Repeated toluene and cyclohexane inhalation produces differential effects on HPA and HPT axes in adolescent male rats.

Misused volatile solvents typically contain toluene (TOL) as the main psychoactive ingredient. Cyclohexane (CHX) can also be present and is considered a safer alternative. Solvent misuse often occurs at early stages of life, leading to permanent neurobehavioral impairment and growth retardation. However, a comprehensive examination of the effects of TOL and CHX on stress regulation and energy balance is lacking. Here, we compared the effect of a binge-pattern exposure to TOL or CHX (4,000 or 8,000 ppm) on body weight, food intake, the hypothalamus-pituitary-adrenal (HPA) and hypothalamus-pituitary-thyroid (HPT) axes in male adolescent Wistar rats. At 8,000 ppm, TOL decreased body weight gain without affecting food intake. In addition, TOL and CHX altered the HPA and HPT axes' function in a solvent- and concentration-dependent manner. The highest TOL concentration produced HPA axis hyperactivation in animals not subjected to stress, which was evidenced by increased corticotropin-releasing-factor (CRF) release from the median eminence (ME), elevated adrenocorticotropin hormone (ACTH) and corticosterone serum levels, and decreased CRF mRNA levels in the hypothalamic paraventricular nucleus (PVN). TOL (8,000 ppm) also increased triiodothyronine (T3) serum levels, decreased pro-thyrotropin-releasing-hormone (pro-TRH) mRNA transcription in the PVN, pro-TRH content in the ME, and serum thyroid stimulating hormone (TSH) levels. CHX did not affect the HPA axis. We propose that the increased HPT axis activity induced by TOL can be related to the impaired body weight gain associated with inhalant misuse. These findings may contribute to a better understanding of the effects of the misused solvents TOL and CHX.

[Treatment of the pelvic floor in males with incomplete spinal cord injury: a systematic review].

Pelvic floor disorders are one of the most common complications in male patients with spinal cord injury. The aim of this review was to analyse the available evidence on the efficacy of different treatments used for pelvic floor dysfunctions in men with incomplete spinal cord injuries. The Scopus, Medline, PEDro, Web of Science, Dialnet, Pubmed and Cochrane databases were consulted for papers in Spanish and English published in the last twenty years. Fifteen articles were included, comprising a total of 706 male patients with incomplete spinal cord injury. In male patients with neurogenic bladder and erectile dysfunction, the best results were obtained with neuromodulation and combined treatments (electrotherapy or acupuncture / electroacupuncture with catheterization or bladder training).

Tratamiento complementario de la fibrosis quística con terapia acuática. A propósito de un caso / Supplementary treatment of cystic fibrosis with hydrotherapy. A case report

Antecedentes y objetivo: La fibrosis quística (FQ) produce una afectación multisistémica, por lo que la hidroterapia puede aportar numerosos beneficios en su tratamiento. El objetivo de este estudio es la presentación de la efectividad de un programa de hidroterapia en una paciente pediátrica con FQ. Descripción del caso: Niña de 23 meses de edad con FQ que presenta dificultad respiratoria. Intervención: El programa de tratamiento consiste en la realización de 5 sesiones de hidroterapia de 30 min de duración cada una. Resultados: Se muestran mejoras en los signos vitales y las capacidades de la paciente (movilización de secreciones y expectoración), generando efectos positivos sobre su calidad de vida. Discusión: Otros autores han relacionado este tipo de tratamiento con trastornos respiratorios en edades pediátricas y en edad adulta, confirmando igualmente los beneficios que se han obtenido en el caso clínico planteado

Background and objective: Cystic Fibrosis (CF) leads to a multisystemic involvement. Hydrotherapy shows many positive effects. The aim of this study is to show the effectiveness of a hydrotherapy program in a patient with CF. Case description: The patient is a 23 month-old girl with CF and respiratory distress. Intervention: The treatment program consisted of the fulfilment of five 30-minute hydrotherapy sessions. Results: There was an improvement in in patient vital signs and capacities (mainly in terms of mobilisation of secretions and expectoration), generating positive effects on her quality of life. Discussion: Other authors have associated this type of treatment with respiratory disorders, and have confirmed its benefits in paediatric and adult patients, including those obtained in the case presented

