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1.
Clin Obes ; 7(2): 92-97, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28146321

RESUMEN

Obesity is associated with lower vitamin D levels compared with normal weight subjects, and if levels are not replaced prior to bariatric surgery, this can increase fracture risk as bone density typically falls post-operatively. We analysed the effect of body mass index (BMI) on vitamin D levels in response to 300 000 IU of colecalciferol in patients with vitamin D deficiency (<30 nmol L-1 ). Patients were grouped according to their BMI as normal weight (20-24.9 kg m-2 ), overweight (25-29.9 kg m-2 ), obese class I (30-34.9 kg m-2 ) and obese class II and above (>35 kg m-2 ). The records were retrospectively analysed to investigate the effects of BMI on vitamin D (total 25-hydroxy vitamin D [25(OH)D]), serum Ca2+ and parathyroid hormone (PTH) levels at 6, 12, 26 and 52 weeks compared with baseline. Compared with normal weight subjects, overweight and obese patients achieved lower mean peak total 25(OH)D levels (6 weeks post-loading), which was most significant in the class II and above group (mean total 25(OH)D levels 96.5 ± 24.2 nmol L-1 and 72.42 ± 24.9 nmol L-1 , respectively; P = 0.003). By 26 weeks, total 25(OH)D levels fell in all groups; however, there was now a significant difference between the normal weight subjects and all other groups (mean total 25(OH)D levels 84.1 ± 23.7 nmol L-1 ; 58 ± 20 nmol L-1 , P = 0.0002; 62.65 ± 19.2 nmol L-1 , P = 0.005; 59.2 ± 21 nmol L-1 , P = 0.005, respectively). Far fewer patients in the overweight and obese groups maintained levels above the recommended level of 75 nmol L-1 52 weeks post-loading (93%; 20%, P = 0.0003; 23%, P = 0.01; and 14%, P = 0.001, respectively). Alternative regimes for the treatment of vitamin D deficiency are needed in overweight and obese patients, especially those in whom bariatric surgery is planned.


Asunto(s)
Índice de Masa Corporal , Ergocalciferoles/administración & dosificación , Obesidad/complicaciones , Deficiencia de Vitamina D/tratamiento farmacológico , Vitaminas/administración & dosificación , Adulto , Anciano , Cirugía Bariátrica , Calcio/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/cirugía , Hormona Paratiroidea/sangre , Periodo Preoperatorio , Estudios Retrospectivos , Factores de Tiempo , Vitamina D/análogos & derivados , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/fisiopatología
2.
Traffic Inj Prev ; 14(1): 13-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23259514

RESUMEN

OVERVIEW: Increasing concerns over the potentially impairing effects of prescriptive sedative drugs such as benzodiazepines on driving have been raised. However, other alternatives such as natural medicines may also carry similar risks with respect to driving safety. Kava (Piper methysticum) is a psychotropic plant commonly used both recreationally and medicinally in the United States, Australia, and the South Pacific to elicit a physically tranquilizing effect. To date no controlled study has tested a medicinal dose of kava versus placebo and a standard sedative drug on driving ability and driving safety. OBJECTIVE: Due to the need to establish the safety of kava in operating a motor vehicle, we compared the acute effects of the plant extract versus the benzodiazepine oxazepam and placebo using a driving simulator. METHODS: A driving simulator (AusEd) was used by 22 adults aged between 18 and 65 years after being randomly administered an acute medicinal dose of kava (180 mg of kavalactones), oxazepam (30 mg), or placebo one week apart in a crossover design trial. RESULTS: No impairing effects on driving outcomes were found after kava administration compared to placebo. Results on specific driving outcome domains revealed that the oxazepam condition had significantly slower braking reaction time compared to the placebo condition (p =.002) and the kava condition (p =.003). The kava condition had significantly fewer lapses of concentration compared to the oxazepam condition (p =.033). No significant differences were found between conditions for steering deviation, speed deviation, and number of crashes. Results were not modified by driving experience. On the Bond-Lader visual analogue sub-scale of alertness, a significant Treatment × Time interaction (p =.032) was found, with a significant reduction over time for oxazepam decreasing alertness (p <.001), whereas no significant reduction was found in the kava or placebo conditions. CONCLUSION: The results indicate that a medicinal dose of kava containing 180 mg of kavalactones does not impair driving ability, whereas 30 mg of oxazepam shows some impairment. Research assessing larger recreational doses of kava on driving ability should now be conducted.


