bluuebunny/crossref_metadata_2025 huggingface dataset:
Plant macrofossil evidence for the environment associated with the Riversleigh fauna
Authors: Guerin Greg R. , Hill Robert S.
Published: November 2006

Fossil plant organs from probable Oligocene nodules at the Dunsinane Site at Riversleigh, Queensland, were studied. The deposit consists of a low diversity assemblage of reproductive and vegetative organs dominated by a single taxon of Casuarinaceae. The species of Casuarinaceae has affinities with Casuarina and Allocasuarina in having more four teeth per whorl on the photosynthetic branchlets and stomata hidden in deep furrows filled with trichomes, and as such represents the earliest known record of sub-family Cryptostomae. The species is described as Cryptostomiforma quinata gen. et sp. nov. A leaf species is assigned to Alectryon (Sapindaceae) on the basis of the anatomy of abaxial cuticular features. In particular, the morphology is indistinguishable from extant A. affinis, a species currently endemic to New Guinea. Organs with possible affinities to Rubus or Capparis were examined. The assemblage is interpreted as a possible vegetation mosaic, containing both deciduous vine thickets and sclerophyllous habitats. No evidence for the presence of rainforest was found and the fossils are not consistent with extensive lowland tropical rainforest.
What determines biomass in indigenous forests? An analysis of the Knysna Forest, South Africa
Authors: Midgley J. J. , Seydack A.
Published: November 2006

We tested the widely held assumption that indigenous forests contain maximum biomass and growth rates for local resource supply. We analysed 10 years of diameter growth of trees >10 cm in diameter from 108 plots, each 0.04 ha, in the Knysna Forest, South Africa. No correlation was found between radiation index and standing mass or growth, suggesting low environmental constraints on variation in growth rates and biomass accumulation. Gross growth and mortality rates per plot were unrelated, whereas growth rates and stocking rate per plot were positively correlated. Net growth per plot was not correlated with standing stock. Mortality rates of stems are low and, therefore, residence times are long (105 years). Despite long residence times this forest is not at aboveground biomass carrying capacity, as is indicated by weak density-dependent limits to growth.
Mixed field plantation of native and exotic species in semi-arid Brazil
Authors: Duarte N. F. , Bucek E. U. , Karam D. , Sá N. , Scotti M. R. M.
Published: November 2006

An afforestation of mixed plantation was proposed to provide wood supply and minimise exploratory actions in a biological reserve. Eucalyptus plants were indicated for this purpose. This study was carried out to test the effect of volatile oils extracted from the leaves of Eucalyptus camaldulensis Dehn. and E. grandis Hill ex Maiden on the growth of Enterolobium contortisiliquum (Vell.) Morong. Under laboratory conditions, the Enterolobium plants showed tolerance to E. grandis oil, whereas E. camaldulensis oil caused loss of leaves, inhibition of height and diameter growth and a concomitant decrease in effective PSII quantum yield and the reduction of photosynthetic electron-transport chains. The field growth of E. contortisiliquum was not modified by intercropped E. grandis plants, confirming its tolerance. Inoculation with rhizobia and or mycorrhizal fungi significantly improved the height and diameter growth of these species. The results showed that E. contortisiliquum plants could be intercropped with E. grandis for reforestation and agroforestry systems.
Tillage effects on sediment enrichment, soil quality, and crop productivity in Ethiopian Highlands
Authors: Erkossa Teklu , Itanna Fisseha , Stahr Karl
Published: November 2006

The promotion and adoption of new tillage practices requires that their potential on-site, off-site, and economic effects are acceptable. Consequently, a field experiment was conducted at Caffee Doonsa (2400 m a.s.l.; 08°57′N, 39°06′E) in the Central Highlands of Ethiopia for 6 years (1998–2003) to evaluate the effects of tillage practices on sustainable productivity and quality of the soil. Four tillage methods [broad bed and furrows (BBF), green manure (GM), ridge and furrows (RF), and reduced tillage (RT)] were arranged in a randomised complete block design with 3 replications on permanent plots (22 m by 6 m). Three crops comprising durum wheat (Triticum durum Desf.), lentil (Lens culinaries Medik), and tef (Eragrostis tef), were sown in rotation. Relative crop productivity index (RPI), financial profitability, the nutrient enrichment ratio (ER) of the eroded sediment, and soil quality index (SQI) were used as performance indicators. With its highest RPI, the use of BBF significantly increased the grain yield of lentils by 59% compared with the control, and RT resulted in the highest grain yield of wheat and tef. Economically, BBF was the most profitable option for lentils with 65% increase in gross margin, whereas RT resulted in 11% and 8% increase in that of wheat and tef, respectively. The ER indicated that the nutrient and organic matter content of the eroded sediment was always greater than that of surface soil, but there were no consistent effects associated with the treatments. The SQI showed a positive trend for GM, BBF, and RT, but differences were not statistically different at P ≤ 0.05. Overall, none of the tillage treatments was superior, but we encourage use of BBF and RT because of their positive productivity and economic trends. Further research is needed to tap the potential soil quality improvements anticipated for the GM treatment. To optimise the overall benefits, a complete system has to be developed, perhaps using BBF for lentils followed by RT for wheat and tef.
Metabolic syndrome and obesity in an insect
Authors: Schilder Rudolf J. , Marden James H.
Published: November 2006

