SK4 Ca2+ activated K+ channel is a critical player in cardiac pacemaker derived from human embryonic stem cells.

Proper expression and function of the cardiac pacemaker is a critical feature of heart physiology. Two main mechanisms have been proposed: (i) the "voltage-clock," where the hyperpolarization-activated funny current If causes diastolic depolarization that triggers action potential cycling; and (ii) the "Ca(2+) clock," where cyclical release of Ca(2+) from Ca(2+) stores depolarizes the membrane during diastole via activation of the Na(+)-Ca(2+) exchanger. Nonetheless, these mechanisms remain controversial.

A randomized cross-over study of inhalation of diesel exhaust, hematological indices, and endothelial markers in humans.

Background: Exposure to traffic-related air pollution (TRAP) is considered a trigger for acute cardiovascular events. Diesel Exhaust (DE) is a major contributor to TRAP in the world. We evaluated the effect of DE inhalation on circulating blood cell populations, hematological indices, and systemic inflammatory cytokines in humans using a specialized facility.

KCNQ1 channels do not undergo concerted but sequential gating transitions in both the absence and the presence of KCNE1 protein.

The co-assembly of KCNQ1 with KCNE1 produces I(KS), a K(+) current, crucial for the repolarization of the cardiac action potential. Mutations in these channel subunits lead to life-threatening cardiac arrhythmias. However, very little is known about the gating mechanisms underlying KCNQ1 channel activation.

Highly ordered large-scale neuronal networks of individual cells - toward single cell to 3D nanowire intracellular interfaces.

The use of artificial, prepatterned neuronal networks in vitro is a promising approach for studying the development and dynamics of small neural systems in order to understand the basic functionality of neurons and later on of the brain. The present work presents a high fidelity and robust procedure for controlling neuronal growth on substrates such as silicon wafers and glass, enabling us to obtain mature and durable neural networks of individual cells at designed geometries. It offers several advantages compared to other related techniques that have been reported in recent years mainly because of its high yield and reproducibility.

Multifaceted modulation of K+ channels by protein-tyrosine phosphatase ε tunes neuronal excitability.

Non-receptor-tyrosine kinases (protein-tyrosine kinases) and non-receptor tyrosine phosphatases (PTPs) have been implicated in the regulation of ion channels, neuronal excitability, and synaptic plasticity. We previously showed that protein-tyrosine kinases such as Src kinase and PTPs such as PTPα and PTPε modulate the activity of delayed-rectifier K(+) channels (I(K)). Here we show cultured cortical neurons from PTPε knock-out (EKO) mice to exhibit increased excitability when compared with wild type (WT) mice, with larger spike discharge frequency, enhanced fast after-hyperpolarization, increased after-depolarization, and reduced spike width.

The changing histological pattern of gastric polyps in an ethnically heterogeneous population.

Background And Aim: Variation in the prevalence of various types of gastric polyps worldwide may reflect different etiologies. Here, the authors report the dynamic changes in histological distribution of gastric polyps over time and by ethnicity for individuals who underwent gastroscopies between 1994 and 2009 at two hospitals in Jerusalem, Israel. During this time period, the proportion of patients receiving proton pump inhibitors (PPIs) increased while the proportion of patients infected with Helicobacter pylori (H.

ZnT-1 enhances the activity and surface expression of T-type calcium channels through activation of Ras-ERK signaling.

Zinc transporter-1 (ZnT-1) is a putative zinc transporter that confers cellular resistance from zinc toxicity. In addition, ZnT-1 has important regulatory functions, including inhibition of L-type calcium channels and activation of Raf-1 kinase. Here we studied the effects of ZnT-1 on the expression and function of T-type calcium channels.

Endogenous endophthalmitis with an unusual infective agent: Actinomyces neuii.

Purpose: To report an unusual case of a patient with endogenous endophthalmitis caused by Actinomyces neuii.

Methods And Results: A 69-year-old woman in an immunosuppressed state and who had a previous history of periappendicular abscess presented with bilateral red painful eyes. The diagnosis was confirmed by culture and pan-bacterial polymerase chain reaction drawn from anterior chamber sample.

[Unusual infection--Pasteurella canis bacteremia in a child after exposure to rabbit secretions].

Pasteurella spp. is a natural habitant of the oral flora and digestive tract of various domestic animals. There are several species of Pasteurella which can cause disease in humans.

Targeting the voltage sensor of Kv7.2 voltage-gated K+ channels with a new gating-modifier.

