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1.
Curr Cardiol Rep ; 23(8): 104, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34196800

RESUMO

PURPOSE OF REVIEW: Obesity is associated with an increased risk for type 2 diabetes, and weight loss in adults with obesity and type 2 diabetes may be indicated to reduce health risk and improve diabetes control. It is important to understand the effectiveness of weight loss interventions for the prevention and treatment of type 2 diabetes. RECENT FINDINGS: Lifestyle interventions for weight loss show effectiveness for prevention of type 2 diabetes. Weight loss in patients with type 2 diabetes can decrease cardiometabolic risk and improve diabetes control. However, diabetes remission with lifestyle approaches is limited and to achieve this medical approaches such as bariatric surgery that result in greater magnitudes of weight loss may be necessary. Dissemination of lifestyle interventions for weight loss, along with other medical approaches such as bariatric surgery when indicated, are needed to reduce the health burden of type 2 diabetes in patients with obesity.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Adulto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Humanos , Estilo de Vida , Obesidade/complicações , Obesidade/terapia , Redução de Peso
2.
Eur J Immunol ; 48(7): 1153-1163, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29569714

RESUMO

In this study, recombinant pox viral vaccination was shown to induce highly elevated IgG2a and low IgG1 antibody expression in mice lacking IL-4 or STAT6, whilst IL-13-/- mice exhibited elevated IgG1, but very low IgG2a. These findings revealed that IL-13 and IL-4 differentially regulated antibody development. To understand this further, when STAT6-/- mice were given a vaccine co-expressing IL-13Rα2 that temporarily sequestered IL-13, significantly reduced IgG2a expression, was detected. These findings for the first time demonstrated that IL-13 regulated IgG2a differentiation utilising an alternative IL-13R signalling pathway independent of STAT6 (IL-13Rα2 pathway). This was further corroborated by the (i) elevated IL-13Rα2 expression detected on STAT6-/- lung MHCII+ CD11c+ cells 24 h post IL-13 inhibitor vaccination and ii) significant up-regulation of IL-13Rα2 expression on spleen and lung derived MHCII+ CD11c+ following inhibition of STAT6 signalling in vitro, or vaccination with IL-4R/STAT6 antagonist in vivo. When T follicular helper (Tfh) cells which regulate antibody differentiation were assessed post vaccination, although no difference in IL-4 expression was observed, greatly reduced IFN-γ expression was detected in IL-13-/- and STAT6-/- mice compared to wild-type. These findings support the notion that the balance of IL-13 level at the vaccination site can differentially regulate T and B-cell immune outcomes.


Assuntos
Avipoxvirus/fisiologia , Subunidade alfa2 de Receptor de Interleucina-13/imunologia , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Infecções por Poxviridae/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/metabolismo , Células Cultivadas , Switching de Imunoglobulina , Imunoglobulina G/metabolismo , Isotipos de Imunoglobulinas/metabolismo , Interleucina-13/genética , Subunidade alfa2 de Receptor de Interleucina-13/genética , Interleucina-4/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo , Transdução de Sinais , Vacinas Virais/genética
3.
J Gen Virol ; 98(10): 2556-2568, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28933686

RESUMO

To establish the importance of virus-heparan sulfate (HS) interactions in virus infectivity, the poxvirus vaccinia virus (VACV) was used, as it binds HS and has both enveloped virus (EV) and non-enveloped mature virus (MV) forms. Initial studies showed that heparin inhibited plaque formation by both MV-rich WR and EV-rich IHD-J strains of VACV, with the EV-rich strain also losing trademark 'comet'-shaped plaques. However, using GFP-tagged EV and MV forms of VACV, based on IC50 values, heparin was 16-fold more effective at inhibiting the infectivity of the EV form compared to the MV form. Furthermore, 6-O and N-sulfation of the glucosamine residues of heparin was essential for inhibition of the infectivity of both VACV forms. Several low-molecular-weight HS mimetics were also shown to have substantial antiviral activity, with glycosidic linkages, chain length and monosaccharide backbone being important contributors towards anti-VACV activity. In fact, the d-mannose-based sulfated oligosaccharide mixture, PI-88 (Muparfostat), was four-fold more active than heparin at inhibiting MV infections. Paradoxically, despite heparin and HS mimetics being potent inhibitors of VACV infections, removal of HS from cell surfaces by enzymatic or genetic means resulted in only a modest reduction in infectivity. It is unlikely that this paradox can be explained by steric hindrance, due to the low molecular weight of the HS mimetics (~1-2.5 kDa), with a more likely explanation being that binding of heparin/HS mimetics to free VACV initiates an abortive viral infection. Based on this explanation, HS mimetics have considerable potential as antivirals against HS-binding viruses.

