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1.
Fungal Syst Evol ; 7: 99-111, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34124619

RESUMO

Crown decline and mortality associated with collar lesions were observed on Carya cathayensis (Chinese hickory) trees in a plantation in Zhejiang province, China. Examination of active lesions resulted in the isolation of a homothallic, papillate Phytophthora sp. Detailed morphological and physiological studies and phylogenetic analysis, using ITS, beta-tubulin, cytochrome oxidase I, and heat shock protein 90 gene regions, revealed that all isolates belonged to an undescribed species residing in phylogenetic Clade 4, which is described here as Phytophthora cathayensis sp. nov. Inoculation trials were conducted under greenhouse conditions on C. cathayensis and C. illinoensis (pecan) plants to fulfill Koch postulates and hypothesize a possible pathway of the incursion. An existing report of a Phytophthora species with the same ITS sequence was reported on C. illinoensis from the USA in 2009. The difference in susceptibility of the two inoculated Carya species, and the report from the USA, suggest a possible introduction with plant material from the USA to China. Citation: Morales-Rodríguez C, Wang Y, Martignoni D, Vannini A (2020). Phytophthora cathayensis sp. nov., a new species pathogenic to Chinese Hickory (Carya cathayensis) in southeast China. Fungal Systematics and Evolution 7: 99-111. doi: 10.3114/fuse.2021.07.05.

2.
Plant Dis ; 100(2): 324-330, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30694134

RESUMO

The efficacy of biofumigation with Brassica carinata pellets (BioFence) to control vegetative and reproductive structures of Phytophthora cinnamomi was investigated in vitro at different doses and temperatures. Biofumigation was effective in inhibiting mycelial growth (culture diameter) and chlamydospore and zoospore germination, and was lethal at 24 mg of pellet per plate (approximately 0.4 mg/liter). The 50% effective concentration values showed that efficacy of B. carinata pellets in inhibiting or killing the vegetative and reproductive structures of P. cinnamomi was maximum at 15°C and decreased as temperature rose to 25°C. However, the fungicide effect was independent of the temperature. In vivo biofumigation of Quercus cerris seedlings with BioFence confirmed efficacy by reducing the inoculum density (CFU/g) of P. cinnamomi, thus protecting the host from root infection. The use of BioFence provides an alternative to synthetic pesticides to control P. cinnamomi within disease management programs in agroforestry systems.

3.
Plant Dis ; 99(8): 1133-1139, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30695936

RESUMO

Phytophthora lateralis, the cause of Chamaecyparis lawsoniana root disease, was introduced in North America about 1920, and has since killed trees along roads and streams throughout the tree's range. Recent results suggest an Asian origin for this oomycete and four genetic lineages were identified. This raised questions for the genetic exapted resistance demonstrated in 1989 within the wild population of C. lawsoniana but with only one P. lateralis lineage. The main goal of the present research was to test the durability of the demonstrated resistance and to compare the pathogenicity of isolates representing the four lineages. No breakdown of resistance was observed in five separate tests using different inoculation techniques, resistant and susceptible C. lawsoniana trees, and seedling families. Differences in mortality and lesion length were observed between the lineages. The higher aggressiveness of isolates of the TWJ and PNW lineages and the lower aggressiveness of the TWK lineage are discussed in view of the hypotheses on the history of spread and evolutionary history of the P. lateralis lineages.

4.
New Phytol ; 197(1): 238-250, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23057437

RESUMO

A large database of invasive forest pathogens (IFPs) was developed to investigate the patterns and determinants of invasion in Europe. Detailed taxonomic and biological information on the invasive species was combined with country-specific data on land use, climate, and the time since invasion to identify the determinants of invasiveness, and to differentiate the class of environments which share territorial and climate features associated with a susceptibility to invasion. IFPs increased exponentially in the last four decades. Until 1919, IFPs already present moved across Europe. Then, new IFPs were introduced mainly from North America, and recently from Asia. Hybrid pathogens also appeared. Countries with a wider range of environments, higher human impact or international trade hosted more IFPs. Rainfall influenced the diffusion rates. Environmental conditions of the new and original ranges and systematic and ecological attributes affected invasiveness. Further spread of established IFPs is expected in countries that have experienced commercial isolation in the recent past. Densely populated countries with high environmental diversity may be the weakest links in attempts to prevent new arrivals. Tight coordination of actions against new arrivals is needed. Eradication seems impossible, and prevention seems the only reliable measure, although this will be difficult in the face of global mobility.


