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1.
Colorectal Dis ; 25(9): 1771-1782, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37553121

RESUMO

AIM: Proximal and distal colorectal cancers (CRCs) exhibit different clinical, molecular and biological patterns. The aim of this study was to determine temporal trends in the age-standardized incidence rates (ASIRs) of proximal and distal CRC following the introduction of the English Bowel Cancer Screening Programme (BCSP) in 2006. METHOD: The National Cancer Registration and Analysis Service database was used to identify incident cases of CRC among adults of screening age (60-74 years) between 2001 and 2017. ASIRs were calculated using the European Standard Population 2013 and incidence trends analysed by anatomical subsite (proximal, caecum to descending colon; distal, sigmoid to rectum), sex and Index of Multiple Deprivation (IMD) quintile using Joinpoint regression software. RESULTS: Between 2001 and 2017, 541 515 incident cases of CRC were diagnosed [236 167 proximal (43.6%) and 305 348 distal (56.4%)]. A marginal reduction in the proximal ASIR was noted from 2008 [annual percentage change (APC) -1.4% (95% CI -2.0% to -0.9%)] compared with a greater reduction in distal ASIR from 2011 to 2014 [APC -6.6% (95% CI -11.5% to -1.5%)] which plateaued thereafter [APC -0.5% (95% CI -3.2% to 2.2%)]. Incidence rates decreased more rapidly in men than women. Adults in IMD quintiles 4-5 experienced the greatest reduction in distal tumours [APC -3.5% (95% CI -4.3% to -2.7%)]. CONCLUSION: Following the introduction of the English BCSP, the incidence of CRC has subsequently reduced among adults of screening age, with this trend being most pronounced in distal tumours and in men. There is also evidence of a reduction in the deprivation gap for distal tumour incidence. Strategies to improve the detection of proximal tumours are warranted.


Assuntos
Neoplasias Colorretais , Masculino , Humanos , Adulto , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Incidência , Detecção Precoce de Câncer , Colo Sigmoide/patologia , Reto/patologia
2.
J Immunol Methods ; 512: 113405, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36496007

RESUMO

Humanised antibodies targeting Crimean-Congo Haemorrhagic virus (CCHFV) are needed for the development and standardisation of serological assays. These assays are needed to address a shortfall in available tests that meet regulatory diagnostic standards and to aid surveillance activities to extend knowledge on the distribution of CCHFV. To generate a humanised monoclonal antibody against CCHFV, we have compared two methods: the traditional mouse hybridoma approach with subsequent sequencing and humanisation of antibodies versus a non-animal alternative using a human combinatorial antibody library (HuCAL). Our results demonstrated that the mouse hybridoma followed by humanisation protocol gave higher affinity antibodies. Whilst not yet able to demonstrate the generation of equivalent humanised antibodies without the use of animals, sequencing data enables the subsequent production of recombinant antibodies, thus providing a reduction in future animal usage for this application. Ultimately, our report provides information on development of a humanised standardised control, which can form an important positive control component of serological assays against CCHFV.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Humanos , Animais , Camundongos , Febre Hemorrágica da Crimeia/diagnóstico , Febre Hemorrágica da Crimeia/epidemiologia , Hibridomas , Anticorpos Antivirais , Imunoglobulina G
3.
Biofabrication ; 15(1)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36321254

RESUMO

We describe the development of a high-throughput bioprinted colorectal cancer (CRC) spheroid platform with high levels of automation, information content, and low cell number requirement. This is achieved via the formulation of a hydrogel bioink with a compressive Young's modulus that is commensurate with that of colonic tissue (1-3 kPa), which supports exponential growth of spheroids from a wide range of CRC cell lines. The resulting spheroids display tight cell-cell junctions, bioink matrix-cell interactions and necrotic hypoxic cores. By combining high content light microscopy imaging and processing with rapid multiwell plate bioprinting, dose-response profiles are generated from CRC spheroids challenged with oxaliplatin (OX) and fluorouracil (5FU), as well as radiotherapy. Bioprinted CRC spheroids are shown to exhibit high levels of chemoresistance relative to cell monolayers, and OX was found to be significantly less effective against tumour spheroids than in monolayer culture, when compared to 5FU.


