Kunioka, Masao
2010-06-01
The biomass carbon ratios of biochemicals related to biomass have been reviewed. Commercial products from biomass were explained. The biomass carbon ratios of biochemical compounds were measured by accelerator mass spectrometry (AMS) based on the (14)C concentration of carbons in the compounds. This measuring method uses the mechanism that biomass carbons include a very low level of (14)C and petroleum carbons do not include (14)C similar to the carbon dating measuring method. It was confirmed that there were some biochemicals synthesized from petroleum-based carbons. This AMS method has a high accuracy with a small standard deviation and can be applied to plastic products.
Nutritional assessment in intravenous drug users with HIV/AIDS.
Smit, E; Tang, A
2000-10-01
Studying metabolic, endocrine, and gastrointestinal (MEG) disorders in drug abuse and HIV infection is important. Equally important, however, are the tools we use to assess these disorders. Assessment of nutritional status may include any combination of biochemical and body composition measurements, dietary intake assessment, and metabolic studies. Each method has its strengths and weaknesses and there is no perfect tool. When assessing nutritional status in injection drug users (IDU) and in HIV-infected people, the decision on which method or methods to use becomes even more complex. A review of studies reported during the XII World Conference on AIDS reveals that of 64 abstracts on the topic of nutrition in HIV-infected adults, only 11 assessed diet, 41 assessed anthropometry, and 24 assessed some form of biochemical measure. The most commonly reported methods for dietary intake included 24-hour recalls, food records, and food frequencies. The commonest methods used for measuring body composition included height, weight, bioimpedance, and dual-energy x-ray absorptiometry (DEXA). Biochemical measurements included various blood nutrients, lipids, and albumin. Methods varied greatly between studies, and caution should be taken when trying to compare results across studies, especially among those using different methods. Currently, few studies deal with the development of methods that can be used for research in HIV-infected and IDU populations. We need to work toward better tools in dietary intake assessment, body composition, and biochemical measurements, especially methods that will allow us to track changes in nutritional status over time.
Kania, John; Qiao, Ming; Woods, Elizabeth M.; Cortright, Randy D.; Myren, Paul
2015-12-15
The present invention includes improved systems and methods for producing biomass-derived feedstocks for biofuel and biochemical manufacturing processes. The systems and methods use components that are capable of transferring relatively high concentrations of solid biomass utilizing pressure variations between vessels, and allows for the recovery and recycling of heterogeneous catalyst materials.
Phaeochromocytoma: diagnostic challenges for biochemical screening and diagnosis.
Barron, Jeffrey
2010-08-01
The aim of this article is to provide knowledge of the origin of catecholamines and metabolites so that there can be an informed approach to the methods for biochemical screening for a possible phaeochromocytoma; The article includes a review of catecholamine and metadrenaline metabolism, with methods used in biochemical screening. In the adrenal medulla and a phaeochromocytoma, catecholamines continuously leak from chromaffin granules into the cytoplasm and are converted to metadrenalines. For a phaeochromocytoma to become biochemically detectable, metnoradrenaline secretion needs to rise fourfold, whereas noradrenaline secretion needs to rise 15-fold. The prevalence of a sporadic phaeochromocytoma is low; therefore false-positive results exceed true-positive results. Assay sensitivity is high because it is important not to miss a possible phaeochromocytoma. The use of urine or plasma fractionated metadrenalines as the first-line test has been recommended due to improved sensitivity. A negative result excludes a phaeochromocytoma. Only after a sporadic phaeochromocytoma has been diagnosed biochemically is it cost effective to request imaging. Sensitivities and specificities of the assays differ according to pre-test probabilities of the presence of a phaeochromocytoma, with hereditary and incidentalomas having a higher pre-test probability than sporadic phaeochromocytoma. In conclusion, in screening for a possible phaeochromocytoma, biochemical investigations should be completed first to exclude or establish the diagnosis. The preferred biochemical screening test is fractionated metadrenalines, including methoxytyramine so as not to miss dopamine-secreting tumours.
Gurbuz, Nilgun; Aksu, Tevfik Aslan; Van Noorden, Cornelis J F
2005-01-01
The aim of this study was to diagnose heterozygous glucose-6-phosphate dehydrogenase (G6PD) deficient females by an inexpensive cytochemical G6PD staining method that is easy to perform, allowing diagnosis of G6PD deficiency without cumbersome genetic analysis. Three subject groups were included in the study. The first group consisted of 15 hemizygous deficient males. The second and the third group were composed of 15 heterozygous deficient females and 15 healthy individuals, respectively. Biochemical determination and cytochemical staining of G6PD activity were performed in samples of all subjects. Results obtained with the cytochemical staining method correlated significantly with the biochemical data (p < 0.001), but a only 51-68% of the erythrocytes were stained positively in females with normal biochemical G6PD activity despite their having a G6PD-deficient child. This observation clearly indicates that these individuals are heterozygously deficient. These findings show that the cytochemical staining method to detect G6PD activity in erythrocytes is reliable, sensitive and specific and is superior to the biochemical method. Therefore, this method can be used routinely to detect heterozygous G6PD deficiency.
Accessible methods for the dynamic time-scale decomposition of biochemical systems.
Surovtsova, Irina; Simus, Natalia; Lorenz, Thomas; König, Artjom; Sahle, Sven; Kummer, Ursula
2009-11-01
The growing complexity of biochemical models asks for means to rationally dissect the networks into meaningful and rather independent subnetworks. Such foregoing should ensure an understanding of the system without any heuristics employed. Important for the success of such an approach is its accessibility and the clarity of the presentation of the results. In order to achieve this goal, we developed a method which is a modification of the classical approach of time-scale separation. This modified method as well as the more classical approach have been implemented for time-dependent application within the widely used software COPASI. The implementation includes different possibilities for the representation of the results including 3D-visualization. The methods are included in COPASI which is free for academic use and available at www.copasi.org. irina.surovtsova@bioquant.uni-heidelberg.de Supplementary data are available at Bioinformatics online.
McKnight, Timothy E; Melechko, Anatoli V; Griffin, Guy D; Guillorn, Michael A; Merkulov, Vladimir L; Simpson, Michael L
2015-03-31
Systems and methods are described for parallel macromolecular delivery and biochemical/electrochemical interface to whole cells employing carbon nanostructures including nanofibers and nanotubes. A method includes providing a first material on at least a first portion of a first surface of a first tip of a first elongated carbon nanostructure; providing a second material on at least a second portion of a second surface of a second tip of a second elongated carbon nanostructure, the second elongated carbon nanostructure coupled to, and substantially parallel to, the first elongated carbon nanostructure; and penetrating a boundary of a biological sample with at least one member selected from the group consisting of the first tip and the second tip.
Exercise-induced biochemical changes and their potential influence on cancer: a scientific review
Thomas, Robert James; Kenfield, Stacey A; Jimenez, Alfonso
2017-01-01
Aim To review and discuss the available international literature regarding the indirect and direct biochemical mechanisms that occur after exercise, which could positively, or negatively, influence oncogenic pathways. Methods The PubMed, MEDLINE, Embase and Cochrane libraries were searched for papers up to July 2016 addressing biochemical changes after exercise with a particular reference to cancer. The three authors independently assessed their appropriateness for inclusion in this review based on their scientific quality and relevance. Results 168 papers were selected and categorised into indirect and direct biochemical pathways. The indirect effects included changes in vitamin D, weight reduction, sunlight exposure and improved mood. The direct effects included insulin-like growth factor, epigenetic effects on gene expression and DNA repair, vasoactive intestinal peptide, oxidative stress and antioxidant pathways, heat shock proteins, testosterone, irisin, immunity, chronic inflammation and prostaglandins, energy metabolism and insulin resistance. Summary Exercise is one of several lifestyle factors known to lower the risk of developing cancer and is associated with lower relapse rates and better survival. This review highlights the numerous biochemical processes, which explain these potential anticancer benefits. PMID:27993842
Meng, X Flora; Baetica, Ania-Ariadna; Singhal, Vipul; Murray, Richard M
2017-05-01
Noise is often indispensable to key cellular activities, such as gene expression, necessitating the use of stochastic models to capture its dynamics. The chemical master equation (CME) is a commonly used stochastic model of Kolmogorov forward equations that describe how the probability distribution of a chemically reacting system varies with time. Finding analytic solutions to the CME can have benefits, such as expediting simulations of multiscale biochemical reaction networks and aiding the design of distributional responses. However, analytic solutions are rarely known. A recent method of computing analytic stationary solutions relies on gluing simple state spaces together recursively at one or two states. We explore the capabilities of this method and introduce algorithms to derive analytic stationary solutions to the CME. We first formally characterize state spaces that can be constructed by performing single-state gluing of paths, cycles or both sequentially. We then study stochastic biochemical reaction networks that consist of reversible, elementary reactions with two-dimensional state spaces. We also discuss extending the method to infinite state spaces and designing the stationary behaviour of stochastic biochemical reaction networks. Finally, we illustrate the aforementioned ideas using examples that include two interconnected transcriptional components and biochemical reactions with two-dimensional state spaces. © 2017 The Author(s).
Baetica, Ania-Ariadna; Singhal, Vipul; Murray, Richard M.
2017-01-01
Noise is often indispensable to key cellular activities, such as gene expression, necessitating the use of stochastic models to capture its dynamics. The chemical master equation (CME) is a commonly used stochastic model of Kolmogorov forward equations that describe how the probability distribution of a chemically reacting system varies with time. Finding analytic solutions to the CME can have benefits, such as expediting simulations of multiscale biochemical reaction networks and aiding the design of distributional responses. However, analytic solutions are rarely known. A recent method of computing analytic stationary solutions relies on gluing simple state spaces together recursively at one or two states. We explore the capabilities of this method and introduce algorithms to derive analytic stationary solutions to the CME. We first formally characterize state spaces that can be constructed by performing single-state gluing of paths, cycles or both sequentially. We then study stochastic biochemical reaction networks that consist of reversible, elementary reactions with two-dimensional state spaces. We also discuss extending the method to infinite state spaces and designing the stationary behaviour of stochastic biochemical reaction networks. Finally, we illustrate the aforementioned ideas using examples that include two interconnected transcriptional components and biochemical reactions with two-dimensional state spaces. PMID:28566513
Efficient simulation of intrinsic, extrinsic and external noise in biochemical systems
Pischel, Dennis; Sundmacher, Kai; Flassig, Robert J.
2017-01-01
Abstract Motivation: Biological cells operate in a noisy regime influenced by intrinsic, extrinsic and external noise, which leads to large differences of individual cell states. Stochastic effects must be taken into account to characterize biochemical kinetics accurately. Since the exact solution of the chemical master equation, which governs the underlying stochastic process, cannot be derived for most biochemical systems, approximate methods are used to obtain a solution. Results: In this study, a method to efficiently simulate the various sources of noise simultaneously is proposed and benchmarked on several examples. The method relies on the combination of the sigma point approach to describe extrinsic and external variability and the τ-leaping algorithm to account for the stochasticity due to probabilistic reactions. The comparison of our method to extensive Monte Carlo calculations demonstrates an immense computational advantage while losing an acceptable amount of accuracy. Additionally, the application to parameter optimization problems in stochastic biochemical reaction networks is shown, which is rarely applied due to its huge computational burden. To give further insight, a MATLAB script is provided including the proposed method applied to a simple toy example of gene expression. Availability and implementation: MATLAB code is available at Bioinformatics online. Contact: flassig@mpi-magdeburg.mpg.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28881987
He, Qili; Su, Guoming; Liu, Keliang; Zhang, Fangcheng; Jiang, Yong; Gao, Jun; Liu, Lida; Jiang, Zhongren; Jin, Minwu; Xie, Huiping
2017-01-01
Hematologic and biochemical analytes of Sprague-Dawley rats are commonly used to determine effects that were induced by treatment and to evaluate organ dysfunction in toxicological safety assessments, but reference intervals have not been well established for these analytes. Reference intervals as presently defined for these analytes in Sprague-Dawley rats have not used internationally recommended statistical method nor stratified by sex. Thus, we aimed to establish sex-specific reference intervals for hematologic and biochemical parameters in Sprague-Dawley rats according to Clinical and Laboratory Standards Institute C28-A3 and American Society for Veterinary Clinical Pathology guideline. Hematology and biochemistry blood samples were collected from 500 healthy Sprague-Dawley rats (250 males and 250 females) in the control groups. We measured 24 hematologic analytes with the Sysmex XT-2100i analyzer, 9 biochemical analytes with the Olympus AU400 analyzer. We then determined statistically relevant sex partitions and calculated reference intervals, including corresponding 90% confidence intervals, using nonparametric rank percentile method. We observed that most hematologic and biochemical analytes of Sprague-Dawley rats were significantly influenced by sex. Males had higher hemoglobin, hematocrit, red blood cell count, red cell distribution width, mean corpuscular volume, mean corpuscular hemoglobin, white blood cell count, neutrophils, lymphocytes, monocytes, percentage of neutrophils, percentage of monocytes, alanine aminotransferase, aspartate aminotransferase, and triglycerides compared to females. Females had higher mean corpuscular hemoglobin concentration, plateletcrit, platelet count, eosinophils, percentage of lymphocytes, percentage of eosinophils, creatinine, glucose, total cholesterol and urea compared to males. Sex partition was required for most hematologic and biochemical analytes in Sprague-Dawley rats. We established sex-specific reference intervals, including corresponding 90% confidence intervals, for Sprague-Dawley rats. Understanding the significant discrepancies in hematologic and biochemical analytes between male and female Sprague-Dawley rats provides important insight into physiological effects in test rats. Establishment of locally sex-specific reference intervals allows a more precise evaluation of animal quality and experimental results of Sprague-Dawley rats in our toxicology safety assessment.
Efficient simulation of intrinsic, extrinsic and external noise in biochemical systems.
Pischel, Dennis; Sundmacher, Kai; Flassig, Robert J
2017-07-15
Biological cells operate in a noisy regime influenced by intrinsic, extrinsic and external noise, which leads to large differences of individual cell states. Stochastic effects must be taken into account to characterize biochemical kinetics accurately. Since the exact solution of the chemical master equation, which governs the underlying stochastic process, cannot be derived for most biochemical systems, approximate methods are used to obtain a solution. In this study, a method to efficiently simulate the various sources of noise simultaneously is proposed and benchmarked on several examples. The method relies on the combination of the sigma point approach to describe extrinsic and external variability and the τ -leaping algorithm to account for the stochasticity due to probabilistic reactions. The comparison of our method to extensive Monte Carlo calculations demonstrates an immense computational advantage while losing an acceptable amount of accuracy. Additionally, the application to parameter optimization problems in stochastic biochemical reaction networks is shown, which is rarely applied due to its huge computational burden. To give further insight, a MATLAB script is provided including the proposed method applied to a simple toy example of gene expression. MATLAB code is available at Bioinformatics online. flassig@mpi-magdeburg.mpg.de. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com
Leonard, Annemarie K; Loughran, Elizabeth A; Klymenko, Yuliya; Liu, Yueying; Kim, Oleg; Asem, Marwa; McAbee, Kevin; Ravosa, Matthew J; Stack, M Sharon
2018-01-01
This chapter highlights methods for visualization and analysis of extracellular matrix (ECM) proteins, with particular emphasis on collagen type I, the most abundant protein in mammals. Protocols described range from advanced imaging of complex in vivo matrices to simple biochemical analysis of individual ECM proteins. The first section of this chapter describes common methods to image ECM components and includes protocols for second harmonic generation, scanning electron microscopy, and several histological methods of ECM localization and degradation analysis, including immunohistochemistry, Trichrome staining, and in situ zymography. The second section of this chapter details both a common transwell invasion assay and a novel live imaging method to investigate cellular behavior with respect to collagen and other ECM proteins of interest. The final section consists of common electrophoresis-based biochemical methods that are used in analysis of ECM proteins. Use of the methods described herein will enable researchers to gain a greater understanding of the role of ECM structure and degradation in development and matrix-related diseases such as cancer and connective tissue disorders. © 2018 Elsevier Inc. All rights reserved.
Prokofieva, D S; Shmurak, V I; Sadovnikov, S V; Gontcharov, N V
2015-01-01
The article covers problems of biochemical methods assessing organophosphorus toxic compounds in objects of chemical weapons extinction. The authors present results of works developing new, more specific and selective biochemical methods.
NASA Astrophysics Data System (ADS)
Lappa, Alexander V.; Kulikovskiy, Artem N.; Busarov, Oleg G.
2014-03-01
The paper presents a new method for distant non-destructive determination of concentration of light absorbing admixtures in turbid media. In particular, it is intended for non-invasive in vivo control of accumulation in patient tissues of various biochemicals introduced to the patients for chemotherapy, photodynamic therapy or diagnostics. It is require that the admixture absorption spectrum should have a clearly marked peak in the wavelength region where the pure medium one varies regularly. Fluorescence of admixtures is not required. The method uses the local diffuse reflectance spectroscopy with optical fiber probe including one emitting and two reading There are several features in the method: the value to be determined is absolute concentration of admixtures; the method needs no calibration measurements on phantoms; it needs no reference measurements on sample with zero admixture concentration; it uses a two parametric kinetic light propagation model and original algorithms to resolve direct and inverse tasks of radiation transport theory. Experimental testing passed with tissue equivalent phantoms and different admixtures, including a chlorine photosensitizer, showed accuracy under 10% in all cases.
