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1.
Chronic Illn ; 18(2): 343-355, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33070630

RESUMO

INTRODUCTION: Chronic disease poses a major problem for the Australian healthcare system as the leading cost-burden and cause of death. Gastroesophageal reflux disease (GORD) typifies the problems with a growing prevalence and cost. We hypothesise that a scintigraphic test could optimise the diagnosis, especially in problematic extraoesophageal disease. MATERIALS AND METHODS: Data was collected from 2 groups of patients. Patients undergoing fundoplication for severe GORD (n = 30) and those with atypical symptoms (n = 30) were studied by scintigraphy and 24-hour oesophageal pH, impedance and manometry. RESULTS: Mean age of cohort was 55.8 years with 40 females and 20 males. Body mass index was a mean of 28.3. DeMeester score was normal in 12/60 with atypical symptoms and abnormal in the rest. Good correlation was shown between scintigraphy and impedance, manometry and distal pH readings. Pulmonary aspiration was shown in 25/60 (15 with atypical symptoms) and LPR in 20/30. Several impedance, manometric and scintigraphic finding were good predictors of lung aspiration of refluxate. CONCLUSION: Scintigraphy provides a good tool for screening patients with typical and atypical symptoms of GORD. It is well correlated with the standard methods for the diagnosis and provides visual evidence of LPR and lung aspiration.


Assuntos
Refluxo Gastroesofágico , Austrália , Doença Crônica , Feminino , Fundoplicatura/métodos , Refluxo Gastroesofágico/diagnóstico , Humanos , Masculino , Manometria , Pessoa de Meia-Idade
2.
J Neurosci ; 41(13): 3025-3038, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33597269

RESUMO

Alzheimer's disease is a devastating neurodegenerative disease with a dramatically increasing prevalence and no disease-modifying treatment. Inflammatory lifestyle factors increase the risk of developing Alzheimer's disease. Zinc deficiency is the most prevalent malnutrition in the world and may be a risk factor for Alzheimer's disease potentially through enhanced inflammation, although evidence for this is limited. Here we provide epidemiological evidence suggesting that zinc supplementation was associated with reduced risk and slower cognitive decline, in people with Alzheimer's disease and mild cognitive impairment. Using the APP/PS1 mouse model of Alzheimer's disease fed a control (35 mg/kg zinc) or diet deficient in zinc (3 mg/kg zinc), we determined that zinc deficiency accelerated Alzheimer's-like memory deficits without modifying amyloid ß plaque burden in the brains of male mice. The NLRP3-inflammasome complex is one of the most important regulators of inflammation, and we show here that zinc deficiency in immune cells, including microglia, potentiated NLRP3 responses to inflammatory stimuli in vitro, including amyloid oligomers, while zinc supplementation inhibited NLRP3 activation. APP/PS1 mice deficient in NLRP3 were protected against the accelerated cognitive decline with zinc deficiency. Collectively, this research suggests that zinc status is linked to inflammatory reactivity and may be modified in people to reduce the risk and slow the progression of Alzheimer's disease.SIGNIFICANCE STATEMENT Alzheimer's disease is a common condition mostly affecting the elderly. Zinc deficiency is also a global problem, especially in the elderly and also in people with Alzheimer's disease. Zinc deficiency contributes to many clinical disorders, including immune dysfunction. Inflammation is known to contribute to the risk and progression of Alzheimer's disease; thus, we hypothesized that zinc status would affect Alzheimer's disease progression. Here we show that zinc supplementation reduced the prevalence and symptomatic decline in people with Alzheimer's disease. In an animal model of Alzheimer's disease, zinc deficiency worsened cognitive decline because of an enhancement in NLRP3-driven inflammation. Overall, our data suggest that zinc status affects Alzheimer's disease progression, and that zinc supplementation could slow the rate of cognitive decline.