Assuntos
Bioimpressão , Neoplasias Colorretais , Humanos , Esferoides Celulares , Bioimpressão/métodos , Fluoruracila , Linhagem Celular , Oxaliplatina
4.
BJS Open ; 6(4)2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-36029031

RESUMO

AIMS: Recent data suggest that the incidence of malignant appendiceal tumours is increasing. This study aimed to determine temporal trends in the incidence of malignant appendiceal tumours within England and a possible influence by demographic factors. METHODS: All incident cases of appendiceal tumours in patients aged 20 years and above were identified from the National Cancer Registration and Analysis Service database between 1995 and 2016 using ICD-9/10 codes. Cancers were categorized according to histology. Joinpoint regression analysis was used to investigate changes in age-standardized incidence rates by age, sex, histological subtype and index of multiple deprivation quintiles, based on socioeconomic domains (income, employment, education, health, crime, barriers to housing and services and living environment). Average annual per cent changes (AAPCs) were estimated by performing Monte-Carlo permutation analysis. RESULTS: A total of 7333 tumours were diagnosed and 7056 patients were analysed, comprising 3850 (54.6 per cent) neuroendocrine tumours (NETs), 1892 (26.8 per cent) mucinous adenocarcinomas and 1314 (18.6 per cent) adenocarcinoma (not otherwise specified). The overall incidence of appendiceal tumours increased from 0.3 per 100 000 to 1.6 per 100 000 over the study interval. Incidence rate increases of comparable magnitude were observed across all age groups, but the AAPC was highest among patients aged 20-29 years (15.6 per cent, 95 per cent c.i 12.7-18.6 per cent) and 30-39 years (14.2 per cent, 12.2-16.2 per cent) and lowest among those aged 70-79 years (6.8 per cent, 5.7-8.0 per cent). Similar incidence rate increases were reported across all socioeconomic deprivation quintiles and in both sexes. Analysis by grade of NET showed that grade 1 tumours accounted for 63 per cent between 2010 and 2013, compared with 2 per cent between 2000 and 2003. CONCLUSIONS: The incidence rate of malignant appendiceal tumours has increased significantly since 1995 and is mainly attributed to an increase in NETs. The increased diagnosis of low-grade NETs may in part be due to changes in pathological classification systems.


Assuntos
Adenocarcinoma , Neoplasias do Apêndice , Tumores Neuroendócrinos , Inglaterra , Feminino , Humanos , Incidência , Masculino
5.
DNA Repair (Amst) ; 115: 103331, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35468497

RESUMO

The proto-oncogene BCL-3 is upregulated in a subset of colorectal cancers (CRC), where it has been shown to enhance tumour cell survival. However, although increased expression correlates with poor patient prognosis, the role of BCL-3 in determining therapeutic response remains largely unknown. In this study, we use combined approaches in multiple cell lines and pre-clinical mouse models to investigate the function of BCL-3 in the DNA damage response. We show that suppression of BCL-3 increases γH2AX foci formation and decreases homologous recombination in CRC cells, resulting in reduced RAD51 foci number and increased sensitivity to PARP inhibition. Importantly, a similar phenotype is seen in Bcl3-/- mice, where Bcl3-/- mouse crypts also exhibit sensitivity to DNA damage with increased γH2AX foci compared to wild type mice. Additionally, Apc.Kras-mutant x Bcl3-/- mice are more sensitive to cisplatin chemotherapy compared to wild type mice. Taken together, our results identify BCL-3 as a regulator of the cellular response to DNA damage and suggests that elevated BCL-3 expression, as observed in CRC, could increase resistance of tumour cells to DNA damaging agents including radiotherapy. These findings offer a rationale for targeting BCL-3 in CRC as an adjunct to conventional therapies and suggest that BCL-3 expression in tumours could be a useful biomarker in stratification of rectal cancer patients for neo-adjuvant chemoradiotherapy.


