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1.
Ann Oncol ; 34(11): 1025-1034, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37619846

RESUMEN

BACKGROUND: The prognostic value of KRAS and BRAFV600E mutations in stage III colon cancer (CC) remains controversial and has never been clearly analyzed in patients with microsatellite instability-high (MSI-H) tumors due to sample size limitations. Data are also lacking for KRAS submutations and prognosis. PATIENTS AND METHODS: We examined clinicopathological variables and prognosis in patients with surgically resected stage III CC who participated in seven clinical trials from the ACCENT/IDEA databases. Associations between KRAS exon 2 and BRAFV600E mutations and time to recurrence (TTR), overall survival (OS), and survival after recurrence (SAR) were assessed using a Cox model. We also analyzed the prognostic value of KRAS exon 2 submutations. RESULTS: Among 8460 patients, 11.4% had MSI-H status. In the MSI-H group, BRAFV600E, KRAS exon 2 mutants, and double-wild-type statuses were detected in 40.6%, 18.1%, and 41.3%, respectively, whereas and in the microsatellite stable (MSS) group, these were detected in 7.7%, 38.6%, and 53.8%, respectively. In the MSS group, 5-year TTR rates of 61.8%, 66.3%, and 72.9% were observed among patients with BRAFV600E, KRAS exon 2 mutants, and those who were DWT, respectively [adjusted hazard ratio (HR) = 1.58 and 1.31, both P < 0.001]. In the MSI-H group, 5-year TTR rates did not differ significantly among the mutated subgroups. Similar results were found for OS. However, survival after relapse was significantly shorter in the KRAS exon 2- and BRAFV600E-mutated patients in both MSS (adjusted HR = 2.06 and 1.15; both P < 0.05) and MSI-H (adjusted HR = 1.99 and 1.81; both P < 0.05) groups. In the MSS group, KRAS exon 2 mutations were associated with TTR, but only p.G12C, p.G12D, and p.G13D were associated with poor outcomes after disease recurrence. CONCLUSIONS: Testing for both KRAS and BRAFV600E mutations in stage III patients should be considered as they can better define individual patient prognosis, and may also enable patient selection for (neo)adjuvant trials dedicated to specific molecular subtypes with poor prognosis.


Asunto(s)
Neoplasias del Colon , Inestabilidad de Microsatélites , Proteínas Proto-Oncogénicas B-raf , Proteínas Proto-Oncogénicas p21(ras) , Pronóstico , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Exones , Proteínas Proto-Oncogénicas B-raf/genética , Masculino , Femenino , Persona de Mediana Edad , Resultado del Tratamiento
2.
ESMO Open ; 7(6): 100594, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36327756

RESUMEN

BACKGROUND: Patients with microsatellite stable (MSS) colorectal carcinoma (CRC) do not respond to immune checkpoint inhibitors. Preclinical models suggested synergistic anti-tumour activity combining CXD101 and anti-programmed cell death protein 1 treatment; therefore, we assessed the clinical combination of CXD101 and nivolumab in heavily pre-treated patients with MSS metastatic CRC (mCRC). PATIENTS AND METHODS: This single-arm, open-label study enrolled patients aged 18 years or older with biopsy-confirmed MSS CRC; at least two lines of systemic anticancer therapies (including oxaliplatin and irinotecan); at least one measurable lesion; Eastern Cooperative Oncology Group performance status of 0, 1 or 2; predicted life expectancy above 3 months; and adequate organ and bone marrow function. Nine patients were enrolled in a safety run-in study to define a tolerable combination schedule of CXD101 and nivolumab, followed by 46 patients in the efficacy assessment phase. Patients in the efficacy assessment cohort were treated orally with 20 mg CXD101 twice daily for 5 consecutive days every 3 weeks, and intravenously with 240 mg nivolumab every 2 weeks. The primary endpoint was immune disease control rate (iDCR). RESULTS: Between 2018 and 2020, 55 patients were treated with CXD101 and nivolumab. The combination therapy was well tolerated with the most frequent grade 3 or 4 adverse events being neutropenia (18%) and anaemia (7%). Immune-related adverse reactions commonly ascribed to checkpoint inhibitors were surprisingly rare although we did see single cases of pneumonitis, hypothyroidism and hypopituitarism. There were no treatment-related deaths. Of 46 patients assessable for efficacy, 4 (9%) achieved partial response and 18 (39%) achieved stable disease, translating to an immune disease control rate of 48%. The median overall survival (OS) was 7.0 months (95% confidence interval 5.13-10.22 months). CONCLUSIONS: The primary endpoint was met in this phase II study, which showed that the combination of CXD101 and nivolumab, at full individual doses in the treatment of advanced or metastatic MSS CRC, was both well tolerated and efficacious.


