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The path of tokamak fusion and International thermonuclear experimental reactor (ITER) is maintaining high-performance plasma to produce sufficient fusion power. This effort is hindered by the transient energy burst arising from the instabilities at the boundary of plasmas. Conventional 3D magnetic perturbations used to suppress these instabilities often degrade fusion performance and increase the risk of other instabilities. This study presents an innovative 3D field optimization approach that leverages machine learning and real-time adaptability to overcome these challenges. Implemented in the DIII-D and KSTAR tokamaks, this method has consistently achieved reactor-relevant core confinement and the highest fusion performance without triggering damaging bursts. This is enabled by advances in the physics understanding of self-organized transport in the plasma edge and machine learning techniques to optimize the 3D field spectrum. The success of automated, real-time adaptive control of such complex systems paves the way for maximizing fusion efficiency in ITER and beyond while minimizing damage to device components.
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BACKGROUND: Understanding stakeholders' perception of cure in prostate cancer (PC) is essential to preparing for effective communication about emerging treatments with curative intent. This study used artificial intelligence (AI) for landscape review and linguistic analysis of definition, context and value of cure among stakeholders in PC. MATERIALS AND METHODS: Subject-matter experts (SMEs) selected cure-related key words using Elicit, a semantic literature search engine, and extracted hits containing the key words from Medline, Sermo and Overton, representing academic researchers, health care providers (HCPs) and policymakers, respectively. NetBase Quid, a social media analytics and natural language processing tool, was used to carry out key word searches in social media (representing the general public). NetBase Quid analysed linguistics of key word-specific hit sets for key word count, geolocation and sentiments. SMEs qualitatively summarised key word-specific insights. Contextual terms frequently occurring with key words were identified and quantified. RESULTS: SMEs identified seven key words applicable to PC (number of acquired hits) across four platforms: Cure (12429), Survivor (6063), Remission (1904), Survivorship (1179), Curative intent (432), No evidence of disease (381) and Complete remission (83). Most commonly used key words were Cure by the general public and HCPs (11815 and 224 hits), Survivorship by academic researchers and Survivor by policymakers (378 hits each). All stakeholders discussed Cure and cure-related key words primarily in early-stage PC and associated them with positive sentiments. All stakeholders defined cure differently but communicated about it in relation to disease measurements (e.g. prostate-specific antigen) or surgery. Stakeholders preferred different terms when discussing cure in PC: Cure (academic researchers), Cure rates (HCPs), Potential cure and Survivor/Survivorship (policymakers) and Cure and Survivor (general public). CONCLUSION: This human-led, AI-assisted large-scale qualitative language-based research revealed that cure was commonly discussed by academic researchers, HCPs, policymakers and the general public, especially in early-stage PC. Stakeholders defined and contextualised cure in their communications differently and associated it with positive value.
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Inteligência Artificial , Neoplasias da Próstata , Mídias Sociais , Humanos , Masculino , Neoplasias da Próstata/terapia , Linguística/métodos , Política de Saúde , Percepção , Processamento de Linguagem NaturalRESUMO
BACKGROUND: In Taiwan, sequence type (ST) 239 and ST59 were two major clones among meticillin-resistant Staphylococcus aureus (MRSA) clinical isolates in the past two decades. USA300 (ST8) prevailed in the Americas but not in outside areas. Recently USA300 (ST8) emerged and was increasingly identified in Taiwan; we thus conducted an island-wide study to explore the role of USA300 among MRSA isolates. METHODS: One hundred MRSA bloodstream isolates identified in 2020 from each of the six participating hospitals in Taiwan were collected and characterized. The first 10 ST8 isolates from each hospital were further analysed by whole-genome sequencing. RESULTS: Of the 590 confirmed MRSA isolates, a total of 22 pulsotypes and 21 STs were identified. The strain of pulsotype AI/ST8 was the most common lineage identified, accounting for 187 isolates (31.7%) and dominating in five of six hospitals, followed by pulsotype A/ST239 (14.7%), pulsotype C/ST59 (13.9%) and pulsotype D/ST59 (9.2%). Of the 187 pulsotype AI/ST8 isolates, 184 isolates were characterized as USA300 and clustered in three major sub-pulsotypes, accounting for 78%. Ninety per cent of the 60 ST8 isolates for whole-genome sequencing were clustered in three major clades. CONCLUSIONS: In 2020, USA300 became the most common clone of MRSA in Taiwan, accounting for >30% of MRSA bloodstream isolates island wide. Most of USA300 isolates circulating in Taiwan might have been imported on multiple occasions and evolved into at least three successful local clades. MRSA USA300 has successfully established its role in Taiwan, an area outside of the Americas.
