Atención de enfermería en la administración preoperatoria de mitomicina C mediante EMDA / No disponible

Cada vez existen más estudios que demuestran la eficacia de la instilación de mitomicina C (MMC) mediante sistema EMDA prerresección transuretral (RTU), en pacientes con tumor vesical no músculo invasivo (TVNMI), disminuyendo la recidiva de tumor y aumentando el tiempo libre de enfermedad. El sistema EMDA es una técnica sencilla de realizar y de fácil aprendizaje por el personal de enfermería. Por lo que queremos mostrar su procedimiento y cuidados propios

There is an increasing number of studies that show the efficiency of instillation of mitomycin via a pre-resection transurethral (RTU) EMDA system, in patients with non-muscle invasive bladder cancer (TVNMI), by reducing the time of recurrence and increasing disease-free survival. EMDA system is a simple technique to carry out and easy to learn, so it is essential to show its procedure and nursing care

Uroguanylin: a new actor in the energy balance movie.

Uroguanylin (UGN) is a potential target in the fight against obesity. The mature protein is released after enzymatic cleavage from its natural precursor, proUGN. UGN is mostly produced in the gut, and its production is regulated by nutritional status. However, UGN is also produced in other tissues such as the kidneys. In the past, UGN has been widely studied as a natriuretic peptide owing to its involvement in several different pathologies such as heart failure, cancer and gastrointestinal diseases. However, recent studies have suggested that UGN also acts as a regulator of body weight homeostasis because it modulates both food intake and energy expenditure. This ultimately results in a decrease in body weight. This action is mediated by the sympathetic nervous system. Future studies should be directed at the potential effects of UGN agonists in regulating body weight in human obesity.

Dynamics and universal scaling law in geometrically-controlled sessile drop evaporation.

The evaporation of a liquid drop on a solid substrate is a remarkably common phenomenon. Yet, the complexity of the underlying mechanisms has constrained previous studies to spherically symmetric configurations. Here we investigate well-defined, non-spherical evaporating drops of pure liquids and binary mixtures. We deduce a universal scaling law for the evaporation rate valid for any shape and demonstrate that more curved regions lead to preferential localized depositions in particle-laden drops. Furthermore, geometry induces well-defined flow structures within the drop that change according to the driving mechanism. In the case of binary mixtures, geometry dictates the spatial segregation of the more volatile component as it is depleted. Our results suggest that the drop geometry can be exploited to prescribe the particle deposition and evaporative dynamics of pure drops and the mixing characteristics of multicomponent drops, which may be of interest to a wide range of industrial and scientific applications.

The carotid body, a neurogenic niche in the adult peripheral nervous system.

We have described a new population of adult neural stem cells residing in the carotid body, a chemoreceptor organ in the peripheral nervous system. These progenitor cells support neurogenesis in vivo in response to physiological stimuli like hypoxemia, and give rise to multipotent neurospheres in culture. Studying the biology of CB stem cells helps to understand the physiological adaptations of the organ, and might shed light on the pathogenesis of CB tumors. Understanding proliferation and differentiation of these cells will enable their use for cell therapy against neurodegenerative diseases.

Vincristine, an efficacious alternative for diffuse neonatal haemangiomatosis.

Diffuse neonatal haemangiomatosis (DNH) is an uncommon condition characterized by multiple cutaneous and visceral haemangiomas frequently causing severe complications. Corticosteroids constitute the first therapeutic line; however, when they fail, other alternatives are available, provided possible side effects are closely monitored during and after treatment. We present a case of life-threatening DNH, non-responsive to corticosteroids, successfully treated with Vincristine with minor side effects. We conclude that Vincristine is a valid alternative in corticosteroid-resistant DNH.

Colestasis asociada a la nutrición parenteral prolongada en el período neonatal: posible eficacia del ácido ursodesoxicólico / Cholestasis associated with prolonged parenteral nutrition in neonates: The role of urso-deoxycholic acid

