bluuebunny/crossref_metadata_2025 huggingface dataset:
Baroreflexes of the rat. VI. Sleep and responses to aortic nerve stimulation in the dmNTS
Authors: Tang Xiaorui , Dworkin Barry R.
Published: January 2010

The sensitivity of the baroreflex determines its stability and effectiveness in controlling blood pressure (BP). Sleep and arousal are reported to affect baroreflex sensitivity, but the findings are not consistent across studies. After statistically correcting the effect of sleep on the baselines in chronically neuromuscular-blocked (NMB) rats, we found that sleep affects BP and heart period (HP) baroreflex gain similarly. This finding is consistent with baroreflex modulation of HP and BP before divergence of the sympathetic and parasympathetic pathways. Therefore, we hypothesized that the gain modulation occurs in the dorsal medial nucleus of the solitary tract (dmNTS). The present study used long-term dmNTS recordings in NMB rats and single-pulse aortic depressor nerve stimulation. Under these conditions, the magnitude of A-fiber evoked responses (ERs), recorded from second- or higher-order dmNTS baroreflex neurons, was reliably augmented during high-amplitude low-frequency EEG activity (slow-wave sleep) and reduced during low-amplitude high-frequency EEG activity (arousal; ΔER = 11%, t = 9.49, P < 0.001, degrees of freedom = 1,016). This result has methodological implications for techniques that use changes in HP to estimate baroreflex BP gain and general implications for understanding the relationship between sleep and cardiovascular control.
Ca2+-driven intestinal HCO3−secretion and CaCO3precipitation in the European flounder in vivo: influences on acid-base regulation and blood gas transport
Authors: Cooper Christopher A. , Whittamore Jonathan M. , Wilson Rod W.
Published: February 2010

Marine teleost fish continuously ingest seawater to prevent dehydration and their intestines absorb fluid by mechanisms linked to three separate driving forces: 1) cotransport of NaCl from the gut fluid; 2) bicarbonate (HCO3−) secretion and Cl−absorption via Cl−/HCO3−exchange fueled by metabolic CO2; and 3) alkaline precipitation of Ca2+as insoluble CaCO3, which aids H2O absorption). The latter two processes involve high rates of epithelial HCO3−secretion stimulated by intestinal Ca2+and can drive a major portion of water absorption. At higher salinities and ambient Ca2+concentrations the osmoregulatory role of intestinal HCO3−secretion is amplified, but this has repercussions for other physiological processes, in particular, respiratory gas transport (as it is fueled by metabolic CO2) and acid-base regulation (as intestinal cells must export H+into the blood to balance apical HCO3−secretion). The flounder intestine was perfused in vivo with salines containing 10, 40, or 90 mM Ca2+. Increasing the luminal Ca2+concentration caused a large elevation in intestinal HCO3−production and excretion. Additionally, blood pH decreased (−0.13 pH units) and plasma partial pressure of CO2(Pco2) levels were elevated (+1.16 mmHg) at the highest Ca perfusate level after 3 days of perfusion. Increasing the perfusate [Ca2+] also produced proportional increases in net acid excretion via the gills. When the net intestinal flux of all ions across the intestine was calculated, there was a greater absorption of anions than cations. This missing cation flux was assumed to be protons, which vary with an almost 1:1 relationship with net acid excretion via the gill. This study illustrates the intimate link between intestinal HCO3−production and osmoregulation with acid-base balance and respiratory gas exchange and the specific controlling role of ingested Ca2+independent of any other ion or overall osmolality in marine teleost fish.
HCO3−secretion and CaCO3precipitation play major roles in intestinal water absorption in marine teleost fish in vivo
Authors: Whittamore Jonathan M. , Cooper Christopher A. , Wilson Rod W.
Published: February 2010

The intestine of marine teleosts must effectively absorb fluid from ingested seawater to avoid dehydration. This fluid transport has been almost exclusively characterized as driven by NaCl absorption. However, an additional feature of the osmoregulatory role of the intestine is substantial net HCO3−secretion. This is suggested to drive additional fluid absorption directly (via Cl−/HCO3−exchange) and indirectly by precipitating ingested Ca2+as CaCO3, thus creating the osmotic gradient for additional fluid absorption. The present study tested this hypothesis by perfusing the intestine of the European flounder in vivo with varying [Ca2+]: 10 (control), 40, and 90 mM. Fractional fluid absorption increased from 47% (control) to 73% (90 mM Ca2+), where almost all secreted HCO3−was excreted as CaCO3. This additional fluid absorption could not be explained by NaCl cotransport. Instead, a significant positive relationship between Na+-independent fluid absorption and total HCO3−secretion was consistent with the predicted roles for anion exchange and CaCO3precipitation. Further analysis suggested that Na+-independent fluid absorption could be accounted for by net Cl−and H+absorption (from Cl−/HCO3−exchange and CO2hydration, respectively). There was no evidence to suggest that CaCO3alone was responsible for driving fluid absorption. However, by preventing the accumulation of luminal Ca2+it played a vital role by dynamically maintaining a favorable osmotic gradient all along the intestine, which permits substantially higher rates of solute-linked fluid absorption. To overcome the resulting hyperosmotic and highly acidic absorbate, it is proposed that plasma HCO3−buffers the absorbed H+(from HCO3−production), and consequently reduces the osmolarity of the absorbed fluid entering the body.
Castration fails to prevent prenatally programmed hypertension in male rats
Authors: Woods Lori L. , Morgan Terry K. , Resko John A.
Published: January 2010

