Integration of Ca signaling regulates the breast tumor cell response to simvastatin and doxorubicin.

Recent studies have suggested that the lipid-lowering agent simvastatin holds great promise as a cancer therapeutic; it inhibits the growth of multiple tumors, including triple-negative breast cancer. Doxorubicin- and simvastatin-induced cytotoxicity has been associated with the modulation of Ca signaling, but the underlying mechanisms remain incompletely understood. Here we identify how Ca signaling regulates the breast tumor cell response to doxorubicin and simvastatin.

Synergistic promoting effects of pentoxifylline and simvastatin on the apoptosis of triple-negative MDA-MB-231 breast cancer cells.

Pentoxifylline (PTX), a xanthine family molecule and simvastatin (SIM), an anti-hypercholesterolemic agent, have recently been considered as sensitizers to chemotherapy and radiotherapy. The present in vitro study evaluated their antitumor synergistic effects on MDA‑MB‑231 breast cancer cells characterized by the triple‑negative phenotype (TNP). The anti-proliferative effects of these two agents were evaluated by MTT and clonogenic assays.

Pyr3, a TRPC3 channel blocker, potentiates dexamethasone sensitivity and apoptosis in acute lymphoblastic leukemia cells by disturbing Ca(2+) signaling, mitochondrial membrane potential changes and reactive oxygen species production.

Dexamethasone (Dex) is used as a chemotherapeutic drug in the treatment of acute lymphoblastic leukemia (ALL) because of its capacity to induce apoptosis. However, some ALL patients acquire resistance to glucocorticoids (GC). Thus, it is important to explore new agents to overcome GC resistance.

Effect of molecular structure of sulphonated polyimide membranes on water sorption.

Water sorption in sulphonated polyimides with or without ionic block structure was analysed with Feng's new dual mode model. The effect of their molecular structure that determines the chain organisation in the solid materials was analysed by using the model parameters. The model parameters Cp and A' correspond to the sorbed water molecules on the first layer close to the ionic groups and on the subsequent layers, respectively.

Rac3 induces a molecular pathway triggering breast cancer cell aggressiveness: differences in MDA-MB-231 and MCF-7 breast cancer cell lines.

Background: Rho GTPases are involved in cellular functions relevant to cancer. The roles of RhoA and Rac1 have already been established. However, the role of Rac3 in cancer aggressiveness is less well understood.

Importance of local hypoxia on endothelial phenotype for an in vitro approach to bone marrow angiogenesis.

The vasculature of bone marrow differs from that in other organs, and its characteristics should be considered when exploring the medullar angiogenesis associated with hematological malignancies. We show here that the human bone marrow sinusoidal cell line HBME-1 has a specific expression pattern of angiogenic factors and receptors, characterized by a unique VEGFR3(+), Tie2(-) signature, that resembles the in vivo pattern. Moreover, the HBME-1 cultured for up to 3 days in hypoxic conditions, similar to those found in the bone marrow, specifically downregulated expression of VEGFR1, VEGFR2 and ETAR.

Survival of cord blood haematopoietic stem cells in a hyaluronan hydrogel for ex vivo biomimicry.

Haematopoietic stem cells (HSCs) and haematopoietic progenitor cells (HPCs) grow in a specified niche in close association with the microenvironment, the so-called 'haematopoietic niche'. Scaffolds have been introduced to overcome the liquid culture limitations, mimicking the presence of the extracellular matrix (ECM). In the present study the hyaluronic acid scaffold, already developed in the laboratory, has been used for the first time to maintain long-term cultures of CD34⁺ haematopoietic cells obtained from human cord blood.

Rac-1 GTPase controls the capacity of human leukaemic lymphoblasts to migrate on fibronectin in response to SDF-1α (CXCL12).

Acute lymphoblastic leukaemia (ALL) is characterized by malignant cell infiltration of bone marrow, requiring chemotactic response to SDF-1α. Using time-lapse video, we measured the velocity of ALL cells on fibronectin, and found that SDF-1α increased their migration activity for 2 h, but had no effect after 4h, following internalization of its receptor CXCR4. Transfection of ALL cells with dominant-negative Rac1 mutant significantly prolonged their chemotactic response to SDF-1α, and this effect was associated with an alteration of CXCR4 internalization.

Permeation properties of poly(m-xylene adipamide) membranes.

The permeation properties of a semiaromatic polyamide, the poly(m-xylene adipamide) (MXD6), were investigated by water and carbon dioxide permeation experiments (pervaporation and gas permeation tests). Complementary microstructure informations were obtained from calorimetric measurements. Amorphous and semicrystalline MXD6 membranes were studied.

VE-statin/egfl7 regulates vascular elastogenesis by interacting with lysyl oxidases.

We previously characterized VE-statin/egfl7, a protein that is exclusively secreted by endothelial cells and modulates smooth muscle cell migration. Here, we show that VE-statin/egfl7 is the first known natural negative regulator of vascular elastogenesis. Transgenic mice, expressing VE-statin/egfl7 under the control of keratin-14 promoter, showed an accumulation of VE-statin/egfl7 in arterial walls where its presence correlated with an impaired organization of elastic fibres.

Operant conditioning of the visual smooth pursuit in young infants.

