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1.
Nature ; 589(7841): 211-213, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33442039

RESUMO

Soft γ-ray repeaters exhibit bursting emission in hard X-rays and soft γ-rays. During the active phase, they emit random short (milliseconds to several seconds long), hard-X-ray bursts, with peak luminosities1 of 1036 to 1043 erg per second. Occasionally, a giant flare with an energy of around 1044 to 1046 erg is emitted2. These phenomena are thought to arise from neutron stars with extremely high magnetic fields (1014 to 1015 gauss), called magnetars1,3,4. A portion of the second-long initial pulse of a giant flare in some respects mimics short γ-ray bursts5,6, which have recently been identified as resulting from the merger of two neutron stars accompanied by gravitational-wave emission7. Two γ-ray bursts, GRB 051103 and GRB 070201, have been associated with giant flares2,8-11. Here we report observations of the γ-ray burst GRB 200415A, which we localized to a 20-square-arcmin region of the starburst galaxy NGC 253, located about 3.5 million parsecs away. The burst had a sharp, millisecond-scale hard spectrum in the initial pulse, which was followed by steady fading and softening over 0.2 seconds. The energy released (roughly 1.3 × 1046 erg) is similar to that of the superflare5,12,13 from the Galactic soft γ-ray repeater SGR 1806-20 (roughly 2.3 × 1046 erg). We argue that GRB 200415A is a giant flare from a magnetar in NGC 253.

2.
N Z Vet J ; 69(5): 255-266, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33969809

RESUMO

Over the last 50 years, there have been major advances in knowledge and technology regarding genetic diseases, and the subsequent ability to control them in a cost-effective manner. This review traces these advances through research into genetic diseases of animals at Massey University (Palmerston North, NZ), and briefly discusses the disorders investigated during that time, with additional detail for disorders of major importance such as bovine α-mannosidosis, ovine ceroid-lipofuscinosis, canine mucopolysaccharidosis IIIA and feline hyperchylomicronaemia. The overall research has made a significant contribution to veterinary medicine, has provided new biological knowledge and advanced our understanding of similar disorders in human patients, including testing various specific therapies prior to human clinical trials.


Assuntos
Doenças do Gato , Doenças dos Bovinos , Doenças do Cão , Lipofuscinoses Ceroides Neuronais , Doenças dos Ovinos , Animais , Gatos , Bovinos , Cães , Humanos , Lipofuscinoses Ceroides Neuronais/veterinária , Ovinos , Universidades
3.
Br J Cancer ; 122(12): 1760-1768, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32350413

RESUMO

BACKGROUND: Nab-paclitaxel plus gemcitabine (nabP+gemcitabine) offers modest survival gains for patients with metastatic pancreatic ductal adenocarcinoma (PDAC). Sequential scheduling of nabP+gemcitabine in a PDAC mouse model improved efficacy; this hypothesis was tested in a clinical trial. METHODS: Patients with previously untreated metastatic PDAC were randomised to receive nabP+gemcitabine administered either concomitantly on the same day, or sequentially, with gemcitabine administered 24 h after nabP. The primary outcome measure was progression-free survival (PFS). Secondary outcome measures were objective response rate (ORR), overall survival (OS), safety, quality of life (QoL) and predictive biomarkers. RESULTS: In total, 71 patients received sequential (SEQ) and 75 concomitant (CON) treatment. Six-month PFS was 46% with SEQ and 32% with CON scheduling. Median PFS (5.6 versus 4.0 months, hazard ratio [HR] 0.67, 95% confidence interval [95% CI] 0.47-0.95, p = 0.022) and ORR (52% versus 31%, p = 0.023) favoured the SEQ arm; median OS was 10.2 versus 8.2 months (HR 0.93, 95% CI 0.65-1.33, p = 0.70). CTCAE Grade ≥3 neutropaenia incidence doubled with SEQ therapy but was not detrimental to QoL. Strongly positive tumour epithelial cytidine deaminase (CDA) expression favoured benefit from SEQ therapy (PFS HR 0.31, 95% CI 0.13-0.70). CONCLUSIONS: SEQ delivery of nabP+gemcitabine improved PFS and ORR, with manageable toxicity, but did not significantly improve OS. CLINICAL TRIAL REGISTRATION: ISRCTN71070888; ClinialTrials.gov (NCT03529175).


