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1.
Ann Med Surg (Lond) ; 69: 102662, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34429947

RESUMO

INTRODUCTION: Traumatic peroneal nerve injury (PNI) caused by ski or snowboard edges is a severe but scarcely reported accident. METHODS: In a 20-year retrospective study, all skiers and snowboarders with this injury treated surgically at the Department of Plastic, Reconstructive and Aesthetic Surgery at the Medical University of Innsbruck, Austria, were included, covering a period from 1999/2000 to 2018/2019. RESULTS: In total, 34 patients were included in this study (30 males (88.2%) and 4 (11.8%) females). Of these 34 injured skiers or snowboarders, 33 (97.1%) were recreational athletes and Non-Austrian citizens, and 21 (61.8%) patients sustained accidental injuries without collision. All of the injuries under investigation, i.e., open lacerations, most often with complete transection, were the patients' main injuries. Surgery was performed with direct coaptation in 24 patients (70.6%), and with a suralis nerve graft in the other 10 patients (29.4%). CONCLUSION: Traumatic laceration of the peroneal nerve at the knee level by sharp ski or snowboard edges is a rare but severe injury. Causes for this injury may be multifactorial. Recommendations to reduce the risk of such an injury may follow general instructions and warnings to skiers and snowboarders regarding equipment, familiarity with the region, as well as appropriate skills and training.

2.
Sci Rep ; 8(1): 2760, 2018 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-29426889

RESUMO

Engineered silica nanoparticles (NPs) have attracted increasing interest in several applications, and particularly in the field of nanomedicine, thanks to the high biocompatibility of this material. For their optimal and controlled use, the understanding of the mechanisms elicited by their interaction with the biological target is a prerequisite, especially when dealing with cells particularly vulnerable to environmental stimuli like neurons. Here we have combined different electrophysiological approaches (both at the single cell and at the population level) with a genomic screening in order to analyze, in GT1-7 neuroendocrine cells, the impact of SiO2 NPs (50 ± 3 nm in diameter) on electrical activity and gene expression, providing a detailed analysis of the impact of a nanoparticle on neuronal excitability. We find that 20 µg mL-1 NPs induce depolarization of the membrane potential, with a modulation of the firing of action potentials. Recordings of electrical activity with multielectrode arrays provide further evidence that the NPs evoke a temporary increase in firing frequency, without affecting the functional behavior on a time scale of hours. Finally, NPs incubation up to 24 hours does not induce any change in gene expression.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Nanopartículas , Células Neuroendócrinas/efeitos dos fármacos , Neurônios/metabolismo , Dióxido de Silício/farmacologia , Animais , Linhagem Celular , Expressão Gênica/efeitos dos fármacos , Hipotálamo/citologia , Camundongos , Células Neuroendócrinas/fisiologia , Neurônios/efeitos dos fármacos
3.
Sci Rep ; 6: 28889, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27363302

RESUMO

The fate of human adipose tissue stem cells (ASCs) is largely determined by biochemical and mechanical cues from the extracellular matrix (ECM), which are sensed and transmitted by integrins. It is well known that specific ECM constituents influence ASC proliferation and differentiation. Nevertheless, knowledge on how individual integrins regulate distinct processes is still limited. We performed gene profiling of 18 alpha integrins in sorted ASCs and adipocytes, identifying downregulations of RGD-motif binding integrins integrin-alpha-V (ITGAV) and integrin-alpha-5 (ITGA5), upregulation of laminin binding and leukocyte-specific integrins and individual regulations of collagen and LDV-receptors in differentiated adipocytes in-vivo. Gene function analyses in in-vitro cultured ASCs unraveled differential functions of ITGA5 and ITGAV. Knockdown of ITGAV, but not ITGA5 reduced proliferation, caused p21(Cip1) induction, repression of survivin and specific regulation of Hippo pathway mediator TAZ. Gene knockdown of both integrins promoted adipogenic differentiation, while transgenic expression impaired adipogenesis. Inhibition of ITGAV using cilengitide resulted in a similar phenotype, mimicking loss of pan-ITGAV expression using RNAi. Herein we show ASC specific integrin expression patterns and demonstrate distinct regulating roles of both integrins in human ASCs and adipocyte physiology suggesting a negative impact of RDG-motif signaling on adipogenic differentiation of ASCs via ITGA5 and ITGAV.


