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1.
Plant Dis ; 97(5): 688, 2013 May.
Article in English | MEDLINE | ID: mdl-30722220

ABSTRACT

Mimosa [Acacia dealbata Link, syn. Acacia decurrens (Wendl. F.) Wild. var. dealbata (Link) F. Muell., Fabaceae] is an evergreen shrub native to southeastern Australia that is cultivated as an ornamental plant in warm temperate regions of the world. In spring 2010, in a commercial nursery in Liguria (northern Italy), 6- to 10-month-old potted plants of A. dealbata showed symptoms of sudden collapse, defoliation, and wilt associated with root and basal stem rot. An abundant gum exudate oozed from the basal stem. A Phytophthora species was consistently isolated from roots and stem on BNPRAH selective medium (4). On V8 agar (V8A), axenic cultures obtained by single hyphal transfers formed stellate to radiate colonies with aerial mycelium whereas on potato dextrose agar (PDA) the colonies grew more slowly than on V8A and showed stoloniform mycelium and irregular margins. Minimum and maximum growth temperatures on PDA were 10 and 35°C, with the optimum at 30°C. In water, all isolates produced catenulate or single fusiform hyphal swellings and ellipsoid, nonpapillate, persistent sporangia. Dimensions of sporangia were 46.1 to 65.4 × 23.1 to 30.8 µm (mean l/b ratio 2.1). All isolates were A1 mating type and produced spherical oogonia with amphyginous antheridia when paired with A2 mating type of P. drechsleri Tucker on V8A plus ß-sytosterol (4). Internal transcribed spacer (ITS) regions of rDNA of the representative Phytophthora isolate IMI 500394 from A. dealbata were amplified and sequenced in both directions with primers ITS6/ITS4. The consensus sequence (GenBank Accession No. JF900371) was 99% similar to sequences of several isolates identified as Phytophthora taxon niederhauserii Z.G. Abad and J.A. Abad (e.g., GQ848201 and EU244850). Pathogenicity tests were performed on 1-year-old potted plants of A. dealbata with isolate IMI 500394. Twenty plants were transplanted into pots (12-cm-diameter) filled with soil infested (4% v/v) with the inoculum of IMI500394 produced on kernel seeds. Plants were kept in a greenhouse with natural light at 25 ± 2°C and watered to field capacity weekly. All inoculated plants showed symptoms of wilt, leaf chlorosis, and basal stem rot within 3 to 4 weeks. Twenty control plants transplanted in autoclaved soil mix remained healthy. P. taxon niederhauserii was reisolated solely from inoculated plants, thus fulfilling Koch's postulates. Since 2003, this pathogen has been found on bottlebrush and rock rose grown in a nursery in Sicily (southern Italy), as well as on Banksia in a nursery in Liguria (2,3). To our knowledge, this is the first report of P. taxon niederhauserii on A. dealbata. P. taxon niederhauserii, recently described as P. niederhauserii sp. nov. (1), is a polyphagous pathogen that was originally reported on arborvitae and ivy in North Carolina in 2001. References: (1) Z. G. Abad et al. Mycologia (in press), 2013. (2) S. O. Cacciola et al. Plant Dis. 93:1075, 2009. (3) S. O. Cacciola et al. Plant Dis. 93:1216, 2009. (4) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996.

2.
Plant Dis ; 97(1): 152, 2013 Jan.
Article in English | MEDLINE | ID: mdl-30722264

ABSTRACT

In 2008 and 2009, necrotic bark lesions at the root collar and lower stem associated with root rot, reduced growth, and wilting were observed on container-grown common box (Buxus sempervirens L.), lavender (Lavandula angustifolia Mill. 'Hidcote'), and Port-Orford-cedar (Chamaecyparis lawsoniana (A. Murray) Parl. 'Columnaris') in three ornamental nurseries in western Hungary. Number of affected plants ranged from approximately 100 (Port-Orford-cedar) to 250 (lavender). Isolations from necrotic root collars of each host plant species yielded four Phytophthora isolates developing uniform colonies on carrot agar with a maximum growth temperature of 35 to 36°C. The isolates were homothallic with smooth-walled oogonia (32.2 ± 2.3 to 35.9 ± 3.5 µm), aplerotic oospores (27.5 ± 1.8 to 32.1 ± 3.1 µm) and both amphigynous and paragynous antheridia, and produced chlamydospores (25.8 ± 3.9 to 29.1 ± 5.2 µm) and papillate sporangia (35.2 ± 2.5 to 43.5 ± 5.6 µm long and 27.6 ± 2.2 to 32.0 ± 3.8 µm wide), mostly obpyriform to nearly spherical or rarely distorted with two or three apices. In spring water, sporangia were both caducous with short pedicel and non-caducous. Multiplex ITS-PCR assay of DNA from all isolates, using primers specific for P. nicotianae (NICF1 and NICR2.1) and P. cactorum (CACTF1 and CACTR1) (1), amplified DNA fragments of the expected size for each Phytophthora species. In addition, isoenzyme analysis revealed a characteristic banding pattern of one heterodimer and two homodimer bands at both loci of the dimeric enzyme malate dehydrogenase. These bands comigrated with those of P. × pelgrandis (Gerlach et al.) (CBS 123385) and isolate PD 93/1339 (courtesy of W. A. Man in 't Veld), two natural hybrid strains of P. nicotianae and P. cactorum (2,3), proving that our four isolates can be referred to as this interspecific hybrid. Pathogenicity was tested on 1- or 3-year-old plants of the original host species and cultivars (for common box, cv. Faulkner was used). Cultures were grown for 4 to 6 weeks at 20°C on autoclaved millet grains moistened with V8 broth. Infested and uninfested grains were mixed with autoclaved soil in a ratio of 6% (w/v), and the mixes were used as potting media for transplanting five treated and five control plants per isolate, respectively. Plants were kept in a growth chamber (20°C, 70% RH, 12-h photoperiod). Pots were flooded for 24 h on the 1st and 21st day after transplanting. All plants in infested potting mix showed symptoms of wilt associated with basal stem and root necrosis, similar to those observed on the plants from the field, within 2 and 3 months on lavender and both common box or Port-Orford-cedar, respectively. Additionally, a reduction of root weight ranging from 35 to 68% compared to the control was recorded. Growth reduction was significant at P ≤ 0.019 according to Mann Whitney test. Control plants remained healthy. The same Phytophthora hybrid was reisolated solely from inoculated plants. In Europe, hybrid isolates of P. nicotianae × P. cactorum have been reported on several ornamental plants, including lavender, in the Netherlands and Germany (2,3). However, to our knowledge, this is the first report of this hybrid in Hungary and as a pathogen of common box and Port-Orford-cedar in the world. References: (1) P. J. M. Bonants et al. Phytopathology 90:867, 2000. (2) W. A. Man in 't Veld et al. Phytopathology 88:922, 1998. (3) H. I. Nirenberg et al. Mycologia 101:220, 2009.