Inoue, Kentaro; Maeda, Kazuhiro; Miyabe, Takaaki; Matsuoka, Yu; Kurata, Hiroyuki
2014-09-01
Mathematical modeling has become a standard technique to understand the dynamics of complex biochemical systems. To promote the modeling, we had developed the CADLIVE dynamic simulator that automatically converted a biochemical map into its associated mathematical model, simulated its dynamic behaviors and analyzed its robustness. To enhance the feasibility by CADLIVE and extend its functions, we propose the CADLIVE toolbox available for MATLAB, which implements not only the existing functions of the CADLIVE dynamic simulator, but also the latest tools including global parameter search methods with robustness analysis. The seamless, bottom-up processes consisting of biochemical network construction, automatic construction of its dynamic model, simulation, optimization, and S-system analysis greatly facilitate dynamic modeling, contributing to the research of systems biology and synthetic biology. This application can be freely downloaded from http://www.cadlive.jp/CADLIVE_MATLAB/ together with an instruction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riaz, Nadeem; Afaq, Asim; Akin, Oguz
Purpose: To investigate the utility of endorectal coil magenetic resonance imaging (eMRI) in predicting biochemical relapse in prostate cancer patients treated with combination brachytherapy and external-beam radiotherapy. Methods and Materials: Between 2000 and 2008, 279 men with intermediate- or high-risk prostate cancer underwent eMRI of their prostate before receiving brachytherapy and supplemental intensity-modulated radiotherapy. Endorectal coil MRI was performed before treatment and retrospectively reviewed by two radiologists experienced in genitourinary MRI. Image-based variables, including tumor diameter, location, number of sextants involved, and the presence of extracapsular extension (ECE), were incorporated with other established clinical variables to predict biochemical control outcomes.more » The median follow-up was 49 months (range, 1-13 years). Results: The 5-year biochemical relapse-free survival for the cohort was 92%. Clinical findings predicting recurrence on univariate analysis included Gleason score (hazard ratio [HR] 3.6, p = 0.001), PSA (HR 1.04, p = 0.005), and National Comprehensive Cancer Network risk group (HR 4.1, p = 0.002). Clinical T stage and the use of androgen deprivation therapy were not correlated with biochemical failure. Imaging findings on univariate analysis associated with relapse included ECE on MRI (HR 3.79, p = 0.003), tumor size (HR 2.58, p = 0.04), and T stage (HR 1.71, p = 0.004). On multivariate analysis incorporating both clinical and imaging findings, only ECE on MRI and Gleason score were independent predictors of recurrence. Conclusions: Pretreatment eMRI findings predict for biochemical recurrence in intermediate- and high-risk prostate cancer patients treated with combination brachytherapy and external-beam radiotherapy. Gleason score and the presence of ECE on MRI were the only significant predictors of biochemical relapse in this group of patients.« less
Methods for pretreating biomass
Balan, Venkatesh; Dale, Bruce E; Chundawat, Shishir; Sousa, Leonardo
2017-05-09
A method for pretreating biomass is provided, which includes, in a reactor, allowing gaseous ammonia to condense on the biomass and react with water present in the biomass to produce pretreated biomass, wherein reactivity of polysaccharides in the biomass is increased during subsequent biological conversion as compared to the reactivity of polysaccharides in biomass which has not been pretreated. A method for pretreating biomass with a liquid ammonia and recovering the liquid ammonia is also provided. Related systems which include a biochemical or biofuel production facility are also disclosed.
Modelling biochemical reaction systems by stochastic differential equations with reflection.
Niu, Yuanling; Burrage, Kevin; Chen, Luonan
2016-05-07
In this paper, we gave a new framework for modelling and simulating biochemical reaction systems by stochastic differential equations with reflection not in a heuristic way but in a mathematical way. The model is computationally efficient compared with the discrete-state Markov chain approach, and it ensures that both analytic and numerical solutions remain in a biologically plausible region. Specifically, our model mathematically ensures that species numbers lie in the domain D, which is a physical constraint for biochemical reactions, in contrast to the previous models. The domain D is actually obtained according to the structure of the corresponding chemical Langevin equations, i.e., the boundary is inherent in the biochemical reaction system. A variant of projection method was employed to solve the reflected stochastic differential equation model, and it includes three simple steps, i.e., Euler-Maruyama method was applied to the equations first, and then check whether or not the point lies within the domain D, and if not perform an orthogonal projection. It is found that the projection onto the closure D¯ is the solution to a convex quadratic programming problem. Thus, existing methods for the convex quadratic programming problem can be employed for the orthogonal projection map. Numerical tests on several important problems in biological systems confirmed the efficiency and accuracy of this approach. Copyright © 2016 Elsevier Ltd. All rights reserved.
Methods for Discovery of Novel Cellulosomal Cellulases Using Genomics and Biochemical Tools.
Ben-David, Yonit; Dassa, Bareket; Bensoussan, Lizi; Bayer, Edward A; Moraïs, Sarah
2018-01-01
Cell wall degradation by cellulases is extensively explored owing to its potential contribution to biofuel production. The cellulosome is an extracellular multienzyme complex that can degrade the plant cell wall very efficiently, and cellulosomal enzymes are therefore of great interest. The cellulosomal cellulases are defined as enzymes that contain a dockerin module, which can interact with a cohesin module contained in multiple copies in a noncatalytic protein, termed scaffoldin. The assembly of the cellulosomal cellulases into the cellulosomal complex occurs via specific protein-protein interactions. Cellulosome systems have been described initially only in several anaerobic cellulolytic bacteria. However, owing to ongoing genome sequencing and metagenomic projects, the discovery of novel cellulosome-producing bacteria and the description of their cellulosomal genes have dramatically increased in the recent years. In this chapter, methods for discovery of novel cellulosomal cellulases from a DNA sequence by bioinformatics and biochemical tools are described. Their biochemical characterization is also described, including both the enzymatic activity of the putative cellulases and their assembly into mature designer cellulosomes.
Snowden, Thomas J; van der Graaf, Piet H; Tindall, Marcus J
2017-07-01
Complex models of biochemical reaction systems have become increasingly common in the systems biology literature. The complexity of such models can present a number of obstacles for their practical use, often making problems difficult to intuit or computationally intractable. Methods of model reduction can be employed to alleviate the issue of complexity by seeking to eliminate those portions of a reaction network that have little or no effect upon the outcomes of interest, hence yielding simplified systems that retain an accurate predictive capacity. This review paper seeks to provide a brief overview of a range of such methods and their application in the context of biochemical reaction network models. To achieve this, we provide a brief mathematical account of the main methods including timescale exploitation approaches, reduction via sensitivity analysis, optimisation methods, lumping, and singular value decomposition-based approaches. Methods are reviewed in the context of large-scale systems biology type models, and future areas of research are briefly discussed.
Chanchaithong, Pattrarat; Prapasarakul, Nuvee
2011-08-01
Coagulase-positive staphylococci (CoPS) including S. pseudintermedius, S. schleiferi subsp. coagulans and S. aureus are etiological agents of dermatitis in companion animals and can be zoonotic pathogens. To date no consensual biochemical marker for routine microbiological identification of these species has been identified. The aim of this study was to evaluate biochemical markers and compare the results with the approved molecular method, multiplex-PCR (M-PCR), and confirm their species-specific phenotypic characteristic by using SDS-PAGE. The distribution and frequency of CoPS species were also determined. Three hundred and thirty-seven canine CoPS isolates were obtained from the nasal mucosa, perineum and groins of 66 healthy dogs and were identified by the M-PCR as S. aureus (n=5), S. pseudintermedius (n=263) and S. schleiferi subsp. coagulans (n=69). Selected biochemical tests including the Voges-Proskauer test, mannitol broth fermentation, the assimilation of maltose, galactose, trahalose and lactose using broth medium, were successfully used to distinguish the three species of canine CoPS from other CoPS species. Additionally, species-specific protein patterns were also found to be useful for phenotypic differentiation, with good agreement with the results of M-PCR and the use of biochemical markers. S. aureus occured infrequently on dog skin while co-colonization with S. pseudintermedius and S. schleiferi subsp. coagulans was observed. We propose the use of consensual biochemical markers of canine CoPS with the presence of the unique protein patterns as an alternative tool for conventional laboratory use. Copyright © 2011 Elsevier B.V. All rights reserved.
He, Yuhong; Mui, Amy
2010-01-01
Remote sensing imagery is being used intensively to estimate the biochemical content of vegetation (e.g., chlorophyll, nitrogen, and lignin) at the leaf level. As a result of our need for vegetation biochemical information and our increasing ability to obtain canopy spectral data, a few techniques have been explored to scale leaf-level biochemical content to the canopy level for forests and crops. However, due to the contribution of non-green materials (i.e., standing dead litter, rock, and bare soil) from canopy spectra in semi-arid grasslands, it is difficult to obtain information about grassland biochemical content from remote sensing data at the canopy level. This paper summarizes available methods used to scale biochemical information from the leaf level to the canopy level and groups these methods into three categories: direct extrapolation, canopy-integrated approach, and inversion of physical models. As for semi-arid heterogeneous grasslands, we conclude that all methods are useful, but none are ideal. It is recommended that future research should explore a systematic upscaling framework which combines spatial pattern analysis, canopy-integrated approach, and modeling methods to retrieve vegetation biochemical content at the canopy level.
Novel Contrast Mechanisms at 3 Tesla and 7 Tesla
Regatte, Ravinder R.; Schweitzer, Mark E.
2013-01-01
Osteoarthritis (OA) is the most common musculoskeletal degenerative disease, affecting millions of people. Although OA has been considered primarily a cartilage disorder associated with focal cartilage degeneration, it is accompanied by well-known changes in subchondral and trabecular bone, including sclerosis and osteophyte formation. The exact cause of OA initiation and progression remains under debate, but OA typically first affects weightbearing joints such as the knee. Magnetic resonance imaging (MRI) has been recognized as a potential tool for quantitative assessment of cartilage abnormalities due to its excellent soft tissue contrast. Over the last two decades, several new MR biochemical imaging methods have been developed to characterize the disease process and possibly predict the progression of knee OA. These new MR biochemical methods play an important role not only for diagnosis of disease at an early stage, but also for their potential use in monitoring outcome of various drug therapies (success or failure). Recent advances in multicoil radiofrequency technology and high field systems (3 T and above) significantly improve the sensitivity and specificity of imaging studies for the diagnosis of musculoskeletal disorders. The current state-of-the-art MR imaging methods are briefly reviewed for the quantitative biochemical and functional imaging assessment of musculoskeletal systems. PMID:18850506
A Geometric Method for Model Reduction of Biochemical Networks with Polynomial Rate Functions.
Samal, Satya Swarup; Grigoriev, Dima; Fröhlich, Holger; Weber, Andreas; Radulescu, Ovidiu
2015-12-01
Model reduction of biochemical networks relies on the knowledge of slow and fast variables. We provide a geometric method, based on the Newton polytope, to identify slow variables of a biochemical network with polynomial rate functions. The gist of the method is the notion of tropical equilibration that provides approximate descriptions of slow invariant manifolds. Compared to extant numerical algorithms such as the intrinsic low-dimensional manifold method, our approach is symbolic and utilizes orders of magnitude instead of precise values of the model parameters. Application of this method to a large collection of biochemical network models supports the idea that the number of dynamical variables in minimal models of cell physiology can be small, in spite of the large number of molecular regulatory actors.
Evaluation of Polymerase Chain Reaction for Detecting Coliform Bacteria in Drinking Water Sources.
Isfahani, Bahram Nasr; Fazeli, Hossein; Babaie, Zeinab; Poursina, Farkhondeh; Moghim, Sharareh; Rouzbahani, Meisam
2017-01-01
Coliform bacteria are used as indicator organisms for detecting fecal pollution in water. Traditional methods including microbial culture tests in lactose-containing media and enzyme-based tests for the detection of β-galactosidase; however, these methods are time-consuming and less specific. The aim of this study was to evaluate polymerase chain reaction (PCR) for detecting coliform. Totally, 100 of water samples from Isfahan drinking water source were collected. Coliform bacteria and Escherichia coli were detected in drinking water using LacZ and LamB genes in PCR method performed in comparison with biochemical tests for all samples. Using phenotyping, 80 coliform isolates were found. The results of the biochemical tests illustrated 78.7% coliform bacteria and 21.2% E. coli . PCR results for LacZ and LamB genes were 67.5% and 17.5%, respectively. The PCR method was shown to be an effective, sensitive, and rapid method for detecting coliform and E. coli in drinking water from the Isfahan drinking water sources.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Kaiguang; Valle, Denis; Popescu, Sorin
2013-05-15
Model specification remains challenging in spectroscopy of plant biochemistry, as exemplified by the availability of various spectral indices or band combinations for estimating the same biochemical. This lack of consensus in model choice across applications argues for a paradigm shift in hyperspectral methods to address model uncertainty and misspecification. We demonstrated one such method using Bayesian model averaging (BMA), which performs variable/band selection and quantifies the relative merits of many candidate models to synthesize a weighted average model with improved predictive performances. The utility of BMA was examined using a portfolio of 27 foliage spectral–chemical datasets representing over 80 speciesmore » across the globe to estimate multiple biochemical properties, including nitrogen, hydrogen, carbon, cellulose, lignin, chlorophyll (a or b), carotenoid, polar and nonpolar extractives, leaf mass per area, and equivalent water thickness. We also compared BMA with partial least squares (PLS) and stepwise multiple regression (SMR). Results showed that all the biochemicals except carotenoid were accurately estimated from hyerspectral data with R2 values > 0.80.« less
Santos, André S; Ramos, Rommel T; Silva, Artur; Hirata, Raphael; Mattos-Guaraldi, Ana L; Meyer, Roberto; Azevedo, Vasco; Felicori, Liza; Pacheco, Luis G C
2018-05-11
Biochemical tests are traditionally used for bacterial identification at the species level in clinical microbiology laboratories. While biochemical profiles are generally efficient for the identification of the most important corynebacterial pathogen Corynebacterium diphtheriae, their ability to differentiate between biovars of this bacterium is still controversial. Besides, the unambiguous identification of emerging human pathogenic species of the genus Corynebacterium may be hampered by highly variable biochemical profiles commonly reported for these species, including Corynebacterium striatum, Corynebacterium amycolatum, Corynebacterium minutissimum, and Corynebacterium xerosis. In order to identify the genomic basis contributing for the biochemical variabilities observed in phenotypic identification methods of these bacteria, we combined a comprehensive literature review with a bioinformatics approach based on reconstruction of six specific biochemical reactions/pathways in 33 recently released whole genome sequences. We used data retrieved from curated databases (MetaCyc, PathoSystems Resource Integration Center (PATRIC), The SEED, TransportDB, UniProtKB) associated with homology searches by BLAST and profile Hidden Markov Models (HMMs) to detect enzymes participating in the various pathways and performed ab initio protein structure modeling and molecular docking to confirm specific results. We found a differential distribution among the various strains of genes that code for some important enzymes, such as beta-phosphoglucomutase and fructokinase, and also for individual components of carbohydrate transport systems, including the fructose-specific phosphoenolpyruvate-dependent sugar phosphotransferase (PTS) and the ribose-specific ATP-binging cassette (ABC) transporter. Horizontal gene transfer plays a role in the biochemical variability of the isolates, as some genes needed for sucrose fermentation were seen to be present in genomic islands. Noteworthy, using profile HMMs, we identified an enzyme with putative alpha-1,6-glycosidase activity only in some specific strains of C. diphtheriae and this may aid to understanding of the differential abilities to utilize glycogen and starch between the biovars.
Three-dimensional label-free imaging and quantification of lipid droplets in live hepatocytes
NASA Astrophysics Data System (ADS)
Kim, Kyoohyun; Lee, Seoeun; Yoon, Jonghee; Heo, Jihan; Choi, Chulhee; Park, Yongkeun
2016-11-01
Lipid droplets (LDs) are subcellular organelles with important roles in lipid storage and metabolism and involved in various diseases including cancer, obesity, and diabetes. Conventional methods, however, have limited ability to provide quantitative information on individual LDs and have limited capability for three-dimensional (3-D) imaging of LDs in live cells especially for fast acquisition of 3-D dynamics. Here, we present an optical method based on 3-D quantitative phase imaging to measure the 3-D structural distribution and biochemical parameters (concentration and dry mass) of individual LDs in live cells without using exogenous labelling agents. The biochemical change of LDs under oleic acid treatment was quantitatively investigated, and 4-D tracking of the fast dynamics of LDs revealed the intracellular transport of LDs in live cells.
Flow Injection Technique for Biochemical Analysis with Chemiluminescence Detection in Acidic Media
Chen, Jing; Fang, Yanjun
2007-01-01
A review with 90 references is presented to show the development of acidic chemiluminescence methods for biochemical analysis by use of flow injection technique in the last 10 years. A brief discussion of both the chemiluminescence and flow injection technique is given. The proposed methods for biochemical analysis are described and compared according to the used chemiluminescence system.
Why minimally invasive skin sampling techniques? A bright scientific future.