Dragonflies infected with noninvasive gregarine gut parasites (Microsporidia, Apicomplexa) have reduced flight-muscle performance, an inability to metabolize lipid in their muscles, twofold-elevated hemolymph carbohydrate concentrations, and they accumulate fat in their thorax in a manner analogous to mammalian obesity. Gregarine infection is associated with inappropriate responses of hemolymph carbohydrate concentration to insulin and with chronic activation in the flight muscles of p38 MAP kinase, a signaling molecule involved in immune and stress responses. Short-term exposure to gregarine excretory/secretory products caused elevated blood carbohydrate and p38 MAPK activation in healthy individuals. These characteristics comprise a set of symptoms and processes that are known in mammals as metabolic syndrome but which have not previously been described in other animal taxa. In addition to expanding the known taxonomic breadth of metabolic disease, these results indicate that insects may be useful experimental models for studying its underlying biology and mechanisms.
The mediator complex functions as a coactivator for GATA-1 in erythropoiesis via subunit Med1/TRAP220
Authors: Stumpf Melanie , Waskow Claudia , Krötschel Marit , van Essen Dominic , Rodriguez Patrick , Zhang Xiaoting , Guyot Boris , Roeder Robert G. , Borggrefe Tilman
Published: November 2006

The Mediator complex forms the bridge between transcriptional activators and RNA polymerase II. Mediator subunit Med1/TRAP220 is a key component of Mediator originally found to associate with nuclear hormone receptors. Med1 deficiency causes lethality at embryonic day 11.5 because of defects in heart and placenta development. Here we show that Med1-deficient 10.5 days postcoitum embryos are anemic but have normal numbers of hematopoietic progenitor cells. Med1-deficient progenitor cells have a defect in forming erythroid burst-forming units (BFU-E) and colony-forming units (CFU-E), but not in forming myeloid colonies. At the molecular level, we demonstrate that Med1 interacts physically with the erythroid master regulator GATA-1. In transcription assays, Med1 deficiency leads to a defect in GATA-1-mediated transactivation. In chromatin immunoprecipitation experiments, we find Mediator components at GATA-1-occupied enhancer sites. Thus, we conclude that Mediator subunit Med1 acts as a pivotal coactivator for GATA-1 in erythroid development.
Entamoeba histolyticacell movement: A central role for self-generated chemokines and chemorepellents
Authors: Zaki Mehreen , Andrew Natalie , Insall Robert H.
Published: November 2006

Entamoeba histolyticacells, the cause of amoebic dysentery, are highly motile, and this motility is an essential feature of the pathogenesis and morbidity of amoebiasis. However, the control ofE. histolyticamotility within the gut and during invasion is poorly understood. We have used an improved chemotaxis assay to identify the key extracellular signals mediatingEntamoebachemotaxis. The dominant responses we observe are caused by factors generated byE. histolyticacells themselves. Medium that has been conditioned byE. histolyticagrowth causes both chemokinesis and negative chemotaxis. The speed of random movement is more than doubled in conditioned compared with fresh medium, and cells move efficiently away from conditioned medium by negative chemotaxis. Ethanol, the product ofEntamoebaglucose metabolism, is the principal component of the chemokinetic response. The closely related but nonpathogenicEntamoeba disparshows no change in motility in response to conditioned medium implying that these responses are central toE. histolyticapathogenesis.
West Nile virus nonstructural protein NS1 inhibits complement activation by binding the regulatory protein factor H
Authors: Chung Kyung Min , Liszewski M. Kathryn , Nybakken Grant , Davis Alan E. , Townsend R. Reid , Fremont Daved H. , Atkinson John P. , Diamond Michael S.
Published: November 2006

The complement system, by virtue of its dual effector and priming functions, is a major host defense against pathogens. Flavivirus nonstructural protein (NS)-1 has been speculated to have immune evasion activity, because it is a secreted glycoprotein, binds back to cell surfaces, and accumulates to high levels in the serum of infected patients. Herein, we demonstrate an immunomodulatory function of West Nile virus NS1. Soluble and cell-surface-associated NS1 binds to and recruits the complement regulatory protein factor H, resulting in decreased complement activation in solution and attenuated deposition of C3 fragments and C5b–9 membrane attack complexes on cell surfaces. Accordingly, extracellular NS1 may function to minimize immune system targeting of West Nile virus by decreasing complement recognition of infected cells.
Anthrax pathogen evades the mammalian immune system through stealth siderophore production
Authors: Abergel Rebecca J. , Wilson Melissa K. , Arceneaux Jean E. L. , Hoette Trisha M. , Strong Roland K. , Byers B. Rowe , Raymond Kenneth N.
Published: November 2006