3.
Plant Dis ; 95(6): 776, 2011 Jun.
Article in English | MEDLINE | ID: mdl-30731894

ABSTRACT

The evergreen carob tree (Ceratonia siliqua L., Fabaceae), also called locust, is widespread in the Mediterranean Region. Carob pods have been traditionally consumed as animal and human food and seeds are mainly used in the pharmaceutical and cosmetic industries. In July 2009, symptoms of canker, branch dieback, and foliage reddening were observed on carob trees in several natural areas in the province of Ragusa, Italy. Disease incidence ranged from 5 to 80% across different sites and for most areas it was nearly 15%. All affected trees showed dark necrotic tissue in the bark, cambium, and sapwood of the trunk and branches. Cankers often girdled the stem or branch, causing wilting and death of the portions beyond the canker. Black, subepidermal pycnidia developed in and erupted through the dead bark. Fragments of discolored wood were collected from 36 symptomatic carob trees (12 trees for each area), transferred onto potato dextrose agar (PDA), and incubated for 5 days at 21°C in the dark. Fungal colonies were consistently obtained from these diseased tissues. They initially were pale, becoming gray-green and finally black. After 30 days of incubation at room temperature in the natural light, colonies produced pycnidia identical to those observed in nature. A total of 500 conidia on 10 isolates were examined with a compound microscope. Conidia were initially hyaline, smooth, oblong to ovoid, both ends rounded, and aseptate; at maturity they were pale brown, one-septate, and measured 24 to 28 × 10 to 13.5 µm (means ± S.D. = 24.3 ± 1.4 × 12.1 ± 1 µm, L/W = 2.0 ± 0.18). The nucleotide sequences of the ß-tubulin (GenBank Accession No. HQ660080) and TE-1α (No. HQ660078) genes and ITS-rDNA region (No. HM028640) for a representative isolate (IMI 390972) from carob showed 100, 100, and 98% similarity, respectively, when compared with the sequences HQ660079, EU392279, and EU392302, respectively, of the ex-type isolate of Diplodia olivarum (strain CBS 121887). On the basis of morphological and molecular characters, the fungus was identified as D. olivarum A.J.L. Phillips, Frisullo & Lazzizera; teleomorph unknown (1). Two-year-old trees were wounded with a scalpel through the full thickness of the bark along 1-cm longitudinal direction and inoculated by applying a 5-mm-diameter plug of mycelial (isolate IMI 390972) on PDA to the wound site. Three control seedlings were similarly wounded and plugs of sterile PDA applied. Plugs were held in place by Parafilm. The inoculated seedlings were maintained at 20 to 22°C and a 12-h light/dark cycle. Sixty days after inoculation, all inoculated trees showed leaf chlorosis, sunken, necrotic bark at the inoculation sites and finally pycnidia of D. olivarum. All treated seedlings were killed within 6 months from the inoculation. No symptoms were observed in the control plants. The pathogen was consistently reisolated from all the inoculated trees, but not from the control plants. D. olivarum has been found on rotting olive drupes in Apulia (southern Italy) and was first described as a new species in 2008 (1). This fungal species could be phenotypically misidentified as the closely related species D. mutila, which differs by having larger mean dimensions of conidia. To our knowledge, this is the first report of D. olivarum inducing canker and dieback on carob tree. Reference: (1) C. Lazzizera et al. Fungal Divers. 31:63, 2008.

4.
Plant Dis ; 95(3): 362, 2011 Mar.
Article in English | MEDLINE | ID: mdl-30743524

ABSTRACT

The genus Aeonium, family Crassulaceae, comprises approximately 35 species that are native to northern Africa and the Canary Islands. Tree aeonium (Aeonium arboreum (L.) Webb & Berthel.) is a bushy, perennial succulent with rosettes of tender, waxy leaves at the apex of few-branched or occasionally single, naked stems. Mature rosettes bear yellowish inflorescences. Aeoniums are cultivated as ornamentals in gardens and containers. During the summer of 2009, in a garden in eastern Sicily (southern Italy), 3-year-old potted plants of tree aeonium showed stunting, shrivelling, and chlorosis of leaves and drop of external leaves associated with root and basal stem rot. Drops of an amber exudate oozed from the basal stem. Tissues of the basal stem were soft, but no external necrosis was visible. A species of Phytophthora was consistently isolated from symptomatic roots and basal stem tissues on a medium selective for Oomycetes (2). Axenic cultures were obtained by single-hypha transfers. The pathogen was identified by morphological criteria as Phytophthora nicotianae B. de Haan; it formed stoloniferous colonies on potato dextrose agar and grew between 8 and 38°C, with the optimum at 30°C. On V8 juice agar it produced spherical, intercalary chlamydospores (mean diameter of 26 µm) and persistent, mono- and bipapillate, spherical to ovoid, ellipsoid, obpyriform sporangia that measured 29 to 56 × 22 to 45 µm with a mean length/breadth ratio of 1.3:1. All isolates were A2 mating type and formed spherical oogonia (mean diameter 28 ± 2 µm) with smooth walls and amphigynous antheridia in dual cultures with a reference isolate of the A1 mating type of P. nicotianae. BLAST analysis of the internal transcribed spacer (ITS) region of rDNA of a representative isolate from aeonium (IMI 398812, GenBank Accession No. HQ433333) amplified by PCR using the ITS6/ITS4 universal primers (1), revealed 99% similarity with the sequences of a reference isolate of P. nicotianae available in GenBank (Accession No. EU331089.1). Pathogenicity of isolate IMI 398812 was demonstrated by transplanting cuttings of A. arboreum into pots filled with a mixture of steam-sterilized sandy loam soil and inoculum (4% vol/vol) produced by growing the isolate for 20 days on wheat kernels. Ten plants were transplanted into 3-liter pots (two plants per pot) while 10 plants, transplanted into pots filled with a mixture of steam-sterilized soil and noninoculated kernels, were used as controls. Plants were kept in a greenhouse at 25 to 28°C and watered daily to field capacity. Thirty to forty days after the transplanting into infested soil, cuttings developed the same symptoms observed on plants with natural infections. Control plants remained symptomless. P. nicotianae was reisolated from symptomatic plants, thereby completing Koch's postulates. To our knowledge, this is the first report of P. nicotianae on an Aeonium species worldwide. The economic relevance of this disease is minor because aeoniums are not cultivated on a large scale. Moreover, the disease may be easily prevented by avoiding excess irrigation water since aeoniums need a well-drained soil or potting mix and do not tolerate soil waterlogging. References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) H. Masago et al. Phytopathology 67:425, 1977.