Asunto(s)
Conducción de Automóvil/psicología , Hipnóticos y Sedantes/efectos adversos , Kava/efectos adversos , Extractos Vegetales/efectos adversos , Desempeño Psicomotor/efectos de los fármacos , Adolescente , Adulto , Anciano , Simulación por Computador , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxazepam/efectos adversos , Adulto Joven
3.
J Am Chem Soc ; 130(45): 14970-1, 2008 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-18937460

RESUMEN

The potassium graphite reduction of L:PCl3 leads to the formation of carbene-stabilized diphosphorus molecules, L:P-P:L, 1 (L: = :C{N(2,6-Pri2C6H3)CH}2) and 2 (L: = :C{N(2,4,6-Me3C6H2)CH}2), respectively. The nature of the bonding in 1 and 2 was delineated by DFT computations.


Asunto(s)
Imidazoles/química , Imidazolidinas/química , Metano/análogos & derivados , Fósforo/química , Espectroscopía de Resonancia Magnética , Metano/química , Modelos Moleculares
4.
Science ; 321(5892): 1069-71, 2008 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-18719279

RESUMEN

Dative, or nonoxidative, ligand coordination is common in transition metal complexes; however, this bonding motif is rare in compounds of main group elements in the formal oxidation state of zero. Here, we report that the potassium graphite reduction of the neutral hypervalent silicon-carbene complex L:SiCl4 {where L: is:C[N(2,6-Pri2-C6H3)CH]2 and Pri is isopropyl} produces L:(Cl)Si-Si(Cl):L, a carbene-stabilized bis-silylene, and L:Si=Si:L, a carbene-stabilized diatomic silicon molecule with the Si atoms in the formal oxidation state of zero. The Si-Si bond distance of 2.2294 +/- 0.0011 (standard deviation) angstroms in L:Si=Si:L is consistent with a Si=Si double bond. Complementary computational studies confirm the nature of the bonding in L:(Cl)Si-Si(Cl):L and L:Si=Si:L.

5.
J Am Chem Soc ; 130(3): 901-6, 2008 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-18163618

RESUMEN

Density functional theory studies on a series of Fe2(CO)6(PX)2 derivatives show the tetrahedrane to be the most stable for the alkyl (X = Me, tBu), P-H (X = H), and chloro (X = Cl) derivatives. However, butterfly diradical and planar rhombus structures are found to be more stable than tetrahedranes for the amino (X = NH2, NMe2, and NiPr2) and aryloxy (R = 2,6-tBu2-4-Me-C6H2O) derivatives. For the chloro (X = Cl) and methoxy (X = OMe) derivatives energetically accessible bishomotetrahedrane Fe2(CO)6P2(mu-X)2 isomers are observed in which the X substituents on the phosphorus atoms interact with the iron atom to form two direct Fe-X bonds at the expense of two of the four Fe-P bonds. In addition, the global minimum for the hydroxy (X = OH) derivative is an unusual FeP-butterfly structure with a central Fe-P bond as well as two external Fe-P bonds, one external P-P bond, and one external Fe=Fe double bond. Comparison of calculated with experimental nu(CO) frequencies shows that low-temperature Nujol matrix photolysis of (iPr2NP)2COFe2(CO)6 leads to a planar rhombus rather than a tetrahedrane isomer of Fe2(CO)6(PNiPr2)2.


