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1.
Clin Exp Immunol ; 208(3): 301-315, 2022 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-35404420

RESUMEN

Vδ2+ T cells can recognize malignantly transformed cells as well as those infected with mycobacteria. This cross-reactivity supports the idea of using mycobacteria to manipulate Vδ2+ T cells in cancer immunotherapy. To date, therapeutic interventions using Vδ2+ T cells in cancer have involved expanding these cells in or ex vivo using zoledronic acid (ZA). Here, we show that the mycobacterium Bacillus Calmette-Guérin (BCG) also causes Vδ2+ T-cell expansion in vitro and that resulting Vδ2+ cell populations are cytotoxic toward tumour cell lines. We show that both ZA and BCG-expanded Vδ2+ cells effectively killed both Daudi and THP-1 cells. THP-1 cell killing by both ZA and BCG-expanded Vδ2+ cells was enhanced by treatment of targets cells with ZA. Although no difference in cytotoxic activity between ZA- and BCG-expanded Vδ2+ cells was observed, BCG-expanded cells degranulated more and produced a more diverse range of cytokines upon tumour cell recognition compared to ZA-expanded cells. ZA-expanded Vδ2+ cells were shown to upregulate exhaustion marker CD57 to a greater extent than BCG-expanded Vδ2+ cells. Furthermore, ZA expansion was associated with upregulation of inhibitory markers PD-1 and TIM3 in a dose-dependent manner whereas PD-1 expression was not increased following expansion using BCG. Intradermal BCG vaccination of rhesus macaques caused in vivo expansion of Vδ2+ cells. In combination with the aforementioned in vitro data, this finding suggests that BCG treatment could induce expansion of Vδ2+ T cells with enhanced anti-tumour potential compared to ZA treatment and that either ZA or BCG could be used intratumourally as a means to potentiate stronger anti-tumour Vδ2+ T-cell responses.


Asunto(s)
Mycobacterium bovis , Linfocitos T , Animales , Vacuna BCG , Activación de Linfocitos , Macaca mulatta/metabolismo , Receptor de Muerte Celular Programada 1 , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Ácido Zoledrónico/farmacología
3.
Mol Imaging Biol ; 21(1): 19-24, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29845428

RESUMEN

PURPOSE: Computed tomography (CT) images enable capturing specific manifestations of tuberculosis (TB) that are undetectable using common diagnostic tests, which suffer from limited specificity. In this study, we aimed to automatically quantify the burden of Mycobacterium tuberculosis (Mtb) using biomarkers extracted from x-ray CT images. PROCEDURES: Nine macaques were aerosol-infected with Mtb and treated with various antibiotic cocktails. Chest CT scans were acquired in all animals at specific times independently of disease progression. First, a fully automatic segmentation of the healthy lungs from the acquired chest CT volumes was performed and air-like structures were extracted. Next, unsegmented pulmonary regions corresponding to damaged parenchymal tissue and TB lesions were included. CT biomarkers were extracted by classification of the probability distribution of the intensity of the segmented images into three tissue types: (1) Healthy tissue, parenchyma free from infection; (2) soft diseased tissue, and (3) hard diseased tissue. The probability distribution of tissue intensities was assumed to follow a Gaussian mixture model. The thresholds identifying each region were automatically computed using an expectation-maximization algorithm. RESULTS: The estimated longitudinal course of TB infection shows that subjects that have followed the same antibiotic treatment present a similar response (relative change in the diseased volume) with respect to baseline. More interestingly, the correlation between the diseased volume (soft tissue + hard tissue), which was manually delineated by an expert, and the automatically extracted volume with the proposed method was very strong (R2 ≈ 0.8). CONCLUSIONS: We present a methodology that is suitable for automatic extraction of a radiological biomarker from CT images for TB disease burden. The method could be used to describe the longitudinal evolution of Mtb infection in a clinical trial devoted to the design of new drugs.