Asunto(s)
Neoplasias Colorrectales , Nivolumab , Humanos , Nivolumab/farmacología , Nivolumab/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Repeticiones de Microsatélite
3.
Dis Aquat Organ ; 150: 1-16, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35796507

RESUMEN

The genera Paramoeba and Neoparamoeba (Amoebozoa, Dactylopodida, Paramoebidae) include well-known opportunistic pathogens associated with fish (N. peruans; amoebic gill disease), lobsters, molluscs and sea urchins, but only rarely with crabs (grey crab disease of blue crabs). Following reports of elevated post-capture mortality in edible crabs Cancer pagurus captured from a site within the English Channel fishery in the UK, a novel disease (amoebic crab disease, ACD) was detected in significant proportions of the catch. We present histopathological, transmission electron microscopy and molecular phylogenetic data, showing that this disease is defined by colonization of haemolymph, connective tissues and fixed phagocytes by amoeboid cells, leading to tissue destruction and presumably death in severely diseased hosts. The pathology was strongly associated with a novel amoeba with a phylogenetic position on 18S rRNA gene trees robustly sister to Janickina pigmentifera (which groups within the current circumscription of Paramoeba/Neoparamoeba), herein described as Janickina feisti n. sp. We provide evidence that J. feisti is associated with ACD in 50% of C. pagurus sampled from the mortality event. A diversity of other paramoebid sequence types, clustering with known radiations of N. pemaquidensis and N. aestuarina and a novel N. aestuarina sequence type, was detected by PCR in most of the crabs investigated, but their detection was much less strongly associated with clinical signs of disease. The discovery of ACD in edible crabs from the UK is discussed relative to published historical health surveys for this species.


Asunto(s)
Amebiasis , Amoeba , Braquiuros , Neoplasias , Amebiasis/veterinaria , Animales , Neoplasias/veterinaria , Filogenia , Reino Unido/epidemiología
4.
J Obstet Gynaecol ; 42(7): 2672-2679, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35727566

RESUMEN

Peripartum hypoxic neonatal brain injury cannot be accurately predicted with current foetal monitoring techniques. Neonatal brain monitoring through amplitude-integrated electroencephalography (aEEG) is utilised when brain injury is suspected. Intrapartum aEEG assessment may improve detection of foetal hypoxia, facilitating earlier intervention. Using different engineered configurations in adult volunteers (n = 18), we monitored aEEG through application of two foetal scalp electrodes (FSEs). This aided development of a novel signal splitter, our Foetal heart rate and aEEG Monitoring System (FEMS) to monitor aEEG intrapartum. We then compared FEMS with gold-standard EEG monitoring simultaneously in two adults. Average percentage of interpretable aEEG signal was 61.3%, with the FEMS obtaining 72.15%. EEG signal on the aEEG device consistently showed a similar trace to gold standard EEG. This study demonstrates feasibility of aEEG monitoring in adults with FEMS utilising FSE inputs. An intrapartum foetal study utilising FEMS is due to commence shortly. IMPACT STATEMENTWhat is already known on this subject? Cardiotography, the current gold standard in foetal monitoring, is not associated with a reduction in cerebral palsy or infant mortality rates. Neonatal amplitude-integrated electroencephalography (aEEG) is an established method of monitoring brain function to guide commencing cooling therapy in suspected hypoxic brain injury. Intrapartum animal studies have illustrated foetal EEG changes reflecting evolving hypoxia.What do the results of this study add? This study demonstrates aEEG monitoring in human adult volunteers through application of foetal scalp electrodes and use of a novel signal splitter. This Foetal heart rate and aEEG Monitoring System (FEMS) provided a good overall percentage of aEEG signal, consistently showing a similar trace to gold standard EEG.What the implications are of these findings for clinical practice and/or further research? This proof of principle study provides the first step in developing a novel intrapartum foetal monitoring technique to monitor foetal aEEG in labour. This provides an exciting prospect of transferring well established neonatal monitoring techniques to facilitate accurate brain function assessment intrapartum and early intervention to reduce hypoxic brain injury. An intrapartum foetal study of this technology is due to begin in the near future.


