bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of Oryza rufipogon–Derived Resistance to Tungro Disease in Rice
Authors: Shibata Yuji , Cabunagan Rogelio C. , Cabauatan Pepito Q. , Choi Il-Ryong
Published: October 2007

Rice tungro disease (RTD) is caused by the interaction between Rice tungro spherical virus (RTSV) and Rice tungro bacilliform virus (RTBV), both of which are transmitted by green leafhoppers (GLH). In order to define the resistance against RTD in rice cv. Matatag 9 which was developed by interspecific hybridization between RTD-susceptible cv. IR64 and Oryza rufipogon, the reactions of Matatag 9 to the viruses and GLH were evaluated in comparison with RTD-susceptible and -resistant rice cultivars. The incidences of infection with RTSV and RTBV in Matatag 9 were significantly lower than those in the susceptible parent cv. IR64; however, no substantial differences in virus accumulation were observed between IR64 and Matatag 9 once infected with the viruses. Symptoms in Matatag 9 infected with RTBV and RTSV were milder than those observed in IR64. A higher level of antixenosis to GLH was observed in Matatag 9 compared with IR64. The levels of antibiosis against GLH in Matatag 9 were comparable with those in another GLH-resistant cultivar, and significantly higher than those in RTD-susceptible cultivars. Collectively, these results suggest that tolerance to tungro viruses and resistance to GLH both contribute to the apparent resistance to RTD in Matatag 9, although possible involvement of other resistance mechanisms cannot be excluded.
Use of a Multispectral Radiometer for Noninvasive Assessments of Foliar Disease Caused by Ray Blight in Pyrethrum
Authors: Pethybridge Sarah J. , Hay Frank , Esker Paul , Wilson Calum , Nutter Forrest W.
Published: October 2007

Foliar disease due to ray blight (Phoma ligulicola) in pyrethrum was quantified at three locations over 2 years in Tasmania, Australia. To obtain a range of ray blight disease intensities, replicated plots were treated with fungicides that varied in efficacy to control ray blight. Visual disease assessments and measurement of canopy reflectance were made at least once during spring (September through December). Visual assessments involved removal of flowering stems at ground level from which measurements of defoliation severity and the incidence of stems with ray blight were obtained. Reflectance of sunlight from pyrethrum canopies was measured at 485, 560, 660, 830, and 1,650 nm using a handheld multispectral radiometer. Measurements from these wavelengths also were used to calculate all possible reflectance ratios, as well as four vegetative indices. Relationships between wavelength bands, reflectance ratios, vegetative indices, and disease intensity measures were described by linear regression analyses. Several wavelength bands, ratios, and vegetative indices were significantly related in a linear fashion to visual measures of disease intensity. The most consistent relationships, with high R2 and low coefficients of variation values, varied with crop growth stage over time. The ratio 830/560 was identified as the best predictor of stem height, defoliation severity, and number of flowers produced on each stem in October. However, reflectance within the near-infrared range (830 nm) and the difference vegetative index was superior in November. The use of radiometric assessment of disease was noninvasive and provided savings in disease assessment time, which is critical where visual assessment is difficult and requires destructive sampling, as with pyrethrum.
Molecular and Symptom Analysis Reveal the Presence of New Phytoplasmas Associated with Sugarcane Grassy Shoot Disease in India
Authors: Nasare Kanchan , Yadav Amit , Singh Anil K. , Shivasharanappa K. B. , Nerkar Y. S. , Reddy V. S.
Published: October 2007

A total of 240 sugarcane (Saccharum officinarum) plants showing phenotypic symptoms of sugarcane grassy shoot (SCGS) disease were collected from three states of India, Maharashtra, Karnataka, and Uttar Pradesh. Phytoplasmas were detected in all symptomatic samples by the polymerase chain reaction (PCR) amplification of phytoplasma-specific 16S rRNA gene and 16S-23S rRNA spacer region (SR) sequences. No amplification was observed when DNA from asymptomatic plant samples was used as a template. Sixteen samples were selected on the basis of phenotypic symptoms and geographic location, and cloning and sequencing of the 16S rRNA and spacer regions were performed. Multiple sequence alignments of the 16S rRNA sequences revealed that they share very high sequence similarity with phytoplasmas of rice yellow dwarf, 16SrXI. However, the 16S-23S rRNA SR sequence analysis revealed that while the majority of phytoplasmas shared very high (>99%) sequence similarity with previously reported sugarcane phytoplasmas, two of them, namely BV2 (DQ380342) and VD7 (DQ380343), shared relatively low sequence similarity (79 and 84%, respectively). Therefore, these two phytoplasmas may be previously unreported ones that cause significant yield losses in sugarcane in India.
Influence of Flower Thrips on Fusarium Hardlock Severity
Authors: Mailhot D. J. , Marois J. J. , Wright D. L.
Published: October 2007

