Germination of Fusarium graminearum Ascospores and Wheat Infection are Affected by Dry Periods and by Temperature and Humidity During Dry Periods.

The effects of temperature and relative humidity (RH) on germination of Fusarium graminearum ascospores, and of dry periods (DP) of different lengths and of temperature and RH during DP on ascospore survival were studied both in vitro and in planta. Optimal temperatures for ascospore germination at 100% RH were 20 and 25°C; germination was ≤5% when ascospores were incubated at 20°C and RH ≤ 93.5%. Viable ascospores were found at all tested combinations of DP duration (0 to 48 h) × temperature (5 to 40°C) or RH (32.5 to 100% RH). Germination declined as DP duration and temperature increased. Germination was lower for ascospores kept at 65.5% RH during the DP than at 76.0, 32.5, or 93.5% RH. Equations were developed describing the relationships between ascospore germination, DP duration and temperature or RH during DP. Durum wheat spikes were inoculated with ascospores and kept dry for 0 to 48 h at approximately 15°C and 65% RH; plants were then kept in saturated atmosphere for 48 h to favor infection. Fungal biomass, measured as F. graminearum DNA by quantitative polymerase chain reaction, declined as DP increased to 24 and 48 h at 3 and 9 days postinfection but not in spikes at maturity.

Rescue therapy with polymyxin B hemoperfusion in high-dose vasopressor therapy refractory septic shock.

BACKGROUND: Refractory septic shock (RSS) requiring major vasopressor support is associated with high mortality, especially in Gram-negative infections. The study aim was to describe hemodynamics, organ failure, and clinical outcomes in high-dose vasopressor therapy (HDVT) RSS patients treated with Polymyxin B hemoperfusion (PMX-HP) as rescue therapy. METHODS: We retrospectively analyzed 52 patients, unresponsive to conventional therapy, treated with two sessions of PMX-HP requiring HDVT (norepinephrine and/or epinephrine requirement (NEP+EP) ≥ 0.5 µg/kg/min), ≥ 2 organ failures, and suspected/confirmed Gram-negative infection from any source. RESULTS: At baseline, mean arterial pressure (MAP) was 80 ± 13 mmHg and NEP + EP requirement was 1.11 ± 0.56 µg/kg/min. After two PMX-HP sessions, at 72 h, MAP significantly increased and NEP + EP requirement decreased respectively by 12% and 76%. Pulmonary and renal function also improved significantly. Thirty patients (58%) showed a ≥ 50% reduction in NEP + EP dose within only 24 h after the first PMX-HP session (early responders), and 22 did not or died from irreversible shock in the same time frame (early non-responders). The 30-day hospital mortality was 29%; it was 16% in early responders and 45% in early non-responders. On multivariate analysis, SAPS II score, vasopressin, and central venous pressure significantly affected 30-day hospital mortality. CONCLUSION: This is the first study describing the use of PMX-HP as a rescue therapy in RSS patients with HDVT and MOF. Our results suggest a possible role for PMX-HP in improving hemodynamics, organ function, and mortality in RSS, with a 30-day survival of up to 70%.

Influence of temperature on infection, growth, and mycotoxin production by Fusarium langsethiae and F. sporotrichioides in durum wheat.

Information concerning the temperature requirements of the species causing Fusarium head blight of small grains is essential for understanding which species cause the disease in different areas and years, for developing weather-driven disease models, and for predicting mycotoxin type and quantity in kernels. The optimal temperature range for growth was 20-25 °C for Fusarium langsethiae and 25-30 °C for F. sporotrichioides, and the optimum for production of both T-2 and HT-2 toxins was 15 °C for F. langsethiae and 10-15 °C for F. sporotrichioides. Floret infection occurred from 10 to 40 °C for F. sporotrichioides (69.8% average incidence of infected florets) and from 10 to 35 °C for F. langsethiae (17.6% of infected florets). The optimal temperature for spike colonisation was 25 °C for F. langsethiae and 30 °C for F. sporotrichioides, and the optimal temperature range for mycotoxin production was 15-35 °C for F. langsethiae and 20-25 °C for F. sporotrichioides. The quantity of fungal DNA in inoculated spikes was 5.5-times greater for F. sporotrichioides than for F. langsethiae; F. langsethiae DNA was first detected 2 days post-inoculation (dpi), and F. sporotrichioides DNA was first detected 4 dpi. Toxins were first detected 4 and 2 dpi for F. langsethiae and F. sporotrichioides, respectively.