Asunto(s)
Lesiones Encefálicas , Encéfalo , Recién Nacido , Lactante , Animales , Femenino , Embarazo , Humanos , Adulto , Electroencefalografía/métodos , Lesiones Encefálicas/diagnóstico , Monitoreo Fetal , Voluntarios
5.
Front Genet ; 13: 869610, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35480328

RESUMEN

Limited access to technologies that support early monitoring of disease risk and a poor understanding of the geographically unique biological and environmental factors underlying disease, represent significant barriers to improved health outcomes and precision medicine efforts in low to middle income countries. These challenges are further compounded by the rich genetic diversity harboured within Southern Africa thus necessitating alternative strategies for the prediction of disease risk and clinical outcomes in regions where accessibility to personalized healthcare remains limited. The human microbiome refers to the community of microorganisms (bacteria, archaea, fungi and viruses) that co-inhabit the human body. Perturbation of the natural balance of the gut microbiome has been associated with a number of human pathologies, and the microbiome has recently emerged as a critical determinant of drug pharmacokinetics and immunomodulation. The human microbiome should therefore not be omitted from any comprehensive effort towards stratified healthcare and would provide an invaluable and orthogonal approach to existing precision medicine strategies. Recent studies have highlighted the overarching effect of geography on gut microbial diversity as it relates to human health. Health insights from international microbiome datasets are however not yet verified in context of the vast geographical diversity that exists throughout the African continent. In this commentary we discuss microbiome research in Africa and its role in future precision medicine initiatives across the African continent.

6.
J Invertebr Pathol ; 190: 107751, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35358597

RESUMEN

Wild Acetes sibogae australis from northern Moreton Bay, Australia displaying opacity of the hepatopancreas were sampled and examined histologically, revealing infection by multinucleate plasmodia of a haplosporidian-like parasite in the epithelial cells of the hepatopancreas. A morphological and phylogenetic investigation identified the parasite as a novel species of the order Haplosporida, and the parasite is described as Haplosporidium acetes n. sp. This is the first report of disease caused by a haplosporidian in wild Australian decapod crustaceans, and the first record of haplosporidiosis in sergestid shrimp. Infections of H. acetes were observed in all cell types (R, B, F and E) within the hepatopancreas. Infected epithelial cells became hypertrophied as they filled with haplosporidian parasites and, in heavy infections, caused almost complete displacement of normal hepatopancreas tissue. Although sporulation was not observed, infected jelly prawns appeared terminally diseased. Infections became grossly evident in around 5% of wild prawns during early autumn at a time of year when jelly prawn populations decline rapidly with decreasing water temperatures, however histopathology indicated at least 13% of apparently normal jelly prawns were also infected. Further studies are required in order to determine if this parasite influences jelly prawn population dynamics. In addition, we report co-infection of a novel microsporidian parasite in the Enterocytozoon Group Microsporidia (EGM) infecting nuclei of hepatopancreatic epithelial cells. The microsporidian was phylogenetically distinct from Enterocytozoon hepatopenaei (EHP) known to infect penaeid shrimp in Asia.


Asunto(s)
Haplosporidios , Microsporidios , Penaeidae , Animales , Australia , Hepatopáncreas , Penaeidae/parasitología , Filogenia
7.
Ann Oncol ; 31(4): 480-486, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32085892

