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Many cultivars of European pears, treated with 1-methylcyclopropene (1-MCP), undergo a blockage of the ripening process that does not resume during shelf life. We evaluated the possibility to use different storage temperatures to prevent ripening blockage by 1-MCP and at the same time inhibit superficial scald. Early and optimal harvested ‘Abate Fetel’ pears were treated with 320 nl L-1 1-MCP for 24 h at 2°C. Subsequently the fruits were stored in air at -1 and 1°C for 17 and 34 weeks, respectively. All fruits treated with 1-MCP, depending on storage type and length, had lower ethylene production, compared with untreated controls. While treated fruits kept at 1°C were still firm at the end of storage and ripened normally to eating quality, softening and peel yellowing were prevented in fruit kept at -1°C. Superficial scald damaged the fruits kept at -1°C but not those stored at 1°C. 1-MCP treatment fully prevented scald. During storage the concentration of α-farnesene increased up to 17 weeks while conjugated trienols reached a peak after 34 weeks with large differences between -1 and 1°C. 1-MCP effectively reduced conjugated trienol accumulation at both storage temperatures. Results indicate the importance of raising the storage temperature from -1 to 1°C for reducing susceptibility to superficial scald, to avoid the ripening blockage by 1-MCP mainly in early picked fruit.

‘AbbA© FA©tel’ pears harvested at two maturity stages, were stored in regular controlled atmosphere (CA) (3 kPa O2 and 2 kPa CO2), ultra low-O2 (0.7 kPa O2 and 0.8 kPa CO2), dynamic controlled atmosphere (DCA) (0.4-0.7 kPa O2 and 0.8 kPa CO2) and conventional air storage. The fruit were kept in metal cabinets at -1°C and inspected after 90, 120 and 180 days. During storage, within each picking period, ethylene production by the fruit was in the following descending order, air storage > regular CA > Low-O2 > DCA. The reverse for flesh firmness and green colour of fruit skin. Overall fruit metabolism was markedly lower in the first picking during 6 months storage. Low-O2 and DCA prevented superficial scald development at the end of each storage period followed by shelf life. Air storage was characterized by a significant incidence of superficial scald that was reduced by regular CA. In these storage conditions a close relationship between superficial scald and increase of conjugated trienols during storage was detected, while a significantly lower content was found in Low-O2 and DCA. The lowest incidence of superficial scald was detected in the second picking. All fruit batches, except those stored in air storage, developed soft scald, a CA storage related disorder. Low-O2 and DCA promoted the highest incidence. At the end of shelf life all the fruit stored at the various conditions softened at different rates and fruit yellowing was sensibly delayed by low-O2 and DCA. No brown core disorder was detected.

Summary The fungal pathogen Colletotrichum acutatum is the causal agent of strawberry (Fragaria × ananassa) anthracnose. Although the fungus can infect strawberry fruits at both unripe and ripe stages, the symptoms appear only on red ripe fruits. On white unripe fruits, the pathogen becomes quiescent as melanized appressoria after 24 h of interaction. Previous transcriptome analysis has indicated that a mannose-binding lectin (MBL) gene is the most up-regulated gene in 24-h-infected white strawberries, suggesting a role for this gene in the low susceptibility of unripe stages. A time course analysis of the expression of this MBL gene, named FaMBL1 (Fragaria × ananassa MBL 1a), was undertaken to monitor its expression profile in white and red fruits at early interaction times: FaMBL1 was expressed exclusively in white fruit after 24 h, when the pathogen was quiescent. Agrobacterium-mediated transient transformation was used to silence and overexpress the FaMBL1 gene in 24-h-infected white and red strawberries, respectively. FaMBL1-silenced unripe fruits showed an increase in susceptibility to C. acutatum. These 24-h-infected tissues contained subcuticular hyphae, indicating pathogen penetration and active growth. In contrast, overexpression of FaMBL1 in ripe fruits decreased susceptibility; here, 24-h-infected tissues showed a high percentage of ungerminated appressoria, suggesting that the growth of the pathogen had slowed. These data suggest that FaMBL1 plays a crucial role in the resistance of unripe strawberry fruits to C. acutatum.

In recent years, safer methods for the control of fruit postharvest pathogens have been investigated and heat treatment could represent an effective and safe approach for managing postharvest decay such as Monilinia rots. In the present study, the effect of hot water treatment (HWT) (60 °C for 30 and 60 s) on brown rot was investigated. More specifically, the influence of HWT was determined in in vitro trials on conidial germination of Monilinia laxa, Monilinia fructicola and Monilinia fructigena and in peach and nectarine fruit, naturally infected. The effect of hot water application on fruit quality was also assessed. M. fructicola showed a greater resistance to heat than M. laxa and M. fructigena, however conidia germination of all three species was completely inhibited by a dipping in hot water for 1 min at 55 °C. The results of a large scale experiment under commercial conditions and several pilot trials showed a good antifungal activity of HWT in naturally infected fruit. After 6 days at 0 °C and 3 days at 20 °C, in both semi-commercial and commercial trials, the inhibition of decay was higher than 78% in four trials out of six. In addition, the treated fruit showed an acceptable commercial quality and no visual damage was observed as a consequence of HWT. The results demonstrated that HWT is a promising method to control Monilinia rots of peach and nectarine, and is safe and readily available for conventional and organic production under commercial conditions.

In search for alternative means to conventional fungicides for postharvest disease control, a Penicillium expansum strain (R82) was assayed for its inhibitory activity against mycelial growth and conidial germination of some fungal pathogens. For this purpose a sterile fungal filtrate (SFF) was prepared from malt extract broth previously inoculated with R82 and incubated at 20°C for 10 days. The SFF was tested in vitro for inhibition of mycelium dry weight (DMW) or conidial germination of Botrytis cinerea, Colletotricum acutatum, Monilinia laxa and six P. expansum strains. All pathogens showed a significant decrease of DWM when grown in SFF of R82 with respect to the control. The highest growth inhibition was observed in P. expansum strains (-75.5%) followed by M. laxa (-63%), C. acutatum (-58%) and B. cinerea (-56%). The conidial germination of the six P. expansum strains was not inhibited by SFF and in some cases was stimulated. In all tested strains, microscopic observations of germinated conidia showed a consistent increase of the length of the germ tube compared to the control, however, the treated germ tubes appeared to be abnormal. Since the thin-layer chromatography tests revealed that the extracts from R82 SFF have no inhibitory activity against the target pathogens, a possible action of volatile organic compounds (VOCs) was supposed. The VOCs produced by R82 strain fully inhibited mycelial growth of B. cinerea, C. acutatum and M. laxa, while a growth reduction occurred in P. expansum strains. Conidial germination of B. cinerea, C. acutatum and M. laxa were completely inhibited, while in P. expansum ranged 18.1 to 32%, compared to the control. The potential of VOCs produced by P. expansum R82 strain as biofumigant is discussed.

Ppdfn1 is a defensin gene previously identified in peach (Prunus persica). The biological role of Ppdfn1 was investigated by analysing its expression profile in leaves, flowers and fruits, either inoculated with the Monilinia laxa fungal pathogen or mock-inoculated. Ppdfn1 expression was highest in flowers and, in fruits, did not vary upon M. laxa inoculation. To characterize the PpDFN1 antifungal activity, the recombinant mature peptide was expressed in Escherichia coli and purified; recombinant PpDFN1 displays antifungal activity against Botrytis cinerea, M. laxa and Penicillium expansum, with IC50 values of 15·1, 9·9 and 1·1 μg mL−1, respectively. Treatment of fungal hyphae with FITC-labelled PpDFN1 indicated that the peptide is not internalized by fungal hyphae, but localizes on their external cell surface. At this site, PpDFN1 is capable of membrane destabilization and permeabilization, as demonstrated by SYTOX Green fluorescence uptake by the treated mycelia. Using artificial lipid monolayers, it was shown that PpDFN1 interacts with sphingolipid-containing membranes; however the strongest interaction occurs with monolayers composed of lipids extracted from sensitive fungi, such as P. expansum. These data suggest that the lipid composition of fungal membranes is of key relevance for defensin specificity.

