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1.
Microb Pathog ; 142: 104036, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32017958

RESUMO

BACKGROUND: In the immunocompromised conditions following renal transplantation, BK virus can reactivate and cause BK virus associated nephropathy (BKVN). Increased BK viral loads and extended duration of infection have been linked to development of BKVN. The aim of this study was to observe the incidence of BKV infection and BKVN, and kinetics of infection and disease in renal transplantation recipients. METHODS: From 2014 to 2018, we conducted a longitudinal cohort observational study of 139 renal transplantation patients treated at a single clinic. Quantitative PCR assay was conducted to assess longitudinal BK viral loads. Analysis of patient clinical characteristics was performed to determine risk factors for BKV infection and associated disease. RESULTS: Of our cohort, 29 (20.9%) patients developed high BK viremia, and 7 (5.0%) developed biopsy-confirmed BKVN. Clinical parameters associated with diabetes (FBS, HbA1c) and hyperlipidemia (TG, TC, LDL-C) were found to be correlated with development of high BK viremia or BKVN. In 3 of 4 patients receiving intravenous immunoglobulin (IVIG) treatment, BK viral loads were reduced by at least 1 log within 2-3 months of administration. Significant differences were measured in BK viral loads and kidney function between BK viremic patients and BKVN patients by 3-9 months post-transplantation. CONCLUSIONS: We identified diabetes and hyperlipidemia as potential risk factors for development of high BK viremia and/or BKVN. IVIG was seen to be effective in reducing viral titers. The period 3-9 months post-transplantation was identified as important for development of BKVN from high BK viremia.

2.
J Card Surg ; 35(4): 860-867, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32058613

RESUMO

Coronary artery bypass graft (CABG) is one of the most commonly performed cardiac surgeries in the world. CABG using the internal mammary artery (IMA) remains the gold standard intervention for myocardial intervention in multivessel coronary artery disease. IMA harvesting can be performed with various techniques and approaches: pedicled vs skeletonized harvesting technique as well as approaches such as conventional sternotomy, robotic and endoscopic approaches. While each technique and approach have their respective advantages and disadvantages, evidence remains varied between cohorts. Traditionally, IMA has been used as an in situ conduit; however, IMA free grafts also provide satisfactory outcomes in certain situations. This literature review aims to explore the efficacy of different techniques and approaches of IMA harvesting and grafting. With evidence compiled, this will provide an overview of the complexity of CABG and locate gaps in current literature to direct future research.


Assuntos
Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/cirurgia , Artéria Torácica Interna/cirurgia , Revascularização Miocárdica/métodos , Coleta de Tecidos e Órgãos/métodos , Endoscopia/métodos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Esternotomia/métodos , Coleta de Tecidos e Órgãos/tendências , Transplantes
3.
Proteomics ; 19(8): e1800149, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30758141

RESUMO

Exosomes are a subset of extracellular vesicles released by all cell types and involved in local and systemic intercellular communication. In the past decade, research into exosomes has swelled as their important role in the mediation of health and disease has been increasingly established and acknowledged. Exosomes carry a diverse range of cargo including proteins, nucleic acids, and lipids derived from their parental cell that, when delivered to the recipient cell, can confer pathogenic or therapeutic effects through modulation of immunity and inflammation. In this review, the role of exosomes on mediation of immune and inflammatory responses, and their participation in diseases with a significant inflammatory component is discussed. The considerable potential for exosomes in therapy and diagnosis of inflammatory diseases is also highlighted.


Assuntos
Exossomos/metabolismo , Inflamação/metabolismo , Aminoácidos/metabolismo , Animais , Proliferação de Células/fisiologia , Fibroblastos/metabolismo , Glicogênio/metabolismo , Humanos , Inflamação/imunologia , Ácido Láctico/metabolismo
4.
Am J Epidemiol ; 188(8): 1529-1538, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31062837