Asunto(s)
Compuestos de Hierro Carbonilo/química , Fósforo/química , Cristalografía por Rayos X , Isomerismo , Conformación Molecular
6.
Environ Res ; 99(3): 387-96, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16307981

RESUMEN

Coastal marine environments, especially semienclosed systems such as bays, are under unrelenting stress caused by urban and industrial development. Biomonitoring plays a vital role in strategies to identify, assess, and control stressors. However, due to the magnitude of the challenge there is a demand for new and innovative approaches to provide timely and accessible information to environmental managers and policy makers. The present work aimed to assess hydrocarbon levels in sediments from petroleum-related industrial areas at Todos os Santos Bay (Brazil) and associate them to toxicity-induced responses (neutral red retention (NRR) assay) by the burrowing clam Anomalocardia brasiliana. Surface sediments collected during the dry and rainy seasons were analyzed for aliphatic and aromatic hydrocarbons. At the control site, hydrocarbon levels were low and mainly biogenic. The aliphatic hydrocarbon ("total unresolved complex mixture," alkanes, and isoprenoids) concentrations indicated a chronic situation with very little "fresh" oil contamination at the oil-related sites. The polycyclic aromatic hydrocarbons indicated sites moderately contaminated by chronic oil and some pyrolytic input. The effects of those contaminants were assessed by the lysosomal NRR assay applied to A. brasiliana hemocytes. Sediment toxicity at the oil-related sites was evidenced by the lowered capacity of the lysosomes to retain the neutral red dye compared to results from the control site. This research indicates that the NRR assay is a useful and efficient screening technique able to discriminate polluted from clean sites.


Asunto(s)
Bivalvos/fisiología , Hidrocarburos/análisis , Petróleo , Contaminantes Químicos del Agua/análisis , Animales , Bioensayo , Brasil , Ambiente , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Indicadores y Reactivos/análisis , Lisosomas/química , Rojo Neutro/análisis , Estaciones del Año
7.
Med Educ ; 39(6): 580-7, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15910434

RESUMEN

CONTEXT: The ability to perform clinical procedures safely is a key skill for health care professionals. Performing such procedures on conscious patients is challenging and requires a combination of technical and communication skills. We have developed quasi-clinical scenarios, where inanimate models attached to simulated patients provide a convincing learning environment. Procedures are rated by expert observers and by the 'patient' and recorded for subsequent review. This study explores the potential of locating such scenarios within a real clinical setting, allowing participants to experience the challenges of the workplace while ensuring patient safety. An innovative portable digital recording device (the 'Virtual Chaperone') is evaluated for use in clinical settings. METHODS: A qualitative design (observation and interview studies) investigated volunteer medical students undertaking 2 procedure scenarios (insertion of urinary catheter and wound closure with sutures) within the accident unit of a large London hospital. All procedures were observed in real time and recorded digitally (using the Virtual Chaperone). A protocol was used for structured feedback. Observational and interview data was analysed using standard qualitative techniques. RESULTS: Seven sessions with 22 undergraduate medical students took place over 9 months within 1 centre. Data confirmed the feasibility of using a moveable, self-contained training scenario within an authentic clinical setting. Overall, the response from participants was positive. CONCLUSION: Scenario-based teaching within an authentic clinical environment is feasible and perceived by participants to be educationally useful. This approach blurs traditional boundaries between skills laboratory teaching and clinical practice and may offer considerable advantages in training for clinical procedures.


Asunto(s)
Competencia Clínica/normas , Educación de Pregrado en Medicina/métodos , Enseñanza/métodos , Comunicación , Inglaterra , Maniquíes , Desempeño de Papel , Materiales de Enseñanza
8.
Acta Neurochir (Wien) ; 145(12): 1105-10; discussion 1110, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14663568