Assuntos
Doença de Alzheimer/sangue , Disfunção Cognitiva/sangue , Progressão da Doença , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Zinco/sangue , Adulto , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/dietoterapia , Animais , Células Cultivadas , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/dietoterapia , Suplementos Nutricionais , Feminino , Seguimentos , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Zinco/administração & dosagem , Zinco/deficiência
3.
J Bus Contin Emer Plan ; 15(2): 114-126, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35016746

RESUMO

To extort a ransom payment, ransomware actors must make the threat sufficiently compelling that payment seems like the only option. This is achieved by encrypting or disabling a company's data replicas and backups as well as its production data - data that are essential to the organisation's success. To prevent this happening, it is essential to extend one's thinking beyond the organisation's cyber security incident response plan and disaster recovery programme and give active consideration to a cyber incident recovery risk management (CIR-RM) programme. This paper explores what this requires, including the right thinking, the right approach, the right team and the right plan.


Assuntos
Planejamento em Desastres , Desastres , Segurança Computacional , Gestão de Riscos
4.
Am J Nucl Med Mol Imaging ; 10(6): 342-348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329936

RESUMO

Gastroesophageal reflux disease (GERD) is a common and growing problem in most western countries. It may present with the typical symptoms of heartburn and regurgitation or with the effects of extra-esophageal disease. We have developed and validated a scintigraphic test that evaluates reflux at both sites in patients at high risk of laryngopharyngeal reflux and lung aspiration. We hypothesized that the test may be able to separate physiologic reflux from pathological reflux and examined this possibility in normal asymptomatic volunteers. Asymptomatic volunteers were screened with the Belafsky reflux symptom index (RSI) and entered into the trial if scores were less than 13. 99mTc Phytate was ingested orally and dynamic studies from the pharynx to the stomach were obtained while upright and supine. A delayed study of the thorax was also obtained for lung aspiration of refluxate. Studies were semi-quantitated graphically as time-activity curves. A total of 25 volunteers were studied (13 M, 12 F) with a mean age of 57.5 yr (Range 40-85 yr). None gave a history of heartburn or regurgitation. Mean RSI was 4.1 (range 0-10). Testing showed upright gastroesophageal reflux to the mid-upper esophagus without pharyngeal contamination in 32%. None of the subjects showed supine reflux or lung aspiration. This result corresponds well with intraluminal impedance/pH monitoring in normal volunteers. The scintigraphic reflux test gives similar results to standard intraluminal impedance/pH studies in normal volunteers. A significant proportion of asymptomatic volunteers demonstrate upright reflux only.

5.
Mol Imaging Radionucl Ther ; 29(2): 72-78, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32368878

RESUMO

OBJECTIVES: Fungal pneumonia in the immune competent host is a rarity with few reported cases in the literature. We present a series of 7 cases of recurrent fungal pneumonia in association with allergic fungal rhinosinusitis and gastroesophageal reflux disease (GERD). We hypothesised that recurrent infection may have been transported from the infected paranasal sinuses into the lung by GERD as the process was terminated by surgical fundoplication in 2 of these patients. METHODS: Patients were recruited into the study if they were immune competent and had recurrent fungal pneumonia and GERD. Allergic fungal rhinosinusitis was proven by biopsy. GERD was investigated by a scintigraphic test that assessed local oesophageal disease, lung aspiration and head and neck involvement with a hybrid gamma camera and X-ray computed tomography. RESULTS: All patients were shown to have GERD with 5/7 showing paranasal sinus contamination and 7/7 showing laryngopharyngeal involvement and 6/7 lung aspiration. One patient had characteristics strongly predictive of aspiration. Fundoplication led to cessation of fungal lung infection in two patients. CONCLUSION: Recurrent fungal pneumonia in the immune competent host should raise the possibility of re-infection from the paranasal sinuses, especially in patients with GERD.