RESUMO

National data on dengue notifications do not capture all dengue infections and do not reflect the true intensity of disease transmission. To assess the true dengue infection rate and disease control efforts in Singapore, we conducted age-stratified serosurveys among residents after a 2013 outbreak that was the largest dengue outbreak on record. The age-weighted prevalence of dengue immunoglobulin G among residents was 49.8% (95% confidence interval: 48.4, 51.1) in 2013 and 48.6% (95% confidence interval: 47.0, 50.0) in 2017; prevalence increased with age. Combining these data with those from previous serosurveys, the year-on-year estimates of the dengue force of infection from 1930 to 2017 revealed a significant decrease from the late 1960s to the mid-1990s, after which the force of infection remained stable at approximately 10 per 1,000 persons per year. The reproduction number (R0) had also declined since the 1960s. The reduction in dengue transmission may be attributed to the sustained national vector program and partly to a change in the age structure of the population. The improved estimated ratio of notified cases to true infections, from 1:14 in 2005-2009 to 1:6 in 2014-2017, signifies that the national notification system, which relies on diagnosed cases, has improved over time. The data also suggest that the magnitudes of dengue epidemics cannot be fairly compared across calendar years and that the current disease control program remains applicable.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Dengue/epidemiologia , Dengue/prevenção & controle , Adolescente , Adulto , Idoso , Teorema de Bayes , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Singapura/epidemiologia
5.
J Org Chem ; 84(11): 7007-7016, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31083909

RESUMO

Neolaxiflorin L (NL) is a low-abundant Isodon 7,20-epoxy- ent-kuarenoid and was found to be a promising anticancer drug candidate in our previous study. In order to study its structure-activity relationship (SAR), a diversity-oriented synthetic route toward two libraries of (±)-NL analogs, including analogs containing different functionalities in the same 7,20-epoxy- ent-kuarene skeleton and analogs with skeletal changes, has been developed. The results of this total synthesis-enabled SAR successfully led to a bioactive alkyne-tagged NL derivative, which could be a useful probe for proteomics studies.


Assuntos
Alcinos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Diterpenos/química , Isodon/química , Alcinos/síntese química , Alcinos/química , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
6.
Artigo em Inglês | MEDLINE | ID: mdl-29667502

RESUMO

A toxicoproteomic study was performed on liver of rats treated with retrorsine (RTS), a representative hepatotoxic pyrrolizidine alkaloid at a toxic dose (140 mg/kg) known to cause severe acute hepatotoxicity. By comparing current data with our previous findings in mild liver lesions of rats treated with a lower dose of RTS, seven proteins and three toxicity pathways of vascular endothelial cell death, which was further verified by observed sinusoidal endothelial cell losses, were found uniquely associated with retrorsine-induced hepatotoxicity. This toxicoproteomic study of acute pyrrolizidine alkaloid intoxication lays a foundation for future investigation to delineate molecular mechanisms of pyrrolizidine alkaloid-induced hepatotoxicity.


Assuntos
Antineoplásicos Fitogênicos/intoxicação , Fígado/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Alcaloides de Pirrolizidina/intoxicação , Animais , Fígado/metabolismo , Masculino , Proteoma/metabolismo , Proteômica , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade
7.
Proteomics ; 16(10): 1557-69, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26970558

RESUMO

Gynostemma pentaphyllum saponins (GpS) have been shown to have anti-cancer activity. However, the underlying mechanisms remain unclear. In this study, we used the Apc(Min) (/+) colorectal cancer (CRC) mouse model to investigate the anti-cancer effect of GpS and we demonstrated that GpS treatment could significantly reduce the number and size of intestinal polyps in Apc(Min) (/+) mice. In order to identify the potential targets and mechanisms involved, a comparative proteomics analysis was performed and 40 differentially expressed proteins after GpS treatment were identified. Bioinformatics analyses suggested a majority of these proteins were involved in processes related to cellular redox homeostasis, and predicted Raf-1 as a potential target of GpS. The upregulation of two proteins known to be involved in redox homeostasis, peroxiredoxin-1 (Prdx1) and peroxiredoxin-2 (Prdx2), and the downregulation of Raf-1 were validated using Western blot analysis. After further investigation of the associated signaling networks, we postulated that the anti-cancer effect of GpS was mediated through the upregulation of Prdx1 and Prdx2, suppression of Ras, RAF/MEK/ERK/STAT, PI3K/AKT/mTOR signaling and modulation of JNK/p38 MAPK signaling. We also examined the potential combinatorial effect of GpS with the chemotherapeutic 5-fluorouracil (5-FU) and found that GpS could enhance the anti-cancer efficacy of 5-FU, further suppressing the number of polyps in Apc(Min/+) mice. Our findings highlight the potential of GpS as an anti-cancer agent, the potential mechanisms of its anti-cancer activities, and its effect as an adjuvant of 5-FU in the chemotherapy of CRC.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/farmacologia , Saponinas/farmacologia , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Colorretais/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Fluoruracila/uso terapêutico , Gynostemma/química , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteoma/metabolismo , Saponinas/uso terapêutico , Transdução de Sinais , Carga Tumoral
8.
Proteomics ; 16(7): 1131-45, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26806198

