272 research outputs found
Skeletal Plasmacytoma: Progression of disease and impact of local treatment; an analysis of SEER database
<p>Abstract</p> <p>Background</p> <p>Previous reports suggest an as yet unidentifiable subset of patients with plasmacytoma will progress to myeloma. The current study sought to establish the risk of developing myeloma and determine the prognostic factors affecting the progression of disease.</p> <p>Methods</p> <p>Patients with plasmacytoma diagnosed between 1973 and 2005 were identified in the SEER database(1164 patients). Patient demographics and clinical characteristics, treatment(s), cause of death, and survival were extracted. Kaplan-Meier, log-rank, and Cox regression were used to analyze prognostic factors.</p> <p>Results</p> <p>The five year survival among patients initially diagnosed with plasmacytoma that later progressed to multiple myeloma and those initially diagnosed with multiple myeloma were almost identical (25% and 23%; respectively). Five year survival for patients with plasmacytoma that did not progress to multiple myeloma was significantly better (72%). Age > 60 years was the only factor that correlated with progression of disease (p = 0.027).</p> <p>Discussion</p> <p>Plasmacytoma consists of two cohorts of patients with different overall survival; those patients that do not progress to systemic disease and those that develop myeloma. Age > 60 years is associated with disease progression. Identifying patients with systemic disease early in the treatment will permit aggressive and novel treatment strategies to be implemented.</p
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Rietveld-based quantitative phase analysis of sugars in confectionery
Sugars are a near-ubiquitous ingredient in food products, yet rising rates of obesity and related illnesses have prompted a drive to reduce their content. The use of amorphous sugars in confectionery may be one way of achieving this by providing a similarly sweet sensation due to increased dissolution rate. However, accurate amorphous and crystalline form characterisation and quantification of complex foodstuffs can be difficult.
In this study, a method for the quantification of crystalline and amorphous sugars in chocolate precursors, using powder X ray powder diffraction, is presented. The method was first validated by the use of known compositions of mixtures of amorphous and crystalline sugars, then employed in assessing two chocolate crumb samples. The results show that the method can reliably determine the absolute quantity of amorphous and crystalline components in a confectionery sample, whilst maintaining sample integrity, apart from the addition of an inert internal standard. As such, it is a valuable addition to other techniques currently used
Study of mass and momentum transfer in diesel sprays base on X-ray mass distribution measurements and on a theoretical derivation
[EN] In this paper, a research aimed at quantifying mass and momentum transfer in the near-nozzle field of diesel sprays injected into stagnant ambient air is reported. The study combines X-ray measurements for two different nozzles and axial positions, which provide mass distributions in the spray, with a theoretical model based on momentum flux conservation, which was previously validated. This investigation has allowed the validation of Gaussian profiles for local fuel concentration and velocity near the nozzle exit, as well as the determination of Schmidt number at realistic diesel spray conditions. This information could be very useful for those who are interested in spray modeling, especially at high-pressure injection conditions. © 2010 Springer-Verlag.This work was partly sponsored by "Vicerrectorado de Investigacion, Desarrollo e Innovacion'' of the "Universidad Politecnica de Valencia'' in the frame of the project "Estudio del flujo en el interior de toberas de inyeccion Diesel'', reference no. 3150 and by "Generalitat Valenciana'' in the frame of the project with the same title and reference GV/2009/031. This support is gratefully acknowledged by the authors.Desantes, J.; Salvador Rubio, FJ.; López, JJ.; De La Morena, J. (2011). Study of mass and momentum transfer in diesel sprays base on X-ray mass distribution measurements and on a theoretical derivation. Experiments in Fluids. 