RESUMEN

BACKGROUND: Safety, feasibility, and efficacy trials in non-human primate stroke models are essential to the evaluation of experimental therapies and their translation to humans. Although Laser Doppler Flowmetry has been successfully employed in rodent stroke to continuously monitor cerebral blood flow, it has not been applied in primate studies. This investigation examined the utility of Laser Doppler Flowmetry in refining an existing baboon model of cerebral ischemia/reperfusion. METHOD: Continuous Laser Doppler Flowmetry monitoring was used, in non-human primates, to document local cerebral blood flow before, during, and after middle cerebral artery territory occlusion. In each baboon (n = 7) a single Doppler probe was placed into the left frontal cortex through a precoronal burr hole. Correlations between Laser Doppler Flowmetry values and latencies to Motor Evoked Potential dropout were compared using a linear regression model. FINDINGS: Placement of the Laser Doppler probe was easily accomplished in all animals. Laser Doppler Flowmetry tracings accurately documented blood flow changes that occurred with each technical manipulation during the procedure. Laser Doppler confirmed decreased perfusion that coincided both regionally and temporally with vessel occlusion. Depth of ischemia as measured by Laser Doppler Flowmetry was associated with Motor Evoked Potential dropout latencies for individual animals. CONCLUSIONS: Continuous, single probe Laser Doppler Flowmetry is a reliable method of documenting perfusion changes following middle cerebral artery territory occlusion in a baboon model of reperfused stroke. This advanced intraoperative monitoring technique may lead to more accurate evaluation of acute stroke therapies in pre-clinical trials.


Asunto(s)
Corteza Cerebral/irrigación sanguínea , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/fisiopatología , Flujometría por Láser-Doppler , Fármacos Neuroprotectores/farmacología , Daño por Reperfusión/fisiopatología , Animales , Dominancia Cerebral/fisiología , Evaluación Preclínica de Medicamentos , Estimulación Eléctrica , Electrodos Implantados , Potenciales Evocados Motores/fisiología , Lóbulo Frontal/irrigación sanguínea , Masculino , Corteza Motora/irrigación sanguínea , Músculo Esquelético/inervación , Papio , Tiempo de Reacción/fisiología
9.
Placenta ; 22(5): 418-24, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11373152

RESUMEN

Phospholipase A2 (PLA2) enzymes that regulate the release of arachidonic acid from cell membrane phospholipids represent a crucial rate-limiting step for the prostaglandin biosynthetic pathway. The aim of this study was to determine the mechanism of action and effects of type II PLA2 antisense oligonucleotides on type II PLA2 mRNA relative abundance, and the release of PLA2 enzymatic activity and prostaglandin F2alpha (PGF2alpha) in vitro. A human placental explant system was used to evaluate the effects of the type II PLA2 specific antisense oligonucleotides A (5'-GGGTGGGTATAGAAGGGCTCC-3', complementary to the base sequence 697-717 of the type II PLA2 gene) and B (5'-TTTTTGATTTGCTAATTGCTT-3', complementary to the base sequence 821-841 of the type II PLA2 gene). PLA2 activity released from explants was quantified by radiolabelled substrate assay using 14C-phosphatidylethanolamine (PE), and PGF2alpha content was analyzed by radioimmunoassay. Compared with control, the release of PLA2 activity and PGF2alpha was significantly reduced over the 24-h period by treatment with both antisense oligonucleotides (P< 0.05). At this concentration, type II PLA2 mRNA abundance was also significantly reduced by both antisense oligonucleotides A and B (P< 0.05). This data demonstrates the efficacy of antisense oligonucleotide inhibition of secretory PLA2 (sPLA2) expression and activity, and the contribution of sPLA2 to placental prostaglandin production.


Asunto(s)
Expresión Génica/efectos de los fármacos , Oligonucleótidos Antisentido/farmacología , Fosfolipasas A/genética , Fosfolipasas A/metabolismo , Northern Blotting , Técnicas de Cultivo , Dinoprost/análisis , Dinoprost/metabolismo , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Fosfatidiletanolaminas/análisis , Fosfatidiletanolaminas/metabolismo , Fosfolipasas A/antagonistas & inhibidores , Fosfolipasas A2 , Placenta/efectos de los fármacos , Placenta/enzimología , Embarazo , ARN Mensajero/análisis
10.
J Manipulative Physiol Ther ; 24(3): 170-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11313612