4.
J Gen Virol ; 98(3): 496-505, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28056224

RESUMO

We have previously established that mucosal uptake of recombinant fowlpox virus (rFPV) vaccines is far superior to other vector-based vaccines. Specifically, intranasal priming with rFPV vaccines can recruit unique antigen-presenting cells, which induce excellent mucosal and systemic HIV-specific CD8+ T-cell immunity. In this study, we have for the first time investigated the in vivo dissemination, safety and expression kinetics of rFPV post intranasal delivery using recombinant viruses expressing green fluorescent protein or mCherry. Both confocal microscopy of tissue sections using green fluorescent protein and in vivo Imaging System (IVIS) spectrum live animal and whole organ imaging studies using mCherry revealed that (i) the peak antigen expression occurs 12 to 24 h post vaccination and no active viral gene expression is detected 96 h post vaccination. (ii) The virus only infects the initial vaccination site (lung and nasal cavity) and does not disseminate to distal sites such as the spleen or gut. (iii) More importantly, rFPV does not cross the olfactory receptor neuron pathway. Collectively, our findings indicate that rFPV vector-based vaccines have all the hallmarks of a safe and effective mucosal delivery vector, suitable for clinical evaluation.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/efeitos adversos , Vírus da Varíola das Aves Domésticas , Antígenos HIV/administração & dosagem , Antígenos HIV/efeitos adversos , Vacinas Sintéticas/efeitos adversos , Vacinas contra a AIDS/metabolismo , Administração Intranasal , Animais , Trato Gastrointestinal/metabolismo , Vetores Genéticos/administração & dosagem , Vetores Genéticos/efeitos adversos , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Antígenos HIV/metabolismo , Proteínas Luminescentes/análise , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Imagem Molecular , Mucosa Nasal/metabolismo , Baço/metabolismo , Vacinação , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/metabolismo , Proteína Vermelha Fluorescente
5.
N C Med J ; 77(4): 293-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27422958

RESUMO

The US Department of Health and Human Services and the Centers for Medicare & Medicaid Services have announced goals and timelines to transition from payments based on volume to payments based on value, quality, and efficient delivery of care. These value-based payments and alternative payment models will impact all health care professionals and provider organizations by encouraging better care, healthier people, and spending health care dollars wisely and efficiently.


Assuntos
Centers for Medicare and Medicaid Services, U.S./economia , Aquisição Baseada em Valor , Reforma dos Serviços de Saúde , Política de Saúde , Humanos , North Carolina , Objetivos Organizacionais , Qualidade da Assistência à Saúde , Estados Unidos
6.
J Surg Res ; 196(2): 368-72, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25881790