Wang, Christina Y; Maibach, Howard I
2011-03-01
There is increasing interest in minimally invasive skin sampling techniques to assay markers of molecular biology and biochemical processes. This overview examines methodology strengths and limitations, and exciting developments pending in the scientific community. Publications were searched via PubMed, the U.S. Patent and Trademark Office Website, the DermTech Website and the CuDerm Website. The keywords used were noninvasive skin sampling, skin stripping, skin taping, detergent method, ring method, mechanical scrub, reverse iontophoresis, glucose monitoring, buccal smear, hair root sampling, mRNA, DNA, RNA, and amino acid. There is strong interest in finding methods to access internal biochemical, molecular, and genetic processes through noninvasive and minimally invasive external means. Minimally invasive techniques include the widely used skin tape stripping, the abrasion method that includes scraping and detergent, and reverse iontophoresis. The first 2 methods harvest largely the stratum corneum. Hair root sampling (material deeper than the epidermis), buccal smear, shave biopsy, punch biopsy, and suction blistering are also methods used to obtain cellular material for analysis, but involve some degree of increased invasiveness and thus are only briefly mentioned. Existing and new sampling methods are being refined and validated, offering exciting, different noninvasive means of quickly and efficiently obtaining molecular material with which to monitor bodily functions and responses, assess drug levels, and follow disease processes without subjecting patients to unnecessary discomfort and risk.
Evaluation of Polymerase Chain Reaction for Detecting Coliform Bacteria in Drinking Water Sources
Isfahani, Bahram Nasr; Fazeli, Hossein; Babaie, Zeinab; Poursina, Farkhondeh; Moghim, Sharareh; Rouzbahani, Meisam
2017-01-01
Background: Coliform bacteria are used as indicator organisms for detecting fecal pollution in water. Traditional methods including microbial culture tests in lactose-containing media and enzyme-based tests for the detection of β-galactosidase; however, these methods are time-consuming and less specific. The aim of this study was to evaluate polymerase chain reaction (PCR) for detecting coliform. Materials and Methods: Totally, 100 of water samples from Isfahan drinking water source were collected. Coliform bacteria and Escherichia coli were detected in drinking water using LacZ and LamB genes in PCR method performed in comparison with biochemical tests for all samples. Results: Using phenotyping, 80 coliform isolates were found. The results of the biochemical tests illustrated 78.7% coliform bacteria and 21.2% E. coli. PCR results for LacZ and LamB genes were 67.5% and 17.5%, respectively. Conclusion: The PCR method was shown to be an effective, sensitive, and rapid method for detecting coliform and E. coli in drinking water from the Isfahan drinking water sources. PMID:29142893
Petersen, Lars J.; Nielsen, Julie B.; Dettmann, Katja; Fisker, Rune V.; Haberkorn, Uwe; Stenholt, Louise; Zacho, Helle D.
2017-01-01
Localization of prostate cancer recurrence, particularly in the bones, is a major challenge with standard of care imaging in patients with biochemical recurrence following curatively intended treatment. Gallium-68-labeled prostate specific membrane antigen positron emission tomography/computed tomography (68Ga-PSMA PET/CT) is a novel and promising method for imaging in prostate cancer. The present study reports two cases of patients with prostate cancer with biochemical recurrence, with evidence of bone metastases on 68Ga-PSMA PET/CT images and low prostate specific antigen PSA levels (<2 ng/ml) and PSA doubling time >6 months. The bone metastases were verified by supplementary imaging with 18F-sodium fluoride PET/CT and magnetic resonance imaging as well as biochemical responses to androgen deprivation therapy. Therefore, 68Ga-PSMA PET/CT is promising for the restaging of patients with prostate cancer with biochemical recurrence, including patients with low PSA levels and low PSA kinetics. PMID:28685078
Exact lower and upper bounds on stationary moments in stochastic biochemical systems
NASA Astrophysics Data System (ADS)
Ghusinga, Khem Raj; Vargas-Garcia, Cesar A.; Lamperski, Andrew; Singh, Abhyudai
2017-08-01
In the stochastic description of biochemical reaction systems, the time evolution of statistical moments for species population counts is described by a linear dynamical system. However, except for some ideal cases (such as zero- and first-order reaction kinetics), the moment dynamics is underdetermined as lower-order moments depend upon higher-order moments. Here, we propose a novel method to find exact lower and upper bounds on stationary moments for a given arbitrary system of biochemical reactions. The method exploits the fact that statistical moments of any positive-valued random variable must satisfy some constraints that are compactly represented through the positive semidefiniteness of moment matrices. Our analysis shows that solving moment equations at steady state in conjunction with constraints on moment matrices provides exact lower and upper bounds on the moments. These results are illustrated by three different examples—the commonly used logistic growth model, stochastic gene expression with auto-regulation and an activator-repressor gene network motif. Interestingly, in all cases the accuracy of the bounds is shown to improve as moment equations are expanded to include higher-order moments. Our results provide avenues for development of approximation methods that provide explicit bounds on moments for nonlinear stochastic systems that are otherwise analytically intractable.
Xu, Lijuan; Liu, Zijian; Li, Yang; Yin, Chao; Hu, Yachen; Xie, Xiaolei; Li, Qiuchun; Jiao, Xinan
2018-06-01
Salmonella enterica serovar Gallinarum biovar Pullorum (S. Pullorum) is the pathogen of pullorum disease, which leads to severe economic losses in many developing countries. Traditional methods to identify S. enterica have relied on biochemical reactions and serotyping, which are time-consuming with accurate identification if properly carried out. In this study, we developed a rapid polymerase chain reaction (PCR) method targeting the specific gene ipaJ to detect S. Pullorum. Among the 650 S. Pullorum strains isolated from 1962 to 2016 all over China, 644 strains were identified to harbour ipaJ gene in the plasmid pSPI12, accounting for a detection rate of 99.08%. Six strains were ipaJ negative because pSPI12 was not found in these strains according to whole genome sequencing results. There was no cross-reaction with other Salmonella serotypes, including Salmonella enterica serovar Gallinarum biovar Gallinarum (S. Gallinarum), which show a close genetic relationship with S. Pullorum. This shows that the PCR method could distinguish S. Gallinarum from S. Pullorum in one-step PCR without complicated biochemical identification. The limit of detection of this PCR method was as low as 90 fg/μl or 10 2 CFU, which shows a high sensitivity. Moreover, this method was applied to identify Salmonella isolated from the chicken farm and the results were consistent with what we obtained from biochemical reactions and serotyping. Together, all the results demonstrated that this one-step PCR method is simple and feasible to efficiently identify S. Pullorum.
Narita, Shintaro; Mitsuzuka, Koji; Tsuchiya, Norihiko; Koie, Takuya; Kawamura, Sadafumi; Ohyama, Chikara; Tochigi, Tatsuo; Yamaguchi, Takuhiro; Arai, Yoichi; Habuchi, Tomonori
2015-11-01
To assess the risk factors for biochemical recurrence in D'Amico intermediate-risk prostate cancer patients treated using radical prostatectomy. We retrospectively reviewed the medical records of 1268 men with prostate cancer treated using radical prostatectomy without neoadjuvant therapy. The association between various risk factors and biochemical recurrence was then statistically evaluated. The Kaplan-Meier method, log-rank tests and Cox proportional hazards models were used for statistical analysis. In the intermediate-risk group, 96 patients (14.5%) experienced biochemical recurrence during a median follow up of 41 months. In the intermediate-risk group, preoperative prostate-specific antigen level, prostate volume and prostate-specific antigen density were significant preoperative risk factors for biochemical recurrence, whereas other factors including age, primary Gleason 4, clinical stage >T2 and percentage of positive biopsies were not. In multivariate analysis, higher preoperative prostate-specific antigen level and density, and a smaller prostate volume were independent risk factors for biochemical recurrence in the intermediate-risk group. Biochemical recurrence-free survival of patients in the intermediate-risk group with a higher prostate-specific antigen level and density (≥15 ng/mL, ≥0.6 ng/mL/cm(3), respectively), and lower prostate volume (≤10 mL) was comparable with that of high-risk group individuals (P = 0.632, 0.494 and 0.961, respectively). Preoperative prostate-specific antigen, prostate volume and prostate-specific antigen density are significant risk factors for biochemical recurrence in D'Amico intermediate-risk prostate cancer patients treated using radical prostatectomy. Using these variables, a subset of the intermediate-risk patients can be identified as having equivalent outcomes to high-risk patients. © 2015 The Japanese Urological Association.
Hartnell, R E; Stockley, L; Keay, W; Rosec, J-P; Hervio-Heath, D; Van den Berg, H; Leoni, F; Ottaviani, D; Henigman, U; Denayer, S; Serbruyns, B; Georgsson, F; Krumova-Valcheva, G; Gyurova, E; Blanco, C; Copin, S; Strauch, E; Wieczorek, K; Lopatek, M; Britova, A; Hardouin, G; Lombard, B; In't Veld, P; Leclercq, A; Baker-Austin, C
2018-02-10
Globally, vibrios represent an important and well-established group of bacterial foodborne pathogens. The European Commission (EC) mandated the Comite de European Normalisation (CEN) to undertake work to provide validation data for 15 methods in microbiology to support EC legislation. As part of this mandated work programme, merging of ISO/TS 21872-1:2007, which specifies a horizontal method for the detection of V. parahaemolyticus and V. cholerae, and ISO/TS 21872-2:2007, a similar horizontal method for the detection of potentially pathogenic vibrios other than V. cholerae and V. parahaemolyticus was proposed. Both parts of ISO/TS 21872 utilized classical culture-based isolation techniques coupled with biochemical confirmation steps. The work also considered simplification of the biochemical confirmation steps. In addition, because of advances in molecular based methods for identification of human pathogenic Vibrio spp. classical and real-time PCR options were also included within the scope of the validation. These considerations formed the basis of a multi-laboratory validation study with the aim of improving the precision of this ISO technical specification and providing a single ISO standard method to enable detection of these important foodborne Vibrio spp.. To achieve this aim, an international validation study involving 13 laboratories from 9 countries in Europe was conducted in 2013. The results of this validation have enabled integration of the two existing technical specifications targeting the detection of the major foodborne Vibrio spp., simplification of the suite of recommended biochemical identification tests and the introduction of molecular procedures that provide both species level identification and discrimination of putatively pathogenic strains of V. parahaemolyticus by the determination of the presence of theromostable direct and direct related haemolysins. The method performance characteristics generated in this have been included in revised international standard, ISO 21872:2017, published in July 2017. Copyright © 2018. Published by Elsevier B.V.
Li, X Y; Yang, G W; Zheng, D S; Guo, W S; Hung, W N N
2015-04-28
Genetic regulatory networks are the key to understanding biochemical systems. One condition of the genetic regulatory network under different living environments can be modeled as a synchronous Boolean network. The attractors of these Boolean networks will help biologists to identify determinant and stable factors. Existing methods identify attractors based on a random initial state or the entire state simultaneously. They cannot identify the fixed length attractors directly. The complexity of including time increases exponentially with respect to the attractor number and length of attractors. This study used the bounded model checking to quickly locate fixed length attractors. Based on the SAT solver, we propose a new algorithm for efficiently computing the fixed length attractors, which is more suitable for large Boolean networks and numerous attractors' networks. After comparison using the tool BooleNet, empirical experiments involving biochemical systems demonstrated the feasibility and efficiency of our approach.
A biochemical protocol for the isolation and identification of current species of Vibrio in seafood.
Ottaviani, D; Masini, L; Bacchiocchi, S
2003-01-01
We report a biochemical method for the isolation and identification of the current species of vibrios using just one operative protocol. The method involves an enrichment phase with incubation at 30 degrees C for 8-24 h in alkaline peptone water and an isolation phase on thiosulphate-citrate-salt sucrose agar plates incubating at 30 degrees C for 24 h. Four biochemical tests and Alsina's scheme were performed for genus and species identification, respectively. All biochemical tests were optimized as regards conditions of temperature, time of incubation and media composition. The whole standardized protocol was always able to give a correct identification when applied to 25 reference strains of Vibrio and 134 field isolates. The data demonstrated that the assay method allows an efficient recovery, isolation and identification of current species of Vibrio in seafood obtaining results within 2-7 days. This method based on biochemical tests could be applicable even in basic microbiology laboratories, and can be used simultaneously to isolate and discriminate all clinically relevant species of Vibrio.
Advances in methods for detection of anaerobic ammonium oxidizing (anammox) bacteria.
Li, Meng; Gu, Ji-Dong
2011-05-01
Anaerobic ammonium oxidation (anammox), the biochemical process oxidizing ammonium into dinitrogen gas using nitrite as an electron acceptor, has only been recognized for its significant role in the global nitrogen cycle not long ago, and its ubiquitous distribution in a wide range of environments has changed our knowledge about the contributors to the global nitrogen cycle. Currently, several groups of methods are used in detection of anammox bacteria based on their physiological and biochemical characteristics, cellular chemical composition, and both 16S rRNA gene and selective functional genes as biomarkers, including hydrazine oxidoreductase and nitrite reductase encoding genes hzo and nirS, respectively. Results from these methods coupling with advances in quantitative PCR, reverse transcription of mRNA genes and stable isotope labeling have improved our understanding on the distribution, diversity, and activity of anammox bacteria in different environments both natural and engineered ones. In this review, we summarize these methods used in detection of anammox bacteria from various environments, highlight the strengths and weakness of these methods, and also discuss the new development potentials on the existing and new techniques in the future.
How to detect carbapenemase producers? A literature review of phenotypic and molecular methods.
Hammoudi, D; Moubareck, C Ayoub; Sarkis, D Karam
2014-12-01
This review describes the current state-of-art of carbapenemase detection methods. Identification of carbapenemases is first based on conventional phenotypic tests including antimicrobial susceptibility testing, modified-Hodge test and carbapenemase-inhibitor culture tests. Second, molecular characterization of carbapenemase genes by PCR sequencing is essential. Third, innovative biochemical and spectrometric detection may be applied. Copyright © 2014 Elsevier B.V. All rights reserved.
Mechergui, Arij; Achour, Wafa; Ben Hassen, Assia
2014-08-01
We aimed to compare accuracy of genus and species level identification of Neisseria spp. using biochemical testing and 16S rRNA sequence analysis. These methods were evaluated using 85 Neisseria spp. clinical isolates initially identified to the genus level by conventional biochemical tests and API NH system (Bio-Mérieux(®)). In 34 % (29/85), more than one possibility was given by 16S rRNA sequence analysis. In 6 % (5/85), one of the possibilities offered by 16S rRNA gene sequencing, agreed with the result given by biochemical testing. In 4 % (3/85), the same species was given by both methods. 16S rRNA gene sequencing results did not correlate well with biochemical tests.
Method and apparatus to image biological interactions in plants
Weisenberger, Andrew; Bonito, Gregory M.; Reid, Chantal D.; Smith, Mark Frederick
2015-12-22
A method to dynamically image the actual translocation of molecular compounds of interest in a plant root, root system, and rhizosphere without disturbing the root or the soil. The technique makes use of radioactive isotopes as tracers to label molecules of interest and to image their distribution in the plant and/or soil. The method allows for the study and imaging of various biological and biochemical interactions in the rhizosphere of a plant, including, but not limited to, mycorrhizal associations in such regions.
USDA-ARS?s Scientific Manuscript database
The methods of Sharkey and Gu for estimating the eight parameters of the Farquhar-von Caemmerer-Berry (FvBC) model were examined using generated photosynthesis versus intercellular carbon dioxide concentration (A/Ci) datasets. The generated datasets included data with (A) high accuracy, (B) normal ...
Discovering Reliable Sources of Biochemical Thermodynamic Data to Aid Students' Understanding
ERIC Educational Resources Information Center
Me´ndez, Eduardo; Cerda´, María F.
2016-01-01
Students of physical chemistry in biochemical disciplines need biochemical examples to capture the need, not always understood, of a difficult area in their studies. The use of thermodynamic data in the chemical reference state may lead to incorrect interpretations in the analysis of biochemical examples when the analysis does not include relevant…
Methods for microbiological and immunological studies of space flight crews
NASA Technical Reports Server (NTRS)
Taylor, G. R. (Editor); Zaloguev, S. N. (Editor)
1978-01-01
Systematic laboratory procedures compiled as an outgrowth of a joint U.S./U.S.S.R. microbiological-immunological experiment performed during the Apollo-Soyuz Test Project space flight are presented. Included are mutually compatible methods for the identification of aerobic and microaerophilic bacteria, yeast and yeastlike microorganisms, and filamentous fungi; methods for the bacteriophage typing of Staphylococcus aureus; and methods for determining the sensitivity of S. aureus to antibiotics. Immunological methods using blood and immunological and biochemical methods using salivary parotid fluid are also described. Formulas for media and laboratory reagents used are listed.
Biochemical transformation of coals
Lin, Mow S.; Premuzic, Eugene T.
1999-03-23
A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed.
Construction and engineering of large biochemical pathways via DNA assembler
Shao, Zengyi; Zhao, Huimin
2015-01-01
Summary DNA assembler enables rapid construction and engineering of biochemical pathways in a one-step fashion by exploitation of the in vivo homologous recombination mechanism in Saccharomyces cerevisiae. It has many applications in pathway engineering, metabolic engineering, combinatorial biology, and synthetic biology. Here we use two examples including the zeaxanthin biosynthetic pathway and the aureothin biosynthetic gene cluster to describe the key steps in the construction of pathways containing multiple genes using the DNA assembler approach. Methods for construct design, pathway assembly, pathway confirmation, and functional analysis are shown. The protocol for fine genetic modifications such as site-directed mutagenesis for engineering the aureothin gene cluster is also illustrated. PMID:23996442
In silico method for modelling metabolism and gene product expression at genome scale
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lerman, Joshua A.; Hyduke, Daniel R.; Latif, Haythem
2012-07-03
Transcription and translation use raw materials and energy generated metabolically to create the macromolecular machinery responsible for all cellular functions, including metabolism. A biochemically accurate model of molecular biology and metabolism will facilitate comprehensive and quantitative computations of an organism's molecular constitution as a function of genetic and environmental parameters. Here we formulate a model of metabolism and macromolecular expression. Prototyping it using the simple microorganism Thermotoga maritima, we show our model accurately simulates variations in cellular composition and gene expression. Moreover, through in silico comparative transcriptomics, the model allows the discovery of new regulons and improving the genome andmore » transcription unit annotations. Our method presents a framework for investigating molecular biology and cellular physiology in silico and may allow quantitative interpretation of multi-omics data sets in the context of an integrated biochemical description of an organism.« less
Biochemical transformation of solid carbonaceous material
Lin, Mow S.; Premuzic, Eugene T.
