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White spot syndrome virus (WSSV), which causes white spot disease, is one of the notoriously feared infectious agents in the shrimp industry, inflicting estimated production losses world-wide of up to US$1 billion annually. Cost-effective accessible surveillance testing and targeted diagnosis are key to alerting shrimp industries and authorities worldwide early about WSSV carrier status in targeted shrimp populations. Here we present key validation pathway metrics for the Shrimp MultiPathTM (SMP) WSSV assay as part of the multi-pathogen detection platform. With superior throughput, fast turn-around time, and extremely low cost per test, the SMP WSSV assay achieves a high level of analytical sensitivity (~2.9 copies), perfect analytical specificity (~100%), and good intra- and inter-run repeatability (coefficient of variation <5%). The diagnostic metrics were estimated using Bayesian latent class analysis on data from 3 experimental shrimp populations from Latin America with distinct WSSV prevalence and yielded a diagnostic sensitivity of 95% and diagnostic specificity of 99% for SMP WSSV, which was higher than these parameters for the TaqMan quantitative PCR (qPCR) assays currently recommended by the World Organisation for Animal Health and the Commonwealth Scientific and Industrial Research Organisation. This paper additionally presents compelling data for the use of synthetic double-stranded DNA analyte spiked into pathogen-naïve shrimp tissue homogenate as a means to substitute clinical samples for assay validation pathways targeting rare pathogens. SMP WSSV shows analytical and diagnostic metrics comparable to qPCR-based assays and demonstrates fit-for-purpose performance for detection of WSSV in clinically diseased and apparently healthy animals.
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Penaeidae , Virus del Síndrome de la Mancha Blanca 1 , Animales , Virus del Síndrome de la Mancha Blanca 1/genética , Teorema de Bayes , Reacción en Cadena de la Polimerasa/veterinariaRESUMEN
Enterocytozoon hepatopenaei (EHP) infections are a global challenge for the Penaeid shrimp industry with a sharp rise in prevalence over the last 10 yr. EHP is known to cause sub-optimal growth, large size variation and reduced survival of shrimp. Molecular methods development has mainly focussed on 18S rRNA or spore wall protein 1 (SWP1). Due to the specificity and sensitivity issues with previously designed assays for both targets, new molecular assays are needed by the global shrimp industry and regulators to help manage the risks posed by EHP. This paper describes new real-time PCR (qPCR) methods developed for the novel EHP gene targets polar tube protein 2 (PTP2) and spore wall protein 26 (SWP26), whilst also presenting performance metrics of the new Shrimp MultiPathTM technology EHP assay. qPCR assays PTP2G and SWP26G show high amplification efficiency, a limit of detection (LOD) of between 1 and 4 copies, low assay variation and high diagnostic sensitivity (DSe) and specificity (DSp) compared to imperfect reference assays. Similar performance is seen with Shrimp MultiPathTM EHP showing an LOD of 8 copies, low assay variation and high DSe and DSp. These novel molecular targets for EHP and Shrimp MultiPathTM EHP strengthen global efforts to monitor and mitigate risks of EHP infections and outbreaks. Moreover, this study presents novel data on distribution of EHP in shrimp populations from South-East Asia and Latin America, and how sequence variations need to be considered when monitoring EHP in different geographies.
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Enterocytozoon , Penaeidae , Animales , Enterocytozoon/genética , América Latina , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinariaRESUMEN
We present a hierarchical Bayesian framework for the selection of force fields in molecular dynamics (MD) simulations. The framework associates the variability of the optimal parameters of the MD potentials under different environmental conditions with the corresponding variability in experimental data. The high computational cost associated with the hierarchical Bayesian framework is reduced by orders of magnitude through a parallelized Transitional Markov Chain Monte Carlo method combined with the Laplace Asymptotic Approximation. The suitability of the hierarchical approach is demonstrated by performing MD simulations with prescribed parameters to obtain data for transport coefficients under different conditions, which are then used to infer and evaluate the parameters of the MD model. We demonstrate the selection of MD models based on experimental data and verify that the hierarchical model can accurately quantify the uncertainty across experiments; improve the posterior probability density function estimation of the parameters, thus, improve predictions on future experiments; identify the most plausible force field to describe the underlying structure of a given dataset. The framework and associated software are applicable to a wide range of nanoscale simulations associated with experimental data with a hierarchical structure.