Asunto(s)
Carga Bacteriana/métodos , Biomarcadores/análisis , Tomografía Computarizada por Rayos X/métodos , Tuberculosis Pulmonar/diagnóstico , Algoritmos , Animales , Progresión de la Enfermedad , Imagenología Tridimensional , Estudios Longitudinales , Pulmón/diagnóstico por imagen , Pulmón/microbiología , Pulmón/patología , Macaca fascicularis , Masculino , Mycobacterium tuberculosis/citología , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Tuberculosis Pulmonar/microbiología
4.
Eur Phys J C Part Fields ; 77(2): 112, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29033670

RESUMEN

We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor [Formula: see text], arising in the semileptonic [Formula: see text] transition at zero momentum transfer, as well as the decay constant ratio [Formula: see text] and its consequences for the CKM matrix elements [Formula: see text] and [Formula: see text]. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of [Formula: see text] and [Formula: see text] Chiral Perturbation Theory. We review the determination of the [Formula: see text] parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for [Formula: see text] and [Formula: see text] (also new compared to the previous review), as well as those for D- and B-meson-decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant [Formula: see text].

5.
PLoS One ; 12(3): e0171906, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28273087

RESUMEN

BACKGROUND: New interventions for tuberculosis are urgently needed. Non-human primate (NHP) models provide the most relevant pre-clinical models of human disease and play a critical role in vaccine development. Models utilising Asian cynomolgus macaque populations are well established but the restricted genetic diversity of the Mauritian cynomolgus macaques may be of added value. METHODS: Mauritian cynomolgus macaques were exposed to a range of doses of M. tuberculosis delivered by aerosol, and the outcome was assessed using clinical, imaging and pathology-based measures. RESULTS: All macaques developed characteristic clinical signs and disease features of tuberculosis (TB). Disease burden and the ability to control disease were dependent on exposure dose. Mauritian cynomolgus macaques showed less variation in pulmonary disease burden and total gross pathology scores within exposure dose groups than either Indian rhesus macaques or Chinese cynomolgus macaques. CONCLUSIONS: The genetic homogeneity of Mauritian cynomolgus macaques makes them a potentially useful model of human tuberculosis.


Asunto(s)
Macaca fascicularis/microbiología , Mycobacterium tuberculosis/fisiología , Tuberculosis/patología , Animales , Ensayo de Immunospot Ligado a Enzimas , Interferón gamma/sangre , Interferón gamma/metabolismo , Riñón/patología , Hígado/patología , Pulmón/diagnóstico por imagen , Pulmón/microbiología , Pulmón/patología , Macaca fascicularis/inmunología , Imagen por Resonancia Magnética , Radiografía Torácica , Índice de Severidad de la Enfermedad
6.
Tuberculosis (Edinb) ; 101: 174-190, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27865390

RESUMEN

Intradermal (ID) BCG injection provides incomplete protection against TB in humans and experimental models. Alternative BCG vaccination strategies may improve protection in model species, including rhesus macaques. This study compares the immunogenicity and efficacy of BCG administered by ID and intravenous (IV) injection, or as an intratracheal mucosal boost (ID + IT), against aerosol challenge with Mycobacterium tuberculosis Erdman strain. Disease pathology was significantly reduced, and survival improved, by each BCG vaccination strategy, relative to unvaccinated animals. However, IV induced protection surpassed that achieved by all other routes, providing an opportunity to explore protective immunological mechanisms using antigen-specific IFN-γ ELISpot and polychromatic flow cytometry assays. IFN-γ spot forming units and multifunctional CD4 T-cell frequencies increased significantly following each vaccination regimen and were greatest following IV immunisation. Vaccine-induced multifunctional CD4 T-cells producing IFN-γ and TNF-α were associated with reduced disease pathology following subsequent M.tb challenge; however, high frequencies of this population following M.tb infection correlated with increased pathology. Cytokine producing T-cells primarily occupied the CD4 transitional effector memory phenotype, implicating this population as central to the mycobacterial response, potentially contributing to the stringent control observed in IV vaccinated animals. This study demonstrates the protective efficacy of IV BCG vaccination in rhesus macaques, offering a valuable tool for the interrogation of immunological mechanisms and potential correlates of protection.