Cotton (Gossypium hirsutum) fiber is sometimes affected by hardlock, which is characterized by a failure of the fiber to expand outward from the boll at maturity. Because affected fiber is inaccessible to mechanical harvesters, yield loss can be considerable. Hardlock has been linked to infection by Fusarium verticillioides. The involvement of flower thrips (Frankliniella spp.), which are commonly found in cotton flowers, was explored. At 1100 h, approximately 10% of cotton flowers contained thrips that were carrying F. verticillioides. The effect of thrips and/or Fusarium in flowers and bolls was explored under greenhouse conditions. Exposing flowers to Fusarium and thrips resulted in bolls with the most severe symptoms. Exposure to either Fusarium or thrips alone resulted in more hardlock than was noted in the control group. The impact of thrips was also evaluated under field conditions. Field plots were treated with insecticides, a fungicide, both, or left untreated. Insecticides reduced thrips numbers and reduced hardlock severity. The fungicide had no impact on thrips numbers and was less effective at reducing hardlock. Combining insecticide and fungicide applications was no more effective than using insecticides alone, although it more frequently increased yield. The untreated control plots generally had the most severe hardlock and lowest yields. Reducing hardlock severity resulted in higher yields, although not consistently. These studies suggest that thrips increase the severity of hardlock, and reducing their numbers may diminish hardlock severity.
International Fungicide Efficacy Trials for the Management of Soybean Rust
Authors: Miles M. R. , Levy C. , Morel W. , Mueller T. , Steinlage T. , van Rij N. , Frederick R. D. , Hartman G. L.
Published: October 2007

The efficacy of fungicides in managing soybean rust was evaluated in 12 environments in South America and southern Africa over three growing seasons from 2002 to 2005. There were differences in final soybean rust severity, defoliation, and yield among the treatments at most locations. In locations where soybean rust was not severe, all the fungicides evaluated reduced severity. In locations where soybean rust was severe, applications of triazole and triazole + strobilurin fungicides resulted in lower severity and higher yields compared with other fungicides. The strobilurin fungicides provided the highest yields in many locations; however, severity tended to be higher than that of the triazole fungicides. There also were differences in yield and severity between the trials with two and three applications of several fungicides, with three applications resulting in less severe soybean rust and higher yields. However, the third application of tebuconazole, tetraconazole, and the mixtures containing azoxystrobin and pyraclostrobin was not needed to maintain yield. These fungicides were among the most effective for managing soybean rust and maintaining yield over most locations.
Variability in Distribution and Virulence Phenotypes of Heterodera glycines in Missouri During 2005
Authors: Mitchum Melissa G. , Wrather J. Allen , Heinz Robert D. , Shannon J. Grover , Danekas Gene
Published: October 2007

The soybean cyst nematode, Heterodera glycines, is a serious economic threat to soybean producers in Missouri. Periodic monitoring for the presence, population densities, and virulence phenotypes of H. glycines is essential for determining crop losses and devising management strategies implementing the use of resistant cultivars. A survey using area-frame sampling was conducted to determine the distribution and virulence phenotypes of H. glycines in Missouri during 2005. Two samples from each of 125 fields representing eight geographical regions of Missouri were collected; 243 samples were processed for extraction of cysts and eggs. In all, 49% of samples had detectable cyst nematode populations, which ranged from 138 to 85,250 eggs per 250 cm3 of soil. Race and H. glycines type tests were conducted on populations from 45 samples. Nearly 80% of the populations that were tested, irrespective of the region, were virulent on the indicator line plant introduction (PI) 88788, which is the source of resistance for most H. glycines-resistant cultivars. More than 70% of populations could reproduce on the indicator lines PI 88788, PI 209332, and PI 548316 (Cloud), indicating that soybean cultivars with resistance derived from these sources need to be carefully monitored and used only in rotation with nonhost crops and soybean cultivars with resistance from other sources. Approximately one-third of the populations, primarily in the southern regions of Missouri, could reproduce on PI 548402 (Peking), another common source of resistance. Fewer than 10% of the populations could reproduce on PI 90763, PI 437654, PI 89772, or PI 438489B, suggesting that these sources of resistance should be used in soybean breeding programs to develop H. glycines-resistant soybean cultivars.
Effect of Fertilization and Biopesticides on the Infection ofCatharanthus roseusbyPhytophthora nicotianae
Authors: Yandoc C. B. , Rosskopf E. N. , Shah D. A. , Albano J. P.
Published: October 2007

Experiments were carried out in a greenhouse to determine the effect of fertilizer concentration (0, 0.5, 1.0, and 2.0× Hoagland solutions) and various commercial biopesticides on the severity of Phytophthora nicotianae infection of Madagascar periwinkle. Application of biopesticides and fertilizer concentration significantly influenced the severity of infection, but there was no significant effect from the interaction of these two factors. Overall, disease severity showed a tendency to increase with the concentration of applied fertilizer. Compared with the control plants, disease was significantly less severe in plants that were treated with the biopesticides, except for plants treated with metabolites of Myrothecium verrucaria (DiTera). However, only the products containing potassium phosphonates and potassium phosphates (FNX-100 and FNX-2500) provided a satisfactory level of control when compared with either the control plants or those that received any of the other products tested. Additional experiments were carried out in growth chambers to test the effects of increasing fertilizer concentrations in plants that were inoculated with different P. nicotianae inoculum levels. In these trials, there was no consistent indication that disease is most severe in plants that received the highest fertilizer concentration even at the highest inoculum level.
Resistance to Puccinia polysora in Maize Accessions
Authors: Chávez-Medina J. Alicia , Leyva-López Norma E. , Pataky Jerald K.
Published: October 2007

