942 resultados para dyes, reagents, indicators, markers and buffers


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Local rates of change in ice-sheet thickness were calculated at IS sites in West Antarctica using the submergence velocity technique. This method entails a comparison of the vertical velocity of the ice sheet, measured using repeat global positioning system surveys of markers, and local long-term rates of snow accumulation obtained using firn-core stratigraphy. Any significant difference between these two quantities represents a thickness change with time. Measurements were conducted at sites located similar to 100-200 km apart along US ITASE traverse routes, and at several isolated locations. All but one of the sites are distributed in the Siple Coast and the Amundsen Sea basin along contours of constant elevation, along flowlines, across ice divides and close to regions of enhanced flow. Calculated rates of thickness change are different from site to site. Most of the large rates of change in ice thickness (similar to 10 cm a(-1) or larger) are observed in or close to regions of rapid flow, and are probably related to ice-dynamics effects. Near-steady-state conditions are calculated mostly at sites in the slow-moving ice-sheet interior and near the main West Antarctic ice divide. These results are consistent with regional estimates of ice-sheet change derived from remote-sensing measurements at similar locations in West Antarctica.

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BACKGROUND The number of cells positive for the α-6 and α-2 integrin subunits and the c-Met receptor in primary tumors and bone biopsies from prostate cancer patients has been correlated with metastasis and disease progression. The objective of this study was to quantify disseminated tumour cells present in bone marrow in prostate cancer patients using specific markers and determine their correlation with metastasis and survival. METHODS Patients were included at different stage of prostate cancer disease, from localised to metastatic castration-resistant prostate cancer. Healthy men were used as a control group. Bone marrow samples were collected and nucleated cells separated. These were stained for CD45, α-2, α-6 integrin subunits and c-Met and samples were processed for analysis and quantification of CD45-/α2+/α6+/c-met + cells using flow cytometry. Clinical and pathological parameters were assessed and survival measured. Statistical analyses were made of associations between disease specific parameters, bone marrow flow cytometry data, prostate-specific antigen (PSA) progression free survival and bone metastases progression free survival. RESULTS For all markers, the presence of more than 0.1% positive cells in bone marrow aspirates was significantly associated with the risk of biochemical progression, the risk of developing metastasis and death from prostate cancer. CONCLUSIONS Quantification of cells carrying putative stem cell markers in bone marrow is a potential indicator of disease progression. Functional studies on isolated cells are needed to show more specifically their property for metastatic spread in prostate cancer.

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Radiocarbon (14C) analysis is a unique tool to distinguish fossil/nonfossil sources of carbonaceous aerosols. We present 14C measurements of organic carbon (OC) and total carbon (TC) on highly time resolved filters (3–4 h, typically 12 h or longer have been reported) from 7 days collected during California Research at the Nexus of Air Quality and Climate Change (CalNex) 2010 in Pasadena. Average nonfossil contributions of 58% ± 15% and 51% ± 15% were found for OC and TC, respectively. Results indicate that nonfossil carbon is a major constituent of the background aerosol, evidenced by its nearly constant concentration (2–3 μgC m−3). Cooking is estimated to contribute at least 25% to nonfossil OC, underlining the importance of urban nonfossil OC sources. In contrast, fossil OC concentrations have prominent and consistent diurnal profiles, with significant afternoon enhancements (~3 μgC m−3), following the arrival of the western Los Angeles (LA) basin plume with the sea breeze. A corresponding increase in semivolatile oxygenated OC and organic vehicular emission markers and their photochemical reaction products occurs. This suggests that the increasing OC is mostly from fresh anthropogenic secondary OC (SOC) from mainly fossil precursors formed in the western LA basin plume. We note that in several European cities where the diesel passenger car fraction is higher, SOC is 20% less fossil, despite 2–3 times higher elemental carbon concentrations, suggesting that SOC formation from gasoline emissions most likely dominates over diesel in the LA basin. This would have significant implications for our understanding of the on-road vehicle contribution to ambient aerosols and merits further study.