Asunto(s)
Antígenos Bacterianos/inmunología , Vacuna BCG/administración & dosificación , Linfocitos T CD4-Positivos/inmunología , Mycobacterium tuberculosis/inmunología , Tuberculosis/prevención & control , Aerosoles , Animales , Vacuna BCG/efectos adversos , Vacuna BCG/inmunología , Progresión de la Enfermedad , Inmunidad Celular , Memoria Inmunológica , Inyecciones Intradérmicas , Inyecciones Intravenosas , Interferón gamma/biosíntesis , Macaca mulatta , Masculino , Tráquea , Tuberculosis/inmunología , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/prevención & control , Vacunación/métodos
7.
Aust Vet J ; 94(10): 387-93, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27671084

RESUMEN

OBJECTIVE: In Australia, Salmonella serovar Typhimurium (S. Typhimurium) is the predominant zoonotic serovar in humans and is frequently isolated from layer hens. Vaccination against this serovar has been previously shown to be effective in broilers and the aim of this current study was to assess and determine the best vaccination strategy (live or inactivated) to minimise caecal colonisation by S. Typhimurium. METHODS: A long-term experiment (56 weeks) was conducted on ISABROWN pullets using a commercial live aroA deleted mutant S. Typhimurium vaccine and an autogenous inactivated multivalent Salmonella vaccine (containing serovars Typhimurium, Infantis, Montevideo and Zanzibar). These vaccines were administered PO or by SC or IM injection, either alone or in combination. Pullets were vaccinated throughout rearing (to 18 weeks of age) and sequentially bled for antibody titre levels. The birds, vaccinated and controls, were challenged orally with a field isolate of S. Typhimurium at different ages, held for 21 days post-challenge, then euthanased and their caeca cultured for the presence of Salmonella. RESULTS: None of the oral live-vaccinated groups exhibited lasting protection. When administered twice, the inactivated vaccine gave significant protection at 17 weeks of age and the live vaccine given by SC injection given twice produced significant protection at 17, 25 and 34 weeks. CONCLUSIONS: Vaccination regimens that included parenteral administration of live or inactivated vaccines and thus achieved positive serum antibody levels were able to provide protection against challenge. Hence, vaccination may play a useful role in a management strategy for Salmonella carriage in layer flocks.


Asunto(s)
Pollos , Enfermedades de las Aves de Corral/prevención & control , Salmonelosis Animal/prevención & control , Vacunas contra la Salmonella , Salmonella typhimurium/inmunología , Animales , Australia , Ciego/microbiología , Femenino , Enfermedades de las Aves de Corral/inmunología , Salmonelosis Animal/inmunología , Vacunas contra la Salmonella/administración & dosificación , Vacunas contra la Salmonella/inmunología , Factores de Tiempo , Vacunas Atenuadas/administración & dosificación , Vacunas Atenuadas/inmunología , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología
8.
Clin Vaccine Immunol ; 22(9): 992-1003, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26108288

RESUMEN

Nine million cases of tuberculosis (TB) were reported in 2013, with a further 1.5 million deaths attributed to the disease. When delivered as an intradermal (i.d.) injection, the Mycobacterium bovis BCG vaccine provides limited protection, whereas aerosol delivery has been shown to enhance efficacy in experimental models. In this study, we used the rhesus macaque model to characterize the mucosal and systemic immune response induced by aerosol-delivered BCG vaccine. Aerosol delivery of BCG induced both Th1 and Th17 cytokine responses. Polyfunctional CD4 T cells were detected in bronchoalveolar lavage (BAL) fluid and peripheral blood mononuclear cells (PBMCs) 8 weeks following vaccination in a dose-dependent manner. A similar trend was seen in peripheral gamma interferon (IFN-γ) spot-forming units measured by enzyme-linked immunosorbent spot (ELISpot) assay and serum anti-purified protein derivative (PPD) IgG levels. CD8 T cells predominantly expressed cytokines individually, with pronounced tumor necrosis factor alpha (TNF-α) production by BAL fluid cells. T-cell memory phenotype analysis revealed that CD4 and CD8 populations isolated from BAL fluid samples were polarized toward an effector memory phenotype, whereas the frequencies of peripheral central memory T cells increased significantly and remained elevated following aerosol vaccination. Expression patterns of the α4ß1 integrin lung homing markers remained consistently high on CD4 and CD8 T cells isolated from BAL fluid and varied on peripheral T cells. This characterization of aerosol BCG vaccination highlights features of the resulting mycobacterium-specific immune response that may contribute to the enhanced protection previously reported in aerosol BCG vaccination studies and will inform future studies involving vaccines delivered to the mucosal surfaces of the lung.