RESUMO

Macrophages are essential for the maintenance of intestinal homeostasis, and their activation has been proposed to be critical to the pathogenesis of inflammatory bowel disease (IBD). Although there are many recognized mediators of macrophage activation, increasing evidence suggests that macrophages respond to exosome stimulation. Exosomes are 40-150 nm microvesicles released from different cell types and are found in a variety of physiological fluids, including serum. As studies have shown that circulating exosomes participate in intercellular communication and can mediate the immune response, we hypothesized that exosomes may play a role in the pathogenesis of IBD though modulation of macrophage activity. In this study, we used the dextran sulfate sodium (DSS) induced acute colitis mice model to investigate the effect of serum exosomes on macrophages and identify exosome proteins potentially involved in macrophage activation. We treated RAW264.7 macrophages with serum exosomes isolated from dextran sulfate sodium induced mice and found that treatment induced phosphorylation of p38 and ERK and production of tumor necrosis factor α when compared to treatment with exosomes isolated from control mice. Subsequent proteomic analysis identified 56 differentially expressed proteins, a majority of which were acute-phase proteins and immunoglobulins. Bioinformatics analysis suggested these proteins were mainly involved in the complement and coagulation cascade, which has been implicated in macrophage activation. Our findings provide new insight into the role of circulating serum exosomes in acute colitis and contribute to the understanding of macrophage activation in the pathogenesis of IBD.


Assuntos
Colite Ulcerativa/metabolismo , Sulfato de Dextrana/efeitos adversos , Exossomos/efeitos dos fármacos , Exossomos/imunologia , Macrófagos/metabolismo , Proteoma , Animais , Linhagem Celular , Colite Ulcerativa/induzido quimicamente , Ativação do Complemento , Modelos Animais de Doenças , Eletroforese em Gel Bidimensional , Exossomos/química , Exossomos/metabolismo , Feminino , Macrófagos/química , Masculino , Camundongos , Mapas de Interação de Proteínas , Proteoma/análise , Proteoma/imunologia , Proteoma/metabolismo , Proteômica
9.
Proteomics ; 15(17): 3075-86, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25950996

RESUMO

For years, many studies have been conducted to investigate the intracellular response of cells challenged with toxic metal(s), yet, the corresponding secretome responses, especially in human lung cells, are largely unexplored. Here, we provide a secretome analysis of human bronchial epithelial cells (BEAS-2B) treated with cadmium chloride (CdCl2 ), with the aim of identifying secreted proteins in response to Cd toxicity. Proteins from control and spent media were separated by two-dimensional electrophoresis and visualized by silver staining. Differentially-secreted proteins were identified by MALDI-TOF-MS analysis and database searching. We characterized, for the first time, the extracellular proteome changes of BEAS-2B dosed with Cd. Our results unveiled that Cd treatment led to the marked upregulation of molecular chaperones, antioxidant enzymes, enzymes associated with glutathione metabolic process, proteins involved in cellular energy metabolism, as well as tumor-suppressors. Pretreatment of cells with the thiol antioxidant glutathione before Cd treatment effectively abrogated the secretion of these proteins and prevented cell death. Taken together, our results demonstrate that Cd causes oxidative stress-induced cytotoxicity; and the differentially-secreted protein signatures could be considered as targets for potential use as extracellular biomarkers upon Cd exposure.


