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1.
Clin Immunol ; 244: 109118, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36084852

RESUMO

To enable accurate, high-throughput and longer-term studies of the immunopathogenesis of type 1 diabetes (T1D), we established three in-vitro islet-immune injury models by culturing spheroids derived from primary human islets with proinflammatory cytokines, activated peripheral blood mononuclear cells or HLA-A2-restricted preproinsulin-specific cytotoxic T lymphocytes. In all models, ß-cell function declined as manifested by increased basal and decreased glucose-stimulated insulin release (GSIS), and decreased intracellular insulin content. Additional hallmarks of T1D progression such as loss of the first-phase insulin response (FFIR), increased proinsulin-to-insulin ratios, HLA-class I expression, and inflammatory cytokine release were also observed. Using these models, we show that liraglutide, a glucagon-like peptide 1 receptor agonist, prevented loss of GSIS under T1D-relevant stress, by preserving the FFIR and decreasing immune cell infiltration and cytokine secretion. Our results corroborate that liraglutide mediates an anti-inflammatory effect that aids in protecting ß-cells from the immune-mediated attack that leads to T1D.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Glucose/metabolismo , Antígeno HLA-A2 , Humanos , Insulina , Células Secretoras de Insulina/metabolismo , Leucócitos Mononucleares/metabolismo , Liraglutida/metabolismo , Liraglutida/farmacologia , Proinsulina/metabolismo
2.
Addict Biol ; 26(2): e12901, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32293773

RESUMO

Overdose of stimulant drugs has been associated with increased risk of adverse cardiovascular events (ACVE), some of which may be ascribed to endothelial dysfunction. The aims of this study were to evaluate biomarkers of endothelial dysfunction in emergency department (ED) patients with acute cocaine overdose and to assess the association between in-hospital ACVE in ED patients with any acute drug overdose. This was a prospective consecutive cohort study over 9 months (2015-2016) at two urban, tertiary-care hospital EDs. Consecutive adults (≥18 years) presenting with suspected acute drug overdose were eligible and separated into three groups: cocaine (n = 47), other drugs (n = 128), and controls (n = 11). Data were obtained from medical records and linked to waste serum specimens, sent as part of routine clinical care, for biomarker analysis. Serum specimens were collected and analyzed using enzyme-linked immunosorbent assay kit for three biomarkers of endothelial dysfunction: (a) endothelin-1 (ET-1), (b) regulated upon activation normal T cell expressed and secreted (RANTES), and (c) soluble intercellular adhesion molecule-1 (siCAM-1). Mean siCAM was elevated for cocaine compared with controls and other drugs (p < .01); however, mean RANTES and ET-1 levels were not significantly different for any drug exposure groups. Receiver operating characteristics curve analysis for prediction of in-hospital ACVE revealed excellent performance of siCAM-1 (area under curve, 0.86; p < .001) but lack of predictive utility for either RANTES or ET-1. These results suggest that serum siCAM-1 is a viable biomarker for acute cocaine overdose and that endothelial dysfunction may be an important surrogate for adverse cardiovascular events following any drug overdose.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Cocaína/intoxicação , Overdose de Drogas/sangue , Endotélio Vascular/efeitos dos fármacos , Adulto , Biomarcadores , Quimiocina CCL5/sangue , Serviço Hospitalar de Emergência , Endotelina-1/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Molécula 1 de Adesão Intercelular/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Fatores de Risco , Centros de Atenção Terciária
3.
Psychiatr Q ; 92(3): 1093-1107, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33587260

RESUMO

The successful treatment of depressive disorders critically depends on adherence to prescribed treatment regimens. Despite increasing rates of antidepressant medication prescription, adherence to the full treatment course remains poor. Rates of antidepressant non-adherence are higher for uninsured patients and members of some marginalized racial and ethnic communities due to factors such as inequities in healthcare and access to insurance. Among patients treated in a free, student-run and faculty-supervised clinic serving uninsured patients in a majority Hispanic community in East Harlem, adherence rates are lower than those observed in patients with private or public New York State health insurance coverage. A prior study of adherence in these patients revealed that difficulty in obtaining medications from an off-site hospital pharmacy was a leading factor that patients cited for non-adherence. To alleviate this barrier to obtaining prescriptions, we tested the effectiveness of on-site, in-clinic medication dispensing for improving antidepressant medication adherence rates among uninsured patients. We found that dispensing medications directly to patients in clinic was associated with increased visits at which patients self-reported proper adherence and increased overall adherence rates. Furthermore, we found evidence that higher rates of antidepressant medication adherence were associated with more favorable treatment outcomes. All patients interviewed reported increased satisfaction with on-site dispensing. Overall, this study provides promising evidence that on-site antidepressant dispensing in a resource-limited setting improves medication adherence rates and leads to more favorable treatment outcomes with enhanced patient satisfaction.


