For aerobic and anaerobic growth experiments, all S oneidensis s

For aerobic and anaerobic growth experiments, all S. oneidensis strains were cultured in a defined salts medium (M1) supplemented with 20 mM lactate as carbon/energy source (Myers & Nealson, 1988). Vibrio parahaemolyticus and V. harveyi were tested for anaerobic metal reduction activity in marine broth (Difco) growth medium. Bacterial growth experiments were carried out in a B. Braun Biostat

B batch reactor with automatic feedback control of pH, temperature, and dissolved O2 concentration. Electron acceptors were synthesized as previously described (Saffarini et al., 1994; Blakeney et al., 2000; Taratus et al., 2000; Payne & DiChristina, see more 2006; Neal et al., 2007) and added at the following final concentrations: , 10 mM; , 2 mM; Fe(III) citrate, 50 mM; amorphous MnO2, 15 mM; trimethylamine-N-oxide (TMAO), 25 mM; , 10 mM; fumarate, 30 mM; and DMSO, 25 mM. Gentamycin was supplemented at 15 μg mL−1. PD98059 ic50 For the growth of E. coli β2155 λ pir, diaminopimelate was amended at 100 μg mL−1. Cell growth was monitored by direct cell counts via epifluorescence microscopy and by measuring terminal electron acceptor depletion or end product accumulation. Acridine

orange-stained cells were counted (Zeiss AxioImager Z1 Microscope) according to the previously described procedures (Burnes et al., 1998). Cell numbers at each time point were calculated as the average of 10 counts from two parallel yet independent anaerobic incubations. was measured spectrophotometrically with sulfanilic acid-N-1-naphthyl-ethylenediamine dihydrochloride solution (Montgomery & Dymock, 1962). Fe(III) reduction was monitored by measuring HCl-extractable Fe(II) production with ferrozine (Stookey, 1970). Mn(IV) concentration was Rapamycin cell line measured colorimetrically after reaction with benzidine hydrochloride as previously described (Burnes et al., 1998). Mn(III)-pyrophosphate concentration was measured colorimetrically as previously described (Kostka et al., 1995). concentrations were measured by cyanolysis as previously described

(Kelly & Wood, 1994). Growth on O2, TMAO, DMSO, and fumarate was monitored by measuring increases in cell density at 600 nm. Control experiments consisted of incubations with cells that were heat-killed at 80 °C for 30 min prior to inoculation. Genome sequence data for S. oneidensis MR-1, S. putrefaciens 200, S. putrefaciens CN32, S. putrefaciens W3-18-1, S. amazonensis SB2B, S. denitrificans OS217, S. baltica OS155, S. baltica OS195, S. baltica OS185, S. baltica OS223, S. frigidimarina NCIMB400, S. pealeana ATCC 700345, S. woodyi ATCC 51908, S. sp. ANA-3, S. sp. MR-4, S. sp. MR-7, S. loihica PV-4, S. halifaxens HAW-EB4, S. piezotolerans WP3, S. sediminis HAW-EB3, and S. benthica KT99 were obtained from the National Center for Biotechnology Information (NCBI, http://www.ncbi.nlm.nih.gov) or the Department of Energy Joint Genome Institute (DOE-JGI, http://jgi.doe.gov).

For aerobic and anaerobic growth experiments, all S oneidensis s

For aerobic and anaerobic growth experiments, all S. oneidensis strains were cultured in a defined salts medium (M1) supplemented with 20 mM lactate as carbon/energy source (Myers & Nealson, 1988). Vibrio parahaemolyticus and V. harveyi were tested for anaerobic metal reduction activity in marine broth (Difco) growth medium. Bacterial growth experiments were carried out in a B. Braun Biostat

