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1.
Plant Dis ; 99(12): 1738-1743, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30699502

RESUMEN

Chrysanthemum white rust (CWR), caused by Puccinia horiana, is pathogenic on many Chrysanthemum spp. and close relatives, and infects commercially important florist chrysanthemum cultivars (Chrysanthemum × morifolium) throughout the world. Due to regulations, most research and observations with CWR are done in vitro with symptomatic plants. In contrast, research presented herein is based on microscopic examination of symptomatic and asymptomatic plants collected from natural outbreaks in the field. We observed scattered (not in a linear pattern) telial sori on infected chrysanthemum leaves, stems, and flowers that coalesced at high infection levels. Teliospores were mainly two-celled but occasionally one- or three-celled. Promycelia arose from the apical teliospore cell, the basal cell, or both. The number of basidiospores on promycelia varied from one to four. Germ tubes, arising from P. horiana basidiospores, penetrated the host epidermis directly without appressoria. A mucilaginous exudate formed at the site of attachment and penetration of leaf and stem tissue, as well as on internal cell walls. P. horiana colonization was systemic, with intercellular mycelium and intracellular M-haustoria in both symptomatic and asymptomatic infected host tissue. Hyphal anastomosis was observed within infected plants, suggesting that asexual fusion between different P. horiana pathotypes or genotypes might occur.

2.
Plant Dis ; 99(8): 1070-1077, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30695945

RESUMEN

Verticillium nonalfalfae, causal agent of Verticillium wilt, is being considered as a biocontrol for the highly invasive Ailanthus altissima in Pennsylvania. This soilborne fungus is extremely virulent on Ailanthus and rapidly transmitted from diseased to healthy trees within Ailanthus stands. The rapid transmission of the fungus could be facilitated by root grafts, but neither root graft formation in Ailanthus nor Verticillium transmission by root grafts in trees has been reported. Here, V. nonalfalfae transmission between diseased and healthy Ailanthus trees via intraspecific root grafts and clonal growth is evaluated. Using air-spade excavation, dye translocation, and root graft inoculations, functional root grafts were detected between Ailanthus trees and transmission of V. nonalfalfae across root grafts demonstrated. Inoculation of one Ailanthus parent stem resulted in 187 root sprouts showing Verticillium wilt symptoms 12 months after inoculation. This study revealed that clonal growth and root grafts, normally advantageous growth habits, leave Ailanthus stands vulnerable to widespread V. nonalfalfae infection. This study also broadens the understanding of the Ailanthus-Verticillium pathosystem, growth strategies of invasive Ailanthus, and epidemiology of Verticillium wilt within trees.

3.
Plant Dis ; 99(6): 823-835, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30699540

RESUMEN

The naturally occurring Verticillium nonalfalfae has been proposed as a biocontrol agent against the highly invasive Ailanthus altissima in the eastern United States. We tested 71 nontarget woody species for susceptibility to the potential biocontrol agent. In the field, only devil's walkingstick (17% incidence) and striped maple (3%) acquired infections through natural spread from infected A. altissima (100%). Staghorn sumac (16% incidence) also exhibited wilt in close proximity to diseased Ailanthus, although V. nonalfalfae was never recovered. Stem inoculations, which are highly artificial in that they bypass root defenses and flood the xylem with millions of conidia, induced varying levels of wilt and mortality in 10 nontarget species from which V. nonalfalfae was reisolated, although recovery and crown rebuilding occurred following initial wilt in several species including sassafras and northern catalpa. Thirty-seven of the 71 inoculated species exhibited vascular discoloration, although 23 of these species exhibited no outward symptoms (wilt, dieback) for up to 6 years postinoculation. However, V. nonalfalfae was reisolated from three of the 23 species, indicating a tolerant host response. Our results suggest that V. nonalfalfae is generally host-adapted to A. altissima with 78 of 78 A. altissima seed sources from 26 states and Canada showing susceptibility, and offers support for adoption and dissemination of V. nonalfalfae to combat the highly invasive A. altissima.