Systemic anthrax, caused by inhalation or ingestion of
Bacillus anthracis
spores, is characterized by rapid microbial growth stages that require iron. Tightly bound and highly regulated in a mammalian host, iron is scarce during an infection. To scavenge iron from its environment,
B. anthracis
synthesizes by independent pathways two small molecules, the siderophores bacillibactin (BB) and petrobactin (PB). Despite the great efficiency of BB at chelating iron, PB may be the only siderophore necessary to ensure full virulence of the pathogen. In the present work, we show that BB is specifically bound by siderocalin, a recently discovered innate immune protein that is part of an antibacterial iron-depletion defense. In contrast, neither PB nor its ferric complex is bound by siderocalin. Although BB incorporates the common 2,3-dihydroxybenzoyl iron-chelating subunit, PB is novel in that it incorporates the very unusual 3,4-dihydroxybenzoyl chelating subunit. This structural variation results in a large change in the shape of both the iron complex and the free siderophore that precludes siderocalin binding, a stealthy evasion of the immune system. Our results indicate that the blockade of bacterial siderophore-mediated iron acquisition by siderocalin is not restricted to enteric pathogenic organisms and may be a general defense mechanism against several different bacterial species. Significantly, to evade this innate immune response,
B. anthracis
produces PB, which plays a key role in virulence of the organism. This analysis argues for antianthrax strategies targeting siderophore synthesis and uptake.
Smoking as a determinant of the geographical pattern of cardiac events among women in an urban population
Authors: Janzon Ellis , Engström Gunnar , Hedblad BO , Berglund Göran , Janzon Lars
Published: November 2006

Background: Smoking is the major risk factor for cardiac events in younger women and is most common in groups with the least favourable socioeconomic circumstances. Objective: To assess to what extent geographical differences in the female incidence of myocardial infarction in the city of Malmö in Sweden can be accounted for by smoking and to what extent intra-urban variances of smoking are related to socioeconomic circumstances. Method: Area specific prevalences of smokers is based on a sample of 17,319 women, aged 45—73 years. A comprehensive score was used to rank the 17 residential areas in terms of socioeconomic circumstances. Incidence of myocardial infarction and death is based on official statistics 1989— 97. Results: The area-specific prevalence of female smokers, which ranged from 17.5 to 32.5%, was inversely related to the socioeconomic score in 45- to 54 and 55- to 64-year-olds, r=-0.65 (p<0.05) and -0.59 (p<0.05). No correlation was found for women above 65 years of age. The annual age-adjusted incidence of cardiac events in the residential areas, which ranged from 151 to 414 per 100,000 person years, was strongly related to the prevalence of smokers, r=0.75 (p<0.001). Conclusion: Between 50% and 60% of the intra-urban variance of the female incidence of myocardial infarction was accounted for by smoking in this urban population. The geographical pattern of smoking was strongly related to inferior socioeconomic circumstances.
Surgical Site Infection After Cardiac Surgery: A Simplified Surveillance Method
Authors: Lucet Jean-Christophe ,   Parisian Mediastinitis Study Group
Published: November 2006

We report the results of a 2-year, 7-center program of surveillance of deep sternal wound infection (DSWI) after cardiac surgery. DSWI was defined as the need for reoperation. Stratification data were abstracted from computerized files. The incidence of DSWI was 2.2% (198 of 8,816 cardiac surgery procedures). The risk factors identified were obesity, age, coronary artery bypass grafting, postoperative mechanical ventilation, and early surgical reexploration. The resource efficiency of this simplified surveillance method is discussed.
Critical assessment of quantum mechanics based energy restraints in protein crystal structure refinement
Authors: Yu Ning , Li Xue , Cui Guanglei , Hayik Seth A. , Merz Kenneth M.
Published: November 2006

A critical evaluation of the performance of X‐ray refinement protocols using various energy functions is presented using the bovine pancreatic trypsin inhibitor (BPTI) protein. The four potential energy functions we explored include: (1) fully quantum mechanical calculations; (2) one based on an incomplete molecular mechanics (MM) energy function employed in the Crystallography and NMR System (CNS) with empirical parameters developed by Engh and Huber (EH), which lacks electrostatic and attractive van der Waals terms; (3) one based on a complete MM energy function (AMBER ff99 parameter set); and (4) the same as 3, with the addition of a Generalized Born (GB) implicit solvation term. The R, R free, real space R values of the refined structures and deviations from the original experimental structure were used to assess the relative performance. It was found that at 1 Å resolution the physically based energy functions 1, 3, and 4 performed better than energy function 2, which we attribute to the better representation of key interactions, particularly electrostatics. The observed departures from the experimental structure were similar for the refinements with physically based energy functions and were smaller than the structure refined with EH. A test refinement was also performed with the reflections truncated at a high‐resolution cutoff of 2.5 Å and with random perturbations introduced into the initial coordinates, which showed that low‐resolution refinements with physically based energy functions held the structure closer to the experimental structure solved at 1 Å resolution than the EH‐based refinements.
Site‐directed mutagenesis indicates an important role of cysteines 76 and 181 in the catalysis of hydantoin racemase from Sinorhizobium meliloti
Authors: Martínez‐Rodríguez Sergio , Andújar‐Sánchez Montserrat , Neira Jose L. , Clemente‐Jiménez Josefa M. , Jara‐Pérez Vicente , Rodríguez‐Vico Felipe , Las Heras‐Vázquez Francisco J.
Published: November 2006

Hydantoin racemase enzyme plays a crucial role in the reaction cascade known as “hydantoinase process.” In conjunction with a stereoselective hydantoinase and a stereospecific carbamoylase, it allows the total conversion from D,L‐5‐monosubstituted hydantoins, with a low rate of racemization, to optically pure D‐ or L‐amino acids. Residues Cys76 and Cys181 belonging to hydantoin racemase from Sinorhizobium meliloti (SmeHyuA) have been proved to be involved in catalysis. Here, we report biophysical data of SmeHyuA Cys76 and Cys181 to alanine mutants, which point toward a two‐base mechanism for the racemization of 5‐monosubstituted hydantoins. The secondary and the tertiary structure of the mutants were not significantly affected, as shown by circular dichroism. Calorimetric and fluorescence experiments have shown that Cys76 is responsible for recognition and proton retrieval of D‐isomers, while Cys181 is responsible for L‐isomer recognition and racemization. This recognition process is further supported by measurements of protein stability followed by chemical denaturation in the presence of the corresponding compound.
Genetic variation in the marbled lungfish Protopterus aethiopicus in Lake Victoria and introduction to Lake Baringo, Kenya
Authors: Garner S. , Birt T. P. , Mlewa C. M. , Green J. M. , Seifert A. , Friesen V. L.
Published: November 2006