Assuntos
Bases de Dados Factuais , Fungos/patogenicidade , Espécies Introduzidas , Árvores/microbiologia , Clima , Ecossistema , Europa (Continente) , Fungos/classificação , Fungos/fisiologia , Geografia , Modelos Lineares , Doenças das Plantas/microbiologia , Densidade Demográfica , Análise de Componente Principal , Chuva , Fatores Socioeconômicos , Temperatura , Fatores de Tempo , Árvores/fisiologia
5.
Lett Appl Microbiol ; 55(5): 390-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25998830

RESUMO

AIMS: To evaluate the accuracy of pyrosequencing for the description of Phytophthora communities in terms of taxa identification and risk of assignment for false Molecular Operational Taxonomic Units (MOTUs). METHODS AND RESULTS: Pyrosequencing of Internal Transcribed Spacer 1 (ITS1) amplicons was used to describe the structure of a DNA mixture comprising eight Phytophthora spp. and Pythium vexans. Pyrosequencing resulted in 16 965 reads, detecting all species in the template DNA mixture. Reducing the ITS1 sequence identity threshold resulted in a decrease in numbers of unmatched reads but a concomitant increase in the numbers of false MOTUs. The total error rate was 0·63% and comprised mainly mismatches (0·25%) CONCLUSIONS: Pyrosequencing of ITS1 region is an efficient and accurate technique for the detection and identification of Phytophthora spp. in environmental samples. However, the risk of allocating false MOTUs, even when demonstrated to be low, may require additional validation with alternative detection methods. SIGNIFICANCE AND IMPACT OF THE STUDY: Phytophthora spp. are considered among the most destructive groups of invasive plant pathogens, affecting thousands of cultivated and wild plants worldwide. Simultaneous early detection of Phytophthora complexes in environmental samples offers an unique opportunity for the interception of known and unknown species along pathways of introduction, along with the identification of these organisms in invaded environments.


Assuntos
DNA Espaçador Ribossômico/genética , Phytophthora/classificação , Pythium/classificação , Pythium/genética , Técnicas de Tipagem Bacteriana , Sequência de Bases , Micélio/crescimento & desenvolvimento , Phytophthora/genética , Phytophthora/isolamento & purificação , Doenças das Plantas/microbiologia , Plantas/microbiologia , Pythium/isolamento & purificação , Análise de Sequência de DNA/métodos
6.
Oncol Res ; 20(5-6): 259-64, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23581233

RESUMO

Sunitinib, an orally multitargeted tyrosine kinase inhibitor and standard first-line treatment for metastatic renal cell carcinoma, is usually administered on a 6-week schedule. Toxicities reported with this drug are usually of moderate grade, which results in good treatment tolerability and patients' compliance. However, in some cases high-grade or prolonged toxicities require temporary treatment interruption or dose adjustment, possibly resulting in reduced treatment efficacy. We describe three cases of metastatic renal cell carcinoma patients (a 53-year-old male, a 70-year-old woman, and a 65-year-old woman) who received a shortened 3-week sunitinib administration schedule, 2 weeks daily administration followed by 1 week of rest (2/1) due to toxicities developed on the classic 6-week schedule, which would have required a temporary treatment interruption or a dose reduction. Treatment was generally well tolerated with manageable toxicities. A 3-week administration schedule of sunitinib may represent a valid alternative for managing toxicity while maintaining the planned dose intensity over a 6-weeks period of time. Sunitinib may thus be administered using a flexible dosing schedule to meet individual patient needs, achieving better tolerability and maintaining significant response to treatment.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Indóis/administração & dosagem , Neoplasias Renais/tratamento farmacológico , Pirróis/administração & dosagem , Idoso , Antineoplásicos/efeitos adversos , Carcinoma de Células Renais/patologia , Esquema de Medicação , Feminino , Humanos , Indóis/efeitos adversos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Pirróis/efeitos adversos , Sunitinibe
7.
Anticancer Res ; 30(12): 5169-73, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21187507

RESUMO

BACKGROUND: The activity of sunitinib, a multitargeted tyrosine kinase inhibitor with antiangiogenic and antitumor activities, has been explored in several solid malignancies such as breast, lung, prostate and pancreatic cancer. Currently it is approved for the treatment of metastatic renal cell carcinoma and gastrointestinal stromal tumors. Non-small cell lung cancer usually presents at an advanced or metastatic stage at diagnosis. Treatment options are limited for this disease, therefore symptom palliation and patient's quality of life are primary objectives of therapy. CASE REPORT: We describe the case of a patient (male, 67 years old) with heavily pre-treated metastatic non-small cell lung carcinoma who received sunitinib according to the following 3-week schedule: 50 mg daily for 2 weeks followed by a 1-week rest. The patient completed six months of therapy achieving a major disease response without high-grade toxicities. CONCLUSION: In this case, sunitinib shows promising single-agent activity in pretreated non-small cell lung cancer, with a good toxicity profile and flexible administration schedule.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Indóis/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Pirróis/administração & dosagem , Idoso , Antineoplásicos/efeitos adversos , Esquema de Medicação , Humanos , Indóis/efeitos adversos , Masculino , Pirróis/efeitos adversos , Sunitinibe
8.
Plant Dis ; 94(2): 272, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30754294