Assuntos
Albuminas/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Desoxicitidina/análogos & derivados , Paclitaxel/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/mortalidade , Desoxicitidina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Intervalo Livre de Progressão , Gencitabina , Neoplasias Pancreáticas
4.
Nature ; 507(7491): 229-32, 2014 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-24598547

RESUMO

One of the most striking examples of sexual dimorphism is sex-limited mimicry in butterflies, a phenomenon in which one sex--usually the female--mimics a toxic model species, whereas the other sex displays a different wing pattern. Sex-limited mimicry is phylogenetically widespread in the swallowtail butterfly genus Papilio, in which it is often associated with female mimetic polymorphism. In multiple polymorphic species, the entire wing pattern phenotype is controlled by a single Mendelian 'supergene'. Although theoretical work has explored the evolutionary dynamics of supergene mimicry, there are almost no empirical data that address the critical issue of what a mimicry supergene actually is at a functional level. Using an integrative approach combining genetic and association mapping, transcriptome and genome sequencing, and gene expression analyses, we show that a single gene, doublesex, controls supergene mimicry in Papilio polytes. This is in contrast to the long-held view that supergenes are likely to be controlled by a tightly linked cluster of loci. Analysis of gene expression and DNA sequence variation indicates that isoform expression differences contribute to the functional differences between dsx mimicry alleles, and protein sequence evolution may also have a role. Our results combine elements from different hypotheses for the identity of supergenes, showing that a single gene can switch the entire wing pattern among mimicry phenotypes but may require multiple, tightly linked mutations to do so.


Assuntos
Borboletas/genética , Borboletas/fisiologia , Proteínas de Ligação a DNA , Proteínas de Drosophila , Genes de Insetos , Mimetismo Molecular/genética , Caracteres Sexuais , Alelos , Animais , Borboletas/anatomia & histologia , Evolução Molecular , Feminino , Regulação da Expressão Gênica , Masculino , Mimetismo Molecular/fisiologia , Dados de Sequência Molecular , Mutação/genética , Fenótipo , Pigmentação/genética , Pigmentação/fisiologia , Polimorfismo Genético/genética , Transcriptoma/genética , Asas de Animais/fisiologia
5.
Br J Cancer ; 118(9): 1162-1168, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29563636

RESUMO

BACKGROUND: This multicentre, open-label, phase-I/randomised phase-II trial evaluated safety, pharmacokinetics, maximum-tolerated-dose (MTD) per dose-limiting toxicities (DLTs), and efficacy of nintedanib vs. sorafenib in European patients with unresectable advanced hepatocellular carcinoma (aHCC). METHODS: Phase I: Patients were stratified into two groups per baseline aminotransferase/alanine aminotransferase and Child-Pugh score; MTD was determined. Phase II: Patients were randomised 2:1 to nintedanib (MTD) or sorafenib (400-mg bid) in 28-day cycles until intolerance or disease progression. Time-to-progression (TTP, primary endpoint), overall survival (OS) and progression-free survival (PFS) were determined. RESULTS: Phase-I: no DLTs observed; nintedanib MTD in both groups was 200 mg bid. Phase-II: patients (N = 93) were randomised to nintedanib (n = 62) or sorafenib (n = 31); TTP was 5.5 vs. 4.6 months (HR = 1.44 [95% CI, 0.81-2.57]), OS was 11.9 vs. 11.4 months (HR = 0.88 [95% CI, 0.52-1.47]), PFS was 5.3 vs. 3.9 months (HR = 1.35 [95% CI, 0.78-2.34]), respectively (all medians). Dose intensity and tolerability favoured nintedanib. Fewer patients on nintedanib (87.1%) vs. sorafenib (96.8%) had drug-related adverse events (AEs) or grade ≥ 3 AEs (67.7% vs. 90.3%), but more patients on nintedanib (28 [45.2%]) had AEs leading to drug discontinuation than did those on sorafenib (7 [22.6%]). CONCLUSIONS: Nintedanib may have similar efficacy to sorafenib in aHCC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Indóis , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Progressão da Doença , Intervalo Livre de Doença , Europa (Continente)/epidemiologia , Feminino , Humanos , Indóis/administração & dosagem , Indóis/efeitos adversos , Indóis/farmacocinética , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Sorafenibe/administração & dosagem , Sorafenibe/efeitos adversos , Sorafenibe/farmacocinética , Resultado do Tratamento
6.
Br J Cancer ; 118(7): 947-954, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29515256