In vitro antifungal activity of terpinen-4-ol, eugenol, carvone, 1,8-cineole (eucalyptol) and thymol against mycotoxigenic plant pathogens.

The aim of this study was to examine the effect of five naturally occurring compounds from essential oils on 10 different species of mycotoxigenic fungi involved in several plant diseases. The antifungal activities of terpinen-4-ol, eugenol, carvone, 1,8-cineole (eucalyptol) and thymol were observed in vitro on Fusarium subglutinans, Fusarium cerealis, Fusarium verticillioides, Fusarium proliferatum, Fusarium oxysporum, Fusarium sporotrichioides, Aspergillus tubingensis, Aspergillus carbonarius, Alternaria alternata and Penicillium sp. The naturally occurring compounds tested showed toxic effects on in vitro mycelium growth of all fungal species but with different level of potency. The results are encouraging for further investigations of in planta antifungal activities of these essential oils components.

Identification and validation of reference genes for gene expression studies in water buffalo.

In gene expression analysis, a key step to obtain informative data from reverse transcription quantitative PCR (RT qPCR) assay is normalization, that is usually achieved by ratio to correct the abundance of the gene of interest against that of an endogenous reference gene. The finding of such reference genes, ideally expressed in a stable way in multiple tissue samples and in different experimental conditions, is a non-trivial problem. In this work, a set of genes potentially useful as reference for gene expression studies in water buffalo has been identified and evaluated. In the first step, a publicly available Bos taurus expressed sequence tags database has been downloaded from the TIGR Gene Index and mined by some simple frequency algorithms to find out which tentative consensuses are present in a remarkable number of different cDNA libraries and, consequently, are more suitable to be included in a starter set of candidate reference genes. To validate the potential of such candidates for their use as normalizers in buffalo gene expression analysis, an RT qPCR analysis has been carried out, in which the expression stability of these genes has been evaluated on a panel of buffalo tissues and organs. Our results indicate that ribosomal proteins L4 and L5 and Gek protein encoding genes can be useful as normalizers to compare gene expression levels across tissues and organs in buffalo.

Assessment of Fusarium infection in wheat heads using a quantitative polymerase chain reaction (qPCR) assay.

The accuracy of a quantitative polymerase chain reaction assay in quantifying the DNA of trichothecene-producing F. culmorum and F. graminearum within harvested wheat grains and head tissue was evaluated in comparison with incidences of infected kernels and deoxynivalenol levels. In a first experiment, six durum and bread wheat varieties were grown in randomized plots for a 2-year period, and inoculated with Fusarium macroconidia at six growth stages between heading and dough ripening, to obtain a wide range of Fusarium head blight incidences. There was a close relationship between fungal DNA and the amount of deoxynivalenol, and this relationship was consistent over Fusarium species, wheat species and varieties, and over a wide range of Fusarium head blight infection. In a second experiment potted wheat plants were grown under environmentally controlled conditions and inoculated with the two Fusarium species at full flowering; head samples were collected before inoculation and after 6 h to 12 days, and processed by the quantitative polymerase chain reaction assay. This assay made it possible to detect the dynamic of fungal invasion in planta after infection had occurred, and to single out the presence of infection before the onset of the disease symptoms: A robust detection of the infection occurred within 18-24 h for F. culmorum, and within 2-9 days for F. graminearum.

In vitro antifungal activity of the tea tree (Melaleuca alternifolia) essential oil and its major components against plant pathogens.

AIMS: The aim of this study was to examine the effect of Melaleuca alternifolia essential oil (TTO) and its principal components on four cereal-pathogenic fungi. METHODS AND RESULTS: The antimycotic properties of TTO and of terpinen-4-ol, gamma-terpinen and 1,8-cineole (eucalyptol) were evaluated in vitro on Fusarium graminearum, Fusarium culmorum and Pyrenophora graminea. Moreover, barley leaves infected with Blumeria graminis were treated with whole TTO. All the tested fungi were susceptible to TTO and its components. CONCLUSIONS: TTO exerted a wide spectrum of antimycotic activity. Single TTO purified components were more active than the whole oil in reducing in vitro growth of fungal mycelium and, among the tested compounds, terpinen-4-ol was the most effective. SIGNIFICANCE AND IMPACT OF THE STUDY: TTO and its components can be considered potential alternative natural fungicides.