Assuntos
Antidepressivos , Pessoas sem Cobertura de Seguro de Saúde , Antidepressivos/uso terapêutico , Prescrições de Medicamentos , Humanos , Adesão à Medicação , Satisfação do Paciente
4.
Neuroimage ; 218: 116976, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32464290

RESUMO

As the population ages, the incidence of age-related neurological diseases and cognitive decline increases. To further understand disease-related changes in brain function it is advantageous to examine brain activity changes in healthy aging rodent models to permit mechanistic investigation. Here, we examine the suitability, in rodents, of using a novel, minimally invasive anaesthesia protocol in combination with a functional MRI protocol to assess alterations in neuronal activity due to physiological aging. 11 Wistar Han female rats were studied at 7, 9, 12, 15 and 18 months of age. Under an intravenous infusion of propofol, animals underwent functional magnetic resonance imaging (fMRI) and functional magnetic resonance spectroscopy (fMRS) with forepaw stimulation to quantify neurotransmitter activity, and resting cerebral blood flow (CBF) quantification using arterial spin labelling (ASL) to study changes in neurovascular coupling over time. Animals showed a significant decrease in size of the active region with age (P â€‹< â€‹0.05). fMRS results showed a significant decrease in glutamate change with stimulation (ΔGlu) with age (P â€‹< â€‹0.05), and ΔGlu became negative from 12 months onwards. Global CBF remained constant for the duration of the study. This study shows age related changes in the blood oxygen level dependent (BOLD) response in rodents that correlate with those seen in humans. The results also suggest that a reduction in synaptic glutamate turnover with age may underlie the reduction in the BOLD response, while CBF is preserved.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Modelos Animais , Neuroimagem/métodos , Anestésicos Intravenosos/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Feminino , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Propofol/farmacologia , Ratos , Ratos Wistar
5.
BMC Neurosci ; 21(1): 5, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996121

RESUMO

BACKGROUND: Cerebral ischemic stroke is a significant cause of morbidity and mortality. Sex differences exist following stroke in terms of incidence, symptoms, outcomes and response to some treatments. Importantly, molecular mechanisms of injury, activated following ischemia may differ between the sexes and if so may account, at least in part, for sex differences seen in treatment response. Here we aimed to determine, using single-sex organotypic hippocampal slice cultures, whether the effectiveness of a potential treatment option, i.e. sex steroids, exhibited any sexual dimorphism and whether sex affected the mechanisms of apoptosis activated following ischemia. RESULTS: Following exposure to ischemia, male-derived tissue exhibited higher levels of cell death than female-derived tissue. Various sex steroid hormones, i.e. progesterone, allopregnanolone, and estradiol, were protective in terms of reducing the amount of cell death in male- and female-derived tissue whereas medoxyprogesterone acetate (MPA) was only protective in female-derived tissue. The protective effect of progesterone was abolished in the presence of finasteride, a 5α-reductase inhibitor, suggesting it was largely mediated via its conversion to allopregnanolone. To test the hypothesis that sex differences exist in the activation of specific elements of the apoptotic pathway activated following ischemia we administered Q-VD-OPH, a caspase inhibitor, or PJ34, an inhibitor of poly (ADP ribose) polymerase (PARP). Caspase inhibition was only effective, in terms of reducing cell death, in female-derived tissue, whereas PARP inhibition was only protective in male-derived tissue. However, in both sexes, the protective effects of progesterone and estradiol were not observed in the presence of either caspase or PARP inhibition. CONCLUSIONS: Sex differences exist in both the amount of cell death produced and those elements of the cell death pathway activated following an ischemic insult. There are also some sex differences in the effectiveness of steroid hormones to provide neuroprotection following an ischemic insult-namely MPA was only protective in female-derived tissue. This adds further support to the notion sex is an important factor to consider when investigating future drug targets for CNS disorders, such as ischemic stroke.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Neuroesteroides/administração & dosagem , Caracteres Sexuais , Acidente Vascular Cerebral/metabolismo , Animais , Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos
6.
J Strength Cond Res ; 33(8): 2217-2222, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31343602