RESUMEN

OBJECTIVE: To review and identify established methods for evaluating the quality of practice guidelines and to use a selected assessment tool to assess 2 chiropractic practice guideline documents. METHODS: A search of the medical literature was performed to identify current methods and procedures for practice guideline evaluation. Two chiropractic practice guideline documents, Vertebral Subluxation in Chiropractic Practice (CCP) and Guidelines for Chiropractic Quality Assurance and Practice Parameters (Mercy) were then independently evaluated for validity by 10 appraisers using the identified appraisal tool. The appraisal scores were tabulated, and consensus appraisals were generated for the CCP and Mercy guideline documents. RESULTS: The "Appraisal Instrument for Clinical Guidelines" (Cluzeau instrument) was identified as a reliable and valid method of guideline evaluation. The result of the application of this appraisal tool in the assessment of the CCP and Mercy guideline documents was that the former scored notably lower than the latter. On the basis of the results of the guideline appraisals, the CCP document is not recommended, and its guidelines are not considered suitable for application in chiropractic practice. The Mercy guidelines are recommended for application in chiropractic practice, with the proviso that new scientific data should be considered. CONCLUSIONS: The literature reviewed suggests that professional organizations or groups should undertake a critical review of guidelines using available critical guideline appraisal tools. Guideline validity appraisal should be done before acceptance by the chiropractic profession. To avoid unwarranted utilization of poorly constructed guidelines, it is strongly recommended that all future guidelines be reviewed for validity and scientific accuracy with the findings published in a medically indexed journal before they are adopted by the chiropractic community.


Asunto(s)
Quiropráctica , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud , Humanos , Evaluación de Programas y Proyectos de Salud , Reproducibilidad de los Resultados
11.
Am J Clin Oncol ; 24(1): 19-25, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11232944

RESUMEN

Administration of granulocyte colony-stimulating factor to patients undergoing high-dose chemotherapy and autologous peripheral blood stem cell transplantation accelerates neutrophil recovery and decreases hospitalization time. The optimal timing for granulocyte colony-stimulating factor infusion remains unknown. In this retrospective, case-controlled, two-armed study, we reviewed our experience at Hahnemann University Hospital to determine whether initiating granulocyte colony-stimulating factor infusions on posttransplant day 0 versus day 8 affects neutrophil recovery time, posttransplant discharge date, total hospital days after high-dose chemotherapy, and autologous peripheral blood stem cell transplantation. All patients hospitalized between 1994 and 1998 at Hahnemann University Hospital, Bone Marrow Transplantation Unit with breast cancer or non-Hodgkin's lymphoma, who underwent high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation and received granulocyte colony-stimulating factor either on posttransplant day 0 (16 patients) or day 8 (16 patients). The day 0 and day 8 groups had no statistically significant differences in age, sex, weight, height, body surface area, disease characteristics, pretransplant harvesting or conditioning regimens, or transplant CD34+ cell counts. Our main outcome measure was the mean time to reach absolute neutrophil count greater than or equal to 0.5 x 10(9)/l, the number of hospital days after transplant, and the total hospital days. The mean days to neutrophil recovery (10.56 versus 9.68, p = 0.48), posttransplant hospital days (13.62 versus 12.81, p = 0.39), and total hospital days (20.25 versus 20.25, p = 1.00) were not significantly different between day 8 and day 0 groups, respectively. No significant effects on neutrophil recovery time, posttransplant hospital days, or total hospital days were observed with the initial granulocyte colony-stimulating factor infusion on day 0 versus day 8 after transplant. Delayed administration may allow substantial cost savings (US$200 x 8 approximately equal to US $1,600 per patient) without affecting clinical outcome. More studies are needed to determine whether greater delay is feasible.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Trasplante de Células Madre Hematopoyéticas/métodos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/terapia , Estudios de Casos y Controles , Terapia Combinada , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Tiempo de Internación , Recuento de Leucocitos , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/terapia , Masculino , Persona de Mediana Edad , Neutropenia/inducido químicamente , Neutropenia/tratamiento farmacológico , Neutropenia/terapia , Estudios Retrospectivos , Acondicionamiento Pretrasplante/métodos
12.
J Cell Biochem Suppl ; Suppl 37: 7-12, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11842422