Marbled lungfish Protopterus aethiopicus in Lake Victoria and two nearby smaller lakes were found to have high levels of DNA sequence variation in their mitochondrial control regions (35 haplotypes in 61 fish) but no population genetic structure (ΦST= 0·00). In contrast, marbled lungfish in Lake Baringo, Kenya, appeared to be fixed for a single control region haplotype, which occurred at low frequency in the other lakes. Using FLUCTUATE software, the female effective population size in Lake Victoria during the late Pleistocene was estimated to be c. 500 000, similar to the value estimated for the present‐day population. These observations suggest that, during the late Pleistocene dry period, a large marbled lungfish population survived either in wet refugial areas within the lake basin or in surrounding areas. Marbled lungfish were reported to have been introduced into Lake Baringo 30 years ago with a founding population of only three individuals. The lack of control region variation in the Lake Baringo population is consistent with that situation.
Discus fishes: mitochondrial DNA evidence for a phylogeographic barrier in the Amazonian genus Symphysodon (Teleostei: Cichlidae)
Authors: Ready J. S. , Ferreira E. J. G. , Kullander S. O.
Published: November 2006

Genetic relationships and variation in meristic counts, body shape and colour were examined in a large sample of Symphysodon collected from several locations in floodplain habitats along the length of the Amazon River. Surprisingly, mitochondrial DNA indicates no difference between the two historically described species, Symphysodon discus and Symphysodon aequifasciatus, but shows that non‐clinal variation exists with a distinct lineage found in the western Amazon. This lineage is consistent with a colour form that is distinct from other Symphysodon lineages. This form has a parapatric distribution and is recognized as a distinct species, Symphysodon tarzoo. Adaptation to floodwater habitats supports genetic cohesion across a large range preventing fine scale regional diversification of the genus. Possible explanations for the unusual set of distributions for genetic and colour characters relate to the history of the Amazon basin and the probable division of lowland species when submerged geologic arches influence surface topology.
Decorated Dislocations in Magnesia Crystals
Authors: PULLIAM GEORGE R.
Published: November 2006

Diffusion of iron ions into magnesia single crystals at 1350° C in a moist atmosphere produces a host lattice of magnesiowüstite. Spinel dissolved in the lattice at this temperature precipitates on dislocations during cooling. The precipitates are large enough to be viewed with a transmission microscope. Reheat treatment of the crystals containing decorated dislocations in atmospheres of CO2‐H2 results in rather gross dendritic voids through the reduction of the ferric ion. Chemically induced vacancies were found to result in the formation of helical and prismatic loop dislocation arrangements typical of vacancy condensation mechanisms. The spacing of rows of prismatic loops was found to be in agreement with the values predicted by the equations of Bullough and Newman if one assumes a critical shear value of 5(10)−6μ for magnesiowüstite at 1350°C.
Effect of Fe4+ in the System SrFeO3‐SrTiO3
Authors: CLEVENGER THOMAS R.
Published: November 2006

Perovskites of the system SrFeO3‐SrTiO3 were prepared, and measurements were made of their magnetic and electrical behavior. Chemical analysis showed that the percentage of Fe4+ varied from 72.5% for SrFeO2.86 to about zero for Sr(Fe0.1Ti0.9)O2.95; the remainder of the iron was in the Fe3+ state and electrical balance was achieved by oxygen loss. Sr(Fe1‐xTix)O3 was antiferromagnetic between x= 0 and x= 0.9, with a Néel temperature below 60°K. A parasitic ferromagnetic component developed when these compounds were cooled in a magnetic field, the magnitude of this component being dependent on the cooling field. The conductivity of these perovskites ranged from 10−8 ohm−1 cm−1 for x= 1.0 to 10−2 for x= 0.0 and showed a marked change at x= 0.8. The break corresponded to a change in slope of the lattice parameter and the disappearance of Fe4+. The Fe4+ content depended on the heat treatment and atmosphere during formation.
Density and Permeability of Sintered Slip‐Cast Magnesia
Authors: WHITEWAY S. G.
Published: November 2006

Fused magnesia was ball‐milled in ethanol for 14, 30, 48, and 100 hours, and particle‐size distributions were determined. Specimens were slip‐cast from the suspensions and were fired in air at 1300°, 1400°, and 1470°C, for times up to 8 hours, and gas‐permeability and bulk density determinations were performed on the fired pieces. For all specimens the gas flow was essentially of the Knudsen type. The maximum bulk density, 96.7% of theoretical, was obtained by sintering a specimen, cast from the magnesia ball‐milled for 100 hours, at 1470° for 3 hours. At this density the permeability was zero. The relation between permeability and porosity could be represented by the equation KM= 6.9 ° 10−10(PF)2.54, where PF is 100(d0 ‐ d/do). Here d is the bulk density and d0 is a constant representing the bulk density at which the permeability becomes zero. The foregoing equation fits the data for all specimens if it is assumed that do is a function of the particle‐size distribution in the slip, varying from 3.36 g per cm3 for the magnesia ball‐milled for 100 hours to 3.58 g per cm3 for the magnesia ball‐milled for 14 hours.
Putative lipoproteins identified by bioinformatic genome analysis of Leifsonia xyli ssp. xyli, the causative agent of sugarcane ratoon stunting disease
Authors: SUTCLIFFE IAIN C. , HUTCHINGS MATTHEW I.
Published: November 2006