B batch reactor with automatic feedback control of pH, temperature, and dissolved O2 concentration. Electron acceptors were synthesized as previously described (Saffarini et al., 1994; Blakeney et al., 2000; Taratus et al., 2000; Payne & DiChristina, MAPK inhibitor 2006; Neal et al., 2007) and added at the following final concentrations: , 10 mM; , 2 mM; Fe(III) citrate, 50 mM; amorphous MnO2, 15 mM; trimethylamine-N-oxide (TMAO), 25 mM; , 10 mM; fumarate, 30 mM; and DMSO, 25 mM. Gentamycin was supplemented at 15 μg mL−1. Dabrafenib ic50 For the growth of E. coli β2155 λ pir, diaminopimelate was amended at 100 μg mL−1. Cell growth was monitored by direct cell counts via epifluorescence microscopy and by measuring terminal electron acceptor depletion or end product accumulation. Acridine

orange-stained cells were counted (Zeiss AxioImager Z1 Microscope) according to the previously described procedures (Burnes et al., 1998). Cell numbers at each time point were calculated as the average of 10 counts from two parallel yet independent anaerobic incubations. was measured spectrophotometrically with sulfanilic acid-N-1-naphthyl-ethylenediamine dihydrochloride solution (Montgomery & Dymock, 1962). Fe(III) reduction was monitored by measuring HCl-extractable Fe(II) production with ferrozine (Stookey, 1970). Mn(IV) concentration was Tolmetin measured colorimetrically after reaction with benzidine hydrochloride as previously described (Burnes et al., 1998). Mn(III)-pyrophosphate concentration was measured colorimetrically as previously described (Kostka et al., 1995). concentrations were measured by cyanolysis as previously described

(Kelly & Wood, 1994). Growth on O2, TMAO, DMSO, and fumarate was monitored by measuring increases in cell density at 600 nm. Control experiments consisted of incubations with cells that were heat-killed at 80 °C for 30 min prior to inoculation. Genome sequence data for S. oneidensis MR-1, S. putrefaciens 200, S. putrefaciens CN32, S. putrefaciens W3-18-1, S. amazonensis SB2B, S. denitrificans OS217, S. baltica OS155, S. baltica OS195, S. baltica OS185, S. baltica OS223, S. frigidimarina NCIMB400, S. pealeana ATCC 700345, S. woodyi ATCC 51908, S. sp. ANA-3, S. sp. MR-4, S. sp. MR-7, S. loihica PV-4, S. halifaxens HAW-EB4, S. piezotolerans WP3, S. sediminis HAW-EB3, and S. benthica KT99 were obtained from the National Center for Biotechnology Information (NCBI, http://www.ncbi.nlm.nih.gov) or the Department of Energy Joint Genome Institute (DOE-JGI, http://jgi.doe.gov).

Urine and capillary ketone measurements, blood gas analysis and/o

Urine and capillary ketone measurements, blood gas analysis and/or venous bicarbonate measurement were analysed together with the clinical outcome of either admission or discharge of the patient. Selleck p38 MAPK inhibitor Capillary β-hydroxybutyrate measurement gave a strong negative correlation (r -0.771; p<0.001) with serum bicarbonate concentration. Urine ketone measurement showed a weaker negative correlation (r -0.493; p<0.001) with bicarbonate levels.

There was no difference in the ability to predict hospital admission between blood ketone measurement and urine ketone measurement )positive predictive value 84.6% [95% confidence interval 73.2–95.9%] vs positive predictive value 75.0% [95% confidence interval 62.2–87.8%], respectively). The findings of this study suggest that blood ketone measurement is a better predictor of acid base status than urine ketone measurement. Copyright © 2010 John Wiley & Sons. “
“Anaemia is often an unrecognised complication of diabetes that has an adverse effect on the progression

of diabetes related complications. Anaemia predicts mortality in diabetes related chronic kidney disease (CKD). Contributors to its development include absolute and/or functional iron deficiency and erythropoietin insufficiency. This study aimed to look at the prevalence of anaemia and markers of iron deficiency in patients with diabetes related CKD. An analysis was done of the results from all patients (225 men, 93 women; mean age 70 years) attending joint Dipeptidyl peptidase diabetes–renal clinics over a 12-month period. Haemoglobin (Hb) was measured in 88%. The mean Hb was 12.6g/dl in men and 11.7g/dl in women. A total of 21.5% www.selleckchem.com/products/Deforolimus.html (11.5% men, 10% women) had Hb <11g/dl who should have anaemia management as per National Institute for Health and Clinical Excellence guidelines. Among the anaemic population, CKD stage 3 was present in 25% of men and in 8% of women, with CKD stage 4 present in 20% of men and in 32% of women. Fifty-three percent had absolute iron deficiency (serum ferritin <100μg/L) and 41% had inadequate iron stores (serum ferritin between 100 and 500μg/L). Functional iron deficiency defined