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Mast cells (MCs) are well known for their neoplastic transformation in solitary and multiple cutaneous mast cell tumours (MCTs), as well as visceral and systemic mastocytosis. Dogs have a unique risk of developing cutaneous MCTs, and they account for 7% to 21% of all canine skin tumours. The aetiology of canine MCTs is unknown but is probably multifactorial. This article reviews up-to-date knowledge on the pathogenesis, the clinical presentation, the clinical prognostic factors, the diagnostic workup including clinical staging, cytological findings, histological findings and the various grading systems which have been evaluated based on morphology, the assessment of proliferation markers and other factors such as vessel density. Furthermore, detailed information about current treatment protocols for canine cutaneous MCTs is provided.

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Fibromuscular dysplasia (FMD) is a rare, nonatherosclerotic arterial disease for which the molecular basis is unknown. We comprehensively studied 47 subjects with FMD, including physical examination, spine magnetic resonance imaging, bone densitometry, and brain magnetic resonance angiography. Inflammatory biomarkers in plasma and transforming growth factor β (TGF-β) cytokines in patient-derived dermal fibroblasts were measured by ELISA. Arterial pathology other than medial fibrodysplasia with multifocal stenosis included cerebral aneurysm, found in 12.8% of subjects. Extra-arterial pathology included low bone density (P<0.001); early onset degenerative spine disease (95.7%); increased incidence of Chiari I malformation (6.4%) and dural ectasia (42.6%); and physical examination findings of a mild connective tissue dysplasia (95.7%). Screening for mutations causing known genetically mediated arteriopathies was unrevealing. We found elevated plasma TGF-β1 (P=0.009), TGF-β2 (P=0.004) and additional inflammatory markers, and increased TGF-β1 (P=0.0009) and TGF-β2 (P=0.0001) secretion in dermal fibroblast cell lines from subjects with FMD compared to age- and gender-matched controls. Detailed phenotyping of patients with FMD allowed us to demonstrate that FMD is a systemic disease with alterations in common with the spectrum of genetic syndromes that involve altered TGF-β signaling and offers TGF-β as a marker of FMD.

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OBJECTIVES To summarize the current status of clinicopathological and molecular markers for the prediction of recurrence or progression or both in non-muscle-invasive and survival in muscle-invasive urothelial bladder cancer, to address the reproducibility of pathology and molecular markers, and to provide directions toward implementation of molecular markers in future clinical decision making. METHODS AND MATERIALS Immunohistochemistry, gene signatures, and FGFR3-based molecular grading were used as molecular examples focussing on prognostics and issues related to robustness of pathological and molecular assays. RESULTS The role of molecular markers to predict recurrence is limited, as clinical variables are currently more important. The prediction of progression and survival using molecular markers holds considerable promise. Despite a plethora of prognostic (clinical and molecular) marker studies, reproducibility of pathology and molecular assays has been understudied, and lack of reproducibility is probably the main reason that individual prediction of disease outcome is currently not reliable. CONCLUSIONS Molecular markers are promising to predict progression and survival, but not recurrence. However, none of these are used in the daily clinical routine because of reproducibility issues. Future studies should focus on reproducibility of marker assessment and consistency of study results by incorporating scoring systems to reduce heterogeneity of reporting. This may ultimately lead to incorporation of molecular markers in clinical practice.