RESUMO

Gibson, C, Hindle, C, McLay-Cooke, R, Slater, J, Brown, R, Smith, B, Baker, D, Healey, P, and Black, K. Body image among elite rugby union players. J Strength Cond Res 33(8): 2217-2222, 2019-There is limited information on the risk of eating disorders (EDs) and body image of elite male athletes. However, research studies suggest that there are some athletes who have poor body image and they may be at increased risk of developing EDs. Therefore, the current study investigated risk of EDs, body image, and the relationship with age, in elite rugby union players during their preseason training period. This cross-sectional study was undertaken at the start of the preseason among elite rugby union players in New Zealand. Twenty-six professional rugby union players completed a 49-item questionnaire on body image and disordered eating. A "body image score" was calculated from questionnaire subscales including "drive for thinness," "bulimia," and "body dissatisfaction," with total scores above 20 indicative of poor body image. Body image scores varied from 8 to 39 out of a possible 0-100. Disordered eating behaviors were reported, including binge eating at least once a week (15%, n = 4/26), pathogenic weight control use (4%, n = 1/26), and avoidance of certain foods (77%, n = 20/26). There was a statistically significant inverse association between the bulimia subscale and age (p = 0.034). At the start of the preseason training period, many elite rugby union players experience disturbances in body image. The prevalence of disordered eating behaviors is of concern, and needs to be minimized due to the negative impact on health and performance. A focus on assessment and education of younger male rugby players may be required to reduce disordered eating patterns.


Assuntos
Atletas/psicologia , Imagem Corporal/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Futebol Americano/psicologia , Adulto , Fatores Etários , Estudos Transversais , Comportamento Alimentar , Humanos , Masculino , Nova Zelândia , Prevalência , Adulto Jovem
7.
Diabetologia ; 60(8): 1475-1482, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28455654

RESUMO

AIMS/HYPOTHESIS: Insulin is widely considered to be a driver antigen in type 1 diabetes in humans and in mouse models of the disease. Therefore, insulin or insulin analogues are candidates for tolerogenic drugs to prevent disease onset in individuals with risk of diabetes. Previous experiments have shown that autoimmune diabetes can be prevented in NOD mice by repeated doses of insulin administered via an oral, nasal or parenteral route, but clinical trials in humans have not succeeded. The hypoglycaemic activity of insulin is dose-limiting in clinical studies attempting tolerance and disease prevention. Here, we aimed to investigate the therapeutic potential of metabolically inactive insulin analogue (MII) in NOD mice. METHODS: The tolerogenic potential of MII to prevent autoimmune diabetes was studied by administering multiple i.v. or s.c. injections of MII to non-diabetic 7-12-week-old female NOD mice in three geographical colony locations. The incidence of diabetes was assessed from daily or weekly blood glucose measurements. The effect of MII on insulin autoantibody levels was studied using an electrochemiluminescence-based insulin autoantibody assay. The effect on the number of insulin-reactive CD8+ and CD4+ T lymphocytes in peripheral lymphoid tissue was studied with MHC class I and MHC class II tetramers, respectively. RESULTS: We found that twice-weekly s.c. administration of MII accelerates rather than prevents diabetes. High-dose i.v. treatment did not prevent disease or affect insulin autoantibody levels, but it increased the amount of insulin-reactive CD4+ T lymphocytes in peripheral lymphoid tissue. CONCLUSIONS/INTERPRETATION: Our data suggest that parenteral MII, even when used in high doses, has little or no therapeutic potential in NOD mice and may exacerbate disease.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Insulina/uso terapêutico , Animais , Autoanticorpos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Feminino , Citometria de Fluxo , Hibridomas/metabolismo , Insulina/análogos & derivados , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos
8.
J Autoimmun ; 84: 65-74, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28711285

