1,030 research outputs found
Guanine a-carboxy nucleoside phosphonate (G-a-CNP) shows a different inhibitory kinetic profile against the DNA polymerases of human immunodeficiency virus (HIV) and herpes viruses
Îą-Carboxy nucleoside phosphonates (Îą-CNPs) are modified nucleotides that represent a novel class of nucleotide-competing reverse transcriptase (RT) inhibitors (NcRTIs). They were designed to act directly against HIV-1 RT without the need for prior activation (phosphorylation). In this respect, they differ from the nucleoside or nucleotide RTIs [N(t)RTIs] that require conversion to their triphosphate forms before being inhibitory to HIV-1 RT. The guanine derivative (G-Îą-CNP) has now been synthesized and investigated for the first time. The (L)-(+)-enantiomer of G-Îą-CNP directly and competitively inhibits HIV-1 RT by interacting with the substrate active site of the enzyme. The (D)-(â)-enantiomer proved inactive against HIV-1 RT. In contrast, the (+)- and (â)-enantiomers of G-Îą-CNP inhibited herpes (i.e. HSV-1, HCMV) DNA polymerases in a non- or uncompetitive manner, strongly indicating interaction of the (L)-(+)- and the (D)-(â)-G-Îą-CNPs at a location different from the polymerase substrate active site of the herpes enzymes. Such entirely different inhibition profile of viral polymerases is unprecedented for a single antiviral drug molecule. Moreover, within the class of Îą-CNPs, subtle differences in their sensitivity to mutant HIV-1 RT enzymes were observed depending on the nature of the nucleobase in the Îą-CNP molecules. The unique properties of the Îą-CNPs make this class of compounds, including G-Îą-CNP, direct acting inhibitors of multiple viral DNA polymerases
Functional characterization of C. elegans Y-box-binding proteins reveals tissue-specific functions and a critical role in the formation of polysomes
The cold shock domain is one of the most highly conserved motifs between bacteria and higher eukaryotes. Y-box-binding proteins represent a subfamily of cold shock domain proteins with pleiotropic functions, ranging from transcription in the nucleus to translation in the cytoplasm. These proteins have been investigated in all major model organisms except Caenorhabditis elegans. In this study, we set out to fill this gap and present a functional characterization of CEYs, the C. elegans Y-box-binding proteins. We find that, similar to other organisms, CEYs are essential for proper gametogenesis. However, we also report a novel function of these proteins in the formation of large polysomes in the soma. In the absence of the somatic CEYs, polysomes are dramatically reduced with a simultaneous increase in monosomes and disomes, which, unexpectedly, has no obvious impact on animal biology. Because transcripts that are enriched in polysomes in wild-type animals tend to be less abundant in the absence of CEYs, our findings suggest that large polysomes might depend on transcript stabilization mediated by CEY protein
Management of histoplasmosis by infectious disease physicians
BACKGROUND: The Infectious Diseases Society of America (IDSA) guidelines for the management of histoplasmosis were last revised 15 years ago. Since those guidelines were compiled, new antifungal treatment options have been developed. Furthermore, the ongoing development of immunomodulatory therapies has increased the population at increased risk to develop histoplasmosis.
METHODS: An electronic survey about the management practices of histoplasmosis was distributed to the adult infectious disease (ID) physician members of the IDSA\u27s Emerging Infections Network.
RESULTS: The survey response rate was 37% (551/1477). Only 46% (253/551) of respondents reported seeing patients with histoplasmosis. Regions considered endemic had 82% (158/193) of physicians report seeing patients with histoplasmosis compared to 27% (95/358) of physicians in regions not classically considered endemic (
CONCLUSIONS: Though there are increased reports of histoplasmosis diagnoses outside regions classically considered endemic, a majority of ID physicians reported not seeing patients with histoplasmosis. Most respondents reported adherence to IDSA guidelines recommending itraconazole in each clinical situation. New histoplasmosis guidelines need to reflect the growing need for updated general guidance, particularly for immunocompromised populations
Factors in patientsâ experience of hospital care: Evidence from California, 2009â2011
The use of measures of patient-centered care to evaluate hospital care is mandated by The Patient Protection and Affordable Care Act of 2010. Using three years of data from 315 California acute-care hospitals and data collected from patients via the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey, we seek to evaluate patientsâ hospital-care experience by (1) analyzing patientsâ experience-of-care scores in light of these hospitalsâ patient profiles, structural characteristics, and outcomes in 2011, and (2) determining and analyzing the extent of changes in patientsâ experience of care over the three-year period 2009â2011. For 2011, we find significant variation in patientsâ experience-of-care scores associated with hospitalsâ different patient profiles and structural characteristics. In spite of these single-year differences, virtually all aspects of patientsâ experience of care showed improvement over the 2009-2011 period
The effect of polyploidy and hybridization on the evolution of floral colour in Nicotiana (Solanaceae)
Background and Aims: We investigate whether changes in floral colour accompany polyploid and homoploid hybridisation, important processes in angiosperm evolution.