Introducción: La morbilidad asociada a la prematuridad hace necesaria en ocasiones la administración de una nutrición parenteral prolongada (NPP) que tiene como una de las complicaciones asociadas el desarrollo de colestasis. Material y métodos: Análisis retrospectivo de 2 años que incluyó el estudio de marcadores de daño hepatocelular e indicadores de colestasis en neonatos con NPP tratados o no con ácido ursodesoxicólico (AUDC). Resultados: De 24 pacientes estudiados, 17 recibieron AUDC y 7 fueron controles. En el grupo tratado se evidenció un descenso significativo (p<0,05) en las cifras de gammaglutamil transpeptidasa y de bilirrubina conjugada a partir de las 4 a las 5 semanas de tratamiento, respectivamente, comparado con el grupo no tratado. Asimismo, se constató una correlación significativa (p<0,01) entre las cifras de bilirrubina conjugada máxima y el tiempo de nutrición parenteral total. Conclusiones: Los pacientes que recibieron AUDC experimentaron un descenso más rápido de los marcadores bioquímicos de colestasis, pero no de los de citotoxicidad en la enfermedad hepatobiliar asociada a NPP. Sin embargo, el presente estudio tiene limitaciones derivadas de su diseño retrospectivo y, por tanto, sería deseable realizar un estudio aleatorizado con potencia estadística adecuada para evaluar la utilidad tanto profiláctica como terapéutica del AUDC en las complicaciones hepáticas de la NPP (AU)

Introduction: The morbidity associated with prematurity occasionally leads to the use of prolonged parenteral nutrition, with the subsequent development of cholestasis being one of its complications. Patients and methods: This is a two year retrospective study which compared biochemical markers of liver damage and cholestasis in premature babies who received or did not receive urso-deoxycholic acid for parenteral nutrition associated cholestasis. Results: Of a total of 24 recruited patients 17 received urso-deoxycholic acid and 7 did not. In the treated group significant decreases (P<0.05) in gamma-glutamyltranspeptidase and conjugated bilirubin were found after four and five weeks of treatment, respectively. Moreover, a significant correlation (P<0.01) between conjugated bilirubin and duration of total parenteral nutrition was established. Conclusions: Patients who were promptly treated with urso-deoxycholic acid showed a more rapid decrease in biochemical markers of cholestasis, but not of cytotoxicity in the hepatobiliary complications secondary to prolonged parenteral nutrition. However, the present study has limitations derived from its design and therefore it would be desirable launch a randomized trial with sufficient power to evaluate the benefits derived from prophylactic or therapeutic use of urso-deoxycholic acid in the hepatobiliary conditions associated with the prolonged use of parenteral nutrition in the premature infants (AU)

[Cholestasis associated with prolonged parenteral nutrition in neonates: the role of urso-deoxycholic acid]. / Colestasis asociada a la nutrición parenteral prolongada en el período neonatal: posible eficacia del ácido ursodesoxicólico.

INTRODUCTION: The morbidity associated with prematurity occasionally leads to the use of prolonged parenteral nutrition, with the subsequent development of cholestasis being one of its complications. PATIENTS AND METHODS: This is a two year retrospective study which compared biochemical markers of liver damage and cholestasis in premature babies who received or did not receive urso-deoxycholic acid for parenteral nutrition associated cholestasis. RESULTS: Of a total of 24 recruited patients 17 received urso-deoxycholic acid and 7 did not. In the treated group significant decreases (P<0.05) in gamma-glutamyltranspeptidase and conjugated bilirubin were found after four and five weeks of treatment, respectively. Moreover, a significant correlation (P<0.01) between conjugated bilirubin and duration of total parenteral nutrition was established. CONCLUSIONS: Patients who were promptly treated with urso-deoxycholic acid showed a more rapid decrease in biochemical markers of cholestasis, but not of cytotoxicity in the hepatobiliary complications secondary to prolonged parenteral nutrition. However, the present study has limitations derived from its design and therefore it would be desirable launch a randomized trial with sufficient power to evaluate the benefits derived from prophylactic or therapeutic use of urso-deoxycholic acid in the hepatobiliary conditions associated with the prolonged use of parenteral nutrition in the premature infants.

Psychological stress of parents of preterm infants enrolled in an early discharge programme from the neonatal intensive care unit: a prospective randomised trial.