2001-09-25
A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed.
Biochemical transformation of coals
Lin, M.S.; Premuzic, E.T.
1999-03-23
A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed. 7 figs.
Rahman, Mokhlasur; Bhuiyan, N A; Kuhn, I; Ramamurthy, T; Rahman, M; Mollby, R; Nair, G Balakrish
2006-10-01
During recent years a pandemic clone of Vibrio parahaemolyticus has emerged. Isolates of this clone are distributed among several serotypes, but are genotypically related. In the present study, a phenotyping method (biochemical fingerprinting) was used to characterize pandemic and non-pandemic isolates belonging to V. parahaemolyticus. It was found that the pandemic isolates showed a high level of phenotypic homogeneity and a majority of the pandemic isolates belonged to the same biochemical phenotype, whereas non-pandemic V. parahemolyticus isolates were more heterogeneous. In conclusion, biochemical fingerprinting of V. parahaemolyticus can be used as a first screening method to differentiate between pandemic and non-pandemic isolates of V. parahaemolyticus.
NASA Astrophysics Data System (ADS)
Goñi, Miguel A.; Hedges, John I.
1995-07-01
Alkaline CuO oxidation of ubiquitous biochemicals such as proteins, polysaccharides, and lipids, yields specific products, including fatty acids, diacids, and carboxylated phenols. Oxidation of a variety of marine organisms, including macrophytes, phytoplankton, zooplankton, and bacteria, yields these CuO products in characteristic patterns that can often differentiate these biological sources. Sediments from Skan Bay (Unalaska Island, Alaska) display organic carbon and total nitrogen profiles which are consistent with three kinetically distinct pools of organic matter. The CuO fingerprints of these sediments distinguish these three pools at the molecular level, indicating a highly labile, fatty acid-rich surface organic layer of likely bacterial origin, intermediately reactive kelp debris and a background of phytoplankton remains that predominates at depth. The CuO method, which has been previously applied only to characterize cutin and lignin constituents of vascular land plants, also provides information on other types of abundant biochemicals, including those indicative of marine sources.
Measurement of biochemical oxygen demand of the leachates.
Fulazzaky, Mohamad Ali
2013-06-01
Biochemical oxygen demand (BOD) of the leachates originally from the different types of landfill sites was studied based on the data measured using the two manometric methods. The measurements of BOD using the dilution method were carried out to assess the typical physicochemical and biological characteristics of the leachates together with some other parameters. The linear regression analysis was used to predict rate constants for biochemical reactions and ultimate BOD values of the different leachates. The rate of a biochemical reaction implicated in microbial biodegradation of pollutants depends on the leachate characteristics, mass of contaminant in the leachate, and nature of the leachate. Character of leachate samples for BOD analysis of using the different methods may differ significantly during the experimental period, resulting in different BOD values. This work intends to verify effect of the different dilutions for the manometric method tests on the BOD concentrations of the leachate samples to contribute to the assessment of reaction rate and microbial consumption of oxygen.
Bailey, Jason; Piert, Morand
2017-09-09
Recently introduced Gallium-68 labeled PSMA-ligands such as HBED-CC ( 68 Ga-PSMA) have shown promise for unmet diagnostic needs in prostate cancer. 68 Ga-PSMA has demonstrated improved detection rates and specificity for prostate cancer compared to standard imaging approaches. In the setting of primary disease, 68 Ga-PSMA appears to preferentially identify treatment-relevant intermediate and high-risk prostate cancer. There is also a growing evidence that 68 Ga-PSMA positron emission tomography (PET) outperforms alternative conventional imaging methods including choline-based radiotracers for the localization of disease sites at biochemical recurrence, particularly at lower prostate-specific antigen (PSA) levels (< 1 ng/mL). However, the majority of published work lacks rigorous verification of imaging results. 68 Ga-PSMA offers significant promise for both, primary disease and biochemically recurrent prostate cancer. The evidence base to support 68 Ga-PSMA is however still underdeveloped, and more rigorous studies substantiating efficacy are needed.
CLINICAL FACTORS ASSOCIATED WITH BIOCHEMICAL ADRENAL-CORTISOL INSUFFICIENCY IN HOSPITALIZED PATIENTS
Ben-Shlomo, Anat; Mirocha, James; Liu, Ning-Ai; Sheinin, Renee C.; Melmed, Shlomo
2014-01-01
Background Diagnosis of adrenal-cortisol insufficiency is often misleading in hospitalized patients as clinical and biochemical features overlap with co-morbidities. We analyzed clinical determinants associated with a biochemical diagnosis of adrenal-cortisol insufficiency in non-ICU hospitalized patients. Methods In a retrospective cohort study we reviewed 4668 inpatients with random morning cortisol levels ≤15 μg/dL hospitalized in our center between 2003 and 2010. Using serum cortisol threshold level of 18 μg/dL 30 and/or 60 minutes after cortrosyn (250 μg) injection to define biochemical adrenal-cortisol status, we characterized and compared insufficient (n=108, serum cortisol ≤18 μg/dL) and sufficient ( n=394; serum cortisol >18 μg/dL) non-ICU hospitalized patients. Results Commonly reported clinical and routine biochemical adrenal-cortisol insufficiency features were similar between insufficient and sufficient inpatients. Biochemical adrenal-cortisol insufficiency was associated with increased frequency of liver disease, specifically hepatitis C (p=0.01) and prior orthotopic liver transplantation (p<0.001), HIV (p=0.005) and reported preexisting male hypogonadism (p<0.001) as compared to biochemical adrenal-cortisol sufficiency group. Forty percent of insufficient inpatients were not treated with glucocorticoids after diagnosis. Multivariable logistic analysis demonstrated that inpatients with higher cortisol levels (p=0.0001), higher diastolic blood pressure (p=0.05) and females (p=0.009) were more likely not to be treated, while those with previous short-term glucocorticoid treatment (p=0.002), had other co-existing endocrine diseases (p=0.005) or received an inhospital endocrinology consultation (p<0.0001) were more likely to be replaced with glucocorticoids. Conclusions Commonly reported adrenal-cortisol insufficiency features do not reliably identify hospitalized patients biochemically confirmed to have this disorder. Co-morbidities including hepatitis C, prior orthotopic liver transplantation, HIV, and reported pre-existing male hypogonadism may help identify hospitalized non-ICU patients for more rigorous adrenal insufficiency assessment. PMID:24632056
Raman spectroscopy of oral tissues: correlation of spectral and biochemical markers
NASA Astrophysics Data System (ADS)
Singh, S. P.; Krishna, C. Murali
2014-03-01
Introduction Optical spectroscopic methods are being explored as novel tools for early and non-invasive cancer diagnosis. Both ex vivo and in vivo Raman spectroscopic studies carried out in oral cancer over the past decade have demonstrated that spectra of normal tissues are rich in lipids while tumor spectra show predominance of proteins. An accurate understanding of spectral features with respect to the biochemical composition is a pre-requisite before transferring these technologies for routine clinical usage. Therefore, in the present study, we have carried out Raman and biochemical studies on same tissues to correlate spectral markers and biochemical composition of normal and tumor oral tissues. Materials and Methods Spectra of 20 pairs of normal and tumor oral tissues were acquired using fiber-optic probe coupled HE-785 Raman spectrometer. Intensity associated with lipid (1440 cm-1) and protein (1450 and 1660 cm-1) bands were computed using curve-deconvolution method. Same tissues were then subjected to biochemical estimations of major biomolecules i.e., protein, lipid and phospholipids. Results and Discussion The intensity of the lipid band was found to be higher in normal tissues with respect to tumors, and the protein band was higher in tumors compared to normal tissues. Biochemical estimation yielded similar results i.e. high protein to lipid or phospholipid ratio in tumors with-respect to normal tissues. These differences were found to be statistically significant. Conclusion Findings of curve-deconvolution and biochemical estimation correlate very well and corroborate the spectral profile noted in earlier studies.
DNA assembler, an in vivo genetic method for rapid construction of biochemical pathways
Shao, Zengyi; Zhao, Hua; Zhao, Huimin
2009-01-01
The assembly of large recombinant DNA encoding a whole biochemical pathway or genome represents a significant challenge. Here, we report a new method, DNA assembler, which allows the assembly of an entire biochemical pathway in a single step via in vivo homologous recombination in Saccharomyces cerevisiae. We show that DNA assembler can rapidly assemble a functional d-xylose utilization pathway (∼9 kb DNA consisting of three genes), a functional zeaxanthin biosynthesis pathway (∼11 kb DNA consisting of five genes) and a functional combined d-xylose utilization and zeaxanthin biosynthesis pathway (∼19 kb consisting of eight genes) with high efficiencies (70–100%) either on a plasmid or on a yeast chromosome. As this new method only requires simple DNA preparation and one-step yeast transformation, it represents a powerful tool in the construction of biochemical pathways for synthetic biology, metabolic engineering and functional genomics studies. PMID:19074487
Biochemical solubilization of toxic salts from residual geothermal brines and waste waters
Premuzic, Eugene T.; Lin, Mow S.
1994-11-22
A method of solubilizing metal salts such as metal sulfides in a geothermal sludge using mutant Thiobacilli selected for their ability to metabolize metal salts at high temperature is disclosed, The method includes the introduction of mutated Thiobacillus ferrooxidans and Thiobacillus thiooxidans to a geothermal sludge or brine. The microorganisms catalyze the solubilization of metal salts, For instance, in the case of metal sulfides, the microorganisms catalyze the solubilization to form soluble metal sulfates.
Study on color difference estimation method of medicine biochemical analysis
NASA Astrophysics Data System (ADS)
Wang, Chunhong; Zhou, Yue; Zhao, Hongxia; Sun, Jiashi; Zhou, Fengkun
2006-01-01
The biochemical analysis in medicine is an important inspection and diagnosis method in hospital clinic. The biochemical analysis of urine is one important item. The Urine test paper shows corresponding color with different detection project or different illness degree. The color difference between the standard threshold and the test paper color of urine can be used to judge the illness degree, so that further analysis and diagnosis to urine is gotten. The color is a three-dimensional physical variable concerning psychology, while reflectance is one-dimensional variable; therefore, the estimation method of color difference in urine test can have better precision and facility than the conventional test method with one-dimensional reflectance, it can make an accurate diagnose. The digital camera is easy to take an image of urine test paper and is used to carry out the urine biochemical analysis conveniently. On the experiment, the color image of urine test paper is taken by popular color digital camera and saved in the computer which installs a simple color space conversion (RGB -> XYZ -> L *a *b *)and the calculation software. Test sample is graded according to intelligent detection of quantitative color. The images taken every time were saved in computer, and the whole illness process will be monitored. This method can also use in other medicine biochemical analyses that have relation with color. Experiment result shows that this test method is quick and accurate; it can be used in hospital, calibrating organization and family, so its application prospect is extensive.
Experimental Methods for Protein Interaction Identification and Characterization
NASA Astrophysics Data System (ADS)
Uetz, Peter; Titz, Björn; Cagney, Gerard
There are dozens of methods for the detection of protein-protein interactions but they fall into a few broad categories. Fragment complementation assays such as the yeast two-hybrid (Y2H) system are based on split proteins that are functionally reconstituted by fusions of interacting proteins. Biophysical methods include structure determination and mass spectrometric (MS) identification of proteins in complexes. Biochemical methods include methods such as far western blotting and peptide arrays. Only the Y2H and protein complex purification combined with MS have been used on a larger scale. Due to the lack of data it is still difficult to compare these methods with respect to their efficiency and error rates. Current data does not favor any particular method and thus multiple experimental approaches are necessary to maximally cover the interactome of any target cell or organism.
Review on methods for determination of metallothioneins in aquatic organisms.
Shariati, Fatemeh; Shariati, Shahab
2011-06-01
One aspect of environmental degradation in coastal areas is pollution from toxic metals, which are persistent and are bioaccumulated by marine organisms, with serious public health implications. A conventional monitoring system of environmental metal pollution includes measuring the level of selected metals in the whole organism or in respective organs. However, measuring only the metal content in particular organs does not give information about its effect at the subcellular level. Therefore, the evaluation of biochemical biomarker metallothionein may be useful in assessing metal exposure and the prediction of potential detrimental effects induced by metal contamination. There are some methods for the determination of metallothioneins including spectrophotometric method, electrochemical methods, chromatography, saturation-based methods, immunological methods, electrophoresis, and RT-PCR. In this paper, different methods are discussed briefly and the comparison between them will be presented.
Using RNA Sequencing to Classify Organisms into Three Primary Kingdoms.
ERIC Educational Resources Information Center
Evans, Robert H.
1983-01-01
Using the biochemical record to class archaebacteria, eukaryotes, and eubacteria involves abstractions difficult for the concrete learner. Therefore, a method is provided in which students discover some basic tenets of biochemical classification and apply them in a "hands-on" classification problem. The method involves use of RNA…
Salem, Shady; Chang, Sam S; Clark, Peter E; Davis, Rodney; Herrell, S Duke; Kordan, Yakup; Wills, Marcia L; Shappell, Scott B; Baumgartner, Roxelyn; Phillips, Sharon; Smith, Joseph A; Cookson, Michael S; Barocas, Daniel A
2010-10-01
Whole mount processing is more resource intensive than routine systematic sampling of radical retropubic prostatectomy specimens. We compared whole mount and systematic sampling for detecting pathological outcomes, and compared the prognostic value of pathological findings across pathological methods. We included men (608 whole mount and 525 systematic sampling samples) with no prior treatment who underwent radical retropubic prostatectomy at Vanderbilt University Medical Center between January 2000 and June 2008. We used univariate and multivariate analysis to compare the pathological outcome detection rate between pathological methods. Kaplan-Meier curves and the log rank test were used to compare the prognostic value of pathological findings across pathological methods. There were no significant differences between the whole mount and the systematic sampling groups in detecting extraprostatic extension (25% vs 30%), positive surgical margins (31% vs 31%), pathological Gleason score less than 7 (49% vs 43%), 7 (39% vs 43%) or greater than 7 (12% vs 13%), seminal vesicle invasion (8% vs 10%) or lymph node involvement (3% vs 5%). Tumor volume was higher in the systematic sampling group and whole mount detected more multiple surgical margins (each p <0.01). There were no significant differences in the likelihood of biochemical recurrence between the pathological methods when patients were stratified by pathological outcome. Except for estimated tumor volume and multiple margins whole mount and systematic sampling yield similar pathological information. Each method stratifies patients into comparable risk groups for biochemical recurrence. Thus, while whole mount is more resource intensive, it does not appear to result in improved detection of clinically important pathological outcomes or prognostication. Copyright © 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
A biochemical method for assessing the neurotoxic effects of misonidazole in the rat.
Rose, G. P.; Dewar, A. J.; Stratford, I. J.
1980-01-01
A proven biochemical method for assessing chemically induced neurotoxicity has been applied to the study of the toxic effects of misonidazole (MISO) in the rat. This involves the fluorimetric measurement of beta-glucuronidase and beta-galactosidase activities in homogenates of rat nervous tissue. The tissues analysed were sciatic/posterior tibial nerve (SPTN) cut into 4 sections, trigeminal ganglia and cerebellum. MISO administered i.p. to Wistar rats in doses greater than 300 mg/kg/day for 7 consecutive days produced maximal increases in both beta-glucuronidase and beta-galactosidase activities in th SPTN at 4 weeks (140-180% of control values). The highest increases were associated with the most distal secretion of the nerve. Significant enzyme-activity changes were also found in the trigeminal ganglia and cerebellum of MISO-dosed rats. The greatest activity occurred 4-5 weeks after dosing, and was dose-related. It is concluded that, in the rat, MISO can produce biochemical changes consistent with a dying-back peripheral neuropathy, and biochemical changes suggestive of cerebellar damage. This biochemical approach would appear to offer a convenient quantitative method for the detection of neurotoxic effects of other potential radio-sensitizing drugs. PMID:7459223
Biochemical solubilization of toxic salts from residual geothermal brines and waste waters
Premuzic, E.T.; Lin, M.S.
1994-11-22
A method of solubilizing metal salts such as metal sulfides in a geothermal sludge using mutant Thiobacilli selected for their ability to metabolize metal salts at high temperature is disclosed. The method includes the introduction of mutated Thiobacillus ferrooxidans and Thiobacillus thiooxidans to a geothermal sludge or brine. The microorganisms catalyze the solubilization of metal salts. For instance, in the case of metal sulfides, the microorganisms catalyze the solubilization to form soluble metal sulfates. 54 figs.
