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1.
Bioresour Technol ; 98(14): 2636-40, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17141500

RESUMO

Eastern redcedar is widespread in the US and produces significant amount of biomass. Open-grown trees invade abandoned fields and compete with valuable forage species in pastures and rangelands. Value-added product development from redcedar is vital for management of eastern redcedar. Cedarwood oil is a valuable component which can be used for further value-added product development. This study examined the effect of age on the distribution of oil in redcedar tree segments. Trunks of eastern redcedar (Juniperus virginiana L.) trees at different stages of growth (26-63 years old) were divided into three sections (top, center and lower). Each section was fractionated separately into bark, heartwood and sapwood segments. Heartwood and sapwood samples from each tree section were analyzed for oil content and composition. A hydrodistillation method was used for oil extraction. Volatile components of tree segments were examined by using a Gas Chromatograph-headspace analysis technique. The heartwood of eastern redcedar contained significantly higher oil than sapwood. Older trees had more oil in the heartwood than younger trees. Both redcedar bark and leaves contained significantly lower oil content than the cedarwood. There were also significant differences in the oil composition of bark, leaves and wood fractions. Cedarwood oil extraction may benefit from prior separation of tree segments prior to oil extraction. However, the economic feasibility of separation prior to an extraction process needs to be further studied. Required extra capital investment and operating costs need to be examined, as well as whether sapwood is worth processing.


Assuntos
Juniperus/metabolismo , Óleos Voláteis/metabolismo , Casca de Planta/metabolismo , Folhas de Planta/metabolismo , Madeira/metabolismo , Juniperus/química , Juniperus/crescimento & desenvolvimento , Óleos Voláteis/química , Madeira/crescimento & desenvolvimento
2.
Epilepsy Res ; 55(1-2): 105-16, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12948620

RESUMO

RATIONALE: In a search for potential supplements or alternatives to the pharmacological treatment of epilepsy, we examined the effects of static magnetic fields on audiogenic seizures of DBA/2 mice. METHODS: Two strains of DBA/2 mice were subjected to auditory stimulation that resulted sequentially in wild running, loss of righting, clonus, tonic hindlimb extension, and death in 80-95% of animals in different experiments. The incidence of seizure stages in groups of animals pretreated with a static magnetic field, phenytoin (PHT) or both was compared to the incidence in sham-exposed control mice. RESULTS: Depending on magnetic flux density and duration of exposure to the field, seizure severity decreased significantly, but not completely, in both strains. However, incidence of five seizure stages was reduced in one strain, with about half of the mice seizure free. Two seizure stages (tonic hindlimb extension and death) were reduced significantly in the other. Magnetic field pretreatment potentiated the effect of PHT. Clonic seizures refractory to PHT or magnetic field pretreatment in DBA/2J mice responded to pretreatment with a combination of PHT and the magnetic field. CONCLUSIONS: A static magnetic field had some anticonvulsant effects when employed alone. More robust effects were seen in combination with PHT. Further testing of magnetic fields for anticonvulsant effects and elucidation of mechanisms of action seem to be warranted.


Assuntos
Anticonvulsivantes/uso terapêutico , Campos Eletromagnéticos , Epilepsia Reflexa/fisiopatologia , Epilepsia Reflexa/terapia , Fenitoína/uso terapêutico , Estimulação Acústica/efeitos adversos , Animais , Relação Dose-Resposta a Droga , Epilepsia Reflexa/tratamento farmacológico , Feminino , Masculino , Camundongos , Camundongos Endogâmicos DBA , Especificidade da Espécie , Eletricidade Estática
3.
Arch Phys Med Rehabil ; 82(10): 1453-60, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11588753