4.
Phytopathology ; 104(3): 282-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24134719

RESUMEN

Verticillium wilt, caused by Verticillium nonalfalfae, is currently killing tens of thousands of highly invasive Ailanthus altissima trees within the forests in Pennsylvania, Ohio, and Virginia and is being considered as a biological control agent of Ailanthus. However, little is known about the pathogenicity and virulence of V. nonalfalfae isolates from other hosts on Ailanthus, or the genetic diversity among V. nonalfalfae from confirmed Ailanthus wilt epicenters and from locations and hosts not associated with Ailanthus wilt. Here, we compared the pathogenicity and virulence of several V. nonalfalfae and V. alfalfae isolates, evaluated the efficacy of the virulent V. nonalfalfae isolate VnAa140 as a biocontrol agent of Ailanthus in Pennsylvania, and performed multilocus sequence typing of V. nonalfalfae and V. alfalfae. Inoculations of seven V. nonalfalfae and V. alfalfae isolates from six plant hosts on healthy Ailanthus seedlings revealed that V. nonalfalfae isolates from hosts other than Ailanthus were not pathogenic on Ailanthus. In the field, 100 canopy Ailanthus trees were inoculated across 12 stands with VnAa140 from 2006 to 2009. By 2011, natural spread of the fungus had resulted in the mortality of >14,000 additional canopy Ailanthus trees, 10,000 to 15,000 Ailanthus sprouts, and nearly complete eradication of Ailanthus from several smaller inoculated stands, with the exception of a few scattered vegetative sprouts that persisted in the understory for several years before succumbing. All V. nonalfalfae isolates associated with the lethal wilt of Ailanthus, along with 18 additional isolates from 10 hosts, shared the same multilocus sequence type (MLST), MLST 1, whereas three V. nonalfalfae isolates from kiwifruit shared a second sequence type, MLST 2. All V. alfalfae isolates included in the study shared the same MLST and included the first example of V. alfalfae infecting a non-lucerne host. Our results indicate that V. nonalfalfae is host adapted and highly efficacious against Ailanthus and, thus, is a strong candidate for use as a biocontrol agent.


Asunto(s)
Ailanthus/microbiología , Variación Genética , Enfermedades de las Plantas/microbiología , Verticillium/patogenicidad , Ailanthus/crecimiento & desarrollo , Secuencia de Bases , Agentes de Control Biológico , Especies Introducidas , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , Pennsylvania , Filogenia , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/microbiología , Árboles , Verticillium/genética , Verticillium/aislamiento & purificación , Verticillium/fisiología
5.
Plant Dis ; 97(7): 999, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30722582

RESUMEN

Verticillium wilt of the highly invasive tree-of-heaven [Ailanthus altissima (Mill.) Swingle], caused by Verticillium nonalfalfae Interbitzin et al. (1), formerly classified as V. albo-atrum Reinke and Berthold, has been reported in the United States from two states: Pennsylvania (2) and Virginia (3). Infected A. altissima in both states exhibited similar symptoms of wilt, premature defoliation, terminal dieback, yellow vascular discoloration, and mortality. In June 2012, the second author observed dead and dying A. altissima trees in southern Ohio (Pike County) that exhibited symptoms similar to those on diseased A. altissima trees in Pennsylvania and Virginia. Samples were collected from stems of three symptomatic A. altissima trees and sent to Penn State for morphological and molecular identification. Immediately upon arrival, samples were surface-disinfected and plated onto plum extract agar (PEA), a semi-selective medium for Verticillium spp., amended with neomycin and streptomycin (2). The samples yielded six isolates, two from each of the three symptomatic trees, all of which were putatively identified as V. nonalfalfae based on the presence of verticillate conidiophores and formation of melanized hyphae. DNA was extracted from three isolates and molecular analyses performed using known primers (1) coding for elongation factor 1-alpha (EF), glyceraldehyde-3-phosphate dehydrogenase (GPD), and tryptophan synthase (TS). A BLAST search generated sequences that revealed 100% similarity to V. nonalfalfae for all three protein coding genes among the three Ohio isolates and reference sequences from Ailanthus, including isolates VnAaPA140 (GenBank Accession Nos. KC307764, KC307766, and KC307768) and VnAaVA2 (KC307758, KC307759, and KC307760), as well as isolate PD592 from potato (JN188227, JN188163, and JN188035), thereby confirming taxonomic placement of the Ohio Ailanthus isolates among those recovered from Ailanthus in Pennsylvania and Virginia. Aligned sequences from one representative isolate, VnAaOH1, were deposited into GenBank as accessions KC307761 (EF), KC307762 (GPD), and KC307763 (TS). In August 2012, the pathogenicity of all six isolates was confirmed by root-dipping 10 healthy 3-week-old A. altissima seedlings (seeds collected in University Park, PA) into conidial suspensions of 1 × 107 cfu/ml, wherein all inoculated seedlings wilted and died within 4 and 9 weeks, respectively. V. nonalfalfae was reisolated from all inoculated seedlings; control seedlings inoculated with distilled water remained asymptomatic. Ohio is the third state from which V. nonalfalfae has been reported to be pathogenic on A. altissima. If V. nonalfalfae proves to be widespread, it may represent a natural biocontrol for the invasive A. altissima. Also, since USDA APHIS evaluates and regulates new potential biocontrol agents on a state-by-state basis, it is important to document each state in which V. nonalfalfae is killing A. altissima, so that in-state inoculum can be used for biocontrol efforts, simplifying the regulatory process. References: (1) P. Inderbitzin et al. 2011 PLoS ONE, 6, e28341, 2011. (2) M. J. Schall and D. D. Davis. Plant Dis. 93:747, 2009. (3) A. L. Snyder et al. Plant Dis. 96:837, 2013.