Microscopic investigations were conducted into the interaction of Colletotrichum acutatum on white and red strawberry (Fragaria ×ananassa) fruit surfaces. The results showed that, whilst the early interaction events were similar in both white and red fruits, after 24 h fungal colonization dramatically varied: in white fruits C. acutatum became quiescent as melanized appressoria, but on red fruits it displayed subcuticular necrotrophic invasion. A microarray analysis of white and red strawberries after 24 h of interaction with C. acutatum was performed, in order to reveal differences in gene expression possibly related to the different susceptibility of unripe and ripe fruits. Epi/catechin-related genes and fatty acid metabolism genes, involved in the production of quiescence-related molecules such as flavan-3-ols, proanthocyanidins and antifungal dienes, were found to be regulated during strawberry ripening, supporting a role for these molecules as preformed defence mechanisms. Besides several genes commonly regulated upon pathogen interaction, different genes were specifically transcribed only in white or red challenged fruits; a number of these, such as those coding for lectin and polyphenol oxidase, possibly account for specific pathogen-induced responses. The putative biological role of these genes in the different susceptibility of fruits to C. acutatum is discussed.

PR-10 proteins are a family of pathogenesis-related (PR) allergenic proteins playing multifunctional roles. The peach (Prunus persica) major allergen, Pru p 1.01, and its isoform, Pru p 1.06D, were found highly expressed in the fruit skin at the pit hardening stage, when fruits transiently lose their susceptibility to the fungal pathogen Monilinia spp. To investigate the possible role of the two Pru p 1 isoforms in plant defense, the recombinant proteins were expressed in Escherichia coli and purified. Light scattering experiments and circular dichroism spectroscopy showed that both proteins are monomers in solution with secondary structures typical of PR-10 proteins. Even though the proteins do not display direct antimicrobial activity, they both act as RNases, a function possibly related to defense. The RNase activity is different for the two proteins, and only that of Pru p 1.01 is affected in the presence of the cytokinin zeatin, suggesting a physiological correlation between Pru p 1.01 ligand binding and enzymatic activity. The binding of zeatin to Pru p 1.01 was evaluated using isothermal titration calorimetry, which provided information on the stoichiometry and on the thermodynamic parameters of the interaction. The structural architecture of Pru p 1.01 and Pru p 1.06D was obtained by homology modeling, and the differences in the binding pockets, possibly accounting for the observed difference in binding activity, were evaluated.

Colletotrichum acutatum , a fungal pathogen that causes soft rot in fruit, produced polygalacturonases (PGs) when grown on pectin or apple wall polysaccharides, as revealed by a clear zone around the well filled with C. acutatum medium in a radial diffusion assay. A PG-inhibiting protein (PGIP) was also extracted from healthy stored ‘Cripps Pink’ apple and its activity was tested in vitro and in vivo against an endo-PG (EC 3.2.1.15) of C. acutatum . In i n vitro trials the inhibition determined by radial diffusion assay was over 62% after 24 h while in inoculated fruit the inhibition ranged from 33.9% to 54.4% after 4 days at 20 °C. The PG inhibitor extracted from healthy skin apple was a heat-denaturable protein since the halo produced by protein extracted from C. acutatum and added to boiled protein extracted from healthy skin apple tissue was 246 mm 2 , significantly higher than the halo produced by protein extracted from C. acutatum diluted with fresh protein extracted from healthy tissue (93.6 mm 2 ). More investigations are required to better understand the nature of the substance responsible for C. acutatum inhibition in apple and to evaluate the possibility of manipulating the PGIP levels in fruit to reduce soft rot caused by C. acutatum .

Monilinia brown rot is one of the most important diseases of peach (Prunus persica L. Batsch). In this study, the susceptibility to Monilinia rot of peach fruit during ripening was analysed weekly by assessing infected fruits upon artificial inoculation. Fruit drastically reduced their susceptibility to Monilinia rot along with ripening, becoming resistant in correspondence to pit hardening (a two-week period). Susceptibility increases again thereafter. With the aim to identify genes possibly correlated with the variation of brown rot susceptibility, a microarray based-transcriptome analysis was undertaken to compare the expression of genes between susceptible fruit (two weeks before the pit hardening stage) and resistant fruit (at the pit hardening stage). This approach pointed out that genes involved in defence and primary and secondary metabolism, in particular some phenylpropanoid and flavonoid related genes, are differentially expressed in susceptible and resistant fruit. Considering that several aromatic compounds with antifungal properties are known to accumulate during endocarp lignification, the expression levels of genes encoding key enzymes of the phenylpropanoid and jasmonate pathways was quantified by real time RT-PCR in the peel of both susceptible and resistant fruit. Results show that during the two-week time between the susceptible and resistant fruit stages the expression of several genes involved in the synthesis of phenylpropanoid and jasmonate compounds drastically changes, supporting a role for these metabolites in the fruit response to Monilinia.

Strawberry (Fragaria × ananassa) fruit contains high concentrations of health-promoting phenolic compounds, playing important roles for the fruit ontogenic tolerance to fungi. In the highly susceptible cultivar Alba, the two major strawberry fungal pathogens, Colletotrichum acutatum and Botrytis cinerea, displayed disease symptoms only at red ripe stages because immature fruits are tolerant to diseases. We analyzed and compared the variation of 47 polyphenols in the surface of unripe and ripe Alba fruits upon 24 and 48 h of C. acutatum and B. cinerea infection or mock inoculation. Significant alteration in phenolic content was detected only in white infected fruit, with differences specific for each pathogen. The expression analysis of phenylpropanoid, flavonoid, and shikimate pathway genes showed in only a few cases correlation with the relative metabolite abundance. The alteration in phenolic content and the lack of consistency with gene expression data are discussed in light of previously reported metabolome data of different susceptible and resistant strawberry genotypes.

Nine plant-volatile compounds were tested for their activity against Monilinia laxa, the cause of brown rot in stone fruit. In vitro trials on conidial germination and mycelial growth showed a consistent fungicidal activity of trans-2-hexenal, carvacrol, and citral, whereas trans-cinnamaldehyde, hexanal, (-)-carvone, eugenol, 2-nonanone, and p-anisaldehyde exhibited a progressively lower inhibition. The best inhibitor of conidial germination was trans-2-hexenal (effective dose for 50 and 90% inhibition [ED50 and ED95] = 7.53 and 9.4 μl/liter, respectively; minimal inhibitory concentration [MIC] = 12.3 μl/liter], whereas carvacrol was the best inhibitor of mycelial growth (ED50 and ED95 = 2 and 3.4 μl/liter, respectively; MIC = 6.1 μl/liter). The three most active compounds in in vitro studies also were tested in vivo as postharvest biofumigants. The best control of brown rot was with trans-2-hexenal (efficacy ranging from 46.2 to 80.3%, depending on cultivar), whereas citral and carvacrol resulted in a lower efficacy of 40 and 32.9%, respectively. Fumigation with trans-2-hexenal at concentrations that stopped decay did not cause any visible disorders to plum, whereas it was phytotoxic to apricot, peach, and nectarine and produced off-odors or off-flavors in all species of stone fruit tested.