BACKGROUND: Psychological stress of parents of preterm infants is aggravated by prolonged hospitalisation. Early discharge programmes (EDPs) have been implemented to alleviate this situation. OBJECTIVE: To evaluate parental psychological stress in an EDP for the first 3 months after neonatal intensive care unit (NICU) discharge. DESIGN/METHODS: Prospective randomised trial comparing parents of preterm infants assigned to EDP (n = 72) or standard discharge programme (SDP) (standard discharge) (n = 68). At discharge, parents were evaluated using the Hospital Anxiety and Depression Scale (HAD), and the Likert Scale for well-being every 10 days for 3 months. Parental narrative of Worrying and Helping issues was assessed using a semi-structured interview. RESULTS: Length of stay was greater in the SDP group (p<0.01). HAD showed no differences in anxiety, but SDP mothers scored higher in depression (p<0.05). Altogether, parents reported a worrisome emotional condition (EDP 87.2%; SDP 80%), which decreased at the end of the study (EDP 45.2%; SDP 34.5%). Their baby's physical well-being was the most relevant issue in the narrative for Worrying and Helping issues at discharge (EDP 69.2%; SDP 67.5%); however, it decreased at the end of the study (EDP 22.6%; SDP 24.1%). At discharge, the paediatrician's support was more for the SDP group. No differences on the Well-Being Scale were found, but the EDP group always scored better. CONCLUSIONS: Vulnerability of parents enrolled in an EDP did not increase after hospital discharge. Physical well-being of the baby was the most important issue for both groups. EDP parents requested less paediatric support and scored higher in the Well-being verbatim.

Carotid body oxygen sensing.

The carotid body (CB) is a neural crest-derived organ whose major function is to sense changes in arterial oxygen tension to elicit hyperventilation in hypoxia. The CB is composed of clusters of neuron-like glomus, or type-I, cells enveloped by glia-like sustentacular, or type-II, cells. Responsiveness of CB to acute hypoxia relies on the inhibition of O(2)-sensitive K(+) channels in glomus cells, which leads to cell depolarisation, Ca(2+) entry and release of transmitters that activate afferent nerve fibres. Although this model of O(2) sensing is generally accepted, the molecular mechanisms underlying K(+) channel modulation by O(2) tension are unknown. Among the putative hypoxia-sensing mechanisms there are: the production of oxygen radicals, either in mitochondria or reduced nicotinamide adenine dinucleotide phosphate oxidases; metabolic mitochondrial inhibition and decrease of intracellular ATP; disruption of the prolylhydroxylase/hypoxia inducible factor pathway; or decrease of carbon monoxide production by haemoxygenase-2. In chronic hypoxia, the CB grows with increasing glomus cell number. The current authors have identified, in the CB, neural stem cells, which can differentiate into glomus cells. Cell fate experiments suggest that the CB progenitors are the glia-like sustentacular cells. The CB appears to be involved in the pathophysiology of several prevalent human diseases.

Evaluación del riesgo nutricional e instauración de soporte nutricional en pacientes oncológicos, según el protocolo del grupo español de Nutrición y Cáncer / Nutricional risk evaluation and establishment of nutricional support in oncology patients according to the protocol of the spanish nutrition and cancer group

Introducción: El cáncer, los tratamientos que lo acompañan y los síntomas consecuentes que a su vez generan, aumentan en los pacientes el riesgo de sufrir malnutrición. La cual produce un gran deterioro del estado de salud, con el consecuente aumento de complicaciones, disminución de la tolerancia al tratamiento oncológico y una disminución de la calidad de vida del paciente. Por este motivo, un grupo de profesionales sanitarios de diferentes puntos de España se reunieron con el objetivo de mejorar la intervención nutricional en pacientes oncológicos, con el apoyo de la Sociedad Española de Nutrición Básica y Aplicada (SENBA). Metodología: Este grupo multidisciplinar de profesionales elaboró un documento de consenso basado en la literatura y en la experiencia personal, creando un protocolo de evaluación y de intervención nutricional en forma de algoritmos. Se clasifican los pacientes en tres pasos: 1. según el tipo de tratamiento oncológico que reciben, ya sea de tipo curativo o paliativo; 2. riesgo nutricional de la terapia antineoplásica (bajo, mediano, o alto riesgo), y 3. de acuerdo a la Valoración Global Subjetiva-Generada por el paciente (VGS-gp), que clasifica a los pacientes en: A. pacientes con adecuado estado nutricional, B. pacientes con malnutrición o a riesgo de malnutrición y C. pacientes con malnutrición severa. Durante un año el protocolo se puso en marcha en 226 pacientes mayores de 18 años de ambos sexos, escogidos al azar en las consultas externas de Radioterapia Oncológica y Oncología Médica. Resultados: Más de la mitad sufren malnutrición (64%), y este valor se incrementa llegando hasta un 81% en pacientes con tratamiento paliativo. La mayoría de los pacientes tienen tratamiento de intención curativa (83%) y reciben tratamiento oncológico de intensidad moderada o de alto riesgo nutricional (69%). Un 68% de los pacientes tienen algún tipo de dificultad en la alimentación. La media en el porcentaje de pérdida de peso es del 6,64% ± 0,87 (min 0, máx 33%). El 32% de la población presenta cifras de albúmina entre 3 y 3,5 g/dl, existiendo una correlación negativa entre ésta y las dificultades con la alimentación p = 0,001. El IMC no mostró ser un parámetro significativo para detectar malnutrición (sólo un 10% se encontraba por debajo de 19,9 kg/m2), pero tiene una tendencia lineal significativa con las dificultades en la alimentación, de forma tal que a medida que disminuye el IMC aumentan las dificultades p = 0,001. Más de la mitad de la población, requirió recomendaciones dietéticas específicas para el control de los síntomas que dificultaban la ingesta y una tercera parte de la población necesitó la indicación de suplementos nutricionales. Tras la intervención nutricional más de la mitad (60%) mantuvo su peso y una sexta parte lo aumentó. Conclusión: La aplicación de este protocolo es útil, sencillo y podría facilitar la detección de malnutrición en los pacientes oncológicos. Seleccionando a los pacientes que realmente se podrían beneficiar de una intervención nutricional específica, pero debería aplicarse al inicio coincidiendo si fuera posible con el diagnóstico de la enfermedad. El soporte nutricional resulta eficaz en la mayoría de los pacientes (AU)