by serum ferritin >100μg/L and red cell hypochromasia ≥6% was noted in 21.6% of anaemic patients. Anaemia is a frequent finding in patients with diabetes related CKD. A significant proportion of patients had functional iron deficiency that required iron therapy for optimisation of their iron stores before starting erythropoiesis-stimulating agents. Measurement of red cell hypochromasia is a valuable tool to detect this group of patients. Copyright © 2010 John Wiley & Sons. “
“The aims of this study were to translate the Michigan Diabetes Knowledge Test (MDKT) into the Malaysian language, and to examine the psychometric properties of the Malaysian version. A standard translation procedure was used to create the Malaysian version of the MDKT from the original English version.

Urine and capillary ketone measurements, blood gas analysis and/o

Urine and capillary ketone measurements, blood gas analysis and/or venous bicarbonate measurement were analysed together with the clinical outcome of either admission or discharge of the patient. GSK1120212 Capillary β-hydroxybutyrate measurement gave a strong negative correlation (r -0.771; p<0.001) with serum bicarbonate concentration. Urine ketone measurement showed a weaker negative correlation (r -0.493; p<0.001) with bicarbonate levels.

There was no difference in the ability to predict hospital admission between blood ketone measurement and urine ketone measurement )positive predictive value 84.6% [95% confidence interval 73.2–95.9%] vs positive predictive value 75.0% [95% confidence interval 62.2–87.8%], respectively). The findings of this study suggest that blood ketone measurement is a better predictor of acid base status than urine ketone measurement. Copyright © 2010 John Wiley & Sons. “
“Anaemia is often an unrecognised complication of diabetes that has an adverse effect on the progression

of diabetes related complications. Anaemia predicts mortality in diabetes related chronic kidney disease (CKD). Contributors to its development include absolute and/or functional iron deficiency and erythropoietin insufficiency. This study aimed to look at the prevalence of anaemia and markers of iron deficiency in patients with diabetes related CKD. An analysis was done of the results from all patients (225 men, 93 women; mean age 70 years) attending joint Thymidine kinase diabetes–renal clinics over a 12-month period. Haemoglobin (Hb) was measured in 88%. The mean Hb was 12.6g/dl in men and 11.7g/dl in women. A total of 21.5% buy IWR-1 (11.5% men, 10% women) had Hb <11g/dl who should have anaemia management as per National Institute for Health and Clinical Excellence guidelines. Among the anaemic population, CKD stage 3 was present in 25% of men and in 8% of women, with CKD stage 4 present in 20% of men and in 32% of women. Fifty-three percent had absolute iron deficiency (serum ferritin <100μg/L) and 41% had inadequate iron stores (serum ferritin between 100 and 500μg/L). Functional iron deficiency defined

by serum ferritin >100μg/L and red cell hypochromasia ≥6% was noted in 21.6% of anaemic patients. Anaemia is a frequent finding in patients with diabetes related CKD. A significant proportion of patients had functional iron deficiency that required iron therapy for optimisation of their iron stores before starting erythropoiesis-stimulating agents. Measurement of red cell hypochromasia is a valuable tool to detect this group of patients. Copyright © 2010 John Wiley & Sons. “
“The aims of this study were to translate the Michigan Diabetes Knowledge Test (MDKT) into the Malaysian language, and to examine the psychometric properties of the Malaysian version. A standard translation procedure was used to create the Malaysian version of the MDKT from the original English version.

