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1.
Curr Pharm Biotechnol ; 22(2): 262-273, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32532192

RESUMEN

BACKGROUND: The anticancer effects of Phyllanthus amarus extract on various cancer cells have been investigated, however, the effects of its major constituents on HCT116 human colorectal cancer cells have not been reported. OBJECTIVE: In the present study, we investigated the cytotoxic effect of 80% ethanol extract of P. amarus and its marker constituents (phyllanthin, hypophyllanthin, gallic acid, niranthin, greraniin, phyltetralin, isolintetralin, corilagin and ellagic acid) on HCT116 and their underlying mechanisms of action. METHODS: Their antiproliferative and apoptotic effects on HCT 116 were performed using MTT assay and flow cytometric analysis, respectively, while caspases 3/7, 8 and 9 activities were examined using the colorimetric method. The expression of cleaved poly ADP ribose polymerase enzyme (PARP) and cytochrome c proteins was investigated by the immune-blot technique. RESULTS AND DISCUSSION: HPLC and LC-MS/MS analyses demonstrated that the extract contained mainly lignans and polyphenols. The plant samples markedly suppressed the growth and expansion of HCT116 cells in a concentration- and time-dependent manner with no toxicity against normal human fibroblast CCD18 Co. P. amarus extract, phyllanthin and gallic acid induced mode of cell death primarily through apoptosis as confirmed by the exteriorization of phosphatidylserine. Caspases 3/7, 8, and 9 activities increased in a concentration-dependent manner following 24h treatment. The expressions of cleaved PARP (Asp 214) and cytochrome c were markedly upregulated. CONCLUSION: P. amarus extract, phyllanthin and gallic acid exhibited an apoptotic effect on HCT116 cells through the caspases-dependent pathway.


Asunto(s)
Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Neoplasias del Colon/enzimología , Lignanos/farmacología , Phyllanthus , Extractos Vegetales/farmacología , Polifenoles/farmacología , Apoptosis/fisiología , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Cromatografía Liquida/métodos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Relación Dosis-Respuesta a Droga , Células HCT116 , Humanos , Lignanos/aislamiento & purificación , Lignanos/uso terapéutico , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Polifenoles/aislamiento & purificación , Polifenoles/uso terapéutico , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Espectrometría de Masas en Tándem/métodos
2.
BJOG ; 126(7): 875-883, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30666783

RESUMEN

OBJECTIVE: To assess the cost-effectiveness of treatment with nifedipine compared with atosiban in women with threatened preterm birth. DESIGN: An economic analysis alongside a randomised clinical trial (the APOSTEL III study). SETTING: Obstetric departments of 12 tertiary hospitals and seven secondary hospitals in the Netherlands and Belgium. POPULATION: Women with threatened preterm birth between 25 and 34 weeks of gestation, randomised for tocolysis with either nifedipine or atosiban. METHODS: We performed an economic analysis from a societal perspective. We estimated costs from randomisation until discharge. Analyses for singleton and multiple pregnancies were performed separately. The robustness of our findings was evaluated in sensitivity analyses. MAIN OUTCOME MEASURES: Mean costs and differences were calculated per woman treated with nifedipine or atosiban. Health outcomes were expressed as the prevalence of a composite of adverse perinatal outcomes. RESULTS: Mean costs per patients were significantly lower in the nifedipine group [singleton pregnancies: €34,897 versus €43,376, mean difference (MD) -€8479 [95% confidence interval (CI) -€14,327 to -€2016)]; multiple pregnancies: €90,248 versus €102,292, MD -€12,044 (95% CI -€21,607 to € -1671). There was a non-significantly higher death rate in the nifedipine group. The difference in costs was mainly driven by a lower neonatal intensive care unit admission (NICU) rate in the nifedipine group. CONCLUSION: Treatment with nifedipine in women with threatened preterm birth results in lower costs when compared with treatment with atosiban. However, the safety of nifedipine warrants further investigation. TWEETABLE ABSTRACT: In women with threatened preterm birth, tocolysis using nifedipine results in lower costs when compared with atosiban.