Peeks, Fabian; Steunenberg, Thomas A H; de Boer, Foekje; Rubio-Gozalbo, M Estela; Williams, Monique; Burghard, Rob; Rajas, Fabienne; Oosterveer, Maaike H; Weinstein, David A; Derks, Terry G J
2017-09-01
To study heterogeneity between patients with glycogen storage disease type Ia (GSD Ia), a rare inherited disorder of carbohydrate metabolism caused by the deficiency of glucose-6-phosphatase (G6Pase). Descriptive retrospective study of longitudinal clinical and biochemical data and long-term complications in 20 GSD Ia patients. We included 11 patients with homozygous G6PC mutations and siblings from four families carrying identical G6PC genotypes. To display subtle variations for repeated triglyceride measurements with respect to time for individual patients, CUSUM-analysis graphs were constructed. Patients with different homozygous G6PC mutations showed important differences in height, BMI, and biochemical parameters (i.e., lactate, uric acid, triglyceride, and cholesterol concentrations). Furthermore, CUSUM-analysis predicts and displays subtle changes in longitudinal blood triglyceride concentrations. Siblings in families also displayed important differences in biochemical parameters (i.e., lactate, uric acid, triglycerides, and cholesterol concentrations) and long-term complications (i.e., liver adenomas, nephropathy, and osteopenia/osteoporosis). Differences between GSD Ia patients reflect large clinical and biochemical heterogeneity. Heterogeneity between GSD Ia patients with homozygous G6PC mutations indicate an important role of the G6PC genotype/mutations. Differences between affected siblings suggest an additional role (genetic and/or environmental) of modifying factors defining the GSD Ia phenotype. CUSUM-analysis can facilitate single-patient monitoring of metabolic control and future application of this method may improve precision medicine for patients both with GSD and remaining inherited metabolic diseases.
Markovina, Stephanie; Weschenfelder, Débora Cristina; Gay, Hiram; McCandless, Audrey; Carey, Bethany; DeWees, Todd; Knutson, Nels; Michalski, Jeff
2014-01-01
To evaluate serum testosterone and the incidence of biochemical hypogonadism in men treated with intensity modulated radiation therapy (IMRT) for prostate cancer. Serum testosterone was evaluated prospectively in 51 men at pretreatment and at 6-month time points for 2 years posttreatment with IMRT for prostate cancer. Forty-one patients (80%) were treated with definitive intent and 10 patients with postprostatectomy radiation to median total doses of 7380 cGy and 6480 cGy, respectively. No patients received hormone therapy within 12 months of any serum testosterone value. Biochemical hypogonadism was defined as a total serum testosterone level ≤ 300 ng/dL. Incidental testicular dose was calculated using planning software when computed tomography information was available (n = 21) and using a published method of estimation when not available (n = 24), and was available for 45 patients. A statistically significant decrease in testosterone, though small in magnitude, was seen at 6 months after completion of therapy, with no significant difference by 1 year after completion of therapy. There was no increase in biochemical hypogonadism after IMRT. Below-normal pretreatment testosterone was not associated with a transient decrease. Estimated cumulative testicular dose, including dose from daily imaging, was not associated with a change in testosterone, nor was radiation therapy prescription dose or treatment intent (postoperative vs definitive). The mild transient decrease in serum testosterone following IMRT monotherapy for prostate cancer is not associated with new biochemical hypogonadism.
Garrigues, P; Narbonne, J F; Lafaurie, M; Ribera, D; Lemaire, P; Raoux, C; Michel, X; Salaun, J P; Monod, J L; Romeo, M
1993-11-01
The GICBEM (Groupe Interface Chimie Biologie des Ecosystèmes Marins) program consists of an evaluation of the ecosystem health status in the Mediterranean Sea mainly based on chemical and biochemical approaches. Specific chemical contaminants (polycyclic aromatic hydrocarbons (PAH), polychlorobiphenyls (PCB), heavy metals) in waters, sediments, and related biotransformation indicators in target organisms (mussels, fish) have been selected for a complete survey of the coastal waters. In order to provide an appropriate sampling program for standardization for each sampling cruise, various aspects have been studied: (a) parameters for the choice of the sample sites; (b) ways of collection the samples (waters, sediments, marine organisms); and (c) preparation of the samples for a short term storage on board ship and for further analyses in the ground laboratory. Methods of preparation and storage of the samples are described and could be used to initiate an environmental banking program including both possible retrospective analyses of chemical pollutants and biochemical indicators. Moreover, the correlation between chemicals (PAH) and biochemical (mixed function oxygenase activities) parameters has been studied and this demonstrates the capability of the enzyme activities as reliable pollution biomarkers.
NASA Astrophysics Data System (ADS)
Zusfahair; Ningsih, D. R.; Fatoni, A.; Pertiwi, D. S.
2018-04-01
Urease is enzyme that plays a role in nitrogen metabolism during plant germination. Plants that produce a lot of urease are grains. This study used asparagus bean as source of urease. The purpose of this research is to learn the effect of germination time on the activity of urease enzyme from asparagus bean and its biochemical properties. The research was started by germination of asparagus bean on day 2, 4, 6, 8, 10 and 12. Asparagus bean sprouts were extracted using acetone and separated by centrifugation to obtain the crude extract of urease. The biochemical properties of the crude extract of urease was further determined including: the effect of temperature, pH, substrate concentration, and metal addition to urease activity. The urease activity is determined by the Nessler method. The germination time of asparagus bean in yielding urease enzyme reached the optimum activity on the 8th day with activity value of 593.7 U/mL. The biochemical properties of urease from asparagus bean have optimum activity at 35 °C, pH 7.0 and substrate concentration 0.125% with activity value of 600 U/mL. Addition of CaCl2, SnCl2 and ZnCl2 metals decrease the activity of urease.
MARCKS promotes invasion and is associated with biochemical recurrence in prostate cancer
Dorris, Emma; O'Neill, Amanda; Hanrahan, Karen; Treacy, Ann; Watson, R. William
2017-01-01
Background Overtreatment of low-grade prostate cancer is a recognised problem for clinicians and patients. However, under-treatment runs the risk of missing the opportunity for cure in those who could benefit. Identification of new biomarkers of disease progression, including metastases, is required to better stratify and appropriately treat these patients. The ability to predict if prostate cancer will recur is an important clinical question that would impact treatment options for patients. Studies in other cancers have associated MARCKS with metastasis. Methods Tissue microarrays of local prostatectomy samples from a cohort of biochemical recurrent and non-biochemical recurrent tumours were assayed for MARCKS protein expression. Prostate cancer cell lines were transfected with siRNA targeting MARCKS or a control and functional endpoints of migration, invasion, proliferation, viability and apoptosis were measured. Actin was visualised by fluorescent microscopy and evidence of a cadherin switch and activation of the AKT pathway were assayed. Results MARCKS was upregulated in biochemical recurrent patients compared to non-biochemical recurrent. Knockdown of MARCKS reduced migration and invasion of prostate cancer cells, reduced MMP9 mRNA expression, as well as decreasing cell spreading and increased cell:cell adhesion in prostate cancer cell colonies. Knockdown of MARCKS had no effect on proliferation, viability or apoptosis of the prostate cancer cells. Conclusions In conclusion, MARCKS promotes migration and invasion and is associated with biochemical recurrence in localised prostate cancer tumours. The mechanisms by which this occurs have yet to be fully elucidated but lack of a cadherin switch indicates it is not via epithelial-to-mesenchymal transition. Actin rearrangement indicates that MARCKS promotes invasion through regulating the architecture of the cell. PMID:29069765
Studies in neuroendocrine pharmacology
NASA Technical Reports Server (NTRS)
Maickel, R. P.
1976-01-01
The expertise and facilities available within the Medical Sciences Program section on Pharmacology were used along with informational input from various NASA sources to study areas relevant to the manned space effort. Topics discussed include effects of drugs on deprivation-induced fluid consumption, brain biogenic amines, biochemical responses to stressful stimuli, biochemical and behavioral pharmacology of amphetamines, biochemical and pharmacological studies of analogues to biologically active indole compounds, chemical pharmacology: drug metabolism and disposition, toxicology, and chemical methodology. Appendices include a bibliography, and papers submitted for publication or already published.
Surrogate biochemical markers: precise measurement for strategic drug and biologics development.
Lee, J W; Hulse, J D; Colburn, W A
1995-05-01
More efficient drug and biologics development is necessary for future success of pharmaceutical and biotechnology companies. One way to achieve this objective is to use rationally selected surrogate markers to improve the early decision-making process. Using typical clinical chemistry methods to measure biochemical markers may not ensure adequate precision and reproducibility. In contrast, using analytical methods that meet good laboratory practices along with rational selection and validation of biochemical markers can give those who use them a competitive advantage over those who do not by providing meaningful data for earlier decision making.
Community structure in networks
NASA Astrophysics Data System (ADS)
Newman, Mark
2004-03-01
Many networked systems, including physical, biological, social, and technological networks, appear to contain ``communities'' -- groups of nodes within which connections are dense, but between which they are sparser. The ability to find such communities in an automated fashion could be of considerable use. Communities in a web graph for instance might correspond to sets of web sites dealing with related topics, while communities in a biochemical network or an electronic circuit might correspond to functional units of some kind. We present a number of new methods for community discovery, including methods based on ``betweenness'' measures and methods based on modularity optimization. We also give examples of applications of these methods to both computer-generated and real-world network data, and show how our techniques can be used to shed light on the sometimes dauntingly complex structure of networked systems.
NASA Astrophysics Data System (ADS)
Thanh, Vo Hong; Marchetti, Luca; Reali, Federico; Priami, Corrado
2018-02-01
The stochastic simulation algorithm (SSA) has been widely used for simulating biochemical reaction networks. SSA is able to capture the inherently intrinsic noise of the biological system, which is due to the discreteness of species population and to the randomness of their reciprocal interactions. However, SSA does not consider other sources of heterogeneity in biochemical reaction systems, which are referred to as extrinsic noise. Here, we extend two simulation approaches, namely, the integration-based method and the rejection-based method, to take extrinsic noise into account by allowing the reaction propensities to vary in time and state dependent manner. For both methods, new efficient implementations are introduced and their efficiency and applicability to biological models are investigated. Our numerical results suggest that the rejection-based method performs better than the integration-based method when the extrinsic noise is considered.
Carmichael, John D; Broder, Michael S; Cherepanov, Dasha; Chang, Eunice; Mamelak, Adam; Said, Qayyim; Neary, Maureen P; Bonert, Vivien
2017-08-04
Acromegaly is a rare, slowly progressive disorder resulting from excessive growth hormone (GH) production by a pituitary somatotroph tumor. The objective of this study was to examine acromegaly treatment outcomes during long-term care at a specialized pituitary center in patients presenting with lack of biochemical control. Data came from an acromegaly registry at the Cedars-Sinai Medical Center Pituitary Center (center). Acromegaly patients included in this study were those who presented biochemically-uncontrolled for care at the center. Biochemical control status, based on serum insulin-like growth factor-1 values, was determined at presentation and at study end. Patient characteristics and acromegaly treatments were reported before and after presentation by presenting treatment status and final biochemical control status. Data on long-term follow-up were recorded from 1985 through June 2013. Seventy-four patients presented uncontrolled: 40 untreated (54.1%) and 34 (45.9%) previously-treated. Mean (SD) age at diagnosis was 43.2 (14.7); 32 (43.2%) were female patients. Of 65 patients with tumor size information, 59 (90.8%) had macroadenomas. Prior treatments among the 34 previously-treated patients were pituitary surgery alone (47.1%), surgery and medication (41.2%), and medication alone (11.8%). Of the 40 patients without prior treatment, 82.5% achieved control by study end. Of the 34 with prior treatment, 50% achieved control by study end. This observational study shows that treatment outcomes of biochemically-uncontrolled acromegaly patients improve with directed care, particularly for those that initially present untreated. Patients often require multiple modalities of treatment, many of which are offered with the highest quality at specialized pituitary centers. Despite specialized care, some patients were not able to achieve biochemical control with methods of treatment that were available at the time of their treatment, showing the need for additional treatment options.
Donovan, Rory M.; Tapia, Jose-Juan; Sullivan, Devin P.; Faeder, James R.; Murphy, Robert F.; Dittrich, Markus; Zuckerman, Daniel M.
2016-01-01
The long-term goal of connecting scales in biological simulation can be facilitated by scale-agnostic methods. We demonstrate that the weighted ensemble (WE) strategy, initially developed for molecular simulations, applies effectively to spatially resolved cell-scale simulations. The WE approach runs an ensemble of parallel trajectories with assigned weights and uses a statistical resampling strategy of replicating and pruning trajectories to focus computational effort on difficult-to-sample regions. The method can also generate unbiased estimates of non-equilibrium and equilibrium observables, sometimes with significantly less aggregate computing time than would be possible using standard parallelization. Here, we use WE to orchestrate particle-based kinetic Monte Carlo simulations, which include spatial geometry (e.g., of organelles, plasma membrane) and biochemical interactions among mobile molecular species. We study a series of models exhibiting spatial, temporal and biochemical complexity and show that although WE has important limitations, it can achieve performance significantly exceeding standard parallel simulation—by orders of magnitude for some observables. PMID:26845334
Isolation and identification of lactic acid bacteria from fermented red dragon fruit juices.
Ong, Yien Yien; Tan, Wen Siang; Rosfarizan, Mohamad; Chan, Eng Seng; Tey, Beng Ti
2012-10-01
Red dragon fruit or red pitaya is rich in potassium, fiber, and antioxidants. Its nutritional properties and unique flesh color have made it an attractive raw material of various types of food products and beverages including fermented beverages or enzyme drinks. In this study, phenotypic and genotypic methods were used to confirm the identity of lactic acid bacteria (LAB) appeared in fermented red dragon fruit (Hylocereus polyrhizus) beverages. A total of 21 isolates of LAB were isolated and characterized. They belonged to the genus of Enterococcus based on their biochemical characteristics. The isolates can be clustered into two groups by using the randomly amplified polymorphic DNA method. Nucleotide sequencing and restriction fragment length polymorphism of the 16S rRNA region suggested that they were either Enterococcus faecalis or Enterococcus durans. Current research revealed the use of biochemical analyses and molecular approaches to identify the microbial population particularly lactic acid bacteria from fermented red dragon fruit juices. © 2012 Institute of Food Technologists®
Label-free cell separation and sorting in microfluidic systems
Gossett, Daniel R.; Weaver, Westbrook M.; Mach, Albert J.; Hur, Soojung Claire; Tse, Henry Tat Kwong; Lee, Wonhee; Amini, Hamed
2010-01-01
Cell separation and sorting are essential steps in cell biology research and in many diagnostic and therapeutic methods. Recently, there has been interest in methods which avoid the use of biochemical labels; numerous intrinsic biomarkers have been explored to identify cells including size, electrical polarizability, and hydrodynamic properties. This review highlights microfluidic techniques used for label-free discrimination and fractionation of cell populations. Microfluidic systems have been adopted to precisely handle single cells and interface with other tools for biochemical analysis. We analyzed many of these techniques, detailing their mode of separation, while concentrating on recent developments and evaluating their prospects for application. Furthermore, this was done from a perspective where inertial effects are considered important and general performance metrics were proposed which would ease comparison of reported technologies. Lastly, we assess the current state of these technologies and suggest directions which may make them more accessible. Figure A wide range of microfluidic technologies have been developed to separate and sort cells by taking advantage of differences in their intrinsic biophysical properties PMID:20419490
The rotating spectrometer: Biotechnology for cell separations
NASA Technical Reports Server (NTRS)
Noever, David A.
1991-01-01
An instrument for biochemical studies, called the rotating spectrometer, separates previously inseparable cell cultures. The rotating spectrometer is intended for use in pharmacological studies which require fractional splitting of heterogeneous cell cultures based on cell morphology and swimming behavior. As a method to separate and concentrate cells in free solution, the rotating method requires active organism participation and can effectively split the large class of organisms known to form spontaneous patterns. Examples include the biochemical star, an organism called Tetrahymena pyriformis. Following focusing in a rotating frame, the separation is accomplished using different radial dependencies of concentrated algal and protozoan species. The focusing itself appears as concentric rings and arises from the coupling between swimming direction and Coriolis forces. A dense cut is taken at varying radii, and extraction is replenished at an inlet. Unlike standard separation and concentrating techniques such as filtration or centrifugation, the instrument is able to separate motile from immotile fractions. For a single pass, typical split efficiencies can reach 200 to 300 percent compared to the inlet concentration.
The rotating spectrometer: New biotechnology for cell separations
NASA Technical Reports Server (NTRS)
Noever, David A.; Matsos, Helen C.
1990-01-01
An instrument for biochemical studies, called the rotating spectrometer, separates previously inseparable cell cultures. The rotating spectrometer is intended for use in pharmacological studies which require fractional splitting of heterogeneous cell cultures based on cell morphology and swimming behavior. As a method to separate and concentrate cells in free solution, the rotating method requires active organism participation and can effectively split the large class of organisms known to form spontaneous patterns. Examples include the biochemical star, an organism called Tetrahymena pyriformis. Following focusing in a rotated frame, the separation is accomplished using different radial dependencies of concentrated algal and protozoan species. The focusing itself appears as concentric rings and arises from the coupling between swimming direction and Coriolis forces. A dense cut is taken at varying radii and extraction is replenished at an inlet. Unlike standard separation and concentrating techniques such as filtration or centrifugation, the instrument is able to separate motile from immotile fractions. For a single pass, typical split efficiencies can reach 200 to 300 percent compared to the inlet concentration.
