bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidemiological characteristics of tsutsugamushi disease in Oita Prefecture, Japan: Yearly and monthly occurrences of its infections and serotypes of its causative agent, Orientia tsutsugamushi, during 1984–2005
Authors: Ogawa Masao , Ono Testuro
Published: April 2008

Using indirect immunofluorescence assay, we examined the sera of 561 patients from November 1984 to February 2005 to determine the incidence of tsutsugamushi disease (scrub typhus) in Oita Prefecture, Japan. The results obtained were positive in 384 individuals (68.4%). Municipalities where patients were presumed to have been infected with Orientia tsutsugamushi were Taketa City (41.7%), Oyama Town (13.5%), and Ogi Town (8.3%). Infections occurred most often in October, November, and December. A small number of cases occurred from January to May. The serotypes Kuroki (47.5%), Kawasaki (42.5%), and Karp (10.0%) were detected by genetic analysis of O. tsutsugamushi DNA extracted from the blood of 120 patients. The gene sequences of the Kuroki type were highly homologous to that of the Nishino strain. The gene sequences of the Kawasaki type were identical to that of the Kawasaki strain. The gene sequence of the Karp type was highly homologous to that of the JP‐2 type. To determine the distribution of vector mites, 558 wild rodents were captured and 72 010 mites attached to these rodents were collected from 1982 to 1998. Six genera and 16 species of trombiculid mites were collected. Leptotrombidium pallidum and L. scutellare, which are known to be mite vectors for tsutsugamushi disease, accounted for 20.5% and 5.9%, respectively, of all trombiculid mites collected. The geographical distribution of cases roughly coincided with the distribution of L. scutellare. In Oita Prefecture, L. scutellare is presumed to primarily transmit tsutsugamushi disease. In addition, our results also suggest that L. pallidum transmits the Karp type of the causative rickettsia in some municipalities.
Efficacy of Clostridium butyricum preparation concomitantly with Helicobacter pylori eradication therapy in relation to changes in the intestinal microbiota
Authors: Imase Kyoto , Takahashi Motomichi , Tanaka Akifumi , Tokunaga Kengo , Sugano Hajime , Tanaka Mamoru , Ishida Hitoshi , Kamiya Shigeru , Takahashi Shin'ichi
Published: April 2008

Antibiotic associated diarrhea due to human intestinal microbiota abnormalities is a side effect of H. pylori eradication therapy. We examined intestinal microbiota changes during H. pylori eradication therapy and the preventive effect of CBM588 as a probiotic agent. Nineteen patients with gastro‐duodenal ulcer were randomly divided into three groups: group A (without probiotics), group B (with regular doses of CBM588) and group C (with double doses of CBM588). The incidence of diarrhea and soft stools during H. pylori eradication therapy was 43% in group A and 14% in group B, while none of the patients in group C reported diarrhea or soft stools. Both bacterial counts and detection rates of bifidobacteria and/or obligate anaerobe were decreased by eradication therapy. However, bacterial counts of obligate anaerobes in group C were significantly higher than in group A (P < 0.05). Additionally, during eradication therapy C. difficile toxin A was detected in both group A and group B but not in group C.

In conclusion, these results indicate that H. pylori eradication therapy induces antibiotic associated diarrhea due to abnormalities in intestinal microbiota and/or C. difficile. However, these side effects might be prevented by probiotics.
Decline in a dominant invertebrate species contributes to altered carbon cycling in a low‐diversity soil ecosystem
Authors: BARRETT J. E. , VIRGINIA ROSS A. , WALL DIANA H. , ADAMS BYRON J.
Published: April 2008

Low‐diversity ecosystems cover large portions of the Earth's land surface, yet studies of climate change on ecosystem functioning typically focus on temperate ecosystems, where diversity is high and the effects of individual species on ecosystem functioning are difficult to determine. We show that a climate‐induced decline of an invertebrate species in a low‐diversity ecosystem could contribute to significant changes in carbon (C) cycling. Recent climate variability in the McMurdo Dry Valleys of Antarctica is associated with changes in hydrology, biological productivity, and community composition of terrestrial and aquatic ecosystems. One of the greatest changes documented in the dry valleys is a 65% decrease in the abundance of the dominant soil invertebrate (Scottnema lindsayae, Nematoda) between 1993 and 2005, illustrating sensitivity of biota in this ecosystem to small changes in temperature. Globally, such declines are expected to have significant influences over ecosystem processes such as C cycling. To determine the implications of this climate‐induced decline in nematode abundance on soil C cycling we followed the fate of a 13C tracer added to soils in Taylor Valley, Antarctica. Carbon assimilation by the dry valley nematode community contributed significantly to soil C cycling (2–7% of the heterotrophic C flux). Thus, the influence of a climate‐induced decline in abundance of a dominant species may have a significant effect on ecosystem functioning in a low‐diversity ecosystem.
Modeling analysis of primary controls on net ecosystem productivity of seven boreal and temperate coniferous forests across a continental transect
Authors: YUAN FENGMING , ARAIN M. ALTAF , BARR ALAN G. , BLACK T. ANDREW , BOURQUE CHARLES P.‐A. , COURSOLLE CAROLE , MARGOLIS HANK A. , McCAUGHEY J. HARRY , WOFSY STEVEN C.
Published: April 2008