RESUMEN

BACKGROUND: Since 2004, adjuvant 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX or FLOX) have been the standard of care for patients with resected colon cancer. Herein we examine the change of outcomes over a 10-year period in patients with stage III colon cancer who received this regimen. PATIENTS AND METHODS: Individual patient data from the ACCENT database was used to compare the outcomes in older (1998-2003) and newer (2004-2009) treatment eras for patients with stage III colon cancer who received adjuvant FOLFOX or FLOX. The outcomes were compared between the two groups by the multivariate Cox proportional-hazards model adjusting for age, sex, performance score, T stage, N stage, tumor sidedness, and histological grade. RESULTS: A total of 6501 patients with stage III colon cancer who received adjuvant FOLFOX or FLOX in six randomized trials were included in the analysis. Patients enrolled in the new era group experienced statistically significant improvement in time to recurrence [3-year rate, 76.1% versus 73.0%; adjusted hazard ratio (HRadj) = 0.83 (95% CI, 0.74-0.92), P = 0.0008], disease-free survival (DFS) [3-year rate, 74.7% versus 72.3%; HRadj = 0.88 (0.79-0.98), P = 0.024], survival after recurrence (SAR) [median time, 27.0 versus 17.7 months; HRadj = 0.65 (0.57-0.74), P < 0.0001], and overall survival (OS) [5-year rate, 80.9% versus 75.7%; HRadj = 0.78 (0.69-0.88), P < 0.0001]. The improved outcomes remained in patients diagnosed at 45 years of age or older, low-risk patients (T1-3 and N1), left colon, mismatch repair proficient (pMMR), BRAF, and KRAS wild-type tumors. CONCLUSION: Improved outcomes were observed in patients with stage III colon cancer enrolled in clinical trials who received adjuvant FOLFOX/FLOX therapy in 2004 or later compared with patients in the older era. Prolonged SAR calls for revalidation of 3-year DFS as the surrogate endpoint of OS in adjuvant clinical trials and reevaluation of optimal follow-up of OS to confirm the trial findings based on the DFS endpoints. CLINICAL TRIALS NUMBERS: NCT00079274; NCT00096278; NCT00004931; NCT00275210; NCT00265811; NCT00112918.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias del Colon , Recurrencia Local de Neoplasia , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Supervivencia sin Enfermedad , Fluorouracilo/uso terapéutico , Humanos , Leucovorina/uso terapéutico , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Oxaliplatino
8.
Ann Oncol ; 30(9): 1466-1471, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31268130

RESUMEN

BACKGROUND: Microsatellite instable/deficient mismatch repair (MSI/dMMR) metastatic colorectal cancers have been reported to have a poor prognosis. Frequent co-occurrence of MSI/dMMR and BRAFV600E complicates the association. PATIENTS AND METHODS: Patients with resected stage III colon cancer (CC) from seven adjuvant studies with available data for disease recurrence and MMR and BRAFV600E status were analyzed. The primary end point was survival after recurrence (SAR). Associations of markers with SAR were analyzed using Cox proportional hazards models adjusted for age, gender, performance status, T stage, N stage, primary tumor location, grade, KRAS status, and timing of recurrence. RESULTS: Among 2630 patients with cancer recurrence (1491 men [56.7%], mean age, 58.5 [19-85] years), multivariable analysis revealed that patients with MSI/dMMR tumors had significantly longer SAR than did patients with microsatellite stable/proficient MMR tumors (MSS/pMMR) (adjusted hazard ratio [aHR], 0.82; 95% CI [confidence interval], 0.69-0.98; P = 0.029). This finding remained when looking at patients treated with standard oxaliplatin-based adjuvant chemotherapy regimens only (aHR, 0.76; 95% CI, 0.58-1.00; P = 0.048). Same trends for SAR were observed when analyzing MSI/dMMR versus MSS/pMMR tumor subgroups lacking BRAFV600E (aHR, 0.84; P = 0.10) or those harboring BRAFV600E (aHR, 0.88; P = 0.43), without reaching statistical significance. Furthermore, SAR was significantly shorter in tumors with BRAFV600E versus those lacking this mutation (aHR, 2.06; 95% CI, 1.73-2.46; P < 0.0001), even in the subgroup of MSI/dMMR tumors (aHR, 2.65; 95% CI, 1.67-4.21; P < 0.0001). Other factors associated with a shorter SAR were as follows: older age, male gender, T4/N2, proximal primary tumor location, poorly differentiated adenocarcinoma, and early recurrence. CONCLUSIONS: In stage III CC patients recurring after adjuvant chemotherapy, and before the era of immunotherapy, the MSI/dMMR phenotype was associated with a better SAR compared with MSS/pMMR. BRAFV600E mutation was a poor prognostic factor for both MSI/dMMR and MSS/pMMR patients. TRIAL IDENTIFICATION NUMBERS: NCT00079274, NCT00265811, NCT00004931, NCT00004931, NCT00026273, NCT00096278, NCT00112918.