RESUMO

OBJECTIVE: To assess the efficacy of a nonpharmacologic, noninvasive static magnetic device as adjunctive therapy for knee pain in patients with rheumatoid arthritis (RA). DESIGN: Randomized, double-blind, controlled, multisite clinical trial. SETTING: An American and a Japanese academic medical center as well as 4 community rheumatology and orthopedics practices. PATIENTS: Cohort of 64 patients over age 18 years with rheumatoid arthritis and persistent knee pain, rated greater than 40/100mm, despite appropriate use of medications. INTERVENTION: Four blinded MagnaBloc (with 4 steep field gradients) or control devices (with 1 steep field gradient) were taped to a knee of each subject for 1 week. MAIN OUTCOME MEASURES: The American College of Rheumatology recommended core set of disease activity measures for RA clinical trials and subjects' assessment of treatment outcome. RESULTS: Subjects randomly assigned to the MagnaBloc (n = 38) and control treatment groups (n = 26) reported baseline pain levels of 63/100mm and 61/100mm, respectively. A greater reduction in reported pain in the MagnaBloc group was sustained through the 1-week follow-up (40.4% vs 25.9%) and corroborated by twice daily pain diary results (p < .0001 for each vs baseline). However, comparison between the 2 groups demonstrated a statistically insignificant difference (p < .23). Subjects in the MagnaBloc group reported an average decrease in their global assessment of disease activity of 33% over 1 week, as compared with a 2% decline in the control group (p < .01). After 1 week, 68% of the MagnaBloc treatment group reported feeling better or much better, compared with 27% of the control group, and 29% and 65%, respectively, reported feeling the same as before treatment (p < .01). CONCLUSIONS: Both devices demonstrated statistically significant pain reduction in comparison to baseline, with concordance across multiple indices. However, a significant difference was not observed between the 2 treatment groups (p < .23). In future studies, the MagnaBloc treatment should be compared with a nonmagnetic placebo treatment to characterize further its therapeutic potential for treating RA. This study did elucidate methods for conducting clinical trials with magnetic devices.


Assuntos
Artralgia/etiologia , Artralgia/terapia , Artrite Reumatoide/complicações , Campos Eletromagnéticos , Articulação do Joelho , Magnetismo/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Pediatr Neurol ; 23(3): 261-4, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11033291

RESUMO

Two adolescents with debilitating, medication-resistant, chronic pain of the low back and abdomen with intermittent pain of the genitalia were diagnosed with intervertebral disk disease at spinal cord levels that correlated with their signs. Both patients had undergone multiple evaluations by physicians of different specialties and both underwent appendectomy without relief of their pain. The history of the onset of pain was important in determining the affected levels. The pain of both individuals was mimicked and localized by percussion of the vertebral spines at the level of disk protrusion. This maneuver and careful review of the history were important in making the correct diagnosis in each case. In both patients, treatment with novel magnetic devices provided rapid relief that was sustained for more than 2 years. These cases highlight the need for careful evaluation and correct diagnosis of abdominal and genital pain in young patients to avoid costly and unnecessary medical intervention and the stigma of painful debility.


Assuntos
Dor Abdominal/terapia , Campos Eletromagnéticos , Dor Lombar/terapia , Testículo , Vulva , Dor Abdominal/etiologia , Adolescente , Doença Crônica , Diagnóstico Diferencial , Feminino , Humanos , Dor Lombar/etiologia , Imageamento por Ressonância Magnética , Masculino , Radiculopatia/diagnóstico , Radiculopatia/terapia , Testículo/inervação , Resultado do Tratamento , Vulva/inervação
5.
Artigo em Inglês | MEDLINE | ID: mdl-10738929

RESUMO

In this study we aimed to assess the reproducibility of the 7-day voiding diary in women with stress urinary incontinence. We compared two 7-day voiding diaries completed at 4-week intervals by 138 women with stress urinary incontinence enrolled in an interventional trial. The correlation coefficient for the number of weekly incontinence episodes between the two diaries was 0.831. For 280 voiding diaries the results of the first 3 days correlated well with results of the last 4 days (r = 0.887). The number of incontinence episodes, as recorded on a 7-day voiding diary, is a reproducible outcome measure in women with stress urinary incontinence. Results from the first 3 days of a diary correlate well with the last 4 days, suggesting that a 3-day diary is an appropriate outcome measure for clinical trials evaluating treatments for stress incontinence.


Assuntos
Registros , Transtornos Urinários/fisiopatologia , Micção , Adulto , Idoso , Ritmo Circadiano , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Tempo , Incontinência Urinária por Estresse/fisiopatologia
6.
Pediatr Pulmonol ; 28(4): 301-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10497380

RESUMO

Congenital pulmonary venous stenosis (CPVS) has been previously described in older infants and children, typically manifesting as failure to thrive with congestive heart failure and subsequent respiratory deterioration. We report on 2 cases of CPVS which presented during the immediate newborn period as severe persistent pulmonary hypertension of the newborn.


