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The resistance of immature grape berries to Botrytis cinerea Pers. ex Fr. results from a combination of factors, among which the accumulation of the stilbene phytoalexin t-resveratrol. Stilbene accumulation is thought to be induced by oligogalacturonides (OGs) which are released from the plant cell wall during tissue maceration catalysed by polygalacturonases (PGs) produced by necrotrophic fungal pathogens. Inhibitors of PG activity, the polygalacturonase- inhibiting proteins (PGIPs), have the capability to slow the hydrolytic activity of PGs and favour the accumulation of active OGs. In the present work we have observed that artificial inoculation of grape inflorescences and immature berries at bloom and post bloom, leads to severe infection of the rachis, while lesions on young berries did not result in the development of the disease, but in the development of necrotic spots and rings. PG was detectable in berry tissues, but its secretion was significantly lower than in infected leaves. Tissues of immature berries reacted to B. cinerea inoculation by a marked accumulation of t-resveratrol. PG produced during spore germination of B. cinerea elicited t-resveratrol accumulation. Apoplastic fluids (AFs) from immature berries and leaves were found to inhibit total PG activity produced by B. cinerea, indicating the involvement of a proteinaceous or non-proteinaceous PG inhibitor, or both, as intercellular defence mechanisms. Taken together, our results suggest that the inhibition of PG produced by B. cinerea mediated by a putative PG inhibitor during the early stages of infection of immature grape berries plays a central role in promoting accumulation of t-resveratrol and, consequently, the restriction of pathogen spread. [ABSTRACT FROM AUTHOR]

Variation of apoplastic pH by Fusarium culmorum and its influence on the production, activity and isoenzymes patterns of the pathogenesis-related (PR) proteins β1,3-glucanase, chitinase and peroxidase enzymes were detected in apoplastic fluids (AFs) from infected wheat seedlings. The time course in the 24–48 h interval post infection was characterized by an increase in activity and isoenzymatic differential induction of the selected PR proteins and by a concomitant rise of apoplastic pH. Chitinase attained maximum activity at pH 8·0 in the case of inoculated seedlings. Optimal β1,3-glucanase activity in the pH range 6·0–8·0, was observed at pH 7·0. Peroxidase was strongly affected by pH, with enzyme activity having a maximum rate at pH 6·0 and thereafter rapidly declining at higher pH. Maximum peroxidase activity paralleled the appearance of the complete isoenzymatic pattern. In order to investigate the biological role of PR proteins in AFs, the in vitro antifungal activity was evaluated. In the interval 0–6 h, pH of macroconidia suspensions rose up to 7·2. AFs revealed inhibitory activity against germinating macroconidia of F. culmorum by decreasing the germination efficiency of macroconidia apical compartments, while this effect was compensated by an increased germination capacity of middle compartments. Present results suggest that during infection of wheat seedlings by F. culmorum the pH modulation favours host colonization by enhancing the activity of pectin lyase, and simultaneously inhibits the capacity of the host to oppose the pathogen by interfering with peroxidases which represent an important component of the defence arsenal. [ABSTRACT FROM AUTHOR]

The effect on ambient pH of Fusarium culmorum during its growth on mineral medium and in apoplastic fluids from infected wheat seedlings, and the effect on the production and activity of the enzymes pectin lyase (PNL) and polygalacturonase (PG), were investigated. Fungal development on a weakly buffered mineral medium in the pH range 5·0–8·0, with pectin as the sole carbon source, led to pronounced alkalinization, reaching values above 8·0. The increase in ambient pH was accompanied by enhancement of total PNL activity. Pectin lyase secretion was detected at pH 5·0 as a single isoenzyme. An additional isoenzyme was apparent during the increase in medium pH. Polygalacturonase was detected as a single isoenzyme only during early growth on medium buffered at pH 5·0. At this stage, the initial medium pH of 5·0, corresponding to the optimum pH for PG activity, appeared to be the most suitable for the activation of early production of this enzyme. During growth in acidified yeast extract medium the fungus secreted ammonia and increased medium pH. Similarly, in apoplastic fluids from inoculated seedlings the concomitant ammonia accumulation and rise in pH were recorded. This trend was accompanied by an increase in PNL, which could therefore function at close to its optimal pH. The results suggest that during infection of wheat seedlings by F. culmorum, pH modulation can lead to PNL production and activity, thus promoting colonization of host tissue. [ABSTRACT FROM AUTHOR]