Assuntos
Diferenciação Celular/genética , Proliferação de Células/genética , Integrina alfa5/genética , Integrina alfaV/genética , Células-Tronco/metabolismo , Adipócitos/metabolismo , Adipogenia/genética , Tecido Adiposo/citologia , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Integrina alfa5/metabolismo , Integrina alfaV/metabolismo , Interferência de RNA
4.
J Wound Care ; 23(11): 590, 592-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25375407

RESUMO

Effective wound bed preparation is an essential element in the healing of chronic wounds, including pressure ulcers (PUs). Negative pressure wound therapy (NPWT) reduces oedema, stimulates the formation of granulation tissue and helps remove wound exudate. This helps prepare the wound bed for secondary healing, skin grafting or coverage with flaps. Combining NPWT with an instillation phase using an antiseptic (octenidine based) irrigation solution is a novel approach to PU management. Three patients with Category 4 gluteal PUs were treated with NPWT and instillation fluid, following surgical debridement of necrotic tissue. The aim was to achieve optimal wound bed preparation prior to wound closure by local fasciocutaneous flap. The antiseptic efficacy of octenilin wound irrigation solution in microorganism eradication was quantified by in vitro tests simulating real conditions using leg ulcer vacuum exudates. All wounds completely healed after four weeks, and no adverse incidents occurred due to instillation of octenidine. No recurrence of the PU occurred during a one year follow-up.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Nádegas/lesões , Tratamento de Ferimentos com Pressão Negativa , Úlcera por Pressão/terapia , Piridinas/uso terapêutico , Infecção dos Ferimentos/tratamento farmacológico , Humanos , Iminas , Masculino , Irrigação Terapêutica , Resultado do Tratamento , Cicatrização
6.
G Chir ; 33(10): 343-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23095565

RESUMO

Pathogenesis, classification and treatment of non-parasitic splenic cysts (NPSCs) are controversial. The utility of percutaneous aspiration of the cyst is not well understood. We report a case of a 32 year-old woman with a symptomatic giant epidermoid cyst of the spleen treated with laparoscopic splenectomy. A percutaneous transcatheter drainage was performed under ultrasound guidance before surgical procedure in order to classify the type of cyst and to choose the best treatment.


Assuntos
Cistos/cirurgia , Drenagem/métodos , Esplenopatias/cirurgia , Adulto , Feminino , Humanos
9.
Neurol Sci ; 30 Suppl 1: S113-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19415439

RESUMO

Cutaneous allodynia is a frequent complain in headache patients, particularly in those with migraine. A stronger association is present in patients with migraine with aura and with chronic or transformed migraine. The aim of the present study was to investigate if the psychological profile may be related to the presence/absence of allodynia in a sample of headache patients. The psychological profile of patients was assessed by the SCL90R; the presence of allodynia was assessed by a set of semi-structured questions used in previous studies. For the purpose of the study, patients were divided into subgroups according to the headache type (ICDH-II diagnoses), as well as to the temporal pattern (episodic or chronic). A total of 213 consecutive headache patients were studied. Most patients had episodic migraine (116); 37 had tension-type headache. Overall, 156 patients had episodic headache forms, and 57 had chronic forms. As far as allodynia, 93 were non-allodynic; 120 presented allodynic symptoms during their headaches. No significant difference was found between allodynic and non-allodynic patients neither if studied in a whole group (t test, P = 0.10 NS) nor when patients were evaluated comparing different subgroups on the basis of headache type, and of the episodic/chronic pattern. Our results suggest that the presence/absence of allodynia may not be influenced by the psychological profile.


Assuntos
Cefaleia/psicologia , Dor/psicologia , Doença Crônica/psicologia , Feminino , Cefaleia/epidemiologia , Humanos , Masculino , Transtornos de Enxaqueca/epidemiologia , Transtornos de Enxaqueca/psicologia , Dor/epidemiologia , Determinação da Personalidade , Inquéritos e Questionários , Cefaleia do Tipo Tensional/epidemiologia , Cefaleia do Tipo Tensional/psicologia
11.
Neurol Sci ; 27(5): 328-31, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17122942