5.
Plant Dis ; 95(6): 769, 2011 Jun.
Article in English | MEDLINE | ID: mdl-30731928

ABSTRACT

In June 2009 in a commercial nursery in eastern Sicily (Italy), 3-year-old potted windmill palms (Trachycarpus fortunei (Hooker) H. Wendl.) showed a decline in growth, wilt, droop, and basal rot of the youngest leaves. The rot progressed inward and killed the bud. Initially, older leaves remained green but eventually the entire plant collapsed. Root rot was consistently associated with aboveground symptoms. Two Phytophthora species were consistently isolated from the petiole base, heart, roots, and rhizosphere soil of symptomatic plants on a selective medium (2) and occasionally recovered from roots and rhizosphere soil of asymptomatic plants. Pure cultures were obtained by single-hypha transfers and the two species were identified on the basis of morphological and molecular characters as Phytophthora palmivora and P. nicotianae. Both species were recovered from all symptomatic plants. From multiple tissue samples per plant, we recovered either or both species. On potato dextrose agar (PDA), P. palmivora isolates grew between 10 and 35°C, with the optimum at 27°C. On V8 juice agar, they produced elliptical to ovoid, papillate, caducous sporangia (32 to 78 × 23 to 39 µm) with a mean length/breadth (l/b) ratio of 1.8:1 and a short pedicel (mean pedicel length = 5 µm). Isolates of P. nicotianae produced arachnoid colonies on PDA, grew at 37°C but did not grow at 40°C. Sporangia (29 to 55 × 23 to 45 µm) were spherical to ovoid (l/b ratio 1.3:1), papillate and often bipapillate, and noncaducous. Isolates of both species produced amphigynous antheridia and oogonia only when paired with reference isolates of P. nicotianae of the A2 mating type. The internal transcribed spacer (ITS) region of rDNA of two isolates of P. palmivora (IMI 398987 and IMI 398988) and an isolate of P. nicotianae (IMI 398989) from T. fortunei was amplified with primers ITS6/ITS4 and sequenced (1). Blast analysis of the sequences of isolates IMI 398987 and IMI 398988 (GenBank Accession Nos. HQ596556 and HQ596558) showed 99% homology with the sequence of two reference isolates of P. palmivora (GQ398157.1 and GU258862), while the sequence of isolate IMI 398989 (HQ596557) showed 99% homology with a reference isolate of P. nicotianae (EU331089.1). Pathogenicity of isolates IMI 398987 and IMI 398989 was proved by inoculating separately each isolate on 1-year-old potted plants of T. fortunei (10 plants per isolate). A zoospores suspension (2 × 104 zoospores/ml) was pipetted onto the petiole base of the three central leaves (200 µl per leaf) of each plant. Sterile water was used for control plants. All plants were incubated at 25 ± 2°C with 100% humidity for 48 h and then maintained in a greenhouse at 24 to 28°C. Within 3 weeks, all inoculated plants showed symptoms of bud rot. Control plants remained healthy. P. palmivora and P. nicotianae were reisolated only from inoculated plants. Bud rot of palms caused by P. palmivora was reported previously in Italy (3). However, to our knowledge, this is the first report of simultaneous infections of P. palmivora and P. nicotianae as causal agents of this disease. Outbreak of bud rot may have been favored by overhead sprinkler irrigation. The recovery of P. palmivora and P. nicotianae from rhizosphere soil and roots of asymptomatic plants suggests infested soil was the primary inoculum source. References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) H. Masago et al. Phytopathology 67:425, 1977. (3) A. Pane et al. Plant Dis. 91:1059, 2007.

