Transplantation of mesenchymal stem cells cultured on biomatrix support induces repairing of digestive tract defects, in animal model.

Transplanted mesenchymal stem cells (MSCs) appear to play a significant role in adult tissue repair. The aim of this research was to obtain MSCs enriched, three dimensional (3D) patches for transplant, and to test their ability to induce repair of iatrogenic digestive tract defects in rats. MSCs were obtained from human and rat bone marrow, cultured in vitro, and seeded in a collagen-agarose scaffold, where they showed enhanced viability and proliferation.

Low basal levels of circulating adiponectin in patients undergoing coronary stenting predict in-stent restenosis, independently of basal levels of inflammatory markers: lipoprotein associated phospholipase A2, and myeloperoxidase.

Objective: The aim of this study was to find a pre-interventional marker with the capacity to predict in-stent restenosis (ISR). Considering the anti-atherosclerotic role of adiponectin (APO), an adipocytokine with anti-inflammatory, anti-proliferative, anti-oxidative and anti-thrombotic properties, low plasma levels of APO might be correlated with the risk of ISR. We investigated the correlations between the plasma levels of APO and two markers of inflammation: lipoprotein associated phospholipase A2 (Lp-PLA2) and myeloperoxidase (MPO).

Imatinib inhibits spontaneous rhythmic contractions of human uterus and intestine.

The interstitial cells of Cajal (ICC) in the digestive tract and ICC-like cells in extradigestive organs express the c-kit tyrosine-kinase receptor, and have been implicated as pacemakers of smooth muscle spontaneous activity. We used imatinib mesylate (Glivec) to investigate whether c-kit activity of Cajal-like cells in human myometrium is involved in spontaneous rhythmic contractions of human uterine smooth muscle, taking intestinal smooth muscle as a reference tissue. We show that imatinib concentration-dependently inhibited the myogenic contractions of human myometrium in the organ bath, while it significantly affected noradrenaline or K(+)-induced contractions only at concentrations exceeding 50 muM.

[Expression of stem cell markers on fetal and tumoral human liver cells in primary culture].

Hepatic stem cells can be identified by the expression of putative markers such as CD117 (c-kit), CD90 (Thy-1), CD34, and HLA-DR. We have identified populations expressing these markers in both fetal and tumoral human liver by flow cytometry, using monoclonal antibodies against CD90, CD117, CD34, and HLA-DR. In tumoral liver CD117+/CD90+ cells were found in decreasing number from the neoplastic (2.

Vesicle traffic through intercellular bridges in DU 145 human prostate cancer cells.

We detected cell-to-cell communication via intercellular bridges in DU 145 human prostate cancer cells by fluorescence microscopy. Since DU 145 cells have deficient gap junctions, intercellular bridges may have a prominent role in the transfer of chemical signals between these cells. In culture, DU 145 cells are contiguous over several cell diameters through filopodial extensions, and directly communicate with adjacent cells across intercellular bridges.

Apoptotic rate in patients with myelodisplastic syndrome treated with modulatory compounds of pro-apoptotic cytokines.

Excessive apoptosis has a central role in ineffective hematopoiesis in myelodysplastic syndrome (MDS). The aim of the study was to quantify apoptosis and Bcl-2 expression in patients with MDS and to use these parameters in the evaluation of treatment efficacy with compounds modulating proapoptotic cytokines. Bone marrow (BM) samples from eight MDS patients were studied: four with refractory anemia and four with refractory anemia with ringed sideroblasts.

Significance of platelet-activating factor acetylhydrolase in patients with non-insulin-dependent (type 2) diabetes mellitus.

Background: Non-insulin dependent diabetes mellitus (NIDDM) represents an independent risk factor for cardiovascular diseases (CVD), being characterized by a continuous low-grade inflammation and endothelial activation state. Plasma platelet - activating factor - acetylhydrolases (PAF-AHs) are a subgroup of Ca(2+)-independent phospholipase A(2) family (also known as lipoprotein-associated phospholipases A(2)) that hydrolyze and inactivate the lipid mediator platelet-activating factor (PAF) and/or oxidized phospholipids. This enzyme is considered to play an important role in inflammatory diseases and atherosclerosis.

Dantrolene protects neurons against kainic acid induced apoptosis in vitro and in vivo.

Apoptotic cell death induced by kainic acid (KA) in cultures of rat cerebellar granule cells (CGC) and in different brain regions of Wistar rat pups on postnatal day 21 (P21) was studied. In vitro, KA (100-500 microM) induced a concentration-dependent loss of cell viability in MTT assay and cell death had apoptotic morphology as studied by chromatin staining with propidium iodide (PI). In vivo, twenty-four hours after induction of status epilepticus (SE) by an intraperitoneal KA injection (5 mg/kg) we quantified apoptotic cells in hippocampus (CA1 and CA3), parietal cortex and cerebellum using PI staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) technique.