Potentially, changes in floral colour can facilitate speciation through pollinator shifts.
Methods: We examined spectral reflectance of corolla tissue from 60 Nicotiana (Solanaceae) accessions (41 taxa) based on spectral shape (corresponding to pigmentation) as well as bee and hummingbird colour perception to assess patterns of floral colour evolution. We compared polyploid and homoploid hybrid spectra to those of their progenitors to evaluate whether hybridisation has resulted in floral
colour shifts.
Key Results: Floral colour categories in Nicotiana seem to have arisen multiple times independently during the evolution of the genus. Polyploid and homoploid hybrids
can display a floral colour: 1) intermediate between progenitors, 2) like one or other progenitor, or 3) a transgressive or divergent colour not present in either progenitor.
Conclusions: Floral colour evolution in Nicotiana is weakly constrained by phylogeny, but colour shifts occur and are sometimes associated with allopolyploid or homoploid speciation. Transgressive floral colour in N. tabacum has arisen by inheritance of anthocyanin pigmentation from its paternal progenitor while having a plastid phenotype like its maternal progenitor. Potentially, floral colour evolution has been driven by, or resulted in, pollinator shifts
Morphological Alternations at the Intonational Phrase Edge
This article develops an analysis of a pair of morphological alternations in K\u27ichee\u27 (Mayan) that are conditioned at the right edge of intonational phrase boundaries. I propose a syntax-prosody mapping algorithm that derives intonational phrase boundaries from the surface syntax, and then argue that each alternation can be understood in terms of output optimization. The important fact is that a prominence peak is always rightmost in the intonational phrase, and so the morphological alternations occur in order to ensure an optimal host for this prominence peak. Finally, I consider the wider implications of the analysis for the architecture of the syntax-phonology interface, especially as it concerns late-insertion theories of morphology
No Evidence for XMRV in German CFS and MS Patients with Fatigue Despite the Ability of the Virus to Infect Human Blood Cells In Vitro
BACKGROUND: Xenotropic murine leukemia virus-related virus (XMRV), a novel human retrovirus originally identified in prostate cancer tissues, has recently been associated with chronic fatigue syndrome (CFS), a disabling disease of unknown etiology affecting millions of people worldwide. However, several subsequent studies failed to detect the virus in patients suffering from these illnesses or in healthy subjects. Here we report the results of efforts to detect antibody responses and viral sequences in samples from a cohort of German CFS and relapsing remitting multiple sclerosis (MS) patients with fatigue symptoms. METHODOLOGY: Blood samples were taken from a cohort of 39 patients fulfilling the Fukuda/CDC criteria (CFS), from 112 patients with an established MS diagnosis and from 40 healthy donors. Fatigue severity in MS patients was assessed using the Fatigue Severity Scale (FSS). Validated Gag- and Env-ELISA assays were used to screen sera for XMRV antibodies. PHA-activated PBMC were cultured for seven days in the presence of IL-2 and DNA isolated from these cultures as well as from co-cultures of PBMC and highly permissive LNCaP cells was analyzed by nested PCR for the presence of the XMRV gag gene. In addition, PBMC cultures were exposed to 22Rv1-derived XMRV to assess infectivity and virus production. CONCLUSION: None of the screened sera from CFS and MS patients or healthy blood donors tested positive for XMRV specific antibodies and all PBMC (and PBMC plus LNCaP) cultures remained negative for XMRV sequences by nested PCR. These results argue against an association between XMRV infection and CFS and MS in Germany. However, we could confirm that PBMC cultures from healthy donors and from CFS patients can be experimentally infected by XMRV, resulting in the release of low levels of transmittable virus
Developing a competency framework for the initial training of educational psychologists working with young people aged 16-25
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The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer.
Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM -/- patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (ORâ=â2.44, Pâ=â0.034 and ORâ=â3.79; Pâ=â0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (ORâ=â1.96; Pâ=â0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
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