A number of potential sources of general and specific resistance to southern corn rust were identified from 1,890 plant introduction accessions that were screened for reactions to Puccinia polysora race 9. Resistance appeared to differ among four accessions on which uredinia were not observed in initial screenings. Resistance to P. polysora in PI 186215 (Argentine inbred 2-687) was a chlorotic fleck, hypersensitive reaction that was conditioned by a single, dominant gene that was allelic with or very closely linked to the Rpp9 gene based on tests of allelism. All but 3 of 2,357 testcross progeny, (inbred 2-687 × Rpp9) × PS were resistant. Resistance in Ames 19016 (Va59) was effective in F1 progeny and appeared to be dominant and simply inherited; however, this resistance appeared to be a slow-rusting or incomplete resistance that was effective in adult plants but not in young seedlings. Severity of southern rust was less than 10% on resistant progeny from crosses with Va59 compared with severity exceeding 70% on susceptible progeny. Resistance in plant introduction (PI) 186209 (Venezuelan flint) and NSL 75976 (IA DS61) were not effective in F1 hybrid combination and, thus, probably have limited value in commercial maize. Resistance in PI 186209 may be conditioned by a single recessive gene and resistance in NSL 75976 may be co-dominant.
Comparative Efficacy of the New Postharvest Fungicides Azoxystrobin, Fludioxonil, and Pyrimethanil for Managing Citrus Green Mold
Authors: Kanetis Loukas , Förster Helga , Adaskaveg James E.
Published: October 2007

Three new fungicides (i.e., azoxystrobin, fludioxonil, and pyrimethanil) are currently being introduced for postharvest management of citrus green mold in the United States. The effectiveness of each fungicide was evaluated when applied alone (at 1,000 to 1,200 mg/liter) or in mixtures (at 500 mg/liter each component) to lemon fruit that were wound-inoculated with imazalil/thiabendazole (TBZ)-sensitive or -resistant isolates of Penicillium digitatum. In laboratory studies when aqueous fungicide solutions were applied 9 to 21 h after inoculation, pyrimethanil showed the highest level of green mold control. The efficacy of fludioxonil and azoxystrobin was very high at the early timings, but decreased as time after inoculation increased. Differences in fungicide performance were not due to multiple fungicide resistance, but more likely due to differences in fungicide mobility in fruit tissue. Azoxystrobin-fludioxonil mixtures were significantly more effective when compared to single-fungicide treatments. Mixtures of imazalil with pyrimethanil were the most effective in controlling decay. The efficacy of all fungicides was significantly lower when mixed into a packing fruit coating as compared to aqueous or storage fruit coating applications. In laboratory and packingline studies, the lowest incidence of green mold decay was obtained when azoxystrobin-fludioxonil and imazalil-pyrimethanil were applied as aqueous solutions that were followed by a fruit coating. Among the new fungicides, azoxystrobin and fludioxonil applied in water or storage fruit coating, respectively, provided the best anti-sporulation activity. Storage fruit coating improved the activity of both fungicides. Pyrimethanil was the least effective fungicide in suppressing sporulation of the pathogen on decaying fruit. Overall, among the mixtures, azoxystrobin-fludioxonil and TBZ-fludioxonil had high anti-sporulation activity in aqueous and storage fruit coating applications. New integrated management programs should be based on monitoring of fungicide sensitivities in pathogen populations, rotating mixtures of products with different modes of action, and using appropriate fungicide application strategies.
The Incidence of Root-Knot Nematodes Meloidogyne arenaria, M. incognita, and M. javanica on Vegetables and Weeds in Montenegro
Authors: Pajovic I. , Širca S. , Stare B. Geric , Urek G.
Published: October 2007

Root-knot nematodes (Meloidogyne spp.) are common pathogens that parasitize vegetables and other crops and cause significant yield reductions worldwide. In the early spring of 2006, severe plant stunting, chlorosis, and extensive root galling were observed on cucumber plants grown in a greenhouse on Zeta plain, Zetska ravnica, Montenegro. In the summer and autumn of 2006, infected roots of different crops were collected from greenhouses and vegetable production fields of Zeta plain, which represents the largest area of Montenegro's vegetable production. Several vegetable crops were found to be infected with root-knot nematodes, including tomato (Lycopersicon esculentum Mill.), squash (Cucurbita pepo L.), cucumber (Cucumis sativus L.), pepper (Capsicum annuum L.), and lettuce (Lactuca sativa L.). Symptoms on these crops included root-galling, leaf chlorosis, and stunting. Heavily infected tomato plants growing in two greenhouses also displayed early flower and fruit drop. Nematode species were determined based on characterization of (i) female perineal patterns, (ii) male and second-stage juvenile morphology (2,3), and (iii) esterase and malate dehydrogenase phenotypes (PhastSystem; Amersham Biosciences, Piscataway, NJ) from young egg-laying females (1). The most prevalent species was M. incognita, which was isolated from the roots of tomatoes, peppers, cucumbers, and lettuce from nine locations. Meloidogyne arenaria was detected at three locations from the roots of tomatoes grown in a greenhouse and the weeds Convolvulus arvensis L. and Solanum nigrum L., which were growing in open fields in separate locations. M. javanica was found on tomato and squash in the same field where M. arenaria was also found on S. nigrum. M. javanica was isolated from tomato and squash. In this study, we found high incidence of Meloidogyne spp. in intensive vegetable production areas of Montenegro. The implementation of an effective integrated pest management program is essential for future use of infested areas. To our knowledge, this is the first report of M. arenaria, M. incognita, and M. javanica from Montenegro.