RESUMO

Immunotherapy for type 1 diabetes (T1D) has previously focused on suppressing the autoimmune response against pancreatic beta cells to preserve endogenous insulin production and regulate glucose levels. With increased attention toward combination therapy strategies, studies indicate the multifunctional cytokine interleukin-21 (IL-21) may be a suitable target as an immuno-modulatory arm, while glucagon-like peptide-1 receptor (GLP-1R) agonists may be appropriate as a beta cell protective arm in combination therapy for T1D. We report here that treatment with anti-IL-21 monoclonal antibody delays diabetes onset in the spontaneous non-obese diabetic (NOD) and NOD.scid adoptive transfer models, while its effect in reversing recent-onset hyperglycemia is limited. However, the combination of anti-IL-21 plus the GLP-1R agonist liraglutide is effective in reversing established disease compared to either monotherapy in both the NOD and rat insulin promotor-lymphocytic choriomeningitis virus glycoprotein (RIP-LCMV-GP) models of autoimmune diabetes. Enhanced efficacy is particularly evident in severely hyperglycemic mice, with return to normoglycemia remaining stable for the majority of mice even after therapy is withdrawn. Importantly, increased beta cell proliferation does not appear to be the predominant mechanism. In conclusion, combination therapy with anti-IL-21 and liraglutide is able to consistently reverse disease in mouse models of T1D. The observed effects rival the most effective experimental disease-modifying treatments tested in preclinical studies.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Diabetes Mellitus Tipo 1/terapia , Hiperglicemia/terapia , Imunoterapia/métodos , Células Secretoras de Insulina/imunologia , Interleucinas/imunologia , Liraglutida/uso terapêutico , Animais , Diabetes Mellitus Tipo 1/imunologia , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Humanos , Hiperglicemia/imunologia , Insulina/genética , Insulina/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos
9.
Clin Immunol ; 164: 28-33, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26821303

RESUMO

Studies have shown oral insulin prevents type 1 diabetes (T1D) in mouse models, however human trials were inconclusive. We tested the ability of different insulins to prevent T1D in non-obese diabetic mice. Mice received oral insulin or PBS twice weekly and disease was monitored. Contrary to previous studies, no insulin tested showed significant ability to prevent T1D, nor did testing of linked suppression in a delayed type hypersensitivity model have reproducible effect. To investigate delivery of antigen within the GI tract, blue dye was fed to mice. Dye traveled 5-8 cm from stomach to small intestine within 10s, suggesting orally administered antigen may not get digested in the stomach in mice. Insulin incubated with jejunum extracts was instantly digested. Thus, in humans large doses of insulin may be required to achieve tolerance as antigen may be more vulnerable to digestion in the stomach even before reaching the small intestine.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Administração Oral , Animais , Antígenos/imunologia , Glicemia/análise , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Tipo 1/sangue , Feminino , Hemocianinas/imunologia , Humanos , Hipersensibilidade Tardia/imunologia , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/uso terapêutico , Tolerância Imunológica , Insulina/farmacocinética , Insulina/uso terapêutico , Mucosa Intestinal/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Suínos
10.
J Immunol ; 193(3): 1268-77, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24958899

RESUMO

Sterile protection against malaria infection can be achieved through vaccination of mice and humans with whole Plasmodium spp. parasites. One such method, known as infection-treatment-vaccination (ITV), involves immunization with wild type sporozoites (spz) under drug coverage. In this work, we used the different effects of antimalarial drugs chloroquine (CQ) and artesunate (AS) on blood stage (BS) parasites to dissect the stage-specific immune responses in mice immunized with Plasmodium yoelii spz under either drug, as well as their ability to protect mice against challenge with spz or infected RBCs (iRBCs). Whereas CQ-ITV induced sterile protection against challenge with both spz and iRBCs, AS-ITV only induced sterile protection against spz challenge. Importantly, AS-ITV delayed the onset of BS infection, indicating that both regimens induced cross-stage immunity. Moreover, both CQ- and AS-ITV induced CD8(+) T cells in the liver that eliminated malaria-infected hepatocytes in vitro, as well as Abs that recognized pre-erythrocytic parasites. Sera from both groups of mice inhibited spz invasion of hepatocytes in vitro, but only CQ-ITV induced high levels of anti-BS Abs. Finally, passive transfer of sera from CQ-ITV-treated mice delayed the onset of erythrocytic infection in the majority of mice challenged with P. yoelii iRBCs. Besides constituting the first characterization, to our knowledge, of AS-ITV as a vaccination strategy, our data show that ITV strategies that lead to subtle differences in the persistence of parasites in the blood enable the characterization of the resulting immune responses, which will contribute to future research in vaccine design and malaria interventions.