The effects of trans -2-hexenal vapour treatment on Penicillium expansum , patulin content and fruit quality were evaluated in several cultivars of pears (“Abate Fetel”, “Bartlett” and “Kaiser”) and apples (“Golden Delicious” and “Royal Gala”). Fruit, wound-inoculated or non-inoculated, were treated at 20 °C with different concentrations of trans -2-hexenal over a 24 h period. Blue mould control, ranging from 50 to 98% (depending on cv), and reduction of patulin content were achieved when fruit were exposed to vapours from 12.5 μL L −1 of trans -2-hexenal 24 h after pathogen inoculation. In contrast, treatments applied 2 h after inoculation exhibited less efficacy or stimulated P. expansum infections. Trans -2-hexenal (12.5 μL L −1 ) did not affect fruit appearance, colour, firmness, soluble solids content or titratable acidity. Only in “Abate Fetel” pears phytotoxic symptoms developed within 3 days of treatment. Off-odours developed just after treatment, but the intensity decreased or disappeared during shelf-life. After 7 days at 20 °C following treatment (12.5 μL L −1 ) no significant differences in trans -2-hexenal content or in sensory traits were detected by a trained panel between untreated and treated “Golden Delicious” apples, while maintenance of off-flavours was perceived in “Bartlett”, “Abate Fetel” and “Royal Gala” fruit.

The effects of CO 2 -enriched atmospheres on the infections of Botrytis cinerea in red chicory (Cichorium intybus L. var. silvestre Bischoff) cv. 'Radicchio rosso di Chioggia' were studied during storage at 0°C up to 150 days. B cinerea growth, conidial germination and sclerotial production were evaluated also in vitro. Mycelial growth on PDA decreased linearly as CO 2 concentrations increased from 5, 10, 15 and 20%. A reduced production of sclerotia in air, by the colonies formerly exposed to various CO 2 concentrations, was also detected. Conidial germination and germ tube elongation was delayed with increased CO 2 and inhibited at 20% CO 2 . In artificially inoculated heads, lesion area caused by B. cinerea decreased with increasing concentrations of CO 2 up to 60 days of storage; later only 10 and 15% CO 2 were really effective, while after 120 days all the concentration tested showed a low efficacy. In naturally infected heads the effect of 5 and 10% CO 2 was remarkable even after 150 days of storage as it was prevented not only the growth of B. cinerea in each single head but also the disease spread to adjacent plant (nesting), thus reducing the overall losses. Phytotoxic effects combined with a higher vulnerability to rots were detected in heads kept at 15% CO 2 for 150 days.

Reactive oxygen species (ROS) are dangerous molecules because they can cause damage to proteins, lipids and nucleic acids. ROS production in plants increases at low temperatures; particularly sub-tropical species are sensitive to ROS when they are exposed to temperatures below 10°C. To prevent damage from ROS and to scavenge them, plants developed an enzymatic and a non-enzymatic antioxidant system. The enzymatic antioxidant system was studied in this work during the post-harvest cold storage of aubergine using the real time PCR technique in order to monitor changes in the transcript level of genes encoding for ROS scavenging enzymes. Changes in Mn Superoxide-dismutase, Catalase, Glutathione reductase, Ascorbate peroxidase gene expression were analyzed during storage at 0°C and at 10°C up to 10 days. Catalase gene expression is stimulated during storage at 10°C and inhibited at 0°C. Equally, Glutathione reductase gene expression is upregulated in this milder refrigeration condition. On the contrary Mn-superoxide dismutase and Ascorbate peroxidase transcript levels decrease with respect to the initial amount for both temperatures. This suggests that oxidative stress can cause damage during cold storage of aubergine. The expression of ROS scavenging enzymes is positively regulated during the 10°C cold storage contrary to the 0°C cold storage, indicating the presence of oxidative stress and a tissue reaction.

Left ventricular (LV) filling deceleration time (DT) is determined by the sum of atrial and ventricular stiffnesses ( KLA+ KLV). If KLA, however, is close to zero, then DT would reflect KLVonly. The purpose of this study was to quantify KLAduring DT. In 15 patients, KLVwas assessed, immediately after cardiopulmonary bypass, from E wave DT as derived from mitral tracings obtained by transesophageal echocardiography and computed according to a validated formula. In each patient, a left atrial (LA) volume curve was also obtained combining mitral and pulmonary vein (PV) cumulative flow plus LA volume measured at end diastole. Time-adjusted LA pressure was measured simultaneously with Doppler data in all patients. KLAwas then calculated during the ascending limb of the V loop and during DT. LA volume decreased by 7.3 ± 6.5 ml/m2during the first of mitral DT, whereas LV volume increased 9.4 ± 8.4 ml/m2(both P < 0.001). There was a small amount of blood coming from the PV during the same time interval, with the cumulative flow averaging 3.2 ± 2.4 ml/m2( P < 0.001). Mean LA pressure was 10.0 ± 5.1 mmHg, and it did not change during DT [from 7.8 ± 4.3 to 8.0 ± 4.3 mmHg, not significant (NS)], making KLA, which averaged 0.46 ± 0.39 mmHg/ml during the V loop, close to zero during DT [ KLA(DT): from −0.002 ± 0.08 to −0.001 ± 0.031 mmHg/ml, NS]. KLV, as assessed noninvasively from DT, averaged 0.25 ± 0.32 mmHg/ml. In conclusion, notwithstanding the significant decrement in LA volume, KLAdoes not change and can be considered not different from zero during DT. Thus KLAdoes not affect the estimation of KLVfrom Doppler parameters.

Apricot and peach fruit were harvested weekly for 2 years, beginning 4 weeks after full bloom until commercial maturity. Wounded and unwounded fruit were inoculated with Monilinia laxa at 10 5 conidia ml −1 . Fruit were characterized by dry matter (%) and stage of pit hardening, and brown rot incidence was evaluated after 7 days at 20 °C. Results show three stages of different susceptibility to M. laxa infection for both apricots and peaches. In the first stage susceptibility were high, but decreased in the second stage (rest period) during which the pit hardening occurred and green fruit were also resistant to the high inoculum concentration. Finally, in the third stage, from 4 to 5 weeks before full ripeness, fruit increased their susceptibility to M. laxa . Wounded and unwounded fruit showed the same susceptibility to the pathogen during growth. In peaches, dry matter was negatively correlated with Monilinia rot incidence.

Isolates of Penicillium expansum recovered from stored pears were scored for resistance to the fungicide thiabendazole (TBZ) and for pathogenic fitness. Out of 50 isolates, nine were sensitive (S) and 41 resistant (R or RR). Seven of these resistant isolates (RR) germinated with a higher percentage on TBZ-amended medium than on unamended medium. Six S isolates and six RR isolates were chosen at random for further analysis. S and RR isolates had similar in vitro growth fitness, although RR isolates were characterized by higher infection severity on fruits. Laboratory-induced resistant isolates were generated by UV-irradiating S strains, and a similar correlation between the induced TBZ resistance and pathogenic fitness was observed. The β-tubulin gene of RR and S isolates was amplified and sequenced; mutations correlating with TBZ resistance were identified at residues Phe 167 and Glu 198. Analogous mutations were detected in the laboratory-induced resistant isolates.