References: (1) P. R. Esbenshade and A. C. Triantaphyllou. J. Nematol. 17:6, 1985. (2) S. B. Jepson. Identification of Root-Knot Nematodes. CAB International, Wallingford, UK, 1987. (3) G. Karssen. The Plant-Parasitic Nematode Genus Meloidogyne Göldi, 1892 (Tylenchida) in Europe. Koninklijke Brill NV, Leiden, the Netherlands, 2002.
First Report of Iris yellow spot virus in Spiny Sowthistle (Sonchus asper) in the United States
Authors: Nischwitz C. , Gitaitis R. D. , Mullis S. W. , Csinos A. S. , Langston D. B. , Sparks A. N.
Published: October 2007

Iris yellow spot virus (IYSV) is a member of the genus Tospovirus in the family Bunyaviridae. Its known host range is very limited, and the currently known hosts include onion, leek, lisianthus, and alstroemeria (2). The virus is vectored by onion thrips (Thrips tabaci). Onion (Allium cepa) is grown as a winter crop in Georgia from September to April and is the only known host commercially grown in the region. However, the virus has been found across the onion-growing region in the state every year since its first occurrence during 2003 (3). Consequently, the virus must oversummer in other host(s) or its insect vector. Accordingly, samples of weeds were collected in the vicinity of onion fields and cull piles in the Vidalia region and tested for the presence of IYSV by a double-antibody sandwich (DAS)-ELISA (Agdia, Inc., Elkhart, IN). One of three nonsymptomatic spiny sowthistle samples tested positive by ELISA for IYSV. Total RNA was extracted from the leaf using the RNeasy Plant Mini Kit (Qiagen, Valencia, CA) following the manufacturer's protocol. Two microliters were used for reverse transcription (RT)-PCR with the forward primer (5′-TCAGAAATCGAGAAACTT-3′) and reverse primer (5′-TAATTATATCTATCTTTCTTGG-3′) for the IYSV nucleocapsid gene (1). A band of the expected size (approximately 800 bp) was obtained and sequenced. The sequence from the sowthistle (GenBank Accession No. EU078327) matched IYSV sequences from Georgia and Peru in a BLAST search in GenBank (closest matches with Accession Nos. DQ838584, DQ838592, DQ838593, and DQ658242). This is to our knowledge, the first confirmed report of IYSV infecting spiny sowthistle. The distribution of IYSV in sowthistle and its role as an oversummering host for IYSV is currently an on-going study.

References: (1) L. du Toit et al. Plant Dis. 88:222, 2004. (2) D. H. Gent et al. Plant Dis. 90:1468, 2006. (3) S. W. Mullis et al. Plant Dis. 88:1285, 2004.
First Report of Fusarium Wilt of Coreopsis verticillata ‘Moonbeam’ Caused by Fusarium oxysporum in a Midwestern Nursery
Authors: Elmer W. H. , Daughtrey M. , Rane K. , Jimenez-Gasco M. M.
Published: October 2007

Disease symptoms were observed in a commercial nursery in the midwest on Coreopsis verticillata ‘Moonbeam’ during the summer of 2006. Plants in a roughly circular area in one field showed foliar necrosis, stem basal cankers, root rot, and eventually plant death. Vascular discoloration was noted in stems of affected plants. Sporulation typical of Fusarium oxysporum was observed on the surface of cankers. Five isolates of F. oxysporum (KR1, KR2, KR4, MDU, and MDL) were taxonomically identified from monosporic cultures obtained from surface-disinfested stems and roots. All five isolates were vegetatively compatible with each other. Two methods of inoculation were used. Method one (conidial drench) involved pouring 100 ml of conidial suspension (106 conidia per ml) into 10-cm pots containing one healthy 2-month-old division of the same cultivar that was obtained from a different nursery. Method two (millet infestation) involved mixing autoclaved millet seed that had been colonized by each isolate into potting mix (2.5 g/L of mix) prior to transplanting. Four plants were tested per isolate per method and controls received distilled water or autoclaved millet. After 3 months, only two isolates (KR1 and KR2) inoculated by conidial drench caused root rot, whereas all isolates inoculated by millet infestation caused wilt, root rot, and vascular discoloration, and all inoculated plants died after 3.5 months Controls remained healthy. The fungus was recovered and was vegetatively compatible with the original F. oxysporum isolates. The tef-α gene from two F. oxysporum isolates was sequenced, submitted to the Blast ID search at Pennsylvania State University (1), and found to belong to the F. oxysporum species complex. Two isolates (KR1 and KR 2) have been deposited at the Fusarium Research Center at Pennsylvania State University under deposition numbers O-2437 and O-2438. Because of the popularity of this coreopsis cultivar, this disease has the potential to cause significant economic loss in nurseries and landscape businesses. The affected nursery, however, has taken all precautions to avoid disseminating the pathogen.

Reference: (1) D. M. Geiser et al. Eur. J. Plant Pathol. 110:473, 2004.
Population Subdivision of Fusarium graminearum Sensu Stricto in the Upper Midwestern United States
Authors: Gale L. R. , Ward T. J. , Balmas V. , Kistler H. C.
Published: October 2007

A collection of 712 Fusarium graminearum sensu stricto (s.s.) strains, predominantly gathered between 1999 and 2000 from nine states within the United States, was examined for population structure and polymerase chain reaction-based trichothecene type. Most strains belonged to a cohesive genetic population characterized by a 15-acetyldeoxynivalenol (15ADON) trichothecene type. However, using a Bayesian model-based clustering method, we also identified genetically divergent groups of strains in some sampled locations of Minnesota and North Dakota. Strains of the major group of divergent populations were of a 3ADON trichothecene type and formed a distinct cluster with a collection of previously gathered strains from Italy, which displayed all three trichothecene types (15ADON, 3ADON, and nivalenol). The co-existence of genetically divergent populations of F. graminearum s.s. in the Upper Midwest allows for the rejection of the hypothesis that F. graminearum s.s. in the United States consists of a single population. These results also suggest that recombination has been insufficiently frequent in this homothallic (selfing) fungal species to homogenize the divergent populations observed in the Upper Midwest.
Molecular Characterization and Diagnosis of QoI Resistance in Cucumber and Eggplant Fungal Pathogens
Authors: Ishii H. , Yano K. , Date H. , Furuta A. , Sagehashi Y. , Yamaguchi T. , Sugiyama T. , Nishimura K. , Hasama W.
Published: October 2007