RESUMO

BACKGROUND: Coagulopathy after injury contributes to hemorrhage and death. Treatment with specific coagulation factors could decrease hemorrhage and mortality. Our aim was to compare fibrinogen and prothrombin complex concentrate (PCC) in a rabbit model of hemorrhagic shock. MATERIALS AND METHODS: New Zealand white rabbits were anesthetized. Blood was withdrawn to a mean arterial pressure (MAP) of 30-40 mm Hg for 30 min. Animals were resuscitated with lactated Ringer to a MAP of 50-60 mm Hg and randomized to receive 100 mg/kg of fibrinogen, PCC 25 IU/kg, or lactated Ringer. A liver injury was created. A MAP of 50-60 mm Hg was maintained for 60 min. The primary outcome was blood loss, and secondary outcomes were fluid administered and coagulopathy as measured by plasma-based tests. RESULTS: There were eight animals in each group. Median blood loss was significantly higher in the fibrinogen group, at 122 mL (95% confidence interval [CI], 75-194), when compared with that in the control group, 35 mL (95% CI, 23-46; P value = 0.001), and the PCC group, 26 mL (95% CI, 4-54; P value = 0.002). Resuscitation fluid requirement was highest in the fibrinogen group, at 374 mL (95% CI, 274-519), and lowest in the PCC group, at 238 mL (95% CI, 212-309) (P = 0.01). Plasma-based coagulation tests were not different among groups. CONCLUSIONS: In a rabbit model, PCC did not have a significant effect on blood loss. Fibrinogen increased blood loss and fluid requirements.


Assuntos
Transtornos da Coagulação Sanguínea/tratamento farmacológico , Fatores de Coagulação Sanguínea/uso terapêutico , Fibrinogênio/uso terapêutico , Fígado/lesões , Choque Hemorrágico/complicações , Animais , Transtornos da Coagulação Sanguínea/etiologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Hidratação , Coelhos , Distribuição Aleatória , Choque Hemorrágico/terapia
7.
J Biol Chem ; 288(27): 19760-72, 2013 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-23689510

RESUMO

Glucose-dependent insulinotropic polypeptide (GIP) is an endogenous hormonal factor (incretin) that, upon binding to its receptor (GIPr; a class B G-protein-coupled receptor), stimulates insulin secretion by beta cells in the pancreas. There has been a lack of potent inhibitors of the GIPr with prolonged in vivo exposure to support studies on GIP biology. Here we describe the generation of an antagonizing antibody to the GIPr, using phage and ribosome display libraries. Gipg013 is a specific competitive antagonist with equally high potencies to mouse, rat, dog, and human GIP receptors with a Ki of 7 nm for the human GIPr. Gipg013 antagonizes the GIP receptor and inhibits GIP-induced insulin secretion in vitro and in vivo. A crystal structure of Gipg013 Fab in complex with the human GIPr extracellular domain (ECD) shows that the antibody binds through a series of hydrogen bonds from the complementarity-determining regions of Gipg013 Fab to the N-terminal α-helix of GIPr ECD as well as to residues around its highly conserved glucagon receptor subfamily recognition fold. The antibody epitope overlaps with the GIP binding site on the GIPr ECD, ensuring competitive antagonism of the receptor. This well characterized antagonizing antibody to the GIPr will be useful as a tool to further understand the biological roles of GIP.


Assuntos
Anticorpos Monoclonais Murinos , Epitopos , Fragmentos Fab das Imunoglobulinas , Receptores dos Hormônios Gastrointestinais , Animais , Anticorpos Monoclonais Murinos/química , Anticorpos Monoclonais Murinos/genética , Anticorpos Monoclonais Murinos/metabolismo , Anticorpos Monoclonais Murinos/farmacologia , Cristalografia por Raios X , Cães , Epitopos/química , Epitopos/genética , Epitopos/metabolismo , Polipeptídeo Inibidor Gástrico , Células HEK293 , Humanos , Ligação de Hidrogênio , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/metabolismo , Fragmentos Fab das Imunoglobulinas/farmacologia , Insulina/genética , Insulina/metabolismo , Secreção de Insulina , Masculino , Camundongos , Ligação Proteica , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Ratos , Ratos Sprague-Dawley , Receptores dos Hormônios Gastrointestinais/antagonistas & inibidores , Receptores dos Hormônios Gastrointestinais/química , Receptores dos Hormônios Gastrointestinais/genética , Receptores dos Hormônios Gastrointestinais/metabolismo , Relação Estrutura-Atividade
8.
Obesity (Silver Spring) ; 32(1): 23-31, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37789600