Introduction: Cancer and its oncological treatment cause symptoms which increase the patients risk to suffer from malnutrition. This affects the patients health status negatively by increasing the number of complications, reducing the tolerance to the oncology treatment and a decrease of the patients quality of life. Motivated by this, a group of health professionals from several spanish regions met with the backing of the Sociedad Española de Nutrición Básica y Aplicada (SENBA) to address strategies to improve the quality of nutritional intervention in cancer patients. Methods: This multidisciplinary group developed a protocol describing nutritional assessment and intervention in form of algorithms based on literature and personal experience. The patients are classified in a three step process: 1. type of their oncology treatment (curative or palliative); 2. nutritional risk of the antineoplastic therapy (low, medium or high risk) and 3. depending on the Subjective Global Assessment patient-generated (SGApg). The patients are classified as: A. patients with adequate nutritional state, B. patients with malnutrition or risk of malnutrition and C. patients suffering from severe malnutrition. During one year, the protocol has been used for 226 randomly chosen female and male patients older than 18 years. They were treated by the Medical and Radiotherapy Oncology outpatient clinic. Results: More than a half of the patients were suffering from malnutrition (64%) increasing up to 81% for patients undergoing palliative treatment. Most of them were treated curatively (83%) and received oncology treatment with moderate or high nutritional risk (69%). 68% of patients were affected by some feeding difficulty. The mean percentage of weight loss has been 6.64% ± 0.87 (min 0%, max 33%). Albumin values of 32% of the patients were between 3 and 3.5 g/dl and negatively correlated with feeding difficulties (p = 0.001). The body mass index (BMI) has not found to be a significant parameter for detecting malnutrition (only in 10% of the patients, the value was below 19.9 kg/m2). But a significant linear tendency when compared to feeding problems could be shown, such that in patients with less feeding problems a higher BMI has been found (p = 0.001). More than a half of the patients required nutritional counselling to control symptoms which made food intake difficult. One third of the patients needed oral nutritional supplementation. Following the nutritional intervention the weight of about 60% of the patients could be maintained and of one sixth it could be increased. Conclusion: The application of this protocol is useful, easy and could help detecting malnutrition in oncology patients. It provides the possibility to select those patients who can benefit from a specific nutritional intervention. If possible, the application of the protocol should be started immediatly after cancer is diagnosed. Nutritional support proves efficient for most of the patients (AU)

Cardiovascular disease in familial hypercholesterolaemia: influence of low-density lipoprotein receptor mutation type and classic risk factors.