The procedure is described as follows Cells were grown in ASSPL

The procedure is described as follows. Cells were grown in ASSPL to early log phase (OD600 nm of 0.15–0.2) and harvested by centrifugation. Harvested cells were washed twice with cold electroporation buffer (10% glycerol+1 mM MgCl2) and centrifuged at 4000 g for 10 min at 4 °C. The cell pellet was resuspended in the same electroporation buffer to 1/50 volume of the original culture. Eighty microliters of this cell suspension was mixed with 2 μg of genomic DNA or PCR amplicon on ice and transferred to a precooled 0.1-cm gap electroporation cuvette (BTX, Harvard Apparatus). The cell–DNA mixture was subjected to electroporation

at field Selleckchem INCB024360 strength of 20 kV cm−1, capacitance of 25 μF, and resistance of 200 Ω. Following electroporation, the cells were immediately diluted in 1 mL of THL medium and incubated anaerobically for 16 h at 37 °C then plated on THL agar plates

supplemented with 1 mg mL−1 streptomycin. Colonies would appear after 24–48 h. Using this protocol, we were able to consistently obtain 9–12 colonies μg−1 mutant genomic DNA, which was two to three times higher than the number of colonies from the wild-type DNA (3–5 colonies μg−1 DNA and these colonies are spontaneous mutants). This result suggested that at least half of the streptomycin-resistant colonies obtained using the mutant DNA contained introduced mutations while the rest may have originated from spontaneous mutation. We could not obtain consistent transformation results when using other parameter combinations mentioned in Materials and methods. selleckchem With the optimized protocol, we next tested whether PCR-generated DNA could be used to transform V. parvula PK1910. PCR amplicons were generated with the primers rpsLup-F and rpsLdn-R (Table 2 and Fig. 1) using the wild-type and the spontaneous streptomycin-resistant strains SR1 (AAG to AAC mutation) and SR2 (AAG to AAT mutation) as templates. The amplicons were named rpsL-WT, rpsL-SR1, and rpsL-SR2, respectively (Fig. 1). The three PCR amplicons were transformed into PK1910 Cell press with the procedure described above. In five

separate experiments, we obtained similar results as the transformation with genomic DNA: there were always about two times more colonies in the transformation with the mutant DNA than with the wild-type DNA. For one of these experiments, we sequenced the rpsL gene of all the colonies that appeared on the plates. As shown in Table 3, most colonies in the rpsL-SR1 transformation have AAC mutation in codon 43, while most colonies in the rpsL-SR2 transformation have AAT mutation in codon 43. The colonies in rpsL-WT transformation, representing the spontaneous mutation, have a similar distribution of the AAC or AAT mutation in codon 43. This result strongly suggests that DNA-mediated transformation had occurred in V.

Mutants H213A and D228A were obtained similarly by using the pair

Mutants H213A and D228A were obtained similarly by using the pair of primers NopT1-H213A-F/NopT1-H213A-R and NopT1-D228A-F/NopT1-D228A-R, which simultaneously introduced an EaeI and a PvuI restriction site, respectively. Mutants nopT1-DKM and nopT1-GCC were obtained by PCR amplification as described earlier using the pair of primers NopT1-DKM-F/NopT1-DKM-R and

NopT1-GCC-F/NopT1-GCC-R, respectively. The primers were designed to obtain the D47A, K48A, and M49A substitutions in case of the NopT1-DKM mutant and G50A, C52S, and C53S substitutions in case of the NopT1-GCC mutant. All mutations were confirmed by diagnostic restriction digestions taking advantage of SacII and NheI sites designed in the primers and sequencing. C-terminally polyhistidine-tagged wild-type NopT1 and NopT2, as well as mutant derivatives of NopT1, were obtained by cloning the respective

coding regions without the stop codons following PCR amplification from the pT7-7 expression Trametinib constructs with the pair of primers NopT1-F1/NopT1-R3 and NopT2-F1/NopT2-R3, respectively. The amplicons were digested with appropriate restriction enzymes MK-2206 and subcloned into the pET26b vector (Novagen), ligated, and transformed into E. coli strain BL21 (DE3). For protein expression, E. coli BL21 (DE3) transformants harboring the pET26b constructs were grown in LB medium to an OD600 nm of 0.6 at 37 °C, and protein expression was induced for 4 h at 30 °C by adding 0.5 mM isopropyl β-d-thiogalactopyranoside (IPTG). Bacterial cells were collected by centrifugation, ID-8 resuspended in lysis buffer (50 mM NaH2PO4, pH 8.0, 300 mM NaCl, 10 mM imidazole) supplemented with 1 mM phenylmethylsulfonyl fluoride (PMSF), and lysed by the addition of lysozyme followed by sonication. Histidine-tagged wild-type and mutant proteins were expressed in E. coli BL21 (DE3) at 30 °C and purified by Ni2+-NTA affinity chromatography under native conditions according to the standard protocol (Qiagen). Proteins were resolved in 14% SDS-polyacrylamide gel electrophoresis (PAGE) and were visualized by Coomassie blue staining and immunoblotting using alkaline phosphatase (AP)-conjugated