6.
Mol Imaging Radionucl Ther ; 29(1): 7-16, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32079383

RESUMO

Objectives: The role of gastroesophageal reflux disease (GERD) in the aetiology of laryngopharyngeal reflux (LPR) is poorly understood and remains a controversial issue. The 24-hour impedance monitoring has shown promise in the evaluation of LPR but is problematic in pharyngeal recording. We have shown the utility of scintigraphic studies in the detection of LPR and lung aspiration of refluxate. Correlative studies were obtained in patients with a strong history of LPR and severe GERD. Methods: A highly selected sequential cohort of patients with a high pre-test probability of LPR/severe GERD who had failed maximal medical therapy were evaluated with 24-hour impedance/pH, manometry and scintigraphic reflux studies. Results: The study group comprised 34 patients (15 M, 19 F) with a mean age of 56 years (range: 28-80 years). The majority had LPR symptoms (mainly cough) in 31 and severe GERD in 3. Impedance bolus clearance and pH studies were abnormal in all patients in the upright and supine position. A high rate of non-acid GERD was detected by impedance monitoring. LOS tone and ineffective oesophageal clearance were found in the majority of patients. Scintigraphic studies showed strong correlations with impedance, pH and manometric abnormalities, with 10 patients showing pulmonary aspiration. Conclusion: Scintigraphic studies appear to be a good screening test for LPR and pulmonary aspiration as there is direct visualisation of tracer at these sites. Impedance studies highlight the importance of non-acidic reflux and bolus clearance in the causation of cough and may allow the development of a risk profile for pulmonary aspiration of refluxate.

9.
Br J Nutr ; 121(9): 961-973, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30791962

RESUMO

Zn plays an important role in maintaining the anti-oxidant status within the heart and helps to counter the acute redox stress that occurs during myocardial ischaemia and reperfusion. Individuals with low Zn levels are at greater risk of developing an acute myocardial infarction; however, the impact of this on the extent of myocardial injury is unknown. The present study aimed to compare the effects of dietary Zn depletion with in vitro removal of Zn (N,N,N',N'-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN)) on the outcome of acute myocardial infarction and vascular function. Male Sprague-Dawley rats were fed either a Zn-adequate (35 mg Zn/kg diet) or Zn-deficient (<1 mg Zn/kg diet) diet for 2 weeks before heart isolation. Perfused hearts were subjected to a 30 min ischaemia/2 h reperfusion (I/R) protocol, during which time ventricular arrhythmias were recorded and after which infarct size was measured, along with markers of anti-oxidant status. In separate experiments, hearts were challenged with the Zn chelator TPEN (10 µm) before ischaemia onset. Both dietary and TPEN-induced Zn depletion significantly extended infarct size; dietary Zn depletion was associated with reduced total cardiac glutathione (GSH) levels, while TPEN decreased cardiac superoxide dismutase 1 levels. TPEN, but not dietary Zn depletion, also suppressed ventricular arrhythmias and depressed vascular responses to nitric oxide. These findings demonstrate that both modes of Zn depletion worsen the outcome from I/R but through different mechanisms. Dietary Zn deficiency, resulting in reduced cardiac GSH, is the most appropriate model for determining the role of endogenous Zn in I/R injury.


Assuntos
Dieta/efeitos adversos , Glutationa/metabolismo , Isquemia Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/etiologia , Zinco/deficiência , Animais , Coração/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
10.
Front Biosci (Landmark Ed) ; 22(4): 623-643, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27814637

RESUMO

As a nutritionally essential metal ion, zinc (Zn) not only constitutes a structural element for more than 3000 proteins but also plays important regulatory functions in cellular signal transduction. Zn homeostasis is tightly controlled by regulating the flux of Zn across cell membranes through specific transporters, i.e. ZnT and ZIP family proteins. Zn deficiency and malfunction of Zn transporters have been associated with many chronic diseases including cancer. However, the mechanisms underlying Zn regulatory functions in cellular signaling and their impact on the pathogenesis and progression of cancers remain largely unknown. In addition to these acknowledged multifunctions, Zn modulates a wide range of ion channels that in turn may also play an important role in cancer biology. The goal of this review is to propose how zinc deficiency, through modified Zn homeostasis, transporter activity and the putative regulatory function of Zn can influence ion channel activity, and thereby contribute to carcinogenesis and tumorigenesis. This review intends to stimulate interest in, and support for research into the understanding of Zn-modulated channels in cancers, and to search for novel biomarkers facilitating effective clinical stratification of high risk cancer patients as well as improved prevention and therapy in this emerging field.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Canais Iônicos/metabolismo , Neoplasias/metabolismo , Zinco/metabolismo , Animais , Homeostase , Humanos , Proteínas de Neoplasias/metabolismo , Proteína ORAI1/metabolismo , Canais de Potássio/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Zinco/deficiência
11.
World J Gastroenterol ; 21(12): 3619-27, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25834329