6.
Plant Dis ; 97(6): 837, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30722642

RESUMEN

Ailanthus altissima (Mill.) Swingle, commonly known as tree-of-heaven, is an invasive tree species that has spread throughout the United States since its introduction in 1784 (2). During a survey in July 2009, approximately 1,100 A. altissima trees were observed at two locations in western Virginia (a roadside in Montgomery Co. and a wooded area adjacent to a railroad in Bedford Co.) exhibiting foliar wilt symptoms, defoliation, yellowish vascular discoloration, or death at an incidence of ~77%. Similar symptoms on A. altissima were reported in Roanoke, VA in the early 1930s and after 2005 in Pennsylvania, attributed to a Verticillium sp. (1,2). To identify the causal agent, discolored xylem tissue samples were excised from 10 symptomatic A. altissima trees at both locations, soaked in 1% NaOCl for 2 min, rinsed with sterilized distilled water for 5 min, and placed onto plum extract agar. Cultures were incubated in the dark at 22°C for 7 to 14 days. The resultant colonies (three to four per location) were subcultured and identified putatively as a Verticillium sp. closely related to Verticillium albo-atrum Reinke and Berthold (3), based on melanized, thick-walled, resting mycelia and phialides arranged in verticillate whorls that amassed round, oval-shaped conidia (5.1 ± 1.2 µm × 2.8 ± 0.4 µm, n = 100). Molecular identification of two fungal isolates (one per location) was determined by amplification of the protein coding genes elongation factor 1-alpha (EF), glyceraldehyde-3-phosphate dehydrogenase (GPD), and tryptophan synthase (TS), using PCR primers developed recently for Verticillium (3). A BLAST search on the edited contigs revealed 100% sequence similarity for all three protein coding genes among the two isolates and reference sequences of isolates PD592 (GenBank Accessions JN188227, JN188163, and JN188035 for EF, GPD, and TS, respectively) and VnAaPA140 (KC307764, KC307766, and KC307768 for EF, GPD, and TS, respectively) of the newly-proposed species, V. nonalfalfae (formerly V. albo-atrum). Aligned sequences from one representative isolate, VnAaVA2 (Bedford Co.), were deposited into GenBank as KC307758 (EF), KC307759 (GPD), and KC307760 (TS). To confirm pathogenicity to A. altissima, the two molecularly characterized isolates (one per location) were inoculated into 18 10-week old A. altissima stems that were grown in an environmental chamber at 24°C, 60% RH, and a 12-h photoperiod from seeds collected in Blacksburg, VA. A conidial suspension of each isolate was injected into each stem (0.1 ml of 1 × 108 CFU/ml/stem). All 36 seedlings inoculated with the proposed V. nonalfalfae isolates developed wilting of leaflets within 2 weeks post-inoculation (WPI), defoliation of leaflets by 6 WPI, and were dead by 9 WPI. Eighteen control seedlings were inoculated similarly with distilled water, and remained asymptomatic. Fungi resembling the proposed species V. nonalfalfae were reisolated from all inoculated stems except the control plants, and the species confirmed morphologically as described above. V. nonalfalfae is a recently proposed species that can infect a variety of plant species (3). To our knowledge, this is the first report of this proposed species on A. altissima in Virginia. New state reports of this pathogen on A. altissima are important for regulatory issues associated with using this pathogen as a potential biological control agent. References: (1) G. F. Gravatt and R. B. Clapper. Plant Dis. Rep. 16:96, 1932. (2) M. J. Schall and D. D. Davis. Plant Dis. 93:747, 2009. (3) P. Inderbitzin et al. PLoS ONE, 6, e28341, 2011.

