were grouped according to the drug's length of administration: given as an infusion for 12 h (groups SOM1 and GAB1 for somatostatin and gabexate, respectively); given as an infusion for less then 12 h (groups SOM2 and GAB2 for somatostatin and gabexate, respectively); and given as a bolus (group SOM3 for somatostatin, none identified for gabexate). Separate meta‐analyses investigating post‐procedural pancreatitis and hyperamylasemia rates were conducted in a random effects model.

Results:  Pancreatitis analyses yielded significant risk differences for the SOM1, SOM3 and GAB1 groups. The resulting values were 7.7% (95% confidence intervals [CI][3.4 to 12.0], P < 0.0001), 8.2% (95% CI [4.4 to 12.0], P < 0.0001) and 5.2% (95% CI [1.1 to 9.4], P = 0.01), respectively. No statistically significant risk differences were observed for the SOM2 and GAB2 groups: −2.3% (95% CI [−5.2 to 0.5], P = 0.11) and −1.1% (95% CI [−3.8 to 1.6], P = 0.41), respectively. Hyperamylasemia analyses yielded significant risk differences for the SOM1 and SOM3 groups (P = 0.017 and 0.001, respectively), although not for the SOM2, GAB1 and GAB2 groups (P = 0.44, 0.49 and 0.47, respectively).

Conclusions:  Somatostatin administered as a bolus seems to be an efficacious measure of post‐ERCP pancreatitis prevention, reducing pancreatitis and hyperamylasemia rates, and being applicable to clinical practice. Further study is required before its introduction into routine care.
Influence of cytochrome P450 2C19 genetic polymorphism and dosage of rabeprazole on accuracy of proton‐pump inhibitor testing in Chinese patients with gastroesophageal reflux disease
Authors: Lee Yi‐Chia , Lin Jaw‐Town , Wang Hsiu‐Po , Chiu Han‐Mo , Wu Ming‐Shiang
Published: June 2007

Background and Aim:  To evaluate the optimal dosage of rabeprazole for proton‐pump inhibitor (PPI) testing of gastroesophageal reflux disease (GERD) and to test the influence of cytochrome P450 (CYP) 2C19 polymorphism in a population with a high prevalence of people who metabolize PPI poorly.

Methods:  In this randomized, open‐label trial, patients with symptoms suggestive of GERD were randomized to receive a 2‐week test with 20‐ or 40‐mg rabeprazole after diagnostic endoscopy. Symptom response was assessed with a four‐grade daily record; in addition, DNA from peripheral blood leukocytes was genotyped for CYP2C19 polymorphism with the polymerase chain reaction–restriction fragment length polymorphism technique.

Results:  Of the 164 patients who completed the study, 69 (42.1%) were endoscopically positive for esophagitis; the remaining 95 (57.9%) were diagnosed with endoscopy‐negative reflux disease. Based on the best cut‐off value for 50% symptom reduction, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for detecting erosive esophagitis were 68%, 70%, 66%, 72%, and 69%, respectively, for the 20‐mg regimen, and 84%, 71%, 64%, 88%, and 76%, respectively, for the 40‐mg regimen, a non‐significant difference. Regarding the genotype, 60 (39%) patients had two wild‐type alleles, 63 (40.9%) had one variant allele, and 31 (20.1%) had two variant CYP2C19 alleles. The presence of a variant allele did not alter the diagnostic efficacy of PPI testing.

Conclusions:  Both dose levels of rabeprazole proved efficacious in the diagnosis of GERD. Various measures of test accuracy were unrelated to the status of the CYP2C19 genotype.
Helicobacter pylori eradication improves gastric histology and decreases serum gastrin, pepsinogen I and pepsinogen II levels in patients with duodenal ulcer
Authors: Pimanov Sergey I , Makarenko Elena V , Voropaeva Alla V , Matveenko Maya E , Voropaev Eugen V
Published: June 2007

Background and Aim:  The aim of this study was to assess the gastric histopathology and serum gastrin‐17 and pepsinogens profiles in patients with duodenal ulcer before and after Helicobacter pylori eradication in a population with a very high prevalence of H. pylori. At the same time we assessed the role of H. pylori density on these variables.

Methods:  Eighty Caucasian patients with H. pylori–associated duodenal ulcer before treatment and 1 year after randomized eradication were studied. Among patients with unsuccessful eradication two groups were distinguished according to the data obtained after treatment: the group with negative rapid urease test and decreased bacterial density according to morphological score (partial elimination group); the group with positive rapid urease test and high bacterial density (failed eradication group).

Results:  One year after successful eradication, serum levels of gastrin‐17, pepsinogen I and pepsinogen II decreased. Similar changes of serum pepsinogen I and pepsinogen II levels were observed in patients with partial elimination of H. pylori infection. In the group with successful eradication, inflammation, activity, atrophy and number of lymphoid follicles in the antral mucosa fell. In the group with partial elimination, antral mucosa activity and H. pylori score reduced. Other morphological changes were statistically non‐significant.

