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1.
J Appl Psychol ; 108(12): 1998-2017, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37498709

ABSTRACT

Unit human capital resources (HCR) are vital to performance across organizational levels. Crucially, the benefits of unit HCR often hinge on resource access and effective resource management. Yet, how units manage HCR remains unclear. We first review findings from human resource management (HRM) and unit leadership literatures relating to unit HCR, which have evolved separately despite their shared goals. Using our review as a foundation, we offer an integrative model highlighting the ways unit leaders can leverage HRM practices and their leadership behaviors for the greatest impact on unit HCR. In so doing, we identify a potentially potent nexus for scholars of both disciplines to focus their integrative efforts on-unit leaders-given their responsibility for HRM practice delivery (e.g., implementing a job rotation program) and their own leadership behaviors (e.g., composing teams). We conclude by highlighting future research questions, opportunities for theoretical integration, and expanding empirical examination. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Subject(s)
Leadership , Social Behavior , Humans , Workforce
2.
bioRxiv ; 2023 Mar 23.
Article in English | MEDLINE | ID: mdl-36993449

ABSTRACT

Prostate cancer (PCa) is the second leading cause of cancer death for men in the United States. While organ-confined disease has reasonable expectation of cure, metastatic PCa is universally fatal upon recurrence during hormone therapy, a stage termed castration-resistant prostate cancer (CRPC). Until such time as molecularly defined subtypes can be identified and targeted using precision medicine, it is necessary to investigate new therapies that may apply to the CRPC population as a whole. The administration of ascorbate, more commonly known as ascorbic acid or Vitamin C, has proved lethal to and highly selective for a variety of cancer cell types. There are several mechanisms currently under investigation to explain how ascorbate exerts anti-cancer effects. A simplified model depicts ascorbate as a pro-drug for reactive oxygen species (ROS), which accumulate intracellularly and generate DNA damage. It was therefore hypothesized that poly(ADP-ribose) polymerase (PARP) inhibitors, by inhibiting DNA damage repair, would augment the toxicity of ascorbate. Results: Two distinct CRPC models were found to be sensitive to physiologically relevant doses of ascorbate. Moreover, additional studies indicate that ascorbate inhibits CRPC growth in vitro via multiple mechanisms including disruption of cellular energy dynamics and accumulation of DNA damage. Combination studies were performed in CRPC models with ascorbate in conjunction with escalating doses of three different PARP inhibitors (niraparib, olaparib, and talazoparib). The addition of ascorbate augmented the toxicity of all three PARP inhibitors and proved synergistic with olaparib in both CRPC models. Finally, the combination of olaparib and ascorbate was tested in vivo in both castrated and non-castrated models. In both cohorts, the combination treatment significantly delayed tumor growth compared to monotherapy or untreated control. Conclusions: These data indicate that pharmacological ascorbate is an effective monotherapy at physiological concentrations and kills CRPC cells. Ascorbate-induced tumor cell death was associated with disruption of cellular energy dynamics and accumulation of DNA damage. The addition of PARP inhibition increased the extent of DNA damage and proved effective at slowing CRPC growth both in vitro and in vivo. These findings nominate ascorbate and PARPi as a novel therapeutic regimen that has the potential to improve CRPC patient outcomes.

3.
Clin Cancer Res ; 28(7): 1446-1459, 2022 04 01.
Article in English | MEDLINE | ID: mdl-35078861

ABSTRACT

PURPOSE: DNA-dependent protein kinase catalytic subunit (DNA-PKcs, herein referred as DNA-PK) is a multifunctional kinase of high cancer relevance. DNA-PK is deregulated in multiple tumor types, including prostate cancer, and is associated with poor outcomes. DNA-PK was previously nominated as a therapeutic target and DNA-PK inhibitors are currently undergoing clinical investigation. Although DNA-PK is well studied in DNA repair and transcriptional regulation, much remains to be understood about the way by which DNA-PK drives aggressive disease phenotypes. EXPERIMENTAL DESIGN: Here, unbiased proteomic and metabolomic approaches in clinically relevant tumor models uncovered a novel role of DNA-PK in metabolic regulation of cancer progression. DNA-PK regulation of metabolism was interrogated using pharmacologic and genetic perturbation using in vitro cell models, in vivo xenografts, and ex vivo in patient-derived explants (PDE). RESULTS: Key findings reveal: (i) the first-in-field DNA-PK protein interactome; (ii) numerous DNA-PK novel partners involved in glycolysis; (iii) DNA-PK interacts with, phosphorylates (in vitro), and increases the enzymatic activity of glycolytic enzymes ALDOA and PKM2; (iv) DNA-PK drives synthesis of glucose-derived pyruvate and lactate; (v) DNA-PK regulates glycolysis in vitro, in vivo, and ex vivo; and (vi) combination of DNA-PK inhibitor with glycolytic inhibitor 2-deoxyglucose leads to additive anti-proliferative effects in aggressive disease. CONCLUSIONS: Findings herein unveil novel DNA-PK partners, substrates, and function in prostate cancer. DNA-PK impacts glycolysis through direct interaction with glycolytic enzymes and modulation of enzymatic activity. These events support energy production that may contribute to generation and/or maintenance of DNA-PK-mediated aggressive disease phenotypes.