7.
Plant Dis ; 96(9): 1381, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30727198

RESUMEN

Chrysanthemum white rust (CWR) is a quarantine-significant pest in the United States (Title 7, Code of Federal Regulations, Part 319.37-2). The causal agent of CWR, Puccinia horiana Henn., is an autoecious, microcyclic rust that is pathogenic on chrysanthemum species (Chrysanthemum spp.) and close relatives within the family Asteraceae. CWR is indigenous to Japan, where it was first reported in 1895 (4). By the 1960s, CWR was found throughout Europe and later spread to Africa, Oceana, South America, and other parts of Asia. In North America, CWR was reported in Mexico and in the United States (New Jersey and Pennsylvania [1977], Oregon and Washington [1990], and California [1991]). Additional detections of CWR were later reported in 22 Pennsylvania counties (2004, 2006 to 2010) (3). These later Pennsylvania reports stated that eradication was attempted at some sites, but unconfirmed observations suggested that the rust pathogen might overwinter in volunteer plants (3). Since "CWR is known to overwinter in Europe where chrysanthemums overwinter (average minimum temperatures ranging from -10°F to 10°F)" (2), the unconfirmed Pennsylvania observations prompted us to determine if P. horiana can overwinter in Pennsylvania. During October 2010, we identified CWR on perennial mums planted at six outdoor garden locations in University Park, PA. Symptomatic plants were quarantined and eradication attempted. Eradicated sites were routinely surveyed and CWR confirmed in July 2011 on volunteer plants at two of the originally infested sites. An additional outdoor garden site with CWR was observed in State College, PA, during October 2011 and eradication attempted. The three infested sites were surveyed throughout the fall and winter of 2011 to 2012. During February 2012, two asymptomatic volunteer plants arising from root pieces were collected from each of the three sites. Each sample was washed with tap water to remove excess soil, examined morphologically, surface sterilized with 10% bleach, and divided into two subsamples. One subsample from each site was divided into crown and root portions and DNA extracted using a Qiagen DNeasy Plant Mini Kit. Molecular analysis was performed using modifications of published primers ITS 5 and Rust1 (1,4). Puccinia horiana was detected in plant roots from one site and in plant crowns from two sites. The remaining two subsamples from each site were transplanted into sterilized potting soil and placed in a clean controlled environment chamber at 18°C and 85% relative humidity (RH). After 6 weeks, six actively growing plants were transferred to a second clean controlled environment chamber at 17°C and 90 to 100% RH. On 6 April 2012, CWR symptoms and signs were confirmed morphologically on two plants that had been removed from one site. On 19 April 2012, CWR signs and symptoms were confirmed morphologically and by molecular analysis on leaves of volunteer plants at one University Park site. DNA extractions were sequenced and shared a 100% maximum identity to a known P. horiana accession (EU816920.1) in GenBank. To our knowledge, this is the first confirmed report of P. horiana overwintering in Pennsylvania. References: (1) H. Alaei et al. Mycol. Res. 113:668, 2009. (2) Anon. Chrysanthemum White Rust Bulletin, Syngenta Flowers Inc., Gilroy, CA, 2010. (3) S. Kim et al. Phytopathology 101:S91, 2011. (4) K. Pedley. Plant Dis. 93:1252, 2009.

8.
J Exp Med ; 173(3): 743-6, 1991 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-1900083

RESUMEN

During the course of analyzing circular DNA in mouse thymocytes, novel recombinants were identified with immunoglobulin heavy chain joining gene and switch region probes. These circles represent excision products of recombination between the heptamer-nonamer motif for V-(D)-J joining and a repetitive sequence for class switching. The molecular mechanisms that generate "hybrid circles" are discussed.


