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1.
Commun Biol ; 5(1): 1385, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536097

RESUMO

There is debate in the field of oncolytic virus (OV) therapy, whether a single viral dose, or multiple administrations, is better for tumor control. Using intravital microscopy, we describe the fate of vesicular stomatitis virus (VSV) delivered systemically as a first or a second dose. Following primary administration, VSV binds to the endothelium, initiates tumor infection and activates a proinflammatory response. This initial OV dose induces neutrophil migration into the tumor and limits viral replication. OV administered as a second dose fails to infect the tumor and is captured by intravascular monocytes. Despite a lack of direct infection, this second viral dose, in a monocyte-dependent fashion, enhances and sustains infection by the first viral dose, promotes CD8 T cell recruitment, delays tumor growth and improves survival in multi-dosing OV therapy. Thus, repeated VSV dosing engages monocytes to post-condition the tumor microenvironment for improved infection and anticancer T cell responses. Understanding the complex interactions between the subsequent viral doses is crucial for improving the efficiency of OV therapy and virus-based vaccines.


Assuntos
Neoplasias , Terapia Viral Oncolítica , Vírus Oncolíticos , Rhabdoviridae , Animais , Camundongos , Monócitos , Microambiente Tumoral
2.
Neurocrit Care ; 35(3): 617-630, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34061312

RESUMO

BACKGROUND: Neurological injury can alter the systemic immune system, modifying the functional capacity of immune cells and causing a dysfunctional balance of cytokines, although mechanisms remain incompletely understood. The objective of this study was to assess the temporal relationship between changes in the activation status of circulating invariant natural killer T (iNKT) cells and the balance of plasma cytokines among critically ill patients with neurological injury. METHODS: We conducted an exploratory prospective observational study of adult (18 years or older) intensive care unit (ICU) patients with acute neurological injury (n = 20) compared with ICU patients without neurological injury (n = 22) and healthy controls (n = 10). Blood samples were collected on days 1, 2, 4, 7, 14, and 28 following ICU admission to analyze the activation status of circulating iNKT cells by flow cytometry and the plasma concentration of inflammation-relevant immune mediators, including T helper 1 (TH1) and T helper 2 (TH2) cytokines, by multiplex bead-based assay. RESULTS: Invariant natural killer T cells were activated in both ICU patient groups compared with healthy controls. Neurological patients had decreased levels of multiple immune mediators, including TH1 cytokines (interferon-γ, tumor necrosis factor-α, and interleukin-12p70), indicative of immunosuppression. This led to a greater than twofold increase in the ratio of TH2/TH1 cytokines early after injury (days 1 - 2) compared with healthy controls, a shift that was also observed for ICU controls. Systemic TH2/TH1 cytokine ratios were positively associated with iNKT cell activation in the neurological patients and negatively associated in ICU controls. These relationships were strongest for the CD4+ iNKT cell subset compared with the CD4- iNKT cell subset. The relationships to individual cytokines similarly differed between patient groups. Forty percent of the neurological patients developed an infection; however, differences for the infection subgroup were not identified. CONCLUSIONS: Critically ill patients with neurological injury demonstrated altered systemic immune profiles early after injury, with an association between activated peripheral iNKT cells and elevated systemic TH2/TH1 cytokine ratios. This work provides further support for a brain-immune axis and the ability of neurological injury to have far-reaching effects on the body's immune system.


Assuntos
Células T Matadoras Naturais , Estado Terminal , Citocinas , Citometria de Fluxo , Humanos , Interferon gama
3.
J Speech Lang Hear Res ; 64(1): 16-29, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33306439

RESUMO

Purpose This study aims to investigate the effects of dysphonic voice on speech intelligibility in Cantonese-speaking adults. Method Speech recordings from three speakers with dysphonia secondary to phonotrauma and three speakers with healthy voices were presented to 30 healthy listeners (15 men and 15 women; M age = 22.7 years) under six noise conditions (signal-to-noise ratio [SNR] -10, SNR -5, SNR 0, SNR +5, SNR +10) and quiet conditions. The speech recordings were composed of sentences with five different lengths: five syllables, eight syllables, 10 syllables, 12 syllables, and 15 syllables. The effects of speaker's voice quality, background noise condition, and sentence length on speech intelligibility were examined. Speech intelligibility scores were calculated based on the listener's correct judgment of the number of syllables heard as a percentage of the total syllables in each stimulus. Results Dysphonic voices, as compared to healthy voices, were significantly more affected by background noise. Speech presented with dysphonic voices was significantly less intelligible than speech presented with healthy voices under unfavorable SNR conditions (SNR -10, SNR -5, and SNR 0 conditions). However, there was no sufficient evidence to suggest effects of sentence length on intelligibility, regardless of the speaker's voice quality or the level of background noise. Conclusions This study provides empirical data on the impacts of dysphonic voice on speech intelligibility in Cantonese speakers. The findings highlight the importance of educating the public about the impacts of voice quality and background noise on speech intelligibility and the potential of compensatory strategies that specifically address these barriers. Supplemental Material https://doi.org/10.23641/asha.13335926.