6.
Plant Dis ; 94(11): 1374, 2010 Nov.
Article in English | MEDLINE | ID: mdl-30743638

ABSTRACT

Approximately 150,000 potted mandevillas (Apocynaceae) are produced each year in the Etna District of eastern Sicily. Since 2004, leaf chlorosis, wilt, and sudden collapse of the entire plant associated with root and basal stem rot of 6- to 12-month-old potted mandevillas, including Mandevilla × amabilis 'Alice du Pont', M. splendens, and M. sanderi 'Alba', 'My Fair Lady', and 'Scarlet Pimpernel', have been observed in six nurseries. Incidence of affected plants varied from 5 to 40%. Four Phytophthora species were consistently isolated from rotted roots and stems on a selective medium (2). Pure cultures of the first species produced colonies with a camellia pattern on potato dextrose agar and grew between 10 and 37°C with an optimum of 27°C. On V8 juice agar they produced ellipsoid to obpyriform (length/breadth [l/b] 1.45:1), nonpapillate sporangia with internal proliferation, coralloid, spherical hyphal swellings and both terminal and intercalary chlamydospores. In dual cultures with A1 and A2 isolates of P. nicotianae, all isolates produced oogonia with amphyginous antheridia only with A2 isolates. Isolates of the second species formed petaloid colonies, had an optimum growth temperature of 25°C, and produced mono- and bipapillate, ovoid to limoniform sporangia (l/b 1.40:1); they did not produce gametangia. Isolates of the third species formed colonies with a slight petaloid pattern and grew between 2 and 30°C with an optimum of 25°C. Sporangia were obpyriform (l/b 1.48:1), nonpapillate, and proliferous. All isolates were A2 mating type. The isolates of the fourth species formed arachnoid colonies, grew between 8 and 38°C with an optimum of 30°C, and produced mono- and bipapillate, ellipsoid, and obpyriform (l/b 1.3:1) sporangia and apical chlamydospores. All isolates were A2 mating type. DNA was extracted from mycelium and amplified by PCR using the ITS 4/ITS 6 primers (1). Blast search of the rDNA-ITS sequence of isolate IMI 397618 (GenBank Accession No. GQ388261) of the first species showed 100% identity with the ITS sequence of an isolate of P. cinnamomi var. parvispora (EU748548). The sequences (GQ463703 and GQ463704) of isolates IMI 397471 and IMI 397472 of the second species showed 99% similarity with the sequences of a P. citrophthora isolate (EU0000631). The sequence of isolate IMI 397473 (GQ463702) of the third species showed 99% similarity with the sequence of a P. cryptogea isolate (AY659443.1), while the sequence of isolate IMI 397474 (GU723474) of the fourth species showed 99% similarity with the sequence of a P. nicotianae isolate (EU331089). The pathogenicity of individual isolates IMI 397618, IMI 397471, IMI 397472, IMI 397473, and IMI 397474 was tested on 3-month-old potted plants (10 plants per isolate) of mandevilla 'Alice du Pont' by applying 10 ml of a suspension (2 × 104 zoospores/ml) to the root crown. Plants were maintained at 25°C and 95 to 100% relative humidity. All inoculated plants wilted after 4 weeks, while noninoculated control plants remained healthy. The four Phytophthora spp. were subsequently reisolated only from symptomatic plants. To our knowledge, this is the first report of P. cinnamomi var. parvispora in Italy and on mandevilla worldwide. In recent years, Phytophthora root and stem rot has become the most serious disease of potted mandevillas in Sicily. References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) H. Masago et al. Phytopathology 67:425, 1977.

7.
Plant Dis ; 94(11): 1372, 2010 Nov.
Article in English | MEDLINE | ID: mdl-30743653

ABSTRACT

In summer 2008, leaf chlorosis, defoliation, exceptional fruit set, twig dieback, and wilt were observed on 4-year-old olive (Olea europea L.) trees cv. Tonda Iblea in a drip-irrigated orchard in eastern Sicily. Rot of fine roots was associated with these symptoms and on ~15% of symptomatic trees rot extended to the crown and basal stem. Trees declined slowly or collapsed suddenly with withered leaves still attached. Incidence of affected trees was ~10%. A fungus identified as Verticillium dahliae Kleb. was isolated from the xylem of main roots and basal stem. An oomycete identified as Phytophthora palmivora (Butler) Butler was isolated from roots and basal trunk bark. Both pathogens were recovered from symptomatic trees with mean frequency of positive isolations per tree of 80 and 30% for V. dahliae and P. palmivora, respectively. To isolate V. dahliae, wood chips were surface disinfested in 0.5% NaOCl for 1 min and plated onto potato dextrose agar (PDA). The fungus was identified on the basis of microsclerotia, verticillate arrangement of phialides on conidiophores, and hyaline single-celled conidia. Ten monoconidial isolates were characterized by PCR using primer pairs INTND2f/INTND2r and DB19/espdef01 (3). Only 824-bp amplicons, diagnostic of the virulent, nondefoliating V. dahliae pathotype, were obtained. P. palmivora was isolated on selective medium (2) and pure cultures were obtained by single-hypha transfers. Colonies grew on PDA between 10 and 35°C (optimum at 27°C). Chlamydospores and elliptical to ovoid, papillate, caducous (mean pedicel length = 5 µm) sporangia (length/breadth ratio of 1.8) were produced on V8 juice agar. All isolates were paired with reference isolates of P. nicotianae and produced gametangia only with isolates of the A2 mating type. PCR amplicons of a representative isolate generated using primers ITS 6 and ITS 4 (1) were sequenced and found to be identical to those of a reference isolate of P. palmivora (GenBank No. AY208126). Pathogenicity of V. dahliae (IMI 397476) and P. palmivora (IMI 397475) was tested on 6-month-old rooted cuttings of olive cv. Tonda Iblea. Ten cuttings were transplanted into pots with steam-sterilized soil and inoculum of P. palmivora (4% vol/vol) produced on wheat kernels. Ten olive cuttings were inoculated with V. dahliae by injecting the stem with 150 µl of a conidial suspension (107 conidia ml-1) and 10 cuttings were stem inoculated with V. dahliae and transplanted into soil infested with P. palmivora. Controls were 10 noninoculated cuttings transplanted into steam-sterilized soil. Pots were kept in a greenhouse (25 ± 3°C) for 4 months. No aerial symptoms were observed on cuttings transplanted into soil infested with P. palmivora. However, root dry weight was reduced by 40% in comparison with the controls. Cuttings inoculated solely with V. dahliae had a 15% reduction in height compared with the controls but only four cuttings wilted. All cuttings inoculated with P. palmivora and V. dahliae wilted, indicating a synergism between the two pathogens. Controls remained healthy. Each pathogen was reisolated solely from inoculated cuttings and both pathogens were reisolated from cuttings with double inoculations. A similar syndrome 'seca' (drying) was reported in Spain (4). References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) H. Masago et al. Phytopathology 67:425, 1977. (3) J. Mercado-Blanco et al. Plant Dis. 87:1487, 2003. (4) M. E. Sánchez-Hernández et al. Eur. J. Plant Pathol. 104:34, 1998.