Asunto(s)
ADN Circular/genética , Genes de Cambio , Cadenas Pesadas de Inmunoglobulina/genética , Región de Unión de la Inmunoglobulina/genética , Región de Cambio de la Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Recombinación Genética , Secuencias Repetitivas de Ácidos Nucleicos , Linfocitos T/inmunología , Animales , Secuencia de Bases , Clonación Molecular , Sondas de ADN , ADN Circular/aislamiento & purificación , Biblioteca de Genes , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Mapeo Restrictivo , Timo/inmunología
9.
Science ; 186(4165): 733-6, 1974 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-17792265

RESUMEN

The gaseouis plume from an isolated 1000-megawatt power plant was systematically examined from a single engine aircraft to determine the extent to which NO(x) and SO(2), chemistry occurs as a function of distance. The concentrations of ambient ozone, water vapor, and hydroxyl free radicals are indicated to be of major importance in defining the chemistry of power plant plumes during summertime conditions.

10.
Science ; 179(4070): 280-2, 1973 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-17802355

RESUMEN

From measurements of the photochemical rate of production of CO(2)(16,18) and CO(2)(16,16), produced from the low intensity photolysis of mixtures of CO, H(2)O, Ar, and O(2)(18,18), the rate constant for the reaction HO(2) + CO --> CO(2) + OH has been determined at 300 degrees K to be less than or equal to 10(-20) cubic centimeter per molecule per second. These measurements indicate that the reaction of thermalized HO(2) is of negligible importance as a sink mechanism for converting CO to CO(2) in either the troposphere or the stratosphere.

11.
Environ Pollut ; 151(1): 79-92, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17524537

RESUMEN

Field studies were conducted during 2003 and 2004 from early June to the end of August, at 20 sites of lower or higher elevation within north-central Pennsylvania, using seedlings of black cherry (Prunus serotina, Ehrh.) and ramets of hybrid poplar (Populus maximowiziixtrichocarpa). A linear model was developed to estimate the influence of local environmental conditions on stomatal conductance. The most significant factors explaining stomatal variance were tree species, air temperature, leaf vapor pressure deficit, elevation, and time of day. Overall, environmental factors explained less than 35% of the variation in stomatal conductance. Ozone did not affect gas exchange rates in either poplar or cherry. Ozone-induced foliar injury was positively correlated with cumulative ozone exposures, expressed as SUM40. Overall, the amount of foliar injury was better correlated to a flux-based approach rather than to an exposure-based approach. More severe foliar injuries were observed on plants growing at higher elevations.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Oxidantes Fotoquímicos/toxicidad , Ozono/metabolismo , Hojas de la Planta/metabolismo , Populus/metabolismo , Prunus/metabolismo , Contaminantes Atmosféricos/metabolismo , Exposición a Riesgos Ambientales , Monitoreo del Ambiente/métodos , Modelos Lineales , Oxidantes Fotoquímicos/metabolismo , Ozono/toxicidad , Pennsylvania , Estaciones del Año , Temperatura
12.
Environ Pollut ; 133(3): 553-67, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15519730

RESUMEN

The crowns of five canopy dominant black cherry (Prunus serotina Ehrh.), five white ash (Fraxinus americana L.), and six red maple (Acer rubrum L.) trees on naturally differing environmental conditions were accessed with scaffold towers within a mixed hardwood forest stand in central Pennsylvania. Ambient ozone concentrations, meteorological parameters, leaf gas exchange and leaf water potential were measured at the sites during the growing seasons of 1998 and 1999. Visible ozone-induced foliar injury was assessed on leaves within the upper and lower crown branches of each tree. Ambient ozone exposures were sufficient to induce typical symptoms on cherry (0-5% total affected leaf area, LAA), whereas foliar injury was not observed on ash or maple. There was a positive correlation between increasing cumulative ozone uptake (U) and increasing percent of LAA for cherry grown under drier site conditions. The lower crown leaves of cherry showed more severe foliar injury than the upper crown leaves. No significant differences in predawn leaf water potential (psi(L)) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (g(wv)) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (P(n)), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P < 0.05). The inconsistent differences in gas exchange response within the same crowns of ash and the uncoupling relationship between g(wv) and P(n) demonstrate the strong influence of heterogeneous environmental conditions within forest canopies.


