Discovery of a hepatitis C target and its pharmacological inhibitors by microfluidic affinity analysis

More effective therapies are urgently needed against hepatitis C virus (HCV), a major cause of viral hepatitis. We used in vitro protein expression and microfluidic affinity analysis to study RNA binding by the HCV transmembrane protein NS4B, which plays an essential role in HCV RNA replication. We show that HCV NS4B binds RNA and that this binding is specific for the 3' terminus of the negative strand of the viral genome with a dissociation constant (K(d)) of approximately 3.4 nM. A high-throughput microfluidic screen of a compound library identified 18 compounds that substantially inhibited binding of RNA by NS4B. One of these compounds, clemizole hydrochloride, was found to inhibit HCV RNA replication in cell culture that was mediated by its suppression of NS4B's RNA binding, with little toxicity for the host cell. These results yield new insight into the HCV life cycle and provide a candidate compound for pharmaceutical development

Does the lateral intercondylar ridge disappear in ACL deficient patients?

The aim of this study was to determine whether there is a difference in the presence of the lateral intercondylar ridge and the lateral bifurcate ridge between patients with sub-acute and chronic ACL injuries. We hypothesized that the ridges would be present less often with chronic ACL deficiency. Twenty-five patients with a chronic ACL injury were matched for age and gender to 25 patients with a sub-acute ACL injury. The lateral intercondylar ridge and lateral bifurcate ridge were scored as either present, absent, or indeterminate due to insufficient visualization by three blinded observers. The kappa for the three observers was .61 for the lateral intercondylar ridge and .58 for the lateral bifurcate ridge. The lateral intercondylar ridge was present in 88% of the sub-acute patients and 88% of the chronic patients. The lateral bifurcate ridge was present in 48% of the sub-acute and 48% of the chronic patients. This matched-pairs case–control study was unable to show a difference in the presence of the femoral bony ridges between patients with acute and chronic ACL injuries. The authors would suggest looking for the ridges as a landmark of the native ACL insertion site during ACL reconstruction in both acute and chronic ACL injuries

Smyd3 Is Required for the Development of Cardiac and Skeletal Muscle in Zebrafish

Modifications of histone tails are involved in the regulation of a wide range of biological processes including cell cycle, cell survival, cell division, and cell differentiation. Among the modifications, histone methylation plays a critical role in cardiac and skeletal muscle differentiation. In our earlier studies, we found that SMYD3 has methyltransferase activity to histone H3 lysine 4, and that its up-regulation is involved in the tumorigenesis of human colon, liver, and breast. To clarify the role of Smyd3 in development, we have studied its expression patterns in zebrafish embryos and the effect of its suppression on development using Smyd3-specific antisense morpholino-oligonucleotides. We here show that transcripts of smyd3 were expressed in zebrafish embryos at all developmental stages examined and that knockdown of smyd3 in embryos resulted in pericardial edema and defects in the trunk structure. In addition, these phenotypes were associated with abnormal expression of three heart-chamber markers including cmlc2, amhc and vmhc, and abnormal expression of myogenic regulatory factors including myod and myog. These data suggest that Smyd3 plays an important role in the development of heart and skeletal muscle

A novel WFS1 mutation in a family with dominant low frequency sensorineural hearing loss with normal VEMP and EcochG findings