Assuntos
Artemisininas/administração & dosagem , Cloroquina/administração & dosagem , Eritrócitos/imunologia , Eritrócitos/parasitologia , Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/imunologia , Malária/imunologia , Plasmodium yoelii/imunologia , Animais , Anopheles/imunologia , Anticorpos Antiprotozoários/biossíntese , Anticorpos Antiprotozoários/sangue , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Artemisia/imunologia , Artemisininas/uso terapêutico , Artesunato , Cloroquina/uso terapêutico , Eritrócitos/efeitos dos fármacos , Feminino , Malária/sangue , Malária/prevenção & controle , Vacinas Antimaláricas/sangue , Camundongos , Camundongos Endogâmicos BALB C , Fitoterapia/métodos , Plasmodium yoelii/efeitos dos fármacos , Esporozoítos/efeitos dos fármacos , Esporozoítos/imunologia , Esporozoítos/transplante , Fatores de Tempo , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/uso terapêutico
12.
PLoS Pathog ; 9(6): e1003420, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23853575

RESUMO

Glycan masking is an emerging vaccine design strategy to focus antibody responses to specific epitopes, but it has mostly been evaluated on the already heavily glycosylated HIV gp120 envelope glycoprotein. Here this approach was used to investigate the binding interaction of Plasmodium vivax Duffy Binding Protein (PvDBP) and the Duffy Antigen Receptor for Chemokines (DARC) and to evaluate if glycan-masked PvDBPII immunogens would focus the antibody response on key interaction surfaces. Four variants of PVDBPII were generated and probed for function and immunogenicity. Whereas two PvDBPII glycosylation variants with increased glycan surface coverage distant from predicted interaction sites had equivalent binding activity to wild-type protein, one of them elicited slightly better DARC-binding-inhibitory activity than wild-type immunogen. Conversely, the addition of an N-glycosylation site adjacent to a predicted PvDBP interaction site both abolished its interaction with DARC and resulted in weaker inhibitory antibody responses. PvDBP is composed of three subdomains and is thought to function as a dimer; a meta-analysis of published PvDBP mutants and the new DBPII glycosylation variants indicates that critical DARC binding residues are concentrated at the dimer interface and along a relatively flat surface spanning portions of two subdomains. Our findings suggest that DARC-binding-inhibitory antibody epitope(s) lie close to the predicted DARC interaction site, and that addition of N-glycan sites distant from this site may augment inhibitory antibodies. Thus, glycan resurfacing is an attractive and feasible tool to investigate protein structure-function, and glycan-masked PvDBPII immunogens might contribute to P. vivax vaccine development.


Assuntos
Antígenos de Protozoários/imunologia , Vacinas Antimaláricas/imunologia , Plasmodium vivax/imunologia , Proteínas de Protozoários/imunologia , Receptores de Superfície Celular/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/genética , Células COS , Chlorocebus aethiops , Sistema do Grupo Sanguíneo Duffy/genética , Sistema do Grupo Sanguíneo Duffy/imunologia , Glicosilação , Vacinas Antimaláricas/genética , Camundongos , Plasmodium vivax/genética , Ligação Proteica , Proteínas de Protozoários/genética , Ratos , Receptores de Superfície Celular/genética
13.
J Neurochem ; 129(5): 816-26, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24528233