Assuntos
Neoplasias Colorretais , Animais , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Dano ao DNA , Recombinação Homóloga , Humanos , Camundongos
6.
Front Immunol ; 12: 703887, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367162

RESUMO

The only licensed dengue vaccine, Dengvaxia®, increases risk of severe dengue when given to individuals without prior dengue virus (DENV) infection but is protective against future disease in those with prior DENV immunity. The World Health Organization has recommended using rapid diagnostic tests (RDT) to determine history of prior DENV infection and suitability for vaccination. Dengue experts recommend that these assays be highly specific (≥98%) to avoid erroneously vaccinating individuals without prior DENV infection, as well as be sensitive enough (≥95%) to detect individuals with a single prior DENV infection. We evaluated one existing and two newly developed anti-flavivirus RDTs using samples collected >6 months post-infection from individuals in non-endemic and DENV and ZIKV endemic areas. We first evaluated the IgG component of the SD BIOLINE Dengue IgG/IgM RDT, which was developed to assist in confirming acute/recent DENV infections (n=93 samples). When evaluated following the manufacturer's instructions, the SD BIOLINE Dengue RDT had 100% specificity for both non-endemic and endemic samples but low sensitivity for detecting DENV seropositivity (0% non-endemic, 41% endemic). Sensitivity increased (53% non-endemic, 98% endemic) when tests were allowed to run beyond manufacturer recommendations (0.5 up to 3 hours), but specificity decreased in endemic samples (36%). When tests were evaluated using a quantitative reader, optimal specificity could be achieved (≥98%) while still retaining sensitivity at earlier timepoints in non-endemic (44-88%) and endemic samples (31-55%). We next evaluated novel dengue and Zika RDTs developed by Excivion to detect prior DENV or ZIKV infections and reduce cross-flavivirus reactivity (n=207 samples). When evaluated visually, the Excivion Dengue RDT had sensitivity and specificity values of 79%, but when evaluated with a quantitative reader, optimal specificity could be achieved (≥98%) while still maintaining moderate sensitivity (48-75%). The Excivion Zika RDT had high specificity (>98%) and sensitivity (>93%) when evaluated quantitatively, suggesting it may be used alongside dengue RDTs to minimize misclassification due to cross-reactivity. Our findings demonstrate the potential of RDTs to be used for dengue pre-vaccination screening to reduce vaccine-induced priming for severe dengue and show how assay design adaptations as well quantitative evaluation can further improve RDTs for this purpose.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/metabolismo , Dengue , Testes Diagnósticos de Rotina , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Dengue/sangue , Dengue/diagnóstico , Vacinas contra Dengue/administração & dosagem , Vacinas contra Dengue/efeitos adversos , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade
7.
Br J Cancer ; 124(12): 1959-1969, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785874

RESUMO

BACKGROUND: Most colorectal cancers (CRC) arise sporadically from precursor lesions: colonic polyps. Polyp resection prevents progression to CRC. Risk of future polyps is proportional to the number and size of polyps detected at screening, allowing identification of high-risk individuals who may benefit from effective chemoprophylaxis. We aimed to investigate the potential of 5-aminosalicylic acid (5-ASA), a medication used in the treatment of ulcerative colitis, as a possible preventative agent for sporadic CRC. METHODS: Human colorectal adenoma (PC/AA/C1, S/AN/C1 and S/RG/C2), transformed adenoma PC/AA/C1/SB10 and carcinoma cell lines (LS174T and SW620) were treated with 5-ASA. The effect on growth in two- and three-dimensional (3D) culture, ß-catenin transcriptional activity and on cancer stemness properties of the cells were investigated. RESULTS: 5-ASA was shown, in vitro, to inhibit the growth of adenoma cells and suppress ß-catenin transcriptional activity. Downregulation of ß-catenin was found to repress expression of stem cell marker LGR5 (leucine-rich G protein-coupled receptor-5) and functionally suppress stemness in human adenoma and carcinoma cells using 3D models of tumorigenesis. CONCLUSIONS: 5-ASA can suppress the cancer stem phenotype in adenoma-derived cells. Affordable and well-tolerated, 5-ASA is an outstanding candidate as a chemoprophylactic medication to reduce the risk of colorectal polyps and CRC in those at high risk.


Assuntos
Adenoma/patologia , Neoplasias Colorretais/patologia , Mesalamina/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Adenoma/tratamento farmacológico , Adenoma/genética , Adenoma/prevenção & controle , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma/genética , Carcinoma/patologia , Carcinoma/prevenção & controle , Linhagem Celular Tumoral , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Quimioprevenção/métodos , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/prevenção & controle , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesalamina/uso terapêutico , Células-Tronco Neoplásicas/fisiologia , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
8.
Sensors (Basel) ; 21(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33406602