Male offspring of rats that were modestly protein restricted during pregnancy become hypertensive as adults, whereas their female littermates remain normotensive. The purpose of this study was to determine the role of testosterone in promoting this sexual dimorphism of prenatally programmed hypertension. Rats were fed either a normal (19% protein, NP) or modestly protein-restricted (8.5% protein, LP) diet throughout pregnancy. Male offspring either remained intact or were castrated (CAS) at 30 days of age. Female offspring remained intact. At ∼22 wk of age, the offspring were chronically instrumented for measurement of mean arterial pressure and renal function. Intact male LP offspring were hypertensive compared with male NP offspring (138 ± 2 vs. 130 ± 2 mmHg, P < 0.007), whereas female LP offspring were normotensive (123 ± 1 vs. 122 ± 2 mmHg in NP females). In CAS males, blood pressure in both diet groups was not different from that in intact males of the same group (138 ± 3 mmHg in LP CAS males, and 131 ± 2 mmHg in NP CAS males). Glomerular filtration rate and effective renal plasma flow were also not significantly affected by castration. However, castration significantly reduced protein excretion in LP males to levels not different from those in NP CAS and intact males. Renal histopathology scores showed a similar pattern. Thus removal of androgens by castration failed to provide any protective effect against the hypertension programmed by maternal protein restriction. Castration also failed to abolish the sex difference in blood pressure in both diet groups. These findings suggest that the lifelong presence of normal levels of testicular hormones does not play a major role either in maintaining baseline blood pressure higher in males than in females, or in promoting further elevations in blood pressure in males due to prenatal undernutrition. However, androgens such as testosterone may promote renal injury in LP males.
Cyclooxygenase 2 inhibition exacerbates AQP2 and pAQP2 downregulation independently of V2 receptor abundance in the postobstructed kidney
Authors: Jensen Anja M. , Bae Eun Hui , Nørregaard Rikke , Wang Guixian , Nielsen Søren , Schweer Horst , Kim Soo Wan , Frøkiær Jørgen
Published: January 2010

Previously we demonstrated that ANG II receptor (AT1R) blockade attenuates V2 receptor (V2R), AQP2, and pS256-AQP2 downregulation in the postobstructed kidney and partially reverses obstruction-induced inhibition of cAMP generation and cyclooxygenase 2 (COX-2) induction. Therefore, we speculated whether the effects of AT1R blockade on V2R and the vasopressin-regulated pathway are attributable to attenuated COX-2 induction. To examine this, rats were subjected to 24-h bilateral ureteral obstruction (BUO) followed by 48-h release and treated with the COX-2 inhibitor parecoxib or saline. Control rats were sham-operated. Parecoxib treatment significantly reduced urine output 24 h after release of BUO whereas urine osmolality and solute-free water reabsorption was comparable between saline- and parecoxib-treated BUO rats. Immunoblotting revealed a significant decrease in AQP2 and pS256-AQP2 abundance to 20 and 23% of sham levels in parecoxib-treated BUO rats compared with 40 and 55% of sham levels in saline-treated BUO rats. Immunohistochemistry confirmed the exacerbated AQP2 and pS256-AQP2 downregulation in parecoxib-treated BUO rats. Finally, parecoxib treatment had no effect on V2R downregulation and the inhibited, vasopressin-stimulated cAMP generation in inner medullary membrane fractions from the postobstructed kidney. In conclusion, COX-2 inhibition exacerbates AQP2 and pS256-AQP2 downregulation 48 h after release of 24-h BUO independently of V2R abundance and vasopressin-stimulated cAMP generation. The results indicate that COX-2 inhibition does not mimic AT1R blockade-mediated effects and that AT1R-mediated AQP2 regulation in the postobstructed kidney collecting duct is independent of COX-2 induction.
Influence of endurance training on central sympathetic outflow to skeletal muscle in response to a mixed meal
Authors: Young Colin N. , Deo Shekhar H. , Kim Areum , Horiuchi Masahiro , Mikus Catherine R. , Uptergrove Grace M. , Thyfault John P. , Fadel Paul J.
Published: January 2010

Nutrient intake is accompanied by increases in central sympathetic outflow, a response that has been mainly attributed to insulin. Insulin-mediated sympathoexcitation appears to be blunted in insulin-resistant conditions, suggesting that aside from peripheral insulin insensitivity, such conditions may also impair the central action of insulin in mediating sympathetic activation. What remains unclear is whether an insulin-sensitive state, such as that induced by chronic endurance training, alters the central sympathetic effects of insulin during postprandial conditions. To examine this question plasma insulin and glucose, muscle sympathetic nerve activity (MSNA), heart rate, and arterial blood pressure were measured in 11 high-fit [HF; peak oxygen uptake (V̇o2peak) 65.9 ± 1.4 ml·kg−1·min−1] and 9 average-fit (AF; V̇o2peak 43.6 ± 1.3 ml·kg−1·min−1) male subjects before and for 120 min after ingestion of a mixed meal drink. As expected, the insulin response to meal ingestion was lower in HF than AF participants (insulin area under the curve0–120: 2,314 ± 171 vs. 4,028 ± 460 μIU·ml−1·120−1, HF vs. AF, P < 0.05), with similar plasma glucose responses between groups. Importantly, following consumption of the meal, the HF subjects demonstrated a greater rise in MSNA compared with the AF subjects (e.g., 120 min: Δ21 ± 1 vs. 8 ± 3 bursts/100 heart beats, HF vs. AF, P < 0.05). Furthermore, when expressed relative to plasma insulin, HF subjects exhibited a greater change in MSNA for any given change in insulin. Arterial blood pressure responses following meal intake were similar between groups. Collectively, these data suggest that, in addition to improved peripheral insulin sensitivity, endurance training may enhance the central sympathetic effect of insulin to increase MSNA following consumption of a mixed meal.
Operant Conditioning of Primate Prefrontal Neurons
Authors: Kobayashi Shunsuke , Schultz Wolfram , Sakagami Masamichi
Published: January 2010