RESUMO

BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) tumour expression may provide added value to human equilibrative nucleoside transporter-1 (hENT1) tumour expression in predicting survival following pyrimidine-based adjuvant chemotherapy. METHODS: DPD and hENT1 immunohistochemistry and scoring was completed on tumour cores from 238 patients with pancreatic cancer in the ESPAC-3(v2) trial, randomised to either postoperative gemcitabine or 5-fluorouracil/folinic acid (5FU/FA). RESULTS: DPD tumour expression was associated with reduced overall survival (hazard ratio, HR = 1.73 [95% confidence interval, CI = 1.21-2.49], p = 0.003). This was significant in the 5FU/FA arm (HR = 2.07 [95% CI = 1.22-3.53], p = 0.007), but not in the gemcitabine arm (HR = 1.47 [0.91-3.37], p = 0.119). High hENT1 tumour expression was associated with increased survival in gemcitabine treated (HR = 0.56 [0.38-0.82], p = 0.003) but not in 5FU/FA treated patients (HR = 1.19 [0.80-1.78], p = 0.390). In patients with low hENT1 tumour expression, high DPD tumour expression was associated with a worse median [95% CI] survival in the 5FU/FA arm (9.7 [5.3-30.4] vs 29.2 [19.5-41.9] months, p = 0.002) but not in the gemcitabine arm (14.0 [9.1-15.7] vs. 18.0 [7.6-15.3] months, p = 1.000). The interaction of treatment arm and DPD expression was not significant (p = 0.303), but the interaction of treatment arm and hENT1 expression was (p = 0.009). CONCLUSION: DPD tumour expression was a negative prognostic biomarker. Together with tumour expression of hENT1, DPD tumour expression defined patient subgroups that might benefit from either postoperative 5FU/FA or gemcitabine.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Transportador Equilibrativo 1 de Nucleosídeo/metabolismo , Neoplasias Pancreáticas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidade , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Fluoruracila/administração & dosagem , Humanos , Imuno-Histoquímica , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidade , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Análise Serial de Tecidos , Gencitabina
7.
Br J Cancer ; 118(8): 1084-1088, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29523831

RESUMO

BACKGROUND: Deoxycytidylate deaminase (DCTD) and ribonucleotide reductase subunit M1 (RRM1) are potential prognostic and predictive biomarkers for pyrimidine-based chemotherapy in pancreatic adenocarcinoma. METHODS: Immunohistochemical staining of DCTD and RRM1 was performed on tissue microarrays representing tumour samples from 303 patients in European Study Group for Pancreatic Cancer (ESPAC)-randomised adjuvant trials following pancreatic resection, 272 of whom had received gemcitabine or 5-fluorouracil with folinic acid in ESPAC-3(v2), and 31 patients from the combined ESPAC-3(v1) and ESPAC-1 post-operative pure observational groups. RESULTS: Neither log-rank testing on dichotomised strata or Cox proportional hazard regression showed any relationship of DCTD or RRM1 expression levels to survival overall or by treatment group. CONCLUSIONS: Expression of either DCTD or RRM1 was not prognostic or predictive in patients with pancreatic adenocarcinoma who had had post-operative chemotherapy with either gemcitabine or 5-fluorouracil with folinic acid.


Assuntos
Adenocarcinoma/tratamento farmacológico , Biomarcadores Tumorais/metabolismo , DCMP Desaminase/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Supressoras de Tumor/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Quimioterapia Adjuvante , Intervalo Livre de Doença , Humanos , Imuno-Histoquímica , Pancreatectomia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Ribonucleosídeo Difosfato Redutase , Análise Serial de Tecidos
8.
Clin Exp Immunol ; 187(1): 6-15, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27529161

RESUMO

The immune system undergoes age-associated changes known as immunosenescence, resulting in increased susceptibility to infections, cancers and autoimmunity in the aged. The basis of our understanding of immunosenescence has been derived primarily from studies examining intrinsic defects within many of the cells of the immune system. While these studies have provided insight into the mechanisms of immunosenescence, a picture is now emerging that the stromal microenvironment within lymphoid organs also contributes significantly to the age-associated decline of immune function. These extrinsic defects appear to impact the functional activity of immune cells and may offer a potential target to recover immune activity. Indeed, rejuvenation studies which have targeted the stromal niche have restored immune function in aged successfully, highlighting the impact of the microenvironment towards the aetiology of immunosenescence.


Assuntos
Envelhecimento/imunologia , Microambiente Celular/imunologia , Sistema Imunitário , Imunossenescência , Células Estromais/imunologia , Animais , Humanos , Regeneração/imunologia
9.
Br J Surg ; 104(4): 418-425, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27861766