Process‐based models are effective tools to synthesize and/or extrapolate measured carbon (C) exchanges from individual sites to large scales. In this study, we used a C‐ and nitrogen (N)‐cycle coupled ecosystem model named CN‐CLASS (Carbon Nitrogen‐Canadian Land Surface Scheme) to study the role of primary climatic controls and site‐specific C stocks on the net ecosystem productivity (NEP) of seven intermediate‐aged to mature coniferous forest sites across an east–west continental transect in Canada. The model was parameterized using a common set of parameters, except for two used in empirical canopy conductance–assimilation, and leaf area–sapwood relationships, and then validated using observed eddy covariance flux data. Leaf Rubisco‐N dynamics that are associated with soil–plant N cycling, and depend on canopy temperature, enabled the model to simulate site‐specific gross ecosystem productivity (GEP) reasonably well for all seven sites. Overall GEP simulations had relatively smaller differences compared with observations vs. ecosystem respiration (RE), which was the sum of many plant and soil components with larger variability and/or uncertainty associated with them. Both observed and simulated data showed that, on an annual basis, boreal forest sites were either carbon‐neutral or a weak C sink, ranging from 30 to 180 g C m−2 yr−1; while temperate forests were either a medium or strong C sink, ranging from 150 to 500 g C m−2 yr−1, depending on forest age and climatic regime. Model sensitivity tests illustrated that air temperature, among climate variables, and aboveground biomass, among major C stocks, were dominant factors impacting annual NEP. Vegetation biomass effects on annual GEP, RE and NEP showed similar patterns of variability at four boreal and three temperate forests. Air temperature showed different impacts on GEP and RE, and the response varied considerably from site to site. Higher solar radiation enhanced GEP, while precipitation differences had a minor effect. Magnitude of forest litter content and soil organic matter (SOM) affected RE. SOM also affected GEP, but only at low levels of SOM, because of low N mineralization that limited soil nutrient (N) availability. The results of this study will help to evaluate the impact of future climatic changes and/or forest C stock variations on C uptake and loss in forest ecosystems growing in diverse environments.
Long‐term impact of a stand‐replacing fire on ecosystem CO2 exchange of a ponderosa pine forest
Authors: DORE S. , KOLB T. E. , MONTES‐HELU M. , SULLIVAN B. W. , WINSLOW W. D. , HART S. C. , KAYE J. P. , KOCH G. W. , HUNGATE B. A.
Published: April 2008

Ponderosa pine (Pinus ponderosa) forests of the southwestern United States are a mosaic of stands where undisturbed forests are carbon sinks, and stands recovering from wildfires may be sources of carbon to the atmosphere for decades after the fire. However, the relative magnitude of these sinks and sources has never been directly measured in this region, limiting our understanding of the role of fire in regional and US carbon budgets. We used the eddy covariance technique to measure the CO2 exchange of two forest sites, one burned by fire in 1996, and an unburned forest. The fire was a high‐intensity stand‐replacing burn that killed all trees. Ten years after the fire, the burned site was still a source of CO2 to the atmosphere [109±6 (SEM) g C m−2 yr−1], whereas the unburned site was a sink (−164±23 g C m−2 yr−1). The fire reduced total carbon storage and shifted ecosystem carbon allocation from the forest floor and living biomass to necromass. Annual ecosystem respiration was lower at the burned site (480±5 g C m−2 yr−1) than at the unburned site (710±54 g C m−2 yr−1), but the difference in gross primary production was even larger (372±13 g C m−2 yr−1 at the burned site and 858±37 g C m−2 yr−1at the unburned site). Water availability controlled carbon flux in the warm season at both sites, and the burned site was a source of carbon in all months, even during the summer, when wet and warm conditions favored respiration more than photosynthesis. Our study shows that carbon losses following stand‐replacing fires in ponderosa pine forests can persist for decades due to slow recovery of the gross primary production. Because fire exclusion is becoming increasingly difficult in dry western forests, a large US forest carbon sink could shift to a decadal‐scale carbon source.
Long‐term ozone effects on vegetation, microbial community and methane dynamics of boreal peatland microcosms in open‐field conditions
Authors: MÖRSKY SAMI K. , HAAPALA JAANA K. , RINNAN RIIKKA , TIIVA PÄIVI , SAARNIO SANNA , SILVOLA JOUKO , HOLOPAINEN TOINI , MARTIKAINEN PERTTI J.
Published: April 2008