AIM: To determine the effect of the type of mutation in low-density lipoprotein receptor gene and the risk factors associated with the development of premature cardiovascular disease (PCVD) in a large cohort of heterozygous familial hypercholesterolemia (hFH) subjects with genetic diagnosis in Spain. METHODS AND RESULTS: A cross-sectional study was conducted on 811 non-related FH patients (mean age 47.1+/-14 years, 383 males and 428 females) with a molecular defect in the low-density lipoprotein receptor (LDLR) gene from the Spanish National FH Register. Prevalence of PCVD was 21.9% (30.2% in males and 14.5% in women, P<0.001). Mean age of onset of cardiovascular event was 42.1 years in males and 50.8 years in females. Of those patients with PCVD, 59.5% of males and 27% of females suffered a second cardiovascular (CV) event. In multivariate analysis male gender, age, tobacco consumption (ever), and total cholesterol/HDL-cholesterol (TC/HDL-C) ratio were significantly associated with PCVD. Two hundred and twenty different mutations were found with a large heterogeneity. Patients carrying null-mutations had significantly higher frequency of PCVD and recurrence of CV events. No relationship with Lp(a) levels and genotype of Apo E were found. CONCLUSIONS: This study confirms the importance of identifying some classic risk factors such as smoking and TC/HDL-C ratio, and also the type of mutation in LDLR gene in order to implement early detection and intensive treatment for the prevention of cardiovascular disease in FH patients.

[Nutritional risk evaluation and establishment of nutritional support in oncology patients according to the protocol of the Spanish Nutrition and Cancer Group]. / Evaluación del riesgo nutricional e instauración de soporte nutricional en pacientes oncológicos, según el protocolo del grupo Español de Nutrición y Cáncer.

INTRODUCTION: Cancer and its oncological treatment cause symptoms which increase the patients risk to suffer from malnutrition. This affects the patients health status negatively by increasing the number of complications, reducing the tolerance to the oncology treatment and a decrease of the patients quality of life. Motivated by this, a group of health professionals from several spanish regions met with the backing of the Sociedad Española de Nutrición Básica y Aplicada (SENBA) to address strategies to improve the quality of nutritional intervention in cancer patients. METHODS: This multidisciplinary group developed a protocol describing nutritional assessment and intervention in form of algorithms based on literature and personal experience. The patients are classified in a three step process: 1. type of their oncology treatment (curative or palliative); 2. nutritional risk of the antineoplastic therapy (low, medium or high risk) and 3. depending on the Subjective Global Assessment patient-generated (SGA-pg). The patients are classified as: A. patients with adequate nutritional state, B. patients with malnutrition or risk of malnutrition and C. patients suffering from severe malnutrition. During one year, the protocol has been used for 226 randomly chosen female and male patients older than 18 years. They were treated by the Medical and Radiotherapy Oncology outpatient clinic. RESULTS: More than a half of the patients were suffering from malnutrition (64%) increasing up to 81% for patients undergoing palliative treatment. Most of them were treated curatively (83%) and received oncology treatment with moderate or high nutritional risk (69%). 68% of patients were affected by some feeding difficulty. The mean percentage of weight loss has been 6.64% +/- 0.87 (min 0%, max 33%). Albumin values of 32% of the patients were between 3 and 3.5 g/dl and negatively correlated with feeding difficulties (p = 0.001). The body mass index (BMI) has not found to be a significant parameter for detecting malnutrition (only in 10% of the patients, the value was below 19.9 kg/m2). But a significant linear tendency when compared to feeding problems could be shown, such that in patients with less feeding problems a higher BMI has been found (p = 0.001). More than a half of the patients required nutritional counselling to control symptoms which made food intake difficult. One third of the patients needed oral nutritional supplementation. Following the nutritional intervention the weight of about 60% of the patients could be maintained and of one sixth it could be increased. CONCLUSION: The application of this protocol is useful, easy and could help detecting malnutrition in oncology patients. It provides the possibility to select those patients who can benefit from a specific nutritional intervention. If possible, the application of the protocol should be started immediatly after cancer is diagnosed. Nutritional support proves efficient for most of the patients.

Identification of Plum pox virus pathogenicity determinants in herbaceous and woody hosts.

Plum pox virus (PPV) is a member of the genus Potyvirus that is able to infect a large variety of plant species, including trees of the genus Prunus, its natural host. When some PPV isolates are propagated for an extended time in herbaceous plants, their ability to infect trees is reduced. The molecular basis of this change in host infectivity is poorly understood. We report the construction of hybrid viruses from cDNA clones of two D-strain isolates of PPV, PPV-D and PPV-R, which differ in their host range. PPV-D can infect GF305 peach seedlings efficiently, however, it is unable to infect Nicotiana clevelandii plants. Conversely, PPV-R infects N. clevelandii, but not GF305 peach seedlings. The analyses of the hybrid viruses showed that, although determinants of PPV pathogenicity are extensively spread throughout the PPV genome, the 3' terminal region of the PPV-R genome, including the 3' noncoding region and the coding regions for the coat protein (CP), NIb, and part of NIa protein, is sufficient to confer infectivity of N. clevelandii in a PPV-D background. Our data demonstrate a high concentration of amino acid substitutions in the CP and a host-specific effect of a deletion at the N terminus of this protein in PPV pathogenicity in peach and N. clevelandii infectivity experiments. These results suggest that relevant host specificity determinants are located in the N-terminal region of the CP. The analyses of the PPV-R and PPV-D chimeras also showed that key host-specific pathogenicity determinants lie in the 5' terminal third of the PPV genome, a region that spans proteins P1, HCPro, and P3. The selection of mutations in only a few specific residues in proteins P1, P3, and 6K1 after partial adaptation of a chimeric virus (BD-GFP) to N. clevelandii further suggests a relevant role for these proteins in host adaptation.