8.
Plant Dis ; 93(10): 1075, 2009 Oct.
Article in English | MEDLINE | ID: mdl-30754367

ABSTRACT

Bottlebrush (Callistemon citrinus (Curtis.) Skeels., Myrtaceae) and rock rose (Cistus salvifolius L., Cistaceae) are evergreen shrubs native to Australia and the Mediterranean Region, respectively. In the spring of 2003, approximately 2% of a nursery stock of 12-month-old potted plants of C. citrinus and 8% of a nursery stock of 12-month-old potted plants of Cistus salvifolius grown in the same nursery in Sicily, showed symptoms of leaf chlorosis, defoliation, and wilt associated with root and collar rot. A Phytophthora species was consistently isolated from roots and basal stems on BNPRAH selective medium (2). One isolate from rock rose (IMI 391708) and one from bottlebrush (IMI 391712) were characterized. On potato dextrose agar (PDA), the colonies showed stoloniform mycelium and irregular margins; on V8 juice agar (V8A), colonies were stellate to radiate. Minimum and maximum temperatures on PDA were 10 and 35°C, respectively, with the optimum at 30°C. Mean radial growth rate of isolates on this substrate was 9.9 and 11.3 mm/day, respectively. In saline solution (1), both isolates produced catenulate hyphal swellings and ellipsoid, nonpapillate, persistent sporangia with internal proliferations and dimensions of 52 to 70 × 30 to 42 µm and 51 to 85 × 39 to 45 µm. Mean l/b ratio of sporangia for both isolates was 1.8 ± 1. On V8A plus ß-sytosterol, both isolates produced amphyginous antheridia and spherical oogonia in dual cultures with an A2 tester of P. drechsleri Tucker. Conversely, they did not produce gametangia with an A1 tester of P. cryptogea Pethybr., indicating they were A1 mating type. The internal transcribed spacer (ITS)-rDNA sequences of rock rose and bottlebrush isolates showed 100% similarity with those of two reference isolates of P. taxon niederhauserii from GenBank (Accession Nos. FJ648808 and FJ648809). On the basis of the analysis of the DNA, the species isolated from bottlebrush and rock rose were identified as Phytophthora taxon niederhauserii. Pathogenicity tests were carried out on 6-month-old potted plants of C. salvifolius and C. citrinus (10 plants of each plant species for each isolate) transplanted into pots (12 cm in diameter) containing a mixture of 1:1 steam-sterilized, sandy loam soil (vol/vol) with 4% inoculum produced on autoclaved kernel seeds. Plants were maintained at 25 to 28°C and watered to soil saturation once a week. After 2 to 3 weeks, all inoculated plants developed symptoms identical to those observed on plants with natural infections. Ten control plants transplanted into pots containing noninfested soil remained healthy. P. taxon niederhauserii was reisolated solely from inoculated plants. To our knowledge, this is the first report of P. taxon niederhauserii on C. citrinus and C. salvifolius in Italy. This Phytophthora taxon has been reported recently on rock rose in Spain (3). References: (1) D. W. Chen and G. A. Zentmyer. Mycologia 62:397, 1970. (2) H. Masago et al. Phytopathology 67:425, 1977. (3) E. Moralejo et al. Plant Pathol. 58:100, 2009.

9.
Clin Exp Rheumatol ; 26(6): 1095-8, 2008.
Article in English | MEDLINE | ID: mdl-19210877

ABSTRACT

BACKGROUND: Oxidative stress has been considered a leading factor in the pathogenesis of systemic sclerosis (SSc). Consistently with this hypothesis the determination of urinary isoprostanes, a reliable method for evaluation of oxidative stress, has recently showed increased levels of isoprostanes in SSc patients. Data about the effect on oxidative stress of accepted therapies for SSc such as iloprost therapy are lacking. OBJECTIVE: The aim of this prospective study was to verify whether iloprost therapy in patients with SSc acutely reduces oxidative stress assessed by determination of 8-Iso PGF2alpha urinary levels. METHODS: urine samples were obtained before and after a five-day cycle of iloprost infusion and urinary 8-Iso PGF2alpha levels were determined using a commercially available enzyme immunoassay. RESULTS: Consistent with previous reports, we found an increased level of oxidative stress in SSc patients with respect to healthy controls. Basal urinary 8-iso PGF2alpha levels in SSc patients were significantly higher than those in healthy controls [2002(1122-3575) pg/mg creatinine vs. 334(225.7-441) pg/mg creatinine, p<0.001]. Moreover, as expected, urinary 8-iso PGF2alpha levels after iloprost therapy were significantly lower than basal levels [1277.5 pg/mg creatinine (742.7-2017.3) vs. 2002 pg/mg creatinine (1122-3575), p=0.001] but persisted significantly elevated respect to the levels of healthy controls (p<0.001). The effect of iloprost on oxidative stress appeared significant in patients with early and limited form of disease. CONCLUSIONS: This prospective open-label explorative study suggests that standard course of iloprost therapy may acutely reduce oxidative stress in SSc patients. This effect appears to be more consistent in the early phases and in the limited subset of disease. Further larger trials are needed to confirm our results and to explain the pathway of such reduction, its clinical significance and potential therapeutic implications.


Subject(s)
Iloprost/administration & dosage , Oxidative Stress/drug effects , Scleroderma, Systemic/drug therapy , Scleroderma, Systemic/metabolism , Vasodilator Agents/administration & dosage , Adult , Aged , Dinoprost/analogs & derivatives , Dinoprost/urine , Female , Humans , Male , Middle Aged , Prospective Studies
10.
Arch Intern Med ; 139(6): 698-9, 1979 Jun.
Article in English | MEDLINE | ID: mdl-443977

ABSTRACT

A 59-year-old woman was admitted to the hospital for evaluation of her hypertension. She was treated with hydralazine; two days later a severe acute hepatitis supervened. On discontinuation of the agent, the liver damage disappeared, relapsed during inadvertent rechallenge, and healed following permanent withdrawal from the drug. Histologic study of the liver showed severe acute hepatitis with bridging necrosis (so-called subacute hepatitis). Six months after discontinuation of hydralazine, a second liver biopsy specimen showed a complete remission of the disease. This hydralazine-induced hepatitis appears to be fully reversible and to differ both on clinical and histological grounds from two previous reports documenting a granulomatous liver disease.