RESUMO

Boxwood (Buxus spp.) includes several species of popular ornamental shrubs used in traditional and contemporary gardening. In March of 2008, a gradual and irreversible decline was observed on 6-year-old Buxus rotundifolia plants in a garden in central Italy. Of 150 boxwood plants, 70% were symptomatic, and among them, approximately 25% were completely wilted. Aboveground symptoms included stunting, necrotic bark lesions at the base of the stem, reduced growth, and leaf chlorosis. Leaves at first appeared light green, then turned yellow, bronze, or straw colored. Foliar symptoms were restricted to a few branches or extended to the whole crown. Immunological field tests (Pocket Diagnostic, CSL Diagnostics, Milan, Italy) on necrotic rootlets and bark tissues suggested the risk of the presence of Phytophthora spp. One species was consistently isolated on PARHP (2) from necrotic tissues of three symptomatic plants. Recovered isolates were heterothallic and produced aerial mycelium. Star-like compact growth was also observed on potato dextrose agar. Cultures on carrot agar submerged in saline solution (2) developed papillate, noncaducous, and sympodially branched sporangia of different shapes ranging from ovoid to obturbinate. Sporangia were 37.5 to 65.0 × 22.5 to 35.0 µm (average 49.0 × 31.0 µm); L/W ratio from 1.1 to 2.1 (average 1.6). On the basis of morphological features, these isolates belong to P. citrophthora (R.E. Sm. & E.H. Sm.) Leonian (2). The identity was confirmed by sequencing of the internal transcribed spacer region of the rDNA (NCBI Accession No. FJ874794). Inoculum for two isolates of P. citrophthora (3BO and 4BO) was produced for pathogenicity testing on 100 g of autoclaved millet grains moistened with 70 ml of V8 juice. Two, 2-liter aliquots of potting media were each amended with the infested grains (1:20 vol/vol) and five 3-year-old plants of B. rotundifolia per isolate were transplanted into the media. Plants were maintained in a growth chamber at 18 to 22°C, with relative humidity of 80%, and a 12-h photoperiod. Sterile millet grains were used to inoculate five boxwood plants for the control. After 2 months, control plants remained healthy while inoculated plants displayed root necroses and foliar symptoms similar to those observed in the field. The pathogen, consistently reisolated from roots of infected plants, reduced the root weight by an average of 25%. Root rot of boxwood plants is reported to be caused by P. citricola in Poland (4), P. parasitica in Virginia (3), and P. citrophthora in North Carolina (1). To our knowledge, this is the first report of P. citrophthora on B. rotundifolia in Europe. References: (1) Z. G. Abad et al. Plant Dis. 78:830, 1994. (2) D. C. Erwin and O. K. Ribeiro. Page 562 in: Phytophthora Diseases Worldwide. The American Phytopathological Society. St. Paul, MN, 1996. (3) M. A. Hansen. Plant Dis. Fact Sheets. 450-614W, 2000. (4) L. B. Orlikowski. J. Plant Prot. Res. 46:163, 2006.

9.
Oncol Res ; 17(11-12): 559-64, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19806786

RESUMO

Single-agent gemcitabine has been established as standard treatment for advanced pancreatic cancer since clinical studies have shown an improvement in overall survival and significant clinical benefit when compared to the best supportive care despite low overall objective response. Several phase II studies have tested other single agents and different gemcitabine-based regimens in pancreatic cancer, but both response and survival rates have remained low. Irinotecan, a topoisomerase I inhibitor currently approved for the treatment of metastatic colon cancer, has also demonstrated improved response rate in patients with pancreatic cancer. Our purpose was to determine the activity and toxicity of this regimen in patients with unresectable or metastatic pancreatic cancer. Patients with histologically confirmed pancreatic adenocarcinoma received gemcitabine 1000 mg/m2 plus irinotecan 100 mg/m2 IV on days 1, 8, and 15 of a 28-day cycle for 6-8 months. From February 2004 to April 2006, 33 patients were entered into this study, 32 of whom were evaluable for treatment response, toxicity, median time to progression, and median survival. Characteristics included a median age of 63 years (range 41-79), 21 males (64%), and 12 females (36%). One patient discontinued treatment due to adverse effects. The total number of cycles administered was 188 and the median number of cycles for patients was 5.6 (range 2-7). Thirty-two patients were assessable for toxicity and response. Grade 3 hematological toxicity occurred in 9% of patients and was primarily neutropenia. No grade >2 gastrointestinal toxicities or death due to treatment were observed. The most frequent nonhematological adverse event was fatigue. Ten patients responded to treatment with two complete responses (6.3%) and eight partial responses (25.0%), for an overall response rate of 31.3%; 11 patients achieved stable disease (34.3%). The median time to tumor progression and the median survival were 9.2 (95% CI: 6.0-12.4) and 11.8 (95% CI: 7.7-15.9) months, respectively, with a 2-year survival of 22%. On the basis of this trial, the combination of gemcitabine plus irinotecan, administered in a weekly schedule and at this dose, is well tolerated and offers encouraging activity in the treatment of advanced and/or metastatic pancreatic cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/mortalidade , Adulto , Idoso , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Feminino , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Gencitabina
10.
Plant Dis ; 93(2): 200, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30764117