Assuntos
Disfonia , Percepção da Fala , Voz , Adulto , Feminino , Humanos , Masculino , Inteligibilidade da Fala , Qualidade da Voz , Adulto Jovem
4.
Blood ; 129(10): 1357-1367, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28073784

RESUMO

Neutrophil extracellular traps (NETs; webs of DNA coated in antimicrobial proteins) are released into the vasculature during sepsis where they contribute to host defense, but also cause tissue damage and organ dysfunction. Various components of NETs have also been implicated as activators of coagulation. Using multicolor confocal intravital microscopy in mouse models of sepsis, we observed profound platelet aggregation, thrombin activation, and fibrin clot formation within (and downstream of) NETs in vivo. NETs were critical for the development of sepsis-induced intravascular coagulation regardless of the inciting bacterial stimulus (gram-negative, gram-positive, or bacterial products). Removal of NETs via DNase infusion, or in peptidylarginine deiminase-4-deficient mice (which have impaired NET production), resulted in significantly lower quantities of intravascular thrombin activity, reduced platelet aggregation, and improved microvascular perfusion. NET-induced intravascular coagulation was dependent on a collaborative interaction between histone H4 in NETs, platelets, and the release of inorganic polyphosphate. Real-time perfusion imaging revealed markedly improved microvascular perfusion in response to the blockade of NET-induced coagulation, which correlated with reduced markers of systemic intravascular coagulation and end-organ damage in septic mice. Together, these data demonstrate, for the first time in an in vivo model of infection, a dynamic NET-platelet-thrombin axis that promotes intravascular coagulation and microvascular dysfunction in sepsis.


Assuntos
Coagulação Intravascular Disseminada/imunologia , Armadilhas Extracelulares/imunologia , Sepse/imunologia , Animais , Plaquetas/imunologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal
5.
Hong Kong Med J ; 22(2): 116-23, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26823386

RESUMO

OBJECTIVES: This study aimed to measure cardiac output, systemic vascular resistance, cardiac index, and systemic vascular resistance index in emergency department patients with poorly controlled hypertension; and to determine the frequency in which antihypertensive drugs prescribed do not address the predominant haemodynamic abnormality. METHODS: This cross-sectional observational study was conducted in an emergency department of a 1400-bed tertiary hospital in Hong Kong. Patients aged 18 years or above, with systolic blood pressure of ≥160 mm Hg or diastolic blood pressure of ≥100 mm Hg based on two or more measurements and on two separate occasions within 2 to 14 days, were included. Haemodynamic measurements were obtained using a non-invasive Doppler ultrasound monitor. Doctors were blinded to the haemodynamic data. Any antihypertensive medication adjustment was evaluated for correlation with haemodynamic changes. RESULTS: Overall, 164 patients were included. Their mean age was 69.0 years and 97 (59.1%) were females. Systemic vascular resistance and cardiac output were elevated in 65.8% (95% confidence interval, 57.9-72.9%) and 15.8% (10.8-22.5%) of patients, respectively. Systemic vascular resistance index and cardiac index were elevated in 43.9% (95% confidence interval, 36.2-51.8%) and 19.5% (13.9-26.5%) of patients, respectively. Of 71 patients in whom antihypertensive medications were adjusted, 25 (35.2%; 95% confidence interval, 24.5-47.5%) were prescribed agents that did not correlate with the primary haemodynamic abnormality. CONCLUSIONS: The profile of haemodynamic changes in emergency department patients with poorly controlled hypertension is characterised. The antihypertensive drugs prescribed did not correspond to the patient's primary haemodynamic derangement in 35% of cases.