Subject(s)
DNA-Activated Protein Kinase , Prostatic Neoplasms, Castration-Resistant , DNA , DNA-Activated Protein Kinase/genetics , DNA-Activated Protein Kinase/metabolism , Glycolysis , Humans , Male , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/genetics , Proteomics , Pyruvate Kinase/metabolism
4.
Nat Commun ; 10(1): 2276, 2019 05 23.
Article in English | MEDLINE | ID: mdl-31123312

ABSTRACT

Solar flares often involve the acceleration of particles to relativistic energies and the generation of high-intensity bursts of radio emission. In some cases, the radio bursts can show periodic or quasiperiodic intensity pulsations. However, precisely how these pulsations are generated is still subject to debate. Prominent theories employ mechanisms such as periodic magnetic reconnection, magnetohydrodynamic (MHD) oscillations, or some combination of both. Here we report on high-cadence (0.25 s) radio imaging of a 228 MHz radio source pulsating with a period of 2.3 s during a solar flare on 2014-April-18. The pulsating source is due to an MHD sausage mode oscillation periodically triggering electron acceleration in the corona. The periodic electron acceleration results in the modulation of a loss-cone instability, ultimately resulting in pulsating plasma emission. The results show that a complex combination of MHD oscillations and plasma instability modulation can lead to pulsating radio emission in astrophysical environments.

5.
Nat Commun ; 1: 74, 2010 Sep 21.
Article in English | MEDLINE | ID: mdl-20865805

ABSTRACT

Solar coronal mass ejections (CMEs) are the most significant drivers of adverse space weather on Earth, but the physics governing their propagation through the heliosphere is not well understood. Although stereoscopic imaging of CMEs with NASA's Solar Terrestrial Relations Observatory (STEREO) has provided some insight into their three-dimensional (3D) propagation, the mechanisms governing their evolution remain unclear because of difficulties in reconstructing their true 3D structure. In this paper, we use a new elliptical tie-pointing technique to reconstruct a full CME front in 3D, enabling us to quantify its deflected trajectory from high latitudes along the ecliptic, and measure its increasing angular width and propagation from 2 to 46 (∼0.2 AU). Beyond 7 , we show that its motion is determined by an aerodynamic drag in the solar wind and, using our reconstruction as input for a 3D magnetohydrodynamic simulation, we determine an accurate arrival time at the Lagrangian L1 point near Earth.

6.
Bioorg Med Chem ; 15(2): 616-25, 2007 Jan 15.
Article in English | MEDLINE | ID: mdl-17123820

ABSTRACT

(R)-1-(10,11-Dihydro-dibenzo[b,f]azepin-5-yl)-3-methylamino-propan-2-ol ((R)-OHDMI) and (S,S)-1-cyclopentyl-2-(5-fluoro-2-methoxy-phenyl)-1-morpholin-2-yl-ethanol (CFMME) were synthesized and found to be potent inhibitors of norepinephrine reuptake. Each was labelled efficiently in its methyl group with carbon-11 (t(1/2)=20.4 min) as a prospective radioligand for imaging brain norepinephrine transporters (NET) with positron emission tomography (PET). The uptake and distribution of radioactivity in brain following intravenous injection of each radioligand into cynomolgus monkey was examined in vivo with PET. After injection of (R)-[(11)C]OHDMI, the maximal whole brain uptake of radioactivity was very low (1.1% of injected dose; I.D.). For occipital cortex, thalamus, lower brainstem, mesencephalon and cerebellum, radioactivity ratios to striatum at 93 min after radioligand injection were 1.35, 1.35, 1.2, 1.2 and 1.0, respectively. After injection of [(11)C]CFMME, radioactivity readily entered brain (3.5% I.D.). Ratios of radioactivity to cerebellum at 93 min for thalamus, occipital cortex, region of locus coeruleus, mesencephalon and striatum were 1.35, 1.3, 1.3, 1.2 and 1.2, respectively. Radioactive metabolites in plasma were measured by radio-HPLC. (R)-[(11)C]OHDMI represented 75% of plasma radioactivity at 4 min after injection and 6% at 30 min. After injection of [(11)C]CFMME, 84% of the radioactivity in plasma represented parent at 4 min and 20% at 30 min. Since the two new hydroxylated radioligands provide only modest regional differentiation in brain uptake and form potentially troublesome lipophilic radioactive metabolites, they are concluded to be inferior to existing radioligands, such as (S,S)-[(11)C]MeNER, (S,S)-[(18)F]FMeNER-D(2) and (S,S)-[(18)F]FRB-D(4), for the study of brain NETs with PET in vivo.


