Use of human remains detection dogs for wide area search after wildfire: a new experience for TexasTask Force 1 Search and Rescue resources.

In September 2011, wildfires in Bastrop County, TX, were the most destructive in the state's history, consuming more than 34000 acres (13759 hectares) and more than 1600 homes in the process. The wildfires began by consuming more than 30 homes across 2 miles (3.2 km) in 17 minutes, raising the fear that local residents may not have had sufficient time to escape the conflagration.

Regulation of transferrin-induced endocytosis by wild-type and C282Y-mutant HFE in transfected HeLa cells.

The hereditary hemochromatosis protein HFE is known to complex with the transferrin receptor; however, its function regarding endocytosis of transferrin is unclear. We performed patch-clamp capacitance measurements in transfected HeLa cells carrying wild-type or C282Y-mutant HFE cDNA under the control of a tetracycline-sensitive promoter. Whole cell experiments in cells with suppressed expression of wild-type HFE revealed a decrease in membrane capacitance, reflecting predominance of endocytosis in the presence of transferrin.

Slow infusion for the prevention of akathisia induced by prochlorperazine: a randomized controlled trial.

The utility of intravenous prochlorperazine (PCZ) in the treatment of nausea, vomiting, and headache may be limited by the akathisia that occurs frequently with the recommended 2-min infusion rate. We tested the hypothesis that decreasing the rate of PCZ infusion to 15 min reduces the incidence of akathisia at 1 hour. This double-blinded, randomized, controlled trial was conducted in the Emergency Department of an academic tertiary-care medical center with an annual census of 95,000 emergency patient visits.

Cations and anions as modifiers of ryanodine binding to the skeletal muscle calcium release channel.

Rate and equilibrium measurements of ryanodine binding to terminal cysternae fractions of heavy sarcoplasmic reticulum vesicles demonstrate that its activation by high concentrations of monovalent salts is based on neither elevated osmolarity nor ionic strength. The effect of the ions specifically depends on their chemical nature following the Hofmeister ion series for cations (Li+ < NH+4 < K- approximately Cs+ View Article and Find Full Text PDF

Microtubule-dependent transport of secretory vesicles visualized in real time with a GFP-tagged secretory protein.

Biosynthetic transport from the trans-Golgi network (TGN) to the plasma membrane (PM) is mediated by secretory vesicles. We analyzed secretory vesicle transport in real time using a GFP-tagged secretory protein, hCgB-GFP, consisting of human chromogranin B (hCgB) and green fluorescent protein (GFP). The fusion protein was expressed transiently in Vero cells or in a stable clone after induction with butyrate.

Modulation by monovalent anions of calcium and caffeine induced calcium release from heavy sarcoplasmic reticulum vesicles.

Both calcium and caffeine induced calcium release from actively loaded heavy sarcoplasmic reticulum vesicles were studied to analyze the dependence of both activities on the composition of the release medium with respect to monovalent anions. Calcium is unable to induce net calcium release while caffeine remains effective as releasing agent when the experimental media contain neither chloride nor nitrate ions. Caffeine induced calcium release is not suppressed by chelating residual medium calcium (approximately 0.

Modulation by ryanodine of active calcium loading and caffeine induced calcium release of heavy sarcoplasmic reticulum vesicles.

The effect of ATP on the calcium release channel in heavy sarcoplasmic reticulum vesicles modulated by ryanodine has been analyzed by monitoring active calcium uptake and caffeine induced calcium release under near physiological conditions. Native as well as ryanodine reacted vesicles display a complex time course of calcium uptake resulting in nearly complete exhaustion of medium calcium when ATP in combination with an ATP-regenerating system, in contrast to ATP alone, or dinitrophenyl phosphate, were used to support calcium uptake. Applying of dinitrophenyl phosphate as energy yielding substrate, not affecting channel activity, allowed to estimate the fraction of light vesicles devoided of calcium channels contaminating the heavy preparation as the fraction that stores calcium after the preparation has been treated with channel opening, low concentrations of ryanodine (1 microM).

How many ryanodine binding sites are involved in caffeine induced calcium release from sarcoplasmic reticulum terminal cysternae vesicles?