50(2):233-246. https://doi.org/10.1007/s00348-010-0919-8S233246502Abramovich GN (1963) The theory of turbulent jets. MIT Press, Cambridge, MAAdler D, Lyn WT (1969) The evaporation and mixing of a liquid fuel spray in a Diesel air swirl. Proc Instn Mech Eng 184:171–180Coghe A, Cossali GE (1994) Phase Doppler characterisation of a Diesel spray injected into a high density gas under vaporisation regimes. In: 7th international symposium on application of laser techniques to fluid mechanics, LisbonCorreas D (1998) Theoretical and experimental study of isothermal Diesel free sprays (in Spanish). PhD Thesis, Universidad Politécnica de ValenciaCossali GE (2001) An integral model for gas entrainment into full cone sprays. J Fluid Mech 439:353–366Dent JC (1971) A basis for the comparison of various experimental methods for studying spray penetration. SAE Paper 710571Desantes JM, Payri R, Salvador FJ, Gil A (2006a) Deduction and validation of a theoretical model for a free diesel Spray. Fuel 85:910–917Desantes JM, Arrègle J, López JJ, Cronhjort A (2006b) Scaling laws for free turbulent gas jets and Diesel-like sprays. Atomization Spray 16:443–473Desantes JM, Payri R, García JM, Salvador FJ (2007) A contribution to the understanding of isothermal diesel spray dynamics. Fuel 86:1093–1101Dumouchel C (2008) On the experimental investigation on primary atomization of liquid streams. Exp Fluids 45:371–422Heimgärtner C, Leipertz A (2000) of the primary spray break-up close to the nozzle of a common-rail high pressure diesel injection system. SAE Paper 2000-01-1799Hinze JO (1975) Turbulence. McGraw Hill, New YorkHiroyasu H, Arai M (1990) Structures of fuel sprays in diesel engines. SAE Paper 900475Jawad B, Gulari E, Henein NA (1992) Characteristics of intermittent fuel sprays. Combust Flame 88:384–396Lefèbvre AH (1989) Atomization and sprays. Hemisphere, New YorkLeick P, Riedel T, Bittlinger G, Powell CF, Kastengren AL, Wang J (2007) X-Ray measurements of the mass distribution in the dense primary break-up region of the spray from a standard multi-hole common-rail diesel injection system. In: Proc 21st ILASS (Europe)Linne M, Paciaroni M, Hall T, Parker T (2006) Ballistic imaging of the near field in a diesel spray. Exp Fluids 40:836–846Naber J, Siebers DL (1996) Effects of gas density and vaporisation on penetration and dispersion of diesel sprays. SAE Paper 960034Payri F, Bermúdez V, Payri R, Salvador FJ (2004) The influence of cavitation on the internal flow and the Spray characteristics in diesel injection nozzles. Fuel 83:419–431Payri R, García JM, Salvador FJ, Gimeno J (2005) Using spray momentum flux measurements to understand the influence of diesel nozzle geometry on spray characteristics. Fuel 84:551–561Payri R, Tormos B, Salvador FJ, Araneo L (2008) Spray droplet velocity characterization for convergent nozzles with three different diameters. Fuel 87:3176–3182Post S, Iyer V, Abraham J (2000) A study of near-field entrainment in gas jets and sprays under diesel conditions. ASME J Fluids Eng 122:385–395Prasad CMV, Kar S (1976) An investigation on the diffusion of momentum and mass of fuel in a diesel fuel spray. ASME J Eng Power 76-DGP-1:1–11Rajaratnam N (1976) Turbulent jets. Elsevier, AmsterdamRamirez AI, Som S, Aggarwal SK, Kastengren AL, El-Hannouny EM, Longman DE, Powell CF (2009) Quantitative X-ray measurements of high-pressure fuel sprays from a production heavy duty diesel injector. Exp Fluids 47:119–134Reitz RD, Bracco FV (1982) Mechanism of atomisation of a liquid jet. Phys Fluids 25(10):1730–1742Ricou FP, Spalding DB (1961) Measurements of entrainment by axisymmetrical turbulent jets. J Fluid Mech 11:21–32Rife J, Heywood JB (1974) Photographic and performance studies of diesel combustion with a rapid compression machine. SAE Paper 740948Roisman IV, Tropea C (2001) Flux measurements in sprays using phase doppler techniques. Atomization Spray 11:667–699Roisman IV, Araneo L, Tropea C (2007) Effect of ambient pressure on penetration of a diesel spray. Int J Multiphase Flow 33(8):904–920Saliba R, Baz I, Champoussin JC, Lance M, Marié JL (2004) Cavitation effect on the near nozzle spray development in high-pressure diesel injection. In: Proc 19th ILASS (Europe)Schlichting H (1978) Boundary layer theory. McGraw Hill, New YorkSinnamon JF, Lancaster DR, Stiener JC (1980) An experimental and analytical study of engine fuel spray trajectories. SAE Paper 800135Sou A, Hosokawa S, Tomiyama A (2007) Effects of cavitation in a nozzle on liquid jet atomization. Int J Heat Mass Tran 50(17–18):3575–3582Spalding DB (1979) Combustion and