Leifsonia xyli ssp. xyli is the causative agent of ratoon stunting disease, a major cause of economic loss in sugarcane crops. Understanding of the biology of this pathogen has been hampered by its fastidious growth characteristics in vitro. However, the recent release of a genome sequence for this organism has allowed significant novel insights. Further to this, we have performed a bioinformatic analysis of the lipoproteins encoded in the L. xyli genome. These analyses suggest that lipoproteins represent c. 2.0% of the L. xyli predicted proteome. Functional analyses suggest that lipoproteins make an important contribution to the physiology of the pathogen and may influence its ability to cause disease in planta.
Clinical and molecular analysis of haemoglobin H disease in Sardinia: haematological, obstetric and cardiac aspects in patients with different genotypes
Authors: Origa R. , Sollaino M. C. , Giagu N. , Barella S. , Campus S. , Mandas C. , Bina P. , Perseu L. , Galanello R.
Published: November 2006

In this study, 251 Sardinian patients (187 adults and 64 children) with haemoglobin (Hb) H disease were evaluated. Two‐hundred and sixteen patients (86%) had the deletional type (‐ ‐/‐α) and 36 (14%) patients had the non‐deletional type (‐ ‐/αNDα). A clear genotype–phenotype correlation was found, with the non‐deletional type more severe than the deletional type. Diagnosis of Hb H disease was incidental in about 60% of cases. Aplastic crises due to B19 parvovirus infection were found in five patients (2·1%), while 23 patients (9·6%) experienced one or more haemolytic crises. Nineteen patients with Hb H received sporadic red blood cell transfusions and three patients were repeatedly transfused. Forty‐seven of 61 married women (77%) had 82 pregnancies. In children, mean serum ferritin was 87 ±92 μg/l and in adults, was 192 ± 180 μg/l in females and 363 ± 303 μg/l in males. For the 98 male patients, a significant correlation was found between ferritin values and age (r2 = 0·33, P < 0·0001). In the Sardinian population, Hb H disease needs regular monitoring for early detection and treatment of possible complications, such as worsening of anaemia that may require red cell transfusion, cholelithiasis and iron overload.
Chronic inflammation: importance of NOD2 and NALP3 in interleukin-1β generation
Authors: Ferrero-Miliani L , Nielsen O H , Andersen P S , Girardin S E
Published: November 2006

Inflammation is part of the non-specific immune response that occurs in reaction to any type of bodily injury. In some disorders, the inflammatory process − which under normal conditions is self-limiting − becomes continuous and chronic inflammatory diseases might develop subsequently. Pattern recognition molecules (PRMs) represent a diverse collection of molecules responsible for sensing danger signals, and together with other immune components they are involved in the first line of defence. NALP3 and NOD2, which belong to a cytosolic subgroup of PRMs, dubbed Nod-like-receptors (NLRs), have been associated recently with inflammatory diseases, specifically Crohn's disease and Blau syndrome (NOD2) and familial cold autoinflammatory syndrome, Muckle–Wells syndrome and chronic infantile neurological cutaneous and articular syndrome (NALP3). The exact effects of the defective proteins are not fully understood, but activation of nuclear factor (NF)-κB, transcription, production and secretion of interleukin (IL)-1β and activation of the inflammasome are some of the processes that might hold clues, and the present review will provide a thorough update in this area.
Elevated levels of soluble non-classical major histocompatibility class I molecule human leucocyte antigen (HLA)-G in the blood of HIV-infected patients with or without visceral leishmaniasis
Authors: Donaghy L , Gros F , Amiot L , Mary C , Maillard A , Guiguen C , Gangneux J-P
Published: November 2006

The non-classical class I major histocompatibility complex molecules human leucocyte antigen (HLA)-G have been shown to play a role in HIV persistence, but no data are available on the expression of the soluble forms HLA-G5 and sHLA-G1 in HIV-infected patients with and without opportunistic infections. The soluble HLA-G isoform was measured with an enzyme-linked immunosorbent assay (ELISA) method in plasma from 94 subjects: 31 HIV-1-seropositive, 17 with visceral leishmaniasis (VL), seven with both VL and HIV-1 infection and 39 healthy HIV-seronegative subjects. Between groups, the frequency of sHLA-G positivity was statistically different: 81% of HIV-infected patients were positive, as were 57% of HIV–Leishmania infantum co-infected patients, 35% of HIV-seronegative patients with VL and 3% of healthy controls. Levels of the soluble forms of the immunomodulatory molecules HLA-G are elevated during HIV infection. In HIV–Leishmania co-infected patients, sHLA-G secretion could contribute to the tolerogenic environment and to Leishmania immune evasion.
Colposcopic management of high‐grade referral smears: a retrospective audit supporting ‘see and treat'?
Authors: Errington C. A. , Roberts M. , Tindle P. , Michael E. , Bulmer J. N. , Wadehra V.
Published: November 2006

Objective:  The National Health Service Cervical Screening Programme monitors the quality of colposcopy services through the annual KC65 returns. The 2002 returns demonstrated that Standard 7c, which specifies a biopsy rate ≥90% at first colposcopy visit for high‐grade referrals, was not met in the assessed 3‐month period. This was investigated along with the other standards.