Assuntos
Brônquios/citologia , Cloreto de Cádmio/toxicidade , Proteínas/metabolismo , Antioxidantes/farmacologia , Brônquios/efeitos dos fármacos , Cloreto de Cádmio/administração & dosagem , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/metabolismo , Meios de Cultura/análise , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glutationa/metabolismo , Glutationa/farmacologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Peroxirredoxinas/metabolismo , Proteínas/análise , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
10.
Chem Res Toxicol ; 28(9): 1715-27, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26280871

RESUMO

Pyrrolizidine alkaloids (PAs) are a group of phytotoxins that can induce human liver injury, particularly hepatic sinusoidal obstruction syndrome (HSOS). To date, the molecular targets of PA-induced HSOS are largely unknown. In this study, retrorsine (RTS), a known hepatotoxic PA, was used as a representative PA for proteomic studies. Toxicological assessment demonstrated that 35 mg/kg RTS (designated as RTS-L) caused early lesions of HSOS at 24 h after dosing. A proteomic approach revealed 17 up-regulated and 31 down-regulated proteins in RTS-L-treated rats. Subsequently, bioinformatic analysis suggested that two proteins, carbamoyl-phosphate synthase (CPS1) (p < 0.05) and ATP synthase subunit beta (ATP5B) (p < 0.01) were associated with RTS-L intoxication. Using immunohistochemical staining, we further verified the down-regulation of CPS1 and ATP5B in RTS-L-treated rats. These findings indicated that CPS1 and ATP5B were altered in the RTS-induced early lesions of HSOS in rats, and therefore, these two proteins and their involved pathways might play important roles in the initiation of HSOS. To the best of our knowledge, our study using a proteomic approach combined with conventional toxicological assessment is the first systems toxicology study on PA-induced HSOS. The results of this study provide novel findings on protein profiles in response to PA exposure, which can serve as a starting point to further investigate potential protein targets and their interactions with PAs to induce HSOS.


Assuntos
Hepatopatia Veno-Oclusiva/induzido quimicamente , Proteômica , Alcaloides de Pirrolizidina/toxicidade , Animais , Análise por Conglomerados , Masculino , Ratos , Ratos Sprague-Dawley
11.
Int J Mol Sci ; 16(4): 8254-65, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25872145

RESUMO

A new [2]pseudorotaxane DB24C8⊃1-H · PF6 with dibenzo[24]crown-8 (DB24C8) crown ether-dibenzylammonium (1-H · PF6) binding which was formed by slippage approach at different solvents and temperature, had been isolated and characterized by NMR spectroscopy and mass spectrometry. The [2]pseudorotaxane DB24C8⊃1-H · PF6 was stable at room temperature. The dissociation rate of [2]pseudorotaxane DB24C8⊃1-H · PF6 could be tuned by using different stimuli such as triethylamine (TEA)/diisopropylethylamine (DIPEA) and dimethyl sulfoxide (DMSO). In particular, the dissociation of [2]pseudorotaxane DB24C8⊃1-H · PF6 by an excess of TEA/DIPEA base mixture possessed a long and sustained, complete dissociation over 60 days. Other stimuli by DMSO possessed a relatively fast dissociation over 24 h.


Assuntos
Rotaxanos/química , Dimetil Sulfóxido/química , Etilaminas/química , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Solventes/química , Temperatura
12.
J Nurs Manag ; 21(4): 605-13, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23406374

RESUMO

AIM: To present the findings of a literature review regarding nurses' intention to leave their employment or the profession. BACKGROUND: The nursing shortage is a problem that is being experienced worldwide. It is a problem that, left unresolved, could have a serious impact on the provision of quality health care. Understanding the reasons why nurses leave their employment or the profession is imperative if efforts to increase retention are to be successful. EVALUATION: Electronic databases were systematically searched to identify English research reports about nurses' intention to leave their employment or the profession. Key results concerning the issue were extracted and synthesized. KEY ISSUES: The diversified measurement instruments, samples and levels of intention to leave caused difficulties in the attempt to compare or synthesize findings. The factors influencing nurses' intention to leave were identified and categorized into organizational and individual factors. CONCLUSIONS: The reasons that trigger nurses' intention to leave are complex and are influenced by organizational and individual factors. Further studies should be conducted to investigate how external factors such as job opportunities correlate with nurses' intention to leave. IMPLICATIONS FOR NURSING MANAGEMENT: The review provides insight that can be useful in designing and implementing strategies to maintain a sustainable workforce in nursing.