RESUMO

Leaf drop, wilt, and mortality were observed in September of 2007 on approximately 10% of 1- to 2-year-old olive (Olea europaea cv. Leccino) plants shipped from Europe and growing in a nursery in the District of Makwampur, Nepal. Roots of symptomatic and asymptomatic plants were disinfected in 1% NaOCl, cut into 1 cm long pieces, plated on 2% potato dextrose agar, and maintained at 20°C with 14 h of light per day. Colonies with white mycelium developed after 3 days. Microconidia and three-septated macroconidia averaged 11 × 3.9 µm and 38 × 5 µm, respectively. Chlamydospores were produced singly and in pairs. On the basis of culture characteristics, the fungus was identified as Fusarium solani (2). The ITS1-5.8S-ITS2 DNA sequences of 10 monoconidial cultures shared 99% identity with F. solani strains available on the NCBI databases (GenBank Accession Nos. 1115947 and 1115999). Pathogenicity tests were conducted with F. solani isolates NR1 and NR2 obtained from symptomatic plants. Twelve-month-old rooted cuttings of O. europaea cv. Leccino were transferred to pots containing a soilless mix and F. solani-infected oat grains (10:1 vol/vol). Fifteen plants of each F. solani isolate were inoculated. Noninfested sterilized oat grains were used for the control treatment. Symptoms on inoculated plants included leaf abscission followed by wilting and plant death approximately 10 days after inoculation and resembled those observed on the naturally infected plants. Noninoculated control plants remained healthy. The fungus was reisolated from roots of symptomatic tissues and was identical in appearance to the isolates used to inoculate the plants. No colonies of F. solani were isolated from noninoculated plants. F. solani has been reported as weakly pathogenic on olive in Spain (4) and highly aggressive on olive in Argentina (1) and India (3). To our knowledge, this is the first report of F. solani causing wilt and mortality of young olive plants in Nepal. References: (1) S. Babbit et al. Plant Dis. 86:326, 2002. (2) C. Booth. Fusarium Laboratory Guide to the Identification of the Major Species. CMI, Kew, England, 1977. (3) R. L. Munjal et al. Studies on diseases of olive in Himachal Pradesh. Page 437 in: Improvement of Forest Biomass. Symposium Proceedings. Indian Society of Tree Scientists. P. K. Kosla, ed. Sdan, India, 1982. (4) M. E. Sánchez Hernández et al. Eur. J. Plant Pathol. 104:347, 1998.

11.
Plant Dis ; 93(7): 765, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30764371

RESUMO

In Argentina, olives (Olea europaea) are planted on approximately 90,000 ha located primarily in the northwest continental regions. During a 2005 survey, root rot was recorded at several olive plantations in Catamarca, La Rioja, and San Juan provinces (3). Aboveground symptoms associated with root rot were twigs wilting with or without chlorosis, defoliation, and death. Symptoms were initiated on lateral branches and sometimes affected the entire crown. Even if young (5-year-old) trees displayed root rot, aerial symptoms may or may not be seen until years later. Disease incidence varied from 3 to 30%. Rotted rootlets were associated mainly with the infection of Phytophthora palmivora Butler and less frequently with another Phytophthora species. Isolates of this species were heterothallic, had a fluffy growth on carrot agar, and arachnoid growth on potato dextrose agar. Chlamydospores approximately 36 µm in diameter were also produced. The species developed prominent, papillate, noncaducous sporangia of different shapes ranging from ellipsoid to spherical when submerged in saline solution. Sporangia were 35 to 57 × 25 to 45 µm (average 44 × 33 µm), L:B ratio from 1.1 to 1.7. Isolates formed oogonia and amphyginous antheridia following mating type assays. On the basis of morphological features, these isolates were identified as P. nicotianae Breda de Haan. Identity was confirmed by sequencing the rDNA internal transcribed spacer (GenBank Accession No. FJ746693) (1). One-year-old O. europea seedlings were challenged with P. nicotianae (A1 isolates 306G and 339) through soil infestation assay in a growth chamber at 25°C. Infested and uninfested autoclaved millet grains moistened with V8 juice were used to inoculate 15 olive seedlings per isolate and controls, respectively. Fifty days after inoculation, seedlings showed foliar symptoms similar to those observed in the field and had an average of 50% reduction in the root system. Control plants remained healthy. P. nicotianae was always reisolated from symptomatic roots. P. nicotianae was reported on Citrus aurantium in Argentina in 1947 and is currently associated with several hosts (2). In 2002, the same species was reported associated with olive root rot in southern Italy (4). It is possible that P. nicotianae was recently introduced into Argentina through importation of Mediterranean olive varieties. The demonstrated pathogenicity of P. nicotianae on olive together with the recently reported detection of P. palmivora (3) presents a serious threat to olive cultivation in Argentina. References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) M. J. Frezzi. Rev. Investig. Agric. 4:47, 1950. (3) G. Lucero et al. Plant Pathol. 56:728, 2007. (4) F. Nigro and A. Ippolito. Acta Hortic. 586:777, 2002.