RESUMO

The aim of this report is to quantify the amount of spontaneous microembolism detected in brain vessels by transcranial Doppler (TCD) during transcatheter closure of right-to-left shunt (RLS). We examined 29 patients who had had a stroke or a transient ischaemic attack (17 females and 12 males; mean age 45+/-15 years). They all underwent TCD monitoring during the procedure and microembolic signals (MES) were recorded. Detection of MES was distributed as follows: during femoral catheterisation in 8 patients (25%), during atrial catheterisation in 5 patients (17%), during transeptal crossing in 14 patients (48%), during left disc opening in 28 patients (96%) and during right disc opening in 7 patients (24%). The highest rates of MES were observed during left disc opening and less during transeptal crossing with an average count of 31 (range 3-135) and 3 (range 1-18) respectively. Brain embolism occurs throughout the procedure after femoral catheterisation for PFO closure. Our results indicate that the majority of MES reached the brain during the opening of the left disc in the left atrium: 28/29 patients exhibited MES with an average of 31 (3-135), thus supporting the notion that gas embolism accounted for the findings.


Assuntos
Cateterismo Cardíaco/efeitos adversos , Comunicação Interatrial/cirurgia , Complicações Intraoperatórias , Ultrassonografia Doppler Transcraniana , Adulto , Cateterismo Cardíaco/métodos , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/cirurgia , Feminino , Comunicação Interatrial/diagnóstico por imagem , Humanos , Embolia Intracraniana/diagnóstico por imagem , Embolia Intracraniana/etiologia , Embolia Intracraniana/cirurgia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Pediatr Cardiol ; 26(3): 231-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15977084

RESUMO

The aim of this preliminary case-control study was to compare, in patients with migraine and PFO, transcatheter closure of PFO vs. medical treatments. Twelve patients were treated with antimigraine drugs and twelve underwent percutaneous transcatheter closure. All patients were followed-up for 12 months. Our preliminary results seem to confirm that, compared to medical treatment, PFO closure is by far more effective in reducing both frequency, duration and intensity of migraine attacks. Furthermore, the occurrence of prodromal aura is almost abolished.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Cateterismo Cardíaco , Comunicação Interatrial/terapia , Transtornos de Enxaqueca/terapia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
15.
Plant Dis ; 89(6): 684, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30795404

RESUMO

The Asian soybean rust caused by the fungus Phakopsora pachyrhizi was cited for the first time in Argentina during the 2002-2003 growing season (3). During 2003-2004, the disease spread to other northern provinces and was also observed in north-central Santa Fe, the main producing soybean province of the country. Because the disease appeared at the end of the crop growing season (late March to early April) it had little or no impact on crop yields. The objectives of this study were to characterize morphologically and pathometrically the disease on soybean and check the presence of P. pachyrhizi on volunteer soybean plants that could eventually carry the disease to the next growing season. The study was conducted in the San Justo Department, Santa Fe Province (between 30 and 31°S latitude), where the presence of the soybean rust was molecularly confirmed by Sistema Nacional Vigilancia y Monitoreo (on-line publication at www.sinavimo.gov.ar ). Three field locations were sampled and identified as M1, M2, and M3. Transversal cuts of soybean leaves through rust lesions and histo-pathological staining were used for micromor-phologic characterization of the developmental stages of P. pachyrhizi. The disease incidence was estimated as the proportion of affected soybean plants and leaves. Average severity, expressed as the percentage of leaf area affected, including chlorosis, was measured on the terminal leaflet of leaves sampled from the lower one-third of the canopy. Three replicates of 10 plants, randomly chosen, were used. The number of uredinia per square centimeter and per lesion (symptomatic foliar area showing chlorosis and necrosis caused by the fungus) was measured on the undersides of the sampled leaflets at ×40 magnification (1). Typical signs and symptoms of P. pachyrhizi coexisted on soybean leaves with brown spot (Septoria glycines), downy mildew (Peronospora manshurica), anthracnose (Colletotrichum truncatum), and blight and leaf spot (Cercospora kikuchii) and also with bacteria (Pseudomonas and Xanthomonas spp.). Uredinia and telia of the P. pachyrhizi cycle were observed. Uredinia were also observed on soybean petioles. The average size of urediniospores (n = 60) was 23.3 × 16.6 µm. Telia were located adjacent to the uredinia. These telia were dark and crusty with four stacked layers of teliospores. Rust incidence in plants was 100% for the three fields, while the incidence in leaves was 100% for M1 and M2 and 60% for M3. Average disease severity was 50.3, 25.6, and 14.8% for M1, M2, and M3, respectively. The mean number of uredinia per square centimeter was 327, 179, and 177, for M1, M2, and M3, respectively. The number of uredinia per lesion ranged from 1 to 6. P. pachyrhizi was also found on volunteer soybean plants that emerged shortly after harvest. On 40 leaflets, the foliar incidence was 25%, showing one to two lesions with one to two uredinios per leaflet (2). The volunteer soybean plants could constitute a potential early source of inoculum. References: (1) M. Marcchetti et al. Phytopathology. 66:461, 1976. (2) R. Pioli et al. La roya asiática en Santa. Fe, Arg. XII Cong. AAPRESID, II Sem. Internac. Soja, Arg. 283-290, 2004. (3) R. L. Rossi. Plant Dis. 87:102, 2003.