An operant is a behavioral act that has an impact on the environment to produce an outcome, constituting an important component of voluntary behavior. Because the environment can be volatile, the same action may cause different consequences. Thus to obtain an optimal outcome, it is crucial to detect action–outcome relationships and adapt the behavior accordingly. Although prefrontal neurons are known to change activity depending on expected reward, it remains unknown whether prefrontal activity contributes to obtaining reward. We investigated this issue by setting variable relationships between levels of single-neuron activity and rewarding outcomes. Lateral prefrontal neurons changed their spiking activity according to the specific requirements for gaining reward, without the animals making a motor response. Thus spiking activity constituted an operant response. Data from a control task suggested that these changes were unlikely to reflect simple reward predictions. These data demonstrate a remarkable capacity of prefrontal neurons to adapt to specific operant requirements at the single-neuron level.
Shared Cortical Systems for Processing of Horizontal and Vertical Sound Motion
Authors: Getzmann Stephan , Lewald Jörg
Published: January 2010

Cortical processing of horizontal and vertical sound motion in free-field space was investigated using high-density electroencephalography in combination with standardized low-resolution brain electromagnetic tomography (sLORETA). Eighteen subjects heard sound stimuli that, after an initial stationary phase in a central position, started to move centrifugally, either to the left, to the right, upward, or downward. The delayed onset of both horizontal and vertical motion elicited a specific motion-onset response (MOR), resulting in widely distributed activations, with prominent maxima in primary and nonprimary auditory cortices, insula, and parietal lobe. The comparison of MORs to horizontal and vertical motion orientations did not indicate any significant differences in latency or topography. Contrasting the sLORETA solutions for the two motion orientations revealed only marginal activation in postcentral gyrus. These data are consistent with the notion that azimuth and elevation components of dynamic auditory spatial information are processed in common, rather than separate, cortical substrates. Furthermore, the findings support the assumption that the MOR originates at a stage of auditory analysis after the different spatial cues (interaural and monaural spectral cues) have been integrated into a unified space code.
Conjunction of Vocal Production and Perception Regulates Expression of the Immediate Early Gene ZENK in a Novel Cortical Region of Songbirds
Authors: Bottjer Sarah W. , Alderete Tanya L. , Chang Daniel
Published: January 2010

The cortical nucleus LMAN (lateral magnocellular nucleus of the anterior nidopallium) provides the output of a basal ganglia pathway that is necessary for acquisition of learned vocal behavior during development in songbirds. LMAN is composed of two subregions, a core and a surrounding shell, that give rise to independent pathways that traverse the forebrain in parallel. The LMANshell pathway forms a recurrent loop that includes a cortical region, the dorsal region of the caudolateral nidopallium (dNCL), hitherto unknown to be involved with learned vocal behavior. Here we show that vocal production strongly induces the IEG product ZENK in dNCL of zebra finches. Hearing tutor song while singing is more effective at inducing expression in dNCL of juvenile birds during the auditory–motor integration stage of vocal learning than is hearing conspecific song. In contrast, hearing conspecific song is relatively more effective at inducing expression in adult birds, regardless of whether they are producing song. Furthermore, ZENK+ neurons in dNCL include projection neurons that are part of the LMANshell recurrent loop and a high proportion of dNCL projection neurons express ZENK in singing juvenile birds that hear tutor song. Thus juvenile birds that are actively refining their vocal pattern to imitate a tutor song show high levels of ZENK induction in dNCL neurons when they are singing while hearing the song of their tutor and low levels when they hear a novel conspecific. This pattern indicates that dNCL is a novel brain region involved with vocal learning and that its function is developmentally regulated.
The Cricket Cercal System Implements Delay-Line Processing
Authors: Mulder-Rosi Jonas , Cummins Graham I. , Miller John P.
Published: January 2010

The cercal sensory system of crickets mediates sensitivity to low-amplitude air currents. The sense organ for this system is a pair of antenna-like abdominal appendages called cerci, each of which is about 1 cm long in normal adult crickets. Although this system has been used extensively as a model system for studying the mechanisms underlying neural coding at the cellular and system levels, no previous studies have considered the functional significance of the physical dimensions of cerci. We show that the differential conduction characteristics of the receptor array in Acheta domesticus crickets are of substantial significance. All filiform sensory afferent axons we examined had the same propagation speeds to within a small variance, resulting in a significant and systematic differential propagation time for spikes from sensory receptors at different locations along the structure. Thus the sensory structures operate as delay lines. The delay-line structure supports neural computations in many of the projecting cercal interneurons (INs) that yield substantial differential sensitivity to the direction and velocity of naturalistic stimuli. Several INs show delay-line-derived sensitivities that are equivalent, in an engineering sense, to “notch filtering,” through which background noise is selectively eliminated by the delay-line-based processing.
Song Recognition Learning and Stimulus-Specific Weakening of Neural Responses in the Avian Auditory Forebrain
Authors: Thompson Jason V. , Gentner Timothy Q.
Published: January 2010