Asunto(s)
Vacuna BCG/administración & dosificación , Vacuna BCG/inmunología , Pulmón/inmunología , Pulmón/microbiología , Mycobacterium bovis/inmunología , Aerosoles , Animales , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Citocinas/biosíntesis , Citocinas/inmunología , Citometría de Flujo , Memoria Inmunológica/inmunología , Integrina alfa4beta1 , Interferón gamma/inmunología , Leucocitos Mononucleares/inmunología , Macaca mulatta , Modelos Animales , Células TH1/inmunología , Células Th17/inmunología
10.
J Comp Pathol ; 152(2-3): 217-26, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25481611

RESUMEN

Three rhesus macaques (Macaca mulatta) were challenged with Mycobacterium tuberculosis (Mtb), Erdman strain, as part of studies to investigate lesion development at early time points in tuberculosis (TB) and to assess computed tomography (CT) as a method of monitoring disease progression in vivo. Animals were challenged with either a high, mid or low dose of aerosolized Mtb. The low-dose animal was killed humanely at 24 days post challenge (dpc) and the remaining animals at 25 dpc. Abnormalities in clinical parameters were observed in all animals, but clinical signs relating to respiratory disease were not seen. Pulmonary changes consistent with TB infection were detected by CT at 21 dpc and magnetic resonance imaging (MRI) post mortem. Pulmonary nodule counts obtained from both imaging techniques were directly proportional to the challenge dose and correlated with gross and microscopical lesion counts. On gross and microscopical examination, lesions of similar size and morphology were observed in the lungs of all three animals, with the majority containing necrotic foci. Concomitant gross and microscopical, granulomatous lesions were observed in the tracheobronchial lymph nodes of all animals together with evidence of systemic spread. These findings further contribute to our understanding and knowledge of early lesion formation in the lungs of non-human primates.


Asunto(s)
Modelos Animales de Enfermedad , Tuberculosis Pulmonar/patología , Aerosoles , Animales , Femenino , Macaca mulatta , Masculino , Mycobacterium tuberculosis
11.
Eur Phys J C Part Fields ; 74(9): 2890, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25972762

RESUMEN

We review lattice results related to pion, kaon, [Formula: see text]- and [Formula: see text]-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor [Formula: see text], arising in semileptonic [Formula: see text] transition at zero momentum transfer, as well as the decay-constant ratio [Formula: see text] of decay constants and its consequences for the CKM matrix elements [Formula: see text] and [Formula: see text]. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of [Formula: see text] and [Formula: see text] Chiral Perturbation Theory and review the determination of the [Formula: see text] parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, we focus here on [Formula: see text]- and [Formula: see text]-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant [Formula: see text].

12.
J Comp Pathol ; 149(4): 475-85, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23880551

RESUMEN

As part of a study to investigate early changes following exposure to aerosols of Mycobacterium tuberculosis (Mtb), 10 rhesus macaques (Macaca mulatta) were infected with high (731 colony forming units [cfu]), medium (70 cfu) or low (7 cfu) doses of Mtb, and tissues were examined at 2 and 3 weeks post infection (wpi). Clinical disease was not observed. Results of advanced imaging and pathological findings were compared with respect to the delivered dose and time post infection. Magnetic resonance imaging revealed lesions in the lungs at these early time points ex vivo immediately prior to detailed post-mortem examination in the absence of clinical disease. In animals exposed to high and medium doses of Mtb that were studied at 2 and 3 wpi, a range of lesions including small foci of mainly mononuclear cells, primarily macrophages (granulomatous lesions), as well as obvious granulomas, were observed microscopically in the lungs, including lymphatics and hilar lymph nodes. In the low-dose group at 3 weeks, small lesions were identified in the lung and hilar lymph nodes of one animal, and the remaining two animals in this group had lesions in either lung or hilar lymph node. Acid fast bacilli were demonstrated in the lung and lymph nodes in all animals that received high and medium doses, and the lymph nodes of two animals at the low dose. A dose-dependent effect was observed with increasing dose and time post infection. Furthermore, early dissemination of bacilli to the draining, hilar lymph nodes with concomitant granulomatous lesion formation was observed. By contributing to the recognition of early lesion development due to aerosol challenge of Mtb in the rhesus macaque, this study forms a basis for further investigation of early lesions and may inform the design of future vaccine and therapeutic studies involving early time points in this species.


