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1.
Nat Prod Lett ; 15(1): 35-42, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11547421

RESUMEN

A new phenolic glucoside gallate, vanillic acid 4-O-beta-D-(6'-O-galloyl) glucopyranoside (1) was isolated from the bark of Terminalia macroptera Guill.et Perr., together with 3,3',4'-tri-O-methylellagic acid (2) and two triterpene glucopyranosyl esters, 24-deoxysericoside (3) and chebuloside II (4). Compounds 2-4, not described previously for this plant, showed antimicrobial activities against Bacillus subtilis, while 3 and 4 possessed haemolytic properties. In both assays 1 was found to be inactive.


Asunto(s)
Taninos Hidrolizables , Rosales/química , Taninos/aislamiento & purificación , Ácido Vanílico , Bacillus subtilis/efectos de los fármacos , Hemólisis/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Análisis Espectral , Taninos/química , Taninos/farmacología
2.
Phytochemistry ; 57(2): 267-72, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11382243

RESUMEN

The extract of the floral parts of Viguiera quinqueremis afforded, in addition to known compounds, six new sesquiterpene lactones as well as a new myoinositol derivative. All compounds were detected in glandular trichomes which were collected micromechanically from the anther appendages and were analyzed by HPLC. Structure identification was performed by 1H NMR measurements including LC NMR and LC MS experiments.


Asunto(s)
Asteraceae/química , Inositol/aislamiento & purificación , Lactonas/aislamiento & purificación , Sesquiterpenos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Inositol/química , Lactonas/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Sesquiterpenos/química , Termodinámica
3.
J Nat Prod ; 64(3): 294-9, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11277742

RESUMEN

Two new hydrolyzable tannins, isoterchebulin (1) and 4,6-O-isoterchebuloyl-D-glucose (2), together with six known tannins, 3-8, were isolated from the bark of Terminalia macroptera. Their structures were elucidated by extensive 1D and 2D NMR studies, MS, and chemical transformations. Biological activities of all compounds were evaluated against the snail Biomphalaria glabrata, the bacteria Bacillus subtilis and Pseudomonas fluorescens, the nematode Caenorhabditis elegans, and four cancer cell lines (Hep G2, MCF-7/S, MDA-MB-231, and 5637 cells). All compounds except 3 showed antimicrobial activities against B. subtilis (MIC 8-64 microg/mL), whereas only 1 was active against C. elegans (100 microg/mL) and B. glabrata(LC(100) = 60 microg/mL). 3 and 8 were toxic against 5637 cells with LC(50) = 84.66 and 41.40 microM, respectively.


Asunto(s)
Glucosa/aislamiento & purificación , Taninos Hidrolizables , Plantas Medicinales/química , Taninos/aislamiento & purificación , Árboles/química , África , Animales , Antihelmínticos/química , Antihelmínticos/aislamiento & purificación , Antihelmínticos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Bacillus subtilis/efectos de los fármacos , Biomphalaria/efectos de los fármacos , Caenorhabditis elegans/efectos de los fármacos , Glucosa/análogos & derivados , Glucosa/química , Glucosa/farmacología , Espectroscopía de Resonancia Magnética , Moluscocidas/química , Moluscocidas/aislamiento & purificación , Moluscocidas/farmacología , Pseudomonas fluorescens/efectos de los fármacos , Taninos/química , Taninos/farmacología , Tilapia
4.
Planta Med ; 67(1): 65-9, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11270725

RESUMEN

The crude dichloromethane bark extract of Salacia petenensis (Hippocrateaceae) from Monteverde, Costa Rica, shows antibacterial and cytotoxic activity. Bioactivity-directed separation led to the isolation of tingenone and netzahualcoyonol as the biologically active materials. Also isolated from the extract were 3-methoxyfriedel-2-en-1-one (a new natural product) and 29-hydroxyfriedelan-3-one. The structures of these compounds were elucidated on the basis of NMR spectral analysis. Molecular orbital calculations have been carried out using the semi-empirical PM3 and Hartee-Fock 3-21G ab initio techniques on the quinone-methide nortriterpenoids tingenone and netzahualcoyonol, as well as on the nucleotide bases adenine, guanine, cytosine, and thymine. The molecular orbital calculations suggest that a possible mode of cytotoxic action of quinone-methide triterpenoids involves quasi-intercalative interaction of the compounds with DNA followed by nucleophilic addition of the DNA base to carbon-6 of the triterpenoid.