Learning typically increases the strength of responses and the number of neurons that respond to training stimuli. Few studies have explored representational plasticity using natural stimuli, however, leaving unknown the changes that accompany learning under more realistic conditions. Here, we examine experience-dependent plasticity in European starlings, a songbird with rich acoustic communication signals tied to robust, natural recognition behaviors. We trained starlings to recognize conspecific songs and recorded the extracellular spiking activity of single neurons in the caudomedial nidopallium (NCM), a secondary auditory forebrain region analogous to mammalian auditory cortex. Training induced a stimulus-specific weakening of the neural responses (lower spike rates) to the learned songs, whereas the population continued to respond robustly to unfamiliar songs. Additional experiments rule out stimulus-specific adaptation and general biases for novel stimuli as explanations of these effects. Instead, the results indicate that associative learning leads to single neuron responses in which both irrelevant and unfamiliar stimuli elicit more robust responses than behaviorally relevant natural stimuli. Detailed analyses of these effects at a finer temporal scale point to changes in the number of motifs eliciting excitatory responses above a neuron's spontaneous discharge rate. These results show a novel form of experience-dependent plasticity in the auditory forebrain that is tied to associative learning and in which the overall strength of responses is inversely related to learned behavioral significance.
Shaping the Optimal Repetition Interval for Cathodal Transcranial Direct Current Stimulation (tDCS)
Authors: Monte-Silva Katia , Kuo Min-Fang , Liebetanz David , Paulus Walter , Nitsche Michael A.
Published: January 2010

Transcranial DC stimulation (tDCS) is a plasticity-inducing noninvasive brain stimulation tool with various potential therapeutic applications in neurological and psychiatric diseases. Currently, the duration of the aftereffects of stimulation is restricted. For future clinical applications, stimulation protocols are required that produce aftereffects lasting for days or weeks. Options to prolong the effects of tDCS are further prolongation or repetition of tDCS. Nothing is known thus far about optimal protocols in this behalf, although repetitive stimulation is already performed in clinical applications. Thus we explored the effects of different break durations on cathodal tDCS-induced cortical excitability alterations. In 12 subjects, two identical periods of cathodal tDCS (9-min duration; 1 mA) with an interstimulation interval of 0 (no break), 3, or 20 min or 3 or 24 h were performed. The results indicate that doubling stimulation duration without a break prolongs the aftereffects from 60 to 90 min after tDCS. When the second stimulation was performed during the aftereffects of the first, a prolongation and enhancement of tDCS-induced effects for ≤120 min after stimulation was observed. In contrast, when the second stimulation followed the first one after 3 or 24 h, the aftereffects were initially attenuated, or abolished, but afterwards re-established for up to 120 min after tDCS in the 24-h condition. These results suggest that, for prolonging the aftereffects of cathodal tDCS, stimulation interval might be important.
Sensations Evoked by Microstimulation of Single Mechanoreceptive Afferents Innervating the Human Face and Mouth
Authors: Trulsson M. , Essick G. K.
Published: February 2010

Intraneural microneurography and microstimulation were performed on single afferent axons in the inferior alveolar and lingual nerves innervating the face, teeth, labial, or oral mucosa. Using natural mechanical stimuli, 35 single mechanoreceptive afferents were characterized with respect to unit type [fast adapting type I (FA I), FA hair, slowly adapting type I and II (SA I and SA II), periodontal, and deep tongue units] as well as size and shape of the receptive field. All afferents were subsequently microstimulated with pulse trains at 30 Hz lasting 1.0 s. Afferents recordings whose were stable thereafter were also tested with single pulses and pulse trains at 5 and 60 Hz. The results revealed that electrical stimulation of single FA I, FA hair, and SA I afferents from the orofacial region can evoke a percept that is spatially matched to the afferent's receptive field and consistent with the afferent's response properties as observed on natural mechanical stimulation. Stimulation of FA afferents typically evoked sensations that were vibratory in nature; whereas those of SA I afferents were felt as constant pressure. These afferents terminate superficially in the orofacial tissues and seem to have a particularly powerful access to perceptual levels. In contrast, microstimulation of single periodontal, SA II, and deep tongue afferents failed to evoke a sensation that matched the receptive field of the afferent. These afferents terminate more deeply in the tissues, are often active in the absence of external stimulation, and probably access perceptual levels only when multiple afferents are stimulated. It is suggested that the spontaneously active afferents that monitor tension in collagen fibers (SA II and periodontal afferents) may have the role to register the mechanical state of the soft tissues, which has been hypothesized to help maintain the body's representation in the central somatosensory system.
The Effect of Noise on CaMKII Activation in a Dendritic Spine During LTP Induction
Authors: Zeng Shangyou , Holmes William R.
Published: January 2010