Asunto(s)
Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Inestabilidad de Microsatélites/efectos de los fármacos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Pronóstico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Reparación de la Incompatibilidad de ADN/efectos de los fármacos , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Mutación/genética , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Resultado del Tratamiento , Adulto Joven
9.
R Soc Open Sci ; 6(4): 181367, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31183115

RESUMEN

Chemical clock reactions are characterized by a relatively long induction period followed by a rapid 'switchover' during which the concentration of a clock chemical rises rapidly. In addition to their interest in chemistry education, these reactions are relevant to industrial and biochemical applications. A substrate-depletive, non-autocatalytic clock reaction involving household chemicals (vitamin C, iodine, hydrogen peroxide and starch) is modelled mathematically via a system of nonlinear ordinary differential equations. Following dimensional analysis, the model is analysed in the phase plane and via matched asymptotic expansions. Asymptotic approximations are found to agree closely with numerical solutions in the appropriate time regions. Asymptotic analysis also yields an approximate formula for the dependence of switchover time on initial concentrations and the rate of the slow reaction. This formula is tested via 'kitchen sink chemistry' experiments, and is found to enable a good fit to experimental series varying in initial concentrations of both iodine and vitamin C. The vitamin C clock reaction provides an accessible model system for mathematical chemistry.

10.
Anal Chim Acta ; 1053: 1-21, 2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30712554

RESUMEN

Microencapsulation of living cells is a field that has been heavily investigated by many researchers over the past two decades. Numerous experimental setups have been developed to encapsulate living cells in microbeads using different microfluidic devices and materials. Previous studies have investigated different microfluidic devices and materials for use in cancer treatment, drug delivery, environmental remediation, food production, and cell culture contexts. Some of the current challenges to these setups are maintaining reasonable levels of cell viability, cell leaching, nutrient and oxygen diffusion, and ensuring uniform microbead shape and size distribution. Addressing these issues and identifying the most reproducible and convenient setup enables researchers to efficiently encapsulate living cells and further advance the biomedical field. The efficiency of microencapsulation in terms of cell viability and uniform microbead shape and size distribution are directly related to the type of device used and the cross-linking method applied. Hence, the focus of this review is to assess the effects of using T-junction, flow-focusing, and co-flow microfluidic devices as well as thermal, ionic, and photo cross-linking methods for the microencapsulation of living cells. Recent applications of bacteria microencapsulation using microfluidic systems since 2017 are presented.


Asunto(s)
Dispositivos Laboratorio en un Chip , Microtecnología/métodos , Animales , Cápsulas , Supervivencia Celular , Humanos , Microtecnología/instrumentación
11.
Ned Tijdschr Tandheelkd ; 125(11): 593-601, 2018 11.
Artículo en Holandés | MEDLINE | ID: mdl-30457580

RESUMEN

Evidence-based reviews of drugs causing medication-induced salivary gland dysfunction, such as xerostomia (sensation of oral dryness) and subjective sialorrhea are lacking. To compile a list of medicaments that influence salivary gland function, electronic databases were searched for relevant articles published up to June 2013. A total of 269 papers out of 3,867 records located satisfied the inclusion criteria (relevance, quality of methodology, strength of evidence). A total of 56 active substances with a higher level of evidence and 50 active substances with a moderate level of evidence of causing salivary gland dysfunction are described in this article. While xerostomia was a commonly reported outcome, the objective effect on salivary secretion was rarely measured. Xerostomia was, moreover, mostly reported as a negative side effect instead of the intended effect of that drug. A comprehensive list of medications having documented effects on salivary gland function or symptoms was compiled, which may assist practitioners in assessing patients who complain of dry mouth while taking medications.


