Phase Dependency of the Human Primary Motor Cortex and Cholinergic Inhibition Cancelation during Beta tACS

The human motor cortex has a tendency to resonant activity at about 20 Hz so stimulation should more readily entrain neuronal populations at this frequency. We investigated whether and how different interneuronal circuits contribute to such resonance by using transcranial magnetic stimulation (TMS) during transcranial alternating current stimulation (tACS) at motor (20 Hz) and a nonmotor resonance frequency (7 Hz). We tested different TMS interneuronal protocols and triggered TMS pulses at different tACS phases. The effect of cholinergic short-latency afferent inhibition (SAI) was abolished by 20 Hz tACS, linking cortical beta activity to sensorimotor integration. However, this effect occurred regardless of the tACS phase. In contrast, 20 Hz tACS selectively modulated MEP size according to the phase of tACS during single pulse, GABAAergic short-interval intracortical inhibition (SICI) and glutamatergic intracortical facilitation (ICF). For SICI this phase effect was more marked during 20 Hz stimulation. Phase modulation of SICI also depended on whether or not spontaneous beta activity occurred at ~20 Hz, supporting an interaction effect between tACS and underlying circuit resonances. The present study provides in vivo evidence linking cortical beta activity to sensorimotor integration, and for beta oscillations in motor cortex being promoted by resonance in GABAAergic interneuronal circuits

Cognitive and behavioral improvement in adults with fragile X syndrome treated with metformin-two cases.

BackgroundThe majority of individuals with fragile X syndrome (FXS) have intellectual disability, behavioral problems, autism, and language deficits. IQ typically declines with age in boys with the full mutation. The results of preclinical studies demonstrated that metformin, a biguanide used to treat type 2 diabetes, rescues multiple phenotypes of FXS in both Drosophila and mouse models. Preliminary studies of patients with FXS demonstrated improvements in behavior.MethodsHere, we present two cases of individuals who have been treated with metformin clinically for one year.ResultsBoth patients demonstrated significant cognitive and behavioral improvements. They also improved eating habits and normalization of their weight percentiles.ConclusionMetformin may be a candidate drug for treatment of several types of symptoms in individuals with FXS

COMPARING PRICES OF BASIC NEEDS (FOODS AND HOUSES): A CASE STUDY OF CHANGLUN, KODIANG AND JITRA

Recently, the price of goods and services including the basic needs (foods and houses) in Malaysia are increasing slightly. Based on random interviews, there are complaints from low level income community of Changlun claiming that the price of basic needs especially foods and houses in Changlun are more expensive than Kodiang and Jitra. The purpose of this community based study is to investigate the claim of the low level income community whom are majority in Changlun. An observational study was conducted for 6 weeks by collecting actual prices of basic needs (foods and houses) in Changlun, Kodiang and Jitra. Exploratory Data Analysis (EDA) was used to compare the prices. The findings indicated that there exist price disparity of basic needs among Changlun, Kodiang and Jitra. Based on the samples taken, Changlun has the highest prices for foods. However, the prices were still within the price range of Kementerian Perdagangan Dalam Negeri, Koperasi dan Kepenggunaan (KPDNKK). Changlun also has the highest house price with the price disparity of RM18,000 and RM90,000 as compared to Jitra and Kodiang respectively. Further investigations needed to collect more data to generalise this issue and before actions can be taken to assist the low level income community in Changlun to cope with the price hike and survive day to day basis.Keywords: Basic needs, prices, communit

Point Mutations in Centromeric Histone Induce Post-zygotic Incompatibility and Uniparental Inheritance.

The centromeric histone 3 variant (CENH3, aka CENP-A) is essential for the segregation of sister chromatids during mitosis and meiosis. To better define CENH3 functional constraints, we complemented a null allele in Arabidopsis with a variety of mutant alleles, each inducing a single amino acid change in conserved residues of the histone fold domain. Many of these transgenic missense lines displayed wild-type growth and fertility on self-pollination, but exhibited frequent post-zygotic death and uniparental inheritance when crossed with wild-type plants. The failure of centromeres marked by these missense mutation in the histone fold domain of CENH3 reproduces the genome elimination syndromes described with chimeric CENH3 and CENH3 from diverged species. Additionally, evidence that a single point mutation is sufficient to generate a haploid inducer provide a simple one-step method for the identification of non-transgenic haploid inducers in existing mutagenized collections of crop species. As proof of the extreme simplicity of this approach to create haploid-inducing lines, we performed an in silico search for previously identified point mutations in CENH3 and identified an Arabidopsis line carrying the A86V substitution within the histone fold domain. This A87V non-transgenic line, while fully fertile on self-pollination, produced postzygotic death and uniparental haploids when crossed to wild type

Massive Star Formation

The enormous radiative and mechanical luminosities of massive stars impact a vast range of scales and processes, from the reionization of the universe, to the evolution of galaxies, to the regulation of the interstellar medium, to the formation of star clusters, and even to the formation of planets around stars in such clusters. Two main classes of massive star formation theory are under active study, Core Accretion and Competitive Accretion. In Core Accretion, the initial conditions are self-gravitating, centrally concentrated cores that condense with a range of masses from the surrounding, fragmenting clump environment. They then undergo relatively ordered collapse via a central disk to form a single star or a small-N multiple. In this case, the pre-stellar core mass function has a similar form to the stellar initial mass function. In Competitive Accretion, the material that forms a massive star is drawn more chaotically from a wider region of the clump without passing through a phase of being in a massive, coherent core. In this case, massive star formation must proceed hand in hand with star cluster formation. If stellar densities become very high near the cluster center, then collisions between stars may also help to form the most massive stars. We review recent theoretical and observational progress towards understanding massive star formation, considering physical and chemical processes, comparisons with low and intermediate-mass stars, and connections to star cluster formation.Comment: Accepted for publication as a chapter in Protostars and Planets VI, University of Arizona Press (2014), eds. H. Beuther, R. Klessen, C. Dullemond, Th. Hennin

