Absence epilepsy in apathetic, a spontaneous mutant mouse lacking the h channel subunit, HCN2.

Analysis of naturally occurring mutations that cause seizures in rodents has advanced understanding of the molecular mechanisms underlying epilepsy. Abnormalities of I(h) and h channel expression have been found in many animal models of absence epilepsy. We characterized a novel spontaneous mutant mouse, apathetic (ap/ap), and identified the ap mutation as a 4 base pair insertion within the coding region of Hcn2, the gene encoding the h channel subunit 2 (HCN2).

Reproducibility and accuracy of body composition assessments in mice by dual energy x-ray absorptiometry and time domain nuclear magnetic resonance.

OBJECTIVE: To assess the accuracy and reproducibility of dual-energy absorptiometry (DXA; PIXImus(™)) and time domain nuclear magnetic resonance (TD-NMR; Bruker Optics) for the measurement of body composition of lean and obese mice. SUBJECTS AND MEASUREMENTS: Thirty lean and obese mice (body weight range 19-67 g) were studied. Coefficients of variation for repeated (x 4) DXA and NMR scans of mice were calculated to assess reproducibility.

Functional consequences of the human leptin receptor (LEPR) Q223R transversion.

Perturbations in the functional integrity of the leptin axis are obvious candidates for mediation of altered adiposity. In a large number of genetic association studies in humans, the nonconservative LEPR Q223R allele has been inconsistently associated with adiposity. Subtle, long-term effects of such genetic variants can be obscured by effects of the environment and other confounders that render definitive inferences difficult to reach.

Oligonucleotide array CGH studies in myeloproliferative neoplasms: comparison with JAK2V617F mutational status and conventional chromosome analysis.

Comparative genomic hybridization (CGH), using oligo arrays with either 44,000 or 105,000 oligonucleotides, was performed on granulocyte-derived DNA from 71 patients with BCR-ABL-negative classic myeloproliferative neoplasms (MPNs): 32 primary myelofibrosis (PMF), 26 polycythemia vera (PV) and 13 essential thrombocythemia (ET). Copy number changes (CNCs) were detected in 44%, 35%, and 15% of the cases with PMF, PV and ET, respectively. In ET and PMF, CNCs were more frequently detected in the presence of JAK2V617F (50% vs.

Positional cloning of "Lisch-Like", a candidate modifier of susceptibility to type 2 diabetes in mice.

In 404 Lep(ob/ob) F2 progeny of a C57BL/6J (B6) x DBA/2J (DBA) intercross, we mapped a DBA-related quantitative trait locus (QTL) to distal Chr1 at 169.6 Mb, centered about D1Mit110, for diabetes-related phenotypes that included blood glucose, HbA1c, and pancreatic islet histology. The interval was refined to 1.

Coordination of Kinesin motors pulling on fluid membranes.

Intracellular transport relies on the action of motor proteins, which work collectively to either carry small vesicles or pull membranes tubes along cytoskeletal filaments. Although the individual properties of kinesin-1 motors have been extensively studied, little is known on how several motors coordinate their action and spatially organize on the microtubule when pulling on fluid membranes. Here we address these questions by studying, both experimentally and numerically, the growth of membrane tubes pulled by molecular motors.

Regulation of Fto/Ftm gene expression in mice and humans.

Two recent, large whole-genome association studies (GWAS) in European populations have associated a approximately 47-kb region that contains part of the FTO gene with high body mass index (BMI). The functions of FTO and adjacent FTM in human biology are not clear. We examined expression of these genes in organs of mice segregating for monogenic obesity mutations, exposed to underfeeding/overfeeding, and to 4 degrees C.

Detection of fractional steps in cargo movement by the collective operation of kinesin-1 motors.

The stepping behavior of single kinesin-1 motor proteins has been studied in great detail. However, in cells, these motors often do not work alone but rather function in small groups when they transport cellular cargo. Until now, the cooperative interactions between motors in such groups were poorly understood.

Prevalence of diabetes mellitus and its complications in a population-based sample in Al Ain, United Arab Emirates.

Aims: To determine the prevalence of diabetes mellitus (DM) and its complications in the adult population of the United Arab Emirates (UAE) and assess the degree of metabolic control in subjects with diagnosed DM.

Methods: A random sample of houses of Emirati citizens living in Al Ain, UAE was surveyed. Fasting blood glucose was determined by glucose meter and an oral glucose tolerance test (OGTT) was conducted if blood sugar was <7 mmol/l.

Selected plant species from the Cree pharmacopoeia of northern Quebec possess anti-diabetic potential.

Type II diabetes is a major health problem worldwide. Some populations, such as aboriginal peoples, are particularly at risk for this disease. In the Cree Nation of Quebec, Canada, prevalence in adults is approaching 20%, and the consequences are compounded by low compliance with modern medicine.

Anti-diabetic properties of the Canadian lowbush blueberry Vaccinium angustifolium Ait.

