Overcoming Lead Penetration Failure in Left Bundle Branch Area Pacing.

Left bundle branch area pacing is an innovative technique employed to maintain left ventricular synchrony. However, the operator can face challenges in penetrating the lead into the septum during screwing. Two pitfalls-helix-only penetration and shallow penetration-hinder lead penetration.

Chemical basis of prey recognition in thamnophiine snakes: the unexpected new roles of parvalbumins.

Detecting and locating prey are key to predatory success within trophic chains. Predators use various signals through specialized visual, olfactory, auditory or tactile sensory systems to pinpoint their prey. Snakes chemically sense their prey through a highly developed auxiliary olfactory sense organ, the vomeronasal organ (VNO).

In vitro biomedical applications of functionalized iron oxide nanoparticles, including those not related to magnetic properties.

Superparamagnetic iron oxide nanoparticles (SPION) are very promising contrast media, especially for molecular imaging, due to their superior NMR efficacy. They even have wider biomedical applications such as in drug and gene delivery, tissue engineering and bioseparation, or as sensitive biological nanosensors. By coupling them to affinity ligands, SPION can bind to drugs, proteins, enzymes, antibodies or nucleotides.

Monoclonal antibody to CD31 (PECAM-1) inhibits tubular regeneration after ischemia reperfusion injury in the rat.

Aims: We used a rat model of renal ischemia (35 min) to test the potential involvement of platelet/endothelial cell adhesion molecule 1 (PECAM-1/CD31) in the process of S3 tubule regeneration.

Methods: A monoclonal antibody specific for murine PECAM-1 was injected i.p.

Immunohistochemical localization of galectins-1 and -3 and monitoring of tissue galectin-binding sites during tubular regeneration after renal ischemia reperfusion in the rat.

Endogenous lectins act as effectors of cellular activities such as growth regulation, migration and adhesion. In this study, we report the histochemical detection of galectins and their binding sites in rat kidneys after ischemic injury (35 min) with regard to renal regeneration. In this context, we have shown in a previous publication (Vansthertem et al.

Expression of nestin, vimentin, and NCAM by renal interstitial cells after ischemic tubular injury.

This work explores the distribution of various markers expressed by interstitial cells in rat kidneys after ischemic injury (35 minutes) during regeneration of S3 tubules of outer stripe of outer medulla (OSOM). Groups of experimental animals (n = 4) were sacrificed every two hours during the first 24 hours post-ischemia as well as 2, 3, 7, 14 days post-ischemia. The occurrence of lineage markers was analyzed on kidney sections by immunohistochemistry and morphometry during the process of tubular regeneration.

Magnetic resonance molecular imaging of vascular cell adhesion molecule-1 expression in inflammatory lesions using a peptide-vectorized paramagnetic imaging probe.

The vascular cell adhesion molecule-1 (VCAM-1) has distinct roles in inflammatory cell recruitment to the damaged vessel wall. In the present work, a cyclic heptapeptide phage displayed library was screened in vitro during four rounds of biopanning. On the basis of Kd and IC50 values, a peptide (encoded as R832) was selected for in vitro and in vivo validation.

Potential amyloid plaque-specific peptides for the diagnosis of Alzheimer's disease.

Amyloid plaques (AP) represent one of the main molecular hallmarks of Alzheimer's disease (AD). In order to develop new AP-specific contrast agents for AD molecular imaging, the phage display technology was used to identify peptides specific to amyloid-beta (A beta(42)). A random disulfide constrained heptapeptide phage display library was screened against A beta(42).

Label-retaining cells and tubular regeneration in postischaemic kidney.

Background: In this study, we have examined rat kidneys after ischaemic injury (35 min) with regard to the dynamics of S3 tubule regeneration.

Methods: One day before ischaemia, each rat received four successive i.p.

Galectin-3 upregulation during tumor progression in head and neck cancer.

Objectives/hypothesis: To examine the level of expression of galectin-3 in relation to neoplastic progression of hypopharyngeal squamous cell carcinomas (HSCCs) and laryngeal squamous cell carcinomas (LSCCs).

Study Design: Retrospective study.

Methods: Using a polyclonal antibody against galectin-3 without cross-reactivity to other galectins, we analyzed the presence of galectin-3 using quantitative immunohistochemistry in i) a series of 79 HSCCs compared with 16 normal epithelia, 20 low-grade dysplasia (Low_D) and 25 high-grade dysplasia (High_D) and in ii) a series of 58 LSCCs compared with 34 normal epithelia, 12 Low_D, and 18 High_D.