12.
Annu Rev Biophys ; 37: 337-52, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18573085

RESUMO

The eukaryotic RNA polymerases Pol I, Pol II, and Pol III are the central multiprotein machines that synthesize ribosomal, messenger, and transfer RNA, respectively. Here we provide a catalog of available structural information for these three enzymes. Most structural data have been accumulated for Pol II and its functional complexes. These studies have provided insights into many aspects of the transcription mechanism, including initiation at promoter DNA, elongation of the mRNA chain, tunability of the polymerase active site, which supports RNA synthesis and cleavage, and the response of Pol II to DNA lesions. Detailed structural studies of Pol I and Pol III were reported recently and showed that the active center region and core enzymes are similar to Pol II and that strong structural differences on the surfaces account for gene class-specific functions.


Assuntos
RNA Polimerases Dirigidas por DNA , Modelos Químicos , Modelos Genéticos , RNA/biossíntese , RNA/química , Transcrição Gênica/genética , Animais , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/ultraestrutura , Ativação Enzimática , Humanos , Modelos Moleculares , RNA/genética
13.
Plant Dis ; 92(12): 1708, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30764314

RESUMO

During 2006 and 2007, declining mature beech trees (Fagus sylvatica) were recorded in two stands in the Natural Park of Monti Cimini in central Italy. Symptoms included crown thinning and the presence of bleeding lesions on the main roots and lower stem. Incidence of decline was approximately 5%. Samples of necrotic bark tissue were collected, cut into 5 mm long segments, plated on PARPNH, and incubated at 20°C (1). Phytophthora isolates were obtained from necrotic tissues of 25% of the sampled declining trees. Colonies were rosaceous on potato dextrose agar (PDA) and homothallic. Papillate, ovoid-to-obpyriform, caducous sporangia (mean 38 × 26.2 µm) were produced in soil extract. Oospores were plerotic (mean diameter of 22 to 32 µm) and antheridia paragynous. Optimum growth temperature was 23 to 25°C, minimum 6 to 8°C and maximum 30 to 33°C. A portion of the internal transcribed spacer sequence has been deposited in the NCBI database (GenBank Accession No. FJ183724). A BLAST search of the NCBI database revealed Phytophthora cactorum, Accession No. EU194384, as the closest match with 100% sequence similarity. Pathogenicity of two isolates, PFE3 and IFB-CAC 38, collected from distressed beech trees was tested using a soil infestation test (10 beech seedlings per isolate and control) and an under the bark inoculation method (10 twigs per isolate and controls, wounded and noninoculated taken from a declining beech tree) (2). After 2 weeks at 20°C, twigs and seedlings inoculated with each isolate developed extensive necrotic lesions around the inoculation sites and the collar, respectively, and P. cactorum could be reisolated from all lesions. Controls showed no symptoms. P. cactorum is widespread in declining beech forests in central Europe (1). In Italy, P. cactorum occurs in soils of chestnut and oak forests and was isolated from collar and root lesions of declining walnut trees (3). To our knowledge, this is the first report of P. cactorum being associated with declining beech trees in Italy. References: (1) T. Jung. Forest Pathol. Online publication. doi:10.1111/j.1439-0329.2008.00566.x, 2008. (2) T. Jung et al. Eur. J. For. Pathol. 26:253, 1996. (3) A. M. Vettraino et al. Plant Pathol. 52:491, 2003.

14.
Plant Dis ; 92(1): 177, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30786376

RESUMO

Sweet cherry (Prunus avium L.) cultivation has increased in Italy and ≈30,000 ha are now in production. In the spring of 2006, a disease survey was conducted in orchards of central Italy. Decline symptoms of Prunus avium 'Durone' grafted on wild rootstocks of Prunus avium consisted of reduced tree vigor, yellowing of leaves, and development of root and collar rot. A reddish brown discoloration of the inner bark and wood was observed on symptomatic trees. Symptoms were recorded in three cherry orchards seasonally submitted to soil saturation conditions. In one orchard, symptoms were observed on approximately 30% of 170 surveyed trees. A Phytophthora species was consistently isolated on PARPH-V8 medium (2) from collar lesions of five cherry trees over nine trees randomly chosen among symptomatic trees in the three orchards. Colonies (20) were isolated and all appeared fluffy on potato dextrose agar and did not grow at 35°C. The morphological characteristics fit the descriptions of Phytophthora cryptogea Pethybr. & Lafferty (1). Sequence analysis of the internal transcribed spacers region of isolates shared 100% homology with P. cryptogea (GenBank Accession Nos. EF418948.1, EF418943.1, and EF153671.1). Pathogenicity of two P. cryptogea isolates (AN1 and AN2, Accession Nos. EF661576 and EF661577, respectively) was tested by soil infestation in a growth chamber at 22°C using 15 1-year-old rooted seedlings of wild rootstock of Prunus avium for each isolate. Noninoculated seedlings (15) were used as negative controls. The inoculum was produced by growing isolates on autoclaved millet grains moistened with V8 juice for 4 weeks. Each plant was inoculated with 30 cm3 of inoculum per liter of soil. Each seedling was randomly assigned to isolates AN1, AN2, or the noninoculated control and arranged in a complete random design. All plants were flooded for 24 h every 2 weeks for 8 weeks. At the end of the experiment, all inoculated seedlings showed crown wilting and root rot. Control plants showed no symptoms. Percentage of necrotic lateral roots expressed as dry weight (±SE) was 19.9 ± 0.6, 17.5 ± 0.2, and 4.4 ± 0.5, respectively, for seedlings inoculated with isolates AN1, AN2, and controls (analysis of variance F = 7.48, P < 0.01). Values of inoculated seedlings were significantly different from the control plants with the Tukey Post-Hoc test. No difference in virulence was observed between the two isolates. P. cryptogea was always reisolated from the roots of inoculated plants. Although pathogenicity of P. cryptogea on sweet cherry has been reported in the United States and other European countries (3,4), to our knowledge, this is the first record of P. cryptogea on sweet cherry orchards in Italy. The presence of P. cryptogea in cherry orchards is of significant concern because of its aggressiveness to this host and woody hosts such as apple, apricot, peach, walnut, and kiwi. References: (1) D. C Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (2) A. J. Ferguson and S. N. Jeffers. Plant Dis. 83:1129, 1999. (3) T. Tomidis and T. Sotiropoulos. N. Z. J. Crop Hortic. Sci. 31:355, 2003. (4) W. F. Wilcox and S. M. Mircetich. Phytopathology 75:1451, 1985.

