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1.
J Health Organ Manag ; ahead-of-print(ahead-of-print)2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38839779

ABSTRACT

PURPOSE: The purpose of this paper is to highlight the joint impact of competitive culture and knowledge behaviors (sharing, hoarding and hiding) on workplace happiness among healthcare professionals. It addresses a literature gap that critiques the development of happiness programs in healthcare that overlook organizational, social and economic dynamics. The study is based on the Social Exchange Theory, the Conservation of Resources Theory and the principles of Positive Psychology. DESIGN/METHODOLOGY/APPROACH: The study analyzes a linear relationship between variables using a structural equation model and a partial least squares approach. The data are sourced from a survey of 253 healthcare professionals from Portuguese healthcare organizations. FINDINGS: The data obtained from the model illustrate a positive correlation between competitive culture and knowledge hoarding as well as knowledge hiding. Interestingly, a competitive culture also fosters workplace happiness among healthcare professionals. The complex relationship between knowledge behaviors becomes evident since both knowledge hoarding and sharing positively affected these professionals' workplace happiness. However, no direct impact was found between knowledge hiding and workplace happiness, suggesting that it negatively mediates other variables. ORIGINALITY/VALUE: This research addresses a previously identified threefold gap. First, it delves into the pressing need to comprehend behaviors that enhance healthcare professionals' workplace satisfaction. Second, it advances studies by empirically examining the varied impacts of knowledge hiding, hoarding and sharing. Finally, it sheds light on the repercussions of knowledge behaviors within an under-explored context - healthcare organizations.


Subject(s)
Happiness , Health Personnel , Workplace , Humans , Health Personnel/psychology , Workplace/psychology , Adult , Male , Female , Portugal , Surveys and Questionnaires , Middle Aged , Organizational Culture , Job Satisfaction
2.
Polymers (Basel) ; 15(3)2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36771914

ABSTRACT

The growing quantities of plastic waste have raised environmental concerns, with almost a quarter of disposed plastics being sent to landfill. This has motivated research efforts into various recycling technologies to ease dependence on fossil resources, increasing circularity. Irradiation of various kinds, such as electron beam, beta and gamma rays, has been studied in the past as a way of revamping end-of-life polymer properties. The present work focuses on the effects of gamma radiation on the processability of new and recycled polymers, which is intimately linked with their rheological properties. In this study, both virgin and recycled polymers were irradiated under different radiation doses and the effects of the radiation on their viscosity assessed and compared. Results were analyzed making use of different theoretical relationships, and the causes of the changes in rheology were investigated by means of various characterization techniques, such as GPC, FTIR, EPR and DSC. Finally, the rheological curves of all samples were fitted to the Ostwald-de Waele relationship and the dependence of its parameters on the absorbed dose fitted to a function.

3.
Int J Mol Sci ; 22(18)2021 Sep 14.
Article in English | MEDLINE | ID: mdl-34576100

ABSTRACT

Approximately 25% of colorectal cancer (CRC) patients develop peritoneal metastasis, a condition associated with a bleak prognosis. The CRC peritoneal dissemination cascade involves the shedding of cancer cells from the primary tumor, their transport through the peritoneal cavity, their adhesion to the peritoneal mesothelial cells (PMCs) that line all peritoneal organs, and invasion of cancer cells through this mesothelial cell barrier and underlying stroma to establish new metastatic foci. Exosomes produced by cancer cells have been shown to influence many processes related to cancer progression and metastasis. In epithelial ovarian cancer these extracellular vesicles (EVs) have been shown to favor different steps of the peritoneal dissemination cascade by changing the functional phenotype of cancer cells and PMCs. Little is currently known, however, about the roles played by exosomes in the pathogenesis and peritoneal metastasis cascade of CRC and especially about the molecules that mediate their interaction and uptake by target PMCs and tumor cells. We isolated exosomes by size-exclusion chromatography from CRC cells and performed cell-adhesion assays to immobilized exosomes in the presence of blocking antibodies against surface proteins and measured the uptake of fluorescently-labelled exosomes. We report here that the interaction between integrin α5ß1 on CRC cells (and PMCs) and its ligand ADAM17 on exosomes mediated the binding and uptake of CRC-derived exosomes. Furthermore, this process was negatively regulated by the expression of tetraspanin CD9 on exosomes.