Pears are highly perishable products, especially during the post-harvest phase, when considerable losses can occur. Among the fungal diseases, blue mold caused by Penicillium expansum, grey mould caused by Botrytis cinerea, Mucor rot caused by Mucor piriformis are common on pear fruits. Other (weak) pathogens like Phialophora malorum, Alternaria spp., and Cladosporium herbarum tend to infect wounds and senescent fruits. A post-harvest fungicide treatment can reduce decay but effectiveness decreases with the appearance of resistant strains. There is a clear need to develop new and alternative methods of controlling post-harvest diseases. The emerging technologies for the control of post-harvest fungal diseases are essentially threefold: application of antagonistic microorganisms, application of natural antimicrobial substances and application of sanitizing products. Two biological control products, Aspire (Candida oleophila I-182) (Ecogen, Langhorne, PA, USA) and Bio-Save 110 (Pseudomonas syringae) (EcoScience, Worcester, MA, USA; formerly Bio-Save 11) are currently registered in the USA for post-harvest application to pears. Other potential biocontrol agents have been isolated from fruit and shown to suppress post-harvest decay in pear. It is important that evaluation of these microorganisms be carried out in a product formulation because the formulation may improve or diminish antagonistic efficacy depending on the concentration of chemical product and the duration of exposure to the treatment. Plants produce a large number of secondary metabolites with antimicrobial effects on post-harvest pathogens. Detailed studies have been conducted on aromatic compounds, essential oils, volatile substances and isothiocyanates, with encouraging results. In particular, allyl-isothiocyanate used as a volatile substance, controls blue mould in 'Conference' and 'Kaiser' pear inoculated with a thiabendazole-resistant strain. Sanitizing products such as chlorine dioxide, peracetic acid and ozone have considerable fungicidal activity against P. expansum and M. piriformis, depending on the concentration of chemical product and the duration of exposure to the treatment. Sanitizing solutions can be integrated easily with current handling and storage practices; however, further research is required to define the effective procedures better.

The effects on Botrytis cinerea of prolonged exposures to CO 2 -enriched atmospheres were studied in vitro and in vivo at 0°C. Mycelial growth on potato dextrose agar decreased linearly with increasing CO 2 concentrations from 5, 10, 15 and 20% CO 2 . The growth reduction was greater after 30-40 days of incubation. A reduced production of sclerotia in air by the colonies formerly exposed to various CO 2 concentrations was also detected. Conidial germination was delayed and the amount of germinated conidia decreased with increased CO 2 and at 20% CO 2 it was inhibited. Germ tube elongation was affected in the same way. In artificially inoculated red chicory, lesion area caused by B. cinerea decreased with increasing concentrations of CO 2 up to 60 days storage, later only 10 and 15% CO 2 were really effective, while in the final inspection after 120 days all the concentration tested showed a low efficacy. Similar results were obtained in naturally infected chicory where the severity of the disease decreased by increasing CO 2 from 5 to 10%, higher values did not improve the suppressive effect or determined, after 150 days of storage, an increased vulnerability of the tissues to disease due to the phytotoxic effects of the gas. An atmosphere enriched with 10% CO 2 is advised to suppress Botrytis rot during storage at 0°C of red chicory.

Ninety isolates of Botrytis cinerea collected from kiwi fruit in orchards and in cold storage were compared phenotypically and genetically. The phenotypic characters evaluated were conidia germination, germ tube length and mycelial growth at 0 � and 20 � C. At 20 � C the two populations showed slight differences but, at 0 � C, isolates from cold storage appeared to grow significantly faster than isolates from orchards. Isolates were then scored with six genetic markers with the aim of investigating population, genetic structure and the mode of reproduction. We detected no genetic differentiation between isolates from orchards and those from cold storage. This suggests that low temperature adaptation of B. cinerea isolates does not have a genetic basis. By contrast, we found great intra-population genetic diversity, observations suggesting the occurrence of genetic recombination which follows sexual reproduction or alternatively of parasexuality.

The fungal pathogen Colletotrichum acutatum is the causal agent of strawberry (Fragaria × ananassa) anthracnose. Although the fungus can infect strawberry fruits at both unripe and ripe stages, the symptoms appear only on red ripe fruits. On white unripe fruits, the pathogen becomes quiescent as melanized appressoria after 24 h of interaction. Previous transcriptome analysis has indicated that a mannose‐binding lectin (MBL) gene is the most up‐regulated gene in 24‐h‐infected white strawberries, suggesting a role for this gene in the low susceptibility of unripe stages. A time course analysis of the expression of this MBL gene, named FaMBL1 (Fragaria × ananassa MBL 1a), was undertaken to monitor its expression profile in white and red fruits at early interaction times: FaMBL1 was expressed exclusively in white fruit after 24 h, when the pathogen was quiescent. Agrobacterium‐mediated transient transformation was used to silence and overexpress the FaMBL1 gene in 24‐h‐infected white and red strawberries, respectively. FaMBL1‐silenced unripe fruits showed an increase in susceptibility to C. acutatum. These 24‐h‐infected tissues contained subcuticular hyphae, indicating pathogen penetration and active growth. In contrast, overexpression of FaMBL1 in ripe fruits decreased susceptibility; here, 24‐h‐infected tissues showed a high percentage of ungerminated appressoria, suggesting that the growth of the pathogen had slowed. These data suggest that FaMBL1 plays a crucial role in the resistance of unripe strawberry fruits to C. acutatum.

The content of chlorogenic acid, (+)-catechin, (-)-epicatechin, phloretin glycosides, and quercetin glycosides in fresh and stored Golden Delicious apples (Malus domestica Borkh) was determined. The relative amount of phenolics in the peel, with the exception of chlorogenic acid and (-)-epicatechin, was higher than that in the flesh. In addition, quercetin glycosides were detected only in the skin. These compounds were tested for fungicidal activity against Phlyctaena vagabunda Desm., the causal agent of a postharvest rot. Chlorogenic acid only inhibited P. vagabunda spore germination and mycelial growth in vitro. Changes of apple phenolics and polyphenol oxidase activity during cold storage and the biological activity of these phenolics have also been analyzed with reference to the development of quiescent infections during cold storage plus shelf life at room temperature. The results obtained suggested that phloridzin and chlorogenic acid in combination with polyphenol oxidase activity could function to arrest P. vagabunda in quiescent infections associated with immature and ripening apple fruit.

Background . To define the long-term results of 331 standard Hancock porcine bioprostheses implanted in the mitral position between 1973 and 1980. Methods . Of 331 patients (225 male patients, 68%), mean age 49 ± 10 years (range 14 to 69 years), 88% were in New York Heart Association functional class III or IV and 77% were in atrial fibrillation. Follow-up time extended more than 20 years (mean 13.9 years, range 0.3 to 24.7 years) for a total of 4,601 patient-years. Results . Overall operative mortality was 6.3%. At 5, 10, 15, and 20 years, the actuarial survival rate of patients were 71% ± 2%, 46% ± 3%, 30% ± 3%, and 22% ± 2%, respectively. Actuarial estimates of freedom from structural valve deterioration were 95% ± 1%, 67% ± 3%, 32% ± 3%, and 14% ± 3%; from reoperation were 96% ± 1%, 72% ± 3%, 36% ± 4%, and 18% ± 4%; from thromboembolism were 89% ± 2%, 82% ± 3%, 74% ± 4%, and 51% ± 2%; and from anticoagulant-related hemorrhage were 98% ± 1%, 96% ± 1%, 91% ± 1%, and 86% ± 4%. Estimates of freedom from all valve-related mortality at 5, 10, 15, and 20 years were 89% ± 2%, 76% ± 3%, 64% ± 4%, and 48% ± 4%. Multivariate analysis showed younger age to be a significant risk factor for reoperation. Age at operation did not correlate with structural valve deterioration. Conclusions . The long-term results with the standard Hancock bioprosthesis implanted in the mitral position appear satisfactory, particularly up to 15 years from implantation. Protection from stroke, anticoagulant hemorrhage, and endocarditis was good.