RESUMO

AIM: To investigate the utility of scintigraphic studies in predicting response to laparoscopic fundoplication (LF) for chronic laryngopharyngeal reflux symptoms. METHODS: Patients with upper aero-digestive symptoms that remained undiagnosed after a period of 2 mo were studied with conventional pH and manometric studies. Patients mainly complained of cough, sore throat, dysphonia and globus. These patients were imaged after ingestion of 99m-technetium diethylene triamine pentaacetic acid. Studies were quantified with time activity curves over the pharynx, upper and lower oesophagus and background. Late studies of the lungs were obtained for aspiration. Patients underwent LF with post-operative review at 3 mo after surgery. RESULTS: Thirty four patients (20 F, 14 M) with an average age of 57 years and average duration of symptoms of 4.8 years were studied. Twenty four hour pH and manometry studies were abnormal in all patients. On scintigraphy, 27/34 patients demonstrated pharyngeal contamination and a rising or flat pharyngeal curve. Lung aspiration was evident in 50% of patients. There was evidence of pulmonary aspiration in 17 of 34 patients in the delayed study (50%). Pharyngeal contamination was found in 27 patients. All patients with aspiration showed pharyngeal contamination. In the 17 patients with aspiration, graphical time activity curve showed rising activity in the pharynx in 9 patients and a flat curve in 8 patients. In those 17 patients without pulmonary aspiration, 29% (5 patients) had either a rising or flat pharyngeal graph. A rising or flat curve predicted aspiration with a positive predictive value of 77% and a negative predictive value of 100%. Over 90% of patients reported a satisfactory symptomatic response to LF with an acceptable side-effect profile. CONCLUSION: Scintigraphic reflux studies offer a good screening tool for pharyngeal contamination and aspiration in patients with gastroesophageal reflux disease.


Assuntos
Refluxo Gastroesofágico/diagnóstico por imagem , Refluxo Laringofaríngeo/diagnóstico por imagem , Adulto , Idoso , Análise por Conglomerados , Monitoramento do pH Esofágico , Feminino , Fundoplicatura/métodos , Refluxo Gastroesofágico/fisiopatologia , Refluxo Gastroesofágico/cirurgia , Humanos , Laparoscopia , Refluxo Laringofaríngeo/fisiopatologia , Refluxo Laringofaríngeo/cirurgia , Masculino , Manometria , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Cintilografia , Compostos Radiofarmacêuticos , Aspiração Respiratória de Conteúdos Gástricos/diagnóstico por imagem , Pentetato de Tecnécio Tc 99m , Fatores de Tempo , Resultado do Tratamento
12.
Genes Nutr ; 10(1): 446, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25446494

RESUMO

Low B vitamin status is linked with human vascular disease. We employed a proteomic and biochemical approach to determine whether nutritional folate deficiency and/or hyperhomocysteinemia altered metabolic processes linked with atherosclerosis in ApoE null mice. Animals were fed either a control fat (C; 4 % w/w lard) or a high-fat [HF; 21 % w/w lard and cholesterol (0/15 % w/w)] diet with different B vitamin compositions for 16 weeks. Aorta tissue was prepared and global protein expression, B vitamin, homocysteine and lipoprotein status measured. Changes in the expression of aorta proteins were detected in response to multiple B vitamin deficiency combined with a high-fat diet (P < 0.05) and were strongly linked with lipoprotein concentrations measured directly in the aorta adventitia (P < 0.001). Pathway analysis revealed treatment effects in the aorta-related primarily to cytoskeletal organisation, smooth muscle cell adhesion and invasiveness (e.g., fibrinogen, moesin, transgelin, vimentin). Combined B vitamin deficiency induced striking quantitative changes in the expression of aorta proteins in atherosclerotic ApoE null mice. Deregulated expression of these proteins is associated with human atherosclerosis. Cellular pathways altered by B vitamin status included cytoskeletal organisation, cell differentiation and migration, oxidative stress and chronic inflammation. These findings provide new insight into the molecular mechanisms through which B vitamin deficiency may accelerate atherosclerosis.