RESUMO

Hearing loss is a disabling condition that increases with age and has been linked to difficulties in walking and increased risk of falls. The purpose of this study is to investigate changes in gait parameters associated with hearing loss in a group of older adults aged 60 or greater. Custom-engineered footwear was used to collect spatiotemporal gait data in an outpatient clinical setting. Multivariable linear regression was used to determine the relationship between spatiotemporal gait parameters and high and low frequency hearing thresholds of the poorer hearing ear, the left ear, and the right ear, respectively, adjusting for age, sex, race/ethnicity, and the Dizziness Handicap Inventory-Screening version score. Worsening high and low frequency hearing thresholds were associated with increased variability in double support period. Effects persisted after adjusting for the effects of age and perceived vestibular disability and were greater for increases in hearing thresholds for the right ear compared to the left ear. These findings illustrate the importance of auditory feedback for balance and coordination and may suggest a right ear advantage for the influence of auditory feedback on gait.


Assuntos
Surdez , Perda Auditiva , Acidentes por Quedas , Idoso , Feminino , Marcha , Perda Auditiva/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Caminhada
9.
Carcinogenesis ; 41(3): 249-256, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31930327

RESUMO

With its identification as a proto-oncogene in chronic lymphocytic leukaemia and central role in regulating NF-κB signalling, it is perhaps not surprising that there have been an increasing number of studies in recent years investigating the role of BCL-3 (B-Cell Chronic Lymphocytic Leukaemia/Lymphoma-3) in a wide range of human cancers. Importantly, this work has begun to shed light on our mechanistic understanding of the function of BCL-3 in tumour promotion and progression. Here, we summarize the current understanding of BCL-3 function in relation to the characteristics or traits associated with tumourigenesis, termed 'Hallmarks of Cancer'. With the focus on colorectal cancer, a major cause of cancer related mortality in the UK, we describe the evidence that potentially explains why increased BCL-3 expression is associated with poor prognosis in colorectal cancer. As well as promoting tumour cell proliferation, survival, invasion and metastasis, a key emerging function of this proto-oncogene is the regulation of the tumour response to inflammation. We suggest that BCL-3 represents an exciting new route for targeting the Hallmarks of Cancer; in particular by limiting the impact of the enabling hallmarks of tumour promoting inflammation and cell plasticity. As BCL-3 has been reported to promote the stem-like potential of cancer cells, we suggest that targeting BCL-3 could increase the tumour response to conventional treatment, reduce the chance of relapse and hence improve the prognosis for cancer patients.


Assuntos
Proteína 3 do Linfoma de Células B/genética , Carcinogênese/genética , Neoplasias Colorretais/genética , Recidiva Local de Neoplasia/genética , Proliferação de Células/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , NF-kappa B/genética , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Prognóstico , Proto-Oncogene Mas , Transdução de Sinais/genética
10.
Curr Issues Mol Biol ; 34: 215-230, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31167962

RESUMO

Over 35 years since it was established to make recombinant proteins, the baculovirus expression vector system continues to develop and improve. Early systems for recombinant virus selection were laborious, but better methods were rapidly devised that enabled non-virologists to use baculovirus vectors successfully in a wide range of applications. These applications include multiple gene expression for complex molecules, production of adeno-associated virus-like particles for gene therapy, the use of baculovirus budded virus for the same purpose, numerous potential human and animal vaccines, and for other therapeutic proteins. A number of products for human and veterinary use are now on the market, which attests to the utility of the systems. Despite these successes, baculovirus vectors essentially remain in a relatively primitive state of development. Many proteins, particularly membrane-bound or secreted products, continue to be difficult to produce. Various research groups are working to identify potential areas of improvement, which if combined into an ideal vector might offer considerable advances to the system. This chapter will review some of the most recent reports and highlight those that might have generic application for recombinant protein synthesis in insect cells. We also summarize parallel developments in host cells used for baculovirus expression and how culture conditions can influence protein production.