The inhibition by ryanodine of caffeine induced calcium release from actively loaded heavy sarcoplasmic vesicles has been studied in order to analyse the relation between the occupancy of the vesicular calcium release channels by ryanodine and channel function. Ryanodine binding was monitored with [3H]ryanodine under ionic conditions favouring the establishment of binding equilibrium. Binding follows 1:1 stoichiometry yielding dissociations constants between 7-12 nM and 12-15 pmol ryanodine/mg vesicular protein as maximum number of ryanodine binding sites.

Blockage of a pump-related calcium-efflux pathway in light sarcoplasmic reticulum vesicles by Mops.

Mops, used as a proton buffer, specifically enhances the accumulation of calcium or strontium by light sarcoplasmic reticulum vesicles driven by ATP or dinitrophenylphosphate as energy-yielding substrates when calcium-precipitating agents are absent. The enhancement of ion uptake by Mops is much greater for strontium than for calcium and is further increased when potassium is replaced by sodium as the dominant monovalent cation. Mops affects neither the activity of the calcium- or strontium-activated transport enzyme nor the active accumulation of calcium in the presence of oxalate, i.

The discrepancy between ryanodine binding and its effects on the calcium releasing system of the sarcoplasmic reticulum.

Heavy sarcoplasmic reticulum vesicles isolated from rabbit skeletal muscle were reacted in high ionic strength solutions with ryanodine. The effect of this reaction on ATP - and dinitrophenyl phosphate supported calcium uptake and caffeine induced calcium release were studied. At pH 7.

Interaction of ryanodine with the calcium releasing system of sarcoplasmic reticulum vesicles.

Heavy sarcoplasmic reticulum vesicles were reacted with ryanodine in 0.6 M KCl 0.3 M sucrose at pH 6.

Activation and inhibition of the calcium gate of sarcoplasmic reticulum by high-affinity ryanodine binding.

The occupancy of high-affinity ryanodine-binding sites of isolated heavy sarcoplasmic reticulum vesicles occurring in concentrated salt solutions affects ATP-dependent calcium accumulation and caffeine-induced calcium release. The initial suppression of calcium uptake is followed by a marked uptake activation resulting in a reduction of the final calcium level in the medium. Simultaneously, caffeine-induced calcium release is blocked.

Selective abolition of sarcoplasmic reticulum vesicles' calcium releasing mechanisms.

The ability of calcium loaded heavy sarcoplasmic reticulum vesicles to specifically respond to the addition of various agents such as caffeine, calcium ions and calmodulin antagonists to rapidly released calcium can largely be diminished by passing the vesicular suspension it 0.3 M sucrose, 0.6 M KCl, 4 mM CaCl2, pH 7.

Is the calcium pump involved in calcium release?

The blockage of all thiol residues accessible to the mercurial mersalyl in the sarcoplasmic reticulum membranes resulting in complete inactivation of the membranes' calcium transport system does interfere neither with caffeine- nor calcium-induced calcium release from actively loaded membrane vesicles.

Thyroxine induced transformation in sarcoplasmic reticulum of rabbit soleus and psoas muscles.

The properties of the sarcoplasmic reticulum membranes isolated from slow-twitch type I soleus and fast-twitch type II psoas muscles of control and thyroxine treated rabbits were comparatively studied. Membrane yield, maximal calcium storing capacity, ATP-supported calcium uptake, calcium-dependent ATPase activity and calcium-dependent phosphoprotein formation were found to be 3-10 fold higher in psoas than in soleus preparations. Membrane yield, calcium-dependent ATPase activity, ATP-supported calcium transport and calcium-dependent phosphoprotein are at least twice enhanced in the membranes from soleus muscles of animals treated for 14-21 days with thyroxine.

Invariance of stoichiometry of the sarcoplasmic reticulum calcium pump at physiological calcium concentrations--a reevaluation.

The decline of the transport ratio of the sarcoplasmic calcium pump observed in a recent study (A. Gafni and P. D.

Inhibitors of calmodulin-dependent phosphorylation simultaneously inhibit calcium uptake and calcium-dependent ATPase activity in skeletal muscle sarcoplasmic reticulum and transiently induce calcium release.

Under adequate experimental conditions calmodulin antagonists like compound 48/80 do not dissociate calcium uptake from the calcium-dependent ATP hydrolysis of skeletal muscle sarcoplasmic reticulum membranes but simultaneously inhibit both processes. Apart from the agent's pump inhibiting effect, they interact with the caffeine sensitive calcium channel in the sarcoplasmic reticulum causing a rapid transient calcium release.