To study the effects of elevated ozone concentration on methane dynamics and a sedge species, Eriophorum vaginatum, we exposed peatland microcosms, isolated by coring from an oligotrophic pine fen, to double ambient ozone concentration in an open‐air ozone exposure field for four growing seasons. The field consists of eight circular plots of which four were fumigated with elevated ozone concentration and four were ambient controls. At the latter part of the first growing season (week 33, 2003), the methane emission was 159±14 mg CH4 m−2 day−1 (mean±SE) in the ozone treatment and 214±8 mg CH4 m−2 day−1 under the ambient control. However, towards the end of the experiment the ozone treatment slightly, but consistently, enhanced the methane emission. At the end of the third growing season (2005), microbial biomass (estimated by phospholipid fatty acid biomarkers) was higher in peat exposed to ozone (1975±108 nmol g−1 dw) than in peat of the control microcosms (1589±115 nmol g−1 dw). The concentrations of organic acids in peat pore water showed a similar trend. Elevated ozone did not affect the shoot length or the structure of the sedge E. vaginatum leaves but it slightly increased the total number of sedge leaves towards the end of the experiment. Our results indicate that elevated ozone concentration enhances the general growth conditions of microbes in peat by increasing their substrate availability. However, the methane production did not reflect the increase in the concentration of organic acids, probably because hydrogenotrophic methane production dominated in the peat studied. Although, we used isolated peatland microcosms with limited size as study material, we did not find experimental factors that could have hampered the basic conclusions on the effects of ozone.
Sixty years of environmental change in the world's largest freshwater lake – Lake Baikal, Siberia
Authors: HAMPTON STEPHANIE E. , IZMEST'EVA LYUBOV R. , MOORE MARIANNE V. , KATZ STEPHEN L. , DENNIS BRIAN , SILOW EUGENE A.
Published: April 2008

High‐resolution data collected over the past 60 years by a single family of Siberian scientists on Lake Baikal reveal significant warming of surface waters and long‐term changes in the basal food web of the world's largest, most ancient lake. Attaining depths over 1.6 km, Lake Baikal is the deepest and most voluminous of the world's great lakes. Increases in average water temperature (1.21 °C since 1946), chlorophyll a (300% since 1979), and an influential group of zooplankton grazers (335% increase in cladocerans since 1946) may have important implications for nutrient cycling and food web dynamics. Results from multivariate autoregressive (MAR) modeling suggest that cladocerans increased strongly in response to temperature but not to algal biomass, and cladocerans depressed some algal resources without observable fertilization effects. Changes in Lake Baikal are particularly significant as an integrated signal of long‐term regional warming, because this lake is expected to be among those most resistant to climate change due to its tremendous volume. These findings highlight the importance of accessible, long‐term monitoring data for understanding ecosystem response to large‐scale stressors such as climate change.
Effects of temperature and fertilization on nitrogen cycling and community composition of an urban lawn
Authors: BIJOOR NEETA S. , CZIMCZIK CLAUDIA I. , PATAKI DIANE E. , BILLINGS SHARON A.
Published: April 2008

We examined the influence of temperature and management practices on the nitrogen (N) cycling of turfgrass, the largest irrigated crop in the United States. We measured nitrous oxide (N2O) fluxes, and plant and soil N content and isotopic composition with a manipulative experiment of temperature and fertilizer application. Infrared lamps were used to increase surface temperature by 3.5±1.3 °C on average and control and heated plots were split into high and low fertilizer treatments. The N2O fluxes increased following fertilizer application and were also directly related to soil moisture. There was a positive effect of warming on N2O fluxes. Soils in the heated plots were enriched in nitrogen isotope ratio (δ15N) relative to control plots, consistent with greater gaseous losses of N. For all treatments, C4 plant C/N ratio was negatively correlated with plant δ15N, suggesting that low leaf N was associated with the use of isotopically depleted N sources such as mineralized organic matter. A significant and unexpected result was a large, rapid increase in the proportion of C4 plants in the heated plots relative to control plots, as measured by the carbon isotope ratio (δ13C) of total harvested aboveground biomass. The C4 plant biomass was dominated by crabgrass, a common weed in C3 fescue lawns. Our results suggest that an increase in temperature caused by climate change as well as the urban heat island effect may result in increases in N2O emissions from fertilized urban lawns. In addition, warming may exacerbate weed invasions, which may require more intensive management, e.g. herbicide application, to manage species composition.
Accentuation of phosphorus limitation in Geranium dissectum by nitrogen: an ecological genomics study
Authors: THAYER SUSAN SUMMERS , ST CLAIR SAMUEL B. , FIELD CHRISTOPHER B. , SOMERVILLE SHAUNA C.
Published: April 2008

Global climate change experiments have shown changes in productivity, phenology, species composition, and nutrient acquisition and availability; yet, the underlying mechanisms for these responses, especially in multi‐factorial experiments, are poorly understood. Altered nutrient availability is a major consequence of global change, directly due to anthropogenic nitrogen (N) deposition, and indirectly due to shifts in temperature and water availability. In the Jasper Ridge Global Change Experiment, microarrays were used to investigate the transcriptional responses of the dominant dicot, Geranium dissectum, to simulated N deposition. The transcript levels for several photosynthetic genes were elevated in plants exposed to elevated N, as has been reported previously, validating the use of microarrays under field conditions. A coordinated response of a suite of genes previously reported to be induced in response to phosphate (Pi) deficiency was observed, including genes for the glycolytic bypass pathway, which reduces ATP and Pi requirements for sugar degradation, suggesting that the plants were phosphorus (P) limited. Confirming this conclusion, foliar P levels in G. dissectum leaves were reduced to levels that are suboptimal for growth in plants grown in elevated N and elevated CO2 plots. Thus, although plants commonly produce more biomass in response to elevated N in native grasslands, this growth response may be suboptimal due to a P limitation. Foliar P levels in plants from elevated CO2 plots were also suboptimal for growth. However, genes indicative of Pi deficiency were not significantly expressed at higher levels. Transcript levels for genes involved in nitrate uptake and assimilation were unchanged by the elevated N deposition treatment, possibly due to the combined impacts of elevated N deposition and P limitation under field conditions. These observations highlight the complexity of the impact of global climate change factors in the field.
Warming increases aboveground plant biomass and C stocks in vascular‐plant‐dominated Antarctic tundra
Authors: DAY THOMAS A. , RUHLAND CHRISTOPHER T. , XIONG FUSHENG S.
Published: April 2008