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We recently found variants in cancer stem cell genes (CD44, ALCAM and LGR5) significantly associated with increased time to recurrence (TTR) in patients with stage III and high-risk stage II colon cancer treated with 5-fluorouracil (5-FU)-based chemotherapy. In this study, we validated these genetic biomarkers in a large and independent patient cohort (n=599). Patients who received 5-FU-based adjuvant chemotherapy (n=391) carrying at least one C allele in LGR5 rs17109924 had a significantly increased TTR compared with patients carrying the homozygous T/T variant (HR 0.38, 95%CI 0.19-0.79; P=0.006). In patients treated with surgery alone (n=208), no association between LGR rs17109924 and TTR was found (P=0.728). In the multivariate Cox-analysis, LGR5 rs17109924 remained statistically significant (HR 0.38, 95%CI 0.18-0.78; P=0.008) for patients who received adjuvant chemotherapy. We confirmed in a large and independent study cohort that LGR5 rs17109924 is a predictive genetic biomarker for TTR in patients with colon cancer treated with 5-FU-based adjuvant chemotherapy.
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Biomarcadores de Tumor/genética , Neoplasias del Colon/tratamiento farmacológico , Fluorouracilo/administración & dosificación , Receptores Acoplados a Proteínas G/genética , Adulto , Quimioterapia Adyuvante , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Polimorfismo de Nucleótido Simple , PronósticoRESUMEN
BACKGROUND: Inflammation has a critical role in the pathogenesis and progression of cancer. The lymphocyte to monocyte ratio (LMR) could be shown to be prognostic in haematologic neoplasia. In this study, we analysed the LMR with clinical outcome in stage II and III colon cancer patients. METHODS: Three hundred and seventy-two patients with stage II and III colon cancer were included in this retrospective study. Kaplan-Meier curves and multivariate Cox-regression analyses were calculated for time to recurrence (TTR) and overall survival (OS). RESULTS: Including all patients, the elevated preoperative LMR was significantly associated with increased TTR and OS in multivariate analysis (HR: 0.47, 95%CI: 0.29-0.76, P=0.002; HR: 0.51, 95%CI: 0.31-0.83, P=0.007; respectively). In subanalyses, the association was limited to patients with stage III (HR: 0.40, 95%CI: 0.22-0.72, P=0.002), in contrast to patients with stage II (HR: 0.40, 95%CI: 0.28-1.66, P=0.397). When the subgroup of patients with 'high-risk' LMR≤2.83 was analysed, no benefit of adjuvant 5-FU-based chemotherapy could be found (HR: 0.99; 95%CI: 0.60-1.63; P=0.953). CONCLUSION: The LMR might be an independent prognostic marker for TTR in stage III colon cancer patients. Our results further suggest that high-risk patients based on the LMR do not benefit from adjuvant chemotherapy. Independent validation of our findings is warranted.
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Neoplasias del Colon/sangre , Neoplasias del Colon/patología , Linfocitos/patología , Monocitos/patología , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante/métodos , Neoplasias del Colon/tratamiento farmacológico , Femenino , Fluorouracilo/uso terapéutico , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Periodo Preoperatorio , Pronóstico , Modelos de Riesgos Proporcionales , Estudios RetrospectivosRESUMEN
BACKGROUND: Recent evidence indicates that the host inflammatory response has an important role in the tumour progression. Elevated C-reactive protein (CRP) levels have been previously associated with poor prognosis in several cancer types including small-scale studies in pancreatic cancer (PC) patients. The purpose of the present study was to validate the prognostic impact of plasma CRP levels at date of diagnosis on cancer-specific survival (CSS) in a large cohort of PC patients. METHODS: Data from 474 consecutive patients with adenocarcinoma of the pancreas, treated between 2004 and 2012 at a single centre, were evaluated retrospectively. CSS was analysed using the Kaplan-Meier method. To evaluate the prognostic significance of plasma CRP levels, univariate and multivariate Cox analyses were applied. RESULTS: High plasma CRP levels at diagnosis were significantly associated with well-established prognostic factors, including high tumour stage and tumour grade and the administration of chemotherapy (P<0.05). In univariate analysis, we observed that a high plasma CRP level was a consistent factor for poor CSS in PC patients (hazard ratio (HR)=2.21; 95% confidence interval (CI)=1.68-2.92, P<0.001). In multivariate analysis, tumour stage, grade, administration of chemotherapy, a high neutrophil-lymphocyte ratio and the highest quartile of CRP levels (HR=1.60, 95% CI=1.16-2.21; P=0.005) were identified as independent prognostic factors in PC patients. CONCLUSION: In conclusion, we confirmed a significant association of elevated CRP levels with poor clinical outcome in PC patients. Our results indicate that the plasma CRP level might represent a useful marker for patient stratification in PC management.