RESUMEN

Chemical genetics, in which small molecules are used in lieu of mutations to study biological processes, requires large and diverse chemical libraries to specifically perturb different biological pathways. Here we describe a suite of technologies that enable chemical libraries prepared by split-pool solid phase synthesis to be screened in a diverse range of chemical genetic assays. Compounds are synthesized on 500 micron high-capacity polystyrene beads, and arrayed into individual wells of 384-well plates using a hand-held bead arrayer. Compounds are cleaved from synthesis beads using a chemically-resistant ceramic dispensing system, producing individual stock solutions of single compounds. Nanoliter volumes of these solutions are then transferred into assay plates using an array of stainless steel pins mounted on a robotic arm. We have designed reusable 1536- and 6144-well assay plates made of silicone rubber that can be cast in the laboratory and filled by hand. This integrated technology platform enables hundreds of biological assays to be performed from the product of a single synthesis bead, enabling the results of different chemical genetic experiments to be directly compared.


Asunto(s)
Técnicas Químicas Combinatorias , Genética/tendencias , Proteínas/análisis , Extractos Celulares/química , Evaluación Preclínica de Medicamentos/tendencias , Luciferasas/análisis , Microesferas , Miniaturización , Proteínas/metabolismo
13.
Mol Ecol ; 9(6): 765-70, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10849292

RESUMEN

Diversity in the tRNALEU1 intron of the chloroplast genome of Spartina was used to study hybridization of native California cordgrass, Spartina foliosa, with S. alterniflora, introduced to San Francisco Bay approximately 25 years ago. We sequenced 544 bases of the tRNALEU1 intron and found three polymorphic sites, a pyrimidine transition at site 126 and transversions at sites 382 and 430. Spartina from outside of San Francisco Bay, where hybridization between these species is impossible, gave cpDNA genotypes of the parental species. S. foliosa had a single chloroplast haplotype, CCT, and this was unique to California cordgrass. S. alterniflora from the native range along the Atlantic coast of North America had three chloroplast haplotypes, CAT, TAA, and TAT. Hybrids were discriminated by random amplified polymorphic DNA (RAPD) phenotypes developed in a previous study. We found one hybrid that contained a cpDNA haplotype unknown in either parental species (TCT). The most significant finding was that hybridization proceeds in both directions, assuming maternal inheritance of cpDNA; 26 of the 36 hybrid Spartina plants from San Francisco Bay contained the S. foliosa haplotype, nine contained haplotypes of the invading S. alterniflora, and one had the cpDNA of unknown origin. Furthermore, cpDNA of both parental species was distributed throughout the broad range of RAPD phenotypes, suggesting ongoing contributions to the hybrid swarm from both. The preponderance of S. foliosa cpDNA has entered the hybrid swarm indirectly, we propose, from F1s that backcross to S. foliosa. Flowering of the native precedes by several weeks that of the invading species, with little overlap between the two. Thus, F1 hybrids would be rare and sired by the last S. foliosa pollen upon the first S. alterniflora stigmas. The native species produces little pollen and this has low viability. An intermediate flowering time of hybrids as well as pollen that is more vigourous and abundant than that of the native species would predispose F1s to high fitness in a vast sea of native ovules. Thus, spread of hybrids to other S. foliosa marshes could be an even greater threat to the native species than introductions of alien S. alterniflora.


Asunto(s)
Quimera , Genética de Población , Poaceae/genética , ADN de Plantas/genética , Haplotipos , Polen , Polimorfismo Genético , ARN de Transferencia de Leucina , Técnica del ADN Polimorfo Amplificado Aleatorio , San Francisco , Selección Genética , Análisis de Secuencia de ADN
15.
Chem Biol ; 7(4): 275-86, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10780927