We passively warmed tundra on the Antarctic Peninsula over four growing seasons and assessed its effect on dry mass and C and N stocks associated with the vascular plants Colobanthus quitensis (a cushion‐forming forb) and Deschampsia antarctica (a tussock grass), and mosses. Temperature treatments involved a warmed treatment that raised diurnal and diel canopy air temperatures by 2.3 and 1.3 °C, respectively, and a near‐ambient temperature treatment that raised diurnal and diel temperatures by 0.2 °C. These two different temperature regimes were achieved by wrapping filters around the frames to different extents and were nested within three UV treatments that filtered different solar UV wavebands. The experiment also included an ambient control treatment (unfiltered frames), and supplemental water and fertilizer treatments (applied to unfiltered frames). After four growing seasons, we collected cores of each vascular plant species and assessed the mass and C and N content of the aboveground current‐year biomass, the litter layer (which included nongreen live stems), and the organic soil horizon (which included roots). The thin nature of the organic soil horizon allowed us to sample this complete horizon and estimate near‐total ecosystem C and N stocks. A comparison of the warmed and near‐ambient temperature treatments found that warming led to greater aboveground biomass of C. quitensis, and more C in the aboveground biomass of both vascular plant species. Warming resulted in lower N concentrations of the aboveground biomass of both species. The water use efficiency of both species was greater under warming, based on their higher δ13C values. The mass of the litter layer under C. quitensis was greater under warming, and this layer contained more C and N and had a higher C : N ratio. The mass of the organic soil horizon under both species was greater under warming, and this horizon also contained more C and N. Warming also changed the species composition of the plant community – cover of C. quitensis increased while that of mosses declined. Warming resulted in the input of biomass into the system that had greater C : N ratios (and was likely more recalcitrant to decomposition) because (1) warming increased the C : N ratio of the biomass produced by both vascular plant species, (2) these inputs increased with warming because of greater biomass production, and (3) increases in C. quitensis cover led to greater biomass inputs by this species and its biomass had a greater C : N ratio than D. antarctica. Water or fertilizer supplements had few effects on aboveground biomass or C and N concentrations or pools, consistent with the relatively wet maritime climate and high soil nutrient levels of this system. Total C pools in the aboveground biomass, litter, and organic soil horizon were greater under warming. Warmed plots contained from 272 to 319 g m−2 more C than plots under near‐ambient temperatures, corresponding to a 23–34% increase in ecosystem C.
Seasonal changes in the effects of free‐air CO2 enrichment (FACE) on growth, morphology and physiology of rice root at three levels of nitrogen fertilization
Authors: YANG LIANXIN , WANG YULONG , KOBAYASHI KAZUHIKO , ZHU JIANGUO , HUANG JIANYE , YANG HONGJIE , WANG YUNXIA , DONG GUICHUN , LIU GANG , HAN YONG , SHAN YUHUA , HU JIAN , ZHOU JUAN
Published: April 2008

Over time, the relative effects of elevated [CO2] on the aboveground photosynthesis, growth and development of rice (Oryza sativa L.) are likely to be changed with increasing duration of CO2 exposure, but the resultant effects on rice belowground responses remain to be evaluated. To investigate the impacts of elevated [CO2] on seasonal changes in root growth, morphology and physiology of rice, a free‐air CO2 enrichment (FACE) experiment was performed at Wuxi, Jiangsu, China, in 2002–2003. A japonica cultivar with large panicle was exposed to two [CO2] (ambient [CO2], 370 μmol mol−1; elevated [CO2], 570 μmol mol−1) at three levels of nitrogen (N): low (LN, 15 g N m−2), medium (MN, 25 g N m−2) and high N (HN, 35 g N m−2). Elevated [CO2] increased cumulative root volume, root dry weight, adventitious root length and adventitious root number at all developmental stages by 25–71%, which was mainly associated with increased root growth rate during early growth period (EGP) and lower rate of root senescence during late growth period (LGP), while a slight inhibition of root growth rate occurred during middle growth period (MGP). For individual adventitious roots, elevated [CO2] increased average length, volume, diameter and dry weight early in the season, but the effects gradually disappeared in subsequent stages. Total surface area and active adsorption area per unit root dry weight reached their maxima 10 days earlier in FACE vs. ambient plants, but both of them together with root oxidation ability per unit root dry weight declined with elevated [CO2] during MGP and LGP, the decline being larger during MGP than LGP. The CO2‐induced decreases in specific root activities during MGP and LGP were associated with a larger amount of root accumulation during EGP and lower N concentration and higher C/N ratio in roots during MGP and LGP in FACE vs. ambient plants. The results suggest that most of the CO2‐induced increases in shoot growth of rice are similarly associated with increased root growth.
Predictive value of CASA parameters in IUI with frozen donor sperm
Authors: Freour Thomas , Jean Miguel , Mirallie Sophie , Langlois Marie‐Laure , Dubourdieu Sophie , Barriere Paul
Published: April 2008