Activation of calcium-calmodulin dependent protein kinase II (CaMKII) during induction of long-term potentiation (LTP) is a series of complicated stochastic processes that are affected by noise. There are two main sources of noise affecting CaMKII activation within a dendritic spine. One is the noise associated with stochastic opening of N-methyl-d-aspartate (NMDA) receptor channels and the other is the noise associated with the stochastic reaction-diffusion kinetics leading to CaMKII activation. Many models have been developed to simulate CaMKII activation, but there is no fully stochastic model that studies the effect of noise on CaMKII activation. Here we construct a fully stochastic model to study these effects. Our results show that noise has important effects on CaMKII activation variability, with the effect from stochastic opening of NMDA receptor channels being 5–10 times more significant than that from stochastic reactions involving CaMKII. In addition, CaMKII activation levels and the variability of activation are greatly affected by small changes in NMDA receptor channel number at the synapse. One reason LTP induction protocols may require tetanic or repeated burst stimulation is that there is a need to overcome inherent variability to provide sufficiently large calcium signals through NMDA receptor channels; with meaningful physiological stimuli, noise may allow the calcium signal to exceed threshold for CaMKII activation when it might not do so otherwise.
A Multisampling Reporter System for Monitoring MicroRNA Activity in the Same Population of Cells
Authors: Huang Pei-Chen , Chen Chih-Ying , Yang Feng-Yuan , Au Lo-Chun
Published: February 2010

MicroRNAs (miRNAs) downregulate gene expression by binding to the partially complementary sites in the 3′ untranslated region (UTR) of target mRNAs. Several methods, such as Northern blot analysis, quantitative real‐time RT‐PCR, microarray, and the luciferase reporter system, are commonly used to quantify the relative level or activity of miRNAs. The disadvantage of these methods is the requirement for cell lysis, which means that several sets of wells/dishes of cells must be prepared to monitor changes in miRNA activity in time‐course studies. In this study, we developed a multisampling reporter system in which two secretable bioluminescence‐generating enzymes are employed, one as a reporter and the other as an internal control. The reporters consist of a pair of vectors containing the Metridia luciferase gene, one with and one without a duplicated miRNA targeting sequence at their 3′UTR, while the other vector coding for the secreted alkaline phosphatase gene is used as an internal control. This method allows miRNA activity to be monitored within the same population of cells over time by withdrawing aliquots of the culture medium. The practicability and benefits of this system are addressed in this report.
Studies of the Suitability of Fowlpox as a Decontamination and Thermal Stability Simulant for Variola Major
Authors: Chambers Amanda E. , Dixon Melissa M. , Harvey Steven P.
Published: January 2010

Variola major, the causative agent of smallpox, has been eradicated from nature. However, stocks still exist; thus, there is a need for relevant decontamination studies, preferably with nonpathogenic simulants. Previous studies have shown a similarity in response of vaccinia virus and variola major to various decontaminants and thermal inactivation. This study compared vaccinia and fowlpox viruses under similar conditions, using disinfectants and temperatures for which variola major data already existed. Most disinfectants showed similar efficacy against vaccinia and fowlpox, suggesting the utility of fowlpox as a decontamination simulant. Inactivation kinetics studies showed that fowlpox behaved similarly to variola major when treated with 0.1% iodine and 5.7% polyethyleneglycol nonylphenyl ether, 0.025% sodium hypochlorite, 0.05% sodium hypochlorite, and 0.1% cetyltrimethylammonium chloride and 0.05% benzalkonium chloride, but differed in its response to 0.05% iodine and 0.3% polyethyleneglycol nonylphenyl ether and 40% ethanol. Thermal inactivation studies demonstrated that fowlpox is a suitable thermal simulant for variola major between and .
Aberrant Expression of Critical Genes during Secondary Cell Wall Biogenesis in a Cotton Mutant, Ligon Lintless-1 (Li-1)
Authors: Bolton James J. , Soliman Khairy M. , Wilkins Thea A. , Jenkins Johnie N.
Published: January 2010

Over ninety percent of the value of cotton comes from its fiber; however, the genetic mechanisms governing fiber development are poorly understood. Due to their biochemical and morphological diversity in fiber cells cotton fiber mutants have been useful in examining fiber development; therefore, using the Ligon Lintless (Li-1) mutant, a monogenic dominant cotton mutant with very short fibers, we employed the high throughput approaches of microarray technology and real time PCR to gain insights into what genes were critical during the secondary cell wall synthesis stage. Comparative transcriptome analysis of the normal TM-1 genotype and the near isogenicLi-1 revealed that over 100 transcripts were differentially expressed at least 2-fold during secondary wall biogenesis, although the genetic profile of the expansion phase showed no significant differences in the isolines. Of particular note, we identified three candidate gene families-expansin, sucrose synthase, and tubulin—whose expression inLi-1 deviates from normal expression patterns of its parent, TM-1. These genes may contribute to retarded growth of fibers inLi-1 since they are fiber-expressed structural and metabolic genes. This work provides more details into the mechanisms of fiber development, and suggests theLigene is active during the later stages of fiber development.
Classification of All Associative Mono‐n‐ary Algebras with 2 Elements
Authors: Andres Stephan Dominique
Published: January 2010