The plant signalling molecules methyl jasmonate (MeJA) and ethylene, alone and in combination, were tested by seed gaseous treatment for their ability to induce resistance in melon seedlings against gummy stem blight, white mould disease and fusarium wilt caused by the soil-borne fungal pathogens,Didymella bryoniae,Sclerotinia sclerotiorumandFusarium oxysporumf. sp.melonis, respectively. MeJA and ethylene treatments significantly enhanced the resistance level against the tested fungi, whereas when applied simultaneously their protective effect was less pronounced. Treatments with MeJA and ethylene were also tested in terms of biochemical responses by the measurement of variations of chitinase and peroxidase activities. MeJA treatment increased exochitinase activity in melon seedlings, whereas ethylene induced both exochitinase and peroxidase activities. Conversely, when combined, MeJA and ethylene consistently enhanced the activity of both exo- and endochitinase as well as peroxidase activity. The augmented level of chitinase and peroxidase activity was accompanied by the differential induction of an acidic chitinase isoenzyme and of both basic and acidic peroxidase isoenzymes. Results indicate that some inducible defences and associated resistance are independently enhanced in melon seedlings by the action of MeJA or ethylene, suggesting the coexistence of different resistance mechanisms. [ABSTRACT FROM AUTHOR]

Greenhouse and field evaluations of onion for resistance to Fusarium basal rot caused by Fusarium oxysporum f.sp. cepae were conducted on cultivars ‘Akgün 12’ and ‘Rossa Savonese’ previously described as resistant at the seedling stage. In the greenhouse experiments inoculations were carried out on seeds or soil; in the field experiments evaluation was performed on onion sets from plants grown in naturally infested soils. Akgün 12 and to a lesser extent Rossa Savonese were resistant to the disease at the bulb stage in all experiments. Results were also consistent with those obtained from a previous screening at the seedling stage. Onion sets were also extracted and fractionated by thin layer chromatography to determine their content of antifungal compounds. Extracts were characterized by the expression of distinct antifungal components, which may be involved in resistance to the pathogen. [ABSTRACT FROM AUTHOR]

The plant resistance activator acibenzolar- S-methyl (BTH), the signalling molecules salicylic acid (SA) and methyl jasmonate (MeJA) were tested by seed treatment for their ability to protect melon seedlings from gummy stem blight and white mould disease caused by the soil-borne fungal pathogens Didymella bryoniae and Sclerotinia sclerotiorum, respectively. Didymella bryoniae infection on melon seedlings was completely suppressed by MeJA treatment. Necrotic lesions akin hypersensitive response occurred on all inoculated seedlings and prevented pathogen diffusion into healthy tissues. Didymella bryoniae infection was restricted following BTH seed treatment as well, although the percentage of necrotic lesions in comparison with the water soaked lesions was significantly lower than that from MeJA-induced seedlings. BTH protected melon seedlings against S. sclerotiorum by the occurrence of a high percentage of necrotic lesions. A lower level of resistance was also achieved by MeJA seed treatment. The augmented level of resistance of tissues from BTH and MeJA-treated seeds was associated with rapid increases in the activity of the pathogenesis-related proteins chitinase and peroxidase. MeJA also determined a rapid and transient accumulation of lipoxygenase. Moreover, BTH and MeJA treatments determined the differential induction of particular de novo synthesized isoenzymes of these proteins. Results indicate that BTH and MeJA applied to melon seeds may activate on seedlings diverse metabolic pathways leading to the enhancement of resistance against distinct pathogens. [ABSTRACT FROM AUTHOR]

Objectives Fecal incontinence is a common, incapacitating and largely unrecognized medical problem and can be caused by various factors. Obstetric trauma is the most common cause of fecal incontinence secondary to trauma. We aimed to analyze the role of endoanal ultrasound in assessment of this type of fecal incontinence, and report the functional results of surgical treatment. Methods We reviewed the records of all 22 patients with fecal incontinence secondary to obstetric trauma who were evaluated by endoanal ultrasound and underwent surgical management in our department from April to 1997 to April 2002. Pre- and postoperative evaluation of the degree of incontinence was done using the incontinence score of Jorge and Wexner. Results The patients had a median age of 43 (range, 29–68) years. All had vaginal deliveries, five of which (22.7%) were instrumental. Most of the patients had total fecal incontinence (solids) with preoperative incontinence score values of 15–20 (median, 18). Endoanal ultrasound confirmed structural defects in the anterior external anal sphincter alone in 16 (72.7%) patients, and both anterior external and internal sphincter defects in six (27.3%) patients. A thinned perineal body was present in all patients. All patients received surgical treatment with overlapping sphincteroplasty and there was improvement of continence in 19 (86.4%) patients with postoperative incontinence score values between 4 and 0 (median, 2). Conclusions Endoanal sonography is an accurate method for assessing sphincter anatomy, delineating both internal and external anal sphincters. Surgical treatment of sphincter defects is associated with good outcome. [ABSTRACT FROM AUTHOR]

Analyzes the ability of two Fusarium oxysporum f. sp. cepae isolates, FOC6 and FOC8, to colonize onion seedlings, following seed inoculation of different cultivars, and the associated quantitative and qualitative polygalacturonase and pectin lyase production. Lower pectolytic enzyme production from FOC6 than that of the FOC8 isolate; Factors influencing disease severity during onion colonization by F. oxysporum f.sp. cepae.