Smooth pursuit is a complex behaviour which is not considered as totally functional at birth. The lack of maturation of the visuo-motor systems is generally invoked to explain this phenomenon. However, if this oculomotor response is an operant behaviour, an alternate explanation may be found in the absence of previous confrontation with the environmental contingencies.

Activation of dopamine D4 receptor inhibits an L-type calcium current in cerebellar granule cells.

The functions of the D4 receptor, a newly cloned D2-like receptor, as well as the identity of cells expressing it, are still poorly defined. Using quantitative polymerase chain reaction we detected the messenger RNA of the D4, but not other D2-like receptor, in cultured granule cells from neonatal rat cerebellum. In these neurons, dopamine reduced high-voltage-activated calcium current, with a pharmacology corresponding to that of the D4 receptor.

Quantitative assessment of the static properties of the oculo-motor system by the photo-oculographic technique.

The paper addresses the problems raised by the application of the photo-oculographic technique to the quantification of static orientations of the eye in ophthalmology. Eye orientations are determined from the relative positions of corneal reflex and pupil images. The relationship between the positions of these images and the angular rotations of the eye is studied with an optical model of the anterior chamber of the eye.

Changes in levels of argininosuccinate lyase mRNA during induction by glucagon and cyclic AMP in cultured foetal-rat hepatocytes.

During the perinatal period, the activity of the urea-cycle enzyme argininosuccinate lyase (ASL) is regulated by glucocorticoids, glucagon and insulin. In this study, the effects of glucagon and cyclic AMP (cAMP) analogues were examined on the synthesis of ASL and on the level of its corresponding mRNA in cultured foetal hepatocytes. Northern-blot analysis revealed that these agents only gave a transient induction of ASL mRNA amount, which reached a peak at 6 h and declined thereafter.

[Evaluation of spatial discrimination performances of newborn infants with the visual pursuit of structured stimuli].

Pursuit eye movements have been recorded with the photo-oculographic technique from newborn infants during the presentation of stimulations specific for spatial discrimination functions. 72.5 per cent of 51 subjects whose eye movements have been recorded have successfully followed stimuli of spatial frequency up to 0.

[Eye controlled microscope used in ophthalmic microsurgery].

This article presents a system of oculomotor control of the microscope used in ophthalmic microsurgery. An eye movement sensor has been integrated within the microscope lens. The information provided by this sensor is used to control the position of the microscope with no alteration of the surgeon's visual functions and no interference with his visual sensori-motor reflexes.

Butyrate blocks the accumulation of CDC2 mRNA in late G1 phase but inhibits both the early and late G1 progression in chemically transformed mouse fibroblasts BP-A31.

Sodium butyrate (6 mM) blocks the resumption of the cell division cycle in serum-deprived chemically transformed Balb/c-3T3 mouse fibroblasts (BP-A31). The inhibition of G1 progression by sodium butyrate is not restricted to a specific mitogenic signaling pathway and is equally effective when tetradecanoyl phorbol acetate (TPA), insulin, or fetal calf serum (FCS) is used as inducer. The inhibitor acts in early as well as late G1 phase as indicated by experiments in which inhibitor was added and withdrawn at different times after restimulation of quiescent cells by FCS.

Expression of argininosuccinate lyase mRNA in foetal hepatocytes. Regulation by glucocorticoids and insulin.

Argininosuccinate lyase (ASL), the fourth enzyme of the urea cycle, belongs to a group of liver enzymes appearing in the late foetal period in the rat. Several hormones, including glucocorticosteroids and insulin have been implicated in the control of the development of this enzyme activity. In this study, the cloned cDNA was used to measure the relative abundance of ASL mRNA in the livers of rats at various stages of perinatal development and in cultured foetal hepatocytes during hormonal manipulations.

[Analysis of vergence movements using differential photo-oculography].

Analysis of vergence troubles is weight by an heavy handicap. In clinical conditions it is easy to value the static vergence balance with a great lot of tests. On the contrary examination of kinetic vergence pattern is generally neglected.

[Comparative study of electrooculographic and photooculographic recordings].

The authors present the results of clinical application of a new invasive real time method for ocular movement recording. There is an optical system which measures the gaze direction from the video signals of five reflected corneal dots and pupil image. Their study is based upon 110 simultaneous P.

[A new technic for recording eye movements by image processing. Principle and method].

Nowadays, electro-oculography remains the only clinical method for ocular movement recording which is largely used in daily practise, but it has many drawbacks and limits. Till now the photo-oculographic technics have been only applied in laboratory conditions. A new differential photo-oculographic procedure is presented.

[Differential photo-oculography of vertical and oblique movements].

Up to now EOG has been the only method used to record ocular movements in daily practice. However such a mean has various drawbacks and limits. It has two main gaps: firstly for vertical movements because the interference discharges related with palpebral movements and blinkings; on the other hand for oblique movements because the unequal transmission of EOG potential towards the orbital rim.

[Asymmetry of visual perceptive activity of faces and emotional facial expressions].

Eye movements were studied in 40 right-handed subjects during perception of symmetrical chimerical faces. These movements were recorded using an original system based on a differential optical method for the detection of corneal reflection and of the pupil made shiny. Under basal conditions, the first fixation was usually located in the left visual hemifield.