RESUMEN

BACKGROUND: Understanding the molecular mechanisms of complex cellular processes requires unbiased means to identify and to alter conditionally gene products that function in a pathway of interest. Although random mutagenesis and screening (forward genetics) provide a useful means to this end, the complexity of the genome, long generation time and redundancy of gene function have limited their use with mammalian systems. We sought to develop an analogous process using small molecules to modulate conditionally the function of proteins. We hoped to identify simultaneously small molecules that may serve as leads for the development of therapeutically useful agents. RESULTS: We report the results of a high-throughput, phenotype-based screen for identifying cell-permeable small molecules that affect mitosis of mammalian cells. The predominant class of compounds that emerged directly alters the stability of microtubules in the mitotic spindle. Although many of these compounds show the colchicine-like property of destabilizing microtubules, one member shows the taxol-like property of stabilizing microtubules. Another class of compounds alters chromosome segregation by novel mechanisms that do not involve direct interactions with microtubules. CONCLUSIONS: The identification of structurally diverse small molecules that affect the mammalian mitotic machinery from a large library of synthetic compounds illustrates the use of chemical genetics in dissecting an essential cellular pathway. This screen identified five compounds that affect mitosis without directly targeting microtubules. Understanding the mechanism of action of these compounds, along with future screening efforts, promises to help elucidate the molecular mechanisms involved in chromosome segregation during mitosis.


Asunto(s)
Colchicina/farmacología , Mitosis/efectos de los fármacos , Paclitaxel/farmacología , Animales , Línea Celular , Cromosomas/efectos de los fármacos , Colchicina/análogos & derivados , Evaluación Preclínica de Medicamentos/métodos , Humanos , Microscopía Fluorescente , Microtúbulos/efectos de los fármacos , Estructura Molecular , Paclitaxel/análogos & derivados , Huso Acromático/efectos de los fármacos , Tubulina (Proteína)/metabolismo
16.
J Agric Food Chem ; 48(2): 512-4, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10691667

RESUMEN

Thaxtomin A (1) and B (2), the two major phytotoxins associated with the common scab of potato disease, were transformed into C-14 linked beta-glucosides (3) and (4), respectively, when individually incubated with cultures of Bacillus mycoides in oatmeal broth at 26 degrees C. These biotransformation products when assayed on aseptically produced potato minitubers proved to be much less phytotoxic than the parent compounds.


Asunto(s)
Bacillus/metabolismo , Glucósidos/metabolismo , Indoles/metabolismo , Piperazinas/metabolismo , Enfermedades de las Plantas , Solanum tuberosum/metabolismo , Biotransformación , Solanum tuberosum/microbiología , Streptomyces/metabolismo
17.
J Sports Sci ; 17(11): 853-9, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10585165

RESUMEN

We investigated the effect of an acute creatine loading (25 g per day for 4 days) and longer-term creatine supplementation (5 g of creatine or 5 g of placebo per day for 2 months) on the performance of 22 elite swimmers during maximal interval sessions. After the acute creatine loading, the mean of the average interval swim times for all swimmers (n = 22) improved (44.3+/-16.5 s before vs. 43.7+/-16.3 s after supplementation; P<0.01). Three of the 22 swimmers did not respond positively to supplementation. After 2 months of longer-term creatine supplementation or placebo, neither group showed a significant change in swimming performance (38.7+/-13.5 s before vs. 38.7+/-14.1 s after for the creatine group; 48.7+/-18.0 s before vs. 48.7+/-18.1 s after for the placebo group). We conclude that, in elite swimmers, 4 days of acute creatine loading improves swimming performance significantly when assessed by maximal interval sessions. However, longer-term supplementation for 2 months (5 g of creatine per day) did not benefit significantly the creatine group compared with the placebo group.


Asunto(s)
Cardiotónicos/administración & dosificación , Fosfocreatina/administración & dosificación , Resistencia Física/efectos de los fármacos , Natación/fisiología , Adulto , Análisis de Varianza , Suplementos Dietéticos , Esquema de Medicación , Femenino , Humanos , Masculino , Valores de Referencia , Factores de Tiempo
18.
Ultrasound Med Biol ; 25(7): 1087-98, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10574341

RESUMEN

A 256-element, continuous-wave ultrasonic phased array has been used to thermally coagulate deep-seated liver and kidney tissue. The array elements were formed on a 1-3 piezocomposite bowl with a 10-cm radius of curvature and 12-cm diameter. The 0.65 x 0.65 cm2 projection elements were driven at 1.1 MHz by a custom-built amplifier system. A series of in vivo porcine experiments demonstrated the ability to coagulate liver and kidney tissue using the large-scale phased array. The temperature response of the treatment was guided and monitored using magnetic resonance (MR) images. Focal lesion volumes greater than 0.5 cm3 in kidney and 2 cm3 in liver were formed from a single 20-s sonication.


