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1.
New Phytol ; 192(3): 727-37, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21793829

RESUMEN

• Selenium (Se) hyperaccumulation has a profound effect on plant-arthropod interactions. Here, we investigated floral Se distribution and speciation in flowers and the effects of floral Se on pollen quality and plant-pollinator interactions. • Floral Se distribution and speciation were compared in Stanleya pinnata, an Se hyperaccumulator, and Brassica juncea, a comparable nonhyperaccumulator. Pollen germination was measured from plants grown with varying concentrations of Se and floral visitation was compared between plants with high and low Se. • Stanleya pinnata preferentially allocated Se to flowers, as nontoxic methyl-selenocysteine (MeSeCys). Brassica juncea had higher Se concentrations in leaves than flowers, and a lower fraction of MeSeCys. For B. juncea, high floral Se concentration impaired pollen germination; in S. pinnata Se had no effect on pollen germination. Floral visitors collected from Se-rich S. pinnata contained up to 270 µg g(-1), concentrations toxic to many herbivores. Indeed, floral visitors showed no visitation preference between high- and low-Se plants. Honey from seleniferous areas contained 0.4-1 µg Se g(-1), concentrations that could provide human health benefits. • This study is the first to shed light on the possible evolutionary cost, through decreased pollen germination in B. juncea, of Se accumulation and has implications for the management of seleniferous areas.


Asunto(s)
Brassicaceae/metabolismo , Flores/metabolismo , Polinización/fisiología , Selenio/metabolismo , Animales , Abejas/fisiología , Calcio/metabolismo , Germinación , Humanos , Planta de la Mostaza , Polen/crecimiento & desarrollo , Polen/metabolismo , Azufre/metabolismo
2.
BMC Ecol ; 10: 19, 2010 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-20799959

RESUMEN

BACKGROUND: Hyperaccumulation, the rare capacity of certain plant species to accumulate toxic trace elements to levels several orders of magnitude higher than other species growing on the same site, is thought to be an elemental defense mechanism against herbivores and pathogens. Previous research has shown that selenium (Se) hyperaccumulation protects plants from a variety of herbivores and pathogens. Selenium hyperaccumulating plants sequester Se in discrete locations in the leaf periphery, making them potentially more susceptible to some herbivore feeding modes than others. In this study we investigate the protective function of Se in the Se hyperaccumulators Stanleya pinnata and Astragalus bisulcatus against two cell disrupting herbivores, the western flower thrips (Frankliniella occidentalis) and the two-spotted spider mite (Tetranychus urticae). RESULTS: Astragalus bisulcatus and S. pinnata with high Se concentrations (greater than 650 mg Se kg(-1)) were less subject to thrips herbivory than plants with low Se levels (less than 150 mg Se kg(-1)). Furthermore, in plants containing elevated Se levels, leaves with higher concentrations of Se suffered less herbivory than leaves with less Se. Spider mites also preferred to feed on low-Se A. bisulcatus and S. pinnata plants rather than high-Se plants. Spider mite populations on A. bisulcatus decreased after plants were given a higher concentration of Se. Interestingly, spider mites could colonize A. bisulcatus plants containing up to 200 mg Se kg(-1) dry weight, concentrations which are toxic to many other herbivores. Selenium distribution and speciation studies using micro-focused X-ray fluorescence (µXRF) mapping and Se K-edge X-ray absorption spectroscopy revealed that the spider mites accumulated primarily methylselenocysteine, the relatively non-toxic form of Se that is also the predominant form of Se in hyperaccumulators. CONCLUSIONS: This is the first reported study investigating the protective effect of hyperaccumulated Se against cell-disrupting herbivores. The finding that Se protected the two hyperaccumulator species from both cell disruptors lends further support to the elemental defense hypothesis and increases the number of herbivores and feeding modes against which Se has shown a protective effect. Because western flower thrips and two-spotted spider mites are widespread and economically important herbivores, the results from this study also have potential applications in agriculture or horticulture, and implications for the management of Se-rich crops.


