Effects of seining effort on estimates of fish diversity in a sand-bed river.

Changes in species diversity can be an indicator of ecosystem disturbance, impairment, or recovery. Estimating sampling effort needed to adequately represent stream fish assemblages is necessary for informing conservation actions. Increased sampling intensity can increase species detection, affecting the accuracy and precision of biodiversity indices.

Estimation of left behind subway passengers through archived data and video image processing.

Crowding is one of the most common problems for public transportation systems worldwide, and extreme crowding can lead to passengers being left behind when they are unable to board the first arriving bus or train. This paper combines existing data sources with an emerging technology for object detection to estimate the number of passengers that are left behind on subway platforms. The methodology proposed in this study has been developed and applied to the subway in Boston, Massachusetts.

Coronaridine congeners potentiate GABA receptors and induce sedative activity in mice in a benzodiazepine-insensitive manner.

To determine whether (+)-catharanthine induces sedative- or anxiolytic/anxiogenic-like activity in male mice, proper animal paradigms were used. The results showed that (+)-catharanthine induces sedative-like activity in the 63-72 mg/Kg dose range in a flumazenil-insensitive manner, but neither this effect nor anxiolytic/anxiogenic-like activity was observed at lower doses. To determine the underlying molecular mechanism of the sedative-like activity, electrophysiological and radioligand binding experiments were performed with (+)-catharanthine and (±)-18-methoxycoronaridine [(±)-18-MC] on GABA (GABARs) and glycine receptors (GlyRs).

Creatine, Creatine Kinase, and Aging.

With an ever aging population, identifying interventions that can alleviate age-related functional declines has become increasingly important. Dietary supplements have taken center stage based on various health claims and have become a multi-million dollar business. One such supplement is creatine, a major contributor to normal cellular physiology.

Identification of a unique Ca-binding site in rat acid-sensing ion channel 3.

Acid-sensing ion channels (ASICs) evolved to sense changes in extracellular acidity with the divalent cation calcium (Ca) as an allosteric modulator and channel blocker. The channel-blocking activity is most apparent in ASIC3, as removing Ca results in channel opening, with the site's location remaining unresolved. Here we show that a ring of rat ASIC3 (rASIC3) glutamates (Glu435), located above the channel gate, modulates proton sensitivity and contributes to the formation of the elusive Ca block site.

Targeted Acid-Sensing Ion Channel Therapies for Migraine.

Acid-sensing ion channels (ASICs) are a family of ion channels, consisting of four members; ASIC1 to 4. These channels are sensitive to changes in pH and are expressed throughout the central and peripheral nervous systems-including brain, spinal cord, and sensory ganglia. They have been implicated in a number of neurological conditions such as stroke and cerebral ischemia, traumatic brain injury, and epilepsy, and more recently in migraine.

Effects of creatine supplementation on nociception in young male and female mice.

Background: The objective of this study was to evaluate creatine as an anti-nociceptive compound in an animal model of thermal and inflammatory pain. Creatine has the structural potential to interact with acid-sensing ion channels (ASIC), which have been involved in pain sensation modulation. The hypothesis evaluated in this study was that creatine will interact with ASICs leading to decreased nociception.

4-Chlorophenylguanidine is an ASIC3 agonist and positive allosteric modulator.

Acid-sensing ion channels (ASICs) are proton-sensitive sodium channels that open in response to lowered extracellular pH and are expressed in the central and peripheral nervous systems. The ASIC3 subtype is found primarily in the periphery where the channel mediates pain signals caused by ischemia and inflammation. Here, we provide identify 4-chlorophenylguanidine (4-CPG) as an ASIC3 positive allosteric modulator and newest member of the growing group of guanidine modulators of ASICs.

Acidity and Acid-Sensing Ion Channels in the Normal and Alzheimer's Disease Brain.