Efectos de un programa de prevención de caídas con Ai Chi acuático en pacientes diagnosticados de parkinson / Effects of an Ai Chi fall prevention programme for patients with Parkinson's disease

Introducción: Un síntoma principal de la enfermedad de Parkinson es la alta incidencia en caídas y deterioro en el equilibrio, tanto estático como dinámico. El objetivo de este estudio es determinar el efecto de un programa de entrenamiento de Ai Chi acuático sobre la prevención de caídas en pacientes con Parkinson, mejorando su autonomía funcional y su percepción del dolor físico. Método: Quince pacientes diagnosticados de Parkinson (Hoehn y Yahr, rango: 1-3) participaron en un programa de intervención de Ai Chi acuático de 10 semanas de duración, con sesiones 2 veces por semana. Se emplearon las escalas EVA de dolor, Tinetti de equilibrio y marcha y el test Get up and Go. Resultados: Los resultados se obtuvieron aplicando la prueba de Friedman para 3 muestras relacionadas, en los pacientes antes de la terapia, después de la terapia y al mes de la terapia. Los datos obtenidos mostraron una mejoría significativa (p < 0,001) al comparar los resultados mostrados en las 3 mediciones, donde los valores de percepción de dolor, equilibrio y funcionalidad en marcha han disminuido significativamente, incluso al mes de finalizar las mismas los pacientes seguían mostrando mejoría y mantenimiento en sus resultados. Conclusión: Un programa de Ai Chi en el agua parece ser un tratamiento factible para los pacientes diagnosticados con EP en un grado leve y moderado en el tratamiento del dolor, equilibrio y capacidad funcional

Introduction: One of the main symptoms of Parkinson's disease is the high incidence of falls occurring due to the decline of both static and dynamic balance. The aim of this study is to determine the effect of an Ai Chi programme designed to prevent falls in patients with Parkinson's disease by improving both functional independence and perception of physical pain. Methods: Fifteen patients diagnosed with Parkinson's disease (Hoehn and Yahr stages 1-3) participated in a 10-week Ai Chi programme consisting of 30 to 45-minute aquatic exercise sessions twice a week. The assessment measures used in this study were the pain visual analogue scale (VAS), the Tinetti gait and balance assessment tool, and the Timed Get up and Go test. Results: The results were calculated by applying the Friedman test to 3 related measurements: patients at baseline, at post-treatment (at the end of the 10 week programme) and after one month of follow-up. The data obtained showed a significant improvement (p < .001) in scores for pain perception, balance, and gait function after the treatment programme. Furthermore, patients continued to show significant improvements and the benefits remained at the one-month follow-up visit. Conclusion: Ai Chi is a promising and feasible aquatic treatment for improving pain perception, balance, and functional capacity in patients diagnosed with mild or moderate Parkinson's disease

Development of combinations of chemically modified vegetable oils as pork backfat substitutes in sausages formulation.

Today's consumers look for foods which provide nutrition and pleasure, while safeguarding their health, the result of which is that they increasingly avoid foods containing cholesterol and saturated and trans fatty acids. Chemically modified vegetable oils can help tailor meat products to meet this growing need and at the same time fulfil the technological needs of the meat processing industry. In this study, 16 backfat samples were characterised for their solid fat content (SFC) and melting point and these characteristics were used to design a mixture of chemically modified vegetable oils for use as a pork fat substitute for elaborating sausages. The mixtures were prepared with different vegetable oils bearing in mind with stearic acid content due to its close correlation with the SFC. The backfat was characterised as a function of its SFC and some modified vegetable oil mixtures were proposed, which led to a 10-20% diminution in saturated fatty acids and with a melting point similar to those observed in the backfat. The fatty acid profile pointed to a polyunsaturated/saturated fatty acids ratio higher than 0.4, and an n-6/n-3 fatty acid ratio of less than 4 in both modified vegetable oil mixtures proposed.