We report our experience and results in the management of Fournier's gangrene. Fournier's gangrene is a synergistic infective necrotizing fasciitis, which involves perianal, perineal and genital regions, originated mostly from colorectal and genitourinary sources. Charts and records from 28 patients with Fournier's gangrene diagnosed between 1993 and 1997 were reviewed. The mean patients age was 57.8 years (range, 22–82 years); mean hospital stay was 19 days. Eighteen patients (64.3%) were diabetic. The most common source of gangrene was ischiorectal abscess in 22 patients (78.6%). Colostomy was performed on 14 patients (50%) and cystostomy on 7 patients (25%). Ten patients (35.7%) died because of sepsis. In conclusion, medical and surgical treatment should be aggressive. Colostomy should only be performed if sphincter complex is damaged. Multidisciplinary management is mandatory, because of high morbidity and mortality. [ABSTRACT FROM AUTHOR]

Evaluates the resistance of melon rootstocks to the fungal pathogen Didymella bryoniae in glasshouse conditions. Leaf and stem disease indices; Occurrence of limited symptoms; Cultivation of susceptible melon cultivars grafted on resistant rootstocks.

Glyceollin I was fungistatic rather than fungicidal toward Sclerotinia sclerotiorum. Within the mycelial mat apical cells were more vulnerable than mature cells. S. sclerotiorum removed large amounts of glyceollin from solution by a non-energy-requiring process. [ABSTRACT FROM AUTHOR]

Polygalacturonase, Xylanase and Cellulase in Seiridium cardinale grown on cypress cell walls and on infected cypress shoots were detected. Isoenzymes were resolved by isoelectric focusing and differences were found between "in vivo" and "in vitro". [ABSTRACT FROM AUTHOR]

Copyright of European Journal of Forest Pathology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since cryptorchidism can cause infertility and early orchiopexy can improve fertility, we tried to determine whether medical and surgical treatment in the 1st year of life can improve testicular fertility. We concluded that this is the best time to treat cryptorchid tests. [ABSTRACT FROM AUTHOR]

Pectolytic enzymes produced by Didymella bryoniae in a liquid medium containing pectin as sole carbon source and in inoculated etiolated hypocotyls of 10 melon cultivars, as well as those constitutively expressed in spores, were studied by isoelectric focusing, quantitatively and qualitatively. Five constitutive pectin lyase (PNL) isoenzymes differing in isoelectric joint (pI), one acidic (pI 3.9) and four basic (pI 8.4, 8.9, 9.3, 9.9) were expressed in extracts from spores. The same PNL isoenzyme pattern was detected in culture filtrates and in infected tissues of all the melon cultivars tested. Polygalacturonase (PG) activity, represented by a single inducible acidic band (pI 4.6) was detected only in culture filtrates. A single constitutive basic pectin methylesterase (PME) isoenzyme (pI > 10.0) was also found in spores, culture filtrates and inoculated melon tissues. All cultivars were susceptible at the seedling growth stage, but with differences in disease severity; cultivars Amarillo Oro and Juane Canari were, respectively, the least and most susceptible. Pectin lyase activity was highly correlated with disease severity. In rotted tissues and culture filtrates, an increase in pH to values over 7.0 was recorded, values optimal for PNL activity. In this plant–pathogen interaction, PNL activity represents the principal pectolytic component and these isoenzymes were associated with the onset of disease, disease severity and an increase in pH of infected tissue. [ABSTRACT FROM AUTHOR]

Late perforation after ventriculoperitoneal (VP) shunting is extremely rare. Colonic perforation is uncommon and represents 0.1%–0.7% of abdominal complications. Colonic perforation can challenge diagnostic and therapeutic decisions, and there are no clear guidelines on the management of this problem. We present a 34-year-old woman who was admitted for a 1-week history of sensation of a foreign body through the anus at the time of bowel movements. She had previously undergone a VP derivation for hydrocephalus secondary to neurocysticercosis. Plain abdominal radiographs demonstrated the shunt within the colonic lumen and through the descendening and sigmoid colon. The shunt was exteriorized in the cervical area and a laparotomy was performed with a primary two-layer colonic close. The patient received antibiotic therapy for 2 weeks with good outcome. Percutaneous and endoscopic approaches have been reported in patients with no abdominal signs. Prompt recognition of this complication is critical to avoid high mortality rates. [ABSTRACT FROM AUTHOR]

An obituary for Paolo Alghisi, a former physiological plant pathology professor at the University of Padua in Italy, is presented.

The article presents a case report of leukaemia in which its first clinical manifestation was lower gastrointestinal bleeding secondary to colonic leukaemic infiltration in a 70-year-old male patient. The patient presented with massive, spontaneous lower gastrointestinal bleeding. He was haemodynamically unstable but the abdomen was soft and non-tender, with no palpable organs or masses. The patient underwent a right hemicolectomy with terminal ileostomy after finding ulcer in the caecum.

An abstract of the article "Gnomoniopsis associated with necrosis of leaves and chestnut galls induced by Dryocosmus kuriphilus," by P. Magro and colleagues is presented.

Copyright of Journal of Phytopathology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)