Asunto(s)
Planta del Astrágalo/metabolismo , Brassicaceae/metabolismo , Insectos/fisiología , Selenio/metabolismo , Tetranychidae/fisiología , Animales , Cisteína/análogos & derivados , Cisteína/metabolismo , Cisteína/toxicidad , Preferencias Alimentarias , Compuestos de Organoselenio/metabolismo , Compuestos de Organoselenio/toxicidad , Selenio/toxicidad , Selenocisteína/análogos & derivados
3.
Front Plant Sci ; 6: 113, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25784919

RESUMEN

Selenium (Se)-rich plants may be used to provide dietary Se to humans and livestock, and also to clean up Se-polluted soils or waters. This study focused on endophytic bacteria of plants that hyperaccumulate selenium (Se) to 0.5-1% of dry weight. Terminal restriction fragment length polymorphism (T-RFLP) analysis was used to compare the diversity of endophytic bacteria of hyperaccumulators Stanleya pinnata (Brassicaceae) and Astragalus bisulcatus (Fabaceae) with those from related non-accumulators Physaria bellii (Brassicaceae) and Medicago sativa (Fabaceae) collected on the same, seleniferous site. Hyperaccumulators and non-accumulators showed equal T-RF diversity. Parsimony analysis showed that T-RFs from individuals of the same species were more similar to each other than to those from other species, regardless of plant Se content or spatial proximity. Cultivable endophytes from hyperaccumulators S. pinnata and A. bisulcatus were further identified and characterized. The 66 bacterial morphotypes were shown by MS MALDI-TOF Biotyper analysis and 16S rRNA gene sequencing to include strains of Bacillus, Pseudomonas, Pantoea, Staphylococcus, Paenibacillus, Advenella, Arthrobacter, and Variovorax. Most isolates were highly resistant to selenate and selenite (up to 200 mM) and all could reduce selenite to red elemental Se, reduce nitrite and produce siderophores. Seven isolates were selected for plant inoculation and found to have plant growth promoting properties, both in pure culture and when co-cultivated with crop species Brassica juncea (Brassicaceae) or M. sativa. There were no effects on plant Se accumulation. We conclude that Se hyperaccumulators harbor an endophytic bacterial community in their natural seleniferous habitat that is equally diverse to that of comparable non-accumulators. The hyperaccumulator endophytes are characterized by high Se resistance, capacity to produce elemental Se and plant growth promoting properties.

4.
J Clin Psychiatry ; 62(9): 728-32, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11681770

RESUMEN

BACKGROUND: Use of antipsychotic medication intermittently or over the long term may be necessary in treating patients with bipolar disorder whose symptoms have responded suboptimally to standard mood-stabilizing agents. Quetiapine fumarate is an effective novel antipsychotic with mixed serotonergic (5-HT2) and dopaminergic (D2) activity. This is an open-label, 12-week prospective study to assess the efficacy and tolerability of quetiapine in the treatment of patients with bipolar and schizoaffective disorder who were suboptimally responsive to mood stabilizers alone. METHOD: Participants in the study were inpatients or outpatients with a DSM-IV diagnosis of bipolar or schizoaffective disorder. Baseline psychopathology was evaluated with the Brief Psychiatric Rating Scale (BPRS), the Young Mania Rating Scale (YMRS), and the Hamilton Rating Scale for Depression (HAM-D). Involuntary movements were rated with the Simpson-Angus Neurologic Rating Scale. Quetiapine was added on an open-label basis and increased to optimum clinical dosage. Psychopathology and Abnormal Involuntary Movement Scale ratings were repeated weekly for the first 4 weeks and then again at weeks 8 and 12. RESULTS: Ten individuals with bipolar disorder and 10 with schizoaffective disorder received quetiapine therapy. Overall, patients improved, with significant improvement in BPRS (p < .001), YMRS (p = .043), and HAM-D scores (p = .002). Simpson-Angus score also significantly decreased (p = .02). Overall. quetiapine was well tolerated by patients in this group with serious mood disorders. The mean +/- SD quetiapine dose was 202.9 +/- 124.3 mg/day (range, 50-400 mg/day). Mean weight gain was 10.9 lb (4.9 kg). CONCLUSION: Although limited by its small size, open-label design, and relative gender homogeneity, this study suggests that quetiapine therapy may be useful in the treatment of individuals with serious mood disorders who are suboptimally responsive to mood stabilizers alone. These preliminary findings should be explored in larger, controlled trials.