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BackgroundHepatorenal tyrosinaemia (Tyr 1) is a rare inborn error of tyrosine metabolism. Without treatment, patients are at high risk of developing acute liver failure, renal dysfunction and in the long run hepatocellular carcinoma. The aim of our study was to collect cross-sectional data.MethodsVia questionnaires we collected retrospective data of 168 patients with Tyr 1 from 21 centres (Europe, Turkey and Israel) about diagnosis, treatment, monitoring and outcome. In a subsequent consensus workshop, we discussed data and clinical implications.ResultsEarly treatment by NTBC accompanied by diet is essential to prevent serious complications such as liver failure, hepatocellular carcinoma and renal disease. As patients may remain initially asymptomatic or develop uncharacteristic clinical symptoms in the first months of life newborn mass screening using succinylacetone (SA) as a screening parameter in dried blood is mandatory for early diagnosis. NTBC-treatment has to be combined with natural protein restriction supplemented with essential amino acids. NTBC dosage should be reduced to the minimal dose allowing metabolic control, once daily dosing may be an option in older children and adults in order to increase compliance. Metabolic control is judged by SA (below detection limit) in dried blood or urine, plasma tyrosine (<400 ¿M) and NTBC-levels in the therapeutic range (20¿40 ¿M). Side effects of NTBC are mild and often transient.Indications for liver transplantation are hepatocellular carcinoma or failure to respond to NTBC. Follow-up procedures should include liver and kidney function tests, tumor markers and imaging, ophthalmological examination, blood count, psychomotor and intelligence testing as well as therapeutic monitoring (SA, tyrosine, NTBC in blood).ConclusionBased on the data from 21 centres treating 168 patients we were able to characterize current practice and clinical experience in Tyr 1. This information could form the basis for clinical practice recommendations, however further prospective data are required to underpin some of the recommendations.

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BACKGROUND AND AIMS The structured IBD Ahead 'Optimised Monitoring' programme was designed to obtain the opinion, insight and advice of gastroenterologists on optimising the monitoring of Crohn's disease activity in four settings: (1) assessment at diagnosis, (2) monitoring in symptomatic patients, (3) monitoring in asymptomatic patients, and (4) the postoperative follow-up. For each of these settings, four monitoring methods were discussed: (a) symptom assessment, (b) endoscopy, (c) laboratory markers, and (d) imaging. Based on literature search and expert opinion compiled during an international consensus meeting, recommendations were given to answer the question 'which diagnostic method, when, and how often'. The International IBD Ahead Expert Panel advised to tailor this guidance to the healthcare system and the special prerequisites of each country. The IBD Ahead Swiss National Steering Committee proposes best-practice recommendations adapted for Switzerland. METHODS The IBD Ahead Steering Committee identified key questions and provided the Swiss Expert Panel with a structured literature research. The expert panel agreed on a set of statements. During an international expert meeting the consolidated outcome of the national meetings was merged into final statements agreed by the participating International and National Steering Committee members - the IBD Ahead 'Optimized Monitoring' Consensus. RESULTS A systematic assessment of symptoms, endoscopy findings, and laboratory markers with special emphasis on faecal calprotectin is deemed necessary even in symptom-free patients. The choice of recommended imaging methods is adapted to the specific situation in Switzerland and highlights the importance of ultrasonography and magnetic resonance imaging besides endoscopy. CONCLUSION The recommendations stress the importance of monitoring disease activity on a regular basis and by objective parameters, such as faecal calprotectin and endoscopy with detailed documentation of findings. Physicians should not rely on symptoms only and adapt the monitoring schedule and choice of options to individual situations.

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BACKGROUND Cell-free foetal haemoglobin (HbF) has been shown to play a role in the pathology of preeclampsia (PE). In the present study, we aimed to further characterize the harmful effects of extracellular free haemoglobin (Hb) on the placenta. In particular, we investigated whether cell-free Hb affects the release of placental syncytiotrophoblast vesicles (STBMs) and their micro-RNA content. METHODS The dual ex-vivo perfusion system was used to perfuse isolated cotyledons from human placenta, with medium alone (control) or supplemented with cell-free Hb. Perfusion medium from the maternal side of the placenta was collected at the end of all perfusion phases. The STBMs were isolated using ultra-centrifugation, at 10,000×g and 150,000×g (referred to as 10K and 150K STBMs). The STBMs were characterized using the nanoparticle tracking analysis, identification of surface markers and transmission electron microscopy. RNA was extracted and nine different micro-RNAs, related to hypoxia, PE and Hb synthesis, were selected for analysis by quantitative PCR. RESULTS All micro-RNAs investigated were present in the STBMs. Mir-517a, mir-141 and mir-517b were down regulated after Hb perfusion in the 10K STBMs. Furthermore, Hb was shown to be carried by the STBMs. CONCLUSION This study showed that Hb perfusion can alter the micro-RNA content of released STBMs. Of particular interest is the alteration of two placenta specific micro-RNAs; mir-517a and mir-517b. We have also seen that STBMs may function as carriers of Hb into the maternal circulation.

