Search results for "CELLULAR"

Trans-epithelial transport of the betalain pigments indicaxanthin and betanin across Caco-2 cell monolayers and influence of food matrix.

2012

Purpose: This study investigated the absorption mechanism of the phytochemicals indicaxanthin and betanin and the influence of their food matrix (cactus pear and red beet) on the intestinal transport. Methods: Trans-epithelial transport of dietary-consistent amounts of indicaxanthin and betanin in Caco-2 cell monolayers seeded on TranswellR inserts was measured in apical to basolateral (AP-BL) and basolateral to apical (BL-AP) direction, under an inwardly directed pH gradient (pH 6.0/7.4, AP/BL) mimicking luminal and serosal sides of human intestinal epithelium. The effect of inhibitors of membrane transporters on the absorption was also evaluated. Contribution of the paracellular route was…

Micellar liquid chromatography for prediction of drug transport.

2000

Abstract The vast majority of well absorbed drugs are transported passively across the cell membranes. Physicochemical descriptors of drug molecules that are believed to influence transcellular transport are routinely used to predict drug absorption by means of complex mathematical models. In this paper, a new in vitro method, based on the retention data in micellar liquid chromatography (MLC), is validated for the prediction of passive drug absorption. The retention of a heterogeneous drugs set in MLC using Brij 35 as surfactant in the mobile phase is compared with the retention data reported in literature obtained in red cell membrane lipid liposomes, human red cell membranes vesicles (ve…

Significance of passively induced stretch reflexes on achilles tendon force enhancement

1998

An in vivo buckle transducer technique was applied to study the reflex contribution to ATF enhancement during passive dorsiflexion stretches. Single stretches led to a linear ATF increase in the absence of an EMG reflex response, whereas clear ATF enhancement over the passive component occurred 13-15 ms after the onset of EMG responses. To quantify the reflexly induced increase in ATF, the stretched position was maintained. The mean reflex effect was two to four times greater than the passive stretch effect.

Natural killer cell activity as a prognostic parameter in the progression to AIDS.

1988

Characterization of cellular and molecular responses of Actinia equina (Linnaeus, 1758)

2014

A qualitative model of the HIV vital cycle

1992

Qualitative modelling is a recent artificial intelligence approach to physical system modelling. This approach has been successfully applied in several fields. On the basis of an analysis and qualitative modelling of cell growth, we reckon that a qualitative model of the vital cycle of HIV can be proposed, including the phases in which HIV can be attacked. The actions of antiviral drugs can also be qualitatively modelled, provided their action mechanism is known, even only in a broad sense.

Aequorin-expressing yeast emits light under electric control

2011

In this study, we show the use of direct external electrical stimulation of a jellyfish luminescent calcium-activated protein, aequorin, expressed in a transgenic yeast strain. Yeast cultures were electrically stimulated through two electrodes coupled to a standard power generator. Even low (1.5. V) electric pulses triggered a rapid light peak and serial light pulses were obtained after electric pulses were applied periodically, suggesting that the system is re-enacted after a short refraction time. These results open up a new scenario, in the very interphase between synthetic biology and cybernetics, in which complex cellular behavior might be subjected to electrical control.

Different pathways for the nuclear import of yeast RNA polymerase II

2015

Recent studies suggest that RNA polymerase II (Pol II) has to be fully assembled before being imported into the nucleus, while other reports indicate a distinct mechanism to import large and small subunits. In yeast, Iwr1 binds to the holoenzyme assembled in the cytoplasm and directs its nuclear entry. However, as IWR1 is not an essential gene, Iwr1-independent pathway(s) for the nuclear import of Pol II must exist. In this paper, we investigate the transport into the nucleus of several large and small Pol II subunits in the mutants of genes involved in Pol II biogenesis. We also analyse subcellular localization in the presence of drugs that can potentially affect Pol II nuclear import. Our…

Insufficienza renale acuta in paziente con carcinoma epatocellulare sottoposto a chemioembolizzazione transarteriosa

2007

Transarterial chemoembolization (TACE) is included among the wide therapeutic tools for the treatment of hepatocellular carcinoma (HCC), tumour with high frequency and malignancy. The approach is invasive and, beyond the discomfort for the patient, it is charged by a number of side effects and complications. In this study we report the case of renal acute failure of hypovolemic origin, as a consequence of a TACE in a patient suffering from HCC, occurred after one week of intervention. The different possible mechanisms involved in the pathogenesis of this complication are discussed.

Leukocyte migration test (LMT) in patients with thyroid disease: the response to human thyroid subcellular fractions.

1981

The response of circulating leukocytes to thyroid subcellular fractions was investigated in 19 patients with Graves' disease, 15 patients with Hashimoto's thyroiditis, 7 patients with toxic adenoma, 19 patients with nontoxic goiter and in 10 healthy students as control subjects. For this purpose, the leukocyte migration test of Soborg and Bendixen was performed against human crude thyroid extract (CTE), cell plasma membranes, nuclei, ribosomes, mitochondria and microsomes. Our results show positive LMT against: 1) CTE in patients with Graves' disease (61 +/- 13, p less than 0.001) and Hashimoto's thyroiditis (65 +/- 11, p less than 0.001) compared to controls (90 +/- 11); 2) cell plasma mem…