Treatment of critical bleeding in trauma patients.

AIM: Massive haemorrhage after trauma is a big challenge for care-givers, being a leading cause of early in-hospital mortality. Surgical bleeding may be easily controlled with several techniques. Otherwise, consumptive coagulopathy is often extremely difficult to stop. An adjunctive strategy to treat traumatic coagulopathic bleeding is recombinant activated factor VII (rFVIIa) (NovoSeven, Novo Nordisk A/S, Bagsvaerd, Denmark). METHODS: All major trauma victims haemodinamically unstable (systolic blood pressure < 90 mmHg or > 90 mmHg with massive infusions or vasopressors) admitted to the Emergency Department of the Niguarda Ca' Granda Hospital in Milan from October 2002 to September 2005 were reviewed. Mechanical bleeding was controlled with interventional techniques when indicated. Blood derivatives were administrated to maintain haemoglobin> 7 g/dL, INR < 1.5, fibrinogen > 1 and platelet count > 50 x 109. Off-label administration of rFVIIa was performed in the last year in any coagulopathic salvageable patient when all other strategies failed to control bleeding. RESULTS: Major trauma were 942, mean age 32.49+/-18.44 years, 94% blunt trauma, 25.13% haemodynamically unstable. Deaths occurred in 17.02% of cases before any procedure. Emergency invasive treatments were performed in 72.34% of cases. Infusions restored haemodynamic stability in 10.63% of patients. In average 9.4+/-4.1 units of red blood cells were transfused in unstable patients. rFVIIa (dosing 60-100 mg/kg) was administrated in 12 patients. Mortality occurred in 33.33% of cases. The principal cause of death was brain injury. A femoral artery thrombosis was observed in a mangled leg. No other adverse effects due to rFVIIa were documented. CONCLUSIONS: Off-label administration of rFVIIa was able to reverse life-threatening bleeding not manageable with standard strategies in our series of major trauma patients without systemic adverse effects.

From single genes to co-expression networks: extracting knowledge from barley functional genomics.

The paper reports an 'in silico' approach to gene expression analysis based on a barley gene co-expression network resulting from the study of several publicly available cDNA libraries. The work is an application of Systems Biology to plant science: at the end of the computational step we identified groups of potentially related genes. The communities of co-expressed genes constructed from the network are remarkably characterized from the functional point of view, as shown by the statistical analysis of the Gene Ontology annotations of their members. Experimental, lab-based testing has been carried out to check the relationship between network and biological properties and to identify and suggest effective strategies of information extraction from the network-derived data.

Real-time PCR for the detection of Escherichia coli O157:H7 in dairy and cattle wastewater.

AIMS: Developing and evaluating a rapid real-time polymerase chain reaction (PCR) method for the identification of Escherichia coli O157:H7 in cattle and dairy wastewater samples produced from mozzarella cheese factories, without pre-enrichment step before DNA extraction. METHODS AND RESULTS: Wastewater samples were collected from a dairy farm producing mozzarella cheese and located in Puglia (south of Italy). Plate count and other microbial assays were performed 1 h after sampling. Wastewater samples were artificially inoculated with 10(4), 10(7) and 10(8) cells ml(-1) of E. coli O157:H7, strain EDL933. PCR protocols for stx1, stx2 and eae genes were first tested on pure DNA extracted from type strains, in order to optimize the amplification conditions and reagent concentration before real-time PCR experiments. Three specific fragments of ca 106, 150 and 200 bp corresponding to genes eae, stx1 and stx2, respectively, were obtained. Real-time PCR experiments were performed with DNA extracted from dairy and manure wastewater samples inoculated with 10(4), 10(7) and 10(8) colony-forming units (CFU) ml(-1) of E. coli O157:H7 strain EDL 933. The sensitivity limit of the assay was 10(-1) pg microl(-1) for eae, stx2 and 16SrRNA, and 1 pg microl(-1) for stx1 gene respectively. CONCLUSIONS: A real-time PCR protocol has been developed and used in order to identify potential pathogens in dairy wastewater, in which previous methods (including standard PCR) failed to work. SIGNIFICANCE AND IMPACT OF THE STUDY: Cattle and dairy wastewater samples produced from mozzarella cheese factories may harbour verocytotoxin-producing E. coli. The availability of rapid and sensitive molecular methods may be useful to monitor the persistence of verocytotoxin-producing E. coli in general and to assess the effectiveness of wastewater treatments.