Subject(s)
Chemical and Drug Induced Liver Injury/etiology , Hydralazine/adverse effects , Acute Disease , Chemical and Drug Induced Liver Injury/pathology , Female , Humans , Liver/pathology , Middle Aged , Necrosis
11.
Clin Pharmacol Ther ; 60(5): 576-81, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8941031

ABSTRACT

OBJECTIVE: To assess the results of a new immunosuppressive cycle, which had given favorable results in other immune-mediated glomerulonephritides, in the treatment of Henoch-Schönlein disease. METHODS: Eight patients (seven male and one female; age range, 13 to 61 years) with biopsy-proved Henoch-Schönlein were treated with the following protocol: (1) induction with 250 to 750 mg intravenous methylprednisolone every day for 3 to 7 days plus 100 to 200 mg oral cyclophosphamide every day, (2) maintenance with 100 to 200 mg oral prednisone on alternate days plus cyclophosphamide, as before, for 30 to 75 days; (3) tapering, with prednisone reduced on average by 25 mg every month while the cyclophosphamide dose remained the same, and (4) discontinuation, after at least 6 months, with abrupt interruption of cyclophosphamide and slow tapering of prednisone. The results were assessed in terms of remission, improvement, progression of disease, kidney failure, and death, unambiguously defined. The follow-up extended up to 12 years. RESULTS: Seven of eight patients had a complete remission that was maintained indefinitely thereafter. Plasma creatinine levels decreased on average from 211 +/- 81 to 92 +/- 27 mumol/L (p < 0.01) and urine protein excretion decreased from 1.9 +/- 0.8 to 0.3 +/- 0.1 gm/day (p < 0.01). One patient died of intestinal infarction caused by atherosclerotic mesenteric artery thrombosis. CONCLUSIONS: Our data suggest that an intensive immunosuppressive regimen that combines prednisone and cyclophosphamide at high doses can be effective in healing Henoch-Schönlein disease.


Subject(s)
Cyclophosphamide/therapeutic use , IgA Vasculitis/drug therapy , Immunosuppressive Agents/therapeutic use , Methylprednisolone/therapeutic use , Prednisone/therapeutic use , Administration, Oral , Adolescent , Adult , Drug Administration Schedule , Drug Therapy, Combination , Female , Humans , Injections, Intravenous , Male , Middle Aged , Remission Induction
12.
Clin Pharmacol Ther ; 60(5): 561-7, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8941029

ABSTRACT

BACKGROUND: The aim of our study was to determine whether immunosuppressive treatment is effective in preventing and reversing the evolution of Berger's disease toward chronic renal failure. METHODS: We studied 20 unselected, consecutive patients with biopsy-proven Berger's disease who met the criteria for disease progression. They had proteinuria, significant histologic changes, persistent hematuria, and red cell casts. The treatment consisted of prednisone in an alternate-day regimen and cyclophosphamide, either in a daily oral administration or in a monthly intravenous pulse injection, both given for a 6-month cycle. Five patients had chronic renal failure (as disclosed by plasma creatinine of 230 +/- 71 mumol/L), hypertension, and proteinuria (2.7 +/- 0.8 gm/day), whereas the remaining 15 patients had normal renal function (plasma creatinine, 97 +/- 18 mumol/L) and less severe proteinuria (1.9 +/- 1.1 gm/day). However, even these 15 patients had a significant number of risk factors heralding progression to chronic renal failure. RESULTS: Over an average follow-up of 8.7 +/- 3.7 years (range, 5 to 15 years), all patients but one had complete disease remission, including five patients with incipient chronic renal failure. Relapse occurred in two patients who were healed after a repeat treatment cycle. Over the entire follow-up period, no patient progressed to chronic renal failure and plasma creatinine concentration remained stable, even in subjects in whom it was high before treatment (257 +/- 79 versus 230 +/- 71 mumol/L; p > 0.05). CONCLUSION: The immunosuppressive treatment of patients with Berger's disease with high probability of progression appears to be effective in the prevention of end-stage renal disease.


Subject(s)
Cyclophosphamide/administration & dosage , Glomerulonephritis, IGA/drug therapy , Immunosuppressive Agents/administration & dosage , Kidney Failure, Chronic/prevention & control , Prednisone/administration & dosage , Adolescent , Adult , Drug Administration Schedule , Drug Therapy, Combination , Female , Glomerulonephritis, IGA/blood , Humans , Male , Middle Aged , Remission Induction
13.
Br J Pharmacol ; 76(3): 357-60, 1982 Jul.
Article in English | MEDLINE | ID: mdl-6809089

ABSTRACT

1 The relative importance of the effect of prostaglandins on renal sodium and water reabsorption was assessed in rats. 2 Clearance experiments were performed on 24 anaesthetized rats divided into 3 groups. Each group was infused throughout either with Ringer solution at 9 ml/h (Protocol I), or at 3 ml/h (Protocol II) or with hypotonic fluid at 5 ml/h (Protocol III). Clearance periods were performed before and after intravenous injection of indomethacin (5 mg/kg) and then of aspirin (20 mg/kg). The natriuretic response to different degrees of volume expansion was not modified during the action of the inhibitors. 3 When baseline urine osmolality (Uosm) was high (Protocol II) no further increase occurred in the presence of prostaglandin inhibition. Conversely, Uosm rose from 771 +/- 134 to 1356 +/- 414 and from 575 +/- 245 to 841 +/- 407 mosm/kg (P less than 0.05) in Protocol I and Protocol III respectively, when antidiuretic hormone secretion was inhibited by the higher degree of volume expansion. 4 There was a significant correlation between the change in urine flow rate induced by cyclooxygenase inhibitors and the attendant variations in Na excretion, r = 0.42, n = 41, P less than 0.01. 5 Thus, prostaglandins affect Na loss during saline load as a side effect of their action on water permeability. They could play an important role in volume depletion by counterbalancing the large secretion rate of renal vasoconstrictors.


Subject(s)
Body Water/metabolism , Cyclooxygenase Inhibitors , Kidney/physiology , Prostaglandins/pharmacology , Sodium/metabolism , Absorption , Animals , Rats
14.
J Clin Pharmacol ; 19(11-12): 751-7, 1979.
Article in English | MEDLINE | ID: mdl-536472

ABSTRACT

Forty-three patients suffering from hypertension of different origin (chronic renal failure, gout, or idiopathic) were treated with propranolol (121 +/- 12 mg q.d.) plus hydrochlorothiazide (50 mg q.d.) for 75 +/- 9 days. Blood pressure did not return to normal limits in 15 patients, who were continued on the same protocol plus 10 to 50 mg oxdralazine q.d. After an average of 68 +/- 35 days blood pressure fell from 180/110 mm Hg to 145/90 mm Hg without orthostatism, significant side effects, or changes in GFR. This combination seems particularly successful since propranolol will prevent the undesired rise in cardiac output due to oxdralazine as well as the activation of the renin-angiotensin axis due to diuretics. Thus, the antihypertensive properties of each agent will be enhanced by a reduction in side effects by the associated drug, resulting in optimal blood pressure control.