NASA Astrophysics Data System (ADS)
Murphy, Patrick Thomas
The purpose of this research was twofold: (i) to develop a system for screening lignocellulosic biomass feedstocks for biochemical conversion to biofuels and (ii) to evaluate brown midrib corn stover as feedstock for ethanol production. In the first study (Chapter 2), we investigated the potential of corn stover from bm1-4 hybrids for increased ethanol production and reduced pretreatment intensity compared to corn stover from the isogenic normal hybrid. Corn stover from hybrid W64A X A619 and respective isogenic bm hybrids was pretreated by aqueous ammonia steeping using ammonium hydroxide concentrations from 0 to 30%, by weight, and the resulting residues underwent simultaneous saccharification and cofermentation (SSCF) to ethanol. Dry matter (DM) digested by SSCF increased with increasing ammonium hydroxide concentration across all genotypes (P>0.0001) from 277 g kg-1 DM in the control to 439 g kg-1 DM in the 30% ammonium hydroxide pretreatment. The bm corn stover materials averaged 373 g kg-1 DM of DM digested by SSCF compared with 335 g kg-1 DM for the normal corn stover (P<0.0001). Of the bm mutations, bm3 had (i) the greatest effect on cell-wall carbohydrate hydrolysis of corn stover, (ii) the lowest initial cell-wall carbohydrate concentration, (iii) the lowest dry matter remaining after pretreatment, and (iv) the highest amount of monosaccharides released during enzymatic hydrolysis. However, bm corn stover did not reduce the severity of aqueous ammonia steeping pretreatment needed to maximize DM hydrolysis during SSCF compared with normal corn stover. In the remaining studies (Chapters 3 thru 5), a system for analyzing the quality of lignocellulosic biomass feedstocks for biochemical conversion to biofuels (i.e., pretreatment, enzymatic hydrolysis, and fermentation) was developed. To accomplish this, a carbohydrate availability model was developed to characterize feedstock quality. The model partitions carbohydrates within a feedstock material into fractions based on their availability to be converted to fermentable sugars, including non-structural carbohydrates (CN) (monosaccharides, starches, oligosaccharides), biochemically available carbohydrates (CB) (structural carbohydrates susceptible to enzymatic hydrolysis) with an associated 1st-order availability rate constant (k B) and unavailable carbohydrates (CU) (hemicellulose and cellulose in close association with lignin). The model partitions the noncarbohydrate dry matter into extractives, lignin, and ash. Quality parameters were determined using a biomass quality assay that combined established wet-chemistry analyses techniques, including total non-structural carbohydrates (TNC), alcohol insoluble residue (AIR), simultaneous saccharification and fermentation (SSCF), and Klason lignin. The next study evaluated multiple high-throughput (HTP) modifications to the original assay methods, including (i) using filter bags with batch sample processing, (ii) replacement of AIR with neutral detergent fiber (NDF) as a cell-wall isolation procedure, and (iii) elimination of the fermentation organism in the SSCF procedures used to determine biochemically available carbohydrates. The original and the HTP assay methods were compared using corn cobs, hybrid poplar, kenaf, and switchgrass. Biochemically available carbohydrates increased with the HTP methods in the corn cobs, hybrid poplar, and switchgrass, but remained the same in the kenaf. Total available carbohydrates increased and unavailable carbohydrates decreased with the HTP methods in the corn cobs and switchgrass and remained the same in the hybrid poplar and kenaf. There were no differences in total carbohydrates (CT) between the two methods. The final study evaluated the variability of biomass quality parameters in a set of corn stover samples, and developed calibration equations for determining parameter values using near infrared reflectance spectroscopy (NIRS). Fifty-two corn stover samples harvested in Iowa and Wisconsin in 2005 and 2006 were analyzed using the HTP assay for determining feedstock quality for biochemical conversion. Non-structural carbohydrates ranged from 84 to 155 g kg -1 DM, CB ranged from 354 to 557 g kg-1 DM, kB ranged from 0.20 to 0.33 h-1, CA ranged from 463 to 699 g kg-1 DM, and neutral detergent lignin (NDL) ranged from 32 to 74 g kg-1 DM. Significant differences (P<0.0001) among samples were observed for all parameters, except for the availability rate constant of CB. (Abstract shortened by UMI.)
Bertozzi, Carolyn C [Albany, CA; Yarema, Kevin J [Albany, CA; Mahal, Lara K [Berkeley, CA
2008-04-01
Methods for making the functionalized glycoconjugates include (a) contacting a cell with a first monosaccharide, and (b) incubating the cell under conditions whereby the cell (i) internalizes the first monosaccharide, (ii) biochemically processes the first monosaccharide into a second saccharide, (iii) conjugates the saccharide to a carrier to form a glycoconjugate, and (iv) extracellularly expresses the glycoconjugate to form an extracellular glycoconjugate comprising a selectively reactive functional group. Methods for forming products at a cell further comprise contacting the functional group of the extracellularly expressed glycoconjugate with an agent which selectively reacts with the functional group to form a product. Subject compositions include cyto-compatible monosaccharides comprising a nitrogen or ether linked functional group selectively reactive at a cell surface and compositions and cells comprising such saccharides.
Park, Jung Jae; Kim, Chan Kyo; Park, Sung Yoon; Park, Byung Kwan; Lee, Hyun Moo; Cho, Seong Whi
2014-05-01
The purpose of this study is to retrospectively investigate whether pretreatment multiparametric MRI findings can predict biochemical recurrence in patients who underwent radical prostatectomy (RP) for localized prostate cancer. In this study, 282 patients with biopsy-proven prostate cancer who received RP underwent pretreatment MRI using a phased-array coil at 3 T, including T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced MRI (DCE-MRI). MRI variables included apparent tumor presence on combined imaging sequences, extracapsular extension, and tumor size on DWI or DCE-MRI. Clinical variables included baseline prostate-specific antigen (PSA) level, clinical stage, and Gleason score at biopsy. The relationship between clinical and imaging variables and biochemical recurrence was evaluated using Cox regression analysis. After a median follow-up of 26 months, biochemical recurrence developed in 61 patients (22%). Univariate analysis revealed that all the imaging and clinical variables were significantly associated with biochemical recurrence (p < 0.01). On multivariate analysis, however, baseline PSA level (p = 0.002), Gleason score at biopsy (p = 0.024), and apparent tumor presence on combined T2WI, DWI, and DCE-MRI (p = 0.047) were the only significant independent predictors of biochemical recurrence. Of the independent predictors, apparent tumor presence on combined T2WI, DWI, and DCE-MRI showed the highest hazard ratio (2.38) compared with baseline PSA level (hazard ratio, 1.05) and Gleason score at biopsy (hazard ratio, 1.34). The apparent tumor presence on combined T2WI, DWI, and DCE-MRI of pretreatment MRI is an independent predictor of biochemical recurrence after RP. This finding may be used to construct a predictive model for biochemical recurrence after surgery.
[Biochemical indicators of anaphylactic shock and the application in forensic medicine].
Mi, Li; Chen, Jie; Gao, Wei-Min; Du, Zhong-Bo; Cao, Zhi-Peng; Zhang, Yuan; Zhu, Bao-Li
2014-04-01
Fatal anaphylactic shock is common in forensic practice. However, it is difficult to diagnose for lacking specific pathological and morphologic changes in forensic autopsy. The application of some biochemical indicators is of great significance. This paper reviews the biological characteristics of some biochemical indicators and detection methods. The forensic application, problems and prospects of these indicators are also introduced in details. The stable biochemical indicators, IgE, tryptase and chymase, show great potential and advantages in the identification of fatal anaphylactic shock in forensic medicine.
Kokaly, R.F.; Asner, Gregory P.; Ollinger, S.V.; Martin, M.E.; Wessman, C.A.
2009-01-01
For two decades, remotely sensed data from imaging spectrometers have been used to estimate non-pigment biochemical constituents of vegetation, including water, nitrogen, cellulose, and lignin. This interest has been motivated by the important role that these substances play in physiological processes such as photosynthesis, their relationships with ecosystem processes such as litter decomposition and nutrient cycling, and their use in identifying key plant species and functional groups. This paper reviews three areas of research to improve the application of imaging spectrometers to quantify non-pigment biochemical constituents of plants. First, we examine recent empirical and modeling studies that have advanced our understanding of leaf and canopy reflectance spectra in relation to plant biochemistry. Next, we present recent examples of how spectroscopic remote sensing methods are applied to characterize vegetation canopies, communities and ecosystems. Third, we highlight the latest developments in using imaging spectrometer data to quantify net primary production (NPP) over large geographic areas. Finally, we discuss the major challenges in quantifying non-pigment biochemical constituents of plant canopies from remotely sensed spectra.
Complexity and performance of on-chip biochemical assays
NASA Astrophysics Data System (ADS)
Kopf-Sill, Anne R.; Nikiforov, Theo; Bousse, Luc J.; Nagle, Rob; Parce, J. W.
1997-03-01
The use of microchips for performing biochemical processes has the potential to reduce reagent use and thus assay costs, increase throughput, and automate complex processes. We are building a multifunctional platform that provides sensing and actuation functions for a variety of microchip- based biochemical and analytical processes. Here we describe recent experiments that include on-chip dilution, reagent mixing, reaction, separation, and detection for important classes of biochemical assays. Issues in chip design and control are discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steinkamp, J.A.; Wilson, J.S.; Svitra, Z.V.
1979-02-01
This report summarizes ongoing experiments to develop cytological and biochemical indicators for measuring damage to respiratory tract cells of experimental animals exposed by inhalation to environmental toxic agents. The specific goal is to apply flow cytometric methods to analyze and detect changes in lung epithelium as a function of exposure to toxic agents associated with the production and utilization of synthetic fuels from oil shale and coal. During the past 6 months, hamsters were exposed to raw and spent oil shale particulates, silica dust, and ozone, and DNA content measurements were performed on lung cell samples. Although initial shale exposuresmore » did not yield the expected results, recent data show atypical changes in DNA content per cell distributions. Ozone exposures also were expanded to include DNA measurements and cytology, ranging up to 72 h postexposure. Progress was achieved in developing a new method for quantitating pulmonary macrophage phagocytosis in rats using micron-sized fluorescent spheres. New methods for determining alkaline phosphatase, DNA content, and protein also were under development. Plans are to continue developing cytological and biochemical markers for measuring atypical cellular changes, including macrophage function, and to emphasize exposing experimental animals to particulates and gaseous agents for studying dose-damage relationships.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Romani, R.J.; Maxie, E.C.; Robinson, B.J.
1962-10-31
A study was nmade of the effects of radiation processing on the keeping qualities of pears. Both gamma and beta exposure prolonged the ripening process in the fruit. Data are included on the effects of radiation on respiration of the fruit. Methods are described for preparing enzyme extracts and lyophilized material for biochemical studies. (C.H.)
[Diagnostic imaging of changes of the canine intervertebral disc].
Harder, Lisa K
2016-10-12
Intervertebral disc degeneration can cause intervertebral disc herniation. Diagnostic imaging, including radiography, computed tomography and magnetic resonance imaging, is the most important tool in diagnosis. Firstly, an overview of macroscopic and biochemical physiology and pathology of the intervertebral disc will be given. Subsequently, the physics of diagnostic imaging and the appearance of intervertebral disc degeneration and displacement in several imaging methods are described.
Mabry, T J
2001-12-01
The elucidation by NMR and chemical methods of the unique structure of betanidin, the aglycon of the red-violet beet pigment betanin, forty years ago at the University of Zürich, Switzerland, was the beginning of my plant chemistry research program. Many of the same chemical and spectral techniques developed in Zürich have been used at The University of Texas at Austin for the structure analysis of members of many other classes of natural products including especially flavonoids, terpenoids, and alkaloids. Investigations at UT-Austin have concerned many topics such as biochemical and molecular systematics, biosynthetic pathways, structure-activity relationships, and the medicinal importance of natural products and included studies of antiviral proteins in the genus Phytolacca and neurotoxic nonprotein amino acids from cycads and other sources. Following the betalain story and an account of the early development of my UT-Austin biochemical systematic program, the Phytolacca and neurotoxin investigations are discussed herein.
Gender Differences in Cardiovascular Disease: Hormonal and Biochemical Influences
Pérez-López, Faustino R.; Larrad-Mur, Luis; Kallen, Amanda; Chedraui, Peter; Taylor, Hugh S.
2011-01-01
Objective Atherosclerosis is a complex process characterized by an increase in vascular wall thickness owing to the accumulation of cells and extracellular matrix between the endothelium and the smooth muscle cell wall. There is evidence that females are at lower risk of developing cardiovascular disease (CVD) as compared to males. This has led to an interest in examining the contribution of genetic background and sex hormones to the development of CVD. The objective of this review is to provide an overview of factors, including those related to gender, that influence CVD. Methods Evidence analysis from PubMed and individual searches concerning biochemical and endocrine influences and gender differences, which affect the origin and development of CVD. Results Although still controversial, evidence suggests that hormones including estradiol and androgens are responsible for subtle cardiovascular changes long before the development of overt atherosclerosis. Conclusion Exposure to sex hormones throughout an individual's lifespan modulates many endocrine factors involved in atherosclerosis. PMID:20460551
Blanch, A R; Galofré, B; Lucena, F; Terradillos, A; Vilanova, X; Ribas, F
2007-03-01
To compare the bacterial coliforms detected from occurrences in three zones of a water distribution system supplied by two separate water sources. Conventional and standardized protocols for identifying enterobacterial populations were applied. Additional tests to confirm isolates were included. Analyses of diversity and population similarity were performed using the Phene Plate System, a miniaturized biochemical phenotyping method. Isolates were identified by the API 20E system in tandem with biochemical phenotyping. A total of 16 576 samples were taken from the water distribution system, with 1416 isolates analysed. A low number of coliform occurrences were observed (2%). Escherichia coli was not detected in either water origin or in Zone 2 samples; however, in Zones 1 and 3 a low number of cases of E. coli were recorded. The percentages of E. coli depended on the identification criteria. Eight biochemical profiles for coliform populations were defined according to the results of the confirmative tests. There was a high diversity among these populations in the three zones studied, although no significant variations in their composition (associated with occurrences in the different zones) were observed. Klebsiella oxytoca was the most commonly detected species irrespective of zone, although seven other enterobacterial genera were also found. Analysis of the enzymatic activity of beta-glucuronidase or application of the criteria established in the norm ISO 9308-1, in tandem with thermotolerance was needed to evaluate the occurrence of E. coli in the distribution systems. Detected occurrences of bacterial coliforms could be associated with re-growth patterns for specific sampling points in the distribution system. Seasonal differences, independent of the studied zones, were observed. Biochemical phenotyping of bacterial coliforms was shown to be a useful method on the characterization of occurrences in water distribution systems.
Methods and Devices for Micro-Isolation, Extraction, and/or Analysis of Microscale Components
NASA Technical Reports Server (NTRS)
Wade, Lawrence A. (Inventor); Kartalov, Emil P. (Inventor); Taylor, Clive (Inventor); Shibata, Darryl (Inventor)
2014-01-01
Provided herein are devices and methods for the micro-isolation of biological cellular material. A micro-isolation apparatus described can comprise a photomask that protects regions of interest against DNA-destroying illumination. The micro-isolation apparatus can further comprise photosensitive material defining access wells following illumination and subsequent developing of the photosensitive material. The micro-isolation apparatus can further comprise a chambered microfluidic device comprising channels providing access to wells defined in photosensitive material. The micro-isolation apparatus can comprise a chambered microfluidic device without access wells defined in photosensitive material where valves control the flow of gases or liquids through the channels of the microfluidic device. Also included are methods for selectively isolating cellular material using the apparatuses described herein, as are methods for biochemical analysis of individual regions of interest of cellular material using the devices described herein. Further included are methods of making masking arrays useful for the methods described herein.
McMahan, Lanakila; Grunden, Amy M; Devine, Anthony A; Sobsey, Mark D
2012-04-15
The sensitivity and specificity of the H(2)S test to detect fecal bacteria in water has been variable and uncertain in previous studies, partly due to its presence-absence results. Furthermore, in groundwater samples false-positive results have been reported, with H(2)S-positive samples containing no fecal coliforms or Escherichia coli. False-negative results also have been reported in other studies, with H(2)S-negative samples found to contain E. coli. Using biochemical and molecular methods and a novel quantitative test format, this research identified the types and numbers of microbial community members present in natural water samples, including fecal indicators and pathogens as well as other bacteria. Representative water sources tested in this study included cistern rainwater, a protected lake, and wells in agricultural and forest settings. Samples from quantitative H(2)S tests of water were further cultured for fecal bacteria by spread plating onto the selective media for detection and isolation of Aeromonas spp., E. coli, Clostridium spp., H(2)S-producers, and species of Salmonella and Shigella. Isolates were then tested for H(2)S production, and identified to the genus and species level using biochemical methods. Terminal Restriction Fragment Length Polymorphisms (TRFLP) was the molecular method employed to quantitatively characterize microbial community diversity. Overall, it was shown that water samples testing positive for H(2)S bacteria also had bacteria of likely fecal origin and waters containing fecal pathogens also were positive for H(2)S bacteria. Of the microorganisms isolated from natural water, greater than 70 percent were identified using TRFLP analysis to reveal a relatively stable group of organisms whose community composition differed with water source and over time. These results further document the validity of the H(2)S test for detecting and quantifying fecal contamination of water. Copyright © 2011 Elsevier Ltd. All rights reserved.
A systematic petri net approach for multiple-scale modeling and simulation of biochemical processes.