RESUMO

BACKGROUND: Cholangiocarcinoma is a rare cancer with a poor prognosis. Radical surgical resection is the only option for curative treatment. Optimal determination of resectability is required so that patients can be stratified into operative or chemotherapeutic treatment cohorts in an accurate and time-efficient manner. Staging laparoscopy is utilized to determine the presence of radiologically occult disease that would preclude further surgical treatment. The aim of this study was to analyse the utility of staging laparoscopy in a contemporary cohort of patients with perihilar cholangiocarcinoma. METHODS: Patients diagnosed with potentially resectable perihilar cholangiocarcinoma between January 2010 and April 2015 were analysed retrospectively from a prospective database linked to UK Hospital Episode Statistics data. Patients with distal cholangiocarcinoma and gallbladder cancer were excluded from analysis. RESULTS: A total of 431 patients with perihilar cholangiocarcinoma were referred for assessment of potential resection at a supraregional referral centre. Some 116 patients with potentially resectable disease subsequently underwent surgical assessment. The cohort demonstrated an all-cause yield of staging laparoscopy for unresectable disease of 27·2 per cent (31 of 114). The sensitivity for detection of peritoneal disease was 71 per cent (15 of 21; P < 0·001). The accuracy for all-cause non-resection for staging laparoscopy was 66 per cent (31 of 47) with a positive predictive value of progress to resection of 81 per cent (69 of 85). Neither the Bismuth-Corlette nor the Memorial Sloan Kettering Cancer Center preoperative scoring system was contingent with cause of unresectability at staging laparoscopy (P = 0·462 and P = 0·280 respectively). CONCLUSION: In the present cohort, staging laparoscopy proved useful in determining the presence of radiologically occult metastatic disease in perihilar cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Tumor de Klatskin/patologia , Laparoscopia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/cirurgia , Feminino , Humanos , Tumor de Klatskin/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Estudos Retrospectivos
10.
Br J Surg ; 104(4): 328-336, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28199010

RESUMO

BACKGROUND: Human equilibrative nucleoside transporters (hENTs) are transmembranous proteins that facilitate the uptake of nucleosides and nucleoside analogues, such as gemcitabine, into the cell. The abundance of hENT1 transporters in resected pancreatic ductal adenocarcinoma (PDAC) might make hENT1 a potential biomarker of response to adjuvant chemotherapy. The aim of this study was to see whether hENT1 expression, as determined by immunohistochemistry, was a suitable predictive marker for subsequent treatment with gemcitabine-based adjuvant chemotherapy. METHODS: A systematic review was performed, searching databases from January 1997 to January 2016. Articles pertaining to hENT1 immunohistochemical analysis in resected PDAC specimens from patients who subsequently underwent adjuvant gemcitabine-based chemotherapy were identified. Eligible studies were required to contain survival data, reporting specifically overall survival (OS) and disease-free survival (DFS) with associated hazard ratios (HRs) stratified by hENT1 status. RESULTS: Of 42 articles reviewed, eight were suitable for review, with seven selected for quantitative meta-analysis. The total number of patients included in the meta-analysis was 770 (405 hENT1-negative, 365 hENT1-positive). Immunohistochemically detected hENT1 expression was significantly associated with both prolonged DFS (HR 0·58, 95 per cent c.i. 0·42 to 0·79) and OS (HR 0·52, 0·38 to 0·72) in patients receiving adjuvant gemcitabine but not those having fluoropyrimidine-based adjuvant therapy. CONCLUSION: Expression of hENT1 is a suitable prognostic biomarker in patients undergoing adjuvant gemcitabine-based chemotherapy.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Desoxicitidina/análogos & derivados , Transportador Equilibrativo 1 de Nucleosídeo/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidade , Quimioterapia Adjuvante , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Humanos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidade , Prognóstico , Gencitabina
11.
Gene Ther ; 23(10): 743-752, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27367841

RESUMO

Pompe disease (glycogen storage disease type II (GSD-II)) is a myopathy caused by a genetic deficiency of acid α-glucosidase (GAA) leading to lysosomal glycogen accumulation causing muscle weakness, respiratory insufficiency and death. We previously demonstrated in GSD-II mice that a single injection of a helper-dependent adenovirus (HD-Ad) expressing GAA resulted in at least 300 days of liver secretion of GAA, correction of the glycogen storage in cardiac and skeletal muscles and improved muscle strength. Recent reports suggest that gene therapy modeling for lysososomal storage diseases in mice fails to predict outcomes in larger animal models. We therefore evaluated an HD-Ad expressing GAA in non-human primates. The baboons not only tolerated the procedure well, but the results also confirmed that a single dose of the HD-Ad allowed the livers of the treated animals to express and secrete large amounts of GAA for at least 6 months, at levels similar to those achieved in mice. Moreover, we detected liver-derived GAA in the heart, diaphragm and skeletal muscles of the treated animals for the duration of the study at levels that corrected glycogen accumulation in mice. This work validates our proof-of-concept studies in mice, and justifies future efforts using Ad-based vectors in Pompe disease patients.