Asunto(s)
Antipsicóticos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Dibenzotiazepinas/uso terapéutico , Litio/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Ácido Valproico/uso terapéutico , Adulto , Anciano , Antipsicóticos/efectos adversos , Trastorno Bipolar/diagnóstico , Escalas de Valoración Psiquiátrica Breve/estadística & datos numéricos , Dibenzotiazepinas/efectos adversos , Esquema de Medicación , Quimioterapia Combinada , Femenino , Hospitalización , Humanos , Litio/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Trastornos Psicóticos/diagnóstico , Fumarato de Quetiapina , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Ácido Valproico/efectos adversos , Aumento de Peso
5.
Surg Oncol Clin N Am ; 10(1): 71-87, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11406452

RESUMEN

Historically, surgeons have had to witness their patients' pain probably longer than any specialty within medicine. Pain relief in palliative care forms the cornerstone of a comprehensive pattern of care that encompasses the physical, psychologic, social, and spiritual aspects of suffering. In a society that lives by mottoes, such as "no pain, no gain," and "just say no to drugs," pervasive subconscious barriers to effective pain relief exist. In being responsible for effective pain management to the patient, the surgeon must first set aside his or her own beliefs and attitudes regarding pain and its control and be open to change.


Asunto(s)
Cirugía General , Dolor/tratamiento farmacológico , Dolor/prevención & control , Cuidados Paliativos/métodos , Rol del Médico , Cuidado Terminal/métodos , Analgésicos/uso terapéutico , Actitud del Personal de Salud , Actitud Frente a la Muerte , Esquema de Medicación , Humanos , Dolor/diagnóstico , Dolor/etiología , Dimensión del Dolor , Prejuicio , Índice de Severidad de la Enfermedad
6.
Exp Clin Transplant ; 2(2): 238-41, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15859934

RESUMEN

OBJECTIVES: Advances in immunosuppressive therapy have led to substantial improvements in kidney transplant outcomes in the past 20 years. Kidney transplantation activity started in 1963 at the Veterans Administration Medical Center in Nashville, Tennessee, and continues to grow with increasing numbers of transplants from living-related and unrelated donors. In this study, patient and graft survival rates during 2 different periods were evaluated and compared with non-veterans-administration centers. MATERIALS AND METHODS: Six hundred fourteen kidney transplants were performed between March 1963 and December 2002. For analytic purposes, the 40-year experience was divided into 2 eras based on the immunosuppressive agents used. Azathioprine and prednisone were the immunosuppressive agents used in era 1. A calcineurin-inhibitor-based triple immunosuppressive regimen initially including azathioprine and prednisone and later, mycophenolate mofetil and prednisone, was the preferred immunosuppressive regimen in era 2. RESULTS: In era 1, 1-year patient and graft survival rates were 72.5% and 50%, and 89% and 75% for deceased-donor and living-donor transplants respectively. In era 2, patient survival rates increased to 95.1% and 87.8% for 1 and 3 years respectively, while graft survival increased to 87.6% and 74.9%. Forty-three percent of deceased-donor and 21% of living-donor kidneys were lost owing to rejection in era 1. In era 2, the incidence of acute rejection was 14.5% overall. CONCLUSIONS: Overall, our results are comparable with non-veterans-administration centers and the national average and show that kidney transplantation offers veteran patients with end-stage renal disease a safe and effective treatment with increased quality of life.


Asunto(s)
Hospitales de Veteranos , Fallo Renal Crónico/cirugía , Trasplante de Riñón , United States Department of Veterans Affairs , Adulto , Anciano , Cadáver , Femenino , Rechazo de Injerto/epidemiología , Supervivencia de Injerto , Hospitales de Veteranos/estadística & datos numéricos , Humanos , Inmunosupresores/uso terapéutico , Incidencia , Trasplante de Riñón/estadística & datos numéricos , Donadores Vivos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Supervivencia , Estados Unidos , United States Department of Veterans Affairs/estadística & datos numéricos
9.
J Clin Psychol ; 40(4): 1075-7, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6480844

RESUMEN

Shoplifting has become a serious problem for retail merchants and for the criminal justice system. In response to a local court's request for mental health intervention in this problematic area, the Lubbock Regional MHMR Center developed the Shoplifter Offenders Program (SOP), an innovative and novel approach designed to reduce recidivism among convicted adult shoplifters. The principles of Ellis' rational-emotive therapy (RET) served as the conceptual foundation for the intensive, 8-hour psycho-educational group counseling experience (N = 94). Results from the first year of SOP operation are presented, with particular attention paid to the irrational beliefs of shoplifters.


