Discriminating species of Sinipta Stål (Orthoptera: Acrididae) from Uruguay based on morphological,ethological and molecular data

Two species of the genus Sinipta, S. dalmani and S. hectorisperonii, exist in Uruguay, the latter reported here for the first time. Both species have quite similar morphological features and can only be distinguished by slight details, which have led to misidentifications in the past. Specimens from both taxa were studied in order to detect suitable characters to distinguish them and to clarify their taxonomic status, by integrating previously unstudied morphological, biological and molecular characteristics. Detailed structures of the stridulatory file of both sexes were studied and described for the first time, and the sounds produced by both species were studied and described on the basis of recordings made in captivity with an analog recorder. The signal was digitized and analyzed using Avisoft software. Three different types of sound were described for both species: calling song, courtship song and disturbance song. Oscillograms and frequency spectra were provided, and the physical characteristics of the sounds of interest for species identification were established. Finally, molecular studies showed that the two taxa are reciprocally monophyletic groups. The combined results of the analyses suggest that the two studied taxa are distinct species, and point to features suitable for their identification.     

RNA Expression Profiling of Human iPSC-Derived Cardiomyocytes in a Cardiac Hypertrophy Model

Cardiac hypertrophy is an independent risk factor for cardiovascular disease and heart failure. There is increasing evidence that microRNAs (miRNAs) play an important role in the regulation of messenger RNA (mRNA) and the pathogenesis of various cardiovascular diseases. However, the ability to comprehensively study cardiac hypertrophy on a gene regulatory level is impacted by the limited availability of human cardiomyocytes. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) offer the opportunity for disease modeling. Here we utilize a previously established in vitro model of cardiac hypertrophy to interrogate the regulatory mechanism associated with the cardiac disease process. We perform miRNA sequencing and mRNA expression analysis on endothelin 1 (ET-1) stimulated hiPSC-CMs to describe associated RNA expression profiles. MicroRNA sequencing revealed over 250 known and 34 predicted novel miRNAs to be differentially expressed between ET-1 stimulated and unstimulated control hiPSC-CMs. Messenger RNA expression analysis identified 731 probe sets with significant differential expression. Computational target prediction on significant differentially expressed miRNAs and mRNAs identified nearly 2000 target pairs. A principal component analysis approach comparing the in vitro data with human myocardial biopsies detected overlapping expression changes between the in vitro samples and myocardial biopsies with Left Ventricular Hypertrophy. These results provide further insights into the complex RNA regulatory mechanism associated with cardiac hypertrophy.     

Opiate-Induced Suppression of Rat Hypoglossal Motoneuron Activity and Its Reversal by Ampakine Therapy

Background

Hypoglossal (XII) motoneurons innervate tongue muscles and are vital for maintaining upper-airway patency during inspiration. Depression of XII nerve activity by opioid analgesics is a significant clinical problem, but underlying mechanisms are poorly understood. Currently there are no suitable pharmacological approaches to counter opiate-induced suppression of XII nerve activity while maintaining analgesia. Ampakines accentuate α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor responses. The AMPA family of glutamate receptors mediate excitatory transmission to XII motoneurons. Therefore the objectives were to determine whether the depressant actions of μ-opioid receptor activation on inspiratory activity includes a direct inhibitory action at the inspiratory premotoneuron to XII motoneuron synapse, and to identify underlying mechanism(s). We then examined whether ampakines counteract opioid-induced depression of XII motoneuron activity.

Methodology/Principal Findings

A medullary slice preparation from neonatal rat that produces inspiratory-related output in vitro was used. Measurements of inspiratory burst amplitude and frequency were made from XII nerve roots. Whole-cell patch recordings from XII motoneurons were used to measure membrane currents and synaptic events. Application of the μ-opioid receptor agonist, DAMGO, to the XII nucleus depressed the output of inspiratory XII motoneurons via presynaptic inhibition of excitatory glutamatergic transmission. Ampakines (CX614 and CX717) alleviated DAMGO-induced depression of XII MN activity through postsynaptic actions on XII motoneurons.