Subject(s)
ADAM17 Protein/metabolism , Colorectal Neoplasms/metabolism , Exosomes/metabolism , Integrin alpha5beta1/metabolism , Adenocarcinoma/metabolism , Cell Adhesion , Cell Line, Tumor , Epithelium/pathology , Exosomes/ultrastructure , Fibronectins/metabolism , Humans , Peritoneum/pathology , Tetraspanin 29/metabolism
4.
Article in English | MEDLINE | ID: mdl-32354118

ABSTRACT

This study examines the effects that ambidextrous relationships, i.e., oriented relationships within a firm towards the development of exploitation activities and oriented relationships towards the development of exploration activities, have on employee performance in terms of creativity, research and development (R&D), and sustainable innovation performance. We contend that informal relationships affect employee creativity and R&D. However, formal relationships affect employee creativity and sustainable innovation performance. The purpose of this study is to inject new positive relationships into firms by examining ambidextrous relationships and the moderating role of social capability in the relationships-innovation effect. We empirically tested our hypotheses by using multisource data collected from 245 Spanish firms across 14 industries. Our structural equation models suggest that these two types of relationship predict employee creativity, which in turn increases sustainable innovation performance and R&D. The results reveal that the effects between informal relationships and creativity are stronger, as are the effects between formal relationships and sustainable innovation performance. A multigroup structural analysis also reveals that effects between informal and formal relationships, employee creativity, R&D, and sustainable innovation performance are stronger within firms that have employees with high social capability. The efforts and investments made in employee social capital support the development of new ideas, R&D, and innovation success. Support is provided for an ambidextrous Human Resource Management (HRM) approach which is relevant for innovation, and several practical recommendations and implementation guidelines for Small and Medium Enterprises (SMEs) are provided. This study provides a plausible explanation of two important management mechanisms for enhancing creativity-R&D and sustainable innovation performance. Relationships are malleable, and this study suggests that fostering formal and informal relationships might hold the key to sustainable innovation performance and unlocking desirable employee behavior.


Subject(s)
Creativity , Research , Social Capital , Humans , Investments
5.
Pflugers Arch ; 468(10): 1779-92, 2016 10.
Article in English | MEDLINE | ID: mdl-27558258

ABSTRACT

It is known that the sustained depolarisation of adrenal medullary bovine chromaffin cells (BCCs) with high K(+) concentrations produces an initial sharp catecholamine release that subsequently fades off in spite depolarisation persists. Here, we have recreated a sustained depolarisation condition of BCCs by treating them with the Na(+)/K(+) ATPase blocker ouabain; in doing so, we searched experimental conditions that permitted the development of a sustained long-term catecholamine release response that could be relevant during prolonged stress. BCCs were perifused with nominal 0Ca(2+) solution, and secretion responses were elicited by intermittent application of short 2Ca(2+) pulses (Krebs-HEPES containing 2 mM Ca(2+)). These pulses elicited a biphasic secretory pattern with an initial 30-min period with secretory responses of increasing amplitude and a second 30-min period with steady-state, non-inactivating responses. The initial phase was not due to gradual depolarisation neither to gradual increases of the cytosolic calcium transients ([Ca(2+)]c) elicited by 2Ca(2+) pulses in BBCs exposed to ouabain; both parameters increased soon after ouabain addition. Νifedipine blocked these responses, and FPL64176 potentiated them, suggesting that they were triggered by Ca(2+) entry through non-inactivating L-type calcium channels. This was corroborated by nifedipine-evoked blockade of the L-type Ca(2+) channel current and the [Ca(2+)]c transients elicited by 2Ca(2+) pulses. Furthermore, the plasmalemmal Na(+)/Ca(2+) exchanger (NCX) blocker SEA0400 caused a mild inhibition followed by a large rebound increase of the steady-state secretory responses. We conclude that these two phases of secretion are mostly contributed by Ca(2+) entry through L calcium channels, with a minor contribution of Ca(2+) entry through the reverse mode of the NCX.