The cold dependent accumulation of COR TMC-AP3 in cereals with contrasting, frost tolerance is regulated by different mRNA expression and protein turnover.

The accumulation of specific cold-regulated (COR) proteins is a component of the hardening process and different amount of COR proteins has been related to different degrees of cold tolerance. A number of different mechanisms controls the accumulation of the COR proteins in the plant cells. In this work we describe the mechanisms controlling the accumulation of the COR protein TMC-AP3, a putative chloroplastic amino acid selective channel protein [1] in barley, durum, wheat, emmer and bread wheat. Winter barley and, to less extent, winter bread wheat showed a higher cor tmc-ap3 expression at low temperature than the spring one while no significant differences were detected between the emmer and the durum. wheat genotypes. After 2 days of de-hardening the transcript level dropped down in the same way in all tested genotypes, nevertheless the decrease in protein content was genotype dependent. In all frost resistant genotypes the amount of COR TMC-AP3 after 9 days of de-hardening was higher compared with that of susceptible ones. These findings suggest that resistant and susceptible genotypes have different protein degradation rate and/or mRNA translational efficiency. Differences in the protein degradation rate were not dependent from the amino acidic sequence of the protein, being extremely similar in all tested genotypes. A genetic study based on Chinese spring/Cheyenne chromosome substitution lines showed that the turnover of TMC-AP3 is a polygenic trait controlled by a number of loci being the most important located on chromosomes 1B, 2B, 2D and 4D.

Genetics of mutations affecting the development of a barley floral bract.

Two groups of mutants that affect the morphology of the lemma, a floral bract of barley, are described. The first comprises phenotypes associated with mutant alleles of calcaroides loci. On the lemma of these mutants, a well-organized neomorphic structure is formed, termed the sac. We provide a morphological description of wild-type (WT) and mutant lemmas, based on scanning electron microscopy (SEM), showing that both consist of similar tissues, but that the mutant is characterized by reversed growth polarity. The sac is a unique structure among grasses, and it is remarkable that recessive mutations at five different genetic loci lead to the same organ. The second group of mutants carry recessive alleles of two leafy lemma genes, both of which are necessary to cause the transformation of the lemma into a structure having all characteristics of a vegetative leaf, as shown by SEM analysis. The presence of sheath, blade, and ligule in the mutant lemma suggests that wild-type lemma development is interrupted at a leaf-like stage. The genes cal a, b, C, d, 23, lel1, and lel2 have now been mapped at precise positions on linkage groups 2, 7, 7, 3, 7, 5, and 7, respectively. The mutants considered in this article are unaffected in other floral organs. A model for lemma development is suggested.

Gastrointestinal symptoms in patients with asthma.

AIMS: Minor gastrointestinal abnormalities have been reported in children with asthma, but the prevalence of gastrointestinal symptoms in these children has not been studied. METHODS: 75 children with bronchial asthma and an age and sex matched control group were recruited. Parents completed a questionnaire on gastrointestinal symptoms and on asthma. Weight and height were measured; a clinical evaluation of asthma was undertaken and skin prick tests were performed. RESULTS: Children with asthma had a significantly greater frequency of gastrointestinal symptoms, particularly diarrhoea, vomiting, and abdominal pain, than did controls. Gastrointestinal symptoms were slightly more common in children with atopic symptoms other than asthma, or with positive skin prick tests to foods. There was no association between current gastrointestinal symptoms and medications or attacks of asthma. CONCLUSIONS: The occurrence of gastrointestinal symptoms appears to be common in children with asthma. These symptoms might be caused by an atopic gastroenteropathy, which might play a part in the pathogenesis of asthma in some cases.

An AFLP-based procedure for the efficient mapping of mutations and DNA probes in barley.

