79 research outputs found

    trans-Acetyldicarbonyl(g5 -cyclopentadienyl)(methyldiphenylphosphane)- molybdenum(II)

    Get PDF
    The title compound, [Mo(C5H5)(C2H3O)(C13H13P)(CO)2], was prepared by reaction of [Mo(CH3)(C5H5)(CO)3] with methyldiphenylphosphane. The MoII atom exhibits a fourlegged piano-stool coordination geometry with the acetyl and phosphane ligands trans to each other. There are several intermolecular C—HO hydrogen-bonding interactions involving carbonyl and acetyl O atoms as acceptors. A close nearly parallel – interaction between the cyclopentadienyl plane and the phenyl ring of the phosphane ligand is present, with an angle of 6.4 (1) between the two least-squares planes. The centroid-to-centroid distance between these groups is 3.772 (3) A˚ , and the closest distance between two atoms of these groups is 3.449 (4) A˚ . Since each Mo complex is engaged in two of these interactions, the complexes form an infinite - stack coincident with the a axis

    Comparison of the adrenalytic activity of mitotane and a methylated homolog on normal adrenal cortex and adrenal cortical carcinoma

    Full text link
    Mitotane is an important adrenalytic drug for the treatment of adrenal cancer whose use is limited by toxicity. Reports from another laboratory indicated that a methylated homolog of Mitotane (Mitometh) tested in guinea pigs possessed comparable adrenalytic activity but was less toxic than Mitotane. This observation prompted us to undertake a comparative study of these two drugs on the basis that Mitometh may be a superior agent for the treatment of adrenal cancer. Preliminary studies in guinea pigs failed to show a significant adrenalytic effect for either Mitotane or Mitometh. Thus, we extended the study to 13 mongrel dogs weighing 12–15 kg that were treated daily with Mitometh or Mitotane (50–100 mg/kg) for 6 or 12 days. Cortisol decreased to undetectable levels and adrenocorticotropic hormone (ACTH) rose to 10 times the baseline levels within 72 h in Mitotane-treated animals. Despite the achievement of similar drug levels, Mitometh treatment in dogs failed to suppress cortisol or increase ACTH. To determine whether these differences were due to differences in bioavailability, we measured the relative concentration of Mitotane and Mitometh in homogenates of adrenal cortex obtained from Mitotane- and Mitometh-treated dogs. The adrenal concentration of Mitometh determined in Mitometh-treated dogs was 5 times higher than the concentration of Mitotane measured in Mitotane-treated animals. Whereas the adrenal glands of Mitotane-treated dogs showed hemorrhage and necrosis, the Mitometh-treated animals showed no adrenal damage. Despite the lack of adrenalytic activity, Mitometh maintained its toxicity as demonstrated by microscopic evidence of hepatic necrosis and an increase in hepatic enzymes. The adrenalytic effects of both agents was also studied in vitro using a human functioning adrenal cortical carcinoma cell line. NCI-H295. Whereas Mitotane strongly suppressed cell growth, Mitometh had a weaker effect. We conclude that Mitometh is not likely to be effective in the therapy of adrenal cancer. Moreover, the results of this study are supportive of the view that metabolic transformation of Mitotane is in some way linked to its adrenalytic action.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46925/1/280_2004_Article_BF00685036.pd

    Everyone on Radio

    Full text link
    This adaptation of Everyman was scheduled for production on the main stage in the Kline Theatre of Gettysburg College. With the onset of COVID-19 and the ensuing advent of distance-learning, that could no longer happen, and originally that was a crushing disappointment. But the show must go on, especially when that show is “Everyman,” an especially apt theatrical choice for a pestilential year. Everyman offers exciting possibilities for audio drama, especially considering the play’s emphasis on the internal struggle of the individual facing death; Everyone on Radio attempts to make the most of these aspects of the play. Never willing to blink in the face of doom, the students in this class rose to the occasion with incredible pluck, optimism, and good humor. In particular, Lauren “Helping” Hand, the peer associate for this year’s course, led the pivot to the podcast platform, and this production is as much hers as anyone’s: She was chief cheerleader, coordinator, and executive producer, in tandem with Joey “Magic Fingers” Maguschak, who acted as senior sound engineer and producer

    Positive Darwinian Selection in the Piston That Powers Proton Pumps in Complex I of the Mitochondria of Pacific Salmon

    Get PDF
    The mechanism of oxidative phosphorylation is well understood, but evolution of the proteins involved is not. We combined phylogenetic, genomic, and structural biology analyses to examine the evolution of twelve mitochondrial encoded proteins of closely related, yet phenotypically diverse, Pacific salmon. Two separate analyses identified the same seven positively selected sites in ND5. A strong signal was also detected at three sites of ND2. An energetic coupling analysis revealed several structures in the ND5 protein that may have co-evolved with the selected sites. These data implicate Complex I, specifically the piston arm of ND5 where it connects the proton pumps, as important in the evolution of Pacific salmon. Lastly, the lineage to Chinook experienced rapid evolution at the piston arm

    Schizophrenia: do all roads lead to dopamine or is this where they start? Evidence from two epidemiologically informed developmental rodent models