Background . Stentless xenografts have been proposed as substitutes for the diseased aortic valve. Cases of valve failure requiring reoperation have thus far been sporadic. To establish the prevalence and outcome of reoperation on stentless aortic xenograft valves, all patients operated on between October 1992 and October 1996 were reviewed. Methods . One hundred ninety-nine patients, 94 men and 105 women aged 70 ± 7 years, had stentless aortic valve replacement for aortic stenosis (in 139), insufficiency (19), or both (38). Three prostheses were used, including the Biocor PSB (Belo Horizonte, Brazil) (106), Toronto SPV (St. Jude Medical, Inc., St. Paul, MN) (52), and O'Brien-Angell (Cryolife, Atlanta, GA) (41). While the Biocor PSB and Toronto SPV prostheses are designed to be implanted freehand with inflow and outflow suture lines, the O'Brien-Angell valve requires a single suture line. Results . There were 7 (3.5%) total and 6 (3%) valve-related reoperative procedures during a follow-up extending up to 4 years (mean 26 ± 20 months). All but one valve-related reoperation, due to endocarditis 36 months after implant, were early (less than 12 months after initial operation). Prevalence of valve-related reinterventions was 1%, 0%, and 12%, and freedom from reoperation at 3 years was 98% ± 2%, 100%, and 81% ± 8%, in patients receiving the Biocor PSB, Toronto SPV, and O'Brien-Angell valves, respectively ( p = 0.0039). Cause of reoperation was technical in 3 (O'Brien-Angell), pannus ingrowth in 1 (O'Brien-Angell), valve tear in 1 (O'Brien-Angell), and endocarditis in 1 (Biocor PSB). All patients survived replacement of the xenograft with a stented bioprosthesis (5) or homograft root (1) and were discharged after a mean hospital stay of 6 ± 3 days (range, 4 to 12 days). At follow-up 15 ± 8 months after reintervention (range, 6 to 34 months), all patients are symptom-free with no evidence of recurrent valve obstruction, regurgitation, or infection. Conclusions . Reoperation for stentless xenograft failure is a rare overall event. Implant of the O'Brien-Angell valve may be associated with a higher prevalence of early reintervention because of nonstructural failure. When needed, reoperation on a stentless xenograft is generally a simple procedure and carries a low surgical risk.

Objective: To test the hypothesis of an improved myocardial and cerebral protection by combining blood cardioplegia and the single aortic cross-clamp technique, 100 patients were enrolled in a prospectively randomized study and stratified for preoperative conditions. Methods: In Group I, 55 patients underwent myocardial revascularization using crystalloid cardioplegia and the conventional partial occluding clamp technique to perform proximal anastomoses, whereas in Group II, 45 patients were operated on combining blood cardioplegia and the single aortic cross-clamp technique. Unstable angina, emergency procedures, reoperations and preoperative counterpulsation accounted for an higher risk score in group II patients (P< 0.03). Operations were performed by the same surgical team. Aortic cross-clamp time was significantly longer in group II patients (59 ± 22 vs. 47 ± 18 min.) (P

Botrytis allii colonies incubated at low temperatures have been reported to produce larger conidia that germinate faster and give rise to longer germ-tubes than those grown at room temperature. The present study compared the effect of conidia produced at 20°C and at 0 and -2°C on their pathogenicity to artificially inoculated white onion bulbs, and the effect of conidial concentration (5 x 10 3 and 5 x 10 4 conidia/mL) on disease incidence, lesion area, incubation and latent period during storage at 20, 5 and 0°C. At all storage temperatures and periods tested conidia produced at -2°C caused a higher disease incidence and larger areas of rot than those produced at higher temperatures. When the conidial production temperature was raised to 20°C, the duration of incubation on the bulbs inoculated with 5 x 10 4 conidia/mL was more than doubled during storage at 0°C, tripled at 5°C, and took 50% longer at 20°C. The incubation period was not significantly affected by conidial concentration at 20°C, and only slightly at 5 and 0°C, but at low temperatures the latent period was longer because of the delay induced in sporulation. These data are consistent with the packers' opinion that cross-infection of spring onions by long-term refrigerated onions in grading lines caused earlier and heavier rotting.

Penicillium hirsutum grown on potato dextrose agar and kept at 20, 10, 4, 2, 0, −2 and −4 °C for 25 weeks revealed a longer lag phase at 0 °C and below, and its growth was reduced as the temperature was lowered. At −4 °C, the fungus showed slight lengthening of the hyphae only after 19 weeks. Sporulation and germination of conidia were also delayed by low temperatures, and at −4 °C there was no production or germination. All of the wounded and inoculated cloves of ‘Bianco Piacentino’ garlic showed symptoms of blue mould disease after four weeks of storage at temperatures between 0 and 20 °C. At −2 °C, P. hirsutum colonised all of the cloves after seven weeks, while at −4 °C they were all still healthy after 16 weeks. No freezing injury was encountered at negative temperatures. A storage temperature of −4 °C is advisable for the prevention of blue mould disease.

Botrytis allii was incubated at 20, 10, 4, 2, 0, -2 and -4° to investigate effects of temperature on growth, sporulation and germination on potato dextrose agar (PDA), and to estimate incidence and severity of disease on garlic bulbs inoculated with the pathogen during storage. B. allii was capable of growing to a colony diameter of 17 mm after 20 weeks, sporulating and germinating on PDA at temperature as low as -4°C. After 12 weeks at -4 and -2°C the mycelial growth was observed only on 45-54% of bulbs wound-inoculated with conidial suspension, and infection was limited to 5 mm in diameter on the surface of inoculation sites without producing any symptoms of the disease. Temperature responses were similar for mycelial growth, conidial germination and infection, but mycelial growth and sporulation was slower and later on garlic bulbs than in culture. Wounds were readily colonized by B. allii. No disease was found on unwounded bulbs that were inoculated with conidial suspensions and with mycelial plugs at various temperatures. Only 1.6-9.5% of cloves became infected by contact with other cloves within the same bulb after 12 weeks of storage at temperatures of 4-20°C.