Conclusion:  Patients with duodenal ulcer after successful eradication have improvement of morphological and functional characteristics of gastric mucosa.
Comparison of three different second‐line quadruple therapies including bismuth subcitrate in Turkish patients with non‐ulcer dyspepsia who failed to eradicate Helicobacter pylori with a 14‐day standard first‐line therapy
Authors: Uygun Ahmet , Ozel A Melih , Yildiz Oguzhan , Aslan Murat , Yesilova Zeki , Erdil Ahmet , Bagci Sait , Gunhan Omer
Published: June 2007

Background and Aim:  Many studies have reported poor results with standard first‐line treatment for Helicobacter pylori. Second‐line regimens that may overcome bacterial resistance can minimize side‐effects and optimize compliance. The aim of this study was to evaluate the efficacy of proton pump inhibitor (PPI) and bismuth subcitrate‐based quadruple therapy, after failure of a PPI plus clarithromycin and amoxicillin as first‐line therapy.

Methods:  Patients who failed to eradicate the infection after initial therapy were randomly separated into three groups. The first group received lansoprazole, bismuth subcitrate, metronidazole and amoxicillin (LBMA); in the second group metronidazole was replaced by tetracycline (LBTA); and the third group was given metronidazole and tetracycline in addition to same doses of lansoprazole and bismuth subcitrate (LBMT).

Results:  In the LBMA group, the eradication rate was 74.7% and was significantly related to sex, with no relationship to age. In the LBTA group the eradication rate was 81.5% with similar rates in males and females. No relation to sex or age was observed. In the LBMT group the eradication rate was 82.1% with no difference between women and men and it was not related to age, either. Eradication rates in study groups were similar (P > 0.05).

Conclusion:  A‐14‐day regimen of lansoprazole, bismuth subcitrate and antibiotic pairs, tetracycline–amoxicillin and tetracycline–metronidazole, is an effective quadruple therapy after one failed course of standard triple therapy. The evaluation of tolerability of and compliance with quadruple therapy needs further studies.
High risk of cardiogenic cerebral embolism for very elderly patients in sinus rhythm with left atrial appendage flow velocity below 50 cm/s
Authors: Watanabe Daisuke , Shizuka Kazuhiko , Iwamoto Toshihiko
Published: June 2007

Recent clinical trials have demonstrated that patients in sinus rhythm after cardioversion are still at risk of suffering from embolic events, but the precise mechanisms underlying the occurrence of cardiogenic cerebral embolism remain to be determined. All 72 patients aged 75 or over who were consecutively referred to our department between October 2003 and March 2006 were divided into three groups; these were: group 1, 17 patients in sinus rhythm after cardioversion; group 2, 18 patients without any history of atrial fibrillation; and group 3, 37 patients with chronic atrial fibrillation. Using transesophageal echocardiography, we evaluated the left atrial appendage flow velocity, left atrial appendage dimension, spontaneous echocardiographic contrast in the left atrium, and the presence of thrombus in the left atrial appendage. Left atrial appendage flow velocity was significantly lower in group 1 compared with group 2 (38.2 ± 6.1 vs 61.4 ± 7.4 cm/s, P < 0.001), but was even lower in group 3 (25.1 ± 9.8 cm/s, P < 0.001 vs group 1). Spontaneous echocardiographic contrast in the left atrium, thrombus in the left atrial appendage and cardiogenic cerebral embolism showed a close relationship with left atrial appendage flow velocity, and were more frequent when left atrial appendage flow velocity was less than 50 cm/s. Very elderly patients in long‐term maintenance of sinus rhythm with an left atrial appendage flow velocity of less than 50 cm/s would have a high risk of cardiogenic cerebral embolism.
Ultrasound parameters of bone health and related physical measurement indicators for the community‐dwelling elderly in Japan
Authors: Sun Wei , Watanabe Misuzu , Tanimoto Yoshimi , Shibutani Takahiro , Saito Masahisa , Usuda Kan , Kono Koichi
Published: June 2007

Deteriorated bone strength, which approaches osteoporosis, increases the likelihood that an elderly person will not able to live independently. However, few data are available pertaining to bone health and various physical objective indicators. The aim of the present study was to objectively assess bone health by quantitative ultrasound (QUS) and identify related physical measurement indicators among the elderly to aid the health promotion strategies in Japan. A cross‐sectional study was performed at five welfare centers for the aged in the suburban area of Takatsuki city, Japan. Subjects comprised community‐dwelling persons (134 men, 240 women) aged ≥60 years and registered at welfare centers. QUS of the right‐heel was conducted and recorded as stiffness index (SI). Physical factors including body components (fat and muscle mass), handgrip strength, daily physical activity, daily walking steps, maximum and usual walking speed and maximum bite force were examined objectively during the period May–June 2005. SI in women was lower than that in men (P < 0.01) and decreased significantly with age (P < 0.01). The SI correlated with six physical items in men and with all items in women. Multiple linear regression analysis showed that muscle mass, usual walking speed and maximum bite force were the strongest physical indicators of male SI; and muscle mass, maximum walking speed and maximum bite force were the strongest indicators of female SI. Muscle training, daily walking exercise and oral health care should be included in health promotion programs for the bone health of elderly women and men in Japan.