We consider algebras with a single n‐ary operation and a certain type of associativity. We prove that (up to isomorphism) there are exactly 5
of these associative mono‐n‐ary algebras with 2 elements for even n ≥ 2 and 6 for odd n ≥ 3. These algebras are described explicitly. It is shown that a similar result is impossible for algebras with at least 4 elements. An application concerning the assignment of a control bit to a string is given.
Comparative Clinical Study of Two Tooth Bleaching Protocols with 6% Hydrogen Peroxide
Authors: Oteo Calatayud Jesús , Mateos de la Varga Paloma , Oteo Calatayud Carlos , Calvo Box María José
Published: February 2010

Objective.The objective was to compare the clinical efficacy of two different tooth bleaching protocols after 1 and 2 weeks of treatment with an over-the-counter paint-on gel containing 6% hydrogen peroxide.Material and methods.Sixteen volunteer patients (minimum shade A2 or darker on maxillary teeth) were selected to participate in this randomized, single-blind (examiner-blinded), single-center, 2-group clinical trial using a divided mouth model. The product was applied in our clinic to one hemi-arch (Group I) in each patient at two sessions one week apart, making five applications at each session (separated by 10 min intervals). The patients themselves applied the product once a day for 10 days in the other hemiarch (Group II). Efficacy was measured according to the Vita Classical shade guide at baseline and at one and two weeks. Differences between groups (office-treated vs. home-treated hemiarches) were tested by repeated-measures analysis of variance.Results.Significant () differences in shade values were detected between pre- and post-bleaching in both groups. The two groups did not significantly differ in tooth shade at the end of the treatment.Conclusions.Treatment with 6% hydrogen peroxide gel using the paint-on system shows significant clinical efficacy whether applied by clinicians or by the patients themselves.
Existence and Exponential Stability of Periodic Solution for a Class of Generalized Neural Networks with Arbitrary Delays
Authors: Zhang Yimin , Li Yongkun , Ye Kuohui
Published: January 2010

By the continuation theorem of coincidence degree and M‐matrix theory, we obtain some sufficient conditions for the existence and exponential stability of periodic solutions for a class of generalized neural networks with arbitrary delays, which are milder and less restrictive than those of previous known criteria. Moreover our results generalize and improve many existing ones.
Recurrence Quantification Analysis of Spontaneous Electrophysiological Activity during Development: Characterization of In Vitro Neuronal Networks Cultured on Multi Electrode Array Chips
Authors: Novellino Antonio , Zaldívar José-Manuel
Published: January 2010

The combination of a nonlinear time series analysis technique, Recurrence Quantification Analysis (RQA) based on Recurrence Plots (RPs), and traditional statistical analysis for neuronal electrophysiology is proposed in this paper as an innovative paradigm for studying the variation of spontaneous electrophysiological activity of in vitro Neuronal Networks (NNs) coupled to Multielectrode Array (MEA) chips. Recurrence, determinism, entropy, distance of activity patterns, and correlation in correspondence to spike and burst parameters (e.g., mean spiking rate, mean bursting rate, burst duration, spike in burst, etc.) have been computed to characterize and assess the daily changes of the neuronal electrophysiology during neuronal network development and maturation. The results show the similarities/differences between several channels and time periods as well as the evolution of the spontaneous activity in the MEA chip. RPs could be used for graphically exploring possible neuronal dynamic breaking/changing points, whereas RQA parameters are suited for locating them. The combination of RQA with traditional approaches improves the identification, description, and prediction of electrophysiological changes and it will be used to allow intercomparison between results obtained from different MEA chips. Results suggest the proposed processing paradigm as a valuable tool to analyze neuronal activity for screening purposes (e.g., toxicology, neurodevelopmental toxicology).
Vitamin D Deficiency in Cystic Fibrosis
Authors: Hall William B. , Sparks Amy A. , Aris Robert M.
Published: January 2010

Cystic Fibrosis is the most common inherited genetic respiratory disorder in the Western World. Hypovitaminosis D is almost universal in CF patients, likely due to a combination of inadequate absorption, impaired metabolism, and lack of sun exposure. Inadequate levels are associated with the high prevalence of bone disease or osteoporosis in CF patients, which is associated with increased morbidity including fractures, kyphosis, and worsening pulmonary status. Treatment goals include regular monitoring 25 hydroxyvitamin D (25OHD) levels with aggressive treatment for those with levels <75 nmol/L (<30 ng/mL). More research is needed to determine optimal supplementation goals and strategies.
Astrobiology with Robotic Telescopes at CAB
Authors: Cuesta Luis , Eibe M. Teresa , Ullán Aurora , Pérez-Verde Antonio , Navas Jorge
Published: January 2010

The key objectives of RTRCAB are the identification of new exoplanets and especially the characterization of the known exoplanets by observing photometric and systematic monitoring of their transits. These telescopes, equipped with advanced technology, optimized control programs, and optical and technical characteristics adequate for this purpose, are ideal to make the observations that are required to carry out these programs. The achievement of these goals is ensured by the existence of three separated geographical stations. In this sense, there are several planned missions that have the same objectives among their scientific goals, like Kepler, CoRoT, GAIA, and PLATO.
Fixed Point Theorems on Spaces Endowed with Vector-Valued Metrics
Authors: Filip Alexandru-Darius , Petruşel Adrian
Published: January 2010