The activity of two biological control agents, strains L1 and L8, previously identified as Aureobasidium pullulans, was tested for the first time in the same experiments on apple, artificially inoculated with Botrytis cinerea (grey mould), Colletotrichum acutatum (bitter rot) or Penicillium expansum (blue mould). The washed cells of antagonists controlled over 86% of three decays and the antagonist L1 seemed more efficient than L8. The cell concentration of both antagonists was highly correlated with their efficacy, the R2 ranging from 0.93 to 0.99. The highest concentration (108 CFU ml-1) of L1 and L8 provided the best control of B. cinerea, C. acutatum and P. expansum, although gray mould was completely inhibited also by a concentration one log lower (107 CFU ml-1). The population dynamic of L1 and L8 strains in ‘Gala’ apple increased almost eightfold during the first 48 h after treatment and remained elevated until 7 days, revealing that, although antagonists were isolated from carposhere of peach fruit, they showed good adaptation in other wound environments such as apple, making them suitable for pathogen control in a wide range of hosts. Preliminary in vitro trials were conducted in order to investigate the mechanisms of action of L1 and L8 strains. Both the washed cells showed a complete control of all three pathogens, while the culture filtrates and autoclaved cells were found to have had no significant inhibition on pathogens. In a dual culture dish assay, where there was neither physical contact between antagonists and pathogens nor fungal diffusion through the culture medium, the antifungal effects observed on pathogen mycelium growth could be attributed to the production of volatile organic compounds (VOCs) generated by the antagonists. The VOCs significantly inhibited the growth of all three tested pathogens compared to the control, albeit with a different rate. L1 strain also showed a curative effect; indeed when an antagonist-based-treatment was carried out twelve hours from inoculum, the incidence of blue mould and bitter rot was reduced by 38% and 50% respectively, while the greatest inhibition of grey mould was observed when fruit were treated with the antagonist six hours from the inoculum. In conclusion, A. pullulans L1 and L8 strains could be considered good candidates for the development of biofungicides for postharvest application in the pomefruit industry.

Primary pulmonary trunk sarcoma is a rare and highly lethal disease. A case of multicentric pulmonary trunk leiomyosarcoma with right and left main pulmonary artery involvement, mimicking massive pulmonary embolism, is described. The importance of a timely diagnosis and of radical surgical excision is discussed.

Background Chronic obstructive pulmonary disease is a risk factor for postoperative lung injury. Contradictory results have been published about leukocyte filtration (LF) because of the heterogeneity of patients and interventions, type of LF, and comorbidities. Methods Sixty patients with mild moderate chronic obstructive pulmonary disease (forced expiratory volume in 1 second 40% to 80%) undergoing aortic valve surgery were randomly assigned to receive systemic arterial and cardioplegic LF during cardiopulmonary bypass (group L, 30 patients) or standard cardiopulmonary bypass (group S). Perioperative interleukin-6, interleukin-8, and tumor necrosis factor-alpha were sampled at different time points. The PaO 2 /inspired oxygen fraction (FiO 2 ) and alveoloarterial oxygen gradient (AaDO 2 ) were measured preoperatively, at intensive care unit arrival, and at 24, 48, and 72 hours postoperatively; lung compliance was measured after intubation, at intensive care unit arrival, and at 4 and 8 hours postoperatively; and radiographic lung injury score was determined preoperatively and at 24, 48 and 72 hours. Length of intubation, intensive care unit stay, hospital stay, need for noninvasive positive-pressure ventilation, acute lung injury, and pneumonia were recorded. Repeated-measures analysis of variance assessed group, time, and group by-time interactions. Results Preoperative and intraoperative data were comparable. Proinflammatory cytokine leakage was reduced by LF. Group L showed shorter intubation time (median 9.5 hours versus group S, 15.0 hours; p = 0.0001), and intensive care unit length of stay (median 19.0 hours versus group S, 24.5; p = 0.0001), lower need for noninvasive positive-pressure ventilation (5 of 30, 16.7%, versus 12 of 30, 40%; p = 0.042). The AaDO 2 , PaO 2 /FiO 2 , lung compliance, and radiographic lung injury score worsened early postoperatively, followed by progressive improvements (time p ≤ 0.001 for all). Such decline of AaDO 2 , PaO 2 /FiO 2 , lung compliance, and radiographic lung injury score was significantly attenuated by LF (group by-time p = 0.0001 for AaDO 2 , PaO 2 /FiO 2 , and lung compliance; p = 0.004 for radiographic lung injury score). Conclusions Arterial plus cardioplegic LF significantly reduced proinflammatory cytokine release after cardiopulmonary bypass, thus ameliorating postoperative indexes of lung function and overall respiratory outcome.

Penicillium expansum causing blue mould is a serious postharvest pathogen in all growing pome fruit areas. Physical treatments, including storage atmosphere manipulation, have been developed to control postharvest fungal decay. The present study aimed to determine the influence of oxygen (O 2 ) levels on growth of P. expansum (P37 strain). Pathogen enzymatic production at low oxygen levels was also tested in in vitro trials by agarose diffusion assay. In in vitro trials, 100 μl of conidial suspension (10 3 conidia per ml) was spread on MEA dishes, stored for 30 days at 0°C with 0.7, 1.5, 3, 6 and 21% O 2 . The concentration of carbon dioxide was 1%. In in vivo trials, fruit were wounded and inoculated with 20 μl of a conidial suspension (10 3 conidia per ml) of P. expansum and stored with the same oxygen concentrations for five months at 0°C plus 3 days at 20°C. No significant differences were observed, within the different oxygen concentrations, on P. expansum growth in vitro. The percentage of infected fruit was significantly greater at low oxygen concentrations (0.7, 1.5, 3%) than at 6 or 21%. However, the dimensions of decay lesions, on apples exposed to 21 and 6% of O 2 , were significantly larger than those of apples stored at 0.7, 1.5 and 3% O 2 . In addition, O 2 levels greatly influenced the enzymatic activity. Polygalacturonase, protease and amylase activities were increased by low oxygen level (0.7%), whereas cellulases were reduced by the same oxygen concentration. More investigations are required to better elucidate the interactions between pathogen-fruit-oxygen level and the role of the enzymes in pathogenicity.

Fumigation by plant volatile compounds and hot water treatment were tested in vitro and in vivo for their activity against Neofabraea alba (anamorph Phlyctema vagabunda ), the cause of lenticel rot in apple fruit. In vitro trials with volatile compounds showed a consistent inhibition of pathogen growth by carvacrol, trans -cinnamaldehyde, citral and trans -2-hexenal, while (−)-carvone, hexanal, p -anisaldehyde, 2-nonanone and eugenol showed progressively lower inhibition. The greatest inhibition of mycelial growth was demonstrated by carvacrol (effective doses for 50 and 95 inhibition [ED 50 and ED 95 ] = 5.9 and 17.0 μL L −1 , respectively; minimum inhibitory concentration [MIC] = 36.9 μL L −1 ) and of conidial germination by trans -2-hexenal (ED 50 and ED 95 = 4.1 and 6.9 μL L −1 , respectively; MIC = 9.2 μL L −1 ). Hot water showed a complete inhibition of conidial germination in vitro after 10, 2 and 1 min of exposure at 40, 45 and 50 °C, respectively, and a complete inhibition of mycelial growth after 20 min of exposure at 75 °C. Among the volatile compounds tested, only 25 μL L −1 of carvacrol slightly reduced fungal infection on artificially infected apples (11.4% efficacy). Hot water treatment at 45 °C for 10 min showed high efficacy in the control of lenticel rot on apples. Reduction of infection was 80% in artificially inoculated fruit (cv Golden Delicious) and 90% in naturally infected fruit (cv Pink Lady) after 90 and 135 d of storage, respectively.