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The genetic structure and dynamics of hybrid zones provide crucial information for understanding the processes and mechanisms of evolutionary divergence and speciation. In general, higher levels of evolutionary divergence between taxa are more likely to be associated with reproductive isolation and may result in suppressed or strongly restricted hybridization. In this study, we examined two secondary contact zones between three deep evolutionary lineages in the common vole (Microtus arvalis). Differences in divergence times between the lineages can shed light on different stages of reproductive isolation and thus provide information on the ongoing speciation process in M. arvalis. We examined more than 800 individuals for mitochondrial (mtDNA), Y-chromosome and autosomal markers and used assignment and cline analysis methods to characterize the extent and direction of gene flow in the contact zones. Introgression of both autosomal and mtDNA markers in a relatively broad area of admixture indicates selectively neutral hybridization between the least-divergent lineages (Central and Eastern) without evidence for partial reproductive isolation. In contrast, a very narrow area of hybridization, shifts in marker clines and the quasi-absence of Y-chromosome introgression support a moving hybrid zone and unidirectional selection against male hybrids between the lineages with older divergence (Central and Western). Data from a replicate transect further support non-neutral processes in this hybrid zone and also suggest a role for landscape history in the movement and shaping of geneflow profiles.

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Treatment allocation by epidermal growth factor receptor mutation status is a new standard in patients with metastatic nonesmall-cell lung cancer. Yet, relatively few modern chemotherapy trials were conducted in patients characterized by epidermal growth factor receptor wild type. We describe the results of a multicenter phase II trial, testing in parallel 2 novel combination therapies, predefined molecular markers, and tumor rebiopsy at progression. Objective: The goal was to demonstrate that tailored therapy, according to tumor histology and epidermal growth factor receptor (EGFR) mutation status, and the introduction of novel drug combinations in the treatment of advanced nonesmall-cell lung cancer are promising for further investigation. Methods: We conducted a multicenter phase II trial with mandatory EGFR testing and 2 strata. Patients with EGFR wild type received 4 cycles of bevacizumab, pemetrexed, and cisplatin, followed by maintenance with bevacizumab and pemetrexed until progression. Patients with EGFR mutations received bevacizumab and erlotinib until progression. Patients had computed tomography scans every 6 weeks and repeat biopsy at progression. The primary end point was progression-free survival (PFS) ≥ 35% at 6 months in stratum EGFR wild type; 77 patients were required to reach a power of 90% with an alpha of 5%. Secondary end points were median PFS, overall survival, best overall response rate (ORR), and tolerability. Further biomarkers and biopsy at progression were also evaluated. Results: A total of 77 evaluable patients with EGFR wild type received an average of 9 cycles (range, 1-25). PFS at 6 months was 45.5%, median PFS was 6.9 months, overall survival was 12.1 months, and ORR was 62%. Kirsten rat sarcoma oncogene mutations and circulating vascular endothelial growth factor negatively correlated with survival, but thymidylate synthase expression did not. A total of 20 patients with EGFR mutations received an average of 16.