Assuntos
Baculoviridae/genética , Expressão Gênica , Engenharia Genética , Vetores Genéticos/genética , Animais , Engenharia Genética/métodos , Humanos , Engenharia de Proteínas , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética
11.
Endocrinology ; 160(11): 2737-2747, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31074796

RESUMO

To study the effects of an analog of the gut-produced hormone peptide YY (PYY3-36), which has increased selectivity for the Y2 receptor; specifically, to record its effects on food intake and on hypothalamic neuropeptide Y/agouti-related peptide (NPY/AgRP) neuron activity. NNC0165-1273, a modified form of the peptide hormone PYY3-36 with potent selectivity at Y2 receptor (>5000-fold over Y1, 1250-fold over Y4, and 650-fold over Y5 receptor), was tested in vivo and in vitro in mouse models. NNC0165-1273 has fivefold lower relative affinity for Y2 compared with PYY3-36, but >250-, 192-, and 400-fold higher selectivity, respectively, for the Y1, Y4, and Y5 receptors. NNC0165-1273 produced a reduction in nighttime feeding at a dose at which PYY3-36 loses efficacy. The normal behavioral satiety sequence observed suggests that NNC0165-1273 is not nauseating and, instead, reduces food intake by producing early satiety. Additionally, NNC0165-1273 blocked ghrelin-induced cFos expression in NPY/AgRP neurons. In vitro electrophysiological recordings showed that, opposite to ghrelin, NNC0165-1273 hyperpolarized NPY/AgRP neurons and reduced action potential frequency. Administration of NNC0165-1273 via subcutaneous osmotic minipump caused a dose-dependent decrease in body weight and fat mass in an obese mouse model. Finally, NNC0165-1273 attenuated the feeding response when NPY/AgRP neurons were activated using ghrelin or more selectively with designer receptors. NNC0165-1273 is nonnauseating and stimulates a satiety response through, at least in part, a direct action on hypothalamic NPY/AgRP neurons. Modification of PYY3-36 to produce compounds with increased affinity to Y2 receptors may be useful as antiobesity therapies in humans.


Assuntos
Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Fragmentos de Peptídeos/química , Peptídeo YY/química , Receptores de Neuropeptídeo Y/agonistas , Resposta de Saciedade/efeitos dos fármacos , Animais , Núcleo Arqueado do Hipotálamo/citologia , Grelina , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Peptídeo YY/farmacologia
12.
Dis Model Mech ; 12(3)2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30792270

RESUMO

To decrease bowel cancer incidence and improve survival, we need to understand the mechanisms that drive tumorigenesis. Recently, B-cell lymphoma 3 (BCL-3; a key regulator of NF-κB signalling) has been recognised as an important oncogenic player in solid tumours. Although reported to be overexpressed in a subset of colorectal cancers (CRCs), the role of BCL-3 expression in colorectal tumorigenesis remains poorly understood. Despite evidence in the literature that BCL-3 may interact with ß-catenin, it is perhaps surprising, given the importance of deregulated Wnt/ß-catenin/T-cell factor (TCF) signalling in colorectal carcinogenesis, that the functional significance of this interaction is not known. Here, we show for the first time that BCL-3 acts as a co-activator of ß-catenin/TCF-mediated transcriptional activity in CRC cell lines and that this interaction is important for Wnt-regulated intestinal stem cell gene expression. We demonstrate that targeting BCL-3 expression (using RNA interference) reduced ß-catenin/TCF-dependent transcription and the expression of intestinal stem cell genes LGR5 and ASCL2 In contrast, the expression of canonical Wnt targets Myc and cyclin D1 remained unchanged. Furthermore, we show that BCL-3 increases the functional stem cell phenotype, as shown by colorectal spheroid and tumoursphere formation in 3D culture conditions. We propose that BCL-3 acts as a driver of the stem cell phenotype in CRC cells, potentially promoting tumour cell plasticity and therapeutic resistance. As recent reports highlight the limitations of directly targeting cancer stem cells (CSCs), we believe that identifying and targeting drivers of stem cell plasticity have significant potential as new therapeutic targets.This article has an associated First Person interview with the first author of the paper.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/metabolismo , Via de Sinalização Wnt , Proteína 3 do Linfoma de Células B , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Fenótipo , Ligação Proteica , Transporte Proteico , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Fatores de Transcrição TCF/metabolismo , Fatores de Transcrição/genética , beta Catenina/metabolismo
13.
Vaccine ; 36(46): 7003-7010, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30309744