mass transfer. Pergamon Press, New YorkSubramaniam S (2001) Statistical modelling of a spray as using the droplet distribution function. Phys Fluids 13(3):624–642Tanner FX, Feigl A, Ciatti SA, Powell CF, Cheong S-K, Liu J, Wang J (2006) Structure of high-velocity dense sprays in the near-nozzle region. Atomization Spray 16:579–597Way RJB (1977) Investigation of interaction between swirl and jets in direct injection diesel engines using a water model. SAE Paper 770412Wu KJ, Santavicca DA, Bracco FV (1984) LDV measurements of drop velocity in diesel-type sprays. AAIA J 22(9):1263–1270Wu KJ, Reitz RD, Bracco FV (1986) Measurements of drop size at the spray edge near the nozzle in atomising liquid jets. Phys Fluids 29(4):941–951Yue Y, Powell CF, Poola R, Wang J, Schaller JK (2001) Quantitative measurements of diesel fuel spray characteristics in the near-nozzle region using X-ray absorption. Atomization Spray 11(4):471–49
Association between polymorphisms in RMI1, TOP3A, and BLM and risk of cancer, a case-control study
BACKGROUND: Mutations altering BLM function are associated with highly elevated cancer susceptibility (Bloom syndrome). Thus, genetic variants of BLM and proteins that form complexes with BLM, such as TOP3A and RMI1, might affect cancer risk as well. METHODS: In this study we have studied 26 tagged single nucleotide polymorphisms (tagSNPs) in RMI1, TOP3A, and BLM and their associations with cancer risk in acute myeloid leukemia/myelodysplatic syndromes (AML/MDS; N = 152), malignant melanoma (N = 170), and bladder cancer (N = 61). Two population-based control groups were used (N = 119 and N = 156). RESULTS: Based on consistency in effect estimates for the three cancer forms and similar allelic frequencies of the variant alleles in the control groups, two SNPs in TOP3A (rs1563634 and rs12945597) and two SNPs in BLM (rs401549 and rs2532105) were selected for analysis in breast cancer cases (N = 200) and a control group recruited from spouses of cancer patients (N = 131). The rs12945597 in TOP3A and rs2532105 in BLM showed increased risk for breast cancer. We then combined all cases (N = 584) and controls (N = 406) respectively and found significantly increased risk for variant carriers of rs1563634 A/G (AG carriers OR = 1.7 [95%CI 1.1-2.6], AA carriers OR = 1.8 [1.2-2.8]), rs12945597 G/A (GA carriers OR = 1.5 [1.1-1.9], AA carriers OR = 1.6 [1.0-2.5]), and rs2532105 C/T (CT+TT carriers OR = 1.8 [1.4-2.5]). Gene-gene interaction analysis suggested an additive effect of carrying more than one risk allele. For the variants of TOP3A, the risk increment was more pronounced for older carriers. CONCLUSION: These results further support a role of low-penetrance genes involved in BLM-associated homologous recombination for cancer risk
Deciphering the Multifactorial Nature of Acinetobacter baumannii Pathogenicity
Background: Acinetobacter baumannii is an emerging bacterial pathogen that causes a broad array of infections, particularly in hospitalized patients. Many studies have focused on the epidemiology and antibiotic resistance of A. baumannii, but little is currently known with respect to its virulence potential. Methodology/Principal Findings: The aim of this work was to analyze a number of virulence-related traits of four A. baumannii strains of different origin and clinical impact for which complete genome sequences were available, in order to tentatively identify novel determinants of A. baumannii pathogenicity. Clinical strains showed comparable virulence in the Galleria mellonella model of infection, irrespective of their status as outbreak or sporadic strains, whereas a non-human isolate was avirulent. A combined approach of genomic and phenotypic analyses led to the identification of several virulence factors, including exoproducts with hemolytic, phospholipase, protease and iron-chelating activities, as well as a number of multifactorial phenotypes, such as biofilm formation, surface motility and stress resistance, which were differentially expressed and could play a role in A. baumannii pathogenicity. Conclusion/Significance: This work provides evidence of the multifactorial nature of A. baumannii virulence. While A. baumannii clinical isolates could represent a selected population of strains adapted to infect the human host, subpopulations of highly genotypically and phenotypically diverse A. baumannii strains may exist outside the hospita