Asunto(s)
Exposición por Inhalación/efectos adversos , Tuberculosis Pulmonar/patología , Tuberculosis/patología , Aerosoles , Animales , Modelos Animales de Enfermedad , Macaca mulatta , Masculino
13.
Clin Vaccine Immunol ; 20(5): 663-72, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23446219

RESUMEN

Tuberculosis (TB) is a reemerging disease. The only available vaccine, Mycobacterium bovis BCG, is delivered intradermally and confers highly variable efficacy against pulmonary disease. There is an urgent need for improved vaccination strategies. Murine studies suggest that immunizations delivered directly to the respiratory mucosa might be a more effective route of vaccination. This study compared the immunogenicity of a leading candidate tuberculosis (TB) vaccine, modified vaccinia virus Ankara expressing antigen 85A (MVA85A), in rhesus macaques, delivered either as an aerosol or as an intradermal boost immunization 12 weeks after an intradermal BCG prime vaccine. Aerosol vaccination was well tolerated. MVA85A delivered by aerosol or by intradermal injection induced antigen-specific immune responses in the periphery and the lung, with a trend toward the highest response when the compartment and route of delivery were matched. The ability of poxvirus-vectored vaccines delivered by the systemic route to induce responses in the mucosal immune compartment in macaques is in contrast to the independent compartmentalization of mucosal and systemic immune systems described in mice. Unlike intradermal vaccination, aerosol vaccination did not induce a detectable serum anti-vector antibody response. The delivery of vaccines to the lungs might provide an immunization strategy that limits the induction of systemic anti-vector immunity, which would be extremely useful in the development of improved vaccine strategies. This is the first study to show a recombinant MVA-vectored vaccine to be highly immunogenic when delivered by the aerosol route to nonhuman primates. These results provide important safety and proof-of-concept data for further evaluation of this route of immunization for use in human clinical trials.


Asunto(s)
Vacunas contra la Tuberculosis , Tuberculosis/inmunología , Tuberculosis/prevención & control , Administración por Inhalación , Animales , Antígenos Bacterianos/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunidad Mucosa/inmunología , Inmunización Secundaria , Macaca , Mycobacterium bovis/inmunología , Vacunas contra la Tuberculosis/administración & dosificación , Vacunas contra la Tuberculosis/efectos adversos , Vacunas contra la Tuberculosis/inmunología , Vacunación , Vacunas Atenuadas/administración & dosificación , Vacunas Atenuadas/efectos adversos , Vacunas Atenuadas/inmunología , Vacunas de ADN , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/efectos adversos , Vacunas Sintéticas/inmunología
14.
Equine Vet J ; 42(8): 738-45, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21039805

RESUMEN

REASONS FOR PERFORMING STUDY: The aetiology of genital squamous cell carcinoma (SCC) in horses remains unknown, but the similarity to the disease in man, for which papillomavirus infection has been shown to be a causal factor, requires to be investigated in horses. HYPOTHESIS: One or more novel papillomaviruses cause equine genital SCC and its associated premalignant lesions. METHODS: DNA was extracted from samples of equine genital SCC and performed rolling circle amplification, in order to identify closed circular DNA viral genomes within the samples. The amplified DNA was subcloned and sequenced and the DNA sequence compared to that of other papillomavirus genomes. Using PCR primers developed from these genomic DNA sequences, studies were then carried out in order to identify the frequency at which the viral DNA could be identified in equine genital cancer samples from horses in both the UK, Australia and Austria. Finally, in situ hybridisation using specific probes developed from this DNA sequence were used to confirm the presence of the viral RNA sequences in the neoplastic cells in these lesions. RESULTS: The full length genome of a novel papillomavirus species was characterised from the equine genital SCC tissue and termed Equus caballus papillomavirus-2 (EcPV-2). Viral DNA and RNA was identified in the genital tumour samples, but not in the adjacent histologically normal tissue. EcPV-2 DNA could not be identified in equine ocular or nasal carcinomas or within the scrotal skin or in most smegma samples obtained from tumour-free horses. Sequencing of amplicons, generated from the archived equine genital tumours, identified variations within E1 and E6 on DNA and predicted protein level. CONCLUSIONS: A novel papillomavirus, EcPV-2, is likely to play a causal role in the pathogenesis of equine genital epithelial tumours. POTENTIAL RELEVANCE: Identification of a papillomavirus causal for genital carcinomas in horses may lead to development of a vaccine that could be used to prevent this serious disease in horses. This would be analogous to man, where vaccination against oncogenic papillomavirus species is currently being used to help prevent cervical cancer.