Asunto(s)
Nifedipino/economía , Nacimiento Prematuro/economía , Tocolíticos/economía , Vasotocina/análogos & derivados , Análisis Costo-Beneficio , Femenino , Humanos , Nifedipino/uso terapéutico , Embarazo , Embarazo Múltiple , Nacimiento Prematuro/prevención & control , Atención Prenatal/economía , Tocolíticos/uso terapéutico , Vasotocina/economía , Vasotocina/uso terapéutico
4.
Case Rep Endocrinol ; 2012: 739375, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22937298

RESUMEN

An 18-year-old negroid woman presented with progressive cramps in both hands. She was Jamaican and had moved to The Netherlands 8 months before. On physical examination Trousseau's sign was positive. Laboratory analysis showed severe hypocalcaemia (1.17 mmol/L) and hyperphosphatemia (2.0 mmol/L). Urinary excretion of both calcium (0.8 mmol/day) and phosphate (5 mmol/day) was low, as is seen in hypoparathyroidism. However, the PTH level was increased (22.1 pmol/L), whereas 25-(OH)-vitamin D was low (31 nmol/L). An Ellsworth-Howard test showed only a fivefold increase in urinary phosphate excretion after administration of synthetic PTH, supporting the diagnosis pseudohypoparathyroidism. Upon treatment with calcium supplementation and alfacalcidol, her symptoms disappeared. Pseudohypoparathyroidism (PHP) is a rare hereditary disorder resembling hypoparathyroidism, although plasma PTH levels are elevated. PHP is caused by alterations in the PTH receptor, inducing target tissue resistance to PTH. This results in hypocalcaemia and hyperphosphatemia, while PTH levels are elevated. The diagnosis is confirmed by the Ellsworth-Howard test, which will show a 100-fold increase in phosphate excretion if the PTH receptor functions properly. Treatment is lifelong supplementation of calcium and alfacalcidol. In our patient, symptoms were probably evoked by the lack of sunlight in Dutch winter, decreasing vitamin D levels and thereby aggravating hypocalcaemia.

5.
Food Chem ; 134(4): 1919-25, 2012 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23442639

RESUMEN

Pumpkin, a member of the Cucurbitaceae family has been used frequently as functional medicines for therapeutic use. Several phytochemicals such as polysaccharides, phenolic glycosides, 13-hydroxy-9Z, 11E-octadecatrienoic acid from the leaves of pumpkin, proteins from germinated seeds, have been isolated. Here the influence of pH, ionic strength, and temperature on the properties and stability of oil bodies from pumpkin (Cucurbita) were determined with a view to patterning oil body size and structure for future therapeutic intervention. Oil bodies from pumpkin seeds were extracted, isolated, characterised using optical microscopy, zeta potential and particle size distribution obtained. During microscopic analysis, the oil bodies were more intact and in an integrated form at the time of extraction but were ruptured with time. Water extracted oil bodies were spherical for all four layers where cream had larger oil bodies then upper curd. Lower curd and supernatant had considerably smaller size with lower curd densely packed and seemed to be rich in oil bodies than any of the four layers. At pH 3, in the absence of salt, the zeta potential is approximately +30 mV, but as the salt concentration increases, the ζ potential rises at 10 mM but then decreases over the salt range. This trend continues for the upper curd, lower curd and the supernatant and the degree of the reduction (mV) in zeta potential is of the order cream

Asunto(s)
Cucurbita/química , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Semillas/química , Calor , Concentración de Iones de Hidrógeno , Tamaño de la Partícula
6.
Methods ; 54(1): 136-44, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21276851

RESUMEN

In 1962 H. Fujita (H. Fujita, Mathematical Theory of Sedimentation Analysis, Academic Press, New York, 1962) examined the possibility of transforming a quasi-continuous distribution g(s) of sedimentation coefficient s into a distribution f(M) of molecular weight M for linear polymers using the relation f(M)=g(s)·(ds/dM) and showed that this could be done if information about the relation between s and M is available from other sources. Fujita provided the transformation based on the scaling relation s=κ(s)M(0.5), where κ(s) is taken as a constant for that particular polymer and the exponent 0.5 essentially corresponds to a randomly coiled polymer under ideal conditions. This method has been successfully applied to mucus glycoproteins (S.E. Harding, Adv. Carbohyd. Chem. Biochem. 47 (1989) 345-381). We now describe an extension of the method to general conformation types via the scaling relation s=κM(b), where b=0.4-0.5 for a coil, ∼0.15-0.2 for a rod and ∼0.67 for a sphere. We give examples of distributions f(M) versus M obtained for polysaccharides from SEDFIT derived least squares g(s) versus s profiles (P. Schuck, Biophys. J. 78 (2000) 1606-1619) and the analytical derivative for ds/dM performed with Microcal ORIGIN. We also describe a more direct route from a direct numerical solution of the integral equation describing the molecular weight distribution problem. Both routes give identical distributions although the latter offers the advantage of being incorporated completely within SEDFIT. The method currently assumes that solutions behave ideally: sedimentation velocity has the major advantage over sedimentation equilibrium in that concentrations less than 0.2mg/ml can be employed, and for many systems non-ideality effects can be reasonably ignored. For large, non-globular polymer systems, diffusive contributions are also likely to be small.