Assuntos
Cardiopatias Congênitas/diagnóstico , Síndrome da Persistência do Padrão de Circulação Fetal/diagnóstico , Veias Pulmonares/anormalidades , Angiografia , Cateterismo Cardíaco , Constrição Patológica/congênito , Constrição Patológica/diagnóstico , Diagnóstico Diferencial , Evolução Fatal , Feminino , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/terapia , Humanos , Recém-Nascido , Masculino , Síndrome da Persistência do Padrão de Circulação Fetal/fisiopatologia , Síndrome da Persistência do Padrão de Circulação Fetal/terapia , Respiração Artificial
7.
Biol Neonate ; 75(5): 310-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10095145

RESUMO

Previous measurements of fetal hepatic blood flow have relied on microsphere methodology. Estimates of fetal hepatic oxygen consumption (VO2), based on these measurements and the oxygen content difference across the fetal hepatic circulation, have been quite variable. To estimate hepatic VO2 in the fetal lamb by a different methodology, we applied the Fick principle using the steady-state uptake of indocyanine green (ICG) by the fetal liver to measure left hepatic blood flow in 10 pregnant ewes. Sampling catheters were inserted into the fetal external iliac artery, left hepatic vein, and umbilical vein. ICG was infused to steady state (for approximately 60 min) through a fetal brachial vein. Four sets of ICG concentration differences across the circulation of the left hepatic lobe were determined for each animal, and left hepatic lobe blood flow calculated. The oxygen concentration difference was measured simultaneously and VO2 of the left hepatic lobe calculated. In addition, we measured fetal VO2 and calculated the ratio of hepatic to fetal VO2. Left hepatic lobe blood flow was 382.30 ml/min/100 g tissue (COV = 0.32), a result statistically no different than in 4 animals with an independent measurement of hepatic blood flow using an ethanol equilibration method. Hepatic VO2 was 1.74 micromol/min/g tissue (COV = 0.13), and hepatic to fetal VO2 ratio was 18.23% (COV = 0.19). Our results indicate that normal fetal hepatic oxygen uptake per gram of tissue is less variable than previously suggested, and that ICG can be applied in the fetus for the purpose of hepatic blood flow measurement.


Assuntos
Fígado/embriologia , Fígado/metabolismo , Consumo de Oxigênio , Ovinos/embriologia , Animais , Velocidade do Fluxo Sanguíneo , Corantes/metabolismo , Feminino , Idade Gestacional , Verde de Indocianina/metabolismo , Fígado/irrigação sanguínea , Oxigênio/sangue , Gravidez
10.
J Urol ; 156(6): 1947-50, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8911362

RESUMO

PURPOSE: The computer generated recordings for 2 nights in 40 patients studied with the RigiScan device were reevaluated using the new RigiScan Plus software to test its value in improving the discrimination between psychogenic and organic erectile dysfunction. MATERIALS AND METHODS: Each man was evaluated for erectile dysfunction with a detailed medical and sexual history, physical examination, biothesiometry, plethysmography, 2 nights of ambulatory RigiScan monitoring and a psychological evaluation that usually included a private interview with the sexual partner. At the conclusion of evaluation each patient was broadly classified as having organic or psychogenic erectile dysfunction. The RigiScan reports were initially independently analyzed without the investigator's knowledge of the final diagnosis by determining the single best erectile event, with a minimal cutoff value of 60% erection for 5 minutes as necessary to be considered normal and the sum of measurements from the 2 nights. The original reading and final diagnosis were correlated. At this point the data were processed with the new RigiScan Plus software using 2 new measurements: 1) rigidity activity units and 2) tumescence activity units at the base and tip of the penis, and the results were correlated with the final diagnosis. RESULTS: Evaluation of the single best event again showed that tip rigidity was the best single predictor if the diagnostic criteria were modified to 70% tip rigidity for 5 minutes with an estimate of correct classification of 92.5%. Nearly the same accuracy was obtained by base single event rigidity, tip rigidity and base tumescence activity units (each 90%). The summary analysis of all erectile events during the 2 nights of evaluation that had a low correlation with the final diagnosis using the original software showed that the best overall predictor of final diagnosis was tip tumescence activity units (92.5%), followed by base rigidity and tumescence activity units (each 90%). CONCLUSIONS: The RigiScan Plus software introduced 4 new parameters that facilitate interpretation of the RigiScan data. The new software did not improve the correlation with the final diagnosis compared to the subjective single best event analysis but added new objective parameters, measured and displayed by the software, that facilitate use of the data by the physician.