15.
Ann Rheum Dis ; 66(4): 511-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16984940

RESUMO

BACKGROUND: Antibodies directed against citrullinated proteins (eg anti-cyclic citrullinated peptide (CCP)) have excellent diagnostic and good prognostic potential for rheumatoid arthritis. Type 1 autoimmune hepatitis (AIH-1) is a chronic liver disease characterised by a variety of serum autoantibodies. Recently, in a large group of patients with AIH-1 without clear rheumatoid arthritis overlap, a relatively high percentage (9%) of anti-CCP2 positivity was scored. OBJECTIVES: To characterise the citrulline-dependence of the observed anti-CCP2 positivity in AIH-1 sera as well as in other groups of patients without rheumatoid arthritis (mainly rheumatic diseases). METHODS: Serum samples of 57 patients with AIH-1 and 66 patients without rheumatoid arthritis, most of them reported as anti-CCP positive, were tested for citrulline-specific reactivity with a second generation anti-CCP kit, with the citrullinated and the corresponding non-citrullinated (arginine-containing) antigen. A subset of AIH-1 sera was also tested with a CCP1 ELISA (and arginine control). RESULTS: The anti-CCP2 reactivity of most non-rheumatoid arthritis rheumatic diseases samples (87-93%) was citrulline-specific, whereas a relatively high percentage of AIH-1 samples (42-50%) turned out to be reactive in a citrulline-independent manner. The use of citrullinated and non-citrullinated CCP1 peptides confirmed a high occurrence of citrulline-independent reactivity in AIH-1 samples. CONCLUSIONS: In rheumatoid arthritis and most non-rheumatoid arthritis rheumatologic disease sera, anti-CCP positivity is citrulline-dependent. However in some patients, particularly patients with AIH-1, citrulline-independent reactivity in the anti-CCP2 test can occur. A positive CCP test in a non-rheumatic disease (eg liver disease) should therefore be interpreted with care, and preferably followed by a control ELISA with a non-citrullinated antigen.


Assuntos
Artrite/imunologia , Autoanticorpos/sangue , Citrulina/imunologia , Hepatite Autoimune/imunologia , Peptídeos Cíclicos/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite/diagnóstico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/imunologia , Autoantígenos/imunologia , Biomarcadores/sangue , Criança , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Kit de Reagentes para Diagnóstico , Doenças Reumáticas/imunologia
16.
Lett Appl Microbiol ; 43(1): 33-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16834718

RESUMO

AIMS: To develop a quantitative real-time PCR (Rt PCR) assay for the early detection of Biscogniauxia nummularia, a xylariaceous fungus that causes strip-canker and wood decay on European beech (Fagus sylvatica L.). METHODS AND RESULTS: The molecular assay was based on TaqMan chemistry using species-specific primers and a fluorogenic probe designed on the ITS1 sequence of rRNA gene clusters. The specificity of the oligonucleotides and the probe were tested using the DNA of B. nummularia isolates from different geographic areas, of phylogenetically related species, and of some fungi commonly colonizing European beech bark and wood. A total of 31 symptomless and symptomatic shoots of European beech were collected from three forest sites in the Apennine Mountains of Italy. The percentage of positive detections of B. nummularia with the TaqMan assay was 78.6%, compared with only 14.3% of positive isolations on growth media for two sites. CONCLUSIONS: In shoots, the quantitative Rt PCR assay detected down to 8.0-fg fungal DNA per microgram of total DNA extracted. SIGNIFICANCE AND IMPACT OF THE STUDY: The assay developed in quantitative Rt PCR, by using TaqMan chemistry, revealed a rapid and sensitive method useful for the early detection of B. nummularia in symptomless European beech twigs.