    Get PDF
    The idea that there is some sort of abnormality in dopamine (DA) signalling is one of the more enduring hypotheses in schizophrenia research. Opinion leaders have published recent perspectives on the aetiology of this disorder with provocative titles such as ‘Risk factors for schizophrenia—all roads lead to dopamine' or ‘The dopamine hypothesis of schizophrenia—the final common pathway'. Perhaps, the other most enduring idea about schizophrenia is that it is a neurodevelopmental disorder. Those of us that model schizophrenia developmental risk-factor epidemiology in animals in an attempt to understand how this may translate to abnormal brain function have consistently shown that as adults these animals display behavioural, cognitive and pharmacological abnormalities consistent with aberrant DA signalling. The burning question remains how can in utero exposure to specific (environmental) insults induce persistent abnormalities in DA signalling in the adult? In this review, we summarize convergent evidence from two well-described developmental animal models, namely maternal immune activation and developmental vitamin D deficiency that begin to address this question. The adult offspring resulting from these two models consistently reveal locomotor abnormalities in response to DA-releasing or -blocking drugs. Additionally, as adults these animals have DA-related attentional and/or sensorimotor gating deficits. These findings are consistent with many other developmental animal models. However, the authors of this perspective have recently refocused their attention on very early aspects of DA ontogeny and describe reductions in genes that induce or specify dopaminergic phenotype in the embryonic brain and early changes in DA turnover suggesting that the origins of these behavioural abnormalities in adults may be traced to early alterations in DA ontogeny. Whether the convergent findings from these two models can be extended to other developmental animal models for this disease is at present unknown as such early brain alterations are rarely examined. Although it is premature to conclude that such mechanisms could be operating in other developmental animal models for schizophrenia, our convergent data have led us to propose that rather than all roads leading to DA, perhaps, this may be where they start

    Global Analysis of the Evolution and Mechanism of Echinocandin Resistance in Candida glabrata

    Get PDF
    The evolution of drug resistance has a profound impact on human health. Candida glabrata is a leading human fungal pathogen that can rapidly evolve resistance to echinocandins, which target cell wall biosynthesis and are front-line therapeutics for Candida infections. Here, we provide the first global analysis of mutations accompanying the evolution of fungal drug resistance in a human host utilizing a series of C. glabrata isolates that evolved echinocandin resistance in a patient treated with the echinocandin caspofungin for recurring bloodstream candidemia. Whole genome sequencing identified a mutation in the drug target, FKS2, accompanying a major resistance increase, and 8 additional non-synonymous mutations. The FKS2-T1987C mutation was sufficient for echinocandin resistance, and associated with a fitness cost that was mitigated with further evolution, observed in vitro and in a murine model of systemic candidemia. A CDC6-A511G(K171E) mutation acquired before FKS2-T1987C(S663P), conferred a small resistance increase. Elevated dosage of CDC55, which acquired a C463T(P155S) mutation after FKS2-T1987C(S663P), ameliorated fitness. To discover strategies to abrogate echinocandin resistance, we focused on the molecular chaperone Hsp90 and downstream effector calcineurin. Genetic or pharmacological compromise of Hsp90 or calcineurin function reduced basal tolerance and resistance. Hsp90 and calcineurin were required for caspofungin-dependent FKS2 induction, providing a mechanism governing echinocandin resistance. A mitochondrial respiration-defective petite mutant in the series revealed that the petite phenotype does not confer echinocandin resistance, but renders strains refractory to synergy between echinocandins and Hsp90 or calcineurin inhibitors. The kidneys of mice infected with the petite mutant were sterile, while those infected with the HSP90-repressible strain had reduced fungal burden. We provide the first global view of mutations accompanying the evolution of fungal drug resistance in a human host, implicate the premier compensatory mutation mitigating the cost of echinocandin resistance, and suggest a new mechanism of echinocandin resistance with broad therapeutic potential

    The genomic landscape of balanced cytogenetic abnormalities associated with human congenital anomalies

    Get PDF
    Despite the clinical significance of balanced chromosomal abnormalities (BCAs), their characterization has largely been restricted to cytogenetic resolution. We explored the landscape of BCAs at nucleotide resolution in 273 subjects with a spectrum of congenital anomalies. Whole-genome sequencing revised 93% of karyotypes and demonstrated complexity that was cryptic to karyotyping in 21% of BCAs, highlighting the limitations of conventional cytogenetic approaches. At least 33.9% of BCAs resulted in gene disruption that likely contributed to the developmental phenotype, 5.2% were associated with pathogenic genomic imbalances, and 7.3% disrupted topologically associated domains (TADs) encompassing known syndromic loci. Remarkably, BCA breakpoints in eight subjects altered a single TAD encompassing MEF2C, a known driver of 5q14.3 microdeletion syndrome, resulting in decreased MEF2C expression. We propose that sequence-level resolution dramatically improves prediction of clinical outcomes for balanced rearrangements and provides insight into new pathogenic mechanisms, such as altered regulation due to changes in chromosome topology

    Accelerated surgery versus standard care in hip fracture (HIP ATTACK): an international, randomised, controlled trial

    Get PDF

    Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials

    Get PDF
    An amendment to this paper has been published and can be accessed via the original article
    • 

    corecore