RESUMO

Ischaemic strokes evoke blood-brain barrier (BBB) disruption and oedema formation through a series of mechanisms involving Rho-kinase activation. Using an animal model of human focal cerebral ischaemia, this study assessed and confirmed the therapeutic potential of Rho-kinase inhibition during the acute phase of stroke by displaying significantly improved functional outcome and reduced cerebral lesion and oedema volumes in fasudil- versus vehicle-treated animals. Analyses of ipsilateral and contralateral brain samples obtained from mice treated with vehicle or fasudil at the onset of reperfusion plus 4 h post-ischaemia or 4 h post-ischaemia alone revealed these benefits to be independent of changes in the activity and expressions of oxidative stress- and tight junction-related parameters. However, closer scrutiny of the same parameters in brain microvascular endothelial cells subjected to oxygen-glucose deprivation ± reperfusion revealed marked increases in prooxidant NADPH oxidase enzyme activity, superoxide anion release and in expressions of antioxidant enzyme catalase and tight junction protein claudin-5. Cotreatment of cells with Y-27632 prevented all of these changes and protected in vitro barrier integrity and function. These findings suggest that inhibition of Rho-kinase after acute ischaemic attacks improves cerebral integrity and function through regulation of endothelial cell oxidative stress and reorganization of intercellular junctions. Inhibition of Rho-kinase (ROCK) activity in a mouse model of human ischaemic stroke significantly improved functional outcome while reducing cerebral lesion and oedema volumes compared to vehicle-treated counterparts. Studies conducted with brain microvascular endothelial cells exposed to OGD ± R in the presence of Y-27632 revealed restoration of intercellular junctions and suppression of prooxidant NADPH oxidase activity as important factors in ROCK inhibition-mediated BBB protection.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/patologia , Isquemia Encefálica/prevenção & controle , Células Endoteliais/patologia , Estresse Oxidativo/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Junções Íntimas/patologia , Quinases Associadas a rho/antagonistas & inibidores , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/antagonistas & inibidores , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Amidas/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Western Blotting , Química Encefálica/efeitos dos fármacos , Células Cultivadas , Infarto Cerebral/patologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Lateralidade Funcional/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidases/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Desempenho Psicomotor/efeitos dos fármacos , Desempenho Psicomotor/fisiologia , Piridinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Junções Íntimas/efeitos dos fármacos
14.
BMC Neurosci ; 15: 131, 2014 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-25471043

RESUMO

BACKGROUND: Progesterone is neuroprotective in numerous preclinical CNS injury models including cerebral ischaemia. The aim of this study was two-fold; firstly, we aimed to determine whether progesterone delivery via osmotic mini-pump would confer neuroprotective effects and whether such neuroprotection could be produced in co-morbid animals. RESULTS: Animals underwent transient middle cerebral artery occlusion. At the onset of reperfusion, mice were injected intraperitoneally with progesterone (8 mg/kg in dimethylsulfoxide). Adult and aged C57 Bl/6 mice were dosed additionally with subcutaneous infusion (1.0 µl/h of a 50 mg/ml progesterone solution) via implanted osmotic minipumps. Mice were allowed to survive for up to 7 days post-ischaemia and assessed for general well-being (mass loss and survival), neurological score, foot fault and t-maze performance. Progesterone reduced neurological deficit [F(1,2) = 5.38, P = 0.027] and number of contralateral foot-faults [F(1,2) = 7.36, P = 0.0108] in adult, but not aged animals, following ischaemia. In hypertensive animals, progesterone treatment lowered neurological deficit [F(1,6) = 18.31, P = 0.0001], reduced contralateral/ipsilateral alternation ratio % [F(1,2) = 17.05, P = 0.0006] and time taken to complete trials [F(1,2) = 15.92, P = 0.0009] for t-maze. CONCLUSION: Post-ischemic progesterone administration via mini-pump delivery is effective in conferring functional improvement in a transient MCAO model in adult mice. Preliminary data suggests such a treatment regimen was not effective in producing a protective effect in aged mice. However, in hypertensive mice, who received post-ischemic progesterone intraperitoneally at the onset of reperfusion had better functional outcomes than control hypertensive mice.