Methods:  Retrospective colposcopy records were accessed for the 597 new referrals, excluding 10 pregnant patients, seen at the colposcopy clinic at the Royal Victoria Infirmary between 1 July 2001 and 31 December 2002, following an abnormal high‐grade smear. Cytology and histopathology computer records were checked for confirmation. The results were assessed against the colposcopy standards applicable at that time and the revised standards (2004).

Results:  Biopsies were taken from 94.47% (Standard ≥90%) of women at index colposcopy visit including wire loop excision biopsies from 66.16% (87.97% of high‐grade colposcopic appearances). Cervical intraepithelial neoplasia (CIN) on histology was found in 91.79% in the study group (Standard ≥85%) and in 96.71% of index visit biopsies (Standard ≥90%), meeting the applicable colposcopy standards. The revised 2004 standards specify a biopsy in ≥95% of high‐grade referrals and excision biopsies in 95% if colposcopic appearances are also high‐grade, if colposcopy is low grade but the smear is severely dyskaryotic, or when the lesion extends into the canal. The positive predictive value of high‐grade cytology for this entire group was 75.54% with CIN present in 90.95%.

Conclusion:  From this study it appears that high‐grade cytology in this centre reliably indicates high‐grade CIN. Therefore, in women referred for colposcopy following a high‐grade smear, excision biopsies should be performed in a higher proportion at the first visit to comply with the revised standards.
Hosts and symptoms of Plum pox virus: woody species other than fruit and ornamental species of Prunus
Authors: Polák J.
Published: November 2006

The presence of Plum pox virus (PPV) in woody hosts other than in fruit and ornamental Prunus species was evaluated. PPV symptoms, and their variability and intensity, are described in leaves and fruits of Prunus cerasifera, Prunus spinosa, Ligustrum vulgare and Euonymus europaea. Juglans regia is not confirmed as a new host of PPV.
Hosts and symptoms of Plum pox virus: Herbaceous hosts
Authors: Llácer G.
Published: November 2006

Plum pox virus (PPV) is polyphagous and epidemic. Apart from cultivated and wild Prunus species, a large number of herbaceous plants can be hosts of the virus. New herbaceous host species are continuously being reported following artificial inoculation studies. Some of these herbaceous hosts, Chenopodium foetidum, Nicotiana clevelandii, N. benthamiana and Pisum sativum are very useful for concentrating and purifying the virus. The list of plants that have been found to be infected with PPV in their natural environment is shorter than the list of plants which can be experimentally infected. The role of weed species in PPV survival and spread in orchards is poorly understood. It is widely accepted that annual plants or weeds are not important in the epidemiology of PPV.
Detection and characterization of Plum pox virus: serological methods
Authors: Cambra M. , Boscia D. , Myrta A. , Palkovics L. , Navrátil M. , Barba M. , Gorris M. T. , Capote N.
Published: November 2006

Tremendous progress has been made in the research and development of Plum pox virus (PPV) serological reagents and methods in recent years. Two facts have revolutionised the serological detection and characterization of the virus: the development of the ELISA method in 1977, and the later emergence of specific monoclonal antibody technology. The availability of commercial kits has popularised PPV diagnosis, now making diagnosis possible at large scale for quarantine purposes, eradication programmes and control of the disease in nurseries. The use of the universal monoclonal antibody 5B‐IVIA, used in DASI‐ELISA, is the most accurate system for routine PPV detection. Likewise, the use of typing monoclonal antibodies gives exact characterization of the main PPV types described: 4DG5 for PPV‐D, AL for PPV‐M, EA24 for PPV‐EA, and TUV and AC for PPV‐C. There is, in general, an excellent correlation between serological data obtained with PPV specific monoclonal antibodies and data obtained by molecular PCR based methods. ELISA using a single or a mixture of monoclonal antibodies will remain the preferred method for universal detection and routine screening of PPV for years to come. Today, other serological methods and reagents are also recommended in the EPPO Diagnostic Protocol, increasing the number of reliable tests available for PPV detection. These developments have helped to control sharka disease in recent years. International co‐operation in this field has been crucial to the improvement and validation of serological tools for PPV detection and characterization.
Epidemiology of sharka disease in Spain
Authors: Cambra M. , Capote N. , Cambra M. A. , Llácer G. , Botella P. , López‐Quílez A.
Published: November 2006

PPV was first detected in Spain in 1984 in Japanese plum (Prunus salicinaLindl) cv. Red Beaut and spread very quickly to other Japanese and European plums and apricot cultivars but left peach cultivars unaffected. In the years following the detection of PPV, the predominant aphid species visitingPrunusorchards in Mediterranean areas wereAphis gossypiifollowed byAphis spiraecola, the latter being the main aphid species found at present. Both species are considered to be the main vectors of PPV in Spanish earlyPrunusgrowing areas. Spatial analysis of the spread of PPV‐D in Japanese plum and apricot trees confirmed the lack of significant association between immediately adjacent trees. The observed spatial pattern of sharka suggests a lack of movement of PPV‐viruliferous aphid vectors to immediately adjacent trees and indicates their preferential movement to trees several tree spaces away. PPV‐D is the only type currently present in Spain, with the exception of a PPV‐M outbreak that was detected in and successfully eradicated from Aragón in 2002. The short‐distance spread of PPV‐M infection occurred as far as 12 m along the rows of peach trees. However, PPV‐D has not been observed to spread through peach cultivars, despite being grown in the vicinity of heavily infected plots of apricot or Japanese plum trees.
The question of seed transmissibility of Plum pox virus
Authors: Pasquini G. , Barba M.
Published: November 2006