Assuntos
Fagus/microbiologia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase/métodos , Árvores/microbiologia , Xylariales/isolamento & purificação , Primers do DNA , DNA Fúngico/análise , DNA Fúngico/isolamento & purificação , Taq Polimerase , Xylariales/genética
17.
Aliment Pharmacol Ther ; 22(10): 951-5, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16268969

RESUMO

BACKGROUND: Besides the autoantibodies included in the diagnostic criteria of type 1 autoimmune hepatitis, many other autoantibodies have been described in this condition. Recently, antibodies against cyclic citrullinated peptide have been validated as specific diagnostic and prognostic markers of rheumatoid arthritis. AIM: To assess whether these antibodies are part of the autoantibody repertoire of type 1 autoimmune hepatitis and correlate with rheumatological manifestations. METHODS: Antibodies against cyclic citrullinated peptide were tested by a commercially available enzyme-linked immunosorbent assay. RESULTS: The antibodies were found in 12 of 133 (9%) type 1 autoimmune hepatitis, two of 49 (4%) with primary biliary cirrhosis, one of 80 (1%) with hepatitis C virus-related chronic liver disease and 53 of 89 (60%) with rheumatoid arthritis serum samples. High titres were found only in rheumatoid arthritis and type 1 autoimmune hepatitis. No clinical (in particular rheumatological manifestations), biochemical or immunoserological differences were detectable between antibodies against cyclic citrullinated peptide positive and negative type 1 autoimmune hepatitis sera, with the exception of rheumatoid factor, always negative in the positive ones. CONCLUSIONS: Antibodies against cyclic citrullinated peptide can be detected in a subgroup of patients with type 1 autoimmune hepatitis. They might be part of the wide range of autoantibody production characteristic of this condition and/or, less probably, be predictive of future rheumatoid arthritis development.


Assuntos
Autoanticorpos/sangue , Doenças Autoimunes/imunologia , Anticorpos Anti-Hepatite/sangue , Hepatite/imunologia , Peptídeos Cíclicos/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
Plant Dis ; 87(3): 315, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30812774

RESUMO

English (Persian) walnut (Juglans regia), among the most widely cultivated species of Juglans worldwide, is cultivated primarily for fruit production but also for timber. In the last 10 years, walnut decline causing leaf yellowing, sparse foliage, overall decline, and plant death has increased in Italian commercial orchards. In Italy, Phytophthora cactorum, P. cambivora, P. cinnamomi, and P. cryptogea are associated with this disease (1,4). Over the last 5 years, P. cinnamomi was the most widely isolated and destructive species (1). Recently, a different species of Phytophthora was isolated from diseased roots and soil from around lateral roots of 10 declining trees in two orchards in the Veneto Region of northern Italy. Another species of Phytophthora was isolated consistently from rotted roots of declining walnut trees in two orchards in the Campania Region of southern Italy. Phytophthora spp. were isolated directly from plant material or Rhododendron spp. leaf baiting on soil samples with PARBhy selective medium (10 mg of pimaricin, 250 mg of ampicillin [sodium salt], 10 mg of rifampicin, 50 mg of hymexazol, 15 mg of benomyl, 15 g of malt extract, 20 g of agar in 1,000 ml of H2O). Two species of Phytophthora were identified based on morphological and cultural characteristics (2). The species from trees in the Veneto Region was identified as P. nicotianae. All isolates produced papillate, spherical to obturbinate, occasionally caducous sporangia with short pedicels, terminal and intercalary chlamydospores, and were mating type A2. The species isolated from trees in the Campania Region was identified as P.citricola. Isolates were homothallic, produced semipapillate, persistent, obclavate to obpyriform sporangia, occasionally with two apices, and antheridia paragynous. Identifications were confirmed by comparing restriction fragment length polymorphism patterns of the internal transcribed spacer region of rDNA with those obtained from previously identified species of Phytophthora. Pathogenicity of two isolates each of P. citricola and P. nicotianae was tested on 2-year-old potted walnut seedlings. Inocula were prepared by inoculating sterilized millet seeds moistened with V8 broth with plugs of mycelium and incubated for 4 weeks at 20°C in the dark. Infested seeds were added to potting soil at a rate of 3% (wt/vol). One day later, pots were flooded for 48 h to promote sporulation. Ten noninoculated seedlings were used as the control. Symptoms were assessed 2 months after inoculation. Seedlings inoculated with P. nicotianae developed necrosis of feeder and lateral roots, but only limited infection of taproots. Seedlings inoculated with P. citricola developed necroses at the insertion points of lateral roots. All four isolates produced visible damage to lateral roots on inoculated plants. P. nicotianae and P. citricola were reisolated from respectively infected roots. Results from these inoculations confirmed P. nicotianae and P. citricola as root pathogens of English walnut. Both species were associated with walnut decline as reported in the United States (3). To our knowledge, this is the first report of P. nicotianae and P. citricola on J. regia in Europe. References: (1) A. Belisario et al. Petria 11:149. (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (3) M. E. Matheron and S. M. Mircetich. Phytopathology 75:977, 1985. (4) A. M. Vettraino et al. Plant Dis. 86:328, 2002.