Asunto(s)
Psiquiatría Forense , Psicoterapia Racional-Emotiva/métodos , Psicoterapia/métodos , Disposición en Psicología , Robo , Adulto , Femenino , Humanos , Masculino , Pruebas Psicológicas
10.
DICP ; 24(7-8): 693-5, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1695793

RESUMEN

Quinidine is cited as one of the most frequent causes of drug-induced thrombocytopenia. This case report describes the use of high-dose intravenous gamma globulin to rapidly reverse quinidine-induced thrombocytopenia in a patient at increased risk for bleeding because of the presence of an antitachycardia pacemaker and an automatic implantable cardiac defibrillator. This report suggests that this treatment may aid in a more rapid reversal of quinidine-induced thrombocytopenia in patients at high risk of bleeding.


Asunto(s)
Inmunización Pasiva , Inmunoglobulinas/administración & dosificación , Quinidina/efectos adversos , Trombocitopenia/terapia , Adulto , Humanos , Inyecciones Intravenosas , Masculino , Recuento de Plaquetas , Trombocitopenia/sangre , Trombocitopenia/inducido químicamente , gammaglobulinas/uso terapéutico
11.
Am J Hosp Pharm ; 40(1): 94-7, 1983 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6823997

RESUMEN

The stability and compatibility of droperidol in small-volume i.v. admixtures was assessed. Droperidol was diluted to a nominal concentration of 1 mg/50 ml in 5% dextrose injection, 0.9% sodium chloride injection, and lactated Ringer's injection in type I glass bottles and polyvinyl chloride bags. Triplicate samples of each admixture were stored under continuous illumination at 27 +/- 2 degrees C. Specimens from each sample were tested by spectrophotometric assay at intervals during storage periods of up to 272 hours for admixtures containing 5% dextrose injection and 0.9% sodium chloride injection and up to 168 hours for admixtures containing lactated Ringer's injection. Between 48 and 168 hours of storage, a 7% increase was observed in droperidol concentration in 0.9% sodium chloride admixtures in polyvinyl chloride bags. A 24% decrease in droperidol concentration in lactated Ringer's admixtures in polyvinyl chloride bags between 24 and 168 hours was attributed to sorption of droperidol by the plastic container. In all admixtures except those containing lactated Ringer's injection in polyvinyl chloride bags, droperidol concentrations throughout the storage period were within 10% of initial concentrations. Droperidol is stable in the admixtures studied for 7 to 10 days in glass bottles. In polyvinyl chloride bags, concentrations in admixtures containing 5% dextrose injection and 0.9% sodium chloride injection are stable for seven days, but concentrations decrease significantly in lactated Ringer's admixtures.


Asunto(s)
Droperidol , Combinación de Medicamentos , Composición de Medicamentos , Embalaje de Medicamentos , Estabilidad de Medicamentos , Vidrio , Infusiones Parenterales , Cloruro de Polivinilo
12.
J Clin Psychol ; 39(5): 769-70, 1983 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6630555

RESUMEN

Ninety-four adult first offender shoplifters completed a battery of psychological tests prior to their involvement in a novel and innovative West Texas Shoplifter Offenders Program (SOP). Analysis of the test results indicated that the modal shoplifter is female, Hispanic, and is likely to evidence a subclinical 8-4 high-point pair on the MMPI. Males tend to act more impulsively than females in their shoplifting styles. Shoplifters are no more likely to endorse irrational beliefs than normative groups. However, shoplifters tend to be rather anxious, depressed, and self-doubting. The results are discussed in terms of conceptual implications for SOP design and implementation.


Asunto(s)
MMPI , Robo , Adulto , Consejo/métodos , Femenino , Humanos , Masculino , Psicometría , Autoimagen , Robo/prevención & control
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