A conformational transition of the sarcoplasmic reticulum calcium transport ATPase induced by vanadate.

Vanadate binding to sarcoplasmic reticulum vesicles results in the loss of the externally located high affinity calcium binding sites of the calcium transport ATPase. Conversely the occupation by calcium of the internally located low affinity sites in the vanadate enzyme complex leads to the release of vanadate. Since the total number of calcium binding sites is not diminished by vanadate binding but slightly increases we conclude that vanadate binding induces a transition of the enzymes external high to internal low affinity calcium binding sites.

Inactivation of the calcium-transport ATPase in the sarcoplasmic reticulum by the combined effect of lasolocid and Triton X-100.

The calcium-transport ATPase of the sarcoplasmic reticulum membranes is irreversibly inactivated by the combined action of Lasolocid and Triton X-100 at concentrations which separately do not interfere with the enzyme's activity. In the presence of Lasolocid the enzyme is most susceptible to inactivation when the Triton X-100 concentration just exceeds its critical micellar concentration, approximately, 0.2 mg X ml-1.

Inactivation of the sarcoplasmic reticulum calcium-transport-ATPase by Lasolocid in combination with Triton X-100.

The calcium-transport-ATPase of the sarcoplasmic reticulum membranes is irreversibly inactivated by the combined action of Lasolocid and Triton X-100 at concentrations which separately do not interfere with the enzyme's activity. In the presence of Lasolocid the enzyme is most susceptible to inactivation when the Triton X-100 concentration just exceeds its critical micellar concentration, approximately 0.2 mg .

Magnesium dependence of sarcoplasmic reticulum calcium transport.

The activity of the calcium transport systems in the sarcoplasmic reticulum membranes operating in the forward and reverse modes depends on the presence of magnesium ions. When the system operates as an NTP-driven calcium pump, magnesium enters the reaction chain chelated with NTP. Magnesium is a component of the NDP-sensitive phosphoprotein species involved in the NDP-NTP exchange reaction.

The inhibition of the calcium transport ATPase of the sarcomplasmic reticulum by fluorescamine: evidence for an oligomeric functional unit of the calcium transport system.

The labeling of the protein moiety of the sarcoplasmic calcium transport ATPase by fluorescamine suppresses calcium transport, calcium dependent ATPase activity, protein phosphorylation by [gamma-32P]ATP and [32P]phosphate at different extent of amino group substitution. For the hydrolysis of para nitrophenylphosphate by the calcium transport ATPase, it is shown that the relationship between the extent of amino group labelling can considerably be altered by the temperature and the presence of ethyleneglycol. It is shown that the amino residues of the phosphatidylethanolamine moiety do not contribute to the inhibiting effect of fluorescamine labelling.

Comparison between ATP-supported and GTP-supported phosphate turnover of the calcium-transporting sarcoplasmic reticulum membranes.

The study deals with the interrelationship of the phosphate-transferring activities of the calcium-transporting sarcoplasmic reticulum membrane vesicles: the phosphate exchange between nucleoside triphosphate (NTP) and nucleoside diphosphate (NDP) (NTP-NDP exchange), the calcium-dependent NTase, and the phosphorylation of NDP by inorganic phosphate in the presence of NTP (NTP-Pi exchange). Different nucleotides were used as phosphate donors and acceptors. It is demonstrated for the phosphate transfer from ITP to GDP that the NTP-NDP exchange exhibits ping-pong kinetics with Mg-ITP and unliganded GDP as substrates.

Calcium gradient dependent pyrophosphate formation by sarcoplasmic vesicles.

The vesicles of the sarcoplasmic membranes synthesize pyrophosphate from inorganic phosphate. Pyrophosphate synthesis proceeds as long as a calcium gradient is maintained across the vesicular membranes. Pyrophosphate synthesis is inhibited by low concentrations of nucleoside triphosphates.

Arrangement of proteins and lipids in the sarcoplasmic membrane.

The number of amino residues present in the proteins of the sarcoplasmic reticulum which can react with Fluram has been determined in native and sonicated SR vesicles. Sonication increases the number of amino groups accessible to Fluram from 0.57 to 0.