Asunto(s)
Carcinoma de Células Escamosas/veterinaria , Neoplasias de los Genitales Femeninos/veterinaria , Neoplasias de los Genitales Masculinos/veterinaria , Enfermedades de los Caballos/etiología , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Animales , Carcinoma de Células Escamosas/virología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Femenino , Neoplasias de los Genitales Femeninos/virología , Neoplasias de los Genitales Masculinos/virología , Genoma Viral , Caballos , Masculino , Papillomaviridae/genética , Filogenia , ARN Viral/genética , ARN Viral/aislamiento & purificación
15.
Clin Vaccine Immunol ; 17(8): 1170-82, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20534795

RESUMEN

The establishment of an aerosol challenge model in nonhuman primates (NHPs) for the testing of vaccines against Mycobacterium tuberculosis would assist the global effort to optimize novel vaccination strategies. The endpoints used in preclinical challenge studies to identify measures of disease burden need to be accurate and sensitive enough to distinguish subtle differences and benefits afforded by different tuberculosis (TB) vaccine regimens when group sizes are inevitably small. This study sought to assess clinical and nonclinical endpoints as potentially sensitive measures of disease burden in a challenge study with rhesus macaques by using a new protocol of aerosol administration of M. tuberculosis. Immunological and clinical readouts were assessed for utility in vaccine evaluation studies. This is the first example of TB vaccine evaluation with rhesus macaques where long-term survival was one of the primary endpoints. However, we found that in NHP vaccine efficacy studies with maximum group sizes of six animals, survival did not provide a valuable endpoint. Two approaches used in human clinical trials for the evaluation of the gamma interferon (IFN-gamma) response to vaccination (enzyme-linked immunospot [ELISpot] assay and enzyme-linked immunosorbent assay [ELISA]) were included in this study. The IFN-gamma profiles induced following vaccination were found not to correlate with protection, nor did the level of purified protein derivative (PPD)-specific proliferation. The only readout to reliably distinguish vaccinated and unvaccinated NHPs was the determination of lung lesion burden using magnetic resonance (MR) imaging combined with stereology at the end of the study. Therefore, the currently proposed key markers were not shown to correlate with protection, and only imaging offered a potentially reliable correlate.


Asunto(s)
Aerosoles , Modelos Animales de Enfermedad , Inhalación , Mycobacterium tuberculosis/patogenicidad , Vacunas contra la Tuberculosis/inmunología , Tuberculosis Pulmonar/patología , Tuberculosis Pulmonar/prevención & control , Animales , Biomarcadores , Proliferación Celular , Determinación de Punto Final , Humanos , Interferón gamma/metabolismo , Leucocitos Mononucleares/inmunología , Pulmón/patología , Macaca mulatta , Imagen por Resonancia Magnética , Mycobacterium tuberculosis/inmunología , Enfermedades de los Primates/inmunología , Enfermedades de los Primates/patología , Enfermedades de los Primates/prevención & control , Radiografía Torácica , Análisis de Supervivencia , Vacunas contra la Tuberculosis/administración & dosificación , Tuberculosis Pulmonar/inmunología
16.
Tuberculosis (Edinb) ; 89(6): 405-16, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19879805