Asunto(s)
Acer/química , Fraxinus/química , Oxidantes Fotoquímicos/toxicidad , Ozono/toxicidad , Prunus/química , Árboles/química , Acer/fisiología , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Fraxinus/fisiología , Pennsylvania , Fotosíntesis/fisiología , Hojas de la Planta/química , Hojas de la Planta/fisiología , Prunus/fisiología , Estaciones del Año , Suelo , Temperatura , Árboles/fisiología
13.
Biol Psychiatry ; 20(8): 843-51, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4027300

RESUMEN

In an investigation of biological indicators of stress in normal humans, undergraduate psychology students were differentiated on trait anxiety and assessed under baseline, preexam (stress), and postexam conditions. Assessment at each condition involved drawing 20 ml of blood, followed by self-reporting for selected questionnaires. Self-reports included state anxiety, general psychological symptomatology, dysfunctional attitudes, academic confidence, sleep patterns, and intake of drugs, including alcohol and caffeine. Blood was analyzed for whole blood serotonin content, plasma MHPG, and platelet imipramine binding. Baseline differences between high and low trait anxious students on biological measures were significant only for whole blood serotonin content. Variation across situational conditions was significant for whole blood serotonin, with an increase under the stressful condition for both anxiety groups. Thus, serotonin is highlighted as an important factor in the human response to stress, whereas expected differences in MHPG were not observed. The serotonergic response to stress was not explained by changes in psychological or physical state variables. Changes in serotonin content were positively correlated with changes in platelet imipramine binding.


Asunto(s)
Ansiedad/sangre , Plaquetas/metabolismo , Glicoles/sangre , Metoxihidroxifenilglicol/sangre , Serotonina/sangre , Estrés Psicológico/sangre , Adolescente , Adulto , Ansiedad/complicaciones , Evaluación Educacional , Humanos , Imipramina/metabolismo , Estrés Psicológico/complicaciones
14.
Clin Pharmacol Ther ; 32(2): 235-9, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7094511

RESUMEN

We examined the hemodynamic effects of pirmenol, a new antiarrhythmic drug, for the first time in man. Right and left heart pressures, Fick cardiac output, and radionuclide ejection fraction were measured before and during infusion of pirmenol in 10 patients with coronary artery disease who were undergoing routine diagnostic cardiac catheterization. Pirmenol was given as a 50-mg IV injection over 2 min followed by a constant infusion of 2.5 mg/min for up to 36 min. Plasma pirmenol levels were within or near the previously determined therapeutic range in all patients. There were no significant changes in systolic blood pressure or cardiac output. Diastolic blood pressure rose from a mean (+/- SD) 78 +/- 7 during the control period to 82 +/- 6 during the infusion, heart rate rose from 66 +/- 6 during the control period to 75 +/- 7 during infusion and ejection fraction fell from 60 +/- 8 during control to 55 +/- 12 during infusion. Although the left ventricular end-diastolic pressure rose from 6 +/- 2 during control to 8 +/- 3 during the infusion, the left ventricular stroke work index fell and the left ventricular work index per minute did not change. The fall in ejection fraction did not correlate with the control ejection fraction, plasma pirmenol levels, or the change in heart rate. The decline in ejection fraction and the failure of the left ventricular work index per minute to rise despite a small rise in left ventricular end-diastolic pressure may indicate a potential myocardial depressant effect of pirmenol.


Asunto(s)
Antiarrítmicos/farmacología , Hemodinámica/efectos de los fármacos , Piperidinas/farmacología , Evaluación de Medicamentos , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad
15.
Chest ; 119(1): 224-7, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11157608

RESUMEN

BACKGROUND: Long-term mechanical ventilation is considered as a relative or absolute contraindication for lung transplantation by most centers. We report on the results of transplantation in nine patients requiring long-term mechanical ventilation at two lung transplant centers. METHODS: The study group (group 1) consisted of nine patients receiving mechanical ventilation who underwent lung transplantation at either Duke University Medical Center or the University of Florida between 1992 and 1997. Patients in group 1 met the following criteria: they underwent exercise therapy with a physical therapist, and they were without panresistant bacterial airway colonization. The study patients that met these criteria spent at least 13 days receiving mechanical ventilation prior to transplantation. The control population (group 2; n = 65) consisted of all patients who underwent transplantation at either center in the calendar year 1997 who were ventilator independent. The 1-year survival rates in each group were calculated by the Kaplan-Meier method. The number of days required for extubation in each group were compared by the nonparametric Wilcoxon rank sum test. The FEV(1) value at 1 year was reported in each group. RESULTS: The 1-year survival rates were 78% and 83% in group 1 and group 2, respectively. The mean number of days required until extubation were 41 days in group 1 and 9 days in group 2 (p < 0.01). The allograft function was comparable in the two groups at 1 year. CONCLUSIONS: In a select population of ventilator-dependent patients, the 1-year survival rate is comparable to the standard lung transplant population. However, these ventilator-dependent patients require a significantly longer time until extubation than other transplant recipients.