Esclerosis múltiple y técnicas de relajación / Multiple sclerosis and relaxation technique

Objetivos: Realizar un análisis bibliográfico de las corrientes de tratamiento en técnicas de relajación más efectivas y utilizadas en la esclerosis múltiple y ver qué técnica/s en concreto muestra/n mayor grado de efectividad.Material y métodosSe consultaron las siguientes fuentes de datos: Cochrane Library Plus, PEDro, LILACS, Medline, CINAHL, Bandolier, AMED, EMBASE, PsychINFO, Psycharticles, AMA. Para ello se seleccionaron ensayos clínicos controlados y aleatorios, cuyos integrantes eran personas con un diagnóstico definido de esclerosis múltiple y que fueron sometidas a técnicas de relajación.ResultadosSe localizaron treinta y cinco artículos en las bases de datos mencionadas anteriormente, sólo dos fueron incluidos en esta revisión.ConclusiónSe puede decir que, potencialmente, las técnicas de relajación (yoga y entrenamiento autógeno, concretamente) pueden brindar beneficios en diferentes dimensiones de la enfermedad (vitalidad, fatiga, depresión), pudiendo mejorar su calidad de vida (A)

To analyze the bibliography on the treatment trends in those relaxation techniques that are the most effective and used in multiple sclerosis and to discover which techniques show the greatest degree of efficiency.Material and methodsWe consulted the following data sources: Cochrane Library Plus, PEDro, LILACS, Medline, CINAHL, Bandolier, AMED, Embase, Psychinfo, Psycharticles, AMA. Selection of studies. Randomized controlled clinical trials, that included subjects with a definite diagnosis of multiple sclerosis and who were subjected to relaxation techniques were selected.ResultsThirty-five articles were located in the previously-mentioned databases but only two have been included in this review.ConclusionPotentially, it could be stated that relaxation techniques (yoga and autogenic training, in particular) may provide benefits in different dimensions of the disease (vitality, fatigue, depression) and may improve quality of life (AU)

[Self-perception of cancer patients on the relationship existing between their nutritional status, their feeding status, and their illness]. / Autopercepción de los pacientes con cáncer sobre la relación existente entre su estado nutricional, su alimentación y la enfermedad que padecen.

INTRODUCTION: Knowing the opinion of oncologic patients about the importance they give to their feeding, the difficulties they have with feeding, their body image, weight, and ponderal changes, the relationship between their feeding and their illness, the relationship between their physical activity and their mood and health is essential to look for nutritional therapeutic interventions leading to improvement of quality of life and, in general, the feeling of well being. Thus, it is paramount to know the patients' opinion of these issues. MATERIAL AND METHODS: We passed a questionnaire to 131 patients. The patients were recruited from the Day-Hospital of the Medical Oncology and Radiotherapeutic Oncology Departments, and from the Hospitalization Department of Medical Oncology. In the questionnaire, we asked in a simple manner about the importance the patients give to all these issues. This is a 20-item questionnaire, divided into six parts: 1. Vital statistics; 2) perception about the disease and its relationship with feeding; 3) Perception of the relationship between physical activity and mood with feeding; 4) Nutritional therapies prescribed to the patients and their perception on its effect on the disease progression; 5) Current difficulties with feeding; 6) Demand of nutritional care. RESULTS: The patients mean age was 57 +/- 13 years. 45% were males, and the remaining females. 81% life in an urban area, and only 14% in a rural area. The educational level was categorized in 5 groups: without education, basic education, elementary school, high school, or college studies. 28% had basic education, and 19% college studies, and only 8% had no education at all. Their occupation was also categorized in five groups: home-keeping, student, unemployed, employed, and retired. 33% were employed, 29% retired, and 34% were home-keepers. Most of the patients (74%) are aware of their illness and perceive it as severe or very much severe. Most of these patients worry about their body image, weight, and ponderal changes, and they relate them with their feeding status. 74% find a relationship between their nutritional status and their physical activity, and 73% relate it with their mood. At least half of the patients perceive their mood as being low. Although 47% manifested having some difficulty for feeding, only 34% had received some information about their diet, 26% had consumed nutritional supplements, and 81% still consumed their diet without any change. The most common difficulties for feeding were decreased appetite (38%), early satiety (32%), and nausea (20%). The nutritional intervention most commonly required by the patients was general and specific nutritional education to alleviate the symptoms associated to oncologic therapies. CONCLUSIONS: Most of the patients are aware of the severity of their illness and care about their body image, weight, and ponderal changes, which they associate with their nutrition. Most of the patients find a close relationship between their nutritional status, their physical activity and their mood. More than half of the patients manifest having some difficulty feeding, but only one third of the population has received information about their diet some time. It is clearly shown that oncologic patients need different effective nutritional intervention measures contributing to improve their feeling of well being.