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Proteína C-Reactiva/metabolismo , Carcinoma Ductal Pancreático/sangre , Neoplasias Pancreáticas/sangre , Anciano , Carcinoma Ductal Pancreático/patología , Estudios de Cohortes , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Pronóstico , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
OBJECTIVE: To examine the role of the social gradient on multiple health outcomes and behaviors. It was predicted that higher levels of SES, measured by educational attainment and family income, would be associated with positive health behaviors (i.e., smoking, drinking, physical activity, and diet) and health status (i.e., limited physical activity due to chronic condition, blood pressure, obesity, diabetes, BMI, and perceived health condition). The study also examined the differential effects of the social gradient in health among different racial/ethnic groups (i.e., non-Hispanic Whites, Blacks, Asian, Hispanics, and American Indians). STUDY DESIGN: Cross-sectional study. METHODS: The data were from the adult 2009 California Health Interview Survey (CHIS). Weighted multivariable linear and logistic regression models were conducted to examine trends found between SES and health conditions and health behaviors. Polynomial trends were examined for all linear and logistic models to test for the possible effects (linear, quadratic, and cubic) of the social gradient on health behaviors and outcomes stratified by race/ethnicity. RESULTS: Findings indicated that, in general, Whites had more favorable health profiles in comparison to other racial/ethnic groups with the exception of Asians who were likely to be as healthy as or healthier than Whites. Predicted marginals indicated that Asians in the upper two strata of social class display the healthiest outcomes of health status among all other racial/ethnic groups. Also, the social gradient was differentially associated with health outcomes across race/ethnicity groups. While the social gradient was most consistently observed for Whites, education did not have the same protective effect on health among Blacks and American Indians. Also, compared to other minority groups, Hispanics and Asians were more likely to display curvilinear trends of the social gradient: an initial increase from low SES to mid-level SES was associated with worse health outcomes and behaviors; however, continued increase from mid-SES to high SES saw returns to healthy outcomes and behaviors. CONCLUSION: The study contributes to the literature by illustrating unique patterns and trends of the social gradient across various racial/ethnic populations in a nationally representative sample. Future studies should further explore temporal trends to track the impact of the social gradient for different racial and ethnic populations in tandem with indices of national income inequalities.
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Etnicidad/estadística & datos numéricos , Disparidades en el Estado de Salud , Grupos Raciales/estadística & datos numéricos , Adulto , California , Estudios Transversales , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Factores Socioeconómicos , Estados UnidosRESUMEN
BACKGROUND: Inflammation has a critical role in the pathogenesis and progression of cancer. Recently, the derived neutrophil to lymphocyte ratio (absolute count of neutrophils divided by the absolute white cell count minus the absolute count of neutrophils; dNLR) has been shown to influence clinical outcome in various cancer entities. In this study, we analysed the dNLR with clinical outcome in stage II and III colon cancer patients. METHODS: Three-hundred and seventy-two patients with stage II and III colon cancer were included in this retrospective study. Kaplan-Meier curves and multivariate Cox proportion analyses were calculated for time to recurrence (TTR) and overall survival (OS). RESULTS: In univariate analysis, the elevated preoperative dNLR was significantly associated with decreased TTR (hazard ratio (HR) 2.38, 95% confidence interval (CI) 1.57-3.6, P<0.001) and remained significant in multivariate analysis. Patients with dNLR >3 had a median TTR of 83 months, and patients with dNLR ≤ 3 showed a median TTR of 132 months. In OS analysis, a dNLR >2.2 was significantly associated with decreased OS in univariate (HR 1.85, 95% CI 1.11-3.08, P=0.018) and multivariate analysis. Patients with dNLR >2.2 showed a median OS of 121 months, and patients with dNLR ≤ 2.2 had a median OS of 147 months. CONCLUSION: The dNLR may be an independent prognostic marker for TTR and OS in patients with stage II and III colon cancer. Independent validation of our findings is warranted.