Assuntos
Emprego/estatística & dados numéricos , Satisfação no Emprego , Enfermeiras e Enfermeiros/psicologia , Enfermeiras e Enfermeiros/provisão & distribuição , Recursos Humanos de Enfermagem Hospitalar/provisão & distribuição , Esgotamento Profissional , Humanos , Intenção , Cultura Organizacional
13.
Front Pharmacol ; 14: 1227962, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841933

RESUMO

Introduction: Pathological angiogenesis, the abnormal or excessive generation of blood vessels, plays an important role in many diseases including cancer, diabetic retinopathy, psoriasis, and arthritis. Additionally, increasing evidence supports the close linkage between angiogenesis and inflammation. Snake venoms are a rich natural source of biologically active molecules and carry rich potential for the discovery of anti-angiogenic and anti-inflammatory modulators. Methods: Here, we isolated and purified a novel protein, ZK002, from the venom of the snake Deinagkistrodon acutus, and investigated its anti-angiogenic and anti-inflammatory activities and mechanisms. Results: ZK002 was identified as a 30 kDa heterodimeric protein of α and ß chains, which exhibited anti-angiogenic activity in various in vitro assays. Mechanistically, ZK002 inhibited activation of VEGF signaling and related mediators including eNOS, p38, LIMK, and HSP27. ZK002 also upregulated the metalloproteinase inhibitor TIMP3 and inhibited components of the VEGF-induced signaling cascade, PPP3R2 and SH2D2A. The anti-angiogenic activity of ZK002 was confirmed in multiple in vivo models. ZK002 could also inhibit the in vitro expression of pro-inflammatory cytokines, as well as in vivo inflammation in the carrageenin-induced edema rat model. Conclusion: Our findings highlight the potential for further development of ZK002 as a dual function therapeutic against diseases with involvement of pathogenic angiogenesis and chronic inflammation.

14.
Microorganisms ; 10(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35744618

RESUMO

Shifting of virus serotypes and clade replacement events are known to drive dengue epidemics. However, only a few studies have attempted to elucidate the virus attributes that contribute to such epidemics. In 2007, Singapore experienced a dengue outbreak affecting more than 8000 individuals. The outbreak ensued with the shuffling of dominant clades (from clade I to clade II) of Dengue virus 2 (DENV-2) cosmopolitan genotype, at a time when the Aedes premise index was significantly low. Therefore, we hypothesized that clade II had higher epidemic potential and fitness than clade I. To test this hypothesis, we tested the replication and apoptotic qualities of clade I and II isolates in mammalian cells and their ability to infect and disseminate in a field strain of Ae. Aegypti. Our findings indicated that clade II replicated more efficiently in mammalian cells than clade I and possessed higher transmission potential in local vectors. This could collectively improve the epidemic potential of clade II, which dominated during the outbreak in 2007. The findings exemplify complex interactions between the emergence, adaptation and transmission potential of DENV, and testify the epidemiological importance of a deeper understanding of virus and vector dynamics in endemic regions.

15.
Front Nutr ; 9: 816836, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529468

RESUMO

Inflammatory bowel disease (IBD) is a chronic progressive intestinal inflammatory disease, characterized by an altered gut microbiota composition and accompanying alterations in circulatory bile acids. Increasing evidence supports the beneficial effect of probiotics intake on health. Introduction of probiotics to the intestines can modulate gut microbiota composition and in turn regulate the host immune system and modify the inflammatory response. Probiotics can also improve intestinal barrier function and exhibit a positive impact on host physiological and pathological conditions via gut microbiota-derived metabolites. Previous studies have demonstrated that Lactobacillus casei strain Shirota (LcS) treatment could inhibit clinical manifestation of colitis in dextran sulfate sodium (DSS)-induced mice, however, the underlying mechanisms remain unknown. In this study, we employed the DSS-induced acute colitis mouse model to investigate the anti-inflammatory effects of LcS and related mechanisms. Administration of LcS ameliorated the severity of DSS-induced colitis and enhanced intestinal integrity via induction of mucin-2 and occludin expression in colons. Fecal microbiota analysis showed that LcS increased the relative abundance of beneficial bacterial species in colitic mice, whereas the relative abundance of pathobionts was reduced. Additionally, LcS treatment modulated circulating bile acid profiles in colitic mice. In mice treated with LcS, we identified increased levels of primary taurine-conjugated bile acids, including taurocholic acid (TCA) and taurochenodeoxycholic acid (TCDCA). LcS treatment also increased the levels of secondary taurine-conjugated bile acids, including taurodeoxycholic acid (TDCA) and tauroursodeoxycholic acid (TUDCA). Moreover, LcS treatment exhibited a suppressive effect on the hydroxylated primary bile acids α-muricholic acid (α-MCA) and ß-muricholic acid (ß-MCA). We further demonstrated that LcS treatment suppressed the expression of pro-inflammatory mediators interferon-gamma (IFN-γ) and nitric oxide (NO), and increased the expression of the anti-inflammatory mediator interleukin-10 (IL-10) in colon tissues, potentially as a result of altered bile acid profiles. Mechanistically, we showed that LcS treatment suppressed the activation of nuclear factor-kappa B (NF-κB) signaling via stabilization of inhibitor of NF-κB alpha (IκBα). Altogether, we have demonstrated the therapeutic effects of LcS in DSS-induced colitis, providing new insights into its effect on bile acid metabolism and the related anti-inflammatory mechanisms. Our findings provide support for the application of LcS in the treatment of IBD.