A strategy based upon AFLP markers for high-efficiency mapping of morphological mutations and DNA probes to linkage groups in barley is presented. First, 511 AFLP markers were placed on the linkage map derived from the cross Proctor x Nudinka. Second, loci controlling phenotypic traits were assigned to linkage groups by AFLP analysis, using F2 populations consisting of 30-50 mutant plants derived from crosses of the type "mutant x Proctor" and "mutant x Nudinka." To map DNA probes, 67 different wild-type barley lines were selected to generate F2 populations by crossing with Proctor and Nudinka. F2 plants that were polymorphic for a given RFLP fragment were classified into genotypic classes. Linkage of the RFLP polymorphism to 1 of the 511 AFLP loci was indicated by cosegregation. The use of the strategy is exemplified by the mapping of the mutation branched-5 to chromosome 2 and of the DNA probes Bkn2 and BM-7 to chromosomes 5 and 1, respectively. Map expansion and marker order in map regions with dense clustering of markers represented a particular problem. A discussion considering the effect of noncanonical recombinant products on these two parameters is provided.

Exercise-induced anaphylaxis related to cuttlefish intake.

UNLABELLED: A 14-year-old girl suffered from exercise-induced anaphylaxis associated with eating cuttlefish. She was advised to avoid the precipitating food 6 h before exercise. No further attack occurred. CONCLUSION: It should always be considered that foods can predispose exercise-induced anaphylaxis. Precipitating food should be identified by challenge test.

Food related, exercise induced anaphylaxis.

Four children under 12 years of age with food dependent, exercise induced anaphylaxis (EIAn) were investigated. These children and five controls performed exercise challenges when fasting and one hour after a meal without food suspected to predispose to the reaction. Patients then performed exercise tests after intake of each suspected food. Three out of 15 food-exercise combination challenges were positive, but no reactions were provoked after exercise without prior intake of suspected foods. Patients underwent skin prick tests to foods and serum total and specific IgE antibodies were measured. Skin prick test results were positive and RAST results were positive in two of three instances. In case 3, food-exercise combination challenges did not provoke any clinical reaction. The diagnosis of food dependent EIAn should be considered in young children with EIAn of unknown origin.

Quantitative resistance to barley leaf stripe (Pyrenophora graminea) is dominated by one major locus.

A major gene underlying quantitative resistance of barley against Pyrenophora graminea, a seedborne pathogen causing leaf stripe, was mapped with molecular markers in a barley doubled haploid (DH) population derived from the cross 'Proctor' x 'Nudinka'. This quantitative trait locus (QTL) accounts for r (2)= 58.5% and was mapped on barley chromosome 1, tightly linked to the "naked" gene. A second resistance QTL accounting for 29.3% of the variation in the trait was identified on the P arm of barley chromosome 2. Another two minor QTLs were detected by further analysis. None of the QTLs was found in the barley chromosome 2 "Vada" region studied by Giese et al. (1993).

RFLP analysis of highly polymorphic loci in barley.

Barley middle-repeat sequences were screened for their ability to discriminate 51 barley commercial varieties. Two hordein clones, a clone encoding a leaf-specific thionin, a desiccation induced cDNA clone, a clone coding for 5S-rRNA and one corresponding to ubiquitin genes were tested. A very sensitive RFLP technique including four cutter restriction enzymes and denaturing 4% polyacrylamide gels were used to evidence the highest level of polymorphism.The RFLP data were analyzed by computer. Some probe/enzyme combinations were able to differentiate a large number of the cultivars tested, whereas three probe/enzyme combinations succeeded in identifying all the varieties. The use of this RFLP method can thus be suggested for cultivar identification in barley.

Protein synthesis during cold shock in barley tissues : Comparison of two genotypes with winter and spring growth habit.

In barley (Hordeum vulgare L.) seedlings, a temperature step-down from 24 °C to 6°C (cold shock) determined a reduction in the incorporation of labeled aminoacids and modified the electrophoretic pattern of total proteins. At 6 °C some new proteins appeared and others were intensified (cold shock-induced proteins= CSPs); meantime, few proteins disappeared or were curtailed (cold-repressed proteins=CRPs). The majority of the proteins of the seedlings were labeled at about the same rate both at 6 °C and 24 °C, whereas at 0 °C only the cold shock proteins and a few others were detectable. The cold shock-induced variations of the protein profile differed in roots and in seed remnants which showed only some of the CSPs detected in roots. Total protein synthesis of barley genotypes 'Onice' and 'Georgie', which have respectively a winter and spring growth habit, were similarly inhibited by a temperature drop. The two genotypes, however, showed some differences in the CSPs and CRPs pattern. Because 'Onice' and 'Georgie' have also a different thermotolerance, the hypothesis can be made that in barley specific CSPs are involved in conferring various degrees of cold resistance.