RESUMO

OBJECTIVE: This study examined the prevalence of ≥150 min/wk of moderate-to-vigorous physical activity (MVPA) using different criteria for bout length and to examine associations with measures of obesity, cardiorespiratory fitness, and cardiometabolic risk factors in healthy adults with overweight or obesity. METHODS: Baseline data from healthy adults (N = 375; age [mean ± SD] = 45.2 ± 7.7 years; BMI = 32.3 ± 3.8 kg/m2 ) enrolled in a behavioral weight-loss intervention were examined cross-sectionally. Categorization was by objectively measured MVPA as follows: 1) LOW-MVPA: <150 min/wk (n = 122, 32.5%); 2) MVPA-NON-BOUTED: ≥150 min/wk in bouts < 10 min (n = 72, 19.2%); 3) MVPA-COMBINED: ≥150 min/wk with a combination of bouts < 10 and ≥10 min (n = 50, 13.3%); and 4) MVPA-BOUTED: ≥150 min/wk with bouts ≥ 10 min (n = 131, 34.9%). RESULTS: Weight, BMI, and waist circumference were higher in the LOW-MVPA category versus the other categories. Body fatness was significantly lower in the MVPA-BOUTED category compared with the LOW-MVPA category (p < 0.05). Differences by category for cardiorespiratory fitness and cardiometabolic risk factors were limited. CONCLUSIONS: Some adults with overweight or obesity may be more active than they perceived themselves to be, and accumulation of ≥150 min/wk of MVPA may have favorable effects on weight and adiposity status. Findings may influence physical activity recommendations, and confirmation with prospective and randomized studies is needed.


Assuntos
Fatores de Risco Cardiometabólico , Sobrepeso , Adulto , Humanos , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Estudos Prospectivos , Obesidade/epidemiologia , Exercício Físico , Fatores de Risco
9.
Physiol Rep ; 11(24): e15894, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38110700

RESUMO

The acute reduction in peripheral arterial stiffness during reactive hyperemia is assumed to be flow-mediated; however, the mechanism remains unproven. We hypothesized that restricting the blood flow increase during reactive hyperemia would abolish the reduction in peripheral arterial stiffness. Fourteen healthy young adults (5 females, 25 ± 5 years, mean ± SD) underwent reactive hyperemia with a rapid-release cuff on the upper arm inflated to 220 mmHg for 5 min: once with unrestricted blood flow and once with restricted blood flow by manually applying pressure to the brachial artery. Brachial-radial pulse wave velocity (PWV) was measured with tonometers over brachial and radial arteries before cuff inflation and at 5, 15, and 30 min after release. Brachial blood flow was monitored with Doppler ultrasound. Baseline brachial-radial PWV was similar between conditions (10.3 ± 1.8 vs. 10.7 ± 1.7 m/s). With unrestricted flow, PWV decreased 5 min post-reactive hyperemia (8.6 ± 1.1 m/s; p < 0.05) and returned near baseline at 15 and 30 min post (p < 0.05). With restricted flow, PWV did not change (p > 0.05) post-reactive hyperemia. Reactive hyperemia acutely reduced peripheral arterial stiffness, but not when brachial artery blood flow increase was restricted. This suggests that the reduction in peripheral arterial stiffness during reactive hyperemia depends on increased blood flow.


Assuntos
Hiperemia , Rigidez Vascular , Feminino , Adulto Jovem , Humanos , Análise de Onda de Pulso , Artéria Braquial/fisiologia , Artéria Radial , Pressão Sanguínea , Velocidade do Fluxo Sanguíneo/fisiologia
10.
Immunol Cell Biol ; 89(3): 367-74, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20956986