Asunto(s)
Trasplante de Pulmón , Complicaciones Posoperatorias/mortalidad , Respiración Artificial , Adolescente , Adulto , Contraindicaciones , Femenino , Estudios de Seguimiento , Volumen Espiratorio Forzado , Humanos , Tiempo de Internación , Cuidados a Largo Plazo , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Desconexión del Ventilador
16.
Science ; 192(4238): 441-5, 1976 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-17731073
17.
J Consult Clin Psychol ; 61(2): 270-5, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8473580

RESUMEN

Cognitive therapy has emerged as 1 of the most promising psychosocial interventions for the treatment of depression. It appears to be at least the equal of alternative interventions (including pharmacotherapy) with respect to acute treatment. In addition, there are indications that it may reduce risk of symptom return after treatment termination. Nonetheless, design limitations reduce the certainty with which such conclusions can be drawn. Furthermore, tests of its efficacy have largely been limited to nonbipolar outpatient (or subclinical) samples. At this time, cognitive therapy is best considered a promising, but as yet not adequately tested, intervention for the treatment of depression.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Trastorno Depresivo/terapia , Antidepresivos/uso terapéutico , Terapia Combinada , Trastorno Depresivo/psicología , Estudios de Seguimiento , Humanos , Recurrencia
18.
Med Hypotheses ; 21(2): 153-64, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3641029

RESUMEN

It is proposed that humans are capable of a unique type of learning. All other animals are limited to contiguous learning (not more than 60 seconds separating the two events). Only humans are capable of "separated" or scientific learning (learning a connection between two or more events separated by more than 60 seconds). Science itself is a generalized type of non-contiguous learning. It is also proposed that humans' capacity for separated learning is dependent upon the unique ability to hypothesize (to propose a connection or relationship between two or more events separated by time). As a result of separated learning, humans are the only animals capable of "separated foresight" (anticipating which events are likely to occur more than one minute into the future).


Asunto(s)
Aprendizaje , Animales , Cognición/fisiología , Perros , Humanos , Instinto , Inteligencia , Aprendizaje/fisiología , Memoria/fisiología , Ratas , Factores de Tiempo
19.
Addict Behav ; 13(3): 275-83, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3177071

RESUMEN

The neuropsychological and behavioral status of children exposed to narcotics in utero was investigated using the Wechsler Intelligence Scale for Children-Revised, the Bender-Gestalt, the Quick Neurological Screening Test, and the Burks Behavior Rating Scales. The narcotic-exposed children scored significantly lower than control children on Performance and Full-Scale IQs and most of the performance subtests. They scored significantly in the more pathological direction on Hand Skill, Figure Recognition and Reproduction, and Behavioral Irregularities. The narcotic-exposed children were significantly lower on the neurological indicators of the Bender-Gestalt. They scored significantly in the more pathological direction on almost all of the behavioral variables. The children exposed to methadone in utero scored in the more pathological direction than those exposed to heroin so as to raise questions directed toward the societal and ethical implications of methadone treatment.


Asunto(s)
Heroína/efectos adversos , Metadona/efectos adversos , Síndrome de Abstinencia Neonatal/psicología , Pruebas Neuropsicológicas , Trastornos Relacionados con Sustancias/psicología , Adolescente , Niño , Estudios de Seguimiento , Humanos , Recién Nacido , Inteligencia/efectos de los fármacos , Psicometría
20.
Environ Pollut ; 70(3): 241-54, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-15092135

RESUMEN

Field-grown black cherry (Prunus serotina Ehrh.) seedlings were treated with the antioxidant ethylenediurea (EDU) to evaluate height, diameter, and above-ground dry-weight biomass growth response to ambient ozone over four years. Nine blocks with 44 trees/block were used in a randomized complete block design with three foliar spray treatments: (1) 1000 ppm EDU mixed with a surfactant and water; (2) surfactant mixed with water; and (3) water only. In each growing season treatments were applied seven times at approximately 10-day intervals. Repeated measures analysis of variance indicated significant (P< or =0.05) treatment and year effects for log-transformed height and diameter growth over the four-year period. After four years, EDU-treated trees were approximately 17% taller and stem diameters were 21% greater than non-EDU-treated trees. Total above-ground dry-weight biomass at the end of four years was 47% greater for EDU-treated trees compared to non-EDU-treated trees.

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