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Neoplasias del Colon/patología , Linfocitos/patología , Neutrófilos/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/mortalidad , Femenino , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
Rotaviruses (RV) have a high prevalence in piggeries worldwide and are one of the major pathogens causing severe diarrhoea in young pigs. RV species A, B, and C have been linked to piglet diarrhoea in Australian pig herds, but their genetic diversity has not been studied in detail. Based on sequencing of the structural viral protein 7 (VP7) RVA G genotypes G3, G4 and G5, and RVC types G1, G3, G5, and G6 have been identified in Australian piggeries in previous studies. Although occurrence of RVB was reported in Australia in 1988, no further genetic analysis has been conducted. To improve health management decisions in Australian pig herds, more information on RV prevalence and genetic diversity is needed. Here, 243 enteric samples collected from 20 pig farms within Eastern Australia were analysed for the presence of RV in different age groups using a novel PCR-based multiplex assay (Pork MultiPath™ enteric panel). RVA, RVB, and RVC were detected in 10, 14, and 14 farms, respectively. Further sequencing of VP7 in selected RV-positive samples revealed G genotypes G2, G5, G9 (RVA), G6, G8, G14, G16, G20 (RVB), and G1, G3, G5, G6 (RVC) present. RVA was only detected in young (<10 weeks old) pigs whereas RVB and RVC were also detected in older animals (>11 weeks old). Interestingly, RVB and RVC G-type occurrence differed between age groups. In conclusion, this study provides new insights on the prevalence and diversity of different RV species in pig herds of Eastern Australia whilst demonstrating the ability of the Pork MultiPath™ technology to accurately differentiate between these RV species.
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Infecciones por Rotavirus , Rotavirus , Enfermedades de los Porcinos , Animales , Porcinos , Rotavirus/genética , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/veterinaria , Enfermedades de los Porcinos/epidemiología , Australia/epidemiología , Diarrea/veterinaria , Genotipo , Variación Genética , FilogeniaRESUMEN
BACKGROUND: In 1999, 270,000 cases of cancer were registered in the United Kingdom, placing a large burden on the NHS. Cancer outcome data in 1999 suggested that UK survival rates were poorer than most other European countries. In the same year, a Department of Health review noted that clinical trials accrual was poor (<3.5% of incident cases) and hypothesised that increasing research activity might improve outcomes and reduce the variability of outcomes across England. Thus, the National Cancer Research Network (NCRN) was established to increase participation in cancer clinical research. METHODS: The NCRN was established in 2001 to provide a robust infrastructure for cancer clinical research and improvements in patient care. Remit of NCRN is to coordinate, support and deliver cancer clinical research through the provision of research support staff across England. The NCRN works closely with similar networks in Scotland, Wales and the Northern Ireland. A key aim of NCRN is to improve the speed of research and this was also assessed by comparing the speed of study delivery of a subset of cancer studies opening before and after NCRN was established. RESULTS: Patient recruitment increased through NCRN, with almost 32,000 (12% of annual incident cases) cancer patients being recruited each year. Study delivery has improved, with more studies meeting the recruitment target - 74% compared with 39% before NCRN was established. CONCLUSION: The coordinated approach to cancer clinical research has demonstrated increased accrual, wide participation and successful trial delivery, which should lead to improved outcomes and care.
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Ensayos Clínicos como Asunto/métodos , Neoplasias/terapia , Ensayos Clínicos como Asunto/normas , Humanos , Neoplasias/epidemiología , Selección de Paciente , Reino Unido/epidemiologíaRESUMEN
In the late 1990 s, in response to poor national cancer survival figures, government monies were invested to enhance recruitment to clinical cancer research. Commencing with England in 2001 and then rolling out across all four countries, a network of clinical cancer research infrastructure was created, the new staff being linked to existing clinical care structures including multi-disciplinary teams. In parallel, a UK-wide co-ordination of cancer research funders driven by the 'virtual' National Cancer Research Institute, combined to create a 'whole-system approach' linking research funders, researchers and NHS clinicians all working to the same ends. Over the next 10 years, recruitment to clinical trials and other well-designed studies, increased 4-fold, reaching 17% of the incident cancer population, the highest national rate world-wide. The additional resources led to more studies opened, and more patients recruited across the country, for all types of cancers and irrespective of additional clinical research staff in some hospitals. In 2006, a co-ordinated decision was made to increasingly focus on randomized trials, leading to increased recruitment, without any fall-off in accrual to non-randomized and observational studies. The National Cancer Research Network has supported large successful trials which are changing clinical practice in many cancers.