RESUMO

African horse sickness is a severe, often fatal, arboviral disease of equids. The control of African horse sickness virus (AHSV) in endemic countries is based currently on the use of live attenuated vaccines despite some biosafety concerns derived from its biological properties. Thus, experimental vaccination platforms have been developed over the years in order to avoid the biosafety concerns associated with the use of attenuated vaccines. Various studies showed that baculovirus-expressed AHSV-VP2 or modified Vaccinia Ankara virus expressing AHSV-VP2 (MVA-VP2) induced virus neutralising antibodies and protective immunity in small animals and horses. AHSV is an antigenically diverse pathogen and immunity against AHS is serotype-specific. Therefore, AHS vaccines for use in endemic countries need to induce an immune response capable of protecting against all existing serotypes. For this reason, current live attenuated vaccines are administered as polyvalent preparations comprising combinations of AHSV attenuated strains of different serotypes. Previous studies have shown that it is possible to induce cross-reactive virus neutralising antibodies against different serotypes of AHSV by using polyvalent vaccines comprising combinations of either different serotype-specific VP2 proteins, or MVA-VP2 viruses. However, these strategies could be difficult to implement if induction of protective immunity is highly dependent on using a two-dose vaccination regime for each serotype the vaccine intends to protect against. In our study, we have tested the protective capacity of MVA-VP2 and baculovirus-expressed VP2 vaccines when a single dose was used. Groups of interferon alpha receptor knock-out mice were inoculated with either MVA-VP2 or baculovirus-expressed VP2 vaccines using one dose or the standard two-dose vaccination regime. After vaccination, all four vaccinated groups were challenged with AHSV and clinical responses, lethality and viraemia compared between the groups. Our results show that complete clinical protection was achieved after a single vaccination with either MVA-VP2 or baculovirus sub-unit VP2 vaccines.


Assuntos
Doença Equina Africana/prevenção & controle , Proteínas do Capsídeo/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Animais , Baculoviridae/genética , Modelos Animais de Doenças , Portadores de Fármacos , Feminino , Vetores Genéticos , Camundongos , Análise de Sobrevida , Resultado do Tratamento , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vaccinia virus/genética , Viremia/prevenção & controle
14.
Viruses ; 10(10)2018 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-30347797

RESUMO

Pancreatic islet transplantation is a promising treatment for type 1 diabetes mellitus offering improved glycaemic control by restoring insulin production. Improved human pancreatic islet isolation has led to higher islet transplantation success. However, as many as 50% of islets are lost after transplantation due to immune responses and cellular injury, gene therapy presents a novel strategy to protect pancreatic islets for improved survival post-transplantation. To date, most of the vectors used in clinical trials and gene therapy studies have been derived from mammalian viruses such as adeno-associated or retrovirus. However, baculovirus BacMam vectors provide an attractive and safe alternative. Here, a novel BacMam was constructed containing a frameshift mutation within fp25, which results in virus stocks with higher infectious titres. This improved in vitro transduction when compared to control BacMams. Additionally, incorporating a truncated vesicular stomatitis virus G protein increased transduction efficacy and production of EGFP and BCL2 in human kidney (HK-2) and pancreatic islet ß cells (EndoC ßH3). Lastly, we have shown that our optimized BacMam vector can deliver and express egfp in intact pancreatic islet cells from human cadaveric donors. These results confirm that BacMam vectors are a viable choice for providing delivery of transgenes to pancreatic islet cells.


Assuntos
Baculoviridae/genética , Diabetes Mellitus Tipo 1/terapia , Terapia Genética/instrumentação , Células Secretoras de Insulina/virologia , Transdução Genética , Baculoviridae/fisiologia , Técnicas de Transferência de Genes , Terapia Genética/métodos , Vetores Genéticos/genética , Vetores Genéticos/fisiologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Ilhotas Pancreáticas/virologia
15.
Curr Protoc Protein Sci ; 91: 5.4.1-5.4.6, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29516481

RESUMO

This unit provides information on the replication cycle of insect baculovirus to provide an understanding of how this virus has been adapted for use as an expression vector for recombinant proteins in insect cells. We provide an overview of the virus structure and its unique bi-phasic replication cycle, which has been exploited in developing the virus as an expression vector. We also review the development of the baculovirus expression vector system (BEVS), from the mid-1980s to the present day in which the BEVS is now an established tool for the production of a range of recombinant proteins and multi-protein complexes including virus-like particles. We describe advances made to the BEVS to allow the rapid and easy production of recombinant viruses and developments to improve protein yield. We finish by describing the application of recombinant BacMam as vectors for the delivery of genes into mammalian and human cells. © 2018 by John Wiley & Sons, Inc.