Background: Low frequency sensorineural hearing loss (LFSNHL) is an uncommon clinical finding. Mutations within three different identified genes (DIAPH1, MYO7A, and WFS1) are known to cause LFSNHL. The majority of hereditary LFSNHL is associated with heterozygous mutations in the WFS1 gene (wolframin protein). The goal of this study was to use genetic analysis to determine if a small American family's hereditary LFSNHL is linked to a mutation in the WFS1 gene and to use VEMP and EcochG testing to further characterize the family's audiovestibular phenotype. Methods: The clinical phenotype of the American family was characterized by audiologic testing, vestibular evoked myogenic potentials (VEMP), and electrocochleography (EcochG) evaluation. Genetic characterization was performed by microsatellite analysis and direct sequencing of WFS1 for mutation detection. Results: Sequence analysis of the WFS1 gene revealed a novel heterozygous mutation at c.2054G>C predicting a p.R685P amino acid substitution in wolframin. The c.2054G>C mutation segregates faithfully with hearing loss in the family and is absent in 230 control chromosomes. The p.R685 residue is located within the hydrophilic C-terminus of wolframin and is conserved across species. The VEMP and EcochG findings were normal in individuals segregating the WFS1 c.2054G>C mutation. Conclusion: We discovered a novel heterozygous missense mutation in exon 8 of WFS1 predicting a p.R685P amino acid substitution that is likely to underlie the LFSNHL phenotype in the American family. For the first time, we describe VEMP and EcochG findings for individuals segregating a heterozygous WFS1 mutation.NIH grants DC04945 (V.A.S), DC006901 (V.A.S.) and P30 DC04661 (V.M. Bloedel Core)

On systems and control approaches to therapeutic gain

BACKGROUND: Mathematical models of cancer relevant processes are being developed at an increasing rate. Conceptual frameworks are needed to support new treatment designs based on such models. METHODS: A modern control perspective is used to formulate two therapeutic gain strategies. RESULTS: Two conceptually distinct therapeutic gain strategies are provided. The first is direct in that its goal is to kill cancer cells more so than normal cells, the second is indirect in that its goal is to achieve implicit therapeutic gains by transferring states of cancer cells of non-curable cases to a target state defined by the cancer cells of curable cases. The direct strategy requires models that connect anti-cancer agents to an endpoint that is modulated by the cause of the cancer and that correlates with cell death. It is an abstraction of a strategy for treating mismatch repair (MMR) deficient cancers with iodinated uridine (IUdR); IU-DNA correlates with radiation induced cell killing and MMR modulates the relationship between IUdR and IU-DNA because loss of MMR decreases the removal of IU from the DNA. The second strategy is indirect. It assumes that non-curable patient outcomes will improve if the states of their malignant cells are first transferred toward a state that is similar to that of a curable patient. This strategy is difficult to employ because it requires a model that relates drugs to determinants of differences in patient survival times. It is an abstraction of a strategy for treating BCR-ABL pro-B cell childhood leukemia patients using curable cases as the guides. CONCLUSION: Cancer therapeutic gain problem formulations define the purpose, and thus the scope, of cancer process modeling. Their abstractions facilitate considerations of alternative treatment strategies and support syntheses of learning experiences across different cancers

The meaning and measurement of implementation climate

<p>Abstract</p> <p>Background</p> <p>Climate has a long history in organizational studies, but few theoretical models integrate the complex effects of climate during innovation implementation. In 1996, a theoretical model was proposed that organizations could develop a positive climate for implementation by making use of various policies and practices that promote organizational members' means, motives, and opportunities for innovation use. The model proposes that implementation climate--or the extent to which organizational members perceive that innovation use is expected, supported, and rewarded--is positively associated with implementation effectiveness. The implementation climate construct holds significant promise for advancing scientific knowledge about the organizational determinants of innovation implementation. However, the construct has not received sufficient scholarly attention, despite numerous citations in the scientific literature. In this article, we clarify the meaning of implementation climate, discuss several measurement issues, and propose guidelines for empirical study.</p> <p>Discussion</p> <p>Implementation climate differs from constructs such as organizational climate, culture, or context in two important respects: first, it has a strategic focus (implementation), and second, it is innovation-specific. Measuring implementation climate is challenging because the construct operates at the organizational level, but requires the collection of multi-dimensional perceptual data from many expected innovation users within an organization. In order to avoid problems with construct validity, assessments of within-group agreement of implementation climate measures must be carefully considered. Implementation climate implies a high degree of within-group agreement in climate perceptions. However, researchers might find it useful to distinguish implementation climate level (the average of implementation climate perceptions) from implementation climate strength (the variability of implementation climate perceptions). It is important to recognize that the implementation climate construct applies most readily to innovations that require collective, coordinated behavior change by many organizational members both for successful implementation and for realization of anticipated benefits. For innovations that do not possess these attributes, individual-level theories of behavior change could be more useful in explaining implementation effectiveness.</p> <p>Summary</p> <p>This construct has considerable value in implementation science, however, further debate and development is necessary to refine and distinguish the construct for empirical use.</p