RESUMO

Numerous human immunodeficiency virus (HIV)-1 vaccines have been developed over the last three decades, but to date an effective HIV-1 vaccine that can be used for prophylactic or therapeutic purposes in humans has not been identified. The failures and limited successes of HIV-1 vaccines have highlighted the gaps in our knowledge with regard to fundamental immunity against HIV-1 and have provided insights for vaccine strategies that may be implemented for designing more effective HIV-1 vaccines in the future. Recent studies have shown that robust mucosal immunity, high avidity and polyfunctional T cells, and broadly neutralizing antibodies are important factors governing the induction of protective immunity against HIV-1. Furthermore, optimization of vaccine delivery methods for DNA or live viral vector-based vaccines, elucidating the immune responses of individuals who remain resistant to HIV-1 infections and also understanding the core immune responses mediating protection against simian immunodeficiency viruses (SIV) and HIV-1 in animal models following vaccination, are key aspects to be regarded for designing more effective HIV-1 vaccines in the future.


Assuntos
Vacinas contra a AIDS/imunologia , HIV-1/imunologia , Imunidade Adaptativa/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Vetores Genéticos/metabolismo , HIV-1/genética , Humanos , Imunidade nas Mucosas/imunologia , Vacinas contra a SAIDS/imunologia , Linfócitos T/imunologia , Vacinas Atenuadas/imunologia
11.
J Immunol ; 183(5): 3324-31, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19657092

RESUMO

A strong cell-mediated immune response is critical for controlling viral infections and is regulated by a number of cytokines, including IL-12 and IL-18. Indeed, some viruses have evolved to specifically target these pathways to counter the host immune response. Orthopoxviruses, including ectromelia virus, encode immune evasion molecules that specifically target IL-18 and IFN-gamma. We hypothesized that IL-12 and IL-18 are pivotal for induction of IFN-gamma production and subsequent generation of an effective host response to ectromelia virus infection. In this study, we demonstrate that absence of both IL-12p40 and IL-18 resulted in increased susceptibility to infection that was associated with skewing of the cytokine response to Th2 and a reduction in NK and CTL responses. The decrease in CTL response correlated with a defect in CD8(+) T cell proliferation and lower numbers of virus-specific CD8(+) T cells. Lack of either IL-12p40 and/or IL-18 was also associated with reduced numbers of CD8(+) T cells at sites of infection and with an increase in the numbers of splenic T regulatory cells. Taken together, our data indicate that IL-12p40 and IL-18 act in concert and play an important antiviral role through the up-regulation of IFN-gamma production and cell-mediated immune responses.


Assuntos
Vírus da Ectromelia/imunologia , Ectromelia Infecciosa/imunologia , Subunidade p40 da Interleucina-12/fisiologia , Interleucina-18/fisiologia , Animais , Células Cultivadas , Citotoxicidade Imunológica/genética , Ectromelia Infecciosa/genética , Ectromelia Infecciosa/mortalidade , Predisposição Genética para Doença/genética , Imunidade Celular/genética , Imunidade Inata/genética , Subunidade p40 da Interleucina-12/antagonistas & inibidores , Subunidade p40 da Interleucina-12/deficiência , Subunidade p40 da Interleucina-12/genética , Interleucina-18/deficiência , Interleucina-18/genética , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/patologia , Células Th2/imunologia , Células Th2/metabolismo , Células Th2/patologia
12.
Noise Health ; 12(48): 159-65, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20603572