Evaluación de la toxicidad aguda y la acción hipolipemiante del aceite de Plukenetia volúbilis, Sacha Inchi / Evaluation of acute toxicity and hypolipemic action of Plukenetia volúbilis, Sacha Inchi

Se evaluó el efecto tóxico agudo del aceite de Plukenetia volúbilis (Sacha Inchi), determinando la Dosis Letal -50 (DL50) en 42 ratones de la cepa Nish, distribuidos en siete grupos de seis ratones cada uno, a los cuales se les administró, vía oral, dosis crecientes del aceite. Para evaluar el efecto hipolipemiante utilizamos 55 ratas albinas machos de la raza Holtzman, con un peso entre 194 g y 290 g y dos meses de edad. Se utilizó una dieta con 15 por ciento de grasas saturadas para elevar los lípidos séricos durante todo el tiempo del experimento. Utilizamos tres dosis diferentes de aceite de Sacha Inti, administradas durante 14 días consecutivos, comparando sus efectos con un control positivo (Lovastatina) y un control negativo (SF). Se controló el peso de los animales y los valores de colesterol, HDL y triglicéridos sanguíneos en tres tiempos diferentes. El análisis estadístico se realizó mediante el programa STATA 8.2. La DL50 fue de 111,65 mg/kg; hubo una reducción significativa de los valores sanguíneos de triglicéridos y LDL, mas no de colesterol y peso de los animales.

The acute toxic of Plukenetia volúbilis (Sacha Inchi) oil was evaluated. We calculated the Medial Lethal Dose (DL50) on 42 mice of the Nish strain, distributed in seven groups of six mice each, to whom a different and increasing dose was administered by oral route. To determine the hypolipidemic effect, we used 55 male albino rats of the Holtzman breed, whose weight fluctuateed between 194 and 290 g. The animals were fed with 15% of a saturateed fat diet for 14 days to produce hyperlipidemia during the whole period of the experiment. Treatment with Sacha Inchi oil in three different doses during 14 consecutive days was compared to the effects of a positive (lovastatine) and a negative control (physiological serum). The weight, cholesterol, HDL, LDL, VLDL, and triglycerides, were controlled in three different periods of time. Statistics analysis was made using the STATA 8.2 program. The DL50 was detrmined at 111,65 mg/Kg and the level of tryclicerides and LDL were statistically reduced, but not the cholesterol values or the animals' weight.

Effect of piperine on the epididymis of adult male rats.

AIM: To study the effect of piperine on the epididymal antioxidant system of adult male rats. METHODS: Adult male rats were orally administered piperine at doses of 1 mg/kg, 10 mg/kg and 100 mg/kg body weight each day for 30 consecutive days. Twenty-four hours after the last treatment, the rats were weighed and killed with ether and the epididymis was dissected from the bodies. Sperm collected from the cauda region of the epididymis was used for the assessment of its count, motility and viability. Caput, corpus and cauda regions of the epididymis were separated and homogenized separately to obtain 10 % homogenates. The supernatants were used for the assays of sialic acid, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, lipid peroxidation and hydrogen peroxide generation. RESULTS: Body weight of the piperine-treated rats remained unchanged. The weights of the caput, corpus and cauda regions of the epididymis significantly decreased at dose of 100 mg/kg. Epididymal sperm count and motility decreased at 10 mg/kg and 100 mg/kg, and sperm viability decreased significantly at 100 mg/kg. Sialic acid levels in the epididymis decreased significantly at 100 mg/kg while significant decrease in the cauda region alone was observed at 10 mg/kg. A significant decline in the activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase, along with an increase in hydrogen peroxide generation and lipid peroxidation were observed at 10 mg/kg and 100 mg/kg. CONCLUSION: Piperine caused a decrease in the activity of antioxidant enzymes and sialic acid levels in the epididymis and thereby increased reactive oxygen species levels that could damage the epididymal environment and sperm function.