The molecular mechanism of QoI fungicide resistance was studied using isolates of cucumber Corynespora leaf spot fungus (Corynespora cassiicola) and the eggplant leaf mold (Mycovellosiella nattrassii). In both pathogens, a mutation at position 143 from glycine to alanine (G143A) was detected in the cytochrome b gene that encodes for the fungicide-targeted protein. Moreover, the nucleotide sequence at amino acid position 143 was converted from GGT or GGA in sensitive (wild-type) to GCT or GCA in resistant (mutant-type) isolates. The methods of polymerase chain reaction restriction fragment length polymorphism commonly used for QoI resistance monitoring were employed successfully, leading to the amplified gene fragment from resistant isolates being cut with the restriction enzyme ItaI. However, heteroplasmy (the coexistence of wild-type and mutated alleles) was found when the resistant isolates of C. cassiicola, M. nattrassii, and Colletotrichum gloeosporioides (strawberry anthracnose fungus) were subcultured in the presence or absence of QoI fungicides. QoI resistance of cucumber powdery and downy mildew isolates persisted for a few years following the removal of the selection pressure imposed by the fungicide under both laboratory and commercial greenhouse conditions. The proportion of mutated sequences in cytochrome b gene decreased over time in the pathogen population. The protective efficacy of the full dose of azoxystrobin decreased when the populations of powdery and downy mildews contained resistant isolates at 10%. Using FMBIO, a fluorescence bio-imaging analyzer, the mutant allele from the QoI-resistant isolates could be detected at the level of 1%, whereas the detection sensitivity of ethidium-bromide-stained gels was ≈10 times lower.
Controlled Laboratory System to Study Soil Solarization and Organic Amendment Effects on Plant Pathogens
Authors: Klein Eyal , Katan Jaacov , Austerweil Miriam , Gamliel Abraham
Published: October 2007

A controlled laboratory system for simulating soil solarization, with and without organic amendment, was developed and validated using physical, chemical, and biological parameters. The system consists of soil containers that are exposed to controlled and constant aeration, and to temperature fluctuations that resemble those occurring during solarization at various depths. This system enables a separate analysis of volatiles and other components. We recorded a sharp decrease in oxygen concentration in the soil atmosphere followed by a gradual increase to the original concentration during solarization in the field and heating in the simulation system of soil amended with wild rocket (Diplotaxis tenuifolia) or thyme (Thymus vulgaris). The combined treatment of organic amendment and solarization (or heating in the controlled system) was highly effective at controlling populations of Fusarium oxysporum f. sp. radicis-lycopersici. Changes in soil pH, enzymatic activities, and microbial populations followed, in most cases, trends which were similar under both solarization and the heating system, when exposed to controlled aerobic conditions. The reliability and validity of the system in simulating physical, chemical, and biological processes taking place during solarization is demonstrated.
Beyond the Sovereign Debt Crisis: Alternative Forms of Market‐Based Debt Restructuring Schemes
Authors: Corrado Luisa
Published: October 2007

Abstract

The resolution of the international debt crises has stimulated extensive research onhow to design solutions for countries facing external debt overhang problems. Thispaper analyses the benefits for creditors and debtors of the following `market‐based'debt restructuring schemes: (i) issue of collateralised new assets inexchange for the old debt; (ii) automatic roll‐over of the debt repayment with astate‐contingent penalty rate. The first proposal combines the basic debt conversionscheme proposed by Krugman (1989) with Cline's proposal (1995) of self‐enhancementson the new claims as a form of risk‐compensation for creditors (seealso Williamson, 1988). Under this scheme the debtor country modifies the streamof the debt service payments by voluntarily exchanging the outstanding debt fornew assets with different debt service characteristics where the principal and/or theinterest rate payment can be fully or partially collateralised. The roll‐over schemeentitles illiquid countries to extend the outstanding debt for a specified period at apenalty rate which is contingent on a measure of the country's creditworthiness.This solution has the desirable effect of reducing the future contractual obligationsby lowering the penalty rate on the excess of debt rolled over, thus helping thedebtor country to use additional resources to invest in the economy.
Papillary haemangioma. A distinctive cutaneous haemangioma of the head and neck area containing eosinophilic hyaline globules
Authors: Suurmeijer A J H , Fletcher C D M
Published: October 2007

Aims:  To investigate and define a morphologically distinctive group of cutaneous papillary haemangiomas.

Methods and results:  Eleven patients (seven male, four female, age range 1–77 years, median 57) were identified with a solitary bluish cutaneous papule (median size 11 mm) arising in the head and neck region. Most lesions had been present for several years. None of the patients had associated systemic disease or polyneuropathy, organomegaly, endocrinopathy, M‐protein, skin changes (POEMS) syndrome. Only one lesion recurred locally. The lesions showed predominantly intravascular papillary growth within multiple ectatic dermal vessels. The papillae had cellular cores containing pericytes and stromal cells, arranged around normal small capillaries. The surfaces of the papillae were covered by focally swollen endothelial cells containing numerous hyaline globules, ultrastructurally representing giant lysosomes containing organelle debris and fat vacuoles (so‐called thanatosomes). These endothelial cells were immunopositive for CD31 and CD34 but negative for D2‐40 (podoplanin).