anti-His antibody (Qiagen). Protein concentrations were estimated by Coomassie blue staining of SDS-PAGE gels using BSA standards. Prestained molecular size standards (Broad range; New England Bio-Labs) were used to estimate the molecular mass of proteins. Proteins were purified under nondenaturing conditions as mentioned earlier and lyophilized, and their protease activity was determined using resorufin-labeled casein (Roche) as a substrate. Lyophilized samples were dissolved in different buffers at pH range 5.5–9.5 in final volume of 100 μL and preincubated at 37 °C for 1 h. The enzymatic activity was determined in 50 mM buffers (sodium acetate buffer at pH 5.5; potassium phosphate at pH range 6.5–7.5; Tris at pH range 8.5–9.5) containing 10 mM l-cysteine, 10 mM EDTA, and 0.4% casein in a final volume of 200 μL.

Thromboxane A2 is one of the cyclooxygenase products derived from

Thromboxane A2 is one of the cyclooxygenase products derived from arachidonic

acid, and acts on its cognate G protein-coupled receptor [thromboxane receptor (TP)]. We show here that TP in the striatum locally facilitates dopamine overflow. Intrastriatal injection of a TP agonist increased extracellular dopamine levels in the striatum as measured by in vivo microdialysis. TP stimulation also augmented electrically evoked dopamine overflow from striatal slices. Conversely, TP deficiency reduced dopamine overflow evoked by N-methyl-d-aspartic acid (NMDA) and acetylcholine in striatal slices. TP immunostaining showed that TP is enriched in vascular endothelial cells. Pharmacological blockade of nitric oxide (NO) synthesis and genetic deletion of endothelial NO synthase (eNOS) suppressed NMDA/acetylcholine-induced learn more dopamine Romidepsin order overflow. This involvement of NO was abolished in TP-deficient slices, suggesting a role for eNOS-derived NO synthesis in TP-mediated dopamine overflow. As a functional consequence of TP-mediated dopamine increase, a TP agonist suppressed GABAergic inhibitory postsynaptic currents in medium spiny neurons through a D2-like receptor-dependent mechanism. Finally, TP is involved in sucrose intake, a dopamine-dependent motivational behavior. These data suggest that TP stimulation in the striatum locally

facilitates dopamine overflow evoked by synaptic inputs via NO synthesis in endothelial cells. “
“Information processing in the vertebrate brain is thought to be mediated through distributed neural networks, but it is still unclear how sensory stimuli are encoded and detected by these networks, and what role synaptic inhibition Bay 11-7085 plays in this process. Here we used a collision avoidance behavior in Xenopus tadpoles as a model for stimulus discrimination and recognition. We showed that the visual system of the tadpole is selective for behaviorally relevant looming stimuli, and that the detection of these

stimuli first occurs in the optic tectum. By comparing visually guided behavior, optic nerve recordings, excitatory and inhibitory synaptic currents, and the spike output of tectal neurons, we showed that collision detection in the tadpole relies on the emergent properties of distributed recurrent networks within the tectum. We found that synaptic inhibition was temporally correlated with excitation, and did not actively sculpt stimulus selectivity, but rather it regulated the amount of integration between direct inputs from the retina and recurrent inputs from the tectum. Both pharmacological suppression and enhancement of synaptic inhibition disrupted emergent selectivity for looming stimuli. Taken together these findings suggested that, by regulating the amount of network activity, inhibition plays a critical role in maintaining selective sensitivity to behaviorally-relevant visual stimuli.