Asunto(s)
Glándulas Salivales/efectos de los fármacos , Xerostomía/etiología , Humanos
12.
Heliyon ; 4(6): e00657, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29942873

RESUMEN

Cellulolytic bacteria that produce cellulases, which are active over a range of pH and temperatures, can be used to catalyze hydrolysis of pretreated lignocellulosic material. This is important in the production of second generation biofuels among other biotechnological applications. In this investigation, bacteria isolated from sugarcane bagasse were identified as strains of Enterobacter xiangfangensis, Serratia rubidaea, Klebsiella pneumoniae and a novel species of Citrobacter designated Citrobacter sp. UWIBGS10. The glucose production potential of these strains was studied on thermally and solvent pretreated sugarcane bagasse. This was performed at 24-hour intervals up to 168 hours in the range of pH 5-9 and temperature range 25-40 °C. Maximal concentrations of glucose for Citrobacter sp. UWIBGS10 occurred at pH 6 and 25 °C. For E. xiangfangensis, S. rubidaea, K. pneumoniae glucose concentrations were consistent across the pH and temperature ranges examined. From these results it could be concluded that the bacteria demonstrated ability for lignocellulolytic hydrolysis for the production of glucose and could be further explored for the characterization of commercial cellulolytic enzymes.

13.
Parasitology ; 145(11): 1483-1492, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29886855

RESUMEN

Marteilia refringens causes marteiliosis in oysters, mussels and other bivalve molluscs. This parasite previously comprised two species, M. refringens and Marteilia maurini, which were synonymized in 2007 and subsequently referred to as M. refringens 'O-type' and 'M-type'. O-type has caused mass mortalities of the flat oyster Ostrea edulis. We used high throughput sequencing and histology to intensively screen flat oysters and mussels (Mytilus edulis) from the UK, Sweden and Norway for infection by both types and to generate multi-gene datasets to clarify their genetic distinctiveness. Mussels from the UK, Norway and Sweden were more frequently polymerase chain reaction (PCR)-positive for M-type (75/849) than oysters (11/542). We did not detect O-type in any northern European samples, and no histology-confirmed Marteilia-infected oysters were found in the UK, Norway and Sweden, even where co-habiting mussels were infected by the M-type. The two genetic lineages within 'M. refringens' are robustly distinguishable at species level. We therefore formally define them as separate species: M. refringens (previously O-type) and Marteilia pararefringens sp. nov. (M-type). We designed and tested new Marteilia-specific PCR primers amplifying from the 3' end of the 18S rRNA gene through to the 5.8S gene, which specifically amplified the target region from both tissue and environmental samples.


Asunto(s)
Cercozoos/clasificación , Mytilus edulis/parasitología , Ostrea/parasitología , Infecciones Protozoarias en Animales/epidemiología , Animales , Secuenciación de Nucleótidos de Alto Rendimiento , Noruega , Reacción en Cadena de la Polimerasa , ARN Ribosómico 18S/genética , Suecia , Reino Unido
14.
Ann Oncol ; 29(3): 616-623, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29293881

RESUMEN

Background: We report here the prognostic value of ploidy and digital tumour-stromal morphometric analyses using material from 2624 patients with early stage colorectal cancer (CRC). Patients and methods: DNA content (ploidy) and stroma-tumour fraction were estimated using automated digital imaging systems and DNA was extracted from sections of formalin-fixed paraffin-embedded (FFPE) tissue for analysis of microsatellite instability. Samples were available from 1092 patients recruited to the QUASAR 2 trial and two large observational series (Gloucester, n = 954; Oslo University Hospital, n = 578). Resultant biomarkers were analysed for prognostic impact using 5-year cancer-specific survival (CSS) as the clinical end point. Results: Ploidy and stroma-tumour fraction were significantly prognostic in a multivariate model adjusted for age, adjuvant treatment, and pathological T-stage in stage II patients, and the combination of ploidy and stroma-tumour fraction was found to stratify these patients into three clinically useful groups; 5-year CSS 90% versus 83% versus 73% [hazard ratio (HR) = 1.77 (95% confidence interval (95% CI): 1.13-2.77) and HR = 2.95 (95% CI: 1.73-5.03), P < 0.001]. Conclusion: A novel biomarker, combining estimates of ploidy and stroma-tumour fraction, sampled from FFPE tissue, identifies stage II CRC patients with low, intermediate or high risk of CRC disease specific death, and can reliably stratify clinically relevant patient sub-populations with differential risks of tumour recurrence and may support choice of adjuvant therapy for these individuals.


