Ras homolog gene family H (RhoH) deficiency induces psoriasis-like chronic dermatitis by promoting TH17 cell polarization

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Studies on homologous recombination in the green alga Chlamydomonas reinhardtii

The introduction of exogenous DNA into the nuclear genome of Chlamydomonas reinhardtii occurs predominantly via non-homologous (illegitimate) recombination and results in integration at apparently-random loci. Using truncated and modified versions of the C. reinhardtii ARG7 gene in a series of transformation experiments, we demonstrate that homologous recombination between introduced DNA molecules occurs readily in C. reinhardtii, requires a region of homology of no more than 230 bp, and gives rise to intact copies of ARG7 in the nuclear genome. Evidence is presented for homologous recombination between introduced ARG7 DNA and the resident copy of the gene, and for the de-novo synthesis of the ARG7 sequence during transformation.     

Isokinematic muscle mechanics in four groups of women of increasing age

Summary The purpose of this study was to evaluate the effects of age on dynamic muscle attributes of the knee extensors and flexors in postmenopausal women. Young healthy women (3rd decade,n = 15; 4th decade,n = 5) and older healthy women (6th decade,n = 9; 7th decade,n = 6) were tested at six angular velocities from 60° · s^–1 to 400° · s^–1. The 3rd and 4th decade groups produced greater extensor and flexor values for strength related variables at all angular velocities (peak torque, angle specific torque, work, power) than both the 6th and 7th decade groups (P<0.05). However, relative changes in these variables, with increments in angular velocity, were equivalent among the groups. Analysis of the flexor: extensor ratios for these variables demonstrated a differential loss in flexor function with increased age, perhaps indicative of type II motor unit loss or muscle fibre atrophy. It is suggested that such changes may be present even within 4th decade subjects.     

EMG power spectra of elbow extensors during ramp and step isometric contractions

Summary The goal of the present study was to compare electromyogram (EMG) power spectra obtained from step (constant force level) and ramp (progressive increase in the force level) isometric contractions. Data windows of different durations were also analysed for the step contractions, in order to evaluate the stability of EMG power spectrum statistics. Fourteen normal subjects performed (1) five ramp elbow extensions ranging from 0 to 100% of the maximum voluntary contraction (MVC) and (2) three stepwise elbow extensions maintained at five different levels of MVC. Spectral analysis of surface EMG signals obtained from triceps brachii and anconeus was performed. The mean power frequency (MPF) and the median frequency (MF) of each power spectrum were obtained from 256-ms windows taken at 10, 20, 40, 60 and 80% MVC for each type of contraction and in addition on 512-, 1024-and 2048-ms windows for the step contractions. No significant differences (P>0.05) were found in the values of both spectral statistics between the different window lengths. Even though no significant differences (P>0.05) were found between the ramp and the step contractions, significant interactions (P<0.05) between these two types of contraction and the force level were found for both the MPF and the MF data. These interactions point out the existence of different behaviours for both the MPF and the MF across force levels between the two types of contraction.     

Expression of inducible nitric oxide synthase induced by lipid-associated membrane proteins of Ureaplasma urealyticum is regulated by nuclear factor κB-mediated mechanism in murine macrophages

U.urealyticumisthesmallestprokaryoticorgan ismcapableofself replication.Thetinymicroor ganismcouldbeisolatedfromurogenital,placen tasandtherespiratorytractsofpreterminfants.Moreover,U.urealyticuminfectionmaybein volvedinnon specificurethritis(NSU),prostati tis,postpartumfever,infertility,pelvicinflamma torydisease,neonatalpneumoniaandevenchronic lungdisease(CLD)[1].ItisknownthatU.urealyticumlackscellwallstructureandcontains abundantmembraneproteins,butitspathogenicity isstillunknownclearly.…     

Radiotelemetry recording of electroencephalogram in piglets during rest

A wireless recording system was developed to study the electroencephalogram (EEG) in unrestrained, male Landrace piglets. Under general anesthesia, ball-tipped silver/silver chloride electrodes for EEG recording were implanted onto the dura matter of the parietal and frontal cortex of the piglets. A pair of miniature preamplifiers and transmitters was then mounted on the surface of the skull. To examine whether other bioelectrical activities interfere with the EEG measurements, an electrocardiogram (ECG) or electromyogram (EMG) of the neck was simultaneously recorded with the EEG. Next, wire electrodes for recording movement of the eyelid were implanted with EEG electrodes, and EEG and eyelid movements were simultaneously measured. Power spectral analysis using a Fast Fourier Transformation (FFT) algorithm indicates that EEG was successfully recorded in unrestrained piglets, at rest, during the daytime in the absence of interference from ECG, EMG or eyelid movements. These data indicate the feasibility of using our radiotelemetry system for measurement of EEG under these conditions.     

The innate immune response under the control of the LXR pathway

Macrophages play essential roles in infection and resolution of inflammation. This review summarizes recent findings that suggest a relevant role for the nuclear receptor liver X receptor (LXR) in the evolution of immune responses. By exerting both positive and negative regulation of specific macrophage gene expression networks, LXRs display anti-inflammatory activities and promote macrophage survival in bacterial infection settings. Agonists that activate the LXR pathway may be used to enhance innate immunity to highly virulent pathogens that otherwise induce macrophage apoptosis as a means to subvert host immune defense.     

Effect of relaxation training on cardiac parasympathetic tone

To examine the hypothesis that the relaxation response is associated with an increase in cardiac parasympathetic tone, the frequency components of heart rate variability during relaxation training were investigated in 16 college students. Electrocardiograms and pneumograms were recorded during a 5-min baseline period followed by three successive 5-min sessions of the autogenic training (relaxation) or by the same periods of quiet rest (control), while subjects breathed synchronously with a visual pacemaker (0.25 Hz). Although neither the magnitude nor the frequeney of respiration showed a significant difference between relaxation and control, the amplitude of the high-frequency component of heart rate variability increased only during relaxation (p= .008). There was no significant difference in the ratio of the low-frequency (0.04–0.15 Hz) to the high-frequency amplitudes. The increased high-frequency amplitude without changes in the respiratory parameters indicates enhanced cardiac parasympathetic tone. Thus, our results support the initial hypothesis of this study. Enhanced cardiac parasympathetic tone may explain an important mechanism underlying the beneficial effect of the relaxation response.     

HnRNP CBP35-CBP67 interaction during stress response and ageing

Previous studies have demonstrated the existence of nuclear carbohydrate binding proteins in a variety of mammalian cells with molecular masses of 35 000, 67 000, and 70 000 (CBP35, CBP67, and CBP70), which are associated with nuclear ribonucleoprotein (RNP) complexes. CBP35 consists of two domains, an aminoterminal portion that is homologous to certain regions of proteins of the heterogeneous nuclear RNP complex, and a carboxyl-terminal portion homologous to β-galactoside-specific lectins. CBP35 it has been proposed, like the glucose-specific lectin, CBP67, to guide RNP complexes through the nuclear pore. Here we show that the exposure of mature rats to stress induces an increase in nuclear CBP35 bound to CBP67 and retained on immobilized glucose. Nuclear extracts from the livers of old rats displayed no detectable stress response. This CBP35·CBP67 association detected in rat liver is considered with respect to the CBP35·CBP70 association recently observed in HL60 cell nuclear extracts.