Assuntos
Disfunção Erétil/diagnóstico , Software , Diagnóstico Diferencial , Humanos , Masculino , Valor Preditivo dos Testes , Análise de Regressão , Urologia/instrumentação
11.
J Urol ; 155(5): 1613-6, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8627835

RESUMO

PURPOSE: Information was collected during the first 2 years of an ongoing, prospective, multi-institutional evaluation of the Dura-II penile prosthesis. Evaluation included data on clinical outcomes and a patient satisfaction survey, and will continue for 5 years after implantation for each patient. MATERIALS AND METHODS: To date 196 patients have been evaluated. Surgical data, adverse events and information from satisfaction surveys are reported. RESULTS: At a followup of 13.4 +/- 8.4 months postoperatively, adverse events occurred in 8.2% of the patients, resulting in reoperation in 5.1%. There have been no mechanical failures. Overall satisfaction rates were 85% at 3 months, 83% at 1 year and 91% at 2 years after implantation, and levels of sexual functioning were correspondingly high. A majority of patients assigned high scores to rigidity, concealability, ability to have intercourse and erection size, although satisfaction with erection size ranked lower than the other measures. CONCLUSIONS: The Dura-II penile prosthesis provides a satisfactory result and has an acceptable level of complications associated with its use. Further followup will assess temporal changes in satisfaction rates and sexual functioning for these patients.


Assuntos
Disfunção Erétil/cirurgia , Prótese de Pênis , Adulto , Idoso , Idoso de 80 Anos ou mais , Disfunção Erétil/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Desenho de Prótese , Resultado do Tratamento
12.
Bioelectromagnetics ; 16(3): 197-206, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7677796

RESUMO

To characterize the properties of static magnetic fields on firing of action potentials (AP) by sensory neurons in cell culture, we developed a mathematical formalism based on the expression for the magnetic field of a single circular current loop. The calculated fields fit closely the field measurements taken with a Hall effect gaussmeter. The biological effect induced by different arrays of permanent magnets depended principally on the spatial variation of the fields, quantified by the value of the gradient of the field magnitude. Magnetic arrays of different sizes (macroarray: four center-charged neodymium magnets of approximately 14 mm diameter; microarray; four micromagnets of the same material but of approximately 0.4 mm diameter) allowed comparison of fields with similar gradients but different intensities at the cell position. These two arrays had a common gradient value of approximately 1 mT/mm and blocked > 70% of AP. Alternatively, cells placed in a field strength of approximately 0.2 mT and a gradient of approximately 0.02 mT/mm produced by the macroarray resulted in no significant reduction of firing; a microarray field of the same strength but with a higher gradient of approximately 1.5 mT/mm caused approximately 80% AP blockade. The experimental threshold gradient and the calculated threshold field intensity for blockade of action potentials by these arrays were estimated to be approximately 0.02 mT/mm and approximately 0.02 mT, respectively, In conclusion, these findings suggest that spatial variation of the magnetic field is the principal cause of AP blockade in dorsal root ganglia in vitro.


Assuntos
Potenciais de Ação/efeitos da radiação , Magnetismo , Neurônios Aferentes/fisiologia , Animais , Células Cultivadas , Simulação por Computador , Relação Dose-Resposta à Radiação , Gânglios Espinais/fisiologia , Neodímio , Neurônios Aferentes/efeitos da radiação
13.
Biopolymers ; 37(1): 29-53, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7880965

RESUMO

The desire to replace the amide backbone of renin inhibitors with a new scaffold led us to explore vinylogous amides (enaminones). An initial attempt proved unsuccessful, a result explained after the fact via docking experiments. Based on this lesson, we designed a different vinylogous amide scaffold which incorporated one or more pyrrolinone rings into the backbone. Three of the four compounds gave IC50S in the 0.6 to 18 microM range. These compounds did not inhibit HIV-1 protease. Taken together, the results reported herein provide insights into the role of hydrogen bonding and steric interactions for binding to renin.