The pore and gate regions of voltage-gated cation channels have been often targeted with drugs acting as channel modulators. In contrast, the voltage-sensing domain (VSD) was practically not exploited for therapeutic purposes, although it is the target of various toxins. We recently designed unique diphenylamine carboxylates that are powerful Kv7.

Effect of diesel exhaust inhalation on antioxidant and oxidative stress responses in adults with metabolic syndrome.

Background: Traffic-related air pollution is associated with cardiovascular morbidity and mortality. Although the biological mechanisms are not well understood, oxidative stress may be a primary pathway. Subpopulations, such as individuals with metabolic syndrome (MeS), may be at increased risk of adverse effects associated with air pollution.

Intracellular domains interactions and gated motions of I(KS) potassium channel subunits.

Voltage-gated K(+) channels co-assemble with auxiliary beta subunits to form macromolecular complexes. In heart, assembly of Kv7.1 pore-forming subunits with KCNE1 beta subunits generates the repolarizing K(+) current I(KS).

Protective effect of the immunomodulator AS101 against cyclophosphamide-induced testicular damage in mice.

Background: Cyclophosphamide (Cy), a widely used anticancer drug, is associated with significant testicular damage and sterility. Co-administration of the immunomodulating compound AS101 during chemotherapy treatments was previously shown to protect organs against cytotoxic damage, without attenuating the drug's anticancer effect. In this animal study, we investigated the effect of AS101 on testicular damage, sperm DNA damage and infertility induced by Cy.

Pleural plaques related to "take-home" exposure to asbestos: An international case series.

Context: While a large number of studies indicate the risks of high-level exposures to asbestos in the workplace setting, a relatively small number of studies describe the risk of pleural disease related to "take-home" asbestos brought into the household by workers exposed to asbestos. Consequently, the risk of pleural disease in family members of asbestos-exposed workers is likely underappreciated.

Case Presentations: Two families of siblings, one in Israel and one in the US, were evaluated because of their significant exposures to asbestos brought into the home by family members with heavy occupational exposures.

[The effectiveness of glass bead sterilizer in the dental practice].

Objectives: Although it is not FDA-approved as inter-patients sterilization measure, in Israel, glass bead sterilizer is still a common method for chair-side sterilization of small dental hand instruments, especially endodontic files. Studies from the 1950-1970s achieved sterilization by the bead sterilizer within few seconds. Nevertheless, there are no current evidence-based instructions for using this sterilizer.

Thrombotic markers in metabolic syndrome subjects exposed to diesel exhaust.

Traffic-derived particulate matter (PM) is associated with cardiovascular morbidity and mortality, but the mechanism of this association is unclear. Prothrombotic processes have been linked to PM in epidemiological and animal models, but have not been consistently implicated in controlled human models. Diesel exhaust (DE) is a major contributor to PM.

Diesel exhaust inhalation elicits acute vasoconstriction in vivo.

Background: Traffic-related air pollution is consistently associated with cardiovascular morbidity and mortality. Recent human and animal studies suggest that exposure to air pollutants affects vascular function. Diesel exhaust (DE) is a major source of traffic-related air pollution.

KCNE1 constrains the voltage sensor of Kv7.1 K+ channels.

Kv7 potassium channels whose mutations cause cardiovascular and neurological disorders are members of the superfamily of voltage-gated K(+) channels, comprising a central pore enclosed by four voltage-sensing domains (VSDs) and sharing a homologous S4 sensor sequence. The Kv7.1 pore-forming subunit can interact with various KCNE auxiliary subunits to form K(+) channels with very different gating behaviors.

S1 constrains S4 in the voltage sensor domain of Kv7.1 K+ channels.

Voltage-gated K(+) channels comprise a central pore enclosed by four voltage-sensing domains (VSDs). While movement of the S4 helix is known to couple to channel gate opening and closing, the nature of S4 motion is unclear. Here, we substituted S4 residues of Kv7.

Effects of diesel exhaust inhalation on heart rate variability in human volunteers.

Objectives: Particulate matter (PM) air pollution is associated with alterations in cardiac conductance and sudden cardiac death in epidemiological studies. Traffic-related air pollutants, including diesel exhaust (DE) may be at least partly responsible for these effects. In this experimental study we assessed whether short-term exposure to DE would result in alterations in heart rate variability (HRV), a non-invasive measure of autonomic control of the heart.