13.
Pract Lab Med ; 1: 28-34, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28932796

RESUMO

OBJECTIVES: Despite several publications on the analytical performance of high-sensitivity cardiac troponin (hs-cTn) assays, there has been little information on how laboratories should validate and implement these assays into clinical service. Our study provides a practical approach for the validation and implementation of a hs-cTn assay across a large North American City. DESIGN AND METHODS: Validation for the Abbott ARCHITECT hs-cTnI assay (across 5 analyzers) consisted of verification of limit of blank (LoB), precision (i.e., coefficient of variation; CV) testing at the reported limit of detection (LoD) and within and outside the 99th percentile, linearity testing, cTnI versus hs-cTnI patient comparison within and between analyzers (Passing and Bablok and non-parametric analyses). Education, clinical communications, and memorandums were issued in advance to inform all staff across the city as well as a selected reminder the day before live-date to important users. All hospitals switched to the hs-cTnI assay concurrently (the contemporary cTnI assay removed) with laboratory staff instructed to repeat samples previously measured with the contemporary cTnI assay with the hs-cTnI assay only by physician request. RESULTS: Across the 5 analyzers and 6 reagent packs the overall LoB was 0.6 ng/L (n=60) with a CV of 33% at an overall mean of 1.2 ng/L (n=60; reported LoD=1.0 ng/L), with linearity demonstrated from 45,005 ng/L to 1.1 ng/L. Precision testing with a normal patient-pool QC material (mean range across 5 analyzers was 3.9-4.4 ng/L) yielded a range of CVs from 7% to 10% (within-run) and CVs from 7% to 18% (between-run) with the high patient-pool QC material (mean range across 5 analyzers was 29.6-36.3 ng/L) yielding a range of CVs from 2% to 5% (within-run) and CVs from 4% to 8% (between-run). There was agreement between hs-cTnI versus cTnI with the patient samples (slope ranges: 0.89-1.03; intercept ranges: 1.9-3.8 ng/L), however, the median CV on patient samples <100 ng/L across the analyzers was 5.6% for hs-cTnI versus 18.7% for the contemporary assay (p<0.001). Following the switch to hs-cTnI testing, no requests for repeat measurements were received. CONCLUSIONS: Validation and implementation of hs-cTnI testing across multiple sites requires collaboration within the laboratories and between hospital laboratories and clinical staff.

14.
Curr Opin Clin Nutr Metab Care ; 17(5): 431-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25023186

RESUMO

PURPOSE OF REVIEW: Elemental imaging techniques are capable of showing the spatial distribution of elements in a sample. Their application in biomedical sciences is promising, but they are not yet widely employed. The review gives a short overview about techniques available and then focuses on the advantages of using laser ablation inductively coupled plasma mass spectrometry for elemental bioimaging. Current examples for the use of elemental imaging with medical context are given to illustrate the potential of this type of analysis for clinical applications. RECENT FINDINGS: Recently, synchrotron-based techniques and laser ablation inductively coupled plasma mass spectrometry have been successfully applied to analyse the spatial distribution of elements in biological samples of medical relevance. SUMMARY: Elemental bioimaging methods have a great potential for medical applications. They are complementary to molecular imaging and histological staining and are especially attractive when used in combination with stable isotope tracer experiments.


Assuntos
Diagnóstico por Imagem/métodos , Oligoelementos , Humanos , Terapia a Laser/métodos , Espectrometria de Massas/métodos
16.
FASEB J ; 27(9): 3672-82, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23729592

RESUMO

Mild dietary zinc deprivation in humans and rodents has little effect on blood plasma zinc levels, and yet cellular consequences of zinc depletion can be detected in vascular and other tissues. We proposed that a zinc-regulated humoral factor might mediate the effects of zinc deprivation. Using a novel approach, primary rat vascular smooth muscle cells (VSMCs) were treated with plasma from zinc-deficient (<1 mg Zn/kg) or zinc-adequate (35 mg Zn/kg, pair-fed) adult male rats, and zinc levels were manipulated to distinguish direct and indirect effects of plasma zinc. Gene expression changes were analyzed by microarray and qPCR, and incubation of VSMCs with blood plasma from zinc-deficient rats strongly changed the expression of >2500 genes, compared to incubation of cells with zinc-adequate rat plasma. We demonstrated that this effect was caused by a low-molecular-weight (∼2-kDa) zinc-regulated humoral factor but that changes in gene expression were mostly reversed by adding zinc back to zinc-deficient plasma. Strongly regulated genes were overrepresented in pathways associated with immune function and development. We conclude that zinc deficiency induces the production of a low-molecular-weight humoral factor whose influence on VSMC gene expression is blocked by plasma zinc. This factor is therefore under dual control by zinc.