Subject(s)
Calcium Channels, L-Type/metabolism , Calcium Signaling , Chromaffin Cells/metabolism , Enzyme Inhibitors/pharmacology , Ouabain/pharmacology , Aniline Compounds/pharmacology , Animals , Catecholamines/metabolism , Cattle , Cells, Cultured , Chromaffin Cells/drug effects , Phenyl Ethers/pharmacology
6.
J Mass Spectrom ; 51(8): 651-664, 2016 Aug.
Article in English | MEDLINE | ID: mdl-28239974

ABSTRACT

The primary functions of adrenal medullary chromaffin cells are the synthesis and storage in their chromaffin vesicles of the catecholamines noradrenaline (NA) and adrenaline (AD), and their subsequent release into the bloodstream by Ca2+ -dependent exocytosis under conditions of fear or stress (fight or flight response). Several monoamines, nucleotides and opiates, such as leucine-enkephalin (LENK) and methionine-enkephalin (MENK), are also co-stored and co-released with the catecholamines. However, other neurotransmitters have not been studied in depth. Here, we present a novel high-resolution liquid chromatography-tandem mass spectrometry approach for the simultaneous monitoring of 14 compounds stored and released in bovine chromaffin cells (BCCs). We validated the analytical method according to the recommendations of the EMA and FDA by testing matrix effect, selectivity, sensitivity, precision, accuracy, stability and carry-over. After testing on six batches of BCCs from different cultures, the method enabled simultaneous quantitative determination of monoamines (AD, NA, dopamine, serotonin, 5-hydroxyindoleacetic acid, histamine and metanephrine), amino acids (L-glutamic acid, γ-aminobutyric acid), nucleotides (adenosine 5'-diphosphate, adenosine 5'-monophosphate, cyclic adenosine 5'-monophosphate) and neuropeptides (LENK and MENK) in the intracellular content, basal secretion and acetylcholine induced secretion of BBCs. The high-resolution approach used here enabled us to determine the levels of 14 compounds in the same BCC batch in only 16 min. This novel approach will make it possible to study the regulatory mechanisms of Ca2+ signaling, exocytosis and endocytosis using different neurotrophic factors and/or secretagogues as stimuli in primary BCC cultures. Our method is actually being applied to human plasma samples of different therapeutic areas where sympathoadrenal axis is involved in stress situations such as Alzheimer's disease, migraine or cirrhosis, to improve diagnosis and clinical practice. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Amino Acids/analysis , Catecholamines/analysis , Chromaffin Cells/metabolism , Neuropeptides/analysis , Nucleotides/analysis , Amino Acids/chemistry , Animals , Calibration , Catecholamines/chemistry , Cattle , Chromatography, Liquid/methods , Limit of Detection , Linear Models , Neuropeptides/chemistry , Neurosecretion , Nucleotides/chemistry , Reproducibility of Results , Tandem Mass Spectrometry/methods
7.
J Neurochem ; 135(5): 880-96, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26365051

ABSTRACT

In search of druggable synthetic lipids that function as potential modulators of synaptic transmission and plasticity, we synthesized sulfoglycolipid IG20, which stimulates neuritic outgrowth. Here, we have explored its effects on ion channels and exocytosis in bovine chromaffin cells. IG20 augmented the rate of basal catecholamine release. Such effect did not depend on Ca(2+) mobilization from intracellular stores; rather, IG20-elicited secretion entirely dependent on Ca(2+) entry through L-subtype voltage-activated Ca(2+) channels. Those channels were recruited by cell depolarization mediated by IG20 likely through its ability to enhance the recruitment of Na(+) channels at more hyperpolarizing potentials. Confocal imaging with fluorescent derivative IG20-NBD revealed its rapid incorporation and confinement into the plasmalemma, supporting the idea that IG20 effects are exerted through a plasmalemmal-delimited mechanism. Thus, synthetic IG20 seems to mimic several physiological effects of endogenous lipids such as regulation of ion channels, Ca(2+) signaling, and exocytosis. Therefore, sulfoglycolipid IG20 may become a pharmacological tool for investigating the role of the lipid environment on neuronal excitability, ion channels, neurotransmitter release, synaptic efficacy, and neuronal plasticity. It may also inspire the synthesis of druggable sulfoglycolipids aimed at increasing synaptic plasticity and efficacy in neurodegenerative diseases and traumatic brain-spinal cord injury. The novel synthetic sulfoglycolipid IG20 mimics several physiological effects of endogenous lipids such as regulation of ion channels, Ca(2+) signaling, and exocytosis. This profile may eventually drive enhanced synaptic plasticity and efficacy.