Subject(s)
Ethanolamines/therapeutic use , Hydrochlorothiazide/therapeutic use , Hypertension/drug therapy , Propranolol/therapeutic use , Pyridazines/therapeutic use , Vasodilator Agents/therapeutic use , Adult , Aged , Blood Pressure/drug effects , Drug Therapy, Combination , Ethanolamines/administration & dosage , Female , Glomerular Filtration Rate , Heart Rate/drug effects , Humans , Hydrochlorothiazide/administration & dosage , Male , Middle Aged , Propranolol/administration & dosage , Pyridazines/administration & dosage , Vasodilator Agents/administration & dosage
15.
J Clin Pharmacol ; 20(7): 452-8, 1980 Jul.
Article in English | MEDLINE | ID: mdl-6776160

ABSTRACT

Experiments were performed on humans to study the blunting on the diuretic action of furosemide by prostaglandin synthetase inhibitors. Maximal water diuresis was instituted. At the peak of urine flow, clearance periods were performed during baseline conditions and repeated after the injection of aspirin and, subsequently, of furosemide. Control subjects did not receive aspirin. Urine flow rate (V), Cosm, and Na excretion (UNa) . V were significantly lower when the administration of the diuretic had been preceded by that of aspirin. In the absence of furosemide, however, aspirin did not influence renal hemodynamics nor Na and water reabsorption. Therefore, the same experimental protocol was repeated in paired experiments where each normal subject served as his own control, being studied twice, in the presence and absence of aspirin, respectively. The average changes in water and Na excretion induced by furosemide were not different when the patients were pretreated with aspirin as compared with those measured in the absence of prostaglandin inhibition. Changes occurring in individual experiments were significantly correlated (r = 0.95, P less than 0.01) with those in calculated furosemide clearance. Since aspirin, indomethacin, and meclophenamate are secreted by the organic acid transport system of the proximal tubule, competition for a common secretory mechanism, rather than prostaglandin inhibition, could mediate the blunting of furosemide diuresis.


Subject(s)
Aspirin/pharmacology , Diuresis/drug effects , Furosemide/antagonists & inhibitors , Cyclooxygenase Inhibitors , Drug Interactions , Furosemide/metabolism , Furosemide/pharmacology , Metabolic Clearance Rate/drug effects , Time Factors
16.
Clin Exp Rheumatol ; 19(2): 125-30, 2001.
Article in English | MEDLINE | ID: mdl-11326473

ABSTRACT

OBJECTIVE: Several investigations indicate that glycosaminoglycans (GAG) are important components of the glomerular basement membrane (GBM) and that they play a remarkable role in the control of charge-selectivity in the glomerular capillary wall. In order to evaluate the possible use of GAG as a marker of glomerular disease, we evaluated urinary GAG excretion in 37 patients with systemic lupus erythematosus (SLE) grouped by disease activity and kidney involvement and in 17 healthy controls. METHODS: GAG were isolated from urine by using ion-exchange chromatography on DEAE Sephacel. GAG composition was determined by cellulose acetate electrophoresis and expressed as relative percentages by densitometric scanning of Alcian Blue stained strips. RESULTS: Total GAG levels were significantly increased only in active extra-renal SLE patients. Qualitative analysis of urinary GAG revealed the presence of a low sulphated chondroitin sulphate-protein complex (LSC-PG), whose frequency was higher in patients compared to controls. Moreover, inactive SLE was characterized by an alteration of the chondroitin sulphate/heparan sulphate ratio. CONCLUSION: These variations suggest the presence of an abnormal permeability of the renal filter in patients without other appreciable signs of kidney alteration. Therefore, qualitative-quantitative urinary GAG analysis could represent an additional diagnostic approach.


Subject(s)
Chondroitin Sulfates/urine , Heparitin Sulfate/urine , Lupus Erythematosus, Systemic/diagnosis , Lupus Erythematosus, Systemic/urine , Adolescent , Adult , Albuminuria/urine , Biomarkers , Chromatography, Ion Exchange , Diuresis , Female , Hexuronic Acids/urine , Humans , Male , Middle Aged
17.
J Nephrol ; 12(1): 47-50, 1999.
Article in English | MEDLINE | ID: mdl-10203004

ABSTRACT

The present study was designed to elucidate the relationship between endolymphatic pressure and plasma ADH levels in conscious guinea pigs. Plasma ADH (pADH) was measured in basal conditions and after having applied positive or negative pressure of 20 cmH2O to the inner ear. The experimental protocol was designed to avoid any interference on ADH release caused by anesthesia and surgical stress. There was no change in blood pressure, heart rate, plasma Na (pNa) and osmolality (pOsm) after inner ear pressure (IEP) modifications. However, pADH was inversely related with IEP: pADH averaged 31.4 +/- 7.0 pg/ml (mean +/- S.D.) in basal conditions, rising to 48.8 +/- 19.3 when IEP was lowered and falling to 16.6 +/- 10.3 when IEP was raised. These results confirm that structures in the inner ear help control of ADH release.


Subject(s)
Ear, Inner/physiology , Endolymph/physiology , Vasopressins/blood , Animals , Guinea Pigs , Male , Osmolar Concentration , Pressure , Sodium/blood , Vasopressins/metabolism
18.
Panminerva Med ; 34(2): 85-92, 1992.
Article in English | MEDLINE | ID: mdl-1408334

ABSTRACT

The basic tubular alteration present in Bartter's syndrome is still a subject of controversy. The possibility that a generalized defect in transmembrane ion transport underlies the disease has been extensively investigated. Previous evaluations of cellular sodium metabolism in Bartter's patients showed extremely variable findings. In the present study we have examined in red blood cells of two patients with Bartter's syndrome the intracellular Na+ and K+ concentrations, the activity of ouabain-sensitive Na+/K+ pump, furosemide sensitive Na+/K+ cotransport, Na+/Li+ countertransport, and the rate constant of Na+ and K+ passive permeability. We have compared these values with those of a control group. Ouabain-sensitive Na+/K+ pump activity was decreased in both patients, whereas Na+/Li+ countertransport was activated. One of the patients also exhibited markedly decreased intraerythrocyte K+ concentration and decreased furosemide-sensitive Na+/K+ cotransport. The other had increased Na+/K+ cotransport activity and Na+ passive permeability. Intracellular Na+ and passive permeability to K+ were normal in both subjects. Our results are partially consistent with previously reported observations, and indicate the existence of heterogeneous alterations of erythrocyte sodium transport systems in patients with Bartter's syndrome. Although some of these alterations could be secondary to the electrolyte metabolism derangements of this disease, others might be genetically transmitted and could cause the different renal tubular defects shown in Bartter's disease so far.