Conclusions/Significance

The inspiratory-depressant actions of opioid analgesics include presynaptic inhibition of XII motoneuron output. Ampakines counteract μ-opioid receptor-mediated depression of XII motoneuron inspiratory activity. These results suggest that ampakines may be beneficial in countering opiate-induced suppression of XII motoneuron activity and resultant impairment of airway patency.     

Carotenoid and fatty acid metabolism in light‐stressed Dunaliella salina

β‐Carotene is overproduced in the alga Dunaliella salina in response to high light intensities. We have studied the effects of a sudden light increase on carotenoid and fatty acid metabolism using a flat panel photobioreactor that was run in turbidostat mode to ensure a constant light regime throughout the experiments. Upon the shift to an increased light intensity, β‐carotene production commenced immediately. The first 4 h after induction were marked by constant intracellular levels of β‐carotene (2.2 g LCV^?1), which resulted from identical increases in the production rates of cell volume and β‐carotene. Following this initial phase, β‐carotene productivity continued to increase while the cell volume productivity dropped. As a result, the intracellular β‐carotene concentration increased reaching a maximum of 17 g LCV^?1 after 2 days of light stress. Approximately 1 day before that, the maximum β‐carotene productivity of 30 pg cell^?1 day^?1 (equivalent to 37 mg LRV^?1 day^?1) was obtained, which was about one order of magnitude larger than the average productivity reported for a commercial β‐carotene production facility, indicating a vast potential for improvement. Furthermore, by studying the light‐induced changes in both β‐carotene and fatty acid metabolism, it appeared that carotenoid overproduction was associated with oil globule formation and a decrease in the degree of fatty acid unsaturation. Our results indicate that cellular β‐carotene accumulation in D. salina correlates with accumulation of specific fatty acid species (C16:0 and C18:1) rather than with total fatty acid content. Biotechnol. Bioeng. 2010;106: 638–648. © 2010 Wiley Periodicals, Inc.     

Calling Behavior and Morphology of the Stridulatory Apparatus in Neotropical Grasshoppers (Aleuas Stål; Orthoptera)

The sound production and sound producing apparatus of two species of grasshoppers, A. lineatus Stål, 1878 and A. vitticollis Stål, 1878 (Orthoptera, Acrididae, Copiocerinae) have been studied. For both species oscillograms and other physical data on sounds are presented for the first time. The sound producing behavior is described and the stridulation apparatus mechanism is illustrated. In the case of A. vitticollis these data are the first known on its sound production and general acoustic behavior.     

Gentamicin: use of a programmable calculator to determine dosages from pharmacokinetic data for individual patients.

Gentamicin, an antibiotic frequently used in the treatment of gram-negative infections, has a narrow therapeutic index, so the correct prediction of its serum concentrations is important. Recent studies have emphasized the dubious accuracy of commonly used formulas, and computer programs that provide pharmacokinetic data for individual patients from multiple blood samples have helped to adjust dosages but are expensive. This study tested the applicability of a method using only two blood samples and a programmable calculator to estimate pharmacokinetic parameters for individual patients and adjust dosages to aim at peak and trough serum levels of 6 and 1 micrograms/ml respectively. In the 48 patients with normal renal function this method produced peak serum concentrations of gentamicin within 1 microgram/ml of the desired level in 22 (46%) and therapeutic peak concentrations (between 4 and 10 micrograms/ml) in all the patients. In 10 patients with renal failure it produced peak serum concentrations within 1 microgram/ml of the desired value in 4 and therapeutic serum concentrations in 7. Two patients had peak concentrations below 4 micrograms/ml and one had a peak concentration above 10 micrograms/ml. Two of the three patients whose serum levels were outside the therapeutic range had unstable renal insufficiency. Thus, patients with renal insufficiency need continued monitoring of the serum level of gentamicin, particularly when their renal function is changing.