Assuntos
Baculoviridae/genética , Baculoviridae/metabolismo , Expressão Gênica , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Proteínas Recombinantes/biossíntese , Animais , Humanos , Proteínas Recombinantes/genética
16.
Curr Protoc Protein Sci ; 91: 5.5.1-5.5.22, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29516484

RESUMO

Baculovirus expression systems are well established as an easy and reliable way to produce high quality recombinant proteins. Baculoviruses can also be used to transduce mammalian cells, termed 'BacMam', with considerable potential in biomedical applications. This chapter explains the process of making a recombinant baculovirus, encompassing production of a recombinant virus by homologous recombination in insect cells, followed by amplification and titration of the virus-all steps needed before commencing gene expression and protein production. We also cover the use of small-scale test expression to provide an initial indication of quality and protein yield. Whereas proteins expressed at high levels can be directly scaled up, more challenging proteins may require optimization of cell lines, growth conditions, or harvest times. Scale-up and purification approaches are discussed, focusing on working with large shake cultures and use of the Wave bioreactor. © 2018 by John Wiley & Sons, Inc.


Assuntos
Baculoviridae/genética , Baculoviridae/metabolismo , Reatores Biológicos , Expressão Gênica , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Proteínas Recombinantes/biossíntese , Animais , Humanos , Proteínas Recombinantes/genética
17.
BMJ Open Diabetes Res Care ; 5(1): e000431, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29225893

RESUMO

OBJECTIVE: To explore partial jejunal diversion (PJD) via a side-to-side jejuno-jejunostomy for improved glycemic control in type 2 diabetes mellitus (T2DM). PJD is an anatomy-sparing, technically simple surgery in comparison to the predominate metabolic procedures, Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). Positive results in a rodent model prompted a human proof-of-concept study. RESEARCH DESIGN AND METHODS: Pre-clinically, 71 rats were studied in a model of metabolic dysfunction induced by a high-fat diet; 33 animals undergoing one of two lengths of PJD were compared with 18 undergoing sham, 10 RYGB and 10 jejuno-ileal bypass. Clinically, 15 adult subjects with treated but inadequately controlled T2DM (hemoglobin A1c (HbA1c) of 8.0%-11.0%), body mass index of 27.0-40.0 kg/m2, and C peptide ≥3 ng/mL were studied. Follow-up was at 2 weeks, and 3, 6, 9, and 12 months post-PJD. RESULTS: Pre-clinically, positive impacts with PJD on glucose homeostasis, cholesterol, and body composition versus sham control were demonstrated. Clinically, PJD was performed successfully without serious complications. Twelve months post-surgery, the mean (SD) reduction from baseline in HbA1c was 2.3% (1.3) (p<0.01). CONCLUSIONS: PJD may provide an anatomy sparing, low-risk, intervention for poorly controlled T2DM without significant alteration of the patient's lifestyle. The proof-of-concept study is limited by a small sample size and advanced disease, with 80% of participants on insulin and a mean time since diagnosis of over 10 years. Further study is warranted. TRIAL REGISTRATION NUMBER: NCT02283632; Pre-results.

18.
Otol Neurotol ; 38(10): 1490-1499, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28984811

RESUMO

OBJECTIVE: To evaluate the association between Dizziness Handicap Inventory-Screening version (DHI-S) score and spatiotemporal gait parameters using SoleSound, a newly developed, inexpensive, portable footwear-based gait analysis system. STUDY DESIGN: Cross-sectional. PATIENTS: One hundred eighteen patients recruited from otology clinic. INTERVENTION(S): Subjects completed the DHI-S survey and four uninterrupted walking laps wearing SoleSound instrumented footwear on a hard, flat surface for 100 m. MAIN OUTCOME MEASURE(S): For each subject, mean and coefficient of variation (CV) of stride length, cadence, walking speed, foot-ground clearance, double-support time, swing period, and stance-to-swing were computed by considering 40 strides of steady-state walking within each lap. Linear regression models were employed to study correlations between these variables and DHI-S scores after adjusting for age, sex, and race/ethnicity. RESULTS: Patients with higher DHI-S score took shorter steps and less steps per minute (-0.017 m and -1.1 steps/min per every four-point increase in DHI-S score, p < 0.05) than patients with a lower DHI-S score, with slower walking speed (-0.025 m/s per every four-point increase in DHI-S score, p < 0.01). Additionally, patients with higher DHI-S scores showed larger variability in all analyzed temporal parameters (+0.1% for CV of cadence, +0.5% for CV of double support period, +0.2% for CV of swing period, and +0.4% for CV of stance-to-swing, per every four-point increase in DHI-S score, p < 0.01). CONCLUSION: SoleSound was effective in measuring a wide range of gait parameters. Patients' self-perception of vestibular handicap, as assessed with DHI-S, is associated with deterioration in measurable gait parameters independent of age.