Alzheimer's disease prevalence has reached epidemic proportion with very few treatment options, which are associated with a multitude of side effects. A potential avenue of research for new therapies are protons, and their associated receptor: acid-sensing ion channels (ASIC). Protons are often overlooked neurotransmitters, and proton-gated currents have been identified in the brain.

5-(N, N-Hexamethylene) amiloride is a GABA-A ρ1 receptor positive allosteric modulator.

Guanidine compounds act as ion channel modulators. In the case of Cys-loop receptors, the guanidine compound amiloride antagonized the heteromeric GABA-A, glycine, and nicotinic acetylcholine receptors. However, amiloride exhibits characteristics consistent with a positive allosteric modulator for the human GABA-A (hGABA-A) ρ1 receptor.

Amiloride and GMQ Allosteric Modulation of the GABA-A ρ1 Receptor: Influences of the Intersubunit Site.

Amiloride, a diuretic used in the treatment of hypertension and congestive heart failure, and 2-guanidine-4-methylquinazoline (GMQ) are guanidine compounds that modulate acid-sensing ion channels. Both compounds have demonstrated affinity for a variety of membrane proteins, including members of the Cys-loop family of ligand-gated ion channels, such as the heteromeric GABA-A αβγ receptors. The actions of these guanidine compounds on the homomeric GABA-A ρ1 receptor remains unclear, especially in light of how many GABA-A αβγ receptor modulators have different effects in the GABA-A ρ1 receptors.

Oocyte zona pellucida dysmorphology is associated with diminished in-vitro fertilization success.

Background: Although irregularities in human zona pellucida (ZP) morphology are well described, there is scant literature on the clinical significance of ZP dysmorphology. We, therefore, designed a retrospective cohort trial of ZP dysmorphology to assess the clinical significance of ZP dysmorphology and its affect on IVF outcome. Over the same time period a random sample of 77 cycles of 77 subjects with all normal oocyte morphology were selected as controls.

A review of creatine supplementation in age-related diseases: more than a supplement for athletes.

Creatine is an endogenous compound synthesized from arginine, glycine and methionine. This dietary supplement can be acquired from food sources such as meat and fish, along with athlete supplement powders. Since the majority of creatine is stored in skeletal muscle, dietary creatine supplementation has traditionally been important for athletes and bodybuilders to increase the power, strength, and mass of the skeletal muscle.

Detergent screening of the human voltage-gated proton channel using fluorescence-detection size-exclusion chromatography.

The human voltage-gated proton channel (Hv1) is a membrane protein consisting of four transmembrane domains and intracellular amino- and carboxy-termini. The protein is activated by membrane depolarization, similar to other voltage-sensitive proteins. However, the Hv1 proton channel lacks a traditional ion pore.

Protons and Psalmotoxin-1 reveal nonproton ligand stimulatory sites in chicken acid-sensing ion channel: Implication for simultaneous modulation in ASICs.

Acid-sensing ion channels (ASICs) are proton-sensitive, sodium-selective channels expressed in the nervous system that sense changes in extracellular pH. These ion channels are sensitive to an increasing number of nonproton ligands that include natural venom peptides and guanidine compounds. In the case of chicken ASIC1, the spider toxin Psalmotoxin-1 (PcTx1) activates the channel, resulting in an inward current.

Positive Chlamydia trachomatis serology result in women seeking care for infertility is a negative prognosticator for intrauterine pregnancy.

Background: There are no prior studies that assess the non-in vitro fertilization (IVF) pregnancy rates in chlamydia serology-positive versus serology-negative women. Therefore, we wanted to determine whether a positive Chlamydia trachomatis immunoglobulin G serology result predicts reduced clinical pregnancy rates without IVF.

Methods: A prospective observational study was performed at a university-affiliated reproductive center.

Preimplantation genetic screening (PGS) with Comparative genomic hybridization (CGH) following day 3 single cell blastomere biopsy markedly improves IVF outcomes while lowering multiple pregnancies and miscarriages.

Purpose: To determine benefits of cleavage-stage preimplantation genetic screening (PGS) by array comparative genomic hybridization (CGH).