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Investigación Biomédica/métodos , Oncología Médica/métodos , Neoplasias/terapia , Investigación Biomédica/normas , Humanos , Oncología Médica/normas , Ensayos Clínicos Controlados Aleatorios como Asunto , Medicina Estatal , Resultado del Tratamiento , Reino UnidoAsunto(s)
Traumatismos del Nacimiento/diagnóstico , Traumatismos del Nacimiento/etiología , Fracturas Abiertas/diagnóstico , Fracturas Abiertas/etiología , Síndrome del Pelo Ensortijado/diagnóstico , Hueso Occipital/lesiones , Hueso Parietal/lesiones , Fracturas Craneales/diagnóstico , Fracturas Craneales/etiología , Cesárea , Discapacidades del Desarrollo/diagnóstico , Discapacidades del Desarrollo/etiología , Electroencefalografía , Estudios de Seguimiento , Humanos , Imagenología Tridimensional , Lactante , Recién Nacido , Masculino , Examen Neurológico , Hueso Occipital/diagnóstico por imagen , Hueso Parietal/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: The herbal Petasites hybridus (butterbur) extract (Ze 339, PET) is known to have leukotriene inhibiting properties, and therefore might inhibit allergic diseases. METHODS: The effect of PET was investigated in ovalbumin (OVA) immunized BALB/c mice given intranasally together with antigen challenge in the murine model of allergic airway disease (asthma) with the analysis of the inflammatory and immune parameters in the lung. RESULTS: PET given with the antigen challenge inhibited the allergic response. PET inhibited airway hyperresponsiveness (AHR) and eosinophil recruitment into the bronchoalveolar lavage (BAL) fluid upon allergen challenge, but had no effect in the saline control mice. Eosinophil recruitment was further assessed in the lung by eosinophil peroxidase (EPO) activity at a concentration of 100 microg PET. Microscopic investigations revealed less inflammation, eosinophil recruitment and mucus hyperproduction in the lung with 100 microg PET. Diminution of AHR and inflammation was associated with reduced IL-4, IL-5 and RANTES production in the BAL fluid with 30 microg PET, while OVA specific IgE and eotaxin serum levels remained unchanged. CONCLUSION: PET, which has been reported to inhibit leukotriene activity, reduced allergic airway inflammation and AHR by inhibiting the production of the Th2 cytokines IL-4 and IL-5, and RANTES.
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Asma/tratamiento farmacológico , Hiperreactividad Bronquial/tratamiento farmacológico , Petasites/química , Fitoterapia , Extractos Vegetales/farmacología , Células Th2/efectos de los fármacos , Animales , Asma/inmunología , Asma/fisiopatología , Hiperreactividad Bronquial/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Quimiocina CCL5/inmunología , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Peroxidasa del Eosinófilo/inmunología , Eosinófilos/inmunología , Inmunoglobulina E/sangre , Interleucina-4/inmunología , Interleucina-5/inmunología , Ratones , Ratones Endogámicos BALB C , Moco/inmunología , Ovalbúmina , Células Th2/inmunologíaRESUMEN
Calcium L-methylfolate (L-5-MTHF-Ca; CAS Number 151533-22-1) is a source of folate and an alternative to folic acid for use in human food and food supplements. The safety of L-5-MTHF-Ca was evaluated by testing for genotoxicity, subchronic and prenatal developmental toxicity. In in vitro assays L-5-MTHF-Ca was not mutagenic and did not induce other chromosomal events. Additionally, L-5-MTHF-Ca was not genotoxic in the in vivo micronucleus test nor did it induce DNA damage in rat liver cells. In a subchronic toxicity study, rats administered up to 400â¯mg/kg bw/day of L-5-MTHF-Ca via oral gavage for 13 weeks had no treatment-related mortalities, and no treatment-related effects were identified on behaviour, body weight, food consumption, ophthalmology, haematology, or organ weights. No treatment-related macroscopic or histopathological findings were observed. Calcium and sodium levels increased with increasing dosage, however the slight increases were within historical control ranges and reversible after the recovery period. L-5-MTHF-Ca is neither teratogenic nor embryotoxic. Based on the results of the in vitro and in vivo studies, the safe use of L-5-MTHF-Ca as an ingredient in foods is supported. The no observed adverse effect level was the highest dose in the subchronic toxicity study, i.e. 400â¯mg/kg bw/day for male and female rats.