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Przewalski's horses (PHs, Equus ferus ssp. przewalskii) were discovered in the Asian steppes in the 1870s and represent the last remaining true wild horses. PHs became extinct in the wild in the 1960s but survived in captivity, thanks to major conservation efforts. The current population is still endangered, with just 2,109 individuals, one-quarter of which are in Chinese and Mongolian reintroduction reserves [1]. These horses descend from a founding population of 12 wild-caught PHs and possibly up to four domesticated individuals [2-4]. With a stocky build, an erect mane, and stripped and short legs, they are phenotypically and behaviorally distinct from domesticated horses (DHs, Equus caballus). Here, we sequenced the complete genomes of 11 PHs, representing all founding lineages, and five historical specimens dated to 1878-1929 CE, including the Holotype. These were compared to the hitherto-most-extensive genome dataset characterized for horses, comprising 21 new genomes. We found that loci showing the most genetic differentiation with DHs were enriched in genes involved in metabolism, cardiac disorders, muscle contraction, reproduction, behavior, and signaling pathways. We also show that DH and PH populations split ∼45,000 years ago and have remained connected by gene-flow thereafter. Finally, we monitor the genomic impact of ∼110 years of captivity, revealing reduced heterozygosity, increased inbreeding, and variable introgression of domestic alleles, ranging from non-detectable to as much as 31.1%. This, together with the identification of ancestry informative markers and corrections to the International Studbook, establishes a framework for evaluating the persistence of genetic variation in future reintroduced populations.

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OBJECTIVE: To evaluate serum concentrations of biochemical markers and survival time in dogs with protein-losing enteropathy (PLE). DESIGN: Prospective study. ANIMALS: 29 dogs with PLE and 18 dogs with food-responsive diarrhea (FRD). PROCEDURES: Data regarding serum concentrations of various biochemical markers at the initial evaluation were available for 18 of the 29 dogs with PLE and compared with findings for dogs with FRD. Correlations between biochemical marker concentrations and survival time (interval between time of initial evaluation and death or euthanasia) for dogs with PLE were evaluated. RESULTS: Serum C-reactive protein concentration was high in 13 of 18 dogs with PLE and in 2 of 18 dogs with FRD. Serum concentration of canine pancreatic lipase immunoreactivity was high in 3 dogs with PLE but within the reference interval in all dogs with FRD. Serum α1-proteinase inhibitor concentration was less than the lower reference limit in 9 dogs with PLE and 1 dog with FRD. Compared with findings in dogs with FRD, values of those 3 variables in dogs with PLE were significantly different. Serum calprotectin (measured by radioimmunoassay and ELISA) and S100A12 concentrations were high but did not differ significantly between groups. Seventeen of the 29 dogs with PLE were euthanized owing to this disease; median survival time was 67 days (range, 2 to 2,551 days). CONCLUSIONS AND CLINICAL RELEVANCE: Serum C-reactive protein, canine pancreatic lipase immunoreactivity, and α1-proteinase inhibitor concentrations differed significantly between dogs with PLE and FRD. Most initial biomarker concentrations were not predictive of survival time in dogs with PLE.

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Question: Low back pain is an increasing global health problem, which is associated with intervertebral disc (IVD) damage and de- generation. Major changes occur in the nucleus pulposus (NP), with the degradation of the extracellular matrix (ECM) [1]. Further studies showed that growth factors from the transforming growth factor (TGF) and bone morphogenic proteins (BMP) family may induce chondrogenic differentiation of mesenchymal stem cells (MSC) [2]. Focusing on non-viral gene therapies and their possible translation into the clinics, we investigated if GDF6 (syn. BMP13 or CDMP2) can induce regeneration of degraded NP. We hypothesized that IVD transfected with plasmid over-expressing GDF6 also up-regulates other NP- and chondrogenic cell markers and enhances ECM deposition. Methods: Bovine IVD cells were isolated by pronase/collagenase II overnight digestion. After monolayer expansion up to passage 3, cells were transfected with the plasmid pGDF6 (RG211366, Origene, SF) or with green fluorescence protein (GFP) control using the NeonÒ transfection system (Invitrogen, Basel), both equipped with a Cy- tomegalovirus (CMV) promotor to induce over-expression. We tested a range of yet unpublished parameters for each of the primary disc cells to optimize efficiency. To test a non-viral gene therapy applied directly to 3D whole organ culture, bovine IVDs were harvested from fresh tails obtained from the abattoir within 5 h post-mortem [3]. Discs were then pre-incubated for 24 h in high glucose Dulbecco’s Modified Eagle Medium and 5 % fetal calf serum. Each disc was transfected by injection of 5 lg of plasmid GDF6 (Origene, RG211366) into the center by 25G needle and using Hamilton sy- ringe. Electroporation was performed using 2-needle array electrode or tweezertrodes; 8 pulses at 200mv/cm with an interval of 10 ms were applied using ECM830 Square Wave Electroporation System (Harvard Apparatus, MA) (Fig. 1). After transfection discs were cultured for 72 h to allow expression of GFP or GDF6. Discs were then fixed, cryosectioned and analysed by immunofluorescence against GDF6. Results: We successfully transfected bovine NP and AF cells in monolayer culture with the two plasmids using a 1,400 V, 20 ms and 2 pulses with a *25 % efficiency using 0.15 M cells and 3 lg DNA (Fig. 1). Organ IVD culture transfection revealed GFP6 positive staining in the centre of the disc using 2-needle array electrode. Results from tweezertrodes did not show any GFP posi- tive cells. Conclusions: We identified novel parameters to successfully transfect primary bovine IVD cells. For transfection of whole IVD explants electroporation parameters need to be further optimized. Acknowledgments: This study was supported by the Lindenhof Foundation ‘‘Forschung und Lehre’’ (Project no. 13-02-F). References 1. Roughly PJ (2004) Spine (Phila) 29:2691–2699 2. 3. Clarke LE, McConell JC, Sherratt MJ, Derby B, Richardson SM, Hoyland JA (2014) Arthritis Res Ther 16:R67 Chan SC, Gantenbein-Ritter B (2012) J Vis Exp 60(60):e3490