The objective of this study was to determine if characteristics of sperm motion determined by computer‐aided semen analysis (CASA) after thawing and preparation on discontinuous gradient could predict pregnancy outcome after intrauterine insemination (IUI) from frozen donor sperm. A retrospective analysis of 100 non‐selected women undergoing 171 consecutive donor insemination cycles was conducted between January 2006 and April 2007. Semen samples from all donors were analysed after thawing and density gradient preparation. Women who became pregnant and those who did not were comparable in terms of age, ovarian stimulation regimen and indication of IUI with donor semen. Pregnancy rate per cycle was 21.8%, and pregnancy occurred after 2.5 IUI cycles on average. Motility parameters of sperm measured by CASA (VAP, VCL, VSL, LIN, STR, and ALH) and total spermatozoa concentration after preparation on discontinuous gradient showed no difference in both groups. Progressive and total motile spermatozoa concentration, as well as progressive and total motile percentages was significantly higher in pregnancy group. The receiver operating characteristic (ROC) curve analysis showed that total motile percentage >17% and motile concentration >0.9 × 106/mL best predicted pregnancy. In a multivariate analysis, only total motility percentage was able to predict pregnancy. Sperm motility parameters of frozen‐thawed prepared donor sperm obtained by CASA do not seem to predict pregnancy in IUI cycles. Total motile and progressive percentages and concentrations remain the best prognostic elements for pregnancy in IUI with donor semen.
PSP‐I/PSP‐II spermadhesin exert a decapacitation effect on highly extended boar spermatozoa
Authors: Caballero Ignacio , Vazquez Juan M. , Mayor Gloria M. , Almiñana Carmen , Calvete Juan J. , Sanz Libia , Roca Jordi , Martinez Emilio A.
Published: April 2008

PSP‐I/PSP‐II heterodimer is a major protein of boar seminal plasma that is able to preserve, in vitro, the viability, motility and mitochondrial activity of highly‐extended boar spermatozoa. However, a relationship between the protective effects of the heterodimer and sperm capacitation is still unclear. The present study investigated the effect of the PSP‐I/PSP‐II (1.5 mg/mL) on membrane stability, intracellular calcium concentration ([Ca2+]I) and plasma membrane and acrosome integrity of highly extended boar spermatozoa. Boar spermatozoa were diluted to 1 × 106 spermatozoa/mL and incubated at 38 °C in Phosphate‐buffered saline (PBS) for 10, 30, 60, 120 and 300 min or in modified Tris‐buffered medium (mTBM) for 10, 20, 30, 60 and 120 min. After each incubation time, the membrane stability (using Merocyanine‐540/Yo‐Pro‐1), elevation of [Ca2+]I (using Fluo‐3‐AM/PI) and the sperm plasma membrane and acrosome integrity (using SYBR‐14/PI/PE‐PNA) were evaluated by flow cytometry. As expected, exposure of the spermatozoa to the PSP‐I/PSP‐II preserved the plasma membrane and acrosome integrity compared to non‐exposed spermatozoa in both media PBS and mTBM (p < .01). The evaluation of membrane stability showed no differences in the percentages of viable sperm with instable plasma membrane in the presence of the PSP‐I/PSP‐II compared to controls irrespective of the dilution media. The evaluation of the [Ca2+]I levels showed that while spermatozoa incubated in mTBM and exposed to PSP‐I/PSP‐II had lower [Ca2+]I than controls (39.08% vs. 47.97%, respectively; p < .05), no differences were observed in those samples incubated in PBS. However, a temporal evaluation of the samples showed that a similar proportion of live spermatozoa were able to achieve high levels of [Ca2+]I and membrane instability independent of the presence of PSP‐I/PSP‐II. In conclusion, PSP‐I/PSP‐II exert a non‐permanent decapacitation effect on highly extended boar spermatozoa that is related with a delay in the increase of [Ca2+]I levels.
The long strange trip of Borrelia burgdorferi outer‐surface protein C
Authors: Radolf Justin D. , Caimano Melissa J.
Published: April 2008

Borrelia burgdorferi must adapt physiologically to two markedly different host milieus and efficiently transit between its mammalian host and arthropod vector during tick feeding. Differential production of lipoproteins is essential for spirochaetes to survive, multiply and migrate within both hosts. Outer‐surface protein C (OspC), which is induced during the blood meal, is critical for transmission of Lyme disease spirochaetes by nymphal ticks. Its biological function is poorly understood, however, despite the fact that its crystal structure has been solved. Evidence has accumulated that OspC blocks clearance of spirochaetes following inoculation in skin, and it is thought to do so by facilitating evasion of innate immunity. The study by Liang and co‐workers in this edition of Molecular Microbiology extends this work by showing that OspC prevents early elimination and promotes dissemination. Surprisingly, they also show that unrelated borrelial outer‐surface lipoproteins can replace these functions in an ospC mutant. They propose that an abundance of lipoprotein(s) is needed to stabilize the borrelial outer membrane against innate defences. This provocative work clearly runs counter to prevailing orthodoxies of bacterial pathogenesis. It also points the way towards future studies that will clarify the ‘partially specific’ roles of this enigmatic molecule in Lyme disease pathogenesis.
Identification of antigenic proteins from Echinostoma caproni (Trematoda) recognized by mouse immunoglobulins M, A and G using an immunoproteomic approach
Authors: SOTILLO J. , VALERO L. , SÁNCHEZ DEL PINO M. M. , FRIED B. , ESTEBAN J. G. , MARCILLA A. , TOLEDO R.
Published: April 2008