Assuntos
Anti-Hipertensivos/uso terapêutico , Serviço Hospitalar de Emergência , Hemodinâmica/fisiologia , Hipertensão/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Estudos Transversais , Feminino , Hong Kong , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Ultrassonografia Doppler , Resistência Vascular/fisiologia
6.
Eur J Emerg Med ; 22(2): 128-34, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24802104

RESUMO

OBJECTIVE: This study aimed to establish learning profiles for noninvasive transcutaneous Doppler ultrasound. MATERIALS AND METHODS: Four trainees attended a 2-h lecture, followed by a 15-min demonstration on a volunteer and a 30-min hands-on workshop in a small group setting. Then, they underwent hands-on practice on 50 participants without supervision. The skill acquisitions in terms of signal magnitude, signal quality, and measurement time of the trainees were evaluated through 50 assessments, and were compared with that of a trainer with extensive experience on the use of an ultrasonic cardiac output monitor acting as a 'gold standard'. The learning profile for each individual trainee was analyzed using the cumulative sum graphical method. RESULTS: Four trainees performed ultrasonic cardiac output monitor on 50 participants. All trainees attained proficiency after 18-36 assessments to achieve aortic signal magnitude and quality comparable with the trainer. It requires a minimum of nine assessments to obtain three aortic scans within 5 min with 95% success rates. Only half of the trainees achieved competence in pulmonary scans and the minimum number of assessments required was 36. A minimum of 22 assessments were required for three pulmonary scans within 10 min with 95% success rates. CONCLUSION: A substantial period of learning needs to be undertaken to achieve proficiency on the use of noninvasive transcutaneous Doppler ultrasound. Cumulative sum analysis is a useful tool for ongoing quality assessment during medical education and training in practical procedures on an individual basis.


Assuntos
Baixo Débito Cardíaco/diagnóstico por imagem , Competência Clínica , Educação de Pós-Graduação em Medicina/métodos , Hemodinâmica/fisiologia , Curva de Aprendizado , Ultrassonografia Doppler/métodos , Adulto , Estudos de Coortes , Cuidados Críticos , Educação Profissionalizante/métodos , Medicina de Emergência/educação , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Monitorização Fisiológica/métodos , Estudos Prospectivos , Volume Sistólico/fisiologia
7.
Physiol Rep ; 1(4): e00062, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24303147

RESUMO

A proper alignment of the ultrasound beam to the aortic or pulmonary outflow tracts is essential to acquire accurate signals. This study aimed to investigate the influence of different positions on the acquisition of Doppler signals using a noninvasive transcutaneous Doppler ultrasound. This was a prospective observational crossover study. Two operators performed hemodynamics measurements on each subject in supine, sitting, semirecumbent, passive leg raising (PLR) 20°, and PLR 60° positions using both aortic and pulmonary approaches. All Doppler flow profile images were assessed using the Fremantle and Prince of Wales Hospital criteria. Time required to obtain Doppler signals was recorded. A total of 60 subjects (50% males) aged 18-60 years old were investigated. In both sitting and semirecumbent positions, aortic stroke volume indexes (SVIs) and cardiac indexes (CIs) were significantly lower than those in the other three positions while the pulmonary CIs were comparable to that in the supine position. In the sitting position, the aortic signal qualities were lower and the time to obtain the pulmonary Doppler signals was prolonged. Instead, the signal quality and the time to obtain the Doppler signals in the semirecumbent position were similar to those in the other three positions using the pulmonary approach. PLR did not cause a significant increase in SVI regardless of the degree of leg elevation. These data show that it is feasible to perform the noninvasive transcutaneous Doppler ultrasound using the pulmonary approach in the semirecumbent position for patients unable to maintain the supine position. The aortic approach in the sitting and semirecumbent positions is not suitable as it is not sufficiently reliable.