Úlcera corneal bilateral como consecuencia de malnutrición calóricoprotéica y déficit de vitamina A en un paciente con alcoholismo crónico, pancreatitis crónica y colecistostomía / Bilateral corneal ulceration as a result of energy-protein hyponutrition and vitamin a deficit in a patient with chronic alcoholism, chronic pancreatitis and cholecystostomy

Desde el descubrimiento de las vitaminas ha existido un creciente interés por relacionar las vitaminas con ciertas enfermedades. Para la vitamina A en particular se ha determinado su singular importancia en múltiples funciones vitales y su relación con enfermedades tanto por déficit como por exceso esta ahora completamente demostrada. En países desarrollados las enfermedades por déficit vitamínicos han disminuido de manera importante; sin embargo en pacientes con características particulares deben tenerse siempre presente. Se trata de un hombre de 45 años, con antecedentes de alcoholismo crónico, pancreatitis crónica, diabetes mellitus no insulinodependiente y colecistostomía con alto drenaje biliar secundario a colecistitis enfisematosa y absceso perivesicular. Consulta por dolor ocular bilateral, fotofobia y disminución de la agudeza visual además de una historia de heces pastosas, pegajosas y malolientes. Ingresa a cargo de Oftalmología y diagnostican úlcera córneal bilateral. Cursan una interconsulta al Servicio de Nutrición por presencia de caquexia. Se detecta malnutrición calórica severa y proteica leve con IMC de 18,2 y pérdida del 23% de su peso habitual en los últimos 6 meses, déficit de vitaminas liposolubles (A, D y E), malabsorción grasa leve y anemia macrocítica é hipocrómica. Suplementamos la dieta del paciente con una formula hiperproteica e hipercalórica especial para diabéticos, se administran las vitaminas deficitarias, enzimas pancreáticas para mejorar la malabsorción y se controlan las glucemias con insulina. Cuatro meses después paciente es evaluado y presenta un IMC de 20, la anemia esta resuelta y desde el punto de vista oftalmológico evoluciona favorablemente, las ulceras mejoran y la agudeza visual se recupera casi por completo. En pacientes alcohólicos crónicos con un nivel bajo de ingesta y complicaciones clínicas con repercusiones nutricionales (pancreatitis que produce malabsorción o colecistostomia con drenaje biliar percutáneo) no debemos olvidar que los déficits de micronutrientes pueden explicar la etiología de otras patologías asociadas en este caso las ulceras cornéales (AU)

Since the discovery of vitamins, there has been an increasing interest at relating vitamins with particular diseases. In particular, for vitamin A its singular importance has been determined in multiple vital functions, and its relationship with diseases, both in deficit and in excess, is nowadays completely demonstrated. In developed countries, vitamin deficiency-related diseases have been greatly reduced; however, in some patients with particular features they must be kept in mind. This is the case of a 45 year-old man, with a history of chronic alcoholism, non insulin-dependent diabetes mellitus and cholecystectomy with a high biliary drainage secondary to emphysematous cholecystitis and perivesicular abscess. He complains of bilateral ocular pain, photophobia, and decreased visual acuity besides a history of pasty, sticky and foul-smelling feces. He is admitted in the Ophthalmology Department and bilateral corneal ulceration is diagnosed. A consultation to the Nutrition Department is made because of cachexia. Severe caloric and mil protein hyponutrition is observed with a BMI of 18.2 and a 23% weight loss for the last 6 months, fat-soluble vitamins (A, D and E) deficit, mild fat malabsorption, and macrocytic and hypochromic anemia. The patient's diet is supplemented with a special hyperproteinic and hypercaloric diet for diabetics, deficient vitamins and pancreatic enzymes to improve absorption are administered, and glycemia is controlled with insulin. Four months later, the patient is assessed and has a BMI of 20, anemia has resolved and from an ophthalmologic viewpoint the course is favorable, the ulcers improve and visual acuity is almost completely recovered. In chronic alcoholic patients with a low dietary intake and clinical complications with nutritional repercussions (pancreatitis that produces malabsorption or cholecystectomy with biliary percutaneous drainage) we should not forget that micronutrients deficits may explain the etiology of other associated diseases, in the present case corneal ulceration (AU)

[Bilateral corneal ulceration as a result of caloric-protein malnutrition and vitamin A deficit in a patient with chronic alcoholism, chronic pancreatitis and cholecystostomy]. / Ulcera corneal bilateral como consecuencia de malnutrición calórico- protéica y déficit de vitamina A en un paciente con alcoholismo crónico, pancreatitis crónica y colecistostomía.

