Search results for " Vitro"

Innovative ultrasound systems for preclinical studies: design and production of new instruments and set-ups for in vitro and in vivo experiments – Si…

Tolerance and M2 (alternative) macrophage polarization are related processes orchestrated by p50 nuclear factor {kappa}B.

2009

Cells of the monocyte-macrophage lineage play a central role in the orchestration and resolution of inflammation. Plasticity is a hallmark of mononuclear phagocytes, and in response to environmental signals these cells undergo different forms of polarized activation, the extremes of which are called classic or M1 and alternative or M2. NF-kappaB is a key regulator of inflammation and resolution, and its activation is subject to multiple levels of regulation, including inhibitory, which finely tune macrophage functions. Here we identify the p50 subunit of NF-kappaB as a key regulator of M2-driven inflammatory reactions in vitro and in vivo. p50 NF-kappaB inhibits NF-kappaB-driven, M1-polariz…

Viewpoint: On the hysteresis in the human Achilles tendon

2013

NG-monomethyl-L-arginine and NG-nitro-L-arginine inhibit endothelium-dependent relaxations in human isolated omental arteries.

1991

Abstract The L-arginine analogues NG-monomethyl-l-arginine (l-NMMA, 10−4  m) and NG-nitro-L-arginine methyl ester (l-NAME, 10−4  m), which specifically inhibit the synthesis of nitric oxide from l-arginine, significantly reduced acetylcholine-induced endothelium-dependent relaxations in rings of human omental arteries. The inhibitory potency of l-NMMA and l-NAME was similar. Addition of l-NMMA or l-NAME to the organ bath did not induce any significant changes in the resting tension of the tissues. The effects of l-NMMA were reversed by l-arginine (3 × 10−4  m). The l-NMMA enantiomer, d-NMMA (10−4  m), did not influence either the basal tone of the preparation or the relaxing effects of acet…

Properties and significance of apoFNR as a second form of air-inactivated [4Fe-4S]·FNR of Escherichia coli

2005

The active form of the oxygen sensor fumarate nitrate reductase regulator (FNR) of Escherichia coli contains a [4Fe-4S] cluster which is converted to a [2Fe-2S] cluster after reaction with air, resulting in inactivation of FNR. Reaction of reconstituted [4Fe-4S].FNR with air resulted within 5 min in conversion to apoFNR. The rate was comparable to the rate known for [4Fe-4S].FNR/[2Fe-2S].FNR cluster conversion, suggesting that apoFNR is a product of [2Fe-2S].FNR decomposition and a final form of air-inactivated FNR in vitro. Formation of apoFNR and the redox state of the cysteinyl residues were determined in vitro by alkylation. FNR contains five cysteinyl residues, four of which (Cys20, Cy…

Prediction of properties of chiral compounds by molecular topology

1998

Abstract A common assumption in chemistry is that chiral behavior is associated with 3-D geometry. However, chiral information is related to symmetry, which allows the topological handling of chiral atoms by weighted graphs and the calculation of new descriptors that give a weight to the corresponding entry in the main diagonal of the topological matrix. In this study, it is demonstrated that, operating in this way, chiral topological indices are obtained that can differentiate the pharmacological activity between pairs of enantiomers. The 50% inhibitory concentration (IC50) values of the D2 dopamine receptor and the σ receptor for a group of 3-hydroxy phenyl piperidines are specifically pr…

Effects of magnesium chloride on the contractile response of uterus to several agonists in Ca-free solution

1987

Abstract The effects of MgCl2 on the oestrogen-dominated rat uterus have been examined. Tissues were preincubated in a Ca2+- and Mg2+-free medium containing 3 mM EDTA. Most experiments were subsequently performed in a similar medium containing either no EDTA or EDTA (1 mM). When MgCl2 was added cumulatively (1–32 mM) no contractile responses were obtained in Ca,Mg-free medium or in Ca,Mg-free high K+ solution. When 2 mM CaCl2 as added, a sustained contraction was obtained. Subsequent addition of cumulative concentrations of MgCl2 caused concentration-dependent relaxation. Oxytocin, 2 μM, produced a small and sustained contraction in a Ca,Mg-free medium. Addition of MgCl2, 2 mM, increased th…

PET Imaging of the Impact of Extracellular pH and MAP Kinases on the p-Glycoprotein (Pgp) Activity

2012

The functional activity of p-glycoprotein (Pgp) can be increased in vitro by an extracellular acidosis via activation of MAP kinases (p38, ERK1/2). In order to study these effects in vivo a new (68)Ga-labeled PET tracer was developed which serves as a substrate of the Pgp and therefore indirectly mirrors the Pgp activity. For in vivo studies, experimental tumors were imaged under acidic conditions (inspiratory hypoxia, injection of lactic acid) and during inhibition of MAP kinases in a μ-PET system. In vitro, [(68)Ga]MFL6.MZ showed an accumulation within the cells of about 20% which was increased to 30% by Pgp inhibition. In solid tumors a marked tracer uptake was observed showing spatial h…

Nuevas metodologías para la selección no invasiva de embriones humanos en tratamientos de reproducción asistida: introducción de la inteligencia arti…

2023

La evaluación y selección de embriones en los tratamientos de fecundación in vitro (FIV) se realiza manualmente de forma convencional, mediante observaciones puntuales bajo el microscopio durante el desarrollo embrionario. Dicho análisis altera las condiciones de cultivo, pudiendo afectar a las tasas de éxito del tratamiento de reproducción asistida. La introducción de la microscopía de lapso de tiempo o time-lapse, ha hecho posible un seguimiento continuo de los embriones in vitro. De esta forma, se obtiene rutinariamente gran cantidad de información en formato de imágenes grabadas. Hoy en día, el análisis de este material todavía se realiza manualmente y las imágenes se utilizan sobre tod…

Macrophage: SHIP of Immunity

2014

Immunology. Why does it exist? Two words. Cure disease. People get diseases. “Test tubes” do not. People fund immunologists for solutions to their health problems. But, immunologists often study leukocytes in test tubes – the laboratory – away from diseases. Why? Because much can be learned from analyzing cellular biochemistry and behaviors in vitro that cannot be ascertained when leukocytes are in animals. At the same time, isolated leukocyte reactions often do not reflect how the immune system operates as a unit. So, it is critical to verify in vitro observations in vivo. Among leukocytes, macrophages are the central initiating and directing element in immune systems, and serve this role …