Assuntos
Encéfalo/efeitos dos fármacos , Ataque Isquêmico Transitório/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Progesterona/administração & dosagem , Fatores Etários , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Hipertensão/fisiopatologia , Infarto da Artéria Cerebral Média , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Recuperação de Função Fisiológica/efeitos dos fármacos , Índice de Gravidade de Doença , Análise de Sobrevida
15.
Infect Immun ; 81(11): 4171-81, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23980113

RESUMO

Vaccination with a single dose of genetically attenuated malaria parasites can induce sterile protection against sporozoite challenge in the rodent Plasmodium yoelii model. Protection is dependent on CD8(+) T cells, involves perforin and gamma interferon (IFN-γ), and is correlated with the expansion of effector memory CD8(+) T cells in the liver. Here, we have further characterized vaccine-induced changes in the CD8(+) T cell phenotype and demonstrated significant upregulation of CD11c on CD3(+) CD8b(+) T cells in the liver, spleen, and peripheral blood. CD11c(+) CD8(+) T cells are predominantly CD11a(hi) CD44(hi) CD62L(-), indicative of antigen-experienced effector cells. Following in vitro restimulation with malaria-infected hepatocytes, CD11c(+) CD8(+) T cells expressed inflammatory cytokines and cytotoxicity markers, including IFN-γ, tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2), perforin, and CD107a. CD11c(-) CD8(+) T cells, on the other hand, expressed negligible amounts of all inflammatory cytokines and cytotoxicity markers tested, indicating that CD11c marks multifunctional effector CD8(+) T cells. Coculture of CD11c(+), but not CD11c(-), CD8(+) T cells with sporozoite-infected primary hepatocytes significantly inhibited liver-stage parasite development. Tetramer staining for the immunodominant circumsporozoite protein (CSP)-specific CD8(+) T cell epitope demonstrated that approximately two-thirds of CSP-specific cells expressed CD11c at the peak of the CD11c(+) CD8(+) T cell response, but CD11c expression was lost as the CD8(+) T cells entered the memory phase. Further analyses showed that CD11c(+) CD8(+) T cells are primarily KLRG1(+) CD127(-) terminal effectors, whereas all KLRG1(-) CD127(+) memory precursor effector cells are CD11c(-) CD8(+) T cells. Together, these results suggest that CD11c marks a subset of highly inflammatory, short-lived, antigen-specific effector cells, which may play an important role in eliminating infected hepatocytes.


Assuntos
Antígeno CD11c/biossíntese , Linfócitos T CD8-Positivos/imunologia , Vacinas Antimaláricas/imunologia , Plasmodium yoelii/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Sangue/imunologia , Linfócitos T CD8-Positivos/química , Feminino , Imunofenotipagem , Fígado/imunologia , Vacinas Antimaláricas/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Baço/imunologia , Subpopulações de Linfócitos T/química , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
16.
Anim Cogn ; 16(2): 177-86, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22976576

RESUMO

The learning abilities of planarian worms (Dugesia tigrina) were assessed by using a number of Pavlovian conditioning paradigms. Experiment 1 showed that planaria were susceptible to basic conditioning in that they readily developed a conditioned response to a change in ambient luminance when it was consistently paired with an electric shock over a number of trials. In Experiment 2, the change in luminance was presented in a compound with a vibration stimulus during conditioning. Subsequent tests revealed poor conditioning of the elements compared with control groups in which the animals were conditioned in the presence of the elements alone, an instance of overshadowing. In Experiment 3, pre-training of one of the elements before compound conditioning resulted in blocking of learning about the other element. These results add to other studies that have reported cue competition effects in animal species belonging to different phyla (chordate, mollusk, arthropod), suggesting that learning in these phyla could be ruled by similar principles. The results are discussed adopting an evolutionary-comparative approach.


Assuntos
Condicionamento Clássico , Sinais (Psicologia) , Planárias , Animais , Eletrochoque , Estimulação Luminosa
17.
Front Microbiol ; 14: 1155956, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37228381