Since the discovery of vitamins, there has been an increasing interest at relating vitamins with particular diseases. In particular, for vitamin A its singular importance has been determined in multiple vital functions, and its relationship with diseases, both in deficit and in excess, is nowadays completely demonstrated. In developed countries, vitamin deficiency-related diseases have been greatly reduced; however, in some patients with particular features they must be kept in mind. This is the case of a 45 year-old man, with a history of chronic alcoholism, non insulin-dependent diabetes meIlitus and cholecystectomy with a high biliary drainage secondary to emphysematous cholecystitis and perivesicular abscess. He complains of bilateral ocular pain, photophobia, and decreased visual acuity besides a history of pasty, sticky and foul-smelling feces. He is admitted in the Ophthalmology Department and bilateral corneal ulceration is diagnosed. A consultation to the Nutrition Department is made because of cachexia. Severe caloric and mil protein hyponutrition is observed with a BMI of 18.2 and a 23% weight loss for the last 6 months, fat-soluble vitamins (A, D and E) deficit, mild fat malabsorption, and macrocytic and hypochromic anemia. The patient's diet is supplemented with a special hyperproteinic and hypercaloric diet for diabetics, deficient vitamins and pancreatic enzymes to improve absorption are administered, and glycemia is controlled with insulin. Four months later, the patient is assessed and has a BMI of 20, anemia has resolved and from an ophthalmologic viewpoint the course is favorable, the ulcers improve and visual acuity is almost completely recovered. In chronic alcoholic patients with a low dietary intake and clinical complications with nutritional repercussions (pancreatitis that produces malabsorption or cholecystectomy with biliary percutaneous drainage) we should not forget that micronutrients deficits may explain the etiology of other associated diseases, in the present case corneal ulceration.

Smooth muscle relaxing compounds from Dodonaea viscosa.

Bioassay-directed fractionation of the chloroform-methanol (1:1) extract of Dodonaea viscosa (L.) Jacq. (Sapindaceae) resulted in the isolation of four active spasmolytic principles: sakuranetin (1), 6-hydroxykaempferyl 3,7-dimethyl ether (2) hautrivaic acid (3), and ent-15, 16-epoxy-9 alpha H-labda-13(16)14-diene-3 beta, 8 alpha-diol (4). All the isolated compounds elicited a concentration-dependent inhibition of the spontaneous and electrically-induced contractions of guinea-pig ileum. Sakuranetin and the ent-labdane inhibited ileum contractions evoked by acetylcholine (Ach), histamine, and barium chloride. In addition, both substances were capable of relaxing contractions of rat uterus induced by Ca2+ in K(+)-depolarizing solution, displacing to the right the concentration-response curves to Ca2+. These results suggest that sakuranetin and ent-15,16-epoxy-9 alpha H-labda-13(16)14-diene-3 beta, 8 alpha-diol produce an interference with calcium metabolism in smooth muscle cells. The spasmolytic activity exhibited by the active principles from D. viscosa, provides the pharmacological basis for the traditional use of the plant as an antispasmodic agent.

Analysis of potato virus X coat protein genes in relation to resistance conferred by the genes Nx, Nb and Rx1 of potato.

The coat protein gene nucleotide sequences from eight previously uncharacterized strains of potato virus X (PVX) were determined. Comparison of the deduced amino acid sequences showed that two classes of PVX coat protein, designated types X and B, could be distinguished based on protein length and overall amino acid identities. In all there were 14 amino acid positions where all of the type X proteins differed from all of the type B proteins. The PVX coat protein is the principal viral determinant of the outcome of interactions between the virus and potatoes carrying either the Nx or Rx1 resistance genes. The different strains of PVX were tested for their ability to overcome resistance conferred by three potato resistance genes: Nx, Nb and Rx1. All of the strains that were avirulent on potato cultivars carrying the Nx resistance gene were found to have type X coat proteins whereas strains capable of overcoming the Nx resistance had type B coat proteins.