Sera were coagulated

Sera were coagulated EPZ-6438 mw overnight at 4 °C, and the clear supernatant was used for Western blotting. For this, cultures in 2 mL of M17 media were grown to an OD546 nm of 0.6–0.8, followed by induction for 90 min with either 20 μM to 3 mM CuSO4, 20 μM AgNO3 or CdSO4, 200 μM each of ZnSO4, FeSO4, NiCl2, CoCl2, nitrosoglutathione or H2O2, and 100 μM of 4-nitroquinoline-1-oxide. Cell lysates were prepared by centrifuging the cultures and treating the cell pellets with 50 μL of 10 mg mL−1 lysozyme, 1 mM EDTA and 10 mM Tris-Cl, pH 8, for 30 min at 37 °C. 10 μL of 1 mg mL−1 DNaseI in 100 mM MgCl2 was added and incubation was continued for 10 min at 25 °C. Cell debris was removed by centrifugation for 5 min at 12 000 g.

Protein concentrations in the supernatants were determined using the BioRad protein assay and 50 μg of protein resolved by electrophoresis on 12% SDS polyacrylamide

gels. Western blots were prepared as described previously (Towbin et al., 1979), using a horseradish peroxidase-coupled goat anti-rat IgG secondary antibody (Santa Cruz). Bands were visualized by chemiluminescence using 100 mM Tris-Cl, pH 8.5, 1.25 mM 3-aminophtalhydrazide, 0.2 mM p-coumaric acid and 0.01% H2O2. Chemiluminescence signals were captured using a Fuji LAS-1000 imaging system (Fuji Photo Film, Tokyo, Japan). The following commercial crystallization screens were used to look for initial crystallization conditions: Screen I and II (Hampton AZD0530 concentration Research), JCSG (Jena Bioscience) and PACT (Qiagen GmbH, Hilden, Germany). Flat-bottomed multi-subwell plates (Greiner, Langenthal, Switzerland) were used to set up sitting drop vapor-diffusion experiments by mixing 1 μL of 10 mg mL−1 YahD solution with 1 μL of screening solution and incubating at 18 °C. Initial conditions that yielded crystals were optimized by hanging drop vapor diffusion crystallization. Needle-shaped crystals were grown by mixing 1.5 μL of protein solution with 1 μL of well solution containing 37.5% polyethylene glycol 3350 and 150 mM of Na-dl-malate, pH 7.0. Crystals aminophylline grew to 50 μm in the longest direction within 3 weeks. For data collection, crystals were flash-frozen in liquid nitrogen

without the addition of a cryoprotectant. The crystals belonged to the orthorhombic space group P212121, with unit cell dimensions of a=40.67 Å, b=79.07 Å and c=130.03 Å. X-ray diffraction data were collected from a single crystal at beam line BL 14.1 at BESSY, Berlin, at 100 K and 0.918 Å wavelength. The data were integrated, reduced and scaled using XDS (Kabsch, 1993), resulting in a final data set that was fully complete at 1.88 Å resolution. A search model was built using the ccp4 suite program chainsaw (Stein, 2008), using the atomic coordinates of one monomer of the structure of the Bacillus cereus carboxylesterase (PDB accession 2HLI), which shares 32% amino acid identity with YahD. The sequence alignment of YahD to the B.

While the baseline EMG activity can explain a portion of the resp

While the baseline EMG activity can explain a portion of the response differential on pro- vs. anti-saccade in this timeframe (e.g. the last three stimulation points), our data show that a larger degree of interaction persists on anti-saccade vs. pro-saccade trials (histograms in Figs 5 and 6). How then can we reconcile larger evoked neck muscle responses on anti-saccade trials with the accompanying disruptions of anti-saccade AZD1152-HQPA concentration performance? We begin

by first considering the latency of the neck muscle response evoked by ICMS-SEF. As shown in Fig. 4A, the latency of the evoked neck muscle response is very short, beginning 25–30 ms after stimulation onset and peaking after the stimulation train. We have previously quantified Ku-0059436 research buy neck muscle response latencies to ICMS-SEF using a variety of methods to be in the range of 30 ms, leading any evoked saccades by ~40–70 ms on average (Chapman et al., 2012). The large difference between the onset latencies of neck muscle responses vs. saccades permits the use of short-duration stimulation as a probe of the excitability of the oculomotor system (Corneil et al., 2007). The short latency of the evoked neck muscle response implicates a largely feedforward mechanism from the frontal cortex, through the