Haemolysis alters plasma flecainide levels in newborn infants.

Refractory neonatal supra-ventricular tachycardia may require the use of flecainide as anti-arrhythmic. Close control of plasma levels is mandatory due to pro-arrhythmic complications. However, inadvertent hemolysis during blood sampling may cause an increase in measured plasma flecainide concentrations. We conclude, therefore, that dosing of the drug should be always done with caution, and in case of suspected haemolysis plasma levels should be repeated with a new blood sample.

Pathogenicity determinants in the complex virus population of a Plum pox virus isolate.

Several subisolates were separated from a single Plum pox virus (PPV) isolate, PPV-PS. In spite of an extremely high sequence conservation (more than 99.9% similarity), different subisolates differed largely in pathogenicity in herbaceous hosts and infectivity in woody plants. The severity of symptomatology did not seem to correlate with virus accumulation. Sequence analysis and site-directed mutagenesis demonstrated that single amino acid changes in the helper component (HC) protein caused a drastic effect on virus symptoms in herbaceous hosts and notably modified virus infectivity in peach seedlings. These results indicate that HC variation might play an important role in virulence evolution of natural plant virus infections. Moreover, the analysis of Potato virus X (PVX)-HC chimeras showed that the identified HC amino acid changes had parallel effects on the severity of symptoms caused by PPV and on HC-induced enhancement of PVX pathogenicity, indicating that HC functions in potyvirus symptomatology and in synergism with other viruses have overlapping determinants.

Cellular mechanism of oxygen sensing.

O2 sensing is a fundamental biological process necessary for adaptation of living organisms to variable habitats and physiological situations. Cellular responses to hypoxia can be acute or chronic. Acute responses rely mainly on O2-regulated ion channels, which mediate adaptive changes in cell excitability, contractility, and secretory activity. Chronic responses depend on the modulation of hypoxia-inducible transcription factors, which determine the expression of numerous genes encoding enzymes, transporters and growth factors. O2-regulated ion channels and transcription factors are part of a widely operating signaling system that helps provide sufficient O2 to the tissues and protect the cells against damage due to O2 deficiency. Despite recent advances in the molecular characterization of O2-regulated ion channels and hypoxia-inducible factors, several unanswered questions remain regarding the nature of the O2 sensor molecules and the mechanisms of interaction between the sensors and the effectors. Current models of O2 sensing are based on either a heme protein capable of reversibly binding O2 or the production of oxygen reactive species by NAD(P)H oxidases and mitochondria. Complete molecular characterization of the hypoxia signaling pathways will help elucidate the differential sensitivity to hypoxia of the various cell types and the gradation of the cellular responses to variable levels of PO2. A deeper understanding of the cellular mechanisms of O2 sensing will facilitate the development of new pharmacological tools effective in the treatment of diseases such as stroke or myocardial ischemia caused by localized deficits of O2.

Identification of Plum pox virus Determinants Implicated in Specific Interactions with Different Prunus spp.

ABSTRACT The characterization of pathogenic properties of two infectious clones of Plum pox virus (PPV) isolates, pGPPV (D group) and pGPPVPS (M group), was investigated in their woody hosts (seedlings of Prunus spp.). The two clones differed in their ability to infect plum and peach cultivars, from no infection to local and systemic infection. The phenotype determinants were located with a set of chimeric viruses from the two clones. In plum, determinants of systemic infection were located in a genomic fragment encoding the P3 and 6K1 proteins, which might influence genome amplification or virus movement. The capacity of pGPPVPS to induce stable local and systemic infections in peach was not located accurately and might be influenced by multiple determinants carried by different regions of the genome, excluding those encoding the protein 1, the majority of helper component, nuclear inclusions a and b, and coat protein. We conclude that PPV infections of plum and peach are governed by different determinants.