Jellyfish green fluorescent protein as a reporter for virus infections.

The gene encoding green fluorescent protein (GFP) of Aequorea victoria was introduced into the expression cassette of a virus vector based on potato virus X (PVX). Host plants of PVX inoculated with PVX.GFP became systemically infected. Production of GFP in these plants was detected initially between 1 and 2 days postinoculation by the presence of regions on the inoculated leaf that fluoresced bright green under UV light. Subsequently, this green fluorescence was evident in systemically infected tissue. The fluorescence could be detected by several methods. The simplest of these was by looking at the UV-illuminated plants in a darkened room. The PVX.GFP-infected tissue has been analysed either by epifluorescence or confocal laser scanning microscopy. These microscopical methods allow the presence of the virus to be localized to individual infected cells. It was also possible to detect the green fluorescence by spectroscopy or by electrophoresis of extracts from infected plants. To illustrate the potential application of this reporter gene in virological studies a derivative of PVX.GFP was constructed in which the coat protein gene of PVX was replaced by GFP. Confocal laser scanning microscopy of the inoculated tissue showed that the virus was restricted to the inoculated cells thereby confirming earlier speculation that the PVX coat protein is essential for cell-to-cell movement. It is likely that GFP will be useful as a reporter gene in transgenic plants as well as in virus-infected tissue.

Spasmolytic potential of some plants used in Mexican traditional medicine for the treatment of gastrointestinal disorders.

The present investigation describes the effect on the isolated rat ileum of methanolic extracts derived from Conyza filaginoides (D. C.) Hieron (Asteraceae), Croton fragilis HBK. (Euphorbiaceae), Dodonaea viscosa Jacq. (Sapindaceae), Gymnosperma glutinosum (Spreng) Less. (Asteraceae), Parthenium tomentosum DC. var. stramonium (Greene) Rollins (Asteraceae), Potentilla thurberi A. Gray (Rosaceae), Pterogonum atrorubens (Englem.) H. Gross (Polygonaceae), Zornia venosa Mohlenbr. (Fabaceae) and Datura lanosa Barclay ex Bye (Solanaceae). In all the cases the extracts inhibited, in a concentration-dependent manner, the spontaneous contraction of the intestinal smooth muscle. The most active extract was that of D. viscosa. These findings tend to support the ethnomedical use of the selected species as spasmolytic agents in Mexican traditional medicine. Additionally, the potential antimicrobial activity of the extracts against pathogenic enterobacteria was investigated. Seven of the nine plants evaluated displayed antibacterial effects.

Molecular biology of resistance to potato virus X in potato.

It has been proposed that plants express resistance to pathogens when the product of a resistance gene interacts with an elicitor molecule produced by the pathogen. Although there is one instance with tobacco mosaic virus (TMV) in which virus resistance is known to act through the same type of mechanism, it is not known whether this model accounts generally for resistance interactions with plant viruses. To address this issue the interactions of resistance genes in potato with potato virus X (PVX) have been analysed at the molecular level. PVX is an RNA virus that is affected by three different types of resistance locus in various potato cultivars. By using recombinant isolates of PVX, incorporating components of strains or mutant viruses able to overcome or avoid the effects of the resistance loci, we have identified different regions of the viral genome that determine the outcome of the resistance interaction. This information has allowed us to investigate the resistance in detail. For example, with the resistance specified by the Rx locus, it has been shown that the coat protein is an avirulence determinant and elicitor of an induced resistance. This resistance acts by reducing virus accumulation in the inoculated cell. Although the recognition component of the resistance is highly specific, the induced response is apparently non-specific and is effective against viruses unrelated to PVX in cells doubly inoculated with PVX and a second virus. The recognition function of Rx is also expressed in Gomphrena globosa which is a non-host plant of PVX. Based on these data, we propose that virus resistance fits the paradigm of resistance to fungal and bacterial pathogens and that there are similarities between the mechanism of cultivar specific resistance and non-host resistance to pathogen attack. Further analysis of the mechanism of the non-specific response phase may ultimately allow genetic engineering of broad-spectrum virus resistance in crop plants.

A feature of the coat protein of potato virus X affects both induced virus resistance in potato and viral fitness.