Chen, Ming; Hu, Minjie; Hofestädt, Ralf
2011-06-01
A method to exploit hybrid Petri nets for modeling and simulating biochemical processes in a systematic way was introduced. Both molecular biology and biochemical engineering aspects are manipulated. With discrete and continuous elements, the hybrid Petri nets can easily handle biochemical factors such as metabolites concentration and kinetic behaviors. It is possible to translate both molecular biological behavior and biochemical processes workflow into hybrid Petri nets in a natural manner. As an example, penicillin production bioprocess is modeled to illustrate the concepts of the methodology. Results of the dynamic of production parameters in the bioprocess were simulated and observed diagrammatically. Current problems and post-genomic perspectives were also discussed.
Lee, Jessica J Y; Gottlieb, Michael M; Lever, Jake; Jones, Steven J M; Blau, Nenad; van Karnebeek, Clara D M; Wasserman, Wyeth W
2018-05-01
Phenomics is the comprehensive study of phenotypes at every level of biology: from metabolites to organisms. With high throughput technologies increasing the scope of biological discoveries, the field of phenomics has been developing rapid and precise methods to collect, catalog, and analyze phenotypes. Such methods have allowed phenotypic data to be widely used in medical applications, from assisting clinical diagnoses to prioritizing genomic diagnoses. To channel the benefits of phenomics into the field of inborn errors of metabolism (IEM), we have recently launched IEMbase, an expert-curated knowledgebase of IEM and their disease-characterizing phenotypes. While our efforts with IEMbase have realized benefits, taking full advantage of phenomics requires a comprehensive curation of IEM phenotypes in core phenomics projects, which is dependent upon contributions from the IEM clinical and research community. Here, we assess the inclusion of IEM biochemical phenotypes in a core phenomics project, the Human Phenotype Ontology. We then demonstrate the utility of biochemical phenotypes using a text-based phenomics method to predict gene-disease relationships, showing that the prediction of IEM genes is significantly better using biochemical rather than clinical profiles. The findings herein provide a motivating goal for the IEM community to expand the computationally accessible descriptions of biochemical phenotypes associated with IEM in phenomics resources.
Identification of paraoxonase 3 in rat liver microsomes: purification and biochemical properties.
Rodrigo, Lourdes; Gil, Fernando; Hernandez, Antonio F; Lopez, Olga; Pla, Antonio
2003-01-01
Three paraoxonase genes (PON1, PON2 and PON3) have been described so far in mammals. Although considerable information is available regarding PON1, little is known about PON2 and PON3. PON3 has been isolated recently from rabbit serum [Draganov, Stetson, Watson, Billecke and La Du (2000) J. Biol. Chem. 275, 33435-33442] and liver [Ozols (1999) Biochem. J. 338, 265-275]. In the present study, we have identified the presence of PON3 in rat liver microsomes and a method for the purification to homogeneity is presented. PON3 has been purified 177-fold to apparent homogeneity with a final specific activity of 461 units/mg using a method consisting of seven steps: solubilization of the microsomal fraction, hydroxyapatite adsorption, chromatography on DEAE-Sepharose CL-6B, non-specific affinity chromatography on Cibacron Blue 3GA, two DEAE-cellulose steps and a final affinity chromatography on concanavalin A-Sepharose. SDS/PAGE of the final preparation indicated a single protein-staining band with an apparent molecular mass of 43 kDa. The isolated protein was identified by nanoelectrospray MS. Internal amino acid sequences of several peptides were determined and compared with those of human, rabbit and mouse PON3, showing a high similarity. Some biochemical properties of PON3 were also studied, including optimum pH, K(m) and heat and pH stability. PMID:12946270
Scalable Parameter Estimation for Genome-Scale Biochemical Reaction Networks
Kaltenbacher, Barbara; Hasenauer, Jan
2017-01-01
Mechanistic mathematical modeling of biochemical reaction networks using ordinary differential equation (ODE) models has improved our understanding of small- and medium-scale biological processes. While the same should in principle hold for large- and genome-scale processes, the computational methods for the analysis of ODE models which describe hundreds or thousands of biochemical species and reactions are missing so far. While individual simulations are feasible, the inference of the model parameters from experimental data is computationally too intensive. In this manuscript, we evaluate adjoint sensitivity analysis for parameter estimation in large scale biochemical reaction networks. We present the approach for time-discrete measurement and compare it to state-of-the-art methods used in systems and computational biology. Our comparison reveals a significantly improved computational efficiency and a superior scalability of adjoint sensitivity analysis. The computational complexity is effectively independent of the number of parameters, enabling the analysis of large- and genome-scale models. Our study of a comprehensive kinetic model of ErbB signaling shows that parameter estimation using adjoint sensitivity analysis requires a fraction of the computation time of established methods. The proposed method will facilitate mechanistic modeling of genome-scale cellular processes, as required in the age of omics. PMID:28114351
The use of biochemical methods in extraterrestrial life detection
NASA Astrophysics Data System (ADS)
McDonald, Gene
2006-08-01
Instrument development for in situ extraterrestrial life detection focuses primarily on the ability to distinguish between biological and non-biological material, mostly through chemical analysis for potential biosignatures (e.g., biogenic minerals, enantiomeric excesses). In constrast, biochemical analysis techniques commonly applied to Earth life focus primarily on the exploration of cellular and molecular processes, not on the classification of a given system as biological or non-biological. This focus has developed because of the relatively large functional gap between life and non-life on Earth today. Life on Earth is very diverse from an environmental and physiological point of view, but is highly conserved from a molecular point of view. Biochemical analysis techniques take advantage of this similarity of all terrestrial life at the molecular level, particularly through the use of biologically-derived reagents (e.g., DNA polymerases, antibodies), to enable analytical methods with enormous sensitivity and selectivity. These capabilities encourage consideration of such reagents and methods for use in extraterrestrial life detection instruments. The utility of this approach depends in large part on the (unknown at this time) degree of molecular compositional differences between extraterrestrial and terrestrial life. The greater these differences, the less useful laboratory biochemical techniques will be without significant modification. Biochemistry and molecular biology methods may need to be "de-focused" in order to produce instruments capable of unambiguously detecting a sufficiently wide range of extraterrestrial biochemical systems. Modern biotechnology tools may make that possible in some cases.
Developments in commercially produced microbials at Biochem Products
John Lublinkhof; Douglas H. Ross
1985-01-01
Biochem Products is part of a large industrial and scientific family - the Solvay Group. Solvay, headquartered in Brussels, Belgium is a multinational company with 46,000 employees worldwide. In the U.S., our working partners include a large polymer manufacturer, a peroxygen producer and a leading poultry and animal health products company. Biochem Products is a...
Timescale analysis of rule-based biochemical reaction networks
Klinke, David J.; Finley, Stacey D.
2012-01-01
The flow of information within a cell is governed by a series of protein-protein interactions that can be described as a reaction network. Mathematical models of biochemical reaction networks can be constructed by repetitively applying specific rules that define how reactants interact and what new species are formed upon reaction. To aid in understanding the underlying biochemistry, timescale analysis is one method developed to prune the size of the reaction network. In this work, we extend the methods associated with timescale analysis to reaction rules instead of the species contained within the network. To illustrate this approach, we applied timescale analysis to a simple receptor-ligand binding model and a rule-based model of Interleukin-12 (IL-12) signaling in näive CD4+ T cells. The IL-12 signaling pathway includes multiple protein-protein interactions that collectively transmit information; however, the level of mechanistic detail sufficient to capture the observed dynamics has not been justified based upon the available data. The analysis correctly predicted that reactions associated with JAK2 and TYK2 binding to their corresponding receptor exist at a pseudo-equilibrium. In contrast, reactions associated with ligand binding and receptor turnover regulate cellular response to IL-12. An empirical Bayesian approach was used to estimate the uncertainty in the timescales. This approach complements existing rank- and flux-based methods that can be used to interrogate complex reaction networks. Ultimately, timescale analysis of rule-based models is a computational tool that can be used to reveal the biochemical steps that regulate signaling dynamics. PMID:21954150
Biochemical Engineering Fundamentals
ERIC Educational Resources Information Center
Bailey, J. E.; Ollis, D. F.
1976-01-01
Discusses a biochemical engineering course that is offered as part of a chemical engineering curriculum and includes topics that influence the behavior of man-made or natural microbial or enzyme reactors. (MLH)
Davies, Sarah K; Fearn, Sarah; Allsopp, Luke P; Harrison, Freya; Ware, Ecaterina; Diggle, Stephen P; Filloux, Alain; McPhail, David S; Bundy, Jacob G
2017-01-01
Bacterial biofilms are groups of bacteria that exist within a self-produced extracellular matrix, adhering to each other and usually to a surface. They grow on medical equipment and inserts such as catheters and are responsible for many persistent infections throughout the body, as they can have high resistance to many antimicrobials. Pseudomonas aeruginosa is an opportunistic pathogen that can cause both acute and chronic infections and is used as a model for research into biofilms. Direct biochemical methods of imaging of molecules in bacterial biofilms are of high value in gaining a better understanding of the fundamental biology of biofilms and biochemical gradients within them. Time of flight-secondary-ion mass spectrometry (TOF-SIMS) is one approach, which combines relatively high spatial resolution and sensitivity and can perform depth profiling analysis. It has been used to analyze bacterial biofilms but has not yet been used to study the distribution of antimicrobials (including antibiotics and the antimicrobial metal gallium) within biofilms. Here we compared two methods of imaging of the interior structure of P. aeruginosa in biological samples using TOF-SIMS, looking at both antimicrobials and endogenous biochemicals: cryosectioning of tissue samples and depth profiling to give pseudo-three-dimensional (pseudo-3D) images. The sample types included both simple biofilms grown on glass slides and bacteria growing in tissues in an ex vivo pig lung model. The two techniques for the 3D imaging of biofilms are potentially valuable complementary tools for analyzing bacterial infection. IMPORTANCE Modern analytical techniques are becoming increasingly important in the life sciences; imaging mass spectrometry offers the opportunity to gain unprecedented amounts of information on the distribution of chemicals in samples-both xenobiotics and endogenous compounds. In particular, simultaneous imaging of antibiotics (and other antimicrobial compounds) and bacterium-derived metabolites in complex biological samples could be very important in the future for helping to understand how sample matrices impact the survival of bacteria under antibiotic challenge. We have shown that an imaging mass spectrometric technique, TOF-SIMS, will be potentially extremely valuable for this kind of research in the future.
Rodríguez, S Alvarez; Arias Fúnez, F; Bueno Bravo, C; Rodríguez-Patrón Rodríguez, R; Sanz Mayayo, E; Palacios, V Hevia; Burgos Revilla, F J
2014-01-01
Purpose. Published data about cryotherapy for prostate cancer (PC) treatment are based on case series with a lack of clinical trials and the inexistence of a validated definition of biochemical failure. A prospective study with standardized followup protocol was conducted in our institution. Material and Methods. Prospective study of a series of cases including 108 patients diagnosed with localized PC at clinical stage T1c-T2c treated by primary cryoablation and median followup of 61 months. Criteria of biochemical recurrence were unified according to the American Society for Therapeutic Radiology and Oncology (ASTRO). End points were biochemical progression-free survival (BPFS), cancer-specific survival, and overall survival. Rate of complications was reported. Results. The BPFS for low-, medium-, and high-risk patients was 96.4%, 91.2%, and 62.2%, respectively. Cancer-specific survival was 98.1%. Overall survival reached 94.4%. Complications included incontinence in 5.6%, urinary tract obstruction in 1.9%, urethral sloughing in 5.6%, haematuria in 1.9%, perineal pain in 11.1%, and prostatorectal fistula in 0.9%. Erectile disfunction was found in 98.1%. Conclusions. Cryotherapy is an effective and minimally invasive treatment for primary PC in well-selected cases, with low surgical risk and good results in terms of BPFS, cancer-specific survival, and overall survival.
Rodríguez, S. Alvarez; Arias Fúnez, F.; Bueno Bravo, C.; Rodríguez-Patrón Rodríguez, R.; Sanz Mayayo, E.; Palacios, V. Hevia; Burgos Revilla, F. J.
2014-01-01
Purpose. Published data about cryotherapy for prostate cancer (PC) treatment are based on case series with a lack of clinical trials and the inexistence of a validated definition of biochemical failure. A prospective study with standardized followup protocol was conducted in our institution. Material and Methods. Prospective study of a series of cases including 108 patients diagnosed with localized PC at clinical stage T1c-T2c treated by primary cryoablation and median followup of 61 months. Criteria of biochemical recurrence were unified according to the American Society for Therapeutic Radiology and Oncology (ASTRO). End points were biochemical progression-free survival (BPFS), cancer-specific survival, and overall survival. Rate of complications was reported. Results. The BPFS for low-, medium-, and high-risk patients was 96.4%, 91.2%, and 62.2%, respectively. Cancer-specific survival was 98.1%. Overall survival reached 94.4%. Complications included incontinence in 5.6%, urinary tract obstruction in 1.9%, urethral sloughing in 5.6%, haematuria in 1.9%, perineal pain in 11.1%, and prostatorectal fistula in 0.9%. Erectile disfunction was found in 98.1%. Conclusions. Cryotherapy is an effective and minimally invasive treatment for primary PC in well-selected cases, with low surgical risk and good results in terms of BPFS, cancer-specific survival, and overall survival. PMID:24693437
Experimental Systems to Study Yeast Pexophagy.
Yamashita, Shun-Ichi; Oku, Masahide; Sakai, Yasuyoshi; Fujiki, Yukio
2017-01-01
Peroxisome abundance is tightly regulated according to the physiological contexts, through regulations of both proliferation and degradation of the organelles. Here, we describe detailed methods to analyze processes for autophagic degradation of peroxisomes, termed pexophagy, in yeast organisms. The assay systems include a method for biochemical detection of pexophagy completion, and one for microscopic visualization of specialized membrane structures acting in pexophagy. As a model yeast organism utilized in studies of pexophagy, the methylotrophic yeast Komagataella phaffii (Pichia pastoris) is referred to in this chapter and related information on the studies with baker's yeast (Saccharomyces cerevisiae) is also included. The described techniques facilitate elucidation of molecular machineries for pexophagy and understanding of peroxisome-selective autophagic pathways.
Analysis of Chromobacterium sp. natural isolates from different Brazilian ecosystems
Lima-Bittencourt, Cláudia I; Astolfi-Filho, Spartaco; Chartone-Souza, Edmar; Santos, Fabrício R; Nascimento, Andréa MA
2007-01-01
Background Chromobacterium violaceum is a free-living bacterium able to survive under diverse environmental conditions. In this study we evaluate the genetic and physiological diversity of Chromobacterium sp. isolates from three Brazilian ecosystems: Brazilian Savannah (Cerrado), Atlantic Rain Forest and Amazon Rain Forest. We have analyzed the diversity with molecular approaches (16S rRNA gene sequences and amplified ribosomal DNA restriction analysis) and phenotypic surveys of antibiotic resistance and biochemistry profiles. Results In general, the clusters based on physiological profiles included isolates from two or more geographical locations indicating that they are not restricted to a single ecosystem. The isolates from Brazilian Savannah presented greater physiologic diversity and their biochemical profile was the most variable of all groupings. The isolates recovered from Amazon and Atlantic Rain Forests presented the most similar biochemical characteristics to the Chromobacterium violaceum ATCC 12472 strain. Clusters based on biochemical profiles were congruent with clusters obtained by the 16S rRNA gene tree. According to the phylogenetic analyses, isolates from the Amazon Rain Forest and Savannah displayed a closer relationship to the Chromobacterium violaceum ATCC 12472. Furthermore, 16S rRNA gene tree revealed a good correlation between phylogenetic clustering and geographic origin. Conclusion The physiological analyses clearly demonstrate the high biochemical versatility found in the C. violaceum genome and molecular methods allowed to detect the intra and inter-population diversity of isolates from three Brazilian ecosystems. PMID:17584942
Vinnakota, Kalyan C.; Wu, Fan; Kushmerick, Martin J.; Beard, Daniel A.
2009-01-01
The operation of biochemical systems in vivo and in vitro is strongly influenced by complex interactions between biochemical reactants and ions such as H+, Mg2+, K+, and Ca2+. These are important second messengers in metabolic and signaling pathways that directly influence the kinetics and thermodynamics of biochemical systems. Herein we describe the biophysical theory and computational methods to account for multiple ion binding to biochemical reactants and demonstrate the crucial effects of ion binding on biochemical reaction kinetics and thermodynamics. In simulations of realistic systems, the concentrations of these ions change with time due to dynamic buffering and competitive binding. In turn, the effective thermodynamic properties vary as functions of cation concentrations and important environmental variables such as temperature and overall ionic strength. Physically realistic simulations of biochemical systems require incorporating all of these phenomena into a coherent mathematical description. Several applications to physiological systems are demonstrated based on this coherent simulation framework. PMID:19216922
A Program on Biochemical and Biomedical Engineering.
ERIC Educational Resources Information Center
San, Ka-Yiu; McIntire, Larry V.