Increased expression and altered intracellular distribution of adhesion/growth-regulatory lectins galectins-1 and -7 during tumour progression in hypopharyngeal and laryngeal squamous cell carcinomas.

Aims: To examine the level of expression of the pleiotropic regulators galectins-1 and -7 in relation to neoplastic progression of hypopharyngeal (HSCCs) and laryngeal (LSCCs) squamous cell carcinomas.

Methods And Results: The presence of galectins-1 and -7 was investigated using quantitative immunohistochemistry in (i) a series of 78 HSCCs by comparison with 17 normal epithelia (N_E), 26 low-grade dysplasia (low_D) and 27 high-grade dysplasia (high_D) and (ii) a series of 56 LSCCs by comparison with 50 N_E, 23 low_D and 29 high_D. Galectin-1 positivity expressed as a percentage of cells was significantly higher in carcinomas (HSCCs and LSCCs) than in N_E, low_D or high_D (P < 10(-6)).

Molecular imaging of alpha v beta3 integrin expression in atherosclerotic plaques with a mimetic of RGD peptide grafted to Gd-DTPA.

Aims: The integrin alpha v beta3 is highly expressed in atherosclerotic plaques by medial and intimal smooth muscle cells and by endothelial cells of angiogenic microvessels. In this study, we have assessed non-invasive molecular magnetic resonance imaging (MRI) of plaque-associated alpha v beta3 integrin expression on transgenic ApoE-/- mice with a low molecular weight peptidomimetic of Arg-Gly-Asp (mimRGD) grafted to gadolinium diethylenetriaminepentaacetate (Gd-DTPA-g-mimRGD). The analogous compound Eu-DTPA-g-mimRGD was employed for an in vivo competition experiment and to confirm the molecular targeting.

High level of galectin-1 expression is a negative prognostic predictor of recurrence in laryngeal squamous cell carcinomas.

Monitoring of gene-expression profiles is assumed to refine tumor characterization of laryngeal squamous cell carcinomas (LSCCs) with a therapeutic perspective. This is especially expected for adhesion/growth-regulatory effectors such as galectins, a class of endogenous lectins. Using computer-assisted microscopy, we investigated the prognostic value contributed by the quantitative determination of the immunohistochemical levels of expression of galectin-1, -3 and -7 in a series of 62 LSCCs including 42 low- and 20 high-stage LSCCs.

The determination of the levels of circulating galectin-1 and -3 in HNSCC patients could be used to monitor tumor progression and/or responses to therapy.

To evaluate galectin-1, -3 and -7 serum levels as diagnostic and/or prognostic markers for head and neck squamous cell carcinomas (HNSCCs). ELISA was employed to test sera from 102 patients with HNSCCs and from 38 healthy control volunteers for galectin-1, -3 and -7 serum levels. Serum galectin levels were assayed by ELISA and the levels of galectin expression in HNSCCs were determined by means of immunohistochemistry.

Galectins as modulators of tumor progression in head and neck squamous cell carcinomas.

Head and neck squamous cell carcinomas (HNSCCs) remain a significant cause of morbidity worldwide. Biological therapies able to induce and/or upregulate antitumor immune responses could represent a complementary approach to conventional treatments for patients with HNSCC because, despite advances in surgery, radiotherapy, and chemotherapy, the overall survival rates for these patients have not changed over recent decades. Galectins are involved in the control of cell proliferation, cell death, and cell migration and in the modulation of various functions of the immune system.

Identification and characterization of new protein chemoattractants in the frog skin secretome.

The vomeronasal organ is a chemosensory organ present in most vertebrates and involved in chemical communication. In the last decade, the deciphering of the signal transduction process of this organ has progressed. However, less is known about the vomeronasal organ ligands and their structure-function relationships.

Galectin 7 (p53-induced gene 1): a new prognostic predictor of recurrence and survival in stage IV hypopharyngeal cancer.

Background: Eighty percent of hypopharyngeal squamous cell carcinoma patients have advanced stages (III and IV) of the disease, and biological markers are required to predict high-risk head and neck squamous cell carcinoma patients in need of highly aggressive treatments after surgery to improve the survival rate. We analyzed the potential prognostic value of galectin 7 in a series of 81 stage IV hypopharyngeal SCCs because galectin 7 is an emerging marker involved in the epidermal development of pluristratified epithelia and in epidermal cell migration.

Methods: The immunohistochemical expression of galectin 7 was determined on a series of 81 stage IV hypopharyngeal SCCs and was compared with that of galectins 1 and 3.