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OBJECTIVES: This paper studies A. probatocephalus teeth and investigates the mechanical properties and chemical composition of the enameloid and dentin. DESIGN: Nanoindentation tests with a max load of 1000⯵N and X-ray Energy Dispersive Spectroscopy (EDS) were performed along the diameter of the polished sample. Microstructural analysis of the dentin tubules was performed from SEM images. RESULTS: From nanoindentation testing, the dentin of the sheepshead teeth has a nanoindentation hardness of 0.89⯱â¯0.21 (mean⯱â¯S.D.) GPa and a reduced Young's modulus of 23.29⯱â¯5.30â¯GPa. The enameloid of A. probatocephalus has a hardness of 4.36⯱â¯0.44â¯GPa and a mean reduced Young's modulus of 98.14⯱â¯6.91â¯GPa. Additionally, nanoindentation tests showed that the enameloid's hardness and modulus increased closer to the surface of the tooth. X-ray Energy Dispersive Spectroscopy (EDS) data further suggests that the gradient may be a result of the wt% fluoride within the enameloid, where an increase in fluoride results in an increase in reduced Young's modulus and hardness. CONCLUSION: The microstructural characterization of the number density and area of the dentin tubules were used to address the porosity effect in the dentin to achieve the experimentally validated microhardness. The mechanical properties of the sheepshead teeth were also compared with previous nanoindentation tests from other aquatic species. The sheepshead teeth exhibit a greater reduced Young's modulus and hardness compared to shark and piranha teeth.
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Dentina/química , Dentina/ultraestructura , Peces/anatomía & histología , Diente/química , Diente/ultraestructura , Animales , Fenómenos Biomecánicos , Esmalte Dental/química , Esmalte Dental/diagnóstico por imagen , Esmalte Dental/efectos de los fármacos , Análisis del Estrés Dental , Dentina/diagnóstico por imagen , Dentina/efectos de los fármacos , Módulo de Elasticidad , Fluoruros/farmacología , Dureza , Estrés Mecánico , Diente/diagnóstico por imagen , Diente/efectos de los fármacosRESUMEN
Despite the fact that a series of endogenous and exogenous inflammatory mediators are potent activators of circulating granulocytes, damage of vascular endothelium, a primary target tissue, is a rather unusual event in systemic inflammatory states. Since mediator-induced neutrophil hyperadhesiveness on plastic tissue culture dishes is invariably accompanied by intense release of lysosomal granule constituents and respiratory burst activation, thus representing a powerful model to investigate neutrophil cytotoxic states, comparative studies with neutrophils suspended in autologous plasma in the presence or absence of N-formyl-Met-Leu-Phe (2.5 microM), the most potent adhesion inducer, were performed on different biologic surfaces. On optimally adherent closed monolayers of cultured endothelial cells or fibroblasts we observed poor stimulation of adhesion as well as minimal granule release and hexose monophosphate pathway activation. Functional behavior of neutrophils on single molecular components of basal laminas such as fibronectin and collagen (type IV) coats was intermediate, with positive adhesion promotion but markedly reduced metabolic activation. When tested on endothelial cell-derived extracellular matrices, neutrophils again showed functional nonresponsiveness to N-formyl-Met-Leu-Phe. Scanning electron microscopy revealed an impressive congruency between the degree of cellular spreading and metabolic activation in the presence of N-formyl-Met-Leu-Phe, with maximally flattened neutrophils on plastic vs. nonspread, polarized cells on monolayers. Identical results were obtained by using other adhesion inducers such as complement-activated plasma or endotoxin. Lack of cell injury by N-formyl-Met-Leu-Phe-exposed neutrophils was corroborated by the absence of tracer release from [111In]tropolonate-labeled endothelium. These results indicate that biologic surfaces possess antiadhesive properties that protect them from cytotoxic damage by stimulated angry phagocytes.