Asunto(s)
Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/clasificación , Supervivencia sin Enfermedad , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Ploidias , Pronóstico , Estudios Retrospectivos , Microambiente Tumoral
15.
Heredity (Edinb) ; 119(3): 125-135, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28561806

RESUMEN

An individual's genes may influence the phenotype of neighboring conspecifics. Such indirect genetic effects (IGEs) are important as they can affect the apparent total heritable variance in a population, and thus the response to selection. We studied these effects in a large, pedigreed population of Eucalyptus globulus using variance component analyses of Mycosphearella leaf disease, diameter growth at age 2 years, and post-infection diameter growth at ages 4 and 8 years. In a novel approach, we initially modeled IGEs using a factor analytic (FA) structure to identify the most influential neighbor positions, with the FA loadings being position-specific regressions on the IGEs. This involved sequentially comparing FA models for the variance-covariance matrices of the direct and indirect effects of each neighbor. We then modeled IGEs as a distance-based, combined effect of the most influential neighbors. This often increased the magnitude and significance of indirect genetic variance estimates relative to using all neighbors. The extension of a univariate IGEs model to bivariate analyses also provided insights into the genetic architecture of this population, revealing that: (1) IGEs arising from increased probability of neighbor infection were not associated with reduced growth of neighbors, despite adverse fitness effects being evident at the direct genetic level; and (2) the strong, genetic-based competitive interactions for growth, established early in stand development, were highly positively correlated over time. Our results highlight the complexities of genetic-based interactions at the multi-trait level due to (co)variances associated with IGEs, and the marked discrepancy occurring between direct and total heritable variances.


Asunto(s)
Eucalyptus/crecimiento & desarrollo , Eucalyptus/genética , Enfermedades de las Plantas/genética , Cruzamientos Genéticos , Ambiente , Modelos Genéticos , Modelos Estadísticos , Fenotipo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Selección Genética
16.
Parasitology ; 144(2): 186-199, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27748227

RESUMEN

The Paramyxida, closely related to haplosporidians, paradinids, and mikrocytids, is an obscure order of parasitic protists within the class Ascetosporea. All characterized ascetosporeans are parasites of invertebrate hosts, including molluscs, crustaceans and polychaetes. Representatives of the genus Marteilia are the best studied paramyxids, largely due to their impact on cultured oyster stocks, and their listing in international legislative frameworks. Although several examples of microsporidian hyperparasitism of paramyxids have been reported, phylogenetic data for these taxa are lacking. Recently, a microsporidian parasite was described infecting the paramyxid Marteilia cochillia, a serious pathogen of European cockles. In the current study, we investigated the phylogeny of the microsporidian hyperparasite infecting M. cochillia in cockles and, a further hyperparasite, Unikaryon legeri infecting the digenean Meiogymnophallus minutus, also in cockles. We show that rather than representing basally branching taxa in the increasingly replete Cryptomycota/Rozellomycota outgroup (containing taxa such as Mitosporidium and Paramicrosoridium), these hyperparasites instead group with other known microsporidian parasites infecting aquatic crustaceans. In doing so, we erect a new genus and species (Hyperspora aquatica n. gn., n.sp.) to contain the hyperparasite of M. cochillia and clarify the phylogenetic position of U. legeri. We propose that in both cases, hyperparasitism may provide a strategy for the vectoring of microsporidians between hosts of different trophic status (e.g. molluscs to crustaceans) within aquatic systems. In particular, we propose that the paramyxid hyperparasite H. aquatica may eventually be detected as a parasite of marine crustaceans. The potential route of transmission of the microsporidian between the paramyxid (in its host cockle) to crustaceans, and, the 'hitch-hiking' strategy employed by H. aquatica is discussed.