Asunto(s)
Hipertermia Inducida/instrumentación , Neoplasias Renales/terapia , Neoplasias Hepáticas/terapia , Terapia por Ultrasonido/instrumentación , Animales , Diseño de Equipo , Estudios de Factibilidad , Humanos , Riñón/patología , Neoplasias Renales/patología , Hígado/patología , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética/instrumentación , Porcinos
19.
J Altern Complement Med ; 5(6): 553-65, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10630349

RESUMEN

OBJECTIVE: This study was carried out to evaluate the potential effectiveness of herbal treatments used for herpes zoster (HZ) by a great number of people living with acquired immunodeficiency syndrome (PLWAs) in Uganda. SETTING: Kampala, Uganda. Clinics of indigenous traditional healers, at the Department of Medicine of Mulago Hospital, Makerere University, and at The AIDS Support Organization (TASO) Clinic, providing primary care to people living with HIV and AIDS. DESIGN, PATIENTS, AND PARTICIPANTS: Nonrandomized, nonplacebo controlled, observational study in two phases. Inclusion criteria included HIV seropositivity and a recent HZ attack. In phase 1, 52 patients were enrolled, treated, and followed for up to 3 months at three healers' clinics, and compared to 52 TASO Clinic controls receiving ambulatory care. Phase 2 was similar in design to phase 1, but lasted longer (6-month follow-up) and involved 154 hospital outpatients treated with herbal medicine and 55 TASO controls. In both phases, healer patients were given herbal treatment according to healers' prescriptions, while controls received either symptomatic treatment or acyclovir. RESULTS: Healer patients and controls experienced similar rates of resolution of their HZ attacks. Fewer healer patients than controls experienced superinfection in phase 1 (18% versus 42%, p < 0.02) and fewer healer patients showed keloid formation in either phase. This difference was not statistically significant. In both phases, zoster-associated pain resolved substantially faster among healer patients with a higher degree of significance in phase 2 where the progression of pain over time could be seen because of the longer follow-up (phase 1: maximum p value (pmax) < pmax < 0.02 at 1 month, pmax < 0.005 at 2 months, pmax < 0.0001 at 3 months). CONCLUSION: Herbal treatment is an important local and affordable primary care alternative for the management of HZ in HIV-infected patients in Uganda and similar settings.


Asunto(s)
Seropositividad para VIH/complicaciones , Herpes Zóster/terapia , Medicinas Tradicionales Africanas , Fitoterapia , Adolescente , Adulto , Femenino , Herpes Zóster/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del Tratamiento , Uganda
20.
Aust N Z J Psychiatry ; 32(5): 666-72, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9805589

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the perceptions of community staff regarding service process and quality, while a public mental health service integrated acute inpatient and continuing care components. METHODS: The study employed a naturalistic successive measures design in which community mental health staff completed a questionnaire on three occasions during the integration process. RESULTS: Staff perceived overall service quality to improve during the integration process with continuity of care being the area subject to greatest improvement. CONCLUSIONS: The integration of acute inpatient and continuing care services resulted in changes to service process and outcome, which were judged by staff to be beneficial, especially with respect to continuity of patient care.


Asunto(s)
Actitud del Personal de Salud , Prestación Integrada de Atención de Salud/normas , Reestructuración Hospitalaria/normas , Servicios de Salud Mental/normas , Calidad de la Atención de Salud/tendencias , Análisis de Varianza , Manejo de Caso/normas , Manejo de Caso/tendencias , Encuestas de Atención de la Salud , Humanos , Estudios Longitudinales , Trastornos Mentales/diagnóstico , Trastornos Mentales/terapia , Servicios de Salud Mental/organización & administración , Nueva Gales del Sur , Evaluación de Procesos, Atención de Salud , Sector Público
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