Assuntos
Adenoviridae/genética , Terapia Genética/métodos , Doença de Depósito de Glicogênio Tipo II/terapia , Fígado/metabolismo , alfa-Glucosidases/genética , Animais , Células Cultivadas , Diafragma/metabolismo , Terapia Genética/efeitos adversos , Vetores Genéticos/efeitos adversos , Vetores Genéticos/genética , Vírus Auxiliares/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Papio , alfa-Glucosidases/metabolismo
12.
Clin Exp Allergy ; 46(2): 308-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26250967

RESUMO

BACKGROUND: Egg allergy is a leading cause of food allergy in young infants; however, little is known about early allergen-specific T-cell responses which predate the presentation of egg allergy, and if these are altered by early egg exposure. OBJECTIVE: To investigate the early T-cell responses to multiple egg proteins in relation to patterns of egg exposure and subsequent IgE-mediated egg allergy. METHODS: Egg-specific T-cell cytokine responses (IL-5, IL-13, IL-10, IFNγ and TNFα) to ovomucoid (OM), ovalbumin (OVA), conalbumin (CON) and lysozyme (LYS) were measured in infants with eczema at 4 months of age (n = 40), before randomization to receive 'early egg' or a placebo as part of a randomized controlled trial (Australian New Zealand Clinical Trials Registry number 12609000415202) and at 12 months of age (n = 58), when IgE-mediated egg allergy was assessed by skin prick test and food challenge. RESULTS: In 4-month-old infants, who had not directly ingested egg, those who subsequently developed egg allergy already had significantly higher Th2 cytokine responses to multiple egg allergens, particularly elevated IL-13 responses to OVA (P = 0.004), OM (P = 0.012) and LYS (P = 0.003) and elevated IL-5 to the same antigens (P = 0.031, 0.04 and 0.003, respectively). IL-13 responses (to OVA and LYS) and IL-5 responses (to LYS) at 4 months significantly predicted egg allergy at 12 months. All responses significantly declined with age in the egg-allergic infants, and this did not appear to be modified by 'early' introduction of egg. CONCLUSIONS & CLINICAL RELEVANCE: Elevated egg-specific Th2 cytokine responses were established prior to egg ingestion at 4 months and were not significantly altered by introduction of egg. Th2 responses at 4 months of age predicted egg allergy at 12 months, suggesting that this could be used as a biomarker to select infants for early prevention and management strategies.


Assuntos
Dermatite Atópica/imunologia , Hipersensibilidade a Ovo/imunologia , Proteínas do Ovo/imunologia , Interleucina-13/imunologia , Interleucina-5/imunologia , Dessensibilização Imunológica , Feminino , Humanos , Lactente , Masculino , Células Th2/imunologia
13.
Clin Exp Allergy ; 46(12): 1605-1613, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27562481

RESUMO

BACKGROUND: There is limited understanding of how maternal diet affects breastmilk food allergen concentrations, and whether exposure to allergens through this route influences the development of infant oral tolerance or sensitization. OBJECTIVE: To investigate how maternal dietary egg ingestion during early lactation influences egg protein (ovalbumin) levels detected in human breastmilk. METHODS: In a randomized controlled trial, women were allocated to a dietary group for the first six weeks of lactation: high-egg diet (> 4 eggs per week), low-egg diet (one-three eggs per week) or an egg-free diet. Breastmilk samples were collected at 2, 4 and 6 weeks of lactation for the measurement of ovalbumin. The permeability of the mammary epithelium was assessed by measuring the breastmilk sodium : potassium ratio. Egg-specific IgE and IgG4 were measured in infant plasma at 6 weeks, and prior to the introduction of egg in solids at 16 weeks. RESULTS: Average maternal egg ingestion was associated with breastmilk ovalbumin concentration. Specifically, for each additional egg ingested per week, there was an average 25% increase in ovalbumin concentration (95% CI: 5-48%, P = 0.01). Breastmilk ovalbumin concentrations were significantly higher in the 'high-egg' group (> 4 eggs per week) compared with the 'egg-free' group (P = 0.04). However, one-third of women had no breastmilk ovalbumin detected. No detectable associations were found between mammary epithelium permeability and breastmilk ovalbumin concentrations. Infant plasma egg-specific IgG4 levels were also positively associated with maternal egg ingestion, with an average 22% (95% CI: 3-45%) increase in infant egg-specific IgG4 levels per additional egg consumed per week (P = 0.02). CONCLUSIONS AND CLINICAL RELEVANCE: Increased maternal egg ingestion is associated with increased breastmilk ovalbumin, and markers of immune tolerance in infants. These results highlight the potential for maternal diet to benefit infant oral tolerance development during lactation.