The purpose of this work is to present some (local and global) fixed point results for singlevalued and multivalued generalized contractions on spaces endowed with vector-valued metrics. The results are extensions of some theorems given by Perov (1964), Bucur et al. (2009), M. Berinde and V. Berinde (2007), O'Regan et al. (2007), and so forth.
Estimation of Mass Ratio of the Total Kernels within a Sample of In‐Shell Peanuts Using RF Impedance Method
Authors: Kandala Chari V. , Sundaram Jaya
Published: January 2010

It would be useful to know the total kernel mass within a given mass of peanuts (mass ratio) while the peanuts are bought or being processed. In this work, the possibility of finding the mass ratio while the peanuts were in their shells was investigated. Capacitance, phase angle, and dissipation factor measurements on a parallel‐plate capacitor holding in‐shell peanut samples were made at frequencies from 1 to 10 MHz insteps of 1 MHz. A calibration equation was developed by multilinear regression analysis correlating the percentage ratio of the kernel weight with the measured capacitance, dissipation factor, and phase angle values of in‐shell peanut samples with known kernel weights. The equation was used to predict the percentage mass ratio in the validation groups. Fitness of calibration model was verified using standard error of calibration, root mean square error of calibration, and leverage and influence plots. The predictability percentage, within 1% and 2% of the visual determination, was calculated by comparing the kernel mass ratio, obtained by the model equation and the reference value obtained by visual determination. Cross‐validation gave 96% and 100% predictability, and external validation gave 87% and 98% predictability within 1% and 2% difference, respectively.
Laparoscopic Cholecystectomy Combined Using Miniaturised Instruments in Transgastric Gall Bladder Removal: Performed on 63 Patients
Authors: Jurczak Florent , Pousset Jean-Paul
Published: January 2010

Background. The laparoscopic cholecystectomy is a perfectly codified surgical procedure. The development of recent innovative and experimental surgical techniques Natural Orifice transluminal endoscopic surger (N.O.T.E.S.) which reduces the abdominal wall trauma leads us to develop a combined procedure of a standard dissection using miniaturised instruments already existing on the market (3 and 5 mm wide) and a gall bladder removal through a short gastrotomy Natural Orifice Specimen Extraction (N.O.S.E.).Methods. Our objective was to evaluate the safety, the feasibility, and the reproducibility of our new approach. After reviewing existing products on the market and a feasibility study, we put in place a protocol in our structure for patients on whom the procedure was performed. We carried out a gall bladder removal by a short gastrotomy, located on the anterior gastric wall, which then reduced the abdominal wall trauma and allowed them to resume normal physical activity quickly without risk of trocar site hernia.Results. We performed the procedure described in this paper on 63 patients, between April 2008 and July 2009. There were 14 men and 49 women with an average age of 46.8 years (ranging from 28 to 77) and an average BMI of 27.2. 30 patients had at least one gallstone larger than 10 mm. There was no postoperative gastric or abdominal wall complication and a fast recovery for all the patients in our study.Conclusions. This procedure is feasible, reproducible, with good results and minimal abdominal wall trauma. It is also safer than N.O.T.E.S. and endoscopic clipping and recovery, allowing normal physical activity, fast and, without risk of incisional hernia.
Substance P Signaling Contributes to Granuloma Formation inTaenia crassicepsInfection, a Murine Model of Cysticercosis
Authors: Garza Armandina , Tweardy David J. , Weinstock Joel , Viswanathan Balaji , Robinson Prema
Published: January 2010

Cysticercosis is an infection with larval cysts of the cestodeTaenia solium. Through pathways that are incompletely understood, dying parasites initiate a granulomatous reaction that, in the brain, causes seizures. Substance P (SP), a neuropeptide involved in pain-transmission, contributes to inflammation and previously was detected in granulomas associated with deadT. crassicepscysts. To determine if SP contributes to granuloma formation, we measured granuloma-size and levels of IL-1β, TNF-α, and IL-6 within granulomas inT. crassiceps-infected wild type (WT) mice and mice deficient in SP-precursor (SPP) or the SP-receptor (neurokinin 1, NK1). Granuloma volumes of infected SPP- and NK1-knockout mice were reduced by 31 and 36%, respectively, compared to WT mice (P<.05for both) and produced up to 5-fold less IL-1β, TNF-α, and IL-6 protein. Thus, SP signaling contributes to granuloma development and proinflammatory cytokine production inT. crassicepsinfection and suggests a potential role for this mediator in human cystercercosis.
Progesterone and the Spinal Cord: Good Friends in Bad Times
Authors: Labombarda Florencia , González Deniselle María Claudia , De Nicola Alejandro Federico , González Susana Laura
Published: February 2010

In recent years, a growing list of publications point to the value of steroid hormones as an interesting option for the treatment of several type of lesions and diseases of the nervous system. Progesterone, well known for its role in pregnancy, has recently been shown to exert neuroprotective and promyelinating effects in both, the peripheral and central nervous system, including the injured spinal cord. Previous work from our laboratory has shown that progesterone actions in experimental models of spinal neurodegeneration or injury may involve the modulation of brain-derived neurotrophic factor, a neurotrophin with important implications in neuronal survival and axonal regeneration. The spinal cord is target for progesterone since neurons and glial cells express the intracellular receptors for this neuroactive steroid. However, the presence in the spinal cord of new membrane receptors and the enzymes involved in progesterone metabolism to its reduced derivatives, which modulate the activity of neurotransmitter receptors, suggest that progesterone actions involve pleiotropic mechanisms. Our recent data uncovering several molecular events may help to understand the protective and promyelinating actions of progesterone and further support the role of this steroid as a promising therapeutic agent for neurotrauma and/or neurodegenerative diseases.
Effects of Stress on the Immune Response to Theiler’s Virus – Implications for Virus-Induced Autoimmunity
Authors: Welsh C. Jane , Steelman Andrew J. , Mi Wentao , Young Colin R. , Dean Dana D. , Storts Ralph , Welsh, Jr. Thomas H. , Meagher Mary W.
Published: February 2010