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Granulocitos/citología , Adhesión Celular , Colágeno/farmacología , Endotelio/citología , Matriz Extracelular/ultraestructura , Femenino , Fibronectinas/farmacología , Humanos , Microscopía Electrónica de Rastreo , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/citología , Embarazo , Propiedades de Superficie , Venas Umbilicales/citologíaRESUMEN
In an attempt to understand the regulatory mechanisms governing passage of neutrophils from the vascular bed to the interstitial tissue, we analyzed the effect of the pleiotropic monokines interleukin 1 (IL-1) and tumor necrosis factor (TNF) on transendothelial neutrophil traffic. Short-time preincubation of human umbilical vein endothelial cell (HUVE) monolayers with IL-1 and TNF led to an impressive time- and dose-dependent increase of endothelial cell-associated neutrophils when working in a full plasma system on petri dishes. Electron microscopic analysis revealed junctional penetration of monolayers by neutrophils. More quantitatively, when using a monolayer-on-filter-system, priming led to a severalfold increase in complete layer passage occurring in the absence of an external chemotactic gradient. Direct comparison with an upside-down modification of the system together with data demonstrating the vectorial behavior of such migration revealed that IL-1-stimulated transendothelial neutrophil traffic is polarized. The described enhancement of neutrophil transendothelial passage was found to be a unique feature of IL-1/TNF-activated HUVE since HUVE-dependent transmigration potentiation was not observed as a consequence of mere neutrophil attachment to endothelial cells (e.g., induced by Fc-mediated adherence of PMN to HUVE). IL-1 acts selectively on endothelial cells as demonstrated by total inhibition of its effect by actinomycin D. Moreover, IL-1 does not induce HUVE monolayers to secrete a chemotaxin, and the neutrophil passage guiding principle is removable from the HUVE surface by short trypsin exposure. Congruent results were obtained with human adult arterial as well as saphenous vein endothelial cells. As shown by blockade of neutrophil migration with pertussis toxin, IL-1- and TNF-inducible transendothelial migration can be dissected into an initial anchoring step, which is succeeded by active neutrophil migration, possibly along a putative endothelial membrane-bound gradient.
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Endotelio Vascular/efectos de los fármacos , Interleucina-1/farmacología , Neutrófilos , Factor de Necrosis Tumoral alfa/farmacología , Adhesión Celular , Movimiento Celular , Células Cultivadas , Endotelio Vascular/ultraestructura , Humanos , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Microscopía de Contraste de Fase , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/ultraestructuraRESUMEN
A cornyeform bacterium was isolated from a blood culture from a 24-year-old man with familial hypertrophic non-obstructive cardiomyopathy, chronic abuse of anabolic steroids and prior admission to hospital because of clinical signs of sepsis. 16S rRNA gene analysis unambiguously identified Gordonia terrae.
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Bacteriemia/microbiología , Bacteria Gordonia/aislamiento & purificación , Infecciones Relacionadas con Prótesis/microbiología , Infecciones por Actinomycetales/tratamiento farmacológico , Infecciones por Actinomycetales/microbiología , Adulto , Cateterismo , Bacteria Gordonia/química , Bacteria Gordonia/clasificación , Bacteria Gordonia/genética , Humanos , Masculino , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genéticaRESUMEN
We have developed a widely applicable functional genomics strategy based on alphavirus expression vectors. The technology allows for rapid identification of genes encoding a functional activity such as binding of a defined ligand. Complementary DNA (cDNA) libraries were expressed in mammalian cells following infection with recombinant Sindbis virus (SIN replicon particles), a member of the Alphavirus genus. Virus-infected cells that specifically bound a ligand of choice were isolated using fluorescence-activated cell sorting (FACS). Replication-competent, infective SIN replicon particles harboring the corresponding cDNA were amplified in a next step. Within one round of selection, viral clones encoding proteins recognized by monoclonal antibodies or Fc-fusion molecules could be isolated and sequenced. Moreover, using the same viral libraries, a plaque-lift assay was established that allowed the identification of secreted, intracellular, and membrane proteins.