Assuntos
Alérgenos/imunologia , Dieta , Ovos , Hipersensibilidade Alimentar/epidemiologia , Lactação , Leite Humano/imunologia , Ovalbumina/imunologia , Adulto , Animais , Especificidade de Anticorpos , Aleitamento Materno/efeitos adversos , Dieta/efeitos adversos , Ovos/efeitos adversos , Feminino , Hipersensibilidade Alimentar/etiologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lactente , Recém-Nascido , Masculino , Gravidez , Fatores de Risco
14.
Br J Surg ; 103(5): 504-12, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26864728

RESUMO

BACKGROUND: Patients with low fitness as assessed by cardiopulmonary exercise testing (CPET) have higher mortality and morbidity after surgery. Preoperative exercise intervention, or prehabilitation, has been suggested as a method to improve CPET values and outcomes. This trial sought to assess the capacity of a 4-week supervised exercise programme to improve fitness before liver resection for colorectal liver metastasis. METHODS: This was a randomized clinical trial assessing the effect of a 4-week (12 sessions) high-intensity cycle, interval training programme in patients undergoing elective liver resection for colorectal liver metastases. The primary endpoint was oxygen uptake at the anaerobic threshold. Secondary endpoints included other CPET values and preoperative quality of life (QoL) assessed using the SF-36®. RESULTS: Thirty-eight patients were randomized (20 to prehabilitation, 18 to standard care), and 35 (25 men and 10 women) completed both preoperative assessments and were analysed. The median age was 62 (i.q.r. 54-69) years, and there were no differences in baseline characteristics between the two groups. Prehabilitation led to improvements in preoperative oxygen uptake at anaerobic threshold (+1·5 (95 per cent c.i. 0·2 to 2·9) ml per kg per min) and peak exercise (+2·0 (0·0 to 4·0) ml per kg per min). The oxygen pulse (oxygen uptake per heart beat) at the anaerobic threshold improved (+0·9 (0·0 to 1·8) ml/beat), and a higher peak work rate (+13 (4 to 22) W) was achieved. This was associated with improved preoperative QoL, with the overall SF-36® score increasing by 11 (95 per cent c.i. 1 to 21) (P = 0·028) and the overall SF-36® mental health score by 11 (1 to 22) (P = 0·037). CONCLUSION: A 4-week prehabilitation programme can deliver improvements in CPET scores and QoL before liver resection. This may impact on perioperative outcome. REGISTRATION NUMBER: NCT01523353 (https://clinicaltrials.gov).


Assuntos
Terapia por Exercício/métodos , Hepatectomia , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios/métodos , Idoso , Limiar Anaeróbio , Neoplasias Colorretais/patologia , Procedimentos Cirúrgicos Eletivos , Teste de Esforço , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Aptidão Física , Qualidade de Vida , Método Simples-Cego , Resultado do Tratamento
16.
J Physiol ; 593(11): 2447-58, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25809342

RESUMO

KEY POINTS: Patients with transposition of the great arteries (TGA) and systemic right ventricles have premature congestive heart failure; there is also a growing concern that athletes who perform extraordinary endurance exercise may injure the right ventricle. Therefore we felt it essential to determine whether exercise training might injure a systemic right ventricle which is loaded with every heartbeat. Previous studies have shown that short term exercise training is feasible in TGA patients, but its effect on ventricular function is unclear. We demonstrate that systemic right ventricular function is preserved (and may be improved) in TGA patients with exercise training programmes that are typical of recreational and sports participation, with no evidence of injury on biomarker assessment. Stroke volume reserve during exercise correlates with exercise training response in our TGA patients, identifying this as a marker of a systemic right ventricle (SRV) that may most tolerate (and possibly even be improved by) exercise training. ABSTRACT: We aimed to assess the haemodynamic effects of exercise training in transposition of the great arteries (TGA) patients with systemic right ventricles (SRVs). TGA patients have limited exercise tolerance and early mortality due to systemic (right) ventricular failure. Whether exercise training enhances or injures the SRV is unclear. Fourteen asymptomatic patients (34 ± 10 years) with TGA and SRV were enrolled in a 12 week exercise training programme (moderate and high-intensity workouts). Controls were matched on age, gender, BMI and physical activity. Exercise testing pre- and post- training included: (a) submaximal and peak; (b) prolonged (60 min) submaximal endurance and (c) high-intensity intervals. Oxygen uptake (V̇O2; Douglas bag technique), cardiac output (Q̇c, foreign-gas rebreathing), ventricular function (echocardiography and cardiac MRI) and serum biomarkers were assessed. TGA patients had lower peak V̇O2, Q̇c, and stroke volume (SV), a blunted Q̇c/V̇O2 slope, and diminished SV response to exercise (SV increase from rest: TGA = 15.2%, controls = 68.9%, P < 0.001) compared with controls. After training, TGA patients increased peak V̇O2 by 6 ± 8.5%, similar to controls (interaction P = 0.24). The magnitude of SV reserve on initial testing correlated with Q̇c training response (r = 0.58, P = 0.047), though overall, no change in peak Q̇c was observed. High-sensitivity troponin T (hs-TnT) and N-terminal prohormone of brain naturetic peptide (NT pro-BNP) were low and did not change with acute exercise or after training. Our data show that TGA patients with SRVs in this study safely participated in exercise training and improved peak V̇O2. Neither prolonged submaximal exercise, nor high-intensity intervals, nor short-term exercise training seem to injure the systemic right ventricle.