Subject(s)
Azepines/chemical synthesis , Ethanol/analogs & derivatives , Morpholines/chemical synthesis , Norepinephrine Plasma Membrane Transport Proteins/metabolism , Propanols/chemical synthesis , Radiopharmaceuticals/chemical synthesis , Animals , Brain/diagnostic imaging , Brain/metabolism , Carbon Radioisotopes , Chromatography, High Pressure Liquid , Ethanol/chemical synthesis , Indicators and Reagents , Macaca fascicularis , Neostriatum/diagnostic imaging , Neostriatum/metabolism , Positron-Emission Tomography , Thalamus/diagnostic imaging , Thalamus/metabolism
7.
Bioorg Med Chem Lett ; 16(7): 2022-5, 2006 Apr 01.
Article in English | MEDLINE | ID: mdl-16413778

ABSTRACT

A novel series of tertiary alcohol containing 2-substituted benzyl morpholines have been discovered as potent and selective inhibitors of the norepinephrine transporter. Efficient synthetic routes were developed featuring a highly diastereoselective nucleophilic addition of benzyl Grignard reagents to enantiopure (4-benzylmorpholin-2-yl)phenylmethanone (11) as the key synthetic step. In vitro binding affinity for the norepinephrine, dopamine and serotonin transporters and in vivo examination of a select compound (16) in a pharmacodynamic animal model for norepinephrine reuptake inhibition are presented.


Subject(s)
Alcohols/chemistry , Morpholines/pharmacology , Norepinephrine Plasma Membrane Transport Proteins/antagonists & inhibitors , Crystallography, X-Ray , Dopamine Plasma Membrane Transport Proteins/antagonists & inhibitors , Morpholines/chemistry
8.
Bioorg Med Chem Lett ; 15(3): 699-703, 2005 Feb 01.
Article in English | MEDLINE | ID: mdl-15664840

ABSTRACT

Novel arylthiomethyl morpholines are potent selective norepinephrine reuptake inhibitors (NERIs) and dual serotonin/norepinephrine reuptake inhibitors (SRI/NERIs). The target compounds were prepared using a stereochemically versatile synthesis featuring an aldol condensation as the key step. One enantiomer of the 2-methoxy-substituted analogue was found to be a potent and selective norepinephrine reuptake inhibitor, whereas the opposite enantiomer was a potent dual serotonin/norepinephrine reuptake inhibitor.


Subject(s)
Adrenergic Uptake Inhibitors/chemical synthesis , Morpholines/chemical synthesis , Norepinephrine/antagonists & inhibitors , Selective Serotonin Reuptake Inhibitors/chemical synthesis , Adrenergic Uptake Inhibitors/pharmacology , Biogenic Amines/antagonists & inhibitors , Biogenic Amines/metabolism , Humans , Morpholines/pharmacology , Selective Serotonin Reuptake Inhibitors/pharmacology , Stereoisomerism , Structure-Activity Relationship
9.
Org Biomol Chem ; 2(5): 701-8, 2004 Mar 07.
Article in English | MEDLINE | ID: mdl-14985810

ABSTRACT

Two routes to the protected 4-hydroxymethyl-3-methylindole-2-carboxylate fragment 17 of the thiopeptide antibiotic nosiheptide are described starting from methyl 4-methylindole-2-carboxylate 11, itself prepared in two steps, or from 3-amino-4-chlorobenzoic acid 26. The first route can be adapted to the synthesis of a fragment of the related antibiotic glycothiohexide-alpha, the 3,4-bis(hydroxymethyl)indole-2-carboxylate in which the two hydroxymethyl groups are differentiated as in indole 19 or the lactone 20.


Subject(s)
Doxorubicin/analogs & derivatives , Indoles/chemical synthesis , Peptides/chemistry , Thiazoles/chemistry , Doxorubicin/chemistry , Indoles/chemistry , Lactones/chemical synthesis , Molecular Structure , Peptides/chemical synthesis , Thiazoles/chemical synthesis
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