Incidence of type II diabetes is rapidly increasing worldwide. In order to identify complementary or alternative approaches to existing medications, we studied anti-diabetic properties of Vaccinium angustifolium Ait., a natural health product recommended for diabetes treatment in Canada.

p14ARF activates a Tip60-dependent and p53-independent ATM/ATR/CHK pathway in response to genotoxic stress.

p14ARF is a tumor suppressor that controls a well-described p53/Mdm2-dependent checkpoint in response to oncogenic signals. Here, new insights into the tumor-suppressive function of p14ARF are provided. We previously showed that p14ARF can induce a p53-independent G2 cell cycle arrest.

p14ARF promotes RB accumulation through inhibition of its Tip60-dependent acetylation.

p14ARF is a tumour suppressor which plays a critical role in p53-dependent or -independent cell growth control. Several studies have recently provided evidence that p14ARF can also interfere either directly or indirectly with some components of the RB signalling pathway to mediate its antiproliferative activity. The aim of this study was to explore the existence of direct relationships between p14ARF and RB proteins.

Plants used by the Cree Nation of Eeyou Istchee (Quebec, Canada) for the treatment of diabetes: A novel approach in quantitative ethnobotany.

In the last decade, the Cree Nation of Eeyou Istchee has witnessed a 150% increase in the prevalence of Type II Diabetes (T2D) for people aged over 20 years. Clinical intervention using conventional therapeutic methods has yielded only a limited success within this population. An ethnobotanical survey was carried out to identify potentially antidiabetic plant species used within the traditional pharmacopoeia of the Cree.

Synthesis and preliminary physical applications of a rhodamin-biotin phosphatidylethanolamine, an easy attainable lipid double probe.

In route to a physical study aimed at understanding lipids and proteins sorting in cells, we designed a rhodamin-labelled biotinylated phosphatidylethanolamine (PE), as a useful and easy-attainable lipid double probe. The target compound was successfully engaged in preliminary physical experiments.

Cooperative extraction of membrane nanotubes by molecular motors.

In eukaryotic cells, nanotubes represent a substantial fraction of transport intermediates between organelles. They are extracted from membranes by molecular motors walking along microtubules. We previously showed that kinesins fixed on giant unilamellar vesicles in contact with microtubules are sufficient to form nanotubes in vitro.

[Advantages of the in vivo HRT2 corneal confocal microscope for investigation of the ocular surface epithelia].

Purpose: To show the advantages of the in vivo HRT2 confocal microscope corneal module for studying the superficial and peripheral corneal and conjunctival epithelia.

Material And Methods: We examined 15 patients whose superficial cornea was healthy and ten patients with keratoconjunctivitis sicca and/or rosacea. Some conjunctival imprints where taken on patients with superficial ocular disease and examined by immunofluorescence.

High-quality animation of 2D steady vector fields.

Simulators for dynamic systems are now widely used in various application areas and raise the need for effective and accurate flow visualization techniques. Animation allows us to depict direction, orientation, and velocity of a vector field accurately. This paper extends a former proposal for a new approach to produce perfectly cyclic and variable-speed animations for 2D steady vector fields (see [1] and [2]).

Contralateral effect of amitriptyline and bupivacaine for sciatic nerve block in an animal model of inflammation.

Background: Using a carrageenan inflammation rat model, we evaluated two experimental approaches to prolong sciatic nerve block on contralateral hyperalgesia. Method. We performed ipsilateral sciatic nerve block on the inflamed hind paw with bupivacaine-loaded microspheres suspended in dexamethasone (bupivacaine 12.

Alloantibody production is regulated by CD4+ T cells' alloreactive pathway, rather than precursor frequency or Th1/Th2 differentiation.

Although CD4(+) T cells play an important role in the regulation of allograft rejection, the exact mechanisms by which they operate and the actual contribution of direct and indirect alloreactivity pathways remain to be fully characterized. Previous studies have established a possible relationship between the indirect alloreactivity pathway and antibody production, but interpretation of these results have been complicated by shortcomings inherent to the models used in these studies. To address this issue, we have developed a model based on TCR transgenic mice derived from a CD4(+) T-cell clone which recognize specific alloantigens by both alloreactivity pathways.

Natural alkylglycerols restrain growth and metastasis of grafted tumors in mice.

Alkylglycerols are natural etherlipids abundant in shark liver oil (SLO) in a diacylated form. SLO is known to have antitumor properties and was recently described as an inhibitor of tumor neovascularization. However, most studies did not discriminate between the respective activities of alkylglycerols and of fatty acids, which both have potent biological properties.

p14ARF induces G2 arrest and apoptosis independently of p53 leading to regression of tumours established in nude mice.

Until recently, the ability of ARF (human p14(ARF), murine p19(ARF)) tumour-suppressor protein, encoded by the INK4A/ARF locus, to inhibit cell growth in response to various stimuli was related to its ability to stabilize p53 through the so-called ARF/MDM2/p53 pathway. However, recent data have demonstrated that ARF is not implicated in this unique p53-dependent pathway. By use of transient and stable expression, we show here that human p14(ARF) inhibits the growth of human tumoral cells lacking functional p53 by inducing a transient G(2) arrest and subsequently apoptosis.

The mouse mahoganoid coat color mutation disrupts a novel C3HC4 RING domain protein.

The mouse coat color mutant mahoganoid (md) darkens coat color and decreases the obesity of A(y) mice that ectopically overexpress agouti-signaling protein. The phenotypic effects of md are similar to those of the recently identified coat color mutant mahogany (Atrn(mg)). We report the positional cloning of mahoganoid, encoding a novel 494-amino acid protein containing a C3HC4 RING (really interesting new gene) domain that may function as an E3 ubiquitin ligase.