16.
Transl Neurodegener ; 11(1): 5, 2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-35101134

RESUMO

Mutations in leucine-rich repeat kinase 2 (LRRK2) and glucocerebrosidase (GBA) represent two most common genetic causes of Parkinson's disease (PD). Both genes are important in the autophagic-lysosomal pathway (ALP), defects of which are associated with α-synuclein (α-syn) accumulation. LRRK2 regulates macroautophagy via activation of the mitogen activated protein kinase/extracellular signal regulated protein kinase (MAPK/ERK) kinase (MEK) and the calcium-dependent adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathways. Phosphorylation of Rab GTPases by LRRK2 regulates lysosomal homeostasis and endosomal trafficking. Mutant LRRK2 impairs chaperone-mediated autophagy, resulting in α-syn binding and oligomerization on lysosomal membranes. Mutations in GBA reduce glucocerebrosidase (GCase) activity, leading to glucosylceramide accumulation, α-syn aggregation and broad autophagic abnormalities. LRRK2 and GBA influence each other: GCase activity is reduced in LRRK2 mutant cells, and LRRK2 kinase inhibition can alter GCase activity in GBA mutant cells. Clinically, LRRK2 G2019S mutation seems to modify the effects of GBA mutation, resulting in milder symptoms than those resulting from GBA mutation alone. However, dual mutation carriers have an increased risk of PD and earlier age of onset compared with single mutation carriers, suggesting an additive deleterious effect on the initiation of PD pathogenic processes. Crosstalk between LRRK2 and GBA in PD exists, but its exact mechanism is unclear. Drugs that inhibit LRRK2 kinase or activate GCase are showing efficacy in pre-clinical models. Since LRRK2 kinase and GCase activities are also altered in idiopathic PD (iPD), it remains to be seen if these drugs will be useful in disease modification of iPD.


Assuntos
Glucosilceramidase , Doença de Parkinson , Autofagia/genética , Glucosilceramidase/genética , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Lisossomos/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/patologia
17.
J Interpers Violence ; 36(11-12): NP6390-NP6410, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-30486717

RESUMO

Previous studies have focused almost exclusively on identifying the antecedents of aggression and violence; as such, there are virtually no experimental data about the psychological consequences of fantasizing aggressive and violent actions. The present experiment aimed to fill this significant informational void in the literature by testing whether aggressive fantasy would influence people's rumination tendency and subjective well-being. We hypothesized that aggressive fantasy would make people more likely to ruminate, which would thereby lower their subjective well-being. To test this prediction, we recruited a sample of participants, who were adults in the United States (overall valid N = 113; 39 men; mean age = 36.27, SD = 11.27), and they were randomly assigned to either the aggressive fantasy condition or the control condition. At the beginning of the experiment, participants were asked to think of a person they despised and describe the characteristics of the despised person. Next, participants in the aggressive fantasy condition fantasized aggressive and violent actions toward the despised target, while participants in the control condition fantasized a control experience. Finally, their state rumination and subjective well-being were assessed. The results showed that, relative to participants who did not fantasize aggression, those who engaged in aggressive fantasy reported higher levels of rumination and lower levels of subjective well-being. Further analysis showed that enhanced rumination significantly mediated the effect of aggressive fantasy on subjective well-being. The present findings contribute to the literature by providing new insights into the psychological consequences of aggressive and violent responses and the underlying mechanism.