Selective protection by phosphatidic acid against staurosporine-induced neuronal apoptosis.

Phosphatidic acid, the main product of lipid breakdown through phospholipase D activation, has been implicated in important signal transduction pathways able to influence cell fate in many ways. The purpose of this work was to determine possible effects of phosphatidic acid on neuronal cell death pathways. Here we used cerebellar granular cell cultures and cell death was triggered with either staurosporine or H(2)O(2).

Messenger molecules of the phospholipase signaling system have dual effects on vascular smooth muscle contraction.

Background and methods. In order to investigate the role of phospholipases and their immediately derived messengers in agonist-induced contraction of portal vein smooth muscle, we used the addition in the organ bath of exogenous molecules such as: phospholipases C, A(2), and D, diacylglycerol, arachidonic acid, phosphatidic acid, choline. We also used substances modulating activity of downstream molecules like protein kinase C, phosphatidic acid phosphohydrolase, or cyclooxygenase.

Apoptosis in human embryo development: 2. Cerebellum.

We analysed the spatial and temporal distribution of apoptosis in human cerebellum development, during embryonic and fetal periods. Cerebella excised from two human embryos (8 weeks old) and eight fetuses (12-22 weeks old), were paraffin embedded and serially sectioned. Apoptotic cells were identified by propidium iodide staining, and TUNEL.

Neoductular progenitor cells regenerate hepatocytes in severely damaged liver: a comparative ultrastructural study.

In severely injured liver, stem cells give rise to progeny that tend to replace lost hepatocytes. Neoductular reaction appears as an inherent stage of liver reconstruction following severe damage caused by different pathological mechanisms. Few ultrastructural types of progenitor cells have been described, and some molecular phenotypes of progenitor stages have been characterized, but the details of the differentiation process are largely unknown.

Ultrastructural localization of Ca2+ in the Golgi apparatus of two different cell types.

The precipitation reaction with potassium oxalate was used to investigate the subcellular localization of Ca2+ in atrial myocardocytes and in Schwann cells of non-myelinated nerve fibers. Chelation with EGTA was used to prove the presence of Ca2+ in the electronoopaque deposits. In both cell types the oxalate reaction was intense in the classically described Ca2+ deposits: the perinuclear cisterna, the endo (sarco) plasmic reticulum, the mitochondrial matrix, but also in a novel localization: the cisternae of the Golgi stack in all cis to trans positions, suggesting that Golgi Apparatus is a major intracellular Ca2+ pool.

Cholinergic innervation of the ventricular myocardium in the human fetal heart.

Specimens of human fetal hearts from the 9th to the 27th week of intrauterine life were processed by the technique of Karnowski and Roots as modified by Lewis for the demonstration of acetylcholinesterase-positive nerve fibers by light microscopy. Cholinergic innervation was present in both atria and ventricles even in the 9th week of intrauterine life. In the ventricles the number of cholinergic fibers augmented with increasing age; they spread in the ventricular wall surrounding the vascular network including capillaries, or following their course in the close proximity of cardiac muscle fibers.

Antibodies against phospholipase C inhibit smooth muscle contraction induced by acetylcholine and histamine.

The rationale of this study was to obtain a highly specific inhibitor of phospholipase C by raising rabbit antibodies against the purified bacterial phospholipase C. The antibodies inhibited the enzyme activity in vitro and, as shown by immunofluorescence, cross-reacted with the membrane-bound phospholipase C of isolated guinea-pig smooth muscle cells. Incubation (0-4 h) of guinea-pig taenia coli and ileum with antibodies resulted in a progressive inhibition (up to 85%) of the contractile response evoked by 2 microM acetylcholine or 2 microM histamine but did not inhibit significantly the contraction produced by prostaglandin F2 alpha (0.

An equivalent of the paraventricular organ in the human fetus.

Serial sections of the hypophyseal-hypothalamic region processed by the Golgi-Cox and hematoxylin-eosin staining methods show features of the third ventricular wall which suggest the existence in the human fetus of an equivalent of the paraventricular organ, described in other species. In a 28 cm vertex-coccis long human fetus, there is a caudal extension of the infundibular recess that extends into the neural lobe of the hypophysis. This extension takes the shape of successive dilatations intercommunicating by narrow channels, lined by a thicker ventricular ependyma.

The mediobasal hypothalamus in the human fetus. Studies on neurovascular link by Golgy-Cox technique.

There is a remarkable parallel between the development and maturation of the nervous cells and that of the vascular elements in the human fetus. By the Golgy method the hypophysiotrophic area appears to be uniformly populated by small multipolar neurons within the loops of the primary capillary plexus. Only in the 80 mm embryo did we find bipolar neurons, whose processes are directed to the 3rd ventricle and respectively to the median eminence (ME).