Assuntos
Zinco/sangue , Zinco/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Células Cultivadas , Ingestão de Alimentos/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Masculino , Peso Molecular , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Reação em Cadeia da Polimerase , Ratos , Zinco/deficiência
17.
Cardiovasc Res ; 99(3): 525-34, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23667188

RESUMO

AIMS: Dietary zinc deficiency has been associated with the development of atherosclerosis although the effects on vascular smooth muscle cells (VSMCs), important in maintaining atherosclerotic plaque integrity, are unknown. The main aim of this study was to elucidate the effect of a zinc-deficient environment on VSMCs using an in vivo model. METHODS AND RESULTS: Rats were maintained for 2 weeks on a marginally zinc-deficient diet which resulted in a significant reduction in plasma zinc levels. Large arteries from zinc-deficient rats had significantly increased apoptosis within the VSMC layers compared with arteries from rats on a zinc-adequate diet. This apoptosis occurred in parallel with a known apoptotic pathway, namely dephosphorylation of the pro-apoptotic protein Bcl-2-associated death promoter protein (BAD). Activation of extracellular signal-regulated kinase (ERK)1/2, which maintains BAD phosphorylation as a pro-survival mechanism, was decreased in arteries from zinc-deficient rats. The mechanisms of this in vivo effect were investigated in vitro. Cultured rat VSMCs incubated with plasma from zinc-deficient rats similarly resulted in increased apoptosis in parallel with BAD dephosphorylation and decreased ERK1/2 activation. Further related apoptotic mechanisms induced by plasma from zinc-deficient rats involved a prolonged rise in [Ca²âº]i leading to subsequent activation of the phosphatase calcineurin. Calcineurin activation was required to dephosphorylate BAD. In addition, an increase in oxidative stress contributed to the apoptotic effect induced by plasma from zinc-deficient rats. CONCLUSION: In conclusion, a marginally zinc-deficient diet is pro-apoptotic for VSMCs and this may contribute to cardiovascular disease.


Assuntos
Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Zinco/deficiência , Animais , Apoptose/fisiologia , Calcineurina/metabolismo , Cálcio/metabolismo , Doenças das Artérias Carótidas/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Sistema de Sinalização das MAP Quinases , Estresse Oxidativo , Fosforilação , Ratos , Zinco/sangue , Proteína de Morte Celular Associada a bcl/metabolismo
18.
Atherosclerosis ; 228(1): 46-52, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23466072

RESUMO

BACKGROUND: The accelerated proliferation of vascular smooth muscle cells (VSMCs) is a contributor for atherosclerosis by thickening the vascular wall. Since zinc modulation of VSMC proliferation has not been clarified, this study investigated whether zinc affects VSMC proliferation. METHODS AND RESULTS: Both a rat aorta origin vascular smooth muscle cell line (A7r5 VSMCs) and primary VSMCs which were collected from rat aorta (pVSMCs) were cultured with zinc (0-50 µM Zn) for short- (≤12 d) and long-term (28 d) periods under normal non-calcifying (0 or 1 mM P) or calcifying (>2 mM P) P conditions. Mouse vascular endothelial cells (MS I cells) were also cultured (under 0-50 µM Zn and 10 mM P for 20 d) to compare with VSMC cultures. While during short-term culture of VSMCs, zinc deprivation decreased cell proliferation in a zinc-concentration manner both under non-calcifying and calcifying conditions in A7r5 and pVSMCs (P < 0.05), during long-term cultures (28 d), A7r5 VSMC proliferation was inversely related to medium zinc concentration under normal physiological P conditions (regression coefficient r(2) = -0.563, P = 0.012). The anti-cell proliferative effect of zinc supplementation (>50 µM) was VSMC-specific. Long-term (35 d), low zinc treatment down-regulated JNK expression and activation, while not affecting ERK1/2 MAPK signaling in A7r5 VSMCs. CONCLUSION: The results showed that chronic zinc deprivation accelerated VSMC proliferation, perhaps due to down-regulation of MAPK-JNK signaling, and that the anti-cell proliferative role of zinc is VSMC-specific. The findings suggested that zinc may have anti-VSMC proliferative properties in atherosclerosis.