1989-01-01
Presents an introduction to the Biochemical and Biomedical Engineering program at Rice University. Describes the development of the academic and enhancement programs, including organizational structure and research project titles. (YP)
A biochemical landscape of A-to-I RNA editing in the human brain transcriptome
Sakurai, Masayuki; Ueda, Hiroki; Yano, Takanori; Okada, Shunpei; Terajima, Hideki; Mitsuyama, Toutai; Toyoda, Atsushi; Fujiyama, Asao; Kawabata, Hitomi; Suzuki, Tsutomu
2014-01-01
Inosine is an abundant RNA modification in the human transcriptome and is essential for many biological processes in modulating gene expression at the post-transcriptional level. Adenosine deaminases acting on RNA (ADARs) catalyze the hydrolytic deamination of adenosines to inosines (A-to-I editing) in double-stranded regions. We previously established a biochemical method called “inosine chemical erasing” (ICE) to directly identify inosines on RNA strands with high reliability. Here, we have applied the ICE method combined with deep sequencing (ICE-seq) to conduct an unbiased genome-wide screening of A-to-I editing sites in the transcriptome of human adult brain. Taken together with the sites identified by the conventional ICE method, we mapped 19,791 novel sites and newly found 1258 edited mRNAs, including 66 novel sites in coding regions, 41 of which cause altered amino acid assignment. ICE-seq detected novel editing sites in various repeat elements as well as in short hairpins. Gene ontology analysis revealed that these edited mRNAs are associated with transcription, energy metabolism, and neurological disorders, providing new insights into various aspects of human brain functions. PMID:24407955
State-of-the-Art of (Bio)Chemical Sensor Developments in Analytical Spanish Groups
Plata, María Reyes; Contento, Ana María; Ríos, Angel
2010-01-01
(Bio)chemical sensors are one of the most exciting fields in analytical chemistry today. The development of these analytical devices simplifies and miniaturizes the whole analytical process. Although the initial expectation of the massive incorporation of sensors in routine analytical work has been truncated to some extent, in many other cases analytical methods based on sensor technology have solved important analytical problems. Many research groups are working in this field world-wide, reporting interesting results so far. Modestly, Spanish researchers have contributed to these recent developments. In this review, we summarize the more representative achievements carried out for these groups. They cover a wide variety of sensors, including optical, electrochemical, piezoelectric or electro-mechanical devices, used for laboratory or field analyses. The capabilities to be used in different applied areas are also critically discussed. PMID:22319260
Unification of some biochemical methods of research in the pre- and post-flight periods
NASA Technical Reports Server (NTRS)
Tigranyan, R. A.
1980-01-01
The biochemical methods for determination of various parameters and factors during pre- and post-flight periods, as used by American and Soviet teams dealing with space flight medicine are compared. The emphasis is on the exchange of information on the study of the blood and urine content of space travelers before and after space flight. A series of electrolytic, enzymatic, and hormonal factors is discussed.
Evaporation control research, 1955-58
Cruse, Robert R.; Harbeck, Guy Earl
1960-01-01
One hundred fifty-two compounds and compositions of matter were screened as potential evaporation retardants. The homologous straight-chain fatty alkanols are considered the best materials for retardants. Several methods of application of the alkanols to the reservoir surface were investigated. Although wick-type drippers for the application of liquids and cage rafts for the application of solids appear to be the most promising methods from an economic standpoint, both methods have serious disadvantages. Considerable study was given to reducing biochemical oxidation of the evaporation retardants. Copper in several forms was found adequate as a bacteriostatic agent but posed a potential hazard because of its toxicity. Many other bactericides that were tested were also toxic. Two sets of large-scale field tests have been completed and several others are still in progress. On the larger reservoirs, the reduction of evaporation was not more than 20 percent under the prevailing conditions and the application procedure used. Three major practical problems remain; namely, the effects and action of wind on the monofilm, the effects of biochemical oxidation, and the most effective method of application. Fundamental problems remaining include the effects of various impurities, and the composition of the best evaporation retardant; the long-range effects of monofilms on the limnology of a reservoir, including the transfer of oxygen and carbon dioxide; toxicological aspects of all components of any evaporation-retardant composition, plus toxicology of any composition chosen for large-scale use; and further studies of the calorimetry and thermodynamics involved in the mechanism of evaporation and its reduction by a monofilm.
[Isolation and identification of Cronobacter (Enterobacter sakazakii) strains from food].
Dong, Xiaohui; Li, Chengsi; Wu, Qingping; Zhang, Jumei; Mo, Shuping; Guo, Weipeng; Yang, Xiaojuan; Xu, Xiaoke
2013-05-04
This study aimed to detect and quantify Cronobacter in 300 powdered milk samples and 50 non-powdered milk samples. Totally, 24 Cronobacter (formerly Enterobacter sakazakii) strains isolated from powdered milk and other foods were identified and confirmed. Cronobacter strains were detected quantitatively using most probable number (MPN) method and molecular detection method. We identified 24 Cronobacter strains using biochemical patterns, including indole production and dulcitol, malonate, melezitose, turanose, and myo-Inositol utilization. Of the 24 strains, their 16S rRNA genes were sequenced, and constructed phylogenetic tree by N-J (Neighbour-Joining) with the 16S rRNA gene sequences of 17 identified Cronobacter strains and 10 non-Cronobacter strains. Quantitative detection showed that Cronobacter strains were detected in 23 out of 350 samples yielding 6.6% detection rate. Twenty-four Cronobacter strains were isolated from 23 samples and the Cronobacter was more than 100 MPN/100g in 4 samples out of 23 samples. The 24 Cronobacter spp. isolates strains were identified and confirmed, including 19 Cronobacter sakazakii strains, 2 C. malonaticus strains, 2 C. dubliensis subsp. lactaridi strains, and 1 C. muytjensii strain. The combination of molecular detection method and most probable number (MPN) method could be suitable for the detection of Cronobacter in powdered milk, with low rate of contamination and high demand of quantitative detection. 24 isolated strains were confirmed and identified by biochemical patterns and molecular technology, and C. sakazakii could be the dominant species. The problem of Cronobacter in powdered milk should be a hidden danger to nurseling, and should catch the government and consumer's attention.
Designing Epigenome Editors: Considerations of Biochemical and Locus Specificities.
Sen, Dilara; Keung, Albert J
2018-01-01
The advent of locus-specific protein recruitment technologies has enabled a new class of studies in chromatin biology. Epigenome editors enable biochemical modifications of chromatin at almost any specific endogenous locus. Their locus specificity unlocks unique information including the functional roles of distinct modifications at specific genomic loci. Given the growing interest in using these tools for biological and translational studies, there are many specific design considerations depending on the scientific question or clinical need. Here we present and discuss important design considerations and challenges regarding the biochemical and locus specificities of epigenome editors. These include how to account for the complex biochemical diversity of chromatin; control for potential interdependency of epigenome editors and their resultant modifications; avoid sequestration effects; quantify the locus specificity of epigenome editors; and improve locus specificity by considering concentration, affinity, avidity, and sequestration effects.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Diez, Patricia; Vogelius, Ivan S.; Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792
2010-07-15
Purpose: A new method is presented for synthesizing dose-response data for biochemical control of prostate cancer according to study design (randomized vs. nonrandomized) and risk group (low vs. intermediate-high). Methods and Materials: Nine published prostate cancer dose escalation studies including 6,539 patients were identified in the MEDLINE and CINAHL databases and reviewed to assess the relationship between dose and biochemical control. A novel method of analysis is presented in which the normalized dose-response gradient, {gamma}{sub 50}, is estimated for each study and subsequently synthesized across studies. Our method does not assume that biochemical control rates are directly comparable between studies.more » Results: Nonrandomized studies produced a statistically significantly higher {gamma}{sub 50} than randomized studies for intermediate- to high-risk patients ({gamma}{sub 50} = 1.63 vs. {gamma}{sub 50} = 0.93, p = 0.03) and a borderline significantly higher ({gamma}{sub 50} = 1.78 vs. {gamma}{sub 50} = 0.56, p = 0.08) for low-risk patients. No statistically significant difference in {gamma}{sub 50} was found between low- and intermediate- to high-risk patients (p = 0.31). From the pooled data of low and intermediate- to high-risk patients in randomized trials, we obtain the overall best estimate of {gamma}{sub 50} = 0.84 with 95% confidence interval 0.54-1.15. Conclusions: Nonrandomized studies overestimate the steepness of the dose-response curve as compared with randomized trials. This is probably the result of stage migration, improved treatment techniques, and a shorter follow-up in higher dose patients that were typically entered more recently. This overestimation leads to inflated expectations regarding the benefit from dose-escalation and could lead to underpowered clinical trials. There is no evidence of a steeper dose response for intermediate- to high-risk compared with low-risk patients.« less
2010-01-01
Purpose To evaluate the long-term safety of polyethylene glycol (PEG) 4000 in children with constipation, particularly the biochemical aspects of safety. Methods Medical records were evaluated, and 100 children, who had been taking PEG 4000 for more than 6 months, and who had been under clinical and biochemical monitoring, were enrolled. Ages; 6.11±3.12 years, Duration of therapy; 16.93±7.02 months, dose of PEG 4000; 0.72±0.21 g/kg/d. Results None of the children complained of clinical adverse effect. The first biochemical test was performed at 8.05 months after beginning of PEG 4000. Serum phosphate (SP) value was high in 10 children, and leucopenia was noted in one child. The second test was performed in 44 children at 7.57 months after the first test. The SP value was high in four children, including the three children whose initial SP value was high and one new child. Six out of 10 children with high initial SP value became normal and one was lost. Hypernatremia was noted in one child. The third test was done in 15 children at 7.5 months after the second test. The SP value of the new child from the second test was high, but became normal after finishing treatment. Two out of 3 children with high SP value at the second test became normal and one was lost. The fourth test was done in 2 children few months after the third test. All of the results were normal. There were no relation between duration of therapy and hyperphosphatemia, or between dose of PEG 4000 and hyperphosphatemia. Conclusions PEG 4000 is safe for long-term therapy in children with constipation with respect to biochemical parameters. PMID:21189949
A scalable moment-closure approximation for large-scale biochemical reaction networks
Kazeroonian, Atefeh; Theis, Fabian J.; Hasenauer, Jan
2017-01-01
Abstract Motivation: Stochastic molecular processes are a leading cause of cell-to-cell variability. Their dynamics are often described by continuous-time discrete-state Markov chains and simulated using stochastic simulation algorithms. As these stochastic simulations are computationally demanding, ordinary differential equation models for the dynamics of the statistical moments have been developed. The number of state variables of these approximating models, however, grows at least quadratically with the number of biochemical species. This limits their application to small- and medium-sized processes. Results: In this article, we present a scalable moment-closure approximation (sMA) for the simulation of statistical moments of large-scale stochastic processes. The sMA exploits the structure of the biochemical reaction network to reduce the covariance matrix. We prove that sMA yields approximating models whose number of state variables depends predominantly on local properties, i.e. the average node degree of the reaction network, instead of the overall network size. The resulting complexity reduction is assessed by studying a range of medium- and large-scale biochemical reaction networks. To evaluate the approximation accuracy and the improvement in computational efficiency, we study models for JAK2/STAT5 signalling and NFκB signalling. Our method is applicable to generic biochemical reaction networks and we provide an implementation, including an SBML interface, which renders the sMA easily accessible. Availability and implementation: The sMA is implemented in the open-source MATLAB toolbox CERENA and is available from https://github.com/CERENADevelopers/CERENA. Contact: jan.hasenauer@helmholtz-muenchen.de or atefeh.kazeroonian@tum.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28881983
[Two cases of personal identification from dental information].
Yamaguchi, T; Yamada, Y; Ohtani, S; Kogure, T; Nagao, M; Takatori, T; Ohira, H; Yamamoto, I; Watanabe, A
1997-08-01
We describe two cases in which unknown bodies were positively identified from dental information and biochemical examination using tooth materials. In one case, a charred body was positively identified with little effort by comparison of antemortem dental records (dental chart and dental X-ray film) with postmortem data. In the other case, although the unknown individual had dental treatment, the police were unable to obtain the antemortem dental records of the victim. We then conducted biochemical analysis of teeth, facilitating personal identification using DNA analysis and age estimation based on aspartic acid racemization. The mutation obtained from the sequence of mtDNA and the genotypes of HLADQ alpha, HPRTB and ABO blood groups including the data for estimated age supported the kinship between the unknown individual and his mother. The data for maternally inherited mtDNA were of great importance in this case, since it was possible to obtain DNA from the mother. Dental identification in one of the most accurate methods of personal identification if suitable antemortem records are available. In the absence of such records, biochemical analysis of teeth also makes it possible to increase the probability of correct personal identification.
A century of enzyme kinetic analysis, 1913 to 2013.
Johnson, Kenneth A
2013-09-02
This review traces the history and logical progression of methods for quantitative analysis of enzyme kinetics from the 1913 Michaelis and Menten paper to the application of modern computational methods today. Following a brief review of methods for fitting steady state kinetic data, modern methods are highlighted for fitting full progress curve kinetics based upon numerical integration of rate equations, including a re-analysis of the original Michaelis-Menten full time course kinetic data. Finally, several illustrations of modern transient state kinetic methods of analysis are shown which enable the elucidation of reactions occurring at the active sites of enzymes in order to relate structure and function. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
How important is thermodynamics for identifying elementary flux modes?
Peres, Sabine; Jolicœur, Mario; Moulin, Cécile
2017-01-01
We present a method for computing thermodynamically feasible elementary flux modes (tEFMs) using equilibrium constants without need of internal metabolite concentrations. The method is compared with the method based on a binary distinction between reversible and irreversible reactions. When all reactions are reversible, adding the constraints based on equilibrium constants reduces the number of elementary flux modes (EFMs) by a factor of two. Declaring in advance some reactions as irreversible, based on reliable biochemical expertise, can in general reduce the number of EFMs by a greater factor. But, even in this case, computing tEFMs can rule out some EFMs which are biochemically irrelevant. We applied our method to two published models described with binary distinction: the monosaccharide metabolism and the central carbon metabolism of Chinese hamster ovary cells. The results show that the binary distinction is in good agreement with biochemical observations. Moreover, the suppression of the EFMs that are not consistent with the equilibrium constants appears to be biologically relevant. PMID:28222104
Microfluidic devices for the controlled manipulation of small volumes
Ramsey, J Michael [Knoxville, TN; Jacobson, Stephen C [Knoxville, TN
2003-02-25
A method for conducting a broad range of biochemical analyses or manipulations on a series of nano- to subnanoliter reaction volumes and an apparatus for carrying out the same are disclosed. The method and apparatus are implemented on a fluidic microchip to provide high serial throughput. The method and device of the invention also lend themselves to multiple parallel analyses and manipulation to provide greater throughput for the generation of biochemical information. In particular, the disclosed device is a microfabricated channel device that can manipulate nanoliter or subnanoliter biochemical reaction volumes in a controlled manner to produce results at rates of 1 to 10 Hz per channel. The individual reaction volumes are manipulated in serial fashion analogous to a digital shift register. The method and apparatus according to this invention have application to such problems as screening molecular or cellular targets using single beads from split-synthesis combinatorial libraries, screening single cells for RNA or protein expression, genetic diagnostic screening at the single cell level, or performing single cell signal transduction studies.
Mansoor, Sana; Collyer, Elizabeth; Alkhouri, Naim
2015-06-01
Nonalcoholic fatty liver disease (NAFLD) and its spectrum ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) and fibrosis have been increasing in the pediatric population. The presence and severity of fibrosis in patients with NAFLD are important prognostic factors for the risk of disease progression to cirrhosis. The gold standard for staging liver fibrosis is a liver biopsy. However, given the risks of this procedure, especially in the pediatric population, the development of noninvasive markers to diagnose and monitor progression of NAFLD is desirable. This paper will review recently developed noninvasive methods for diagnosing liver fibrosis in children with NAFLD. These include simple fibrosis scores, advanced biochemical markers, and radiologic imaging studies. Simple fibrosis scores use readily available laboratory tests; available one include AST/ALT ratio, AST to platelet ratio index (APRI), fibrosis (FIB)-4 index, NAFLD fibrosis score (NFS), pediatric NAFLD fibrosis index (PNFI), and pediatric NALFD fibrosis score (PNFS). Advanced biochemical markers include biomarkers of hepatocyte cell death such as cytokeratin 18 fragment levels, and markers of extracellular matrix turnover such as the Enhanced Liver Fibrosis (ELF) test and hyaluronic acid. Radiologic imaging studies estimate liver stiffness as a surrogate for liver fibrosis; these include transient elastography (TE), magnetic resonance elastography (MRE), and acoustic radiation force impulse imaging (ARFI).
Hsu, Bing-Mu; Wu, Shu-Fen; Huang, Shih-Wei; Tseng, Yu-Jung; Ji, Dar-Der; Chen, Jung-Sheng; Shih, Feng-Cheng
2010-02-01
Both Shigella spp. and enteroinvasive Escherichia coli (EIEC) are important human pathogens that are responsible for the majority of cases of endemic bacillary dysentery. However, they are difficult to identify and differentiate by biochemical tests or molecular methods alone. In this study, we developed a procedure to detect Shigella spp. and EIEC from environmental water samples using membrane filtration followed by nutrient broth enrichment, isolation using selective culture plates, and identification of the invasion plasmid antigen H (ipaH) gene by PCR amplification and DNA sequencing. Finally, we used a biochemical test and a serological assay to differentiate between Shigella and EIEC. Among the 93 water samples from nine reservoirs and one watershed, 76 (81.7%) water samples of culture plates had candidate colonies of Shigella and EIEC and 5 water samples were positive (5.4%) for a Shigella- and EIEC-specific polymerase chain reaction targeting the ipaH gene. Guided by the molecular method, the biochemical test, and the serological assay, 11 ipaH gene-positive isolates from 5 water samples were all