Assuntos
Tontura/fisiopatologia , Marcha/fisiologia , Equilíbrio Postural/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Avaliação da Deficiência , Tontura/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Testes de Função Vestibular , Vestíbulo do Labirinto/fisiologia
19.
Drug Test Anal ; 9(9): 1363-1371, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28407446

RESUMO

Acadesine, 5-aminoimidazole-4-carboxamide-1-ß-D-ribofuranoside, commonly known as AICAR, is a naturally occurring adenosine monophosphate-activated protein kinase (AMPK) activator in many mammals, including humans and horses. AICAR has attracted considerable attention recently in the field of doping control because of a study showing the enhancement of endurance performance in unexercised or untrained mice, resulting in the term 'exercise pill'. Its use has been classified as gene doping by the World Anti-Doping Agency (WADA), and since it is endogenous, it may only be possible to control deliberate administration of AICAR to racehorses after establishment of an appropriate threshold. Herein we report our studies of AICAR in post-race equine urine and plasma samples including statistical studies of AICAR concentrations determined from 1,470 urine samples collected from thoroughbreds and standardbreds and analyzed in Australia, France, and Hong Kong. Quantification methods in equine urine and plasma using liquid chromatography-mass spectrometry were developed by the laboratories in each country. An exchange of spiked urine and plasma samples between the three countries was conducted, confirming no significant differences in the methods. However, the concentration of AICAR in plasma was found to increase upon haemolysis of whole blood samples, impeding the establishment of a suitable threshold in equine plasma. A possible urine screening cut-off at 600 ng/mL for the control of AICAR in racehorses could be considered for adoption. Application of the proposed screening cut-off to urine samples collected after intravenous administration of a small dose (2 g) of AICAR to a mare yielded a short detection time of approximately 4.5 h. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Dopagem Esportivo/prevenção & controle , Ribonucleosídeos/análise , Ribonucleotídeos/análise , Espectrometria de Massas em Tandem/métodos , Aminoimidazol Carboxamida/análise , Aminoimidazol Carboxamida/química , Aminoimidazol Carboxamida/metabolismo , Animais , Austrália , Cromatografia Líquida , Cavalos , Humanos , Ribonucleosídeos/química , Ribonucleosídeos/metabolismo , Ribonucleotídeos/química , Ribonucleotídeos/metabolismo , Urinálise
20.
Cell Metab ; 25(4): 927-934.e3, 2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28325479

RESUMO

Glucagon-like peptide 1 (GLP-1) is necessary for normal gluco-regulation, and it has been widely presumed that this function reflects the actions of GLP-1 released from enteroendocrine L cells. To test the relative importance of intestinal versus pancreatic sources of GLP-1 for physiological regulation of glucose, we administered a GLP-1R antagonist, exendin-[9-39] (Ex9), to mice with tissue-specific reactivation of the preproglucagon gene (Gcg). Ex9 impaired glucose tolerance in wild-type mice but had no impact on Gcg-null or GLP-1R KO mice, suggesting that Ex9 is a true and specific GLP-1R antagonist. Unexpectedly, Ex-9 had no effect on blood glucose in mice with restoration of intestinal Gcg. In contrast, pancreatic reactivation of Gcg fully restored the effect of Ex9 to impair both oral and i.p. glucose tolerance. These findings suggest an alternative model whereby islet GLP-1 also plays an important role in regulating glucose homeostasis.


Assuntos
Glucose/metabolismo , Homeostase , Pâncreas/metabolismo , Proglucagon/metabolismo , Administração Oral , Animais , Feminino , Trato Gastrointestinal/metabolismo , Regulação da Expressão Gênica , Marcação de Genes , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Teste de Tolerância a Glucose , Injeções Intraperitoneais , Masculino , Camundongos Endogâmicos C57BL , Especificidade de Órgãos , Fenótipo , Proglucagon/genética , Reprodutibilidade dos Testes
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