16.
Stroke ; 35(9): 2140-4, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15284445

RESUMO

BACKGROUND AND PURPOSE: Transcatheter closure of patent foramen ovale (PFO) is increasingly being performed and monitored with transthoracic or transesophageal echocardiography, whereas contrast-enhanced transcranial Doppler (ce-TCD), which probably represents the most suitable tool to quantify right-to-left shunt (RLS) in the brain vessels, has been systematically overlooked. Our goal is to prospectively assess efficacy and safety of PFO transcatheter closure using ce-TCD. METHODS: A total of 140 consecutive patients (mean age, 46+/-13 years; male/female ratio, 63/77) with PFO-related large RLS and no other recognized cause of focal cerebral ischemia underwent transcatheter closure. TCD was done preoperatively and 1 month after the procedure in all patients, after 3 months in 120, after 6 months in 112, and after 1 year in 104 patients. RESULTS: Implantation was successful in all patients. During Valsalva strain, a large shunt was still detectable in 31 of 140 (22%), 15 of 120 (13%), 9 of 112 (8%), and 9 of 104 (9%) patients at the 1-, 3-, 6-, and 12-month visits, respectively. Periprocedural and postprocedural complications included atrial fibrillation in 8% and scintillating scotomata in 6% of patients. During the 1-year follow-up period, only 1 transient ischemic attack was recorded in a patient with paroxysmal atrial fibrillation and complete PFO closure. CONCLUSIONS: Transcatheter PFO closure in patients with cryptogenic stroke and large RLS may be less successful than reported previously. TCD appears the ideal tool to follow up the closure process and to identify early, during follow-up, those patients who will be left with a significant shunt. Atrial fibrillation is more common than believed previously and may underlie the occurrence of further cerebrovascular events despite complete PFO closure. Irritative visual phenomena may occur as a consequence of nickel toxicity.


Assuntos
Cateterismo Cardíaco , Comunicação Interatrial/cirurgia , Próteses e Implantes , Adulto , Fibrilação Atrial/etiologia , Feminino , Seguimentos , Comunicação Interatrial/complicações , Comunicação Interatrial/diagnóstico , Humanos , Embolia Intracraniana/etiologia , Embolia Intracraniana/prevenção & controle , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Níquel/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Estudos Prospectivos , Escotoma/etiologia , Tomografia Computadorizada por Raios X , Falha de Tratamento , Resultado do Tratamento , Ultrassonografia Doppler Transcraniana , Manobra de Valsalva
17.
Plant Dis ; 88(2): 220, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30812432