How long do nosocomial pathogens persist on inanimate surfaces? A systematic review
BACKGROUND: Inanimate surfaces have often been described as the source for outbreaks of nosocomial infections. The aim of this review is to summarize data on the persistence of different nosocomial pathogens on inanimate surfaces. METHODS: The literature was systematically reviewed in MedLine without language restrictions. In addition, cited articles in a report were assessed and standard textbooks on the topic were reviewed. All reports with experimental evidence on the duration of persistence of a nosocomial pathogen on any type of surface were included. RESULTS: Most gram-positive bacteria, such as Enterococcus spp. (including VRE), Staphylococcus aureus (including MRSA), or Streptococcus pyogenes, survive for months on dry surfaces. Many gram-negative species, such as Acinetobacter spp., Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, Serratia marcescens, or Shigella spp., can also survive for months. A few others, such as Bordetella pertussis, Haemophilus influenzae, Proteus vulgaris, or Vibrio cholerae, however, persist only for days. Mycobacteria, including Mycobacterium tuberculosis, and spore-forming bacteria, including Clostridium difficile, can also survive for months on surfaces. Candida albicans as the most important nosocomial fungal pathogen can survive up to 4 months on surfaces. Persistence of other yeasts, such as Torulopsis glabrata, was described to be similar (5 months) or shorter (Candida parapsilosis, 14 days). Most viruses from the respiratory tract, such as corona, coxsackie, influenza, SARS or rhino virus, can persist on surfaces for a few days. Viruses from the gastrointestinal tract, such as astrovirus, HAV, polio- or rota virus, persist for approximately 2 months. Blood-borne viruses, such as HBV or HIV, can persist for more than one week. Herpes viruses, such as CMV or HSV type 1 and 2, have been shown to persist from only a few hours up to 7 days. CONCLUSION: The most common nosocomial pathogens may well survive or persist on surfaces for months and can thereby be a continuous source of transmission if no regular preventive surface disinfection is performed
The Population Structure of Acinetobacter baumannii: Expanding Multiresistant Clones from an Ancestral Susceptible Genetic Pool
Outbreaks of hospital infections caused by multidrug resistant Acinetobacter baumannii strains are of increasing concern worldwide. Although it has been reported that particular outbreak strains are geographically widespread, little is known about the diversity and phylogenetic relatedness of A. baumannii clonal groups. Sequencing of internal portions of seven housekeeping genes (total 2,976 nt) was performed in 154 A. baumannii strains covering the breadth of known diversity and including representatives of previously recognized international clones, and in 19 representatives of other Acinetobacter species. Restricted amounts of diversity and a star-like phylogeny reveal that A. baumannii is a genetically compact species that suffered a severe bottleneck in the recent past, possibly linked to a restricted ecological niche. A. baumannii is neatly demarcated from its closest relative (genomic species 13TU) and other Acinetobacter species. Multilocus sequence typing analysis demonstrated that the previously recognized international clones I to III correspond to three clonal complexes, each made of a central, predominant genotype and few single locus variants, a hallmark of recent clonal expansion. Whereas antimicrobial resistance was almost universal among isolates of these and a novel international clone (ST15), isolates of the other genotypes were mostly susceptible. This dichotomy indicates that antimicrobial resistance is a major selective advantage that drives the ongoing rapid clonal expansion of these highly problematic agents of nosocomial infections
Amelogenesis Imperfecta; Genes, Proteins And Pathways