Subject(s)
Bartter Syndrome/metabolism , Sodium/metabolism , Adult , Erythrocyte Membrane/metabolism , Female , Humans , Ion Transport , Kidney Tubules/metabolism , Male , Potassium/metabolism
19.
Clin Nephrol ; 46(4): 237-44, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8905208

ABSTRACT

To assess the effectiveness of an intensive immunosuppressive regimen on the nephrotic syndrome due to mixed membranous and mesangial lesions, we studied 18 patients with nephrotic syndrome and miscellaneous histologic features characterized by mesangial proliferation and sclerosis, non-specific basement membrane changes such as thickening, fraying and scalloping, in the absence of extensive immune complex deposition by immunofluorescence. The patients were treated with an immunosuppressive regimen that combined prednisone and cyclophosphamide for at least 6 months with the following schedule: 1) induction with prednisone daily 250 to 750 mg i.v. for 3 to 8 days, plus cyclophosphamide 100 to 200 mg p.o. daily; 2) maintenance with prednisone 100 to 200 mg p.o. in alternate days for 30 to 75 days, and cyclophosphamide as before; 3) tapering, with prednisone in alternate day regimen, reduced on average by 25 mg every month, plus cyclophosphamide as before; 4) discontinuation of cyclophosphamide and slow withdrawal of prednisone. Treatment lasted on average 9 months, with an average cumulative dose of prednisone of 9.2 g and of cyclophosphamide of 26.7 g. At the end of treatment, 14 patients had a complete remission and 4 remained stable. On longer follow-up, one out of these 4 patients, who had renal failure before treatment, subsequently progressed to end-stage renal disease. Nine patients relapsed after an average remission of 6 years. Eight of them remitted completely on a repeat cycle. One patient refused the retreatment and progressed to end-stage renal disease within one year. After an average follow-up of 7.3 +/- 1.1 years, plasma creatinine for the whole group had fallen from 138 +/- 26 to 103 +/- 20 mumol/l and proteinuria from 6.7 +/- 0.7 to 0.4 +/- 0.2 g/d (p < 0.001). In conclusion, in patients with these forms of nephrotic syndrome this immunosuppressive regimen is highly effective in inducing remission, in preventing progression to end-stage renal disease and in treating relapses.


Subject(s)
Cyclophosphamide/therapeutic use , Immunosuppressive Agents/therapeutic use , Nephrotic Syndrome/drug therapy , Nephrotic Syndrome/etiology , Prednisone/therapeutic use , Adult , Biopsy , Disease Progression , Drug Therapy, Combination , Female , Follow-Up Studies , Glomerular Mesangium/pathology , Glomerulonephritis, Membranoproliferative/complications , Glomerulonephritis, Membranoproliferative/pathology , Humans , Kidney Failure, Chronic/prevention & control , Male , Nephrotic Syndrome/pathology , Recurrence , Time Factors
20.
Clin Nephrol ; 44(6): 367-75, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8719548

ABSTRACT

To evaluate the results, the long-term prognosis and the rates of complication of an immunosuppressive regimen with corticosteroids and cyclophosphamide in the treatment of the nephritis of systemic lupus erythematosus, 21 patients with lupus glomerulonephritis were studied. Renal biopsies were performed in 17/21 of them and indicated diffuse proliferative (6 patients), diffuse mesangial (4) and membranous (7) glomerulonephritis. Treatment was structured in 4 phases: 1) induction with methylprednisolone 250 mg i.v. for 7-14 days, and cyclophosphamide 100-200 mg p.o., q.d., or 20 mg/kg i.v. every 28 days; 2) maintenance with prednisone p.o., 2 mg/kg q.o.d. for 45 days, and cyclophosphamide as before; 3) tapering, with reduction of prednisone by 15% each month for 4 months; 4) indefinite maintenance with prednisone slowly tapered to the least effective q.o.d. dose and cyclophosphamide discontinued after six months of treatment. This cycle was repeated in the event of a relapse. After a first immunosuppressive cycle, 20/21 patients achieved remission of glomerulonephritis. Plasma creatinine fell from 97 +/- 6 to 80 +/- 3 microMol/l (p < 0.01). Proteinuria fell from 2.1 +/- 0.4 to 0.2 +/- 0.4 g/d (p < 0.0001) and the nephrotic syndrome, present in 8 patients, disappeared. After an average of 20 +/- 7 months, 8 patients relapsed: all remitted again after a repeat cycle, but 1 later progressed to end-stage renal failure during pregnancy. After an average of 56 months 4 out of these 8 patients relapsed again: 1 progressed to end-stage renal disease following an abortion and 3 remitted completely after a third cycle. Thus, 18 out of 21 patients are presently in remission with an average dose of prednisone of 13.7 mg/day after an average follow-up of 52 +/- 38 months (range 2 to 156). Three patients are presently off treatment. In 16 patients with extended follow-up of 2 to 13 years, anti-nuclear antibodies, anti-DNA antibodies, albuminuria and cylindruria fell below post-cycle levels (p < 0.001 for all). We conclude that intensive immunosuppression with steroids and cyclophosphamide can achieve excellent long-term results in the treatment of systemic lupus with glomerulonephritis.


Subject(s)
Adrenal Cortex Hormones/therapeutic use , Cyclophosphamide/therapeutic use , Immunosuppressive Agents/therapeutic use , Lupus Nephritis/drug therapy , Adult , Aged , Biopsy , Drug Therapy, Combination , Female , Follow-Up Studies , Humans , Kidney Failure, Chronic/etiology , Kidney Failure, Chronic/pathology , Lupus Nephritis/complications , Lupus Nephritis/pathology , Male , Pregnancy , Proteinuria/complications , Proteinuria/drug therapy , Proteinuria/pathology , Recurrence , Remission Induction , Treatment Outcome
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