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Genótipo , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Sequenciamento Completo do Genoma , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Taiwan/epidemiologia , Humanos , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Epidemiologia Molecular , Hospitais/estatística & dados numéricos , Bacteriemia/microbiologia , Bacteriemia/epidemiologia , Tipagem MolecularRESUMO
AIM: To compare the diagnostic test of integrated 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography/computed tomography (FDG PET/CT) with that of magnetic resonance imaging (MRI) for the differentiation of malignant peripheral nerve sheath tumours (MPNSTs) in neurofibromatosis type 1 (NF1) patients. MATERIALS AND METHODS: A systematic search was performed in PubMed and EMBASE (last updated in 30 November 2022). Studies investigating the performance of FDG PET/CT and MRI for differentiation of MPNSTs were eligible for inclusion. Only studies reporting a direct comparison between these imaging methods were considered to establish precise summary estimates in the same setting of patients. RESULTS: The pooled estimate of sensitivity of FDG PET/CT was 0.99 and a pooled specificity of 0.53. The pooled estimate of sensitivity of MRI was 0.85 and a pooled specificity of 0.85. CONCLUSION: Analysis of the available studies indicated that FDG PET/CT and MRI had similar diagnostic performances for differentiation of MPNSTs in patients with NF1; however, either technique can be a complement to the other rather than being used singly.
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Neurofibromatose 1 , Neurofibrossarcoma , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neurofibromatose 1/diagnóstico por imagem , Neurofibromatose 1/patologia , Fluordesoxiglucose F18 , Glucose , Tomografia Computadorizada por Raios X/métodos , Sensibilidade e Especificidade , Tomografia por Emissão de Pósitrons/métodos , Imageamento por Ressonância Magnética/métodos , Compostos RadiofarmacêuticosRESUMO
Nuclear fusion is one of the most attractive alternatives to carbon-dependent energy sources1. Harnessing energy from nuclear fusion in a large reactor scale, however, still presents many scientific challenges despite the many years of research and steady advances in magnetic confinement approaches. State-of-the-art magnetic fusion devices cannot yet achieve a sustainable fusion performance, which requires a high temperature above 100 million kelvin and sufficient control of instabilities to ensure steady-state operation on the order of tens of seconds2,3. Here we report experiments at the Korea Superconducting Tokamak Advanced Research4 device producing a plasma fusion regime that satisfies most of the above requirements: thanks to abundant fast ions stabilizing the core plasma turbulence, we generate plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. A low plasma density combined with a moderate input power for operation is key to establishing this regime by preserving a high fraction of fast ions. This regime is rarely subject to disruption and can be sustained reliably even without a sophisticated control, and thus represents a promising path towards commercial fusion reactors.
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A fast-ion Dα (FIDA) diagnostics system was installed for core and edge measurements on KSTAR. This system has two tangential FIDA arrays that cover both blue- and redshifted Dα lines (cold: 656.09 nm) in active views along the neutral beam 1 A centerline. The spectral band is 647-662.5 nm, and it covers the Doppler shift of the emission from the maximum energy of the neutral beam (100 keV). A curved filter strip with a motorized stage adequately prevents saturation of the electron multiplying charge-coupled device signal by the cold Dα line from the plasma edge. From comparisons of the measured spectra and FIDASIM modeling code, the FIDA spectra are well matched quantitatively. Moreover, the first measurements show that the FIDA radiance agrees with the neutron rate in the time trace during external heating and perturbation. In addition, responses are observed in the core FIDA radiance during the edge-localized mode cycle.