For many years, Plum pox virus (PPV) was considered to be transmissible by seed, increasing the fear of long‐distance spread of the disease. In the late 1970s, it was claimed on the basis of biological transmission of the virus to herbaceous indicator plants and the development of serological diagnosis based on polyclonal antibodies, that PPV was seed‐transmitted, with a different infection rate according to the plant species and part of the seed which was tested. In the 1990s, PPV was characterized into four different types, and specific monoclonal antibodies were produced for them. These new and more sensitive diagnostic techniques, together with RT‐PCR with different sets of specific primers, were used to approach once again the problem of PPV transmission through seeds. The virus was detected in seed coats and cotyledons, but embryonic tissue and seedlings obtained from germinated seeds never showed symptoms, and gave negative results for PPV with both ELISA and PCR assays. No PPV isolate is currently recognized to be seed transmitted, so vertical transmission of PPV from infected mother plants to their progeny does not occur. Hypothetically, the only possibility of seed transmission would arise from a mutation in the helper component of the virus, associated with high susceptibility of the infected Prunus cultivar.
Unravelling the Prunus/Plum pox virus interactions
Authors: Decroocq V. , Ion L. , Lansac M. , Eyquard J‐P. , Schurdi‐Levraud V.
Published: November 2006

Plum pox virus (PPV) belongs to the genus Potyvirus that contains the largest number of virus species infecting plants. Its virus genome has been extensively characterised and sequenced. However, few data are available on its interactions with woody host plants. We therefore focused, in the past 4 years, both on the cellular and molecular aspects of the compatible and incompatible Prunus/PPV interactions. GFP (Green fluorescent protein)‐tagged PPV and in situ hybridisation were used to compare the localization of viral particles in stems and leaves of susceptible and resistant apricot cultivars. In parallel, molecular tools were developed through the cloning and characterization of polymorphic, homologous resistance genes and of candidate genes involved in the expression of Prunus/PPV interactions. Candidate genes are currently used to target genomic regions involved in resistance or susceptibility and to identify molecular markers indispensable for further marker assisted selection for resistance to sharka disease.
Phytophthora kernoviae on ornamentals in the UK1
Authors: Beales P. A. , Lane C. R. , Barton V. C. , Giltrap P. M.
Published: November 2006

The newly described Phytophthora kernoviae (previously known as P. taxon C) was first found in the UK in October 2003 and has been subject to emergency European Community phytosanitary legislation since 2004. Since the first finding, P. kernoviae has been found on a limited number of shrub hosts in the UK. The majority of observations have been on Rhododendron ponticum where both leaves and stems may be affected. Symptoms range from slight necrosis of leaf tips through to extensive leaf lesions, stem cankers, defoliation and apparent death of the bush. Diagnosis of P. kernoviae begins in the field with the use of generic lateral flow test kits and is completed in the laboratory using cultural and molecular techniques. To date, the organism has been detected at 29 UK sites, mainly in the South West of England. DNA profiling has shown that isolates are related with no distinct groups or clusters based on host, geographical distribution or place of origin.
Insights into Phytophthora ramorum sporulation: epidemiological and evolutionary implications1
Authors: Moralejo E. , Muñoz J. A. García , Descals E.
Published: November 2006

Two aspects on the epidemiology of Phytophthora ramorum are discussed. Firstly, in order to elucidate its spatial scale of dispersal, its modes of asexual sporulation in culture and in planta are examined and compared to those of the also aerially dispersed P. infestans. On agar media, P. ramorum sporangia are slightly sticky, tend to aggregate in clusters, and are not shed into the air even when violently shaken or subjected to strong air humidity changes. After inoculating the underside of leaves from an assortment of Mediterranean woody species, no evidence of any adaptations for wind dispersal was observed. On some hosts, it formed sporangiomata (clusters of sporangia) on the upperside. Our observations agree with previous field research in that P. ramorum is rain‐splash rather than wind dispersed, as opposed to P. infestans. Secondly, in Petri dish cultures both species sporulate heavily. However, a steep reduction in sporangial density (sporangia cm−2) was found on leaves of susceptible Mediterranean species for P. ramorum and a progressive one for P. infestans when this was inoculated on leaves of susceptible potato and other members of the Solanaceae. Furthermore, there was a negative correlation between sporangial density and virulence. We propose a similar pattern of a trade‐off between spore production and virulence to that observed by Thrall & Burdon (2003) for the Linum‐Melampsora plant‐pathogen system. Epidemiological and evolutionary implications are discussed.
Preoperative and intraoperative diagnosis of low‐grade adenosquamous carcinoma of the breast: potential diagnostic pitfalls
Authors: Ho B C‐S , Tan H W , Lee V K‐M , Tan P H
Published: November 2006

Aims Low‐grade adenosquamous carcinoma (LGAC), a rare variant of metaplastic breast cancer, may mimic benign or other low‐grade malignant lesions histologically. Diagnostic difficulty may be encountered when evaluating breast cytology, core needle biopsy or intraoperative frozen section specimens.