Methods: A retrospective case-control study was performed at a tertiary care university-affiliated medical center. Implantation rate was looked at as a primary outcome.

Effects of guided imagery on postoperative outcomes in patients undergoing same-day surgical procedures: a randomized, single-blind study.

The purpose of this investigation was to evaluate the effects of guided imagery on postoperative outcomes in patients undergoing same-day surgical procedures. Forty-four adults scheduled for head and neck procedures were randomly assigned into 2 groups for this single-blind investigation. Anxiety and baseline pain levels were documented preoperatively.

Defragmentation of low grade day 3 embryos resulted in sustained reduction in fragmentation, but did not improve compaction or blastulation rates.

In a prospective randomized fashion, this study evaluated embryo development in vitro after defragmentation versus assisted hatching alone of low grade day 3 embryos. Although a sustained decrease in day 5 fragmentation was observed in the defragmented group versus the assisted hatching only group, no difference in compaction rates or blastula formation rates were appreciated.

Pore architecture and ion sites in acid-sensing ion channels and P2X receptors.

Acid-sensing ion channels are proton-activated, sodium-selective channels composed of three subunits, and are members of the superfamily of epithelial sodium channels, mechanosensitive and FMRF-amide peptide-gated ion channels. These ubiquitous eukaryotic ion channels have essential roles in biological activities as diverse as sodium homeostasis, taste and pain. Despite their crucial roles in biology and their unusual trimeric subunit stoichiometry, there is little knowledge of the structural and chemical principles underlying their ion channel architecture and ion-binding sites.

Stoichiometric analysis of the TM2 6' phenylalanine mutation on desensitization in alpha1beta2 and alpha1beta2gamma2 GABA A receptors.

The presence of phenylalanine (F) at the 6' position of transmembrane domain 2 (TM2) in the alpha4 subunit of alpha4beta2 nicotinic receptors enhances desensitization. As the GABA A receptor affords the ability to study the influence of as few as one and as many as five Fs at this position, we have used it to investigate potential subunit- and stoichiometry-dependent effects of the TM2 6'F mutation on desensitization. Whereas the presence of one F at this position decreased extent of desensitization, desensitization was increased in all configurations that included two or more Fs at the TM2 6' position; desensitization was particularly rapid with 3 or 4 F residues present.

Structure of acid-sensing ion channel 1 at 1.9 A resolution and low pH.

Acid-sensing ion channels (ASICs) are voltage-independent, proton-activated receptors that belong to the epithelial sodium channel/degenerin family of ion channels and are implicated in perception of pain, ischaemic stroke, mechanosensation, learning and memory. Here we report the low-pH crystal structure of a chicken ASIC1 deletion mutant at 1.9 A resolution.

Brefeldin A and monensin inhibit the D quadrant organizer in the polychaete annelids Arctonoe vittata and Serpula columbiana.

The D quadrant organizer is a developmental signaling center that is localized to the vegetal D quadrant in different spiral-cleaving lophotrochozoan embryos and may be homologous to axial organizing regions in other metazoans. Patterning by this organizing center creates a secondary developmental axis and is required for the transition from spiral to bilateral cleavage and later establishment of the adult body plan. Organizer specification in equal-cleaving embryos is thought to involve inductive interactions between opposing animal and vegetal blastomeres.

Brefeldin A or monensin inhibits the 3D organizer in gastropod, polyplacophoran, and scaphopod molluscs.

In molluscs, the 3D vegetal blastomere acts as a developmental signaling center, or organizer, and is required to establish bilateral symmetry in the embryo. 3D is similar to organizing centers in other metazoans, but detailed comparisons are difficult, in part because its organizing function is poorly understood. To elucidate 3D function in a standardized fashion, we used monensin and brefeldin A (BFA) to rapidly and reversibly interfere with protein processing and secretion, thereby inhibiting the signaling interactions that underlie its specification and patterning.