Amelogenesis imperfecta (AI) is the name given to a heterogeneous group of conditions characterised by inherited developmental enamel defects. AI enamel is abnormally thin, soft, fragile, pitted and/or badly discoloured, with poor function and aesthetics, causing patients problems such as early tooth loss, severe embarrassment, eating difficulties and pain. It was first described separately from diseases of dentine nearly 80 years ago, but the underlying genetic and mechanistic basis of the condition is only now coming to light. Mutations in the gene AMELX, encoding an extracellular matrix protein secreted by ameloblasts during enamel formation, were first identified as a cause of AI in 1991. Since then, mutations in at least eighteen genes have been shown to cause AI presenting in isolation of other health problems, with many more implicated in syndromic AI. Some of the encoded proteins have well documented roles in amelogenesis, acting as enamel matrix proteins or the proteases that degrade them, cell adhesion molecules or regulators of calcium homeostasis. However, for others, function is less clear and further research is needed to understand the pathways and processes essential for the development of healthy enamel. Here, we review the genes and mutations underlying AI presenting in isolation of other health problems, the proteins they encode and knowledge of their roles in amelogenesis, combining evidence from human phenotypes, inheritance patterns, mouse models and in vitro studies. An LOVD resource (http://dna2.leeds.ac.uk/LOVD/) containing all published gene mutations for AI presenting in isolation of other health problems is described. We use this resource to identify trends in the genes and mutations reported to cause AI in the 270 families for which molecular diagnoses have been reported by 23rd May 2017. Finally we discuss the potential value of the translation of AI genetics to clinical care with improved patient pathways and speculate on the possibility of novel treatments and prevention strategies for AI
Relevance of laboratory testing for the diagnosis of primary immunodeficiencies: a review of case-based examples of selected immunodeficiencies
The field of primary immunodeficiencies (PIDs) is one of several in the area of clinical immunology that has not been static, but rather has shown exponential growth due to enhanced physician, scientist and patient education and awareness, leading to identification of new diseases, new molecular diagnoses of existing clinical phenotypes, broadening of the spectrum of clinical and phenotypic presentations associated with a single or related gene defects, increased bioinformatics resources, and utilization of advanced diagnostic technology and methodology for disease diagnosis and management resulting in improved outcomes and survival. There are currently over 200 PIDs with at least 170 associated genetic defects identified, with several of these being reported in recent years. The enormous clinical and immunological heterogeneity in the PIDs makes diagnosis challenging, but there is no doubt that early and accurate diagnosis facilitates prompt intervention leading to decreased morbidity and mortality. Diagnosis of PIDs often requires correlation of data obtained from clinical and radiological findings with laboratory immunological analyses and genetic testing. The field of laboratory diagnostic immunology is also rapidly burgeoning, both in terms of novel technologies and applications, and knowledge of human immunology. Over the years, the classification of PIDs has been primarily based on the immunological defect(s) ("immunophenotype") with the relatively recent addition of genotype, though there are clinical classifications as well. There can be substantial overlap in terms of the broad immunophenotype and clinical features between PIDs, and therefore, it is relevant to refine, at a cellular and molecular level, unique immunological defects that allow for a specific and accurate diagnosis. The diagnostic testing armamentarium for PID includes flow cytometry - phenotyping and functional, cellular and molecular assays, protein analysis, and mutation identification by gene sequencing. The complexity and diversity of the laboratory diagnosis of PIDs necessitates many of the above-mentioned tests being performed in highly specialized reference laboratories. Despite these restrictions, there remains an urgent need for improved standardization and optimization of phenotypic and functional flow cytometry and protein-specific assays. A key component in the interpretation of immunological assays is the comparison of patient data to that obtained in a statistically-robust manner from age and gender-matched healthy donors. This review highlights a few of the laboratory assays available for the diagnostic work-up of broad categories of PIDs, based on immunophenotyping, followed by examples of disease-specific testing
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