Methods and results Pathology reports, cytology aspirates and histological slides of LGAC diagnosed at the Department of Pathology, Singapore General Hospital, were reviewed. Four cases of LGAC were analysed. Cytology from the first case showed atypical cells and the subsequent surgical excision specimen showed a complex sclerosing lesion with LGAC. The second and third cases were investigated by core needle biopsies: the preoperative histological features were suggestive of but not diagnostic of LGAC, until further excision biopsies were performed. The fourth case entailed a frozen section specimen, for which definitive diagnosis was deferred to paraffins. The patients remained well with no evidence of recurrent disease to date.

Conclusions When limited material, in the form of needle aspirates, core biopsy specimens or frozen sections, is submitted for histology, making a diagnosis of LGAC is not only challenging, but may be impossible. In difficult cases, careful pathological assessment, clinicopathological correlation and follow‐up or complete excision biopsy may prove invaluable in establishing a definitive diagnosis.
Versican but not decorin accumulation is related to metastatic potential and neovascularization in testicular germ cell tumours
Authors: Labropoulou V T , Theocharis A D , Ravazoula P , Perimenis P , Hjerpe A , Karamanos N K , Kalofonos H P
Published: November 2006

Aims:  To investigate the expression of versican and decorin in patients with testicular germ cell tumours (GCTs) and to correlate this with the clinicopathological findings. Matrix proteoglycans versican and decorin are frequently overexpressed in various malignancies and are involved in the progression of cancer.

Methods and results:  Overexpression of versican and decorin was detected in GCTs by immunoblotting. Immunohistochemical staining for proteoglycans was performed on 71 cases of paraffin‐embedded tissues. In most of the cases increased decorin and versican stromal staining was demonstrated. In both seminomas and non‐seminomatous germ cell tumours (NSGCTs) strong staining of decorin was not found to be related to any of the clinicopathological variables. Accumulation of versican was found to be associated with vascular and lymphatic invasion, nodal metastasis and disease stage in seminomas and NSGCTs and, in addition, with tumour size and distant metastasis only in NSGCTs. Additionally, only the deposition of versican was linearly correlated with the number of microvessels in the tumour stroma in GCTs.

Conclusions:  Ectopic versican and decorin expression is a frequent feature in GCTs. Versican but not decorin accumulation in GCTs is related to metastatic potential and neovascularization and might be a useful marker for testicular malignancy.
Endogenous testosterone levels and smoking in men. The fifth Tromsø study
Authors: Svartberg Johan , Jorde Rolf
Published: November 2006

Smoking is a risk factor of coronary heart disease (CHD), while the role of testosterone in the development of CHD is controversial. The reported effects of cigarette smoking on testosterone levels in men are conflicting, and smoking may be an important confounding factor when evaluating the relationship between testosterone levels and CHD. Thus, the objective of the present study was to examine the associations of smoking status and number of cigarettes smoked per day with total and free testosterone levels in a cross‐sectional population‐based study of 3427 men participating in the fifth Tromsø study. Total testosterone, luteinizing hormone, follicle‐stimulating hormone and sex hormone‐binding globulin levels were measured with immunoassay while free testosterone levels were calculated. Waist circumference was also measured and two standardized questionnaires were completed, including smoking status and number of cigarettes smoked. The data were analysed with analysis of variance and covariance and multiple regression analysis. Smoking men had significantly higher levels of total and free testosterone compared with men who never smoked (p < 0.001 and <0.01 respectively). Both total and free testosterone levels increased significantly with increasing number of cigarettes smoked daily (p < 0.001). Smoking men had 15% higher total and 13% higher free testosterone levels compared with men who never smoked. Thus, smoking seems to be an important confounding factor when evaluating testosterone levels, and could possibly mask borderline hypogonadism.
Coryneform bacteria in semen of chronic prostatitis patients
Authors: Türk Silver , Korrovits Paul , Punab Margus , Mändar Reet
Published: November 2006

Our aim was to compare the presence and species composition of coryneform bacteria in chronic prostatitis patients and controls. Semen of 50 men with inflammatory prostatitis and 59 controls (without pelvic pain/discomfort complaints and leukocytospermia) was investigated. First‐catch urine was additionally investigated in 36 men (30 with and 6 without prostatitis). Coryneform bacteria were found in semen of 76% men with inflammatory prostatitis and 83% controls. More than half of the isolates were identified as Corynebacterium seminale. Prostatitis patients with severe leukocytospermia (>1 million white blood cells per ml) harboured significantly more Corynebacterium group G (33% vs. 2%, p = 0.0003) and Arthrobacter sp. (17% vs. 2%, p = 0.03) in comparison with controls. Nine species of coryneforms with high concentration (≥10 000 CFU per ml) were found in prostatitis patients as against only four species in controls. Half of the men harboured corynebacteria in semen as well as in urine, 22% of men in semen only, and 3% in urine only. The total concentration of coryneforms was greater in semen than in urine (median 5000 vs. 100 CFU per ml, p = 0.053). We suggest that although coryneforms are generally considered as saprophytes, they are not uniform and some species (Corynebacterium group G and Arthrobacter sp.) may be associated with inflammatory prostatitis.