Conclusions:  Papillary haemangioma is a distinctive benign cutaneous lesion containing eosinophilic hyaline globules consistent with dysfunction of the autophagocytic–lysosomal pathway.
Epidermal transient receptor potential vanilloid 1 in idiopathic small nerve fibre disease, diabetic neuropathy and healthy human subjects
Authors: Wilder‐Smith E P , Ong W‐Y , Guo Y , Chow A W‐L
Published: October 2007

Aims: The transient receptor potential vanilloid 1 (TRPV1) plays an important role in mediating pain and heat. In painful neuropathies, intraepidermal TRPV1 nerve fibre expression is low or absent, suggesting that pain generated is not directly related to sensory nerve fibres. Recent evidence suggests that keratinocytes may act as thermal receptors via TRPV1. The aim was to investigate epidermal TRPV1 expression in patients with neuropathic conditions associated with pain.

Methods and results: In a prospective study of distal small nerve fibre neuropathy (DISN;n = 13) and diabetic neuropathy (DN;n = 12) intraepidermal nerve fibre density was assessed using the pan axonal marker PGP 9.5 and epidermal TPVR1 immunoreactivity compared with controls (n = 9). Intraepidermal nerve fibres failed to show TRPV1 immunoreactivity across all groups. There was moderate and strong TRPV1 reactivity of epidermal keratinocytes in 41.8% and 6% for DISN, 32.9% and 2.9% for DN and 25.4% and 5.1% for controls, respectively. Moderate keratinocyte TRPV1 expression was significantly increased in DISN compared with controls (P = 0.01).

Conclusion: Our study suggests that in human painful neuropathies, epidermal TRPV1 expression is mainly in keratinocytes.
Gene‐expression signature of adhesion/growth‐regulatory tissue lectins (galectins) in transitional cell cancer and its prognostic relevance
Authors: Langbein S , Brade J , Badawi J K , Hatzinger M , Kaltner H , Lensch M , Specht K , André S , Brinck U , Alken P , Gabius H‐J
Published: October 2007

Aims:  Lectins, and especially galectins, appear to be important in malignancy‐associated processes. The aim was to analyse comprehensively the presence of galectins in urothelial tumours.

Methods and results:  Non‐cross‐reactive antibodies against seven family members from the three subgroups (prototype: galectin‐1, ‐2 and ‐7; chimera type: galectin‐3; tandem‐repeat type: galectin‐4, ‐8 and ‐9) were used. Gene expression was monitored in specimens of normal urothelium, fresh tumour tissue and cell lines by real‐time polymerase chain reaction (PCR). The presence and evidence of tumour‐associated up‐regulation were shown for galectin‐1 and ‐3. This was less clear‐cut for galectin‐4 and ‐8. Galectin‐7 was expressed in all cell lines; galectin‐2 and ‐9 were detected at comparatively low levels. Galectin‐2, ‐3 and ‐8 up‐regulation was observed in superficial tumours, but not in muscle‐invasive tumours (P < 0.05). Immunoreactivity correlated with tumour grading for galectin‐1, ‐2 and ‐8, and disease‐dependent mortality correlated with galectin‐2 and ‐8 expression. Binding sites were visualized using labelled galectins.

Conclusions:  The results demonstrate a complex expression pattern of the galectin network in urothelial carcinomas. Galectin‐1, ‐2, ‐3 and ‐8 are both potential disease markers and also possible targets for bladder cancer therapy.
Cyclin D1 and p16 expression in pleomorphic adenoma and carcinoma ex pleomorphic adenoma of the parotid gland
Authors: Patel R S , Rose B , Bawdon H , Hong A , Lee C S , Fredericks S , Gao K , O’Brien C J
Published: October 2007

Aims:  To compare cyclin D1 and p16ink4 (p16) expression in normal tissue, pleomorphic adenoma (PA) and carcinoma ex pleomorphic adenoma (CXPA) of the parotid gland.

Methods and results:  Immunohistochemistry was used to examine cyclin D1 and p16 expression in 43 parotid tumours (29 PAs and 14 CXPAs). Cyclin D1 and p16 were both significantly more likely to be expressed in the neoplastic than in the normal epithelial and stromal components of PA and CXPA (P < 0.001 and P < 0.005, respectively). Cyclin D1 was more likely to be expressed in the malignant components of CXPA than in the benign components of PA (50% versus 31% and 31%, respectively), but the trend was not statistically significant. There was no evidence of this association for p16 (corresponding positivity rates 69% versus 81% and 52%).

Conclusions:  Our findings provide preliminary evidence of roles for cyclin D1 and p16 in the development of PA and for cyclin D1 in the progression of PA to CXPA.
Epidermal growth factor receptor (EGFR) gene copy number detection in non‐small‐cell lung cancer; a comparison of fluorescence in situ hybridization and chromogenic in situ hybridization
Authors: Ruiz M I Gallegos , Floor K , Vos W , Grünberg K , Meijer G A , Rodriguez J A , Giaccone G
Published: October 2007

Aims:  The epidermal growth factor receptor (EGFR) is an important target for anticancer therapy. In non‐small‐cell lung cancer (NSCLC), mutations in the tyrosine kinase domain of EGFR and EGFR gene copy number have been demonstrated to identify patients most likely to benefit from EGFR tyrosine kinase inhibitors. EGFR gene copy number has been assessed mainly by fluorescence in situ hybridization (FISH), a method requiring the use of a fluorescence microscope and often hampered by the rapid fading of the fluorescent signal. These limitations of FISH can be overcome by using chromogenic in situ hybridization (CISH). To test the applicability of CISH for EGFR gene copy number testing in NSCLC, a comparison of CISH and FISH was performed.