Dynamics of hyaluronan, CD44, and inflammatory cells in the rat kidney after ischemia/reperfusion injury.

Ischemia/reperfusion (I/R) injury in the kidney involves hemodynamic and cellular dysfunctions as well as leukocyte infiltration. Functional recovery occurs via cell proliferation and/or migration. To determine the roles of hyaluronan (HA) and its main receptor CD44 in renal postischemic processes, we compared their localization and expression with that of neutrophils, macrophages, and PCNA-positive (regenerative) cells as characterized by immunohistochemistry, up to 28 days after I/R in uninephrectomized rats.

Early expression of the Helicase-Like Transcription Factor (HLTF/SMARCA3) in an experimental model of estrogen-induced renal carcinogenesis.

Background: The Helicase-Like Transcription Factor (HLTF/SMARCA3) belongs to the family of SWI/SNF proteins that use the energy of ATP hydrolysis to remodel chromatin in a variety of cellular processes. Several SWI/SNF genes are disrupted in cancer, suggesting a role of tumor suppressor. Similarly, the HLTF gene was recently found to be inactivated by hypermethylation in a number of advanced colon and gastric tumors.

Towards functional glycomics by localization of binding sites for tissue lectins: lectin histochemical reactivity for galectins during diethylstilbestrol-induced kidney tumorigenesis in male Syrian hamster.

Endogenous lectins act as effectors of cellular activities such as growth regulation, migration, and adhesion. Following their immunohistochemical localization in our previous study (Saussez et al. in Histochem Cell Biol 123:29-41, 2005) we purified several galectins and used them as tools for monitoring accessible binding sites.

Differential regulation of angiotensin II receptors during renal injury and compensatory hypertrophy in the rat.

1. The renin-angiotensin system may be involved in the compensatory adaptations occurring after the reduction of renal mass and during the consecutive changes leading to chronic renal failure. We therefore investigated the regulation of angiotensin II receptors in two models of renal hypertrophy in the rat: hypertrophy following uninephrectomy (UNx) or subtotal nephrectomy (STNx).

Magnetic resonance imaging of inflammation with a specific selectin-targeted contrast agent.

E-selectin-targeted contrast enhancement of blood vessels in inflamed tissues was investigated with a new contrast agent, Gd-DTPA-B(sLe(x))A, which was recently obtained by grafting a synthetic mimetic of sialyl-Lewis(x), an E-selectin ligand, onto Gd-DTPA. The pharmacokinetics, biodistribution, and potential to image inflammation by MRI of this E-selectin-targeted contrast agent were evaluated. The inhibition (by 15-34%) produced by Gd-DTPA-B(sLe(x))A on Sialyl Le(x)-PAA-biotin binding to E-selectin confirmed the specific interaction of the new contrast agent with this adhesion molecule.

Toward functional glycomics by localization of tissue lectins: immunohistochemical galectin fingerprinting during diethylstilbestrol-induced kidney tumorigenesis in male Syrian hamster.

The current study focused on galectins (-1, -3, -4, -7, and -8) and deliberately performed immunohistochemical fingerprinting to explore their complexity in a context of experimental renal carcinogenesis. The diethylstilbestrol (DES)-induced renal tumors in male Syrian hamster kidney (SHKT) represent a unique animal model for the study of estrogen-dependent renal malignancies. Kidney sections of DES-treated hamsters (3 days to 11 months of DES exposure) were analyzed by immunohistochemistry using a panel of non-crossreactive antibodies raised against galectins-1, -3, -4, -7, and -8.

Ferritin-induced relaxation in tissues: an in vitro study.

Purpose: To study in vitro the proton relaxation induced in tissues by ferritin, the iron-storing protein of mammals.

Materials And Methods: Nuclear magnetic relaxation dispersion (NMRD) profiles of liver and spleen from control and iron-overloaded mice are compared with NMRD profiles of ferritin and Fercayl-a ferritin-like akaganeite particle-in aqueous solutions or in 1% agarose gel.

Results: The relaxation of water protons induced by ferritin and Fercayl in 1% agarose gel is comparable with the relaxation of aqueous solutions of the same compounds, but slower than the relaxation of liver and spleen.

Labyrinthectomy changes T-type calcium channels in vestibular neurones of the guinea pig.

In the vestibular nuclei of the awake guinea pig, all neurones are spontaneously active. After unilateral labyrinthectomy, this activity virtually disappears on the ipsilateral side, but is completely restored one week later. In a recent study, we observed that the restoration of spontaneous activity was correlated with an increase in pacemaker activity.