Experimental Microbial Evolution of Extremophiles

Experimental microbial evolutions (EME) involves studying closely a microbial population after it has been through a large number of generations under controlled conditions (Kussell 2013). Adaptive laboratory evolution (ALE) selects for fitness under experimentally imposed conditions (Bennett and Hughes 2009; Dragosits and Mattanovich 2013). However, experimental evolution studies focusing on the contributions of genetic drift and natural mutation rates to evolution are conducted under non-selective conditions to avoid changes imposed by selection (Hindré et al. 2012). To understand the application of experimental evolutionary methods to extremophiles it is essential to consider the recent growth in this field over the last decade using model non-extremophilic microorganisms. This growth reflects both a greater appreciation of the power of experimental evolution for testing evolutionary hypotheses and, especially recently, the new power of genomic methods for analyzing changes in experimentally evolved lineages. Since many crucial processes are driven by microorganisms in nature, it is essential to understand and appreciate how microbial communities function, particularly with relevance to selection. However, many theories developed to understand microbial ecological patterns focus on the distribution and the structure of diversity within a microbial population comprised of single species (Prosser et al. 2007). Therefore an understanding of the concept of species is needed. A common definition of species using a genetic concept is a group of interbreeding individuals that is isolated from other such groups by barriers of recombination (Prosser et al. 2007). An alternative ecological species concept defines a species as set of individuals that can be considered identical in all relevant ecological traits (Cohan 2001). This is particularly important because of the abundance and deep phylogenetic complexity of microbial communities. Cohan postulated that “bacteria occupy discrete niches and that periodic selection will purge genetic variation within each niche without preventing divergence between the inhabitants of different niches”. The importance of gene exchange mechanisms likely in bacteria and archaea and therefore extremophiles, arises from the fact that their genomes are divided into two distinct parts, the core genome and the accessory genome (Cohan 2001). The core genome consists of genes that are crucial for the functioning of an organism and the accessory genome consists of genes that are capable of adapting to the changing ecosystem through gain and loss of function. Strains that belong to the same species can differ in the composition of accessory genes and therefore their capability to adapt to changing ecosystems (Cohan 2001; Tettelin et al. 2005; Gill et al. 2005). Additional ecological diversity exists in plasmids, transposons and pathogenicity islands as they can be easily shared in a favorable environment but still be absent in the same species found elsewhere (Wertz et al. 2003). This poses a major challenge for studying ALE and community microbial ecology indicating a continued need to develop a fitting theory that connects the fluid nature of microbial communities to their ecology (Wertz et al. 2003; Coleman et al. 2006). Understanding the nature and contribution of different processes that determine the frequencies of genes in any population is the biggest concern in population and evolutionary genetics (Prosser et al. 2007) and it is critical for an understanding of experimental evolution

Exploring Predictors of Outcome in the Psychosis Prodrome: Implications for Early Identification and Intervention

Functional disability is a key component of many psychiatric illnesses, particularly schizophrenia. Impairments in social and role functioning are linked to cognitive deficits, a core feature of psychosis. Retrospective analyses demonstrate that substantial functional decline precedes the onset of psychosis. Recent investigations reveal that individuals at clinical-high-risk (CHR) for psychosis show impairments in social relationships, work/school functioning and daily living skills. CHR youth also demonstrate a pattern of impairment across a range of cognitive domains, including social cognition, which is qualitatively similar to that of individuals with schizophrenia. While many studies have sought to elucidate predictors of clinical deterioration, specifically the development of schizophrenia, in such CHR samples, few have investigated factors relevant to psychosocial outcome. This review integrates recent findings regarding cognitive and social-cognitive predictors of outcome in CHR individuals, and proposes potential directions for future research that will contribute to targeted interventions and improved outcome for at-risk youth