8.
Drug Metab Rev ; 45(2): 173-95, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23600686

RESUMO

A plethora of studies have demonstrated the expression of cytochrome P450 (CYP) and soluble epoxide hydrolase (sEH) enzymes in the heart and other cardiovascular tissues. In addition, the expression of these enzymes is altered during several cardiovascular diseases (CVDs), including cardiac hypertrophy (CH). The alteration in CYP and sEH expression results in derailed CYP-mediated arachidonic acid (AA) metabolism. In animal models of CH, it has been reported that there is an increase in 20-hydroxyeicosatetraenoic acid (20-HETE) and a decrease in epoxyeicosatrienoic acids (EETs). Further, inhibiting 20-HETE production by CYP ω-hydroxylase inhibitors and increasing EET stability by sEH inhibitors have been proven to protect against CH as well as other CVDs. Therefore, CYP-mediated AA metabolites 20-HETE and EETs are potential key players in the pathogenesis of CH. Some studies have investigated the molecular mechanisms by which these metabolites mediate their effects on cardiomyocytes and vasculature leading to pathological CH. Activation of several intracellular signaling cascades, such as nuclear factor of activated T cells, nuclear factor kappa B, mitogen-activated protein kinases, Rho-kinases, Gp130/signal transducer and activator of transcription, extracellular matrix degradation, apoptotic cascades, inflammatory cytokines, and oxidative stress, has been linked to the pathogenesis of CH. In this review, we discuss how 20-HETE and EETs can affect these signaling pathways to result in, or protect from, CH, respectively. However, further understanding of these metabolites and their effects on intracellular cascades will be required to assess their potential translation to therapeutic approaches for the prevention and/or treatment of CH and heart failure.


Assuntos
Ácido Araquidônico/metabolismo , Cardiomegalia/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Animais , Cardiomegalia/patologia , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Transdução de Sinais
9.
Vascul Pharmacol ; 58(5-6): 363-73, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23466634

RESUMO

We have previously shown that isoproterenol-induced cardiac hypertrophy causes significant changes to cytochromes P450 (CYPs) and soluble epoxide hydrolase (sEH) gene expression. Therefore, in this study, we examined the effect of isoproterenol in H9c2 cells, and the protective effects of 14,15-EET against isoproterenol-induced cellular hypertrophy. Isoproterenol was incubated with H9c2 cells for 24 and 48 h. To determine the protective effects of 14,15-EET, H9c2 cells were incubated with isoproterenol in the absence and presence of 14,15-EET. Thereafter, the expression of hypertrophic markers and different CYP genes were determined by real time-PCR. Our results demonstrated that isoproterenol significantly increased the expression of hypertrophic marker, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), parallel to a significant increase in cell surface area. Also, isoproterenol increased the mRNA expression of CYP1A1, CYP1B1, CYP2J3, CYP4F4 and CYP4F5, as well as the gene encoding sEH, EPHX2. On other hand, 14,15-EET significantly attenuated the isoproterenol-mediated induction of ANP, BNP, CYP1A1, CYP2J3, CYP4F4, CYP4F5 and EPHX2. Moreover 14,15-EET prevented the isoproterenol-mediated increase in cell surface area. Interestingly, 20-hydroxyeicosatetraenoic acid (20-HETE) treatment caused similar effects to that of isoproterenol treatment and induced cellular hypertrophy in H9c2 cells. In conclusion, isoproterenol induces cellular hypertrophy and modulates the expression of CYPs and EPHX2 in H9c2 cells. Furthermore, 14,15-EET exerts a protective effect against isoproterenol-induced cellular hypertrophy whereas, 20-HETE induced cellular hypertrophy in H9c2 cells.


Assuntos
Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Cardiomegalia/prevenção & controle , Isoproterenol/toxicidade , Miócitos Cardíacos/efeitos dos fármacos , Ácido 8,11,14-Eicosatrienoico/farmacologia , Animais , Cardiomegalia/induzido quimicamente , Linhagem Celular , Sistema Enzimático do Citocromo P-450/genética , Epóxido Hidrolases/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Ácidos Hidroxieicosatetraenoicos/toxicidade , Miócitos Cardíacos/patologia , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
10.
Br J Pharmacol ; 168(8): 1794-807, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23176298