RESUMO

The efficacy of three different doses of sodium salicylate (SAL) in combination with one dose of N-acetylcysteine (NAC) to prevent noise-induced hearing loss was studied in chinchillas. After obtaining baseline-hearing thresholds, the chinchillas were randomly assigned to one of four treatment groups: three sets were injected intraperitoneally with 325 mg/kg NAC combined with 25, 50, or 75 mg/kg SAL, and a separate control group was injected with an equal volume of saline. Animals were injected twice daily for 2 days prior to and 1 hour before the noise exposure (6 hours to a 105-dB Standard Pressure Level octave band noise centered at 4 kHz). Immediate post-noise hearing thresholds were obtained followed by post-noise treatments at 1 hour then twice-daily for 2 days. Hearing tests continued at 1, 2, and 3 weeks post-noise, and immediately after the last hearing test, animals' cochleae were stained for hair cell counts. All the groups showed hearing improvement until week 2. However, at week 3, saline treated animals demonstrated a 17-33 dB SPL permanent threshold shift (PTS) across the test frequencies. Hearing loss was lowest in the 50 SAL/325 NAC mg/kg group (all frequencies, P < 0.001), and although PTS was reduced in the 25 and 75 mg/kg SAL dosage groups compared to the saline group, only the 75 mg/kg SAL group was significantly different at all but 2 kHz frequency. Coupled with the hearing loss, outer hair cell (OHC) loss was maximal in the 4-8 kHz cochlear region of saline treated animals. However, there was a substantial reduction in the mean OHC loss of the NAC plus 50 or 75 mg/kg (but not the 25 mg/kg) SAL groups. These findings suggest that SAL in combination with NAC is effective in reducing noise damage to the cochlea, but SAL has a relatively narrow therapeutic dosing window.


Assuntos
Acetilcisteína/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Sequestradores de Radicais Livres/administração & dosagem , Perda Auditiva Provocada por Ruído/prevenção & controle , Salicilato de Sódio/administração & dosagem , Acetilcisteína/farmacologia , Análise de Variância , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Limiar Auditivo/efeitos dos fármacos , Chinchila , Modelos Animais de Doenças , Esquema de Medicação , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Feminino , Sequestradores de Radicais Livres/farmacologia , Células Ciliadas Auditivas Externas/efeitos dos fármacos , Células Ciliadas Auditivas Externas/patologia , Perda Auditiva Provocada por Ruído/diagnóstico , Testes Auditivos , Injeções Intraperitoneais , Distribuição Aleatória , Salicilato de Sódio/farmacologia , Espectrografia do Som
13.
Endocrinol Metab Clin North Am ; 49(2): 289-301, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32418591

RESUMO

Physical activity contributes to body weight regulation. At least 150 minutes per week of moderate-to-vigorous intensity physical activity may be needed. When not coupled with dietary restriction, physical activity contributes to an average weight loss of approximately 2 to 3 kg in interventions up to 6 months in duration; when added to modest dietary restriction it adds 20% additional weight loss compared with modest dietary restriction alone. Physical activity is associated with enhanced long-term weight loss and attenuation of weight regain and should be included within clinical and public health approaches to prevent weight regain and to treat obesity.


Assuntos
Terapia por Exercício , Exercício Físico , Obesidade/terapia , Dispositivos Eletrônicos Vestíveis , Terapia por Exercício/instrumentação , Terapia por Exercício/métodos , Humanos , Obesidade/dietoterapia , Obesidade/prevenção & controle
14.
Sci Rep ; 9(1): 5661, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30952887

RESUMO

A HIV vaccine that provides mucosal immunity is urgently needed. We evaluated an intranasal recombinant Fowlpox virus (rFPV) priming vaccine followed by intramuscular Modified Vaccinia Ankara (rMVA) booster vaccine, both expressing SIV antigens. The vaccination generated mucosal and systemic SIV-specific CD4+ T cell mediated immunity and was associated with partial protection against high-dose intrarectal SIVmac251 challenge in outbred pigtail macaques. Three of 12 vaccinees were completely protected and these animals elicited sustained Gag-specific poly-functional, cytotoxic mucosal CD4+ T cells, complemented by systemic poly-functional CD4+ and CD8+ T cell immunity. Humoral immune responses, albeit absent in completely protected macaques, were associated with partial control of viremia in animals with relatively weaker mucosal/systemic T cell responses. Co-expression of an IL-4R antagonist by the rFPV vaccine further enhanced the breadth and cytotoxicity/poly-functionality of mucosal vaccine-specific CD4+ T cells. Moreover, a single FPV-gag/pol/env prime was able to induce rapid anamnestic gp140 antibody response upon SIV encounter. Collectively, our data indicated that nasal vaccination was effective at inducing robust cervico-vaginal and rectal immunity, although cytotoxic CD4+ T cell mediated mucosal and systemic immunity correlated strongly with 'complete protection', the different degrees of protection observed was multi-factorial.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Vírus da Varíola das Aves Domésticas/imunologia , Macaca nemestrina/imunologia , Vacinas contra a SAIDS/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Vacinas Sintéticas/imunologia , Vacinas contra a AIDS/imunologia , Administração Intranasal/métodos , Animais , Linfócitos T CD8-Positivos/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunidade nas Mucosas/imunologia , Imunização Secundária/métodos , Memória Imunológica/imunologia , Injeções Intramusculares/métodos , Macaca nemestrina/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vacinação/métodos , Vacínia/imunologia , Vaccinia virus/imunologia
15.
Free Radic Biol Med ; 44(9): 1772-84, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18328271