Assuntos
Agressão , Transtornos Mentais , Adulto , Cognição , Fantasia , Humanos , Masculino , Violência
18.
J Healthc Leadersh ; 13: 19-26, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33500676

RESUMO

Inequalities in health have existed for many decades and have led to unjust consequences in morbidity and mortality. These have become even more apparent during the COVID-19 pandemic with individuals from black and minority ethnic groups, poorer socioeconomic backgrounds, urban and rurally deprived locations, and vulnerable groups of society suffering the full force of its effects. This review is highlighting the current disparities that exist within different societies, that subsequently demonstrate COVID-19, does in fact, discriminate against disadvantaged individuals. Also explored in detail are the measures that can and should be taken to improve equality and provide equitable distribution of healthcare resources amongst underprivileged communities.

19.
Int J Infect Dis ; 110: 417-425, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34380087

RESUMO

OBJECTIVES: Singapore experienced two major outbreaks of chikungunya in 2008-09 and 2013-14. Despite repeated virus introductions, fresh local outbreaks have not emerged after 2014. The present study reviews the success of chikungunya control in Singapore, despite repeated introduction of virus strains, presence of competent vectors and an immunologically naïve population. METHODS: Chikungunya virus (CHIKV) sequences (421 envelope 1 genes and 56 polyproteins) were analysed to distinguish the indigenous virus groups from 2008 to 2020. Vector surveillance data was used to incriminate the vector/s associated with local outbreaks. The population exposure to CHIKV was determined by assessing the seroprevalence status in three cohorts of sera collected in 2009 (n=2,008), 2013 (n=2,000) and 2017 (n=3,615). RESULTS: Four distinct groups of CHIKV of East, Central and South African genotype have mainly circulated since 2008, transmitted primarily by Aedes albopictus. The age weighted CHIKV IgG prevalence rates were low (1-5%) and showed a non-significant increase from 2009 to 2013, but a significant decrease in 2017. In contrast, the prevalence of CHIKV neutralising antibodies in the population increased significantly from 2009 to 2013, with no significant change in 2017, but the levels remained below 2%. CONCLUSIONS: The evidence suggested that surveillance and vector control strategies implemented were robust to avert severe epidemics, despite repeated introduction of virus strains, presence of competent vectors and an immunologically naïve population.


Assuntos
Vírus Chikungunya , Epidemias , Vírus Chikungunya/genética , Humanos , Mosquitos Vetores , Estudos Soroepidemiológicos , Singapura/epidemiologia , Populações Vulneráveis
20.
Front Pharmacol ; 12: 738139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616300

RESUMO

Inflammatory bowel disease (IBD) is an idiopathic inflammatory disease affecting the gastrointestinal tract. IBD is characterized by courses of relapse and remission, and remains incurable. Although multiple factors are related to the pathogenesis of IBD, disruption of intestinal mucosa homeostasis has been proposed to be a major contributor to IBD, and abnormal activation of immune cells is key for initiation of the inflammatory response. Macrophages are the most abundant immune cells in the intestine. Once activated, they are responsible for secretion of pro-inflammatory cytokines and chemokines to attract circulating monocytes to inflammatory sites, exacerbating the inflammatory response, and leading to tissue damage. Therefore, the suppression of activated macrophages, cytokine/chemokine production, and subsequent monocyte chemotaxis possesses great potential for the treatment of IBD. In our study, we have demonstrated the inhibitory effect of Centipeda minima total extract (CME) on the activation of NF-κB, STAT3, and MAPK signaling in LPS-stimulated RAW264.7 macrophages. In addition, we identified the significant suppressive effect of CME on CCL8 expression in activated macrophages, which potentially contributed to inhibition of monocyte chemotaxis. In the DSS-induced acute colitis mouse model, we have demonstrated the suppressive effect of CME on intestinal macrophage infiltration and its ameliorative effect in IBD. Altogether, we have provided evidence of the therapeutic effect of CME in IBD and the potential of CME for the treatment of IBD.

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