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Kosrae is the most remote island of the Federated States of Micronesia (FSM), with a population of less than 7,000 inhabitants, located in the Pacific Ocean between Hawaii and Guam. FSM is an independent sovereign nation consisting of four states in total: Pohnpei, Chuuk, Yap, and Kosrae. Having passed through the hands of Spain, Germany and Japan, the United States gained administrative control of FSM after WWII, as commissioned by the UN. The FSM became an independent nation in 1986 while still retaining affiliation with the US under a ‘Compact of Free Association’. Now both Kosraean and English are considered to be the two official languages and the variety of Kosraean English which has arisen proves for an interesting comparative study. In order to obtain the relevant data, I spent three months on the island of Kosrae, interviewing 90 local speakers, ranging in age (16-70), occupation, sex and time spent off island. The 45 minute long interviews were informal but supported by participant information to capture relevant data and conversations were guided in a way that aimed to reveal language and cultural attitudes. With reference to these samples, I examine the effects of American English on the language use in Kosrae. This paper aims to present a broad analysis of phonological, morphosyntactic and pragmatic features, such as pro-dropping, discourse markers and other practices in order to demonstrate the similarities and differences between the two varieties, which are coming to shape the variety developing on Kosrae. Having transcribed conversations using the tool Elan, I will put particular focus on [h] deletion and insertion, a rare occurrence found in a variety of post-colonial American English which I believe is of particular interest. I assess the presence of English in Kosrae with reference to sociological influences, past and present. First, I discuss the extralinguistic factors which have shaped the English that is currently used on Kosrae, including migration between US and FSM, and English as a language of administration, social media usage and visual media presence. Secondly, I assess the use of English in this community in light of Schneider’s (2007) ‘Dynamic Model’, with reference to America’s contribution as an ‘exploitation colony’ as defined by Mufwene (2001). Finally, an overview of the salient linguistic characteristics of Kosraean English, based on the data collected will be presented and compared to features associated with standard American English in view of examining overlap and divergence. The overall objective is to present a cross-linguistic description of a hitherto unexamined English emerging in a postcolonial environment with a juxtaposed contact variety. Mufwene, Salikoko S. 2001. The ecology of language evolution. Cambridge: Cambridge University Press. Schneider, E. (2007). Postcolonial Englishes. Cambridge: Cambridge University Press. Segal, H.G. (1989) Kosrae, The Sleeping Lady Awakens. Kosrae: Kosrae Tourist Division, Dept. Of Conservation and Development. Keywords: American English, Global English, Pacific English, Morphosyntactic, Phonological, Variation, Discourse