Methods and results:  A total of 58 formalin‐fixed, frozen NSCLC tissue samples were collected on which both CISH and FISH were performed. High concordance was found in the assessment of EGFR copy number between observers and between techniques (κ coefficient = 0.64–0.76). CISH seemed the ideal technique for paraffin sections, whereas FISH was favourable for frozen material.

Conclusions:  CISH is a suitable alternative strategy to FISH in determining EGFR gene copy number in NSCLC patients.
Trypanosoma brucei infection in nude mice: B lymphocyte function is suppressed in the absence of T lymphocytes
Authors: CLAYTON CHRISTINE E. , OGILVIE BRIDGET M. , ASKONAS BRIGITTE A.
Published: October 2007

Summary B lymphocyte function was assessed in outbred nude mice and nu/+ controls infected with Trypanosoma brucei brucei. On day 10 of the infection in outbred nu/nu mice in which the initial wave of parasites was strongly controlled, B cell function was unaltered or enhanced compared with uninfected animals or infected nu/+. In other nu/nu mice unable to control the initial parasitaemia, thymidine incorporation and Ig secretion by spleen cells were increased on day 10 and their response to lipopolysaccharide in vitro negated. By day 15 however, even the spleen cells of infected nu/nu which controlled the initial wave of parasites were proliferating and secreting Ig on removal from the mice and they were unable to respond to LPS in vitro.

These experiments confirm results of a previous study of B cell function in T cell‐depleted mice (Askonas et al. 1979). T. b. brucei infection of mice causes both enhanced Ig production and suppression of the ability of B cells to respond to mitogen even in the absence of T cells, but the presence of T cells may accelerate the changes which occur in B lymphocytes following this infection.
Membrane fractions of trypanosomes mimic the immunosuppressive and mitogenic effects of living parasites on the host
Authors: CLAYTON CHRISTINE E. , SACKS D.L. , OGILVIE BRIDGET M. , ASKONAS BRIGITTE A.
Published: October 2007

Summary African trypanosomiasis in mice leads to profound changes in lymphoid tissues. In an attempt to define the nature of the trypanosome stimulus, we have studied the effect of radio‐attenuated trypanosomes and their subcellular fractions in vivo. We find that relatively low doses of irradiated Trypanosoma brucei S42 injected into (CBA/H × C57B1/ 6) F1 mice mimicked the previously reported effects of infective parasites. 2 × 107 irradiated trypanosomes caused a greater than two‐fold increase in spleen weight accompanied by a roughly 10‐fold increase in background plaque forming cells (PFC) to sheep red blood cells (SRBC). The primary response to SRBC was significantly enhanced when priming was carried out on the day of trypanosome injection, but significantly suppressed when carried out 3 days later. Disruption of trypanosomes by freeze‐thawing did not destroy their mitogenic or immunosuppressive activities. A membrane fraction collected by high speed centrifugation (150 000 × g) after removal of larger organelles at 12 000 × g retained both mitogenic and suppressive activities. The high speed supernatant lost the ability to enhance background PFC, but still caused partial immunosuppression with a much lower potency than the membrane pellet. Whether immunosuppression and enhanced PFC levels relate to the same parasite product is not clear as yet, but both effects can be ascribed to a membrane fraction of the parasite.
Fasciola hepatica: changes in tegument during killing of adult flukes surgically transferred to sensitized rats
Authors: BENNETT C.E. , HUGHES D.L. , HARNESS E.
Published: October 2007

Summary Adult Fasciola hepatica were placed intraperitoneally into rats which had been sensitized by an oral infection of 20 metacercariae given 3–5 weeks previously. Implanted flukes were recovered at intervals during the next 24 h. Wax embedded sections of flukes and surface impressions of attached cells were examined by light microscopy (LM). Flukes were also examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In all stages, post transplantation, increased secretory activity was noted at the tegu‐mental surface both by the blebbing of membrane and the formation of microvilli. Monitoring of the surface by SEM revealed attachment of very few cells (less than 100/sq mm) in the first hour. By TEM some of these were found to be eosinophils. At 1.5 h local palisading of cells, mainly eosinophils, occurred. Many of these degranulated at a distance from the parasite. Between 2 and 4 h many more neutrophils and macrophages were found, with fewer eosinophils. In the period up to 4 h the tegumental syncytium became charged with abnormally high concentrations of secretory granules and the surface membrane was maintained often enclosing apparently damaged areas. No cells penetrated the syncytium at this stage. Between 4 and 12 h the number of secretory granules in the tegument declined. Around 12 h the remaining granules contributed to the formation of large irregular microvilli. It was at this stage that neutrophils, macrophages and occasional eosinophils moved into the syncytium and began to lift it from beneath.
The role of natural killer (NK) cells in resistance to herpes simplex virus I (HSV‐I) infection
Authors: RAGER‐ZISMAN B. , ALLISON A.C.
Published: October 2007