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Predictive 3D optimization reveals a novel approach to modify a nonaxisymmetric magnetic perturbation to be entirely harmless for tokamaks, by essentially restoring quasisymmetry in perturbed particle orbits as much as possible. Such a quasisymmetric magnetic perturbation (QSMP) has been designed and successfully tested in the KSTAR and DIII-D tokamaks, demonstrating no performance degradation despite the large overall amplitudes of nonaxisymmetric fields and strong response otherwise expected in the tested plasmas. The results indicate that a quasisymmetric optimization is a robust path of error field correction across the resonant and nonresonant field spectrum in a tokamak, leveraging the prevailing concept of quasisymmetry for general 3D plasma confinement systems such as stellarators. The optimization becomes, in fact, a simple eigenvalue problem to the so-called torque response matrices if a perturbed equilibrium is calculated consistent with nonaxisymmetric neoclassical transport.
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AIMS: To study the association between number and positions of mutations with MICs of fluoroquinolone non-susceptible Haemophilus influenzae. METHODS AND RESULTS: More than 40% of 48 H. influenzae isolated from nursing home residents were not susceptible to fluoroquinolone. Amino acid changes in the quinolone resistance determining regions, and correlation with MICs and inhibition zone diameters were analysed. All isolates with reduced susceptibility to fluoroquinolones (MIC ≥0·125 µg ml-1 ) had at least one mutation in gyrA at position 84 and were resistant to nalidixic acid. Compared to isolates with reduced susceptibility, resistant isolates were associated with mutations in gyrA at positions 88 and 134, and in parC at position 88 (P < 0·001). Inhibition zone diameter for nalidixic acid disk ≥23 mm may detect susceptible isolates. CONCLUSIONS: Reduced susceptibility to fluoroquinolones was associated with mutations at position 84 in gyrA. A further increase in fluoroquinolone MIC was associated with mutations in gyrA at positions 88 and 134, and parC at position 88. SIGNIFICANCE AND IMPACT OF THE STUDY: Due to limited resistant H. influenzae strains, prior studies on association between positions of mutations and fluoroquinolone MICs were inconclusive. The comparison of mutations between isolates with susceptibility, reduced susceptibility and high resistance supported the importance of the present study.
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Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/farmacologia , Haemophilus influenzae/efeitos dos fármacos , DNA Girase/genética , DNA Topoisomerase IV/genética , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/genética , Haemophilus influenzae/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Mutação , Casas de Saúde , TaiwanRESUMO
BACKGROUND: Postgraduate vocational training in family medicine (FM) is essential for physicians to build capacity and develop quality primary care. Inadequate standards in training and curriculum development can contribute to poor recruitment and retention of doctors in primary care. This study aimed to investigate: 1) the satisfaction level of doctors regarding vocational training in family medicine and associated demographics; and 2) the satisfaction level of doctors regarding their family medicine career and associated factors. METHOD: This is a cross sectional study of all family medicine physicians across all government-funded primary care clinics (GOPCs). The study questionnaire consisted of items from a standardized and validated physician survey named the Physician Worklife Survey (PWS) (Konrad et al., Med Care, 1999). We selected three scales (7 items) relating to global job satisfaction, global career satisfaction and global specialty (family medicine) satisfaction with additional items on training and demographics. All significant variables in bivariate analyses were further examined using stepwise logistic regression. RESULTS: Out of 424 eligible family medicine physicians, 368 physicians successfully completed the questionnaire. The response rate was 86.8%. Most participants were male (52.6%), were aged between 35 and 44 years (55.5%), were FM specialists (42.4%), graduated locally (86.2%), and had postgraduate qualifications. Eighty-two percent (82%) of participants were satisfied with their training. Having autonomy and protected time for training were associated with satisfaction with FM training. Satisfaction with family medicine as a career was correlated with physicians' satisfaction with their current job. Doctors who did not enroll in training (p < 0.001) and physicians who were older (p = 0.023) were significantly less satisfied. Stepwise multivariate regression showed that doctors who subjectively believed their training as "broad and in depth' had higher career satisfaction (p < 0.001). CONCLUSION: Overall, the satisfaction level of physicians on current family medicine training in Hong Kong was high. Having autonomy and protected time for training is associated with higher training satisfaction levels. Perceiving FM training as "broad and in-depth" is associated with higher family medicine career satisfaction.