Asunto(s)
Polímeros/química , Polisacáridos/química , Ultracentrifugación/métodos , Alginatos/química , Quitosano/química , Glucanos/química , Ácido Glucurónico/química , Glicoconjugados/química , Ácidos Hexurónicos/química , Mananos/química , Modelos Químicos , Peso Molecular , Mucinas/química , Pectinas/química , Polisacáridos Bacterianos/química , Vacunas Conjugadas/química
7.
Plant Physiol ; 121(2): 363-72, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10517827

RESUMEN

The changes in cell wall polysaccharides and selected cell wall-modifying enzymes were studied during the development of green bean (Phaseolus vulgaris L.) pods. An overall increase of cell wall material on a dry-weight basis was observed during pod development. Major changes were detected in the pectic polymers. Young, exponentially growing cell walls contained large amounts of neutral, sugar-rich pectic polymers (rhamnogalacturonan), which were water insoluble and relatively tightly connected to the cell wall. During elongation, more galactose-rich pectic polymers were deposited into the cell wall. In addition, the level of branched rhamnogalacturonan remained constant, while the level of linear homogalacturonan steadily increased. During maturation of the pods, galactose-rich pectic polymers were degraded, while the accumulation of soluble homogalacturonan continued. During senescence there was an increase in the amount of ionically complexed pectins, mainly at the expense of freely soluble pectins. The most abundant of the enzymes tested for was pectin methylesterase. Peroxidase, beta-galactosidase, and alpha-arabinosidase were also detected in appreciable amounts. Polygalacturonase was detected only in very small amounts throughout development. The relationship between endogenous enzyme levels and the properties of cell wall polymers is discussed with respect to cell wall synthesis and degradation.


Asunto(s)
Fabaceae/crecimiento & desarrollo , Plantas Medicinales , Polisacáridos/metabolismo , Semillas/metabolismo , Hidrolasas de Éster Carboxílico/metabolismo , Fabaceae/metabolismo , Peroxidasas/metabolismo , Poligalacturonasa/metabolismo , Polisacáridos/aislamiento & purificación
8.
Audiology ; 32(4): 213-24, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8343078

RESUMEN

Click-evoked oto-acoustic emissions (EOAEs) were recorded in 1036 ears of healthy newborns and in 71 normal-hearing adult ears. Newborns aged between 3 and 238 h were examined in a separate but not silent room of the obstetric ward. The adults were tested in a quiet but not sound-treated room. The recordings were more difficult in the newborn than in the adult, which was mirrored in recording parameters such as the time required for measurement (up to 7 min in newborns vs. 1-2 min in adult ears). Recording was always successful in adults, while retests were necessary in 4% of newborns. Also the artefact-rejection level and the stimulus stability were more favourable in adults. Still, EOAE recording for screening purposes in newborns seems feasible. Response levels in newborns (range 1.6-38.6; mean 20.2 dB SPL) appear to be higher than in adults (range 2.7-20.6; mean 12.8 dB SPL). The overall prevalence of EOAEs in newborns amounted to 93.4% and appeared to be age related. It rises from 78% in ears from newborns younger than 36 h to 99% in ears of newborns older than 108 h. This rise may be related to the middle ear clearance of amniotic fluid in the first days post partum. The prevalence in newborns older than 3-4 days is comparable with the prevalence of 97.2% in adults. Therefore, newborns should not be screened before the age of 4 days. In search of an objective EOAE detection variable, the prevalence of EOAEs for different age groups was calculated for various criterion values of reproducibility. These prevalences were compared to subjectively scored EOAE prevalences in the same age groups. A reproducibility criterion of about 50% appears to be useful for mass screening in newborns.


Asunto(s)
Cóclea/fisiología , Audición/fisiología , Recién Nacido , Estimulación Acústica , Factores de Edad , Oído Interno/fisiología , Femenino , Pruebas Auditivas , Humanos , Masculino , Ruido/efectos adversos , Prevalencia , Reproducibilidad de los Resultados
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