oculomotor brainstem, and from there to spinal cord and motor periphery. The SEF is connected to a number of oculomotor areas within the brainstem, including the intermediate layers of the SC and other oculomotor structures in the pontomedullary reticular formation; either of these could serve as intermediary relays between the Cyclic nucleotide phosphodiesterase SEF and spinal cord [see Chapman et al. (2012) for more

detailed considerations]. It is also possible that the SEF’s influence over neck muscle recruitment is mediated through the FEF, as neck muscle response latencies from this structure are ~5–10 ms shorter than from the SEF (Elsley et al., 2007). Regardless of the precise cortical route, the greater responsiveness of the cephalo- vs. oculomotor circuits is consistent with a series of results in humans and monkeys showing correlates of imposed or adopted subthreshold oculomotor plans in the motor periphery at the neck (Corneil et al., 2004, 2008; Rezvani & Corneil, 2008; Goonetilleke et al., 2010, 2011). We (Corneil, 2011) and others (Galiana & Guitton, 1992; Pélisson et al., 2001; Gandhi & Sparks, 2007) have emphasized the potential role of the omni-pause neurons in the brainstem, which appear to selectively inhibit premotor oculomotor circuits for saccadic gaze shifts without imparting a similar level of influence on cephalomotor commands. Our results also have implications for a potential role of the SEF in eye–head coordination. A central question in motor coordination is how the brain selects a particular pattern of multisegmental coordination from a limitless space of solutions that could all achieve a desired goal (Bernstein, 1967).

While the baseline EMG activity can explain a portion of the resp

While the baseline EMG activity can explain a portion of the response differential on pro- vs. anti-saccade in this timeframe (e.g. the last three stimulation points), our data show that a larger degree of interaction persists on anti-saccade vs. pro-saccade trials (histograms in Figs 5 and 6). How then can we reconcile larger evoked neck muscle responses on anti-saccade trials with the accompanying disruptions of anti-saccade PF-02341066 research buy performance? We begin

by first considering the latency of the neck muscle response evoked by ICMS-SEF. As shown in Fig. 4A, the latency of the evoked neck muscle response is very short, beginning 25–30 ms after stimulation onset and peaking after the stimulation train. We have previously quantified PI3K inhibitor neck muscle response latencies to ICMS-SEF using a variety of methods to be in the range of 30 ms, leading any evoked saccades by ~40–70 ms on average (Chapman et al., 2012). The large difference between the onset latencies of neck muscle responses vs. saccades permits the use of short-duration stimulation as a probe of the excitability of the oculomotor system (Corneil et al., 2007). The short latency of the evoked neck muscle response implicates a largely feedforward mechanism from the frontal cortex, through the

oculomotor brainstem, and from there to spinal cord and motor periphery. The SEF is connected to a number of oculomotor areas within the brainstem, including the intermediate layers of the SC and other oculomotor structures in the pontomedullary reticular formation; either of these could serve as intermediary relays between the Amobarbital SEF and spinal cord [see Chapman et al. (2012) for more

detailed considerations]. It is also possible that the SEF’s influence over neck muscle recruitment is mediated through the FEF, as neck muscle response latencies from this structure are ~5–10 ms shorter than from the SEF (Elsley et al., 2007). Regardless of the precise cortical route, the greater responsiveness of the cephalo- vs. oculomotor circuits is consistent with a series of results in humans and monkeys showing correlates of imposed or adopted subthreshold oculomotor plans in the motor periphery at the neck (Corneil et al., 2004, 2008; Rezvani & Corneil, 2008; Goonetilleke et al., 2010, 2011). We (Corneil, 2011) and others (Galiana & Guitton, 1992; Pélisson et al., 2001; Gandhi & Sparks, 2007) have emphasized the potential role of the omni-pause neurons in the brainstem, which appear to selectively inhibit premotor oculomotor circuits for saccadic gaze shifts without imparting a similar level of influence on cephalomotor commands. Our results also have implications for a potential role of the SEF in eye–head coordination. A central question in motor coordination is how the brain selects a particular pattern of multisegmental coordination from a limitless space of solutions that could all achieve a desired goal (Bernstein, 1967).