Asunto(s)
Indolquinonas , Indoles/aislamiento & purificación , Quinonas/aislamiento & purificación , Rosales/química , Triterpenos/aislamiento & purificación , Indoles/química , Modelos Moleculares , Estructura Molecular , Quinonas/química , Triterpenos/química
6.
Phytochemistry ; 55(3): 255-61, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11142852

RESUMEN

Extracts of the aerial parts of Viguiera eriophora ssp. eriophora and Viguiera puruana afforded, in addition to known compounds, six new heliangolides and a germacrolide, whose structures were determined by spectral analysis. HPLC analysis and LC NMR experiments revealed the natural occurrence of the compounds in glandular trichomes. The taxonomic relevance of the results is briefly discussed.


Asunto(s)
Asteraceae/química , Lactonas/aislamiento & purificación , Sesquiterpenos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Lactonas/química , Espectroscopía de Resonancia Magnética , Extractos Vegetales/química , Sesquiterpenos/química
7.
Brain Res ; 824(2): 296-9, 1999 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-10196462

RESUMEN

The development of thermal allodynia in relationship to sodium channel augmentation in dorsal root ganglia (DRGs) was studied in albino rats. Paw withdrawal latencies were measured hourly following complete Freund's adjuvant (CFA) injections. Sodium channels were demonstrated with immunocytochemistry. Sustained minimum latencies were attained between 10 and 12 h post-injection. Sodium channel labeling began to increase at 23 h post-injection and reached maximum levels by 24 h. Thermal hypersensitivity is thus established 12 h before sodium channel augmentation can be demonstrated.


Asunto(s)
Ganglios Espinales/fisiopatología , Hipersensibilidad/fisiopatología , Neuritis/fisiopatología , Canales de Sodio/fisiología , Animales , Progresión de la Enfermedad , Calor , Inmunohistoquímica , Umbral del Dolor , Ratas , Ratas Sprague-Dawley , Tiempo de Reacción/fisiología
8.
Chest ; 112(2): 416-22, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9266877

RESUMEN

OBJECTIVE: To compare the probability of cancer in a solitary pulmonary nodule using standard criteria with Bayesian analysis and result of 2-[F-18] fluoro-2-deoxy-D-glucose-positron emission tomographic (FDG-PET) scan. SETTING: A university hospital and a teaching Veteran Affairs Medical Center. METHODS: Retrospective analysis of 52 patients who had undergone both CT scan of the chest and a FDG-PET scan for evaluation of a solitary pulmonary nodule. FDG-PET scan was classified as abnormal or normal. Utilizing Bayesian analysis, the probability of cancer using "standard criteria" available in the literature, based on patient's age, history of previous malignancy, smoking history, size and edge of nodule, and presence or absence of calcification were calculated and compared to the probability of cancer based on an abnormal or normal FDG-PET scan. Histologic study of the nodules was the gold standard. RESULTS: The likelihood ratios for malignancy in a solitary pulmonary nodule with an abnormal FDG-PET scan was 7.11 (95% confidence interval [CI], 6.36 to 7.96), suggesting a high probability for malignancy, and 0.06 (95% CI, 0.05 to 0.07) when the PET scan was normal, suggesting a high probability for benign nodule. FDG-PET scan as a single test alone was more accurate than the standard criteria and standard criteria plus PET scan in correctly classifying nodules as malignant or benign. CONCLUSION: FDG-PET scan as a single test was a better predictor of malignancy in solitary pulmonary nodules than the standard criteria using Bayesian analysis. FDG-PET scan can be a useful adjunct test in the evaluation of solitary pulmonary nodules.