Assuntos
Peptídeos/síntese química , Renina/antagonistas & inibidores , Desenho de Fármacos , Ligação de Hidrogênio , Conformação Proteica
14.
Bioelectromagnetics ; 16(1): 20-32, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7748200

RESUMO

To characterize the inhibitory effect of a static magnetic field, action potentials (AP) were elicited by intracellular application of 1 ms depolarizing current pulses of constant amplitude to the somata of adult mouse dorsal root ganglion neurons in monolayer dissociated cell culture. During the control period, < 5% of stimuli failed to elicit AP. During exposure to an approximately 11 mT static magnetic field at the cell position produced by an array of four permanent center-charged neodymium magnets of alternating polarity (MAG-4A), 66% of stimuli failed to elicit AP. The number of failures was maximal after about 200-250 s in the field and returned gradually to baseline over 400-600 s. A direct or indirect effect on the conformation of AP generating sodium channels could account for these results because 1) failure was preceded often by reduction of maximal rate of rise, an indirect measure of sodium current; 2) recovery was significantly prolonged in more than one-half of neurons that were not stimulated during exposure to the MAG-4A field; and 3) resting membrane potential, input resistance, and chronaxie were unaffected by the field. The effect was diminished or prevented by moving the MAG-4A array along the X or Z axis away from the neuron under study and by increasing the distance between magnets in the XY plane. Reduction of AP firing during exposure to the approximately 0.1 mT field produced by a MAG-4A array of micromagnets was about the same as that produced by a MAG-4A array of the large magnets above. The approximately 28 mT field produced at cell position by two magnets of alternating polarity and the approximately 88 mT field produced by a single magnet had no significant effect on AP firing. These findings suggest that field strength alone cannot account for AP blockade.


Assuntos
Potenciais de Ação/fisiologia , Magnetismo/efeitos adversos , Neurônios Aferentes/fisiologia , Animais , Células Cultivadas , Canais de Cloreto/fisiologia , Cronaxia/fisiologia , Impedância Elétrica , Estimulação Elétrica , Gânglios Espinais/fisiologia , Potenciais da Membrana/fisiologia , Camundongos , Neodímio , Fibras Nervosas/fisiologia , Fibras Nervosas Mielinizadas/fisiologia , Condução Nervosa , Inibição Neural , Canais de Sódio/fisiologia
15.
Science ; 264(5155): 46-7, 1994 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-17778132
16.
J Pediatr Orthop ; 6(2): 150-6, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3958167

RESUMO

An experimental study was conducted to determine the feasibility of using percutaneous drilling and pneumatic burring under image intensification to effect premature closure of the distal femoral epiphyseal plate in immature New Zealand white rabbits. Serial roentgenograms were made before the animals were killed at 6 or 10 weeks to document leg length inequality as compared with the contralateral leg following the procedure. Microscopic examination of nonoperated and operated epiphyseal plate revealed complete arrest of the operated epiphysis with bone fusion at the epiphyseal plate in eight of the nine rabbits. Since this animal study, 13 children have undergone percutaneous epiphysiodesis. Roentgenographically, all the growth plates appeared fused following the procedure. However, complete growth arrest cannot be substantiated until skeletal maturity. This is a preliminary report of a procedure that needs further documentation.


Assuntos
Fêmur/cirurgia , Lâmina de Crescimento/cirurgia , Desigualdade de Membros Inferiores/cirurgia , Osteotomia/métodos , Tíbia/cirurgia , Adolescente , Animais , Criança , Feminino , Humanos , Masculino , Coelhos
17.
Science ; 221(4618): 1394-7, 1983 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-17759014

RESUMO

An explosive eruption of Mount St. Helens on 19 March 1982 had substantial impact beyond the vent because hot eruption products interacted with a thick snowpack. A blast of hot pumice, dome rocks, and gas dislodged crater-wall snow that avalanched through the crater and down the north flank. Snow in the crater swiftly melted to form a transient lake, from which a destructive flood and lahar swept down the north flank and the North Fork Toutle River.

18.
Science ; 220(4599): 848, 1983 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-17834192
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