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Medicina de Família e Comunidade/educação , Satisfação no Emprego , Educação Vocacional , Adulto , Estudos Transversais , Feminino , Clínicos Gerais/educação , Clínicos Gerais/psicologia , Clínicos Gerais/estatística & dados numéricos , Hong Kong , Humanos , Masculino , Inquéritos e QuestionáriosRESUMO
A small nonaxisymmetric (3D) magnetic field can induce nonambipolar transport of the particle species confined in a tokamak and thus a significant change of plasma rotation. This process can be in a favor of instability control in the region where the tokamak plasma is sufficiently collisional and resistive, as observed in the applications of n=1 resonant magnetic perturbations to the KSTAR tokamak. The plasma rotation can be globally accelerated due to radially drifting electrons and constrained to the electron root, if the radial transport is enhanced by an amplified 3D response. This mechanism is verified by a kinetically self-consistent magnetohydrodynamic modeling for both response and transport, which offers the quantitative explanations on the internal n=1 structure detected by electron-cyclotron-emission imaging and the cocurrent plasma spinning observed in the experiments.
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The propagation dynamics of resonant magnetic perturbation fields in KSTAR H-mode plasmas with injection of small edge perturbations produced by a supersonic molecular beam injection is reported for the first time. The results show that the perturbation field first excites a plasma response on the q=3 magnetic surface and then propagates inward to the q=2 surface with a radially averaged propagation velocity of resonant magnetic perturbations field equal to 32.5 m/ s. As a result, the perturbation field brakes the toroidal rotation on the q=3 surface first causing a momentum transport perturbation that propagates both inward and outward. A higher density fluctuation level is observed. The propagation velocity of the resonant magnetic perturbations field is larger than the radial propagation velocity of the perturbation in the toroidal rotation.
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Planarians have a long history in the fields of developmental and regenerative biology. These animals have also sparked interest in neuroscience due to their neuroanatomy, spectrum of simple behaviors, and especially, their almost unparalleled ability to generate new neurons after any type of injury. Research in adult planarians has revealed that neuronal subtypes homologous to those found in vertebrates are generated from stem cells throughout their lives. This feat is recapitulated after head amputation, wherein animals are capable of regenerating whole brains and regaining complete neural function. In this review, we summarize early studies on the anatomy and function of the planarian nervous system and discuss our present knowledge of the molecular mechanisms governing neurogenesis in planarians. Modern studies demonstrate that the transcriptional programs underlying neuronal specification are conserved in these remarkable organisms. Thus, planarians are outstanding models to investigate questions about how stem cells can replace neurons in vivo. WIREs Dev Biol 2017, 6:e266. doi: 10.1002/wdev.266 For further resources related to this article, please visit the WIREs website.
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Sistema Nervoso/citologia , Células-Tronco Neurais/citologia , Neurogênese/fisiologia , Neurônios/citologia , Planárias/crescimento & desenvolvimento , Animais , Água DoceRESUMO
Solitary perturbations (SPs) localized both poloidally and radially are detected within ~100 µs before the partial collapse of the high pressure gradient boundary region (called pedestal) of magnetized toroidal plasma in the KSTAR tokamak device. The SP develops with a low toroidal mode number (typically unity) in the pedestal ingrained with quasi-stable edge-localized mode (QSM) which commonly appears during the inter-collapse period. The SPs have smaller mode pitch and different (often opposite) rotation velocity compared to the QSMs. Similar solitary perturbations are also frequently observed before the onset of complete pedestal collapse, suggesting a strong connection between the SP generation and the pedestal collapse.
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The asexual freshwater planarian is a constitutive adult, whose central nervous system (CNS) is in a state of constant homeostatic neurogenesis. However, very little is known about the extrinsic signals that act on planarian stem cells to modulate rates of neurogenesis. We have identified two planarian homeobox transcription factors, Smed-nkx2.1 and Smed-arx, which are required for the maintenance of cholinergic, GABAergic, and octopaminergic neurons in the planarian CNS. These very same neurons also produce the planarian hedgehog ligand (Smed-hh), which appears to communicate with brain-adjacent stem cells to promote normal levels of neurogenesis. Planarian stem cells nearby the brain express core hh signal transduction genes, and consistent hh signaling levels are required to maintain normal production of neural progenitor cells and new mature cholinergic neurons, revealing an important mitogenic role for the planarian hh signaling molecule in the adult CNS.