RESUMO

BACKGROUND AND PURPOSE: We have previously shown that isoprenaline-induced cardiac hypertrophy causes significant changes in the expression of cytochromes P450 (CYP) and soluble epoxide hydrolase (sEH) genes. Therefore, it is important to examine whether the inhibition of sEH by 1-(1-methanesulfonyl-piperidin-4-yl)-3-(4-trifluoromethoxy-phenyl)-urea (TUPS) will protect against isoprenaline-induced cardiac hypertrophy. EXPERIMENTAL APPROACH: Male Sprague-Dawley rats were treated with TUPS (0.65 mg kg(-1) day(-1), p.o.), isoprenaline (5 mg kg(-1) day(-1), i.p.) or the combination of both. In vitro H9c2 cells were treated with isoprenaline (100 µM) in the presence and absence of either TUPS (1 µM) or 11,12 EET (1 µM). The expression of hypertrophic, fibrotic markers and different CYP genes were determined by real-time PCR. KEY RESULTS: Isoprenaline significantly induced the hypertrophic, fibrotic markers as well as the heart to body weight ratio, which was significantly reversed by TUPS. Isoprenaline also caused an induction of CYP1A1, CYP1B1, CYP2B1, CYP2B2, CYP4A3 and CYP4F4 gene expression and TUPS significantly inhibited this isoprenaline-mediated effect. Moreover, isoprenaline significantly reduced 5,6-, 8,9-, 11,12- and 14,15-EET and increased their corresponding 8,9-, 11,12- and 14,15-dihydroxyeicosatrienoic acid (DHET) and the 20-HETE metabolites. TUPS abolished these isoprenaline-mediated changes in arachidonic acid (AA) metabolites. In H9c2 cells, isoprenaline caused a significant induction of ANP, BNP and EPHX2 mRNA levels. Both TUPS and 11,12-EET significantly decreased this isoprenaline-mediated induction of ANP, BNP and EPHX2. CONCLUSIONS AND IMPLICATIONS: TUPS partially protects against isoprenaline-induced cardiac hypertrophy, which confirms the role of sEH and CYP enzymes in the development of cardiac hypertrophy.


Assuntos
Cardiomegalia/prevenção & controle , Cardiotônicos/administração & dosagem , Sistema Enzimático do Citocromo P-450/metabolismo , Epóxido Hidrolases/antagonistas & inibidores , Isoproterenol/efeitos adversos , Compostos de Fenilureia/administração & dosagem , Piperidinas/administração & dosagem , Animais , Fator Natriurético Atrial/metabolismo , Peso Corporal/efeitos dos fármacos , Cardiomegalia/induzido quimicamente , Linhagem Celular , Sistema Enzimático do Citocromo P-450/genética , Antagonismo de Drogas , Epóxido Hidrolases/genética , Epóxido Hidrolases/metabolismo , Regulação da Expressão Gênica , Coração/efeitos dos fármacos , Humanos , Rim/metabolismo , Fígado/metabolismo , Peptídeo Natriurético Encefálico/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
12.
Osteoporos Int ; 16(12): 1907-16, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16133646

RESUMO

The Chinese diet is low in calcium, including among adolescent girls, with an average intake around 500 mg per day. In this study, we compared the percentage change in bone mineral density and content of the spine and hip region in a 1-year follow-up study between 104 adolescent girls aged 14 to 16 years receiving 375 ml calcium-fortified soymilk supplementation and 95 girls in the control group. The mean percentage changes of bone mineral density/content (BMD/BMC) and standard deviation (SD) at 1 year for the supplementation and control groups were as follows: neck of the femur BMD 2.7+/-2.94%, 1.8+/-3.49% (P = 0.08); trochanter BMD 3.3+/-3.27%, 1.6+/-2.94% (P < or = 0.001); intertrochanter BMD 3.6+/-3.05%, 2.32+/-2.95% (P = 0.002); total hip BMD 3.1+/-2.39%, 2.05+/-2.22% (P = 0.001); total hip BMC 3.8+/-3.05%, 2.6+/-2.96% (P = 0.006). The percent difference between the percentage of bone changes in the supplementation and control groups [100x (soymilk-control)/control] ranged from 45 to 113%. We observed no differences in the spine BMD/C and no differences in changes of height and weight between the soymilk supplementation and control groups, which yielded similar results. Stepwise multivariate regression analysis including height, weight, growth stage, dietary energy, protein, calcium from usual diet and physical activity also showed that supplementation was significantly associated with a percentage increase in BMD/C at the hip. We conclude that 375 ml calcium-fortified soymilk supplementation, or an equivalent of about two glasses, is among the effective strategies for bone acquisition and the optimization of peak bone mass in adolescent girls.


Assuntos
Densidade Óssea/fisiologia , Cálcio da Dieta/administração & dosagem , Alimentos Fortificados , Leite de Soja/administração & dosagem , Adolescente , Biomarcadores/análise , Tamanho Corporal/fisiologia , Desenvolvimento Ósseo/fisiologia , China/epidemiologia , Suplementos Nutricionais , Ingestão de Energia/fisiologia , Exercício Físico/fisiologia , Feminino , Quadril , Humanos , Estudos Prospectivos , Coluna Vertebral
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