Asunto(s)
Desoxiglucosa/análogos & derivados , Radioisótopos de Flúor , Pulmón/diagnóstico por imagen , Radiofármacos , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/epidemiología , Tomografía Computarizada de Emisión , Teorema de Bayes , Estudios de Casos y Controles , Femenino , Fluorodesoxiglucosa F18 , Humanos , Funciones de Verosimilitud , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada de Emisión/estadística & datos numéricos
9.
Chest ; 108(2): 441-6, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7634881

RESUMEN

BACKGROUND AND OBJECTIVE: Positron emission tomography (PET) utilizing 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) has been demonstrated to be highly accurate in differentiating benign from malignant pulmonary nodules. Transthoracic fine-needle aspiration biopsy (TTNA) is generally the initial procedure of choice in the evaluation of peripheral lesions suspected to be malignant. Our objective was to determine whether PET-FDG imaging, a noninvasive test, was equally efficacious as TTNA in the evaluation of lung lesions suspected to be malignant. PATIENT SELECTION: Thirty-three patients with 35 lung lesions who had undergone both PET-FDG imaging and TTNA were retrospectively selected from an ongoing prospective study of PET-FDG imaging in the evaluation of solitary pulmonary nodules. MEASUREMENTS: Diagnostic efficacy was determined by calculating sensitivity, specificity, positive and negative predictive value, and overall predictive accuracy for both PET-FDG imaging and TTNA in differentiating benign from malignant lesions. Complication rate also was documented for the two tests. RESULTS: The PET imaging correctly identified all 26 malignant lesions, including 21 lesions diagnosed by TTNA and 7 of the 9 benign lung lesions. The TTNA was positive for malignancy in 21 lung lesions and missed the diagnosis of malignancy in 5 lesions. Diagnostic sensitivity, specificity, positive and negative predictive value, and overall predictive accuracy was 100, 78, 93, 100, and 94% for PET imaging and 81, 100, 100, 64, and 86 for TTNA, respectively. Pneumothorax was documented in 16 patients (46%), and 9 patients (26%) required a chest tube. There were no complications with PET imaging. CONCLUSION: We conclude that PET imaging of the lung is as efficacious as TTNA, with less risk, and offers an alternate noninvasive option in the evaluation and management of lung lesions suspected to be malignant.


Asunto(s)
Desoxiglucosa/análogos & derivados , Radioisótopos de Flúor , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Pulmón/diagnóstico por imagen , Pulmón/patología , Tomografía Computarizada de Emisión/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja/efectos adversos , Biopsia con Aguja/métodos , Biopsia con Aguja/estadística & datos numéricos , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión/efectos adversos , Tomografía Computarizada de Emisión/estadística & datos numéricos
10.
Ann Thorac Surg ; 58(3): 698-703, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7944691

RESUMEN

Positron emission tomography detects increased glucose uptake in malignant tissue using the glucose analogue [2-18F]fluoro-2-deoxy-D-glucose. We reviewed the scans obtained in 62 patients with lung tumors. All had undergone computed tomography and had tissue-based diagnoses: 22 had adenocarcinomas, 12 had squamous cell carcinomas, 13 had other malignancies, 1 had organizing pneumonia, 1 had a hamartoma, and 13 had granulomas. Positron emission tomography with [2-18F]fluoro-2-deoxy-D-glucose identified 44 of 47 malignancies. Two of three false-negative findings were tumors that were 1 cm2 or less and the other was a bronchioloalveolar carcinoma. All three false-positive findings were granulomas. The sensitivity and specificity of the technique were 93.6% and 80%, respectively, and the positive and negative predictive values were 93.6% and 80%, respectively. The differential uptake ratio was determined in all 62 patients. The mean differential uptake ratio (+/- the standard error of the mean) for malignant tumors was 6.4 +/- 0.56 and that for benign tumors was 1.14 +/- 0.26 (p < 0.0001, t test). Twenty-five of the patients had N2 lymph nodes evaluated pathologically. Positron emission tomography with [2-18F]fluoro-2-deoxy-D-glucose identified negative N2 nodes in 19 of 22 patients (86%) with negative nodes and positive N2 nodes in 2 of 3 patients (66%) with positive nodes, including one instance missed by computed tomography.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Desoxiglucosa/análogos & derivados , Neoplasias Pulmonares/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Tomografía Computarizada de Emisión , Desoxiglucosa/administración & dosificación , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Fluorodesoxiglucosa F18 , Humanos , Neoplasias Pulmonares/clasificación , Neoplasias Pulmonares/patología , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Mediastino , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X
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