19.
Plant Dis ; 86(3): 328, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30818623

RESUMO

English (Persian) walnut (Juglans regia L.) is among the most widely cultivated species in pure and mixed plantations of broadleaved trees in Italy. A decline of walnut of increasing occurrence has been reported recently in new plantations in central and northern Italy. Symptoms of the decline were typically characterized by yellowing of the foliage, defoliation, and plant death. Dark, flame-shaped necroses were often present at the collar. Phytophthora cactorum, P. cambivora, and P. cinnamomi were among the species associated with necrotic tissues of the collar and main roots (1). Furthermore, a Phytophthora sp. was isolated from soil removed from the lateral root zone of 6 of 15 declining trees in 3 walnut plantations, 2 in northern Italy and 1 in central Italy. Isolations were made by baiting with Rhododendron leaves and plating on PARBhy selective medium (3). The species isolated was identified as P. cryptogea on the basis of morphological and cultural characteristics (2). All isolates produced oval to obpyriform, nonpapillate sporangia and were mating type A2. Identification of the isolates was confirmed by comparing the restriction fragment length polymorphism patterns of the internal transcribed spacer region of ribosomal DNA with those obtained from previously identified Phytophthora species. Pathogenicity tests on potted 2-year-old walnut seedlings were conducted using two isolates of P. cryptogea. Inoculum was prepared by growing isolates on sterilized millet seeds added to soil at 2.5% (wt/vol). Sporulation was induced by 24-h flooding of the soil. Symptoms were assessed 1 month after inoculation. Ten uninoculated seedlings were used as controls. Inoculated seedlings showed no symptoms on the tap root, but there were extensive necroses of lateral roots ranging from 14 to 75% (average 38.6 ± 6.7 SE) of total lateral root (dry weight) compared with values of 0 to 11% (average 3 ± 1.5 SE) for uninoculated seedlings. P. cryptogea was easily reisolated from infected lateral roots and from the soil of inoculated pots. The inoculation trials confirmed P. cryptogea as a feeder-root pathogen of walnut in Italy. To our knowledge, this is the first report of P. cryptogea on English walnut in Italy. This species often has been associated with walnut decline in the United States (2) and on other woody plants in Italy (3). References: (1) A. Belisario et al. Petria 11:127, 2001. (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Association, St. Paul, MN, 1996. (3) A. M. Vettraino et al. Plant Pathol. 50:90, 2001.

20.
Eur J Biochem ; 268(23): 6214-20, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11733017

RESUMO

Haem binding to human serum albumin (HSA) endows the protein with peculiar spectroscopic properties. Here, the effect of ibuprofen and warfarin on the spectroscopic properties of ferric haem-human serum albumin (ferric HSA-haem) and of ferrous nitrosylated haem-human serum albumin (ferrous HSA-haem-NO) is reported. Ferric HSA-haem is hexa-coordinated, the haem-iron atom being bonded to His105 and Tyr148. Upon drug binding to the warfarin primary site, the displacement of water molecules--buried in close proximity to the haem binding pocket--induces perturbation of the electronic absorbance properties of the chromophore without affecting the coordination number or the spin state of the haem-iron, and the quenching of the 1H-NMR relaxivity. Values of Kd for ibuprofen and warfarin binding to the warfarin primary site of ferric HSA-haem, corresponding to the ibuprofen secondary cleft, are 5.4 +/- 1.1 x 10(-4) m and 2.1 +/- 0.4 x 10(-5) m, respectively. The affinity of ibuprofen and warfarin for the warfarin primary cleft of ferric HSA-haem is lower than that reported for drug binding to haem-free HSA. Accordingly, the Kd value for haem binding to HSA increases from 1.3 +/- 0.2 x 10(-8) m in the absence of drugs to 1.5 +/- 0.2 x 10(-7) m in the presence of ibuprofen and warfarin. Ferrous HSA-haem-NO is a five-coordinated haem-iron system. Drug binding to the warfarin primary site of ferrous HSA-haem-NO induces the transition towards the six-coordinated haem-iron species, the haem-iron atom being bonded to His105. Remarkably, the ibuprofen primary cleft appears to be functionally and spectroscopically uncoupled from the haem site of HSA. Present results represent a clear-cut evidence for the drug-induced shift of allosteric equilibrium(a) of HSA.


Assuntos
Heme/química , Ibuprofeno/farmacologia , Albumina Sérica/química , Albumina Sérica/efeitos dos fármacos , Varfarina/farmacologia , Sítio Alostérico , Sítios de Ligação , Espectroscopia de Ressonância de Spin Eletrônica , Heme/metabolismo , Humanos , Ibuprofeno/metabolismo , Técnicas In Vitro , Cinética , Substâncias Macromoleculares , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Albumina Sérica/metabolismo , Espectrofotometria , Varfarina/metabolismo
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