Assuntos
Exercício Físico/fisiologia , Ventrículos do Coração/fisiopatologia , Transposição dos Grandes Vasos/fisiopatologia , Função Ventricular Direita/fisiologia , Adulto , Débito Cardíaco , Ecocardiografia , Teste de Esforço , Feminino , Humanos , Masculino , Volume Sistólico
17.
Gene Ther ; 22(10): 781-92, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26018935

RESUMO

Linker for activation of T cells (LAT) is critical for the propagation of T-cell signals upon T-cell receptor (TCR) activation. Previous studies demonstrated that substitution of LAT lysines with arginines (2KR LAT) resulted in decreased LAT ubiquitination and elevated T-cell signaling, indicating that LAT ubiquitination is a molecular checkpoint for attenuation of T-cell signaling. To investigate the role of LAT ubiquitination in vivo, we have generated transgenic mice expressing WT and ubiquitin-defective 2KR LAT. On TCR stimulation of T cells from these mice, proximal signaling and cytokine production was elevated in 2KR versus wild-type (WT) LAT mice. Enhanced cytolytic activity as well as T-helper responses were observed on LAT expression, which were further elevated by 2KR LAT expression. Despite greater T-effector function, WT or 2KR LAT expression did not have any effect on clearance of certain pathogens or tumors. Our data support the model that lack of tumor clearance is due to increased differentiation and acquisition of effector phenotype that is associated with suboptimal immunity in an immunotherapy model. Thus, our data further reinforce the role of LAT ubiquitination in TCR signaling and uncovers a novel role for LAT in driving T-cell differentiation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Ativação Linfocitária , Linfócitos/imunologia , Proteínas de Membrana/genética , Fosfoproteínas/genética , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Substituição de Aminoácidos , Animais , Diferenciação Celular/genética , Ativação Linfocitária/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos Transgênicos , Fosfoproteínas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Ubiquitinação
18.
Clin Exp Allergy ; 45(1): 220-31, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25378203

RESUMO

BACKGROUND: Vitamin D (25[OH]D3) status in early life has been linked to the risk of allergic disease in multiple observational studies. While immunomodulating properties are well recognized, there are few longitudinal studies of 25(OH)D3 status, immune function and allergic disease in infants. OBJECTIVE: To investigate 25(OH)D3 levels at birth [cord blood (CB)] and at 6 months of age in relation to immune function at 6 months of age, and clinical outcomes up to 30 months of age in infants with a maternal history of atopy. METHODS: In a subset of infants (n = 225) enrolled in a RCT (ACTRN12606000281594), 25(OH)D3 levels were assessed in relation to peripheral blood mononuclear cell cytokine responses to house dust mite (HDM), ovalbumin (OVA) and ß-lactoglobulin allergens, or Toll-like receptor (TLR) ligands (lipopolysaccharide, lipoteichoic acid, polyinosinic : polycytidylic acid and CpG oligonucleotide) at 6 months of age, in addition to clinical outcomes (eczema, wheeze and allergen sensitisation) up to 30 months of age. RESULTS: Infants with higher 25(OH)D3 at birth (≥ 75 nmol/L, compared with < 50 nmol/L) had lower IL-5 and IL-13 responses to HDM by 6 months (P < 0.001 and P = 0.003, respectively). This was also reflected in strong inverse correlations between CB 25(OH)D3 levels and HDM IL-13 (ρ = -0.57; P = 0.0002) and IL-5 (ρ = -0.59, P = 0.0001) responses, with a similar trend for IL-5 (ρ = -0.29; P = 0.009) responses to OVA. For innate stimulations, higher 25(OH)D3 levels at 6 months were associated with greater responses to TLR ligands. Additionally, higher CB 25(OH)D3 was associated with reduced risk eczema at 6 months (P = 0.011) and 12 months (P = 0.034). CONCLUSION: This suggests that improving 25(OH)D3 status in pregnancy or early infancy may reduce the development of allergic disease in high-risk infants by inhibiting cytokine profiles associated with allergy. Results of clinical trials are awaited to determine the efficacy of vitamin D supplementation in allergy prevention.