Cultivar ‘Femminello comune’ lemons of a yellow-green colour were stored at 0, 2, 5, 8, 10 or 12°C for 30, 60 or 90 days in 1987. Membranosis, a chilling injury of the carpellary membranes, had the highest incidence at 5°C. At the other temperatures tested, the disorder was lower at 0 and 2°C than at 8, 10 and 12°C. However, after storage at 0 or 2°C, the fruits developed rind pitting (another chilling injury). Temperature had a strong effect on ethanol concentrations in juice; by far the highest concentration was reached at 5°C. In 1989, fruits were exposed to 40% CO 2 for 3, 6 or 9 days and then stored at 0 or 12°C. Membranosis was considerably reduced by CO 2 with increasing effect from 3 to 6 or more days. CO 2 treatments also reduced rind pitting. The ethanol content of the juice was increased by CO 2 for 3 days or longer.

d s e, a s ed i tion o tch. ally w as a rgic ury d rev c F seudoaneurysm of the thoracic aorta results fr transmural disruption of the aortic wall, with eak contained by surrounding structures. Previous c iac surgery is the most frequent cause. Mechanis nclude infection, poor anastomotic technique, and rinsic aortic disease. A 52-year-old man underwent elective replacement o ysfunctional aortic bioprosthesis implanted 7 years bef or bicuspid aortic valve regurgitation. At re-do, the asce ng aorta, deemed not significantly dilated (42 mm O) ith preserved mechanical properties, was not replac he patient was readmitted 10 days after discharge w hest pain. A contrast-enhanced computed tomograph hest scan revealed a huge pseudoaneurysm of the asce ng aorta (10.6 9.5 11.9 cm; Fig 1A and 1B, asterisk) fed hrough a leak in the anterior aortic wall ( Fig 1A; sagittal lane, arrow) and closely related to the sternum ( Fig 1B; xial plane). Emergency extracorporeal circulation was established emoro-femoral cannulation and the sternum was ntered under moderate hypothermia (24°C). Using dir ntegrade brain perfusion, the pseudoaneurysm was e ered and its neck was identified at the previous aortot uture line. The friable ascending aorta and proximal ao rch were replaced with a 26 Vascutek prosthesis (Vasc erumo, Renfrewshire, Scotland). An aortic specim howed cystic medial changes of the elastic fibers ( Fig 2; ematoxylin and eosin, 10) with necrotic changes an ranulocytic infiltrate ( Fig 2; inset, arrow, 20). The culture ere negative. Patient recovery was uneventful. Fig 1.

A case of intraaortic balloon pump catheter migration after an ascending aortic insertion, occurring 16 h postoperatively in a 48 year old man after myocardial revascularization, is presented. The prevention and management of this rare but serious complication of intraaortic balloon pumping is reviewed.

Aortic valve replacement with the pulmonary autograft (ie, the Ross operation) is generally associated with satisfactory early and late results. Complications, however, can occur, including the tendency of the pulmonary autograft root to dilate with time. Whereas neoaortic root dilatation might be observed in as many as one third of patients late after the Ross operation, uncertainty still exists as to the rate of progression toward true aneurysmal disease (aortic diameter 5 cm). Furthermore, the actual risk of complications, such as neoaortic rupture or dissection, is also unknown. The yet undefined natural history of root dilatation after the Ross operation, the often satisfactory competence of the pulmonary autograft valve, the scarcity of valid therapeutic alternatives (particularly in the infant and child), and the complexity–risk of reintervention have thus far delayed standardization of therapeutic indications. In particular, timing and technique of reoperation on the aneurysmal neoaortic root are still controversial. Here we present a case of potentially lethal evolution of progressive pulmonary autograft dilatation (ie, neoaortic root dissection) successfully treated with valve-sparing root replacement. The implications in terms of natural history and indications for reintervention are discussed.

The residues on potatoes of the sprout inhibitors propham (IPC) and chloropropham (CIPC) applied as a powder or by aerosol were studied. Sprout inhibitor residues were determined after 15 and 30 days of storage in peeled and unpeeled potatoes. In the powder treatment containing IPC plus CIPC, only residues of IPC were found. In the aerosol treatment containing only CIPC, both CIPC and IPC were determined. Peeling potatoes resulted in large decreases in sprout inhibitor levels in the aerosol treatment. Both aerosol and powder applied CIPC and IPC prevented sprouting for more than 3 months.

Fungal endocarditis becomes complicated by peripheral arterial embolization of the lower limbs in 33%-75% of cases. Although the prognosis of patients with fungal endocarditis has improved somewhat over recent years, it remains poor, especially when the disease is associated with peripheral arterial embolization. We report herein our experience of treating a patient in whom occlusion of the right common iliac artery developed secondary to endocarditis caused by Candida parapsilosis, and review the literature on this subject.

Background . This study seeks to define the long-term results after Biocor PSB stentless aortic valve replacement (AVR) in elderly patients, including the effects of No-React treatment. Methods . We reviewed the outcomes of 106 consecutive patients, aged 70 ± 6 years, having Biocor PSB (93 standard, 13 No-React) AVR between October 1992 and October 1996. Results . There were three early deaths (3%) and 15 late deaths (15%), during a mean follow-up of 5.8 ± 1.6 years. At 8 years, survival was 82% ± 4% and freedom from cardiac death was 94% ± 3%. Freedom from valve failure was 92% ± 4% at 8 years (No-React: 92% ± 8% at 4 years). Replacement of the xenograft was required in 5 patients. Freedom from reoperation was 91% ± 4% at 8 years (No-React: 92% ± 8% at 4 years). Four bleeding and two embolic events were recorded: overall valve-related event-free survival was 81% ± 7% at 8 years (No-React: 76% ± 12% at 4 years). Age of long-term survivors averaged 77 ± 5 years and their New York Heart Association status was 1.3 ± 0.6 (versus 2.9 ± 0.6 preoperatively, p = 0.01). Conclusions . Satisfactory freedom from cardiac events and from valve deterioration added to uniform improvement in functional status despite advanced age and high prevalence of comorbid conditions make AVR with the Biocor PSB xenograft a valid long-term therapy for the elderly. No-React treatment does not influence xenograft durability.

Background . Stented aortic bioprostheses are routinely used in elderly patients. The stent, however, is obstructive and implies several hazards. Stentless aortic valves appear to be hemodynamically advantageous. However, their implantation is longer and technically more demanding, and durability is still under investigation. Methods . Between January 1993 and December 1996, 77 patients (28 men) were prospectively randomized to undergo aortic valve replacement using the Hancock valves (group A: 40 patients, 16 men; age, 77 ± 3 years; body surface area, 1.7 ± 0.17 m 2 ) or a stentless bioprostheses (group B: 37 patients, 12 men; age, 76 ± 2 years; body surface area, 1.7 ± 0.15 m 2 ; Biocor, 17; Toronto SPV, 20). Preoperative variables were not significantly different between the two groups. Bypass time was 123 ± 46 versus 133 ± 51 minutes, and aortic cross-clamp time was 83 ± 26 versus 95 ± 24 minutes for group A and group B, respectively (not significant). Seven patients in group A (17.5%) and 5 in group B (13.5%) had enlargement of the aortic annulus. Valve size normalized to body surface area was 13.7 ± 1.5 versus 14.1 ± 1.6 mm/m 2 for group A and group B, respectively (not significant). Eleven patients in group A (27.5%) and 5 in group B (13.5%) had concomitant myocardial revascularization. Results . Overall perioperative mortality was 5% in group A (low cardiac output in 2 patients), and 8% in group B (low cardiac output in 1; major neurologic event in 2). Follow-up is 97% complete (group A, 14.5 ± 10 months; group B, 18.5 ± 12 months). One patient in group B died at 28 months of myocardial infarction. Actuarial survival at 12 and 24 months is 92% versus 91% and 92% versus 81% for group A and group B, respectively. At 6 months, patients in group A showed a peak transaortic gradient of 25 ± 7 versus 20 ± 9 mm Hg in group B. Progressive regression of left ventricular mass expressed as a percentage of preoperative value was 10.5% and 19% for group A and group B at 1 year postoperatively (not significant). Conclusions . Stentless valves represent a valuable alternative to conventional prostheses in patients older than 75 years, although no great advantages with their use emerge from this study. Continued evaluation particularly with regard to evidence of left ventricular remodeling and valve degeneration in the long term is warranted. aortic valve, elderly, xenograft, stented bioprostheses