The coat protein of PVX determines whether isolates of PVX are affected by Rx-mediated resistance in potato. Isolates with the coat protein of PVXHB are not affected by the resistance; those with the coat protein of PVXUK3 elicit an extreme resistance in the Rx potato that prevents virus accumulation, even on the inoculated leaf. In this paper we describe the analysis of a series of hybrid and mutant isolates of PVXHB and PVXCP4 which were inoculated to plants and protoplasts of Rx and rx cultivars of potato. From the virulence phenotypes of these isolates we conclude that elicitation of the resistance is affected by amino acids 121 and 127 of the viral coat protein, with codon 121 being the major determinant. PVXHB and hybrid or mutant isolates with lysine and arginine at positions 121 and 127 were able to overcome the resistance of Rx, whereas those with threonine and arginine were resistance sensitive both on plants and in protoplasts. The viral isolates with single mutations at either codon 121 or 127 were less infectious than the wild-type or double mutant isolates although, in protoplasts of the susceptible cultivar of potato, they accumulated as well as the wild-type virus. Taken together these data suggest that amino acids 121 and 127 affect a feature of the viral coat protein which may interact with cellular components involved in the spread of PVX and with the product of the Rx resistance gene.

Molecular analysis of potato virus X isolates in relation to the potato hypersensitivity gene Nx.

The coat protein gene of potato virus X is known to affect the outcome of interactions between different strains of the virus and potato plants carrying the Nx resistance gene. To analyze the role of the coat protein in interactions with Nx hosts, we used the potato virus X strain PVXDX, which induces a hypersensitive response on potato cultivars carrying the Nx resistance gene and the strain PVXDX4, which was originally derived from PVXDX and which overcomes Nx-mediated resistance. Sequencing of cloned coat protein genes representing the strains PVXDX and PVXDX4 showed that they differed at a single nucleotide. This change results in the substitution of glutamine-78 in the PVXDX coat protein for proline in PVXDX4. We constructed hybrid viral genomes by replacing the coat protein gene of a full-length clone of isolate PVXUK3 with the corresponding sequence from either PVXDX or PVXDX4. Progeny virus, derived from in vitro transcripts of these hybrid clones, showed that the single nucleotide difference between the coat protein genes of isolates PVXDX and PVXDX4 was sufficient to alter the outcome of the interaction between the virus and potato plants carrying the resistance gene Nx. Additional coat protein mutants generated in planta from transcript-derived inocula induced an intermediate host response on Nx potato cultivars which is influenced by the presence of a second, PVX-specific, resistance gene in the host plant genome.

Molecular analysis of a resistance-breaking strain of potato virus X.

Full-length cDNA clones of potato virus X (PVX) strains PVXUK3 and PVXHB have been constructed in plasmid vectors to allow in vitro transcription of infectious PVX RNA. In both instances the transcript-derived virus infected tobacco and potato identically to the respective progenitor strains: in tobacco and susceptible potato cultivars both strains infected systemically, producing symptomless or mild mosaic symptoms. In potato carrying the Rx or Nx resistance genes, the virus derived from the PVXHB cDNA infected systemically, whereas the virus derived from the PVXUK3 cDNA failed to infect the Rx plants or induced apical necrosis, characteristic of a hypersensitive response of the Nx gene. Three hybrid viral genomes were constructed at the cDNA level to localize the resistance breaking determinants of PVXHB. Transcripts of all three hybrids were infectious on tobacco. On potato cultivars with either the Rx or Nx resistance genes, the hybrid viruses infected in the same way as PVXHB, rather than PVXUK3. The common feature of these hybrid viruses, the coat protein gene, is therefore the determinant of Nx and Rx resistance breaking of PVXHB.

Conditioning and recovery of functions lost by brain damage.

The muscle spindle is a receptor apparatus in striated muscle that is necessary for voluntary muscle movement. Paralysis victims lose the feedback of this receptor and cannot initiate motor responses. Four hemiplegic patients were trained to use auditory feedback from electromyographic recordings to initiate activity in paretic limbs. With the addition of visual feedback and the use of the auditory signal as a reinforcing stimulus, the patients' muscle activity was then shaped to approximate normal movement.