RESUMO

Acute acoustic trauma (AAT) results in oxidative stress to the cochlea through overproduction of cellular reactive oxygen, nitrogen, and other free radical species appearing from 1 h to 10 days after noise exposure. It has been shown that N-acetyl-L-cysteine (NAC), a glutathione prodrug, and acetyl-L-carnitine (ALCAR), a mitochondrial biogenesis agent, are effective in reducing noise-induced hearing loss. Phenyl N-tert-butylnitrone (PBN), a nitrone-based free radical trap, appears to suppress oxidative stress in a variety of disorders and several biological models. In this study, we tested whether 4-hydroxy PBN (4-OHPBN), a major metabolite of PBN, administered 4 h after noise exposure is effective in treating noise-induced hearing loss and whether a combination of antioxidant drugs (4-OHPBN plus NAC and 4-OHPBN plus NAC plus ALCAR) provides greater efficacy in attenuating AAT since each agent addresses different injury mechanisms. Chinchilla were exposed to a 105 dB octave-band noise centered at 4 kHz for 6 h. 4-OHPBN and combinations of antioxidant drugs were intraperitoneally administered beginning 4 h after noise exposure. Hearing threshold shifts in auditory brainstem responses and missing outer hair cell counts were obtained. 4-OHPBN reduced threshold shifts in a dose-dependent manner while both drug combinations showed greater effects. These results demonstrate that 4-OHPBN and combinations of antioxidants can effectively treat acute acoustic trauma and drug combinations may increase the effectiveness of treatment and decrease the required individual medication dose.


Assuntos
Antioxidantes/metabolismo , Cóclea/lesões , Cóclea/metabolismo , Óxidos N-Cíclicos/farmacologia , Perda Auditiva Provocada por Ruído , Fármacos Neuroprotetores/farmacologia , Animais , Audiometria , Tronco Encefálico/embriologia , Chinchila , Feminino , Células Ciliadas Auditivas/metabolismo , Perda Auditiva , Modelos Biológicos , Ruído , Estresse Oxidativo
16.
J Am Acad Audiol ; 19(4): 325-36, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18795471

RESUMO

This study examined the association between ultrahigh-frequency (UHF) hearing sensitivity and distortion-product otoacoustic emission (DPOAE) levels at conventional frequencies. Behavioral thresholds were measured from 2 through 16 kHz, and DPOAE levels were measured at discrete f2 frequencies between 2 through 8 kHz in 553 young normal-hearing adult male participants. A DPOAE frequency sweep was measured with primary stimulus levels of L1/L2 = 65/55 dB SPL and an f2/f1 of 1.2. Significant negative correlations, although weak, were found between UHF behavioral thresholds and DPOAE levels. As UHF behavioral thresholds worsened, DPOAE levels decreased at all frequencies. When the data were categorized into two groups, "better" and "worse" UHF behavioral thresholds, significant differences were apparent between the two groups for DPOAEs. Additionally, those with better UHF thresholds had better conventional thresholds compared to those in the worse UHF threshold group. The results of this age-restricted, large-sample-size study confirm and augment findings from earlier studies demonstrating that UHF hearing sensitivity has some influence on DPOAE measures at frequencies from 2 through 8 kHz with moderate stimulus levels. However, because those with better UHF thresholds also had better conventional thresholds and the significant correlations found were weak, this work supports the importance of UHF hearing testing in conjunction with otoacoustic emission measures to identify basal cochlear insults not evident from behavioral testing at conventional frequencies.