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Encéfalo/fisiologia , Proteínas Hedgehog/metabolismo , Neurogênese , Neurônios/fisiologia , Platelmintos/fisiologia , Animais , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Reversible phosphorylation is a fundamental regulatory mechanism, intricately coordinated by kinases and phosphatases, two classes of enzymes widely disrupted in human disease. To better understand the functions of the relatively understudied phosphatases, we have used complementary affinity purification and proximity-based interaction proteomics approaches to generate a physical interactome for 140 human proteins harboring phosphatase catalytic domains. We identified 1,335 high-confidence interactions (1,104 previously unreported), implicating these phosphatases in the regulation of a variety of cellular processes. Systematic phenotypic profiling of phosphatase catalytic and regulatory subunits revealed that phosphatases from every evolutionary family impinge on mitosis. Using clues from the interactome, we have uncovered unsuspected roles for DUSP19 in mitotic exit, CDC14A in regulating microtubule integrity, PTPRF in mitotic retraction fiber integrity, and DUSP23 in centriole duplication. The functional phosphatase interactome further provides a rich resource for ascribing functions for this important class of enzymes.
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Mitose , Monoéster Fosfórico Hidrolases/metabolismo , Mapas de Interação de Proteínas , Evolução Biológica , Centríolos/metabolismo , Fosfatases de Especificidade Dupla/metabolismo , Células HeLa , Humanos , Fenótipo , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Subunidades Proteicas/metabolismo , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/metabolismo , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Freshwater planarians are well known for their regenerative abilities. Less well known is how planarians maintain spatial patterning in long-lived adult animals or how they re-pattern tissues during regeneration. HOX genes are good candidates to regulate planarian spatial patterning, yet the full complement or genomic clustering of planarian HOX genes has not yet been described, primarily because only a few have been detectable by in situ hybridization, and none have given morphological phenotypes when knocked down by RNAi. RESULTS: Because the planarian Schmidtea mediterranea (S. mediterranea) is unsegmented, appendage less, and morphologically simple, it has been proposed that it may have a simplified HOX gene complement. Here, we argue against this hypothesis and show that S. mediterranea has a total of 13 HOX genes, which represent homologs to all major axial categories, and can be detected by whole-mount in situ hybridization using a highly sensitive method. In addition, we show that planarian HOX genes do not cluster in the genome, yet 5/13 have retained aspects of axially restricted expression. Finally, we confirm HOX gene axial expression by RNA deep-sequencing 6 anterior-posterior "zones" of the animal, which we provide as a dataset to the community to discover other axially restricted transcripts. CONCLUSIONS: Freshwater planarians have an unappreciated HOX gene complexity, with all major axial categories represented. However, we conclude based on adult expression patterns that planarians have a derived body plan and their asexual lifestyle may have allowed for large changes in HOX expression from the last common ancestor between arthropods, flatworms, and vertebrates. Using our in situ method and axial zone RNAseq data, it should be possible to further understand the pathways that pattern the anterior-posterior axis of adult planarians.
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In this study, we compared the efficiency of simple sequence repeat (SSR) and sequence specific amplified polymorphism (SSAP) markers for analyzing genetic diversity, genetic relationships, and population structure of 87 super sweet corn inbred lines from different origins. SSR markers showed higher average gene diversity and Shannon's information index than SSAP markers. To assess genetic relationships and characterize inbred lines using SSR and SSAP markers, genetic similarity (GS) matrices were constructed. The dendrogram using SSR marker data showed a complex pattern with nine clusters and a GS of 53.0%. For SSAP markers, three clusters were observed with a GS of 50.8%. Results of combined marker data showed six clusters with 53.5% GS. To analyze the genetic population structure of SSR and SSAP marker data, the 87 inbred lines were divided into groups I, II, and admixed based on the membership probability threshold of 0.8. Using combined marker data, the population structure was K = 3 and was divided into groups I, II, III, and admixed. This study represents a comparative analysis of SSR and SSAP marker data for the study of genetic diversity and genetic relationships in super sweet corn inbred lines. Our results would be useful for maize-breeding programs in Korea.