Summary Pretreatment of mice with cyclophosphamide (CY) increases susceptibility of adult mice to herpes simplex type I (HSV‐I) infection. In searching for a CY sensitive mechanism, our attention has been focused on natural killer (NK) cells. Activity of these cells was increased in spleens of adult mice after inoculation with HSV‐I and depressed after CY administration. The timing of recovery of NK cell activity after the administration of CY, was consistent with a role for these cells in collaboration with immune T lymphocytes when transferred to pre‐treated, virus infected animals. It is postulated that sensitized T lymphocytes reacting with virus antigens release products that activate macrophages which in turn produce interferon. Interferon increases NK cell activity and NK cells inhibit viral replication. A correlation between resistance to HSV‐I infection and NK cell activity of CBA or C57BL/10 mice was found. It is suggested that NK cells play a role in defence, not only against tumour cells, but also against a wide range of infective agents.
Genetic control of immunity to parasites. Infection with Trichinella spiralis in inbred and congenic mice showing rapid and slow responses to infection
Authors: WAKELIN D.
Published: October 2007

Summary Strain variation in the response of inbred mice to infection with Trichinella spiralis was reflected in the length of survival of the adult worms, their fecundity and in the number of muscle larvae acquired. Three strains, NIH, SWR and DBA1 (all H2q), responded rapidly, expelled most of the adult worms within 12 days and had relatively low burdens of muscle larvae. B10 mice (H2b) and five related strains (B10.G (H2q), B10.BR (H2k), B10.AKM (H2d), B10.AKM (H2m) and B10.T(6R) (H2y2)) responded slowly, retaining adults for more than 12 days and acquiring heavy muscle burdens. The slow response of B10 mice was evident in both old and young mice, in primary and secondary infections and was inherited as a recessive characteristic. No evidence was obtained that slow responsiveness resulted from suppressor cell activity. The results are discussed in relation to the influence of genes located within and without the major histocompatibility complex.
Cellular reactions in tongue and gut in murine trichinellosis and their thymus‐dependence
Authors: GUSTOWSKA LEOKADIA , RUITENBERG E.J. , ELGERSMA ANNEKE
Published: October 2007

Summary Histological changes in gut, tongue and three lymphoid tissues (spleen, mesenteric and mandibular lymph nodes) which occurred after oral infection of both thymus‐bearing and congenitally athymic mice with the nematode Trichinella spiralis were studied by light microscopy for 42 days. The basophilic transformation and the enzyme cytochemical changes of tongue muscle fibers in connection with the larval encystation occurred in both groups of animals and was thus thymus‐independent. A cellular inflammatory reaction including eosinophils, mononuclear cells and mast cells in the parasitized tongue occurred in both groups, albeit to a lesser extent in the athymic animals. The kinetics of this cellular response were the same in both groups. Eosinophilia in the gut was observed in thymus‐bearing mice only during the early phase of infection and in athymic mice in the latter part of the observation period, suggesting a partial thymus‐independence of the phenomenon. Typical immunohistological changes in the lymphoid tissues and antibody production occurred only in the thymus‐bearing animals. The cellular reactions in the parasitized gut and tongue can only partially be explained by a delayed hypersensitivity aetiology.
Antibody suppression in mice infected with Nippostrongylus brasiliensis
Authors: HAIG D.M. , LIMA GLORIA C. , MOTA I.
Published: October 2007

Summary A/SN mice infected with N. brasiliensis showed depressed anti‐DNP antibody responses following immunization with DNP‐Asc in alum. The immunosuppression was only observed when infection preceded immunization by between 2 and 7 days, and was not achieved when the interval was extended to 10 days. The suppression lasted at least 50 days, and affected IgE levels more than IgGl or IgG agglutinating anti‐DNP antibodies. A high dose of infective larvae (500–1000 per mouse) was necessary to induce suppression. Use of low dose irradiation indicated a parasite‐induced radiosensitive component of the mouse immune system which negatively regulated the anti‐DNP IgE response. These results suggested that the parasite could induce suppression in an analogous manner to sequential antigen‐induced suppression (AIS).
In vitro study of immunological events in human and experimental schistosomiasis: relationships between cytotoxic antibodies and circulating Schistosoma antigens*
Authors: CAPRON MONIQUE , CARLIER Y. , NZEYIMANA H. , MINOPRIO PAOLA , SANTORO F. , SELLIN B. , CAPRON A.
Published: October 2007

Summary Complement‐dependent cytotoxic antibodies were found in 54% of Schistosoma mansoni infected patients from Burundi and in 69 to 78% of Schistosoma mansoni infected Brazilian patients. The levels of cytotoxic Ab were not statistically different in sera from infected mothers and from their newborn children, suggesting a transfer through the placenta. A sandwich radioimmunoassay (SRIA) and the Radioimmunoprecipitation‐PEG assay (RIPEGA) technique were used in order to detect respectively total schistosome circulating soluble antigens (CSA), and schistosome antigen ‘4’ in sera from infected patients. An inverse relationship was found between the presence of cytotoxic Ab and both total CSA and antigen ‘4′. The cytotoxic Ab and total CSA levels were followed in five Erythrocebus patas monkeys for 30 weeks after Schistosoma mansoni infection. As in human schistosomiasis the presence of cytotoxic Ab was found to be inversely correlated with the presence of total CSA. The blocking role of Schistosoma mansoni antigens in a complexed form was suggested by the inhibitory effect of the ultracentrifugation pellet of infected human serum on the cytotoxic activity. Moreover, the CSA absorption of infected monkey serum by passage through an anti‐CSA immunosorbent significantly increased the cytotoxic activity. Possible mechanisms for the inhibitory role of circulating immune complexes on complement‐dependent cytotoxic activity are discussed.