Assuntos
Limiar Auditivo/fisiologia , Audição/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Discriminação da Altura Tonal/fisiologia , Testes de Impedância Acústica , Adolescente , Adulto , Humanos , Masculino , Militares , Otoscopia , Adulto Jovem
18.
NPJ Vaccines ; 3: 10, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29560282

RESUMO

This study demonstrates that the fate of a vaccine is influenced by the cytokines produced by the innate lymphoid cells (ILC) recruited to the vaccination site, and it is vaccine route and adjuvant dependent. Intranasal virus vaccination induced ST2/IL-33R+ ILC2 in lung, while intramuscular vaccination induced exclusively IL-25R+ ILC2 in muscle. Interestingly, a larger proportion of IL-13+ ILC2s were detected in muscle following i.m. viral vector vaccination compared to lung post i.n. delivery. These observations revealed that ILC2 were the main source of IL-13 at the vaccination site (24 h post vaccination) responsible for inducing T cells of varying avidities. Moreover, recombinant fowlpox viral vector-based vaccines expressing adjuvants that transiently block IL-13 signalling at the vaccination site using different mechanisms (IL-4R antagonist or IL-13Rα2 adjuvants), revealed that the level of IL-13 present in the milieu also significantly influenced IFN-γ, IL-22 or IL-17A expression by ILC1/ILC3. Specifically, an early IL-13 and IFN-γ co-dependency at the ILC level may also be associated with shaping the downstream antibody responses, supporting the notion that differentially regulating IL-13 signalling via STAT6 or IL-13Rα2 pathways can modify ILC function and the resulting adaptive T- and B-cell immune outcomes reported previously. Moreover, unlike chronic inflammatory or experimentally induced conditions, viral vector vaccination induced uniquely different ILC profiles (i.e., expression of CD127 only on ILC2 not ILC1/ILC3; expression of IFN-γ in both NKP46+ and NKp46- ILCs). Collectively, our data highlight that tailoring a vaccine vector/adjuvant to modulate the ILC cytokine profile according to the target pathogen, may help design more efficacious vaccines in the future.

20.
Hear Res ; 226(1-2): 70-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16839720

RESUMO

The otoprotective peptide AM-111, a cell-permeable inhibitor of JNK mediated apoptosis, was tested for its efficacy as a rescue agent following impulse noise trauma. Single dose administrations of AM-111 at 1h or 4h post-impulse noise exposure (155 dB peak SPL) via systemic or local routes were evaluated with a total of 48 chinchillas. The animals received the compound either by IP injection or locally onto the round window membrane (hyaluronic acid gel formulation or osmotic mini-pump). Efficacy was determined by auditory brainstem responses (ABR) as well as cytocochleograms. Three weeks after impulse noise exposure, permanent threshold shifts (PTS) were significantly lower for AM-111 treated ears compared to controls, regardless of the drug administration route and the time point of drug delivery. Even the treatments which started 4h post-noise exposure, reduced hearing loss in the 2-8 kHz range compared to controls by up to 16-25 dB to a PTS as low as 6-17 dB, demonstrating significant protection against permanent hearing loss from impulse noise trauma. These findings suggest a key role for JNK mediated cochlear sensory cell death from oxidative stress.


Assuntos
Perda Auditiva Provocada por Ruído/prevenção & controle , Peptídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Chinchila , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Feminino , Géis , Células Ciliadas Auditivas/efeitos dos fármacos , Células Ciliadas Auditivas/patologia , Perda Auditiva Provocada por Ruído/enzimologia , Perda Auditiva Provocada por Ruído/patologia , Perda Auditiva Provocada por Ruído/fisiopatologia , Bombas de Infusão Implantáveis , Injeções Intraperitoneais , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Peptídeos/administração & dosagem
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