RESUMO

Fusarium graminearum, a pathogen of wheat and corn, was reported recently as a saprophytic fungus colonizing soybean (Glycine max L. Merr.) fruits and seeds at R7 in Argentina (2). To evaluate the capacity of F. graminearum obtained from stem and seeds of symptomatic soybean plants that cause disease on soybean seedlings, isolates were obtained during the 2001 to 2002 growing season from: (i) the basal one-third of stems from field-grown soybean plants, collected at R5, with light brown external and internal discoloration and leaves with interveinal chlorosis; and (ii) soybean seeds with pink tegument. The pathogen was isolated on potato glucose agar acidified with 0.2% lactic acid (PGAA). Isolates were identified as F. graminearum on the basis of growth rate and pigmentation of colonies on PGAA, lack of microconidia (1), and morphology and size of typical macroconidia in sporodochia developed on Spezieller Nährstoffarmer Agar (3). Isolates of F. graminearum, CE135 and CE136 (from wheat) and CE137 (from corn) deposited in the Centro de Referencia en Micología (CEREMIC), Fac. Farmacia y Bioquímica, UNR, Argentina, were used as references in identifying the soybean isolates. Plants (14-day-old) were inoculated separately with stem and seed isolates in the greenhouse at 26 ± 2 and 20 ± 2°C day/night temperature by inserting a piece of mycelium into a wound made with a scalpel in the hypocotyl. A completely randomized block design (RCB) was utilized with four replicate pots with four plants per pot. Plants wounded but without mycelium served as controls. This test was conducted twice (experiments 1 and 2). Another test was completed by burying a thin layer of wheat caryopsis colonized by fungal mycelium of the stem isolate CE170 in the soil of pots. Plants in pots with soil without inoculum served as controls (4). The experiment was conducted twice (experiments 3 and 4) in an RCB with five replications, four plants per replication. The progress of symptoms in experiments 1 and 2 were stem with light brown discoloration around the inoculation point that extended progressively along the stem, interveinal chlorosis or loss of turgence of unifoliate leaves, and interveinal chlorosis of trifoliate leaves followed by plant wilting and death. Twenty-one days after inoculation, average percentages of dead plants (%DP) was 42 and 21% for stem and seed isolates, respectively. For experiments 3 and 4, %DP was 56%, 45 days after emergence. These plants had roots with light brown, necrotic areas. Control plants remained healthy. The pathogen was reisolated from the stem (100%) and root (57%) tissues of symptomatic plants but not from similar tissues of control plants. To our knowledge, this is the first report of a pathogenic relationship between F. graminearum and soybean. References: (1) P. E. Nelson et al. Fusarium species: An Illustrated Manual for Identification. The Pennsylvania State University Press, University Park, PA, 1983. (2) R.N. Pioli et al. Fitopatología 35(2):111, 2000. (3) B. A. Summerell et al. Plant Dis. 87:117, 2003. (4) C. E. Windels. Fusarium. Pages 115-128 in: Methods for Research on Soilborne Phytopathogenic Fungi. L. L. Singleton, J. D. Mihail, and C. M. Rush, eds. The American Phytopathological Society, St. Paul, MN, 1992.

18.
Eur J Neurol ; 10(2): 129-35, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12603287

RESUMO

The importance of patent foramen ovale (PFO) in stroke of unknown cause remains disputed, as PFO may be present in up to 20% of normal people and in a high proportion of patients with non-vascular disorders. Recent evidence suggests that the amount of right-to-left shunt (RLS) may be the crucial factor for stroke occurrence and relapse. The aim of the study was to assess predictors of recurrence in PFO-related stroke patients with particular emphasis on amount of shunting. Patients less than 61 years old who had been admitted for a PFO-related stroke within the previous 5 years, were re-evaluated on a follow-up visit. The clinical syndrome, residual disability, vascular risk factors and number of relapses as the index event were assessed. RLS sizing was semi-quantitatively performed with saline-enhanced transcranial Doppler (TCD), by assuming a cut-off of more or less 10 bubbles recorded in the cerebral vessels as a criterion to discriminate large versus small shunt, respectively. Thereafter patients were prospectively followed-up for a median time of 23 months. Total follow-up was 61 months. Fifty-nine patients (M/F = 23/36, mean age 43 +/- 13) were studied. Overall there were 23 relapses in 13 patients. The amount of shunting was the only significant independent variable associated with relapse: at the end of the follow-up period the recurrence rate was 0.66 and 8.2% per patient per year in patients with small and large shunt, respectively. This difference was statistically significant (chi2 = 10.39, P = 0.0012; OR 17.05, 95% CI 2.10-755.22). In patients with PFO-related stroke, the amount of RLS as assessed with TCD is the only independent predictor of relapse. PFO sizing is mandatory in patients with PFO.