Troponin T3 regulates nuclear localization of the calcium channel Cavβ1a subunit in skeletal muscle

The voltage-gated calcium channel (Cav) β1a subunit (Cavβ1a) plays an important role in excitation-contraction coupling (ECC), a process in the myoplasm that leads to muscle-force generation. Recently, we discovered that the Cavβ1a subunit travels to the nucleus of skeletal muscle cells where it helps to regulate gene transcription. To determine how it travels to the nucleus, we performed a yeast two-hybrid screening of the mouse fast skeletal muscle cDNA library and identified an interaction with troponin T3 (TnT3), which we subsequently confirmed by co-immunoprecipitation and co-localization assays in mouse skeletal muscle in vivo and in cultured C2C12 muscle cells. Interacting domains were mapped to the leucine zipper domain in TnT3 COOH-terminus (160-244 aa) and Cavβ1a NH2-terminus (1-99 aa), respectively. The double fluorescence assay in C2C12 cells co-expressing TnT3/DsRed and Cavβ1a/YFP shows that TnT3 facilitates Cavβ1a nuclear recruitment, suggesting that the two proteins play a heretofore unknown role during early muscle differentiation in addition to their classical role in ECC regulation.Fil: Zhang, Tan. Wake Forest School of Medicine; Estados UnidosFil: Taylor, Jackson. Wake Forest School of Medicine; Estados UnidosFil: Jiang, Yang. Wake Forest School of Medicine; Estados UnidosFil: Pereyra, Andrea Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Messi, Maria Laura. Wake Forest School of Medicine; Estados UnidosFil: Wang, Zhong Min. Wake Forest School of Medicine; Estados UnidosFil: Hereñú, Claudia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Delbono, Osvaldo. Wake Forest School of Medicine; Estados Unido

Towards Clinical Use of Engineered Tissues for Cartilage Repair

Osteoarthritis (OA), the most prevalent form of joint disease, afflicts nine percent of the US population over the age of thirty and costs the economy nearly $100 billion annually in healthcare and socioeconomic costs. It is characterized by joint pain and dysfunction, though the pathophysiology remains largely unknown. The progressive loss of cartilage followed by inadequate repair and remodeling of subchondral bone are common hallmarks of this degenerative disease. Due to its avascular nature and limited cellularity, articular cartilage exhibits a poor intrinsic healing response following injury. As such, significant research efforts are aimed at producing engineered cartilage as a cell-based approach for articular cartilage repair. However, the knee joint is mechanically demanding, and during injury, also a milieu of harsh inflammatory agents. The unforgiving mechanochemical environment requires constructs that are capable of bearing such burdens. To this end, previous work in our laboratory has explored the application of stimuli inspired by the native joint environment in attempts to create tissue with functional properties similar to native cartilage so that it may restore loading to the joint. While we have had success at producing these replacement tissues, there is little evidence in the literature that the biological functionality (i.e. response to in vivo-like conditions) of engineered cartilage matches native cartilage. Therefore, in an effort to provide a more complete characterization of the functional nature of developing tissues and facilitate their use clinically, the overarching motivation of the work described in this dissertation is two-fold: 1) characterize the response of engineered cartilage to chemical and mechanical injury; and 2) develop strategies for enhancing the performance and protection of engineered cartilage for in vivo success. Studies in the literature have extensively characterized the effects of wounding to native articular cartilage as well as the effects of an inflammatory environment. For mechanical injuries, cell death is immediate and progressive, ultimately leading to failure of the tissue. Chemical insult has been shown to promote degradation of the matrix components, also leading to failure of the tissue. Under a controlled application of injury (mechanical and chemical), it was found that engineered cartilage, in contrast to native cartilage, has the potential to repair itself following an injury event, as long as there is no catastrophic damage to the matrix. Additionally, when this matrix is intact and well-developed, engineered cartilage constructs exhibit a resistance to degradation, highlighting the potential utility of engineered cartilage as replacement tissues. Enhancing functionality in engineered cartilage was also explored, with the aim of developing strategies to improve, repair, and protect engineered cartilage constructs for their use in vivo. For these purposes, the studies in this dissertation spanned both 2D migration studies to influence the limited wound repair potential of cells as well as 3D culture studies to explore the possibility of protection effects at a tissue level. Together, these models allowed us to capture the complexity needed to fully develop approaches for cartilage repair. Though it has previously been found that applied DC electric fields modulate cell migration, we have developed a novel strategy of employing this technique to screen for desirable populations of cells (those with the greatest capacity for directed migration) to use in cartilage repair. We also found that the AQP1 water channel plays a key role in mechanosensing the extracellular environment, highlighting the potential for its use in therapeutic strategies. For tissue engineering efforts at creating functional cartilage replacement, we uncovered novel strategies to foster better tissue development via co-culture systems and promote the resistance of engineered cartilage to catabolic factors. These findings motivate their potential use in therapeutics and in tissue engineering efforts at creating clinically relevant tissue-engineered constructs for the treatment of OA or following injury. The research described in this dissertation has characterized the biological functionality of engineered tissues and identified strategies for enhancing their use in vivo by modulating the subsequent response to injury, laying the foundation for their use in clinical applications