RESUMEN

Sensitive and reproducible methods are needed to measure the impact on the host following experimental challenge with Mycobacterium tuberculosis, in order to determine the degree of protection conferred by new vaccines. Here we compare how well different clinical and post-mortem measures of disease burden predict the response by the host to increasing doses of M. tuberculosis in rhesus and cynomolgus macaques. The total lung and lesion volume was quantified from magnetic resonance imaging (MRI) digital stacks obtained from lungs of M. tuberculosis infected animals that were formalin fixed and scanned ex-vivo. The total lung lesion volume relative to the fixed whole lung volume was superior at indicating disease burden when compared to thoracic radiography, pathology scores, changes in body weight and temperature, as well as erythrocyte haemoglobin concentrations and sedimentation rate. The total lesion volume accurately reflected differences in challenge doses of M. tuberculosis that ranged from 30 to 500 CFU delivered by aerosol. The determination of total lesion volume from MR images demonstrated a species-dependent difference between rhesus and cynomolgus macaques in susceptibility to M. tuberculosis infection. MR stereology provides an accurate, quantifiable and relatively simple assessment, which can be easily standardized between laboratories and should form an essential component of the clinical assessment of disease progression, or vaccine efficacy.


Asunto(s)
Pulmón/patología , Imagen por Resonancia Magnética , Mycobacterium tuberculosis/patogenicidad , Vacunas contra la Tuberculosis/farmacología , Tuberculosis Pulmonar/patología , Aerosoles , Animales , Modelos Animales de Enfermedad , Pulmón/inmunología , Macaca mulatta , Mycobacterium tuberculosis/inmunología , Reproducibilidad de los Resultados , Tuberculosis Pulmonar/inmunología
17.
J Biomech ; 41(5): 968-76, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18304555

RESUMEN

This study examined the transverse plane kinematics of the pelvis, thorax and head while participants walked at a range of speeds on a treadmill under three load conditions: no load, with a loaded backpack with no hip belt and with a loaded backpack with a hip belt. Research has suggested that one mechanism for adapting to heavy loads carried with no hip belt is to reduce the amplitudes and relative phase of transverse plane pelvic and thoracic rotations, in order to minimize rotational torque on the loaded upper body. Transverse plane rotation amplitudes of the pelvis, thorax, backpack and head were calculated from 3D kinematic data for 12 healthy subjects, walking at speeds of 0.5, 0.9, 1.3 and 1.7 ms(-1). Relative phase relation and its variability were also computed for pelvis-thorax rotations and backpack-thorax rotations. Stability of the coordination pattern was estimated as an inverse function of the variability in relative phase. The backpack with the hip belt allowed significantly larger transverse plane rotation amplitudes, along with increased stability of the coordination pattern, than the backpack with no hip belt. Motion patterns of the backpack and thorax suggested that the backpack frame was used to assist with the deceleration and reversal of the loaded thorax, driven by the pelvis through the hip belt connection. Use of the frame in this way may have required less trunk muscle activation and allowed for improved pattern stability.


Asunto(s)
Pelvis/fisiología , Tórax/fisiología , Caminata/fisiología , Soporte de Peso/fisiología , Adolescente , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Imagenología Tridimensional/estadística & datos numéricos , Masculino , Rotación , Torque
18.
J Paediatr Child Health ; 41(11): 564-8, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16398838

RESUMEN

OBJECTIVE: To compare growth of infants fed goat milk infant formula (GMF) or cow milk infant formula (CMF) and to compare tolerability and safety of the two formulas. METHODS: The study was conducted in Auckland, New Zealand. This was a double-blind randomized controlled trial. Newborn term infants were randomized within 72 h of birth to GMF or CMF. Milk formula powder in single serve sachets were reconstituted and fed to infants from trial commencement until age 168 days. No other formula given from randomization until age 168 days. Infant weight, length and head circumference were measured at birth and age 14, 28, 56, 84, 112, 140 and 168 days. Bowel motion frequency and consistency, sleeping and crying patterns and adverse events were also measured. RESULTS: Seventy-two infants were randomized, 36 each to GMF or CMF, with 62 infants completing the intervention. At enrollment the average weight of infants in the GMF group (mean +/- SD) was 3.33 +/- 0.43 kg and in the CMF group 3.43 +/- 0.47 kg; and at study completion 8.07 +/- 0.90 kg (GMF) and 7.87 +/- 0.99 kg (CMF). The difference in average weight gain over the study period for the GMF group versus the CMF group was not significant (+309 g; 95% CI = -49 to +668, P = 0.09). Median daily bowel motion frequency was greater in the GMF group than the CMF group (2.4 vs 1.7, P = 0.01). There were no group differences in bowel motion consistency, duration of crying, ease of settling, or frequency of adverse events. CONCLUSION: Growth of infants fed GMF is not different to that of infants-fed CMF.