RESUMO

Microbial community composition has increasingly emerged as a key determinant of antibiotic resistance gene (ARG) content. However, in activated sludge wastewater treatment plants (AS-WWTPs), a comprehensive understanding of the microbial community assembly process and its impact on the persistence of antimicrobial resistance (AMR) remains elusive. An important part of this process is the immigration dynamics (or community coalescence) between the influent and activated sludge. While the influent wastewater contains a plethora of ARGs, the persistence of a given ARG depends initially on the immigration success of the carrying population, and the possible horizontal transfer to indigenously resident populations of the WWTP. The current study utilized controlled manipulative experiments that decoupled the influent wastewater composition from the influent microbial populations to reveal the fundamental mechanisms involved in ARG immigration between sewers and AS-WWTP. A novel multiplexed amplicon sequencing approach was used to track different ARG sequence variants across the immigration interface, and droplet digital PCR was used to quantify the impact of immigration on the abundance of the targeted ARGs. Immigration caused an increase in the abundance of over 70 % of the quantified ARGs. However, monitoring of ARG amplicon sequence variants (ARG-ASVs) at the immigration interface revealed various immigration patterns such as (i) suppression of the indigenous mixed liquor ARG-ASV by the immigrant, or conversely (ii) complete immigration failure of the influent ARG-ASV. These immigration profiles are reported for the first time here and highlight the crucial information that can be gained using our novel multiplex amplicon sequencing techniques. Future studies aiming to reduce AMR in WWTPs should consider the impact of influent immigration in process optimisation and design.

18.
J Psychopharmacol ; 37(5): 484-489, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36633290

RESUMO

BACKGROUND: Cannabis use suppresses the endocannabinoid system in healthy individuals. However, the association between cannabis use with the endocannabinoid system is understudied in individuals with psychosis despite the high rate of cannabis use in these individuals. METHODS: We enrolled 83 individuals who were admitted to an inpatient psychiatric unit with psychotic presentations, and measured their plasma levels of main endocannabinoids, Anandamide (AEA) and 2-Acylglycerol (2-AG), and endocannabinoid related compounds, Palmitoylethanolamine, and N-oleoylethanolamine. Cannabis use was assessed with urine toxicology and frequency of cannabis use was assessed using self-reported questionnaires. The Positive and Negative Syndrome Scale was used to assess the severity of psychotic symptoms. RESULTS: Overall, we had 38 individuals in cannabis positive group (CN+) and 45 individuals in cannabis negative group (CN-). Compared to CN-, CN+ group had lower plasma levels of AEA, which remained significant after controlling for age, gender, race/ethnicity, and use of other drugs. CONCLUSION: Cannabis use is associated with low plasma AEA levels in individuals with psychosis, which is in the same line with reported suppressive effects of cannabis on the endocannabinoid system in healthy individuals. Further studies are needed to investigate the clinical significance of this finding.


Assuntos
Cannabis , Alucinógenos , Transtornos Psicóticos , Humanos , Endocanabinoides , Agonistas de Receptores de Canabinoides , Alcamidas Poli-Insaturadas , Transtornos Psicóticos/tratamento farmacológico
19.
Cereb Circ Cogn Behav ; 5: 100189, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37941765

RESUMO

Although dementia research has been dominated by Alzheimer's disease (AD), most dementia in older people is now recognised to be due to mixed pathologies, usually combining vascular and AD brain pathology. Vascular cognitive impairment (VCI), which encompasses vascular dementia (VaD) is the second most common type of dementia. Models of VCI have been delayed by limited understanding of the underlying aetiology and pathogenesis. This review by a multidisciplinary, diverse (in terms of sex, geography and career stage), cross-institute team provides a perspective on limitations to current VCI models and recommendations for improving translation and reproducibility. We discuss reproducibility, clinical features of VCI and corresponding assessments in models, human pathology, bioinformatics approaches, and data sharing. We offer recommendations for future research, particularly focusing on small vessel disease as a main underpinning disorder.

20.
J Neurochem ; 123 Suppl 2: 52-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23050642

RESUMO

As a predictor of potential clinical outcome, we performed a systematic review of controlled studies that assessed experimental stroke outcome in rodents maintained on special diets (calorie restriction and ketogenic diet) or following the direct administration of ketone bodies. Pre-clinical studies were identified by searching web databases and the reference lists of relevant original articles and reviews. Sixteen published studies (a total of 733 experimental animals) met specific criteria and were analyzed using Cochrane Review Manager software. This resulted in objective evidence to suggest beneficial effects of the ketogenic pathway on pathological and functional outcomes following experimental stroke.


Assuntos
Dieta Cetogênica/métodos , Modelos Animais de Doenças , Corpos Cetônicos/administração & dosagem , Acidente Vascular Cerebral/dietoterapia , Acidente Vascular Cerebral/prevenção & controle , Animais , Bases de Dados Factuais/estatística & dados numéricos , Humanos
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