Asunto(s)
Cercozoos/parasitología , Microsporidios/genética , Microsporidios/fisiología , Animales , Cercozoos/ultraestructura , Crustáceos/parasitología , Interacciones Huésped-Parásitos , Microsporidios/ultraestructura , Filogenia , ARN Protozoario/genética
18.
Occup Med (Lond) ; 66(9): 719-724, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27932489

RESUMEN

BACKGROUND: Work Positive is Ireland's national policy initiative to control work-related stress. Since the introduction of the UK Health and Safety Executive's Management Standards (MS) in 2004, a number of studies have been undertaken to assess the potential adaptation of the MS framework within Ireland. AIMS: To investigate the dimensionality, reliability and validity of the Irish version of the MS Indicator Tool (ROI-MSIT). METHODS: Between February 2011 and June 2014, we collected data from a wide range of public and private sector organizations that used the ROI-MSIT. In addition to the ROI-MSIT, respondents completed the WHO-Five Well-being Index (WHO-5). Exploratory factor analysis (EFA) was used to determine whether the ROI-MSIT maintained the structure of the UK instrument. The internal consistency of the ROI-MSIT was also assessed to determine its reliability, while its criterion-related validity was explored through correlation analysis with the WHO-5. RESULTS: Data were collected from 7377 participants. The factor structure of the ROI-MSIT consisted of six factors; the Demands, Control, Peer Support, Relationships and Role factors were equivalent to the original UK factors. Like the Italian version, a principal factor emerged that combined the Manager Support and Change domains. Cronbach's alpha scores ranged from 0.75 to 0.91. Finally, the ROI-MSIT's subscales and WHO-5 were positively correlated (r = 0.42-0.59, P < 0.001). CONCLUSIONS: The ROI-MSIT is reliable and valid, with a factor structure similar to the original UK instrument and the Italian MSIT. Further psychometric evaluation of the ROI-MSIT is recommended.


Asunto(s)
Auditoría Administrativa/métodos , Percepción , Psicometría/normas , Adulto , Análisis Factorial , Femenino , Humanos , Irlanda , Liderazgo , Masculino , Auditoría Administrativa/estadística & datos numéricos , Persona de Mediana Edad , Psicometría/métodos , Reproducibilidad de los Resultados , Estrés Psicológico/diagnóstico , Estrés Psicológico/etiología , Encuestas y Cuestionarios , Lugar de Trabajo/normas , Lugar de Trabajo/estadística & datos numéricos
19.
Br Dent J ; 221(4): 149, 2016 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-27561559
20.
Parasitology ; 143(8): 971-82, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27001103

RESUMEN

Almost half of all known microsporidian taxa infect aquatic animals. Of these, many cause disease in arthropods. Hepatospora, a recently erected genus, infects epithelial cells of the hepatopancreas of wild and farmed decapod crustaceans. We isolated Hepatospora spp. from three different crustacean hosts, inhabiting different habitats and niches; marine edible crab (Cancer pagurus), estuarine and freshwater Chinese mitten crab (Eriocheir sinensis) and the marine mussel symbiont pea crab (Pinnotheres pisum). Isolates were initially compared using histology and electron microscopy revealing variation in size, polar filament arrangement and nuclear development. However, sequence analysis of the partial SSU rDNA gene could not distinguish between the isolates (~99% similarity). In an attempt to resolve the relationship between Hepatospora isolated from E. sinensis and C. pagurus, six additional gene sequences were mined from on-going unpublished genome projects (RNA polymerase, arginyl tRNA synthetase, prolyl tRNA synthetase, chitin synthase, beta tubulin and heat shock protein 70). Primers were designed based on the above gene sequences to analyse Hepatospora isolated from pea crab. Despite application of gene sequences to concatenated phylogenies, we were unable to discriminate Hepatospora isolates obtained from these hosts and concluded that they likely represent a single species or, at least subspecies thereof. In this instance, concatenated phylogenetic analysis supported the SSU-based phylogeny, and further, demonstrated that microsporidian taxonomies based upon morphology alone are unreliable, even at the level of the species. Our data, together with description of H. eriocheir in Asian crab farms, reveal a preponderance for microvariants of this parasite to infect the gut of a wide array of decapods crustacean hosts and the potential for Hepatospora to exist as a cline across wide geographies and habitats.


Asunto(s)
Braquiuros/microbiología , Microsporidios/clasificación , Microsporidiosis/veterinaria , Animales , Cartilla de ADN/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Hepatopáncreas/microbiología , Hepatopáncreas/patología , Microsporidios/genética , Microsporidios/aislamiento & purificación , Microsporidios/ultraestructura , Microsporidiosis/microbiología , Filogenia , Análisis de Secuencia de ADN/veterinaria
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