Asunto(s)
Bovinos , Cabras , Crecimiento y Desarrollo/fisiología , Fórmulas Infantiles , Leche , Animales , Alimentación con Biberón , Método Doble Ciego , Humanos , Lactante , Recién Nacido , Nueva Zelanda , Estudios Prospectivos
19.
Drug Dev Ind Pharm ; 29(9): 1005-12, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14606664

RESUMEN

Many aqueous suspension corticosteroid nasal sprays become less viscous when shaken and sprayed, then return to a more viscous state after application. This time-dependent, reversible loss of viscosity under shear (e.g., shaking or spraying) can be quantified in the rheological property of thixotropy. The flow properties of 5 corticosteroid nasal sprays were measured over a range of shear rates. The formulations tested included Nasonex, Vancenase AQ, Nasacort AQ, Rhinocort Aqua, and Flonase. The yield stress values, as well as an estimate of thixotropy, were compared by using three different sampling techniques, including one that simulated patient use (shaking for 30 sec, spraying, and immediately transferring the sample to the rheometer). The rheological properties of all products indicated that when initially shaken and dispensed, they flowed more freely, followed by recovery of viscosity that would likely inhibit the suspensions from flowing out of the nasal cavity. Under all three tested conditions, Nasonex exhibited the highest yield stress, the largest apparent initial and final viscosities, and the highest apparent thixotropy. The study protocol that simulated patient-use conditions produced the following rank order of measured thixotropy: Nasonex > Flonase > Vancenase AQ > Rhinocort Aqua > Nasacort AQ. The thixotropy of Nasonex was 3.4 to 21.4 times greater and the final viscosity was 3.2 to 17.4 times greater than the values of the other tested products.


Asunto(s)
Corticoesteroides/química , Agua/química , Administración Intranasal , Corticoesteroides/análisis , Química Farmacéutica , Resistencia al Corte , Suspensiones , Viscosidad
20.
Eur J Clin Nutr ; 57(11): 1498-503, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14576765

RESUMEN

OBJECTIVE: To evaluate the repeatability of a children's food frequency questionnaire (FFQ) by gender, ethnicity, and age group. DESIGN: A 117-item FFQ asking about food intake patterns over the past 4 weeks was developed using food records from 428 children (204 boys and 224 girls) and the reproducibility on average 13 days apart was tested in 130 children (78 boys and 52 girls). Children were recruited using clustered probability sampling (n=103), and a convenience sample of 25 Maori children. SETTING: Children aged 1-14 y from Auckland, Feilding and Shannon, New Zealand. SUBJECTS: There were 71 Maori, 20 Pacific, and 39 Other children. RESULTS: Spearman correlations between the two FFQs ranged from 0.50 for bread to 0.82 for fruit, with a median of 0.76 for spreads and nonmilk drinks, and Cronbach's coefficient alpha's ranged from 0.59 for bread to 0.92 for nonmilk drinks, with a median of 0.85 for mixed meat dishes. There were no significant differences between the two administrations, apart from reporting higher intakes of vegetables and snacks & sweets in the first FFQ. Correlation coefficients tended to be slightly higher in boys than in girls, and in Other ethnic groups compared to Maori and Pacific children. Correlations were slightly higher for the 1-4 y age group, intermediate in the 10-14 y age group, and lowest in the 5-9 y-old age group. CONCLUSIONS: Overall, the FFQ described here shows similar or better repeatability in New Zealand children of all major ethnic groups compared to other child or adolescent FFQs.


Asunto(s)
Dieta/estadística & datos numéricos , Etnicidad/estadística & datos numéricos , Encuestas Nutricionales , Encuestas y Cuestionarios/normas , Adolescente , Factores de Edad , Niño , Preescolar , Análisis por Conglomerados , Comparación Transcultural , Registros de Dieta , Femenino , Humanos , Lactante , Masculino , Nueva Zelanda , Reproducibilidad de los Resultados , Factores Sexuales
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