Psychological stress is an important factor in susceptibility to many diseases. Our laboratory has been investigating the impact of stress on the susceptibility to Theiler’s virus-induced demyelination (TVID), a mouse model of multiple sclerosis. Using immunodominant viral peptides specific for identification of either CD4+ or CD8+ T cells, stress reduced IFN-γ-producing virus-specific CD4+ and CD8+ T cells in the spleen and CD8+ T cells in the CNS. Expression of mRNA for the Th1 transcription factor T-bet and the Th2 transcription factor GATA-3 were decreased in spleen cells isolated from stressed mice. Cytokine production by cells isolated from the CNS or spleens following stimulation with virus indicated that stress decreased both type 1 and type 2 responses. The adverse effects of stress were partially reversed by concurrent RU486 administration but mimicked by dexamethasone, indicating a major role for glucocorticoids. Global stress-induced immunosuppression resulted in higher levels of virus replication and dissemination. The higher viral load subsequently led to an earlier disease onset and more severe clinical and histological signs of demyelinating disease. Our results have important implications for understanding the pathogenesis of MS, and suggest that stressful events during early infection with an agent capable of inducing demyelination may result in immunosuppression and failure to eliminate the pathogen, which in turn may lead to the development of MS.
Neuroimmunomodulation in the Pathogenesis of Alzheimer’s Disease
Authors: Morales Inelia , Farías Gonzalo , Maccioni Ricardo B.
Published: February 2010

Evidence has been cumulated on the role of microglia cells deregulation and alterations in their interaction patterns with brain neurons, in the pathway towards neurodegeneration in Alzheimer’s disease (AD). After the failure of the amyloid hypothesis to explain AD pathogenesis, current hypotheses focus on tau self-polymerization into pathological oligomers and filaments as a major culprit for neurofibrillary degeneration. It is worth pointing out that formation of tau polymers is consistent with the clinical and neuropathological observations, and that tangles are pathognomonic of AD and related tau disorders. In this context, inflammatory processes play a major role in neuronal degeneration. On the basis of studies on microglia and neuronal cultures, together with experiments in animal models, and the clinical evidence, we postulated that a series of endogenous damage signals activate microglia cells, inducing NFĸ-β with the consequent release of cytokine mediators such as TNF-α, IL-6 and IL-1β. An overexpression of these mediators may trigger signaling cascades in neurons leading to activation of protein kinases gsk3β, cdk5, abl kinases, along with inactivation of phosphatases such as PP1, with the resulting hyperphosphorylation and self-aggregation of tau protein into neurotoxic oligomeric species.
Higher Fish Consumption in Pregnancy May Confer Protection against the Harmful Effect of Prenatal Exposure to Fine Particulate Matter
Authors: Jedrychowski Wieslaw , Perera Frederica , Mrozek-Budzyn Dorota , Flak Elzbieta , Mroz Elzbieta , Sochacka-Tatara Elzbieta , Jacek Ryszard , Kaim Irena , Skolicki Zbigniew , Spengler John D.
Published: February 2010

Background/Aim: The objective of this study was to assess a hypothesized beneficial effect of fish consumption during the last trimester of pregnancy on adverse birth outcomes resulting from prenatal exposure to fine air particulate matter. Methods: The cohort consisted of 481 nonsmoking women with singleton pregnancies, of 18–35 years of age, who gave birth at term. All recruited women were asked about their usual diet over the period of pregnancy. Measurements of particulate matter less than 2.5 µm in size (PM2.5) were carried out by personal air monitoring over 48 h during the second trimester of pregnancy. The effect of PM2.5 and fish intake during gestation on the birth weight of the babies was estimated from multivariable linear regression models, which beside the main independent variables considered a set of potential confounding factors such as the size of the mother (height, prepregnancy weight), maternal education, parity, the gender of the child, gestational age and the season of birth. Results: The study showed that the adjusted birth weight was significantly lower in newborns whose mothers were exposed to particulate matter greater than 46.3 µg/m3 (β coefficient = –97.02, p = 0.032). Regression analysis stratified by the level of maternal fish consumption (in tertiles) showed that the deficit in birth weight amounted to 133.26 g (p = 0.052) in newborns whose mothers reported low fish intake (<91 g/week). The birth weight deficit in newborns whose mothers reported medium (91–205 g/week) or higher fish intake (>205 g/week) was insignificant. The interaction term between PM2.5 and fish intake levels was also insignificant (β = –107,35, p = 0.215). Neither gestational age nor birth weight correlated with maternal fish consumption. Conclusions: The results suggest that a higher consumption of fish by women during pregnancy may reduce the risk of adverse effects of prenatal exposure to toxicants and highlight the fact that a full assessment of adverse birth outcomes resulting from prenatal exposure to ambient hazards should consider maternal nutrition during pregnancy.