Assuntos
Comunicação Interatrial/complicações , Acidente Vascular Cerebral/complicações , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Ultrassonografia Doppler Transcraniana
19.
Surg Endosc ; 16(5): 814-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11997829

RESUMO

BACKGROUND: The use of the ultrasonically activated scalpel (UAS) for vessel closure has attained widespread acceptance in many surgical fields. The aim of our study was to investigate the electron microscopic changes to the blood vessels after the application of UAS. METHODS: We collected 10 arterial and 10 venous segments from vessels that had previously been closed by UAS during abdominal operations. The samples were then prepared for ultramicroscopic analysis. Pathological changes in the lumen and the three wall layers of the blood vessel were examined under scanning and transmission electron microscopy. RESULTS: All of the vessel segments showed similar changes: the presence of a blood clot, endothelial cell condensation, coagulative necrosis of the wall, and charring of the vessel at its tip. The edge of the cut vessel were closed by the coagulation bond, which was tied up by collagen fibrils escaped from denaturation. CONCLUSION: When ultrasonic energy is applied to tissues, it changes their structure so as to make a new extracellular matrix.


Assuntos
Eletrocoagulação/métodos , Terapia por Ultrassom/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Ducto Cístico/irrigação sanguínea , Ducto Cístico/diagnóstico por imagem , Ducto Cístico/cirurgia , Ducto Cístico/ultraestrutura , Hemorroidas/diagnóstico por imagem , Hemorroidas/patologia , Hemorroidas/cirurgia , Humanos , Microscopia Eletrônica/métodos , Microscopia Eletrônica de Varredura/métodos , Necrose , Omento/irrigação sanguínea , Omento/diagnóstico por imagem , Omento/ultraestrutura , Estômago/irrigação sanguínea , Estômago/diagnóstico por imagem , Estômago/ultraestrutura , Ultrassonografia
20.
Plant Dis ; 86(12): 1403, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30818452

RESUMO

The first report of soybean stem canker (SSC) caused by Diaporthe phaseolorum var. caulivora in South America was published in 2001, and was based on an isolate obtained in 1999 at Oliveros, Santa Fe (32°33'S, 60°51'W), Argentina (2). During the 2001 to 2002 growing season, isolates of D. phaseolorum var. caulivora were obtained from stems of field-grown soybeans (Glycine max L.) exhibiting SSC symptoms. Isolates were collected in three localities of the main soybean-producing region of Argentina: Marcos Juárez, Córdoba (32°66'S, 62°10'W); Salto, Buenos Aires (34°20'S, 60°33'W); and Diego de Alvear, Santa Fe (34°21'S, 62°10'W), and disease incidence in the fields was 10 to 60%, 5 to 15%, and 10 to 20%, respectively. The pathogen was isolated on potato glucose agar acidified with 0.2% lactic acid cultured in the dark at 25 ± 1°C. White colonies with compact and tufted mycelium were produced and turned yellow and light tan after 6 days. Appressed and fluffy mycelia were observed in old cultures. Stromata (2 mm diameter) were produced but pycnidia were not detected. After 20 days in culture at 25 ± 1°C under a 12-h light and 12-h dark regime, clustered perithecia developed on stem segments. For each isolate, 10 perithecia, 90 asci, and 30 bicellular, biguttulate ascospores were measured. Averages of asci length and width were 28.3 ± 2.3 and 5.9 ± 0.7 µm, respectively. Averages of ascospores mean length and width were 8.4 ± 0.6 and 2.5 ± 0.4 µm, respectively. These measures were similar to the measures obtained previously (2). Based on these features, the new isolates were classified as D. phaseolorum var. caulivora (Athow & Caldwell). Clustered perithecia, smaller asci and ascospores, and the development of fluffy mycelia with age were the main characteristics that distinguished D. phaseolorum var. caulivora from D. phaseolorum var. meridionalis (1). Pathogenicity trials were performed on cvs. Tracy M, Crockett, Hutchenson, and RA 702 in the greenhouse by placing a small amount of mycelium in soybean seedling hypocotyls wounds made with a scalpel. The pathogen was reisolated from stem portions of the symptomatic plants. Control plants remained healthy. The results reported here show that D. phaseolorum var. caulivora is widely disseminated in the main soybean-producing region of Argentina, where it coexists with D. phaseolorum var. meridionalis (2). The coexistence of both varieties indicates pathogen variability in the region is higher than previously recognized. References: (1) R. N. Pioli et al. Plant Dis. 83:1071, 1999. (2) R. N. Pioli et al. Plant Dis. 85:95, 2001.

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