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Variação Genética , Genética Populacional , Repetições de Microssatélites , Zea mays/genética , Melhoramento Vegetal , República da CoreiaRESUMO
Neoblasts are adult stem cells (ASCs) in planarians that sustain cell replacement during homeostasis and regeneration of any missing tissue. While numerous studies have examined genes underlying neoblast pluripotency, molecular pathways driving postmitotic fates remain poorly defined. In this study, we used transcriptional profiling of irradiation-sensitive and irradiation-insensitive cell populations and RNA interference (RNAi) functional screening to uncover markers and regulators of postmitotic progeny. We identified 32 new markers distinguishing two main epithelial progenitor populations and a planarian homolog to the MEX3 RNA-binding protein (Smed-mex3-1) as a key regulator of lineage progression. mex3-1 was required for generating differentiated cells of multiple lineages, while restricting the size of the stem cell compartment. We also demonstrated the utility of using mex3-1(RNAi) animals to identify additional progenitor markers. These results identified mex3-1 as a cell fate regulator, broadly required for differentiation, and suggest that mex3-1 helps to mediate the balance between ASC self-renewal and commitment.
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Diferenciação Celular , Proteínas de Ligação a RNA/metabolismo , Células-Tronco/fisiologia , Animais , Células Epiteliais/fisiologia , Perfilação da Expressão Gênica , Testes Genéticos , Planárias , Interferência de RNA , Transcrição GênicaRESUMO
Gastrin is the main hormone stimulating gastric acid secretion, but it exerts proliferative and anti-apoptotic actions on various cancer cell types, in addition to its well-known trophic effect on enterochromaffin-like cells. As treatment with proton pump inhibitors (PPIs) increases the biosynthesis and secretion of gastrin, it has been postulated that treatment with PPIs could increase the risk of cancer, especially in Barrett's esophagus, gastric carcinoids, and colorectal cancer (CRC). Some tumors produce gastrin of their own, which can act in an autocrine manner to promote tumor growth. In addition, gastrin is known to foster the tumor microenvironment. However, in spite of these potentially increased cancer risks due to PPI-induced hypergastrinemia, prospective, large-scale cohort studies did not show an increase in CRC prevalence. The question as to why the long-term use of PPIs was not associated with an increased cancer risk of CRC might be answered by the fact that the PPIs antagonized the trophic effects of hypergastrinemia. Furthermore, the blockade of proton pumps or potassium channels in cancer cells could limit the abnormal glycolytic energy metabolism of cancer cells. Apart from their suppressive effect on gastric acids, PPIs exert an anti-tumor effect through the selective induction of apoptosis as well as an anti-inflammatory effect, and they protect cells from developing chemo- or radiotherapeutic resistance. Moreover, the anti-carcinogenic actions of PPIs were augmented with PPI-induced hypergastrinemia. Together with their potential targeted killing of cancer stem cells, these effects demonstrate their potential anti-cancer actions.
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Carcinogênese/efeitos dos fármacos , Gastrinas/antagonistas & inibidores , Inibidores da Bomba de Prótons/farmacologia , Inibidores da Bomba de Prótons/uso terapêutico , Bombas de Próton/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinogênese/metabolismo , Gastrinas/metabolismo , Humanos , Neoplasias Gástricas/metabolismoRESUMO
Serotonin transporter blockade with selective serotonin reuptake inhibitors (SSRIs) was recently shown to counteract L-DOPA-induced dyskinesia in 6-hydroxydopamine (6-OHDA)-lesioned rats. However, this effect has never been described in Parkinson's disease (PD) patients, despite that they often receive SSRIs for the treatment of depression. In the present study, we investigated the efficacy of the SSRI citalopram against dyskinesia in two experimental models of PD, the 6-OHDA-lesioned rat and 1-methyl-4-phenyl 1,2,3,6-tetrahydropyridine (MPTP)-treated macaque. First, we studied the acute and chronic effect of citalopram, given at different time points before L-DOPA, in L-DOPA-primed parkinsonian rats. Moreover, the acute effect of citalopram was also evaluated in dyskinetic MPTP-treated macaques. In L-DOPA-primed rats, a significant and long-lasting reduction of L-DOPA-induced dyskinesia (LID) was observed only when citalopram was given 30 min before L-DOPA, suggesting that the time of injection relative to L-DOPA is a key factor for the efficacy of the treatment. Interestingly, an acute challenge with the 5-HT1A/1B receptor agonist eltoprazine, given at the end of the chronic study, was equally effective in reducing LID in rats previously chronically treated with L-DOPA or L-DOPA plus citalopram, suggesting that no auto-receptor desensitization was induced by chronic citalopram treatment. In MPTP-treated macaques, citalopram produced a striking suppression of LID but at the expense of L-DOPA therapeutic efficacy, which represents a concern for possible clinical application.