Background . The aim of the present study was to verify the efficacy of preserving the aortic valve in patients with acute type A aortic dissection complicated by significant aortic regurgitation. Methods . From January 1979 to December 1996, 178 patients (125 males; mean age 57 ± 9 years) underwent emergency surgery for acute type A aortic dissection, with an overall operative mortality rate of 21%. Based on a retrospective analysis of the preoperative angio- or echocardiographic findings, the 141 survivors were divided into 2 groups: Group 1 (G1) included 80 patients (57%) with no or mild aortic regurgitation, and Group 2 (G2) the remaining 61 patients with moderate-to-severe aortic regurgitation. The native aortic valve was preserved by means of a uniform technique consisting of reconstruction of the aortic root and sinotubular junction in 99 patients (70%) [68 in G1 (85%) and 31 in G2 (51%)]. Forty-two patients required aortic valve (8 patients; 6%) or total root replacement (34 patients; 24%). Results . At a mean follow-up of 4 ± 3.6 years (range, 6 months to 19 years), 19 of the 99 patients with a preserved aortic valve developed moderate-to-severe aortic insufficiency [19%; 7/68 in G1 (10%) and 12/31 in G2 (39%)]. Multivariate analysis revealed that moderate-to-severe preoperative aortic valve insufficiency was a significant risk factor for development of postoperative aortic valve regurgitation ( p = 0.008). Reoperation was necessary in 7 G1 patients (10%) and in 8 G2 patients (26%), with an actuarial freedom from reoperation at 5 and 10 years of 93% ± 7% and 80% ± 9% in G1 patients, and 81% ± 8% and 40% ± 15% in G2 patients ( p = 0.045). Conclusions . Preservation of the aortic valve and aortic root is recommended in patients with acute type A aortic dissection and absent or mild aortic insufficiency. Patients presenting with moderate-to-severe aortic regurgitation and treated conservatively present an increased risk of recurrent valvular insufficiency.

The mid-term results in a selected group of 9 patients with native aortic valve endocarditis managed by aortic valve replacement (with or without complex annular reconstruction) using a totally biological stentless valve are outlined. At a mean follow-up of 48 months, there are currently 7 survivors (2 late noncardiac deaths) with 100% freedom from reoperation, valve-related complication, and endocarditis.

Objective: The ideal substitute for the diseased aortic valve is yet to be found. For the assessment and comparison of the midterm results after aortic valve replacement with three different types of freehand stentless xenografts, all patients who underwent the operation between October 1992 and April 1997 were reviewed. Methods: Of 231 patients undergoing aortic valve replacement, 106 patients (group 1) were given the Biocor PSB (Biocor Industria e Pesquisa Ltda, Belo Horizonte, MG, Brazil); 76 patients (group 2) were given the Toronto SPV (St. Jude Medical, Inc., St. Paul, Minn.), and 49 patients (group 3) were given the O'Brien-Angell valve (Bravo Cardiovascular model 300, Cryolife, Inc., Marietta, Ga.). The first two xenografts require inflow and outflow suturelines; the third xenograft needs a single-sutureline implantation. Mean age (70 ± 6 years; 70 ± 7 years; 72 ± 9 years; p = 0.6), prevalence of male sex (56 patients, 53%; 37 patients, 49%; 22 patients, 45%; p = 0.7), of aortic stenosis (72 patients, 68%; 54 patients, 71%; 37 patients, 73%; p = 0.6), and need for associated procedures (51 patients, 48%; 30 patients, 40%; 21 patients, 43%; p = 0.1) were comparable among groups. Mean aortic crossclamp time was shorter in group 3 (96 ± 24 minutes; 100 ± 23 minutes; 88 ± 25 minutes; p = 0.01). Results: Early deaths were 3 of 106 (3%) in group 1, 2 of 76 (3%) in group 2, and 2 of 49 (4%) in group 3. Follow-up of survivors ranged from 1 to 54 months (mean 32 ± 13 months). Survival at 4 years was 90% ± 3% in group 1, 95% ± 3% in group 2, 85% ± 8% in group 3 ( p = 0.3). At 4 years, freedom from valve-related events was 95% ± 6%, 100%, 70% ± 8% ( p = 0.004), while freedom from valve deterioration was 99% ± 1%, 100%, 73% ± 8% ( p = 0.001), in group 1, 2, and 3, respectively ( p = 0.001). At follow-up, reintervention on the xenograft was necessary in one patient (endocarditis) in group 1, none in group 2, and six in group 3 (technical cause, group 3; valve tear, group 2; pannus, group 1). Regression analysis showed O'Brien-Angell type of xenograft to be predictive of valve-related events ( p = 0.02), valve deterioration ( p = 0.001), and reoperation ( p = 0.001) during follow-up. Conclusions: Midterm survival after stentless aortic valve replacement is good with all three xenografts. Freedom from valve-related events, valve deterioration, and reoperation are excellent with the Biocor PSB or the Toronto SPV stentless valves but less satisfactory with the O'Brien-Angell valve. (J Thorac Cardiovasc Surg 1998;115:1287-97)

Background . The midterm clinical results after aortic valve replacement with the Biocor PSB stentless xenograft on all patients operated between October 1992 and October 1996 were reviewed. Methods . One hundred six patients, aged 70 ± 6 years, had aortic valve replacement for aortic stenosis (67%), regurgitation (11%), or both (22%). Associated procedures were done in 49 patients (46%), including coronary artery bypass in 30 patients, mitral valve repair/replacement in 16, and ascending aorta replacement in 5 patients. Aortic cross-clamp and cardiopulmonary bypass times were 96 ± 24 and 129 ± 31 minutes, respectively. Results . There were 3 (3%) early deaths due to low output (2 patients) and cerebrovascular accident (1 patient). Follow-up of survivors ranged from 6 to 66 months (mean, 39 ± 14 months). Survival was 94% ± 2% and 90% ± 3% at 1 and 5 years. There were 5 late deaths due to cardiac cause (2), cancer (2), and pulmonary embolism (1 patient). No patient had structural valve deterioration, whereas 100% and 95% ± 3% were free from valve-related events at 1 and 5 years. There were two reoperations due to narrowing of the left coronary ostium and endocarditis, with an actuarial freedom from reoperation of 99% ± 1% and 98 ± 1% at 1 and 5 years, respectively. Functional results demonstrated a mean peak transprosthetic gradient of 16 ± 12 mm Hg, with only 1 patient (1%) with a 55 mm Hg gradient. No cases of valve regurgitation greater than mild were recorded at follow-up. Assessment of New York Heart Association functional class demonstrated a significant improvement (2.9 ± 0.6 versus 1.4 ± 0.7; p = 0.01). All patients were free from anticoagulation. Conclusions . Aortic valve replacement using the Biocor PSB stentless xenograft offers excellent midterm survival, negligible valve deterioration, and a very low rate of valve-related events, which are comparable to estimates reported with other models of stentless xenografts and currently available stented xenografts. Hemodynamic performance is favorable and quality of life satisfactory.

Spontaneous rupture of an aortic aneurysm into the pulmonary artery is unusual and is rarely reported in the literature. The case of a patient with a syphilitic aneurysm of the ascending aorta perforated into the pulmonary artery is presented. In an attempt to define the best surgical treatment for this complication the literature has been comprehensively reviewed.