Assuntos
Proliferação de Células/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Zinco/deficiência , Zinco/farmacologia , Animais , Aorta/citologia , Cálcio/metabolismo , Meios de Cultura/farmacologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Cultura Primária de Células , Ratos , Fator de Transcrição STAT3/metabolismo , Fatores de Tempo
19.
Metallomics ; 4(10): 1057-63, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22907676

RESUMO

Zinc stable isotope tracers (67Zn and 7°Zn) were injected into rats at two different time points to investigate the feasibility of using tracers to study zinc kinetics at the microscale within distinct tissue features. Laser ablation coupled to multi-collector ICP-MS was used to analyse average isotope ratios in liver thin sections and to generate bio-images showing zinc isotope ratio distribution in brain thin sections. Average isotope ratios of all samples from treated animals were found to be statistically different (P < 0.05) from samples from untreated control animals. Furthermore, differing isotope ratios in physiological features of the brain, namely hippocampus, amygdala, cortex and hypothalamus, were identified. This indicates that these regions differ in their zinc metabolism kinetics. While cortex and hypothalamus contain more tracer two days after injection than 14 days after injection, the opposite is true for hippocampus and amygdala. This study showed that stable isotope tracer experiments can be combined with laser ablation MC-ICP-MS to measure trace element kinetics in tissues at a microscale level.


Assuntos
Química Encefálica , Encéfalo/metabolismo , Imagem Molecular/métodos , Espectrometria de Massas em Tandem/métodos , Isótopos de Zinco/farmacocinética , Animais , Encéfalo/citologia , Estudos de Viabilidade , Cinética , Fígado/química , Fígado/metabolismo , Ratos
20.
Mol Nutr Food Res ; 56(7): 1097-105, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22760982

RESUMO

SCOPE: Cardiovascular health is strongly influenced by diet. Zinc has antioxidant and anti-inflammatory properties but its long-term influence on vascular health at dietary intake levels relevant to the human population in developed countries has not been studied. We investigated the influence of suboptimal zinc intake in a Western-type diet on the development of vascular inflammation and arterial plaque in apoE knock-out (AEKO) mice. METHODS AND RESULTS: Weanling AEKO and wild-type (WT) controls were given high saturated fat (21% w/w) and high cholesterol (0.15%) semi-synthetic diets containing 3 or 35 mg Zn/kg (AEKO and WT) or 8 mg Zn/kg (AEKO only) for over 6 months. AEKO mice on zinc intakes of 3 and 8 mg Zn/kg (suboptimal zinc) developed significantly (p < 0.05) more aortic plaque than AEKO mice consuming 35 mg Zn/kg (adequate zinc). Circulating levels of interleukin-1ß, interleukin-6 and soluble vascular adhesion molecule-1 were significantly (p < 0.05) raised at the lowest zinc intake in AEKO mice, as compared to zinc-adequate controls. Plasma total cholesterol and total protein were also significantly (p < 0.05) increased at the lowest zinc intake. CONCLUSION: We propose that suboptimal dietary zinc intake raises circulating pro-atherogenic lipoprotein levels that promote vascular inflammation and enhance arterial plaque formation.


Assuntos
Aterosclerose/etiologia , Dieta/efeitos adversos , Modelos Animais de Doenças , Vasculite/etiologia , Zinco/deficiência , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/uso terapêutico , Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/sangue , Aterosclerose/imunologia , Aterosclerose/prevenção & controle , Calcinose/etiologia , Calcinose/imunologia , Calcinose/patologia , Calcinose/prevenção & controle , Dieta Aterogênica/efeitos adversos , Interleucinas/sangue , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/imunologia , Placa Aterosclerótica/patologia , Placa Aterosclerótica/prevenção & controle , Distribuição Aleatória , Índice de Gravidade de Doença , Molécula 1 de Adesão de Célula Vascular/sangue , Vasculite/sangue , Vasculite/imunologia , Vasculite/prevenção & controle , Zinco/administração & dosagem , Zinco/uso terapêutico
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