Subject(s)
Chromaffin Cells/drug effects , Exocytosis/drug effects , Glycolipids/pharmacology , Sodium Channels/physiology , Animals , Azoles/metabolism , Azoles/pharmacology , Cadmium/pharmacology , Calcium/metabolism , Catecholamines/metabolism , Cattle , Cells, Cultured , Chromaffin Cells/physiology , Cytosol/drug effects , Cytosol/metabolism , Enzyme Inhibitors/pharmacology , Fura-2/analogs & derivatives , Fura-2/metabolism , Glycolipids/metabolism , Membrane Transport Modulators/pharmacology , Nifedipine/pharmacology , Nitrobenzenes/metabolism , Nitrobenzenes/pharmacology , Potassium/metabolism , Potassium/pharmacology , Sodium/metabolism , Tetrodotoxin/pharmacology , Thapsigargin/pharmacology
8.
Rev. cuba. enferm ; 8(2): 86-91, jul.-dic. 1992. tab
Article in Spanish | CUMED | ID: cum-1161

ABSTRACT

El entrenamiento físico sistemático influye sobre una serie de cambios en el organismo, no sólo mejora el funcionamiento del aparato cardiovascular, sino todo los órganos y sistemas, aumenta la capacidad funcional del individuo, disminuye la tensión por estrés y controla o normaliza las cifras de tensión arterial. Por lo antes expresado se decide hacer un estudio de 50 pacientes que son el 100 por ciento de los hipertensos incorporados a los ejercicios físicos, sin que tengan otra enfermedad asociada, con el objetivo de determinar la influencia de la actividad física sistemática en el tratamiento de la hipertensión arterial. En los resultados se demuestra que pacientes que anteriormente tenían las cifras tensionales elevadas y que no hacían ejercicios físicos, al incorporarse sistemáticamente a ellos, la mayoría se han controlado o han mejorado y han disminuido o eliminado la ingestión de medicamentos


Subject(s)
Humans , Male , Female , Hypertension/therapy , Hypertension/prevention & control , Physical Exertion
9.
Rev. cuba. enferm ; 8(2): 86-91, jul.-dic. 1992. tab
Article in Spanish | LILACS, BDENF - Nursing | ID: lil-132314

ABSTRACT

El entrenamiento físico sistemático influye sobre una serie de cambios en el organismo, no sólo mejora el funcionamiento del aparato cardiovascular, sino todo los órganos y sistemas, aumenta la capacidad funcional del individuo, disminuye la tensión por estrés y controla o normaliza las cifras de tensión arterial. Por lo antes expresado se decide hacer un estudio de 50 pacientes que son el 100 por ciento de los hipertensos incorporados a los ejercicios físicos, sin que tengan otra enfermedad asociada, con el objetivo de determinar la influencia de la actividad física sistemática en el tratamiento de la hipertensión arterial. En los resultados se demuestra que pacientes que anteriormente tenían las cifras tensionales elevadas y que no hacían ejercicios físicos, al incorporarse sistemáticamente a ellos, la mayoría se han controlado o han mejorado y han disminuido o eliminado la ingestión de medicamentos


Subject(s)
Humans , Male , Female , Exercise , Hypertension/prevention & control , Hypertension/therapy
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