Assuntos
Imunidade Adaptativa/fisiologia , Calcifediol/sangue , Imunidade Inata/fisiologia , Gravidez/sangue , Adulto , Alérgenos/imunologia , Alérgenos/farmacologia , Calcifediol/imunologia , Pré-Escolar , Citocinas/sangue , Citocinas/imunologia , Feminino , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Lactente , Masculino , Gravidez/imunologia , Fatores de Risco
19.
Br J Surg ; 102(2): e124-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25627125

RESUMO

BACKGROUND: The aim was to establish the feasibility of using a tissue stabilization gel (Allprotect™) as an alternative to liquid nitrogen to facilitate collection of clinical samples for translational research. METHODS: Tumour samples from patients undergoing surgery for primary or metastatic colorectal cancer were either snap-frozen in liquid nitrogen or stored in Allprotect™ under a number of different conditions. Sample integrity was compared across different storage conditions by assessing biomolecule stability and function. DNA quality was assessed spectrophotometrically and by KRas genotyping by pyrosequencing. Total RNA retrieval was determined by nanodrop indices/RNA integrity numbers, and quality assessed by reverse transcription-PCR for two representative genes (high-mobility group box 1, HMGB1; carboxylesterase 1, CES1) and two microRNAs (miR122 and let7d). Western blot analysis of HMGB1 and CES1 was used to confirm protein expression, and the metabolic conversion of irinotecan to its active metabolite, SN-38, was used to assess function. RESULTS: Under short-term storage conditions (up to 1 week) there was no apparent difference in quality between samples stored in Allprotect™ and those snap-frozen in liquid nitrogen. Some RNA degradation became apparent in tissue archived in Allprotect™ after 1 week, and protein degradation after 2 weeks. CONCLUSION: In hospitals that do not have access to liquid nitrogen and -80°C freezers, Allprotect™ provides a suitable alternative for the acquisition and stabilization of clinical samples. Storage proved satisfactory for up to 1 week, allowing transfer of samples without the need for specialized facilities. Surgical relevance Access to clinical material is a fundamental component of translational research that requires significant infrastructure (research personnel, liquid nitrogen, specialized storage facilities). The aim was to evaluate a new-to-market tissue stabilization gel (Allprotect™), which offers a simple solution to tissue preservation without the need for complex infrastructure. Allprotect™ offers comparable DNA, RNA and protein stabilization to tissue snap-frozen in liquid nitrogen for up to 1 week. Degradation of biomolecules beyond this highlights its role as a short-term tissue preservative. Allprotect™ has the potential to increase surgeon participation in translational research and surgical trials requiring tissue collection.


Assuntos
Géis/farmacologia , Preservação de Tecido/métodos , Pesquisa Translacional Biomédica/métodos , Análise de Variância , Neoplasias Colorretais/cirurgia , DNA/metabolismo , Estudos de Viabilidade , Humanos , RNA/metabolismo , Manejo de Espécimes/métodos
20.
Org Biomol Chem ; 13(3): 866-75, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25408103

RESUMO

Cps2L, a thymidylytransferase, is the first enzyme in Streptococcus pneumoniae L-rhamnose biosynthesis and an antibacterial target. We herein report the evaluation of six sugar phosphate analogues selected to further probe Cps2L substrate tolerance. A modified continuous spectrophotometric assay was employed for facile detection of pyrophosphate (PPi) released from nucleotidylyltransfase-catalysed condensation of sugar 1-phosphates and nucleoside triphosphates to produce sugar nucleotides. Additionally, experiments using waterLOGSY NMR spectroscopy were investigated as a complimentary method to evaluate binding affinity to Cps2L.


Assuntos
Antibacterianos/química , Proteínas de Bactérias/química , Inibidores Enzimáticos/química , Glucofosfatos/química , Nucleotidiltransferases/química , Antibacterianos/síntese química , Proteínas de Bactérias/antagonistas & inibidores , Difosfatos/análise , Ensaios Enzimáticos , Inibidores Enzimáticos/síntese química , Cinética , Nucleotidiltransferases/antagonistas & inibidores , Proteínas Recombinantes/química , Espectrofotometria , Streptococcus pneumoniae/química , Streptococcus pneumoniae/enzimologia
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