Antigenic proteins of Echinostoma caproni (Trematoda) against mouse IgM, IgA, IgG, IgG1 and IgG2a were investigated by immunoproteomics. Excretory/secretory products (ESP) of E. caproni separated by two‐dimensional (2D) gel electrophoresis were transferred to nitrocellulose membranes and probed with the different mouse immunoglobulin classes. A total of four proteins (enolase, 70 kDa heat‐shock protein (HSP‐70), actin and aldolase) were accurately identified. Enolase was recognized in eight different spots of which seven of them were detected in the expected molecular weight and were recognized by IgA, IgG or IgG and IgG1. Another spot identified as enolase at 72 kDa was only recognized by IgM. Digestion with N‐glycosidase F of the 72 kDa band rendered a polypeptide with an apparent molecular weight similar to that expected for enolase recognized by Western immunoblotting using anti‐enolase antibodies. This suggests that glycosylated forms of enolase may be involved in the early thymus‐independent responses against E. caproni. Early IgM responses were also generated by actin and the HSP‐70 which suggests that these proteins are exposed early to the host and may be of importance in the parasite establishment. The IgA responses also appear to be mediated by the HSP‐70 and aldolase which could be related with the close contact of these proteins with the host mucosal surface after secretion.
Photosynthesis in aquatic adventitious roots of the halophytic stem‐succulent Tecticornia pergranulata (formerly Halosarcia pergranulata)
Authors: RICH SARAH M. , LUDWIG MARTHA , COLMER TIMOTHY D.
Published: April 2008

In flood‐tolerant species, a common response to inundation is growth of adventitious roots into the water column. The capacity for these roots to become photosynthetically active has received scant attention. The experiments presented here show the aquatic adventitious roots of the flood‐tolerant, halophytic stem‐succulent, Tecticornia pergranulata (subfamily Salicornioideae, Chenopodiaceae) are photosynthetic and quantify for the first time the photosynthetic capacity of aquatic roots for a terrestrial species. Fluorescence microscopy was used to determine the presence of chloroplasts within cells of aquatic roots. Net O2 production by excised aquatic roots, when underwater, was measured with varying light and CO2 regimes; the apparent maximum capacity (Pmax) for underwater net photosynthesis in aquatic roots was 0.45 µmol O2 m−2 s−1. The photosynthetic potential of these roots was supported by the immunolocalization of PsbA, the major protein of photosystem II, and ribulose‐1‐5‐bisphosphate carboxylase/oxygenase (Rubisco) in root protein extracts. Chlorophyllous aquatic roots of T. pergranulata are photosynthetically active, and such activity is a previously unrecognized source of O2, and potentially carbohydrates, in flooded and submerged plants.
Altered photosynthetic electron channelling into cyclic electron flow and nitrite assimilation in a mutant of ferredoxin:NADP(H) reductase
Authors: HANKE GUY THOMAS , ENDO TSUYOSHI , SATOH FUMIHIKO , HASE TOSHIHARU
Published: April 2008

The mechanism by which plants regulate channelling of photosynthetically derived electrons into different areas of chloroplast metabolism remains obscure. Possible fates of such electrons include use in carbon assimilation, nitrogen assimilation and redox signalling pathways, or return to the plastoquinone pool through cyclic electron flow. In higher plants, these electrons are made accessible to stromal enzymes, or for cyclic electron flow, as reduced ferredoxin (Fd), or NADPH. We investigated how knockout of an Arabidopsis (Arabidopsis thaliana) ferredoxin:NADPH reductase (FNR) isoprotein and the loss of strong thylakoid binding by the remaining FNR in this mutant affected the channelling of photosynthetic electrons into NADPH‐ and Fd‐dependent metabolism. Chlorophyll fluorescence data show that these mutants have complex variation in cyclic electron flow, dependent on light conditions. Measurements of electron transport in isolated thylakoid and chloroplast systems demonstrated perturbed channelling to NADPH‐dependent carbon and Fd‐dependent nitrogen assimilating metabolism, with greater competition in the mutant. Moreover, mutants accumulate greater biomass than the wild type under low nitrate growth conditions, indicating that such altered chloroplast electron channelling has profound physiological effects. Taken together, our results demonstrate the integral role played by FNR isoform and location in the partitioning of photosynthetic reducing power.
Observations on the Macroscopic Anatomy of the Intestinal Tract and its Mesenteric Folds in the Pampas Deer (Ozotoceros bezoarticus, Linnaeus 1758)
Authors: Pérez W. , Clauss M. , Ungerfeld R.
Published: April 2008

We described the macroscopic anatomy of the intestines and their peritoneal folds of five adult pampas deer (Ozotoceros bezoarticus), a cervid species considered to ingest a high proportion of grass in its natural diet. The mean (±SD) body weight was 17 (±2) kg. The small intestine and the caecocolon measured 495 (±37) cm and 237 (±24) cm in length, respectively, with an average ratio (small intestine:caecocolon) of 1.9 (±0.1). The ascending colon had two and a half centripetal gyri, a central flexure and two centrifugal gyri. The spiral ansa, which was similar to an ellipse, was fixed to the whole left face of the mesenterium. Apart from the peritoneal folds described in the Nomina Anatomica Veterinaria, three additional, hitherto not described folds were found: a fold that fixed the caecum to the proximal ansa of the ascending colon, one that joined the terminal part of the proximal ansa to the last centrifugal gyrus of the spiral ansa of the ascending colon, and one that linked the ascending duodenum to the proximal ansa of the ascending colon. When compared with published data from other cervids of different feeding niches, it appears that, among cervids, the ratio of small intestine to the caecocolon length does not reflect the natural diet.
Gastric Submucosal Fat in Cats
Authors: Heng H. G. , Teoh W. T. , Sheikh Omar A. R.
Published: April 2008

A previous study showed that a gastric intramural radiolucent band seen on radiographs and a gastric intramural hypoattenuating layer seen on computed tomography were due to the presence of gastric submucosal fat in a cat. There is no known prevalence and distribution pattern of this gastric submucosal fat in cats. This study was carried out to determine the prevalence and distribution pattern of submucosal fat in cat stomachs. Histologic examination of 41 cat stomachs was performed after scheduled killing of cats, obtained from animal shelters. The results revealed that submucosal fat was present in all stomachs. However, thickness and distribution pattern of the submucosal fat varied.
Stereological Assessment of the Epithelial Surface Area of the Ovine Palatine and Pharyngeal Tonsils
Authors: Casteleyn C. , Cornillie P. , Simoens P. , Van Den Broeck W.
Published: April 2008

Although ovine tonsils play a major role in prion diseases, their morphology is poorly documented and morphometric data are sparse. Therefore, a stereological assessment of the surface area of the palatine and pharyngeal tonsils of five sheep was performed. The epithelial surface area of both tonsils is considerably increased by the presence of tonsillar crypts and folds. The mean epithelial surface area of the paired palatine tonsil was 7.14 cm² and that of the pharyngeal tonsil was 23.5 cm². In comparison with the paired palatine tonsil, the volume of the pharyngeal tonsil was almost two times larger, whilst its surface area was more than three times larger.
Sex Differences in Feeding Activity Results in Sexual Segregation of Feral Goats
Authors: Dunbar Robin I. M. , Shi Jianbin
Published: April 2008

Sexual segregation is common in ungulates. We show, in a high latitude population of feral goats where behavioural synchrony and fission rates have been shown to be the best explanation for segregation, that it is differences explicitly in the feeding time requirements of the two sexes (but not those for other activities) that best explains the variations in monthly frequencies of segregation. However, this effect is less marked during winter months when short day length forces the time budgets of the two sexes to converge. We argue that the various explanations for segregation can best be interpreted as separate factors in a multivariate model in which species‐ and habitat‐specific weightings influence the relative importance of these variables, and thus the likelihood that segregation will occur.
Mating Patterns of Red‐Eyed Treefrogs, Agalychnis callidryas and A. moreletii
Authors: Briggs Venetia S.
Published: April 2008

Deviations from random mating in frogs are often explained by two different size‐based patterns. The large‐male mating advantage predicts that males found in amplexus with females will be larger on average than non‐amplectant males, whereas size‐assortative mating predicts that males and females found in amplexus will maintain an optimal size ratio. Both these pairing patterns are consistent with a female mating preference for larger males, or for males of a given size relative to the choosy female. I examined pairing patterns of two species of Neotropical hylids, Agalychnis callidryas and A. moreletii for three consecutive breeding seasons in Belize, Central America to evaluate whether mating behavior was influenced by either a large‐male mating advantage or size‐assortative mating. For each species, I compared size traits between amplectant and non‐amplectant males, and within amplectant pairs, and I quantified fertilization success for each amplectant pair. For both species I found evidence of deviations from random mating by size, but the nature of the deviations varied between species and among years. The proportion of eggs fertilized was consistently high among years for both species and there was no relationship between fertilization success and the size ratio of amplectant pairs. These data are consistent with female mate preference, but a role for male–male competition cannot be excluded. My findings suggest that mating patterns may be density‐dependent and that the nature and intensity of sexual selection may be increased by extreme environmental conditions.
Multiple Mating Increases Fecundity, Fertility and Relative Clutch Mass in the Female Leopard Gecko (Eublepharis macularius)
Authors: LaDage Lara D. , Gutzke William H. N. , Simmons Richard A. , Ferkin Michael H.
Published: April 2008

Females across many taxa may mate with several males or mate more than once with the same male within one reproductive event. Although many researchers have discussed the effects of multiple mating on reproductive success of females, few studies have attempted to disentangle whether the reproductive success of females differs with respect to whether females mate with multiple males or mate more than once with one male. In this study, we hypothesized that female leopard geckos (Eublepharis macularius) increase aspects of their reproductive success, such as fecundity, fertility and relative clutch mass, by mating more than once within one reproductive event, either by mating repeatedly with the same male or multiply mating with different males. We controlled for the potentially confounding variables of mating frequency and mate number by allowing females to mate once with one male, twice with the same male, or twice with two different males. We found that females that mated with more than one male laid more clutches, exhibited increased egg fertility and invested more in clutches relative to females that mated only once with one male, whereas females that mated twice to the same male were intermediate for these variables. Thus, reproductive success is higher among female leopard geckos that mated with more than one male compared to female leopard geckos that mated only once.
Neither Mating Rate Nor Spermatophore Feeding Influences Longevity in a Ladybird Beetle
Authors: Perry Jennifer C. , Rowe Locke
Published: April 2008

Females of many species experience costs associated with mating. Seminal products, including nuptial gifts, may mitigate these mating costs or exacerbate them. For example, nuptial gifts derived from male accessory glands may transfer nutrition or potentially harmful seminal proteins to females. In this study, we assay the costs of multiple mating and the consumption of seminal products in a ladybird beetle. We compared longevity in females mated singly or multiply, while allowing or preventing spermatophore consumption at each mating. In order to distinguish a cost of mating per se from a cost of elevated reproduction, we prevented reproduction by using nutrient‐stressed females. Mating singly or multiply had no effect on female longevity, nor did spermatophore feeding influence longevity. The results imply, first, that intermediate mating rates do not directly harm females, though females may experience other indirect costs of mating (e.g. reduced foraging efficiency) or costs of reproduction; and second, that spermatophores transfer neither food nor directly harmful substances to female ladybirds.
Management of fungal root‐rot pathogens in tropicalAcacia mangiumplantations
Authors: Eyles A. , Beadle C. , Barry K. , Francis A. , Glen M. , Mohammed C.
Published: April 2008

Acacia mangiumis a fast‐growing tree species. It is mainly planted in large monocultures for pulpwood in South‐East Asia. Root rot has become the most economically damaging disease of this species with high tree mortality rates observed during second and third rotations. Two main types of root rots have been found inA.mangium, viz. brown root‐rot and red‐root disease caused byPhellinusspp. andGanodermaspp., respectively. To assess the future management options for root rot ofA.mangium, we review past and current disease‐management strategies for root rot in different temperate and tropical industrial tree crops. The efficacies of a wide range of silvicultural, chemical and biological options are detailed, and their potential utilization in managing root rot ofA.mangiumis discussed. We conclude that the current gaps in knowledge regarding identification, biology and disease epidemiology of the root‐rot pathogens will need to be addressed so that effective management options can be developed.
Distribution of ant species and mounds (Formica) in different‐aged managed spruce stands in eastern Finland
Authors: Kilpeläinen J. , Punttila P. , Finér L. , Niemelä P. , Domisch T. , Jurgensen M. F. , Neuvonen S. , Ohashi M. , Risch A. C. , Sundström L.
Published: April 2008

Mound‐building ants (Formicaspp.), as key species, have large impacts on organisms and ecosystem functions in boreal Eurasian forests. The density, sizes and locations of ant mounds determine the magnitude and the spatial distribution of ant activities in forest ecosystems. Clear‐cutting can destroy wood ant colonies, and the species, abundance, dimensions and locations of ant mounds may change as forest stand structure changes with stand age. We compared ant species composition, ant mound numbers and dimensions, and the spatial distribution of mounds in Norway spruce [Picea abies(L.) Karst.] stands of different age (5, 30, 60 and 100 years) in eastern Finland. The mound density ofFormica aquiloniaYarr. was greater in the two oldest stand age classes, while most mounds ofFormica rufaL., Formica polyctenaFörst., Formica lugubrisZett., Formica exsectaNyl. andFormica pressilabrisNyl. were found in the two youngest age classes. The mean volume, the volume per area and height/diameter ratio ofF. aquiloniamounds increased with stand age. In the oldest stand age class, mounds were slightly smaller in well‐lit locations than in shade and near stand edges than further from the edges indicating that new mounds are established in well‐lit locations. Similarly, the longest slopes of the mounds faced south, indicating the importance of exposure to the sun.F. aquiloniamounds were concentrated near stand edges, and the spatial distribution of the mounds was aggregated in some stands. At the ecosystem level, the aggregation of ant mounds near stand edges may increase the edge productivity, as mounds concentrate resources to the edges and release nutrients after abandonment.
The fate of an intentional introduction of Formica lugubris to North America from Europe
Authors: Storer A. J. , Jurgensen M. F. , Risch A. C. , Delisle J. , Hyslop M. D.
Published: April 2008

Red wood ants (Formica s.str.) are not prevalent in the forests of North America, but commonly occur in conifer and mixed conifer forests in northern Europe and Asia. In 1971, a European red wood ant species, Formica lugubris, was intentionally established in a 35‐year‐old predominantly mixed conifer plantation approximately 30 km north of QC, Canada. The purpose of its introduction was to evaluate the potential of this species as a biological control agent against conifer‐defoliating Lepidoptera species. This red wood ant introduction was monitored periodically for about 5 years after establishment, but its long‐term fate has not been reported. We visited this field site in 2005 and found that this species was well established, and we could locate some of the nests that resulted from the original release. We mapped and measured over 100 nests around the site of original release, which ranged from 5 cm in height to over 1 m. We estimated the population of introduced ants to have grown to over 8 million in the last 34 years. Significant clustering of nests suggests that these nests may be one supercolony. F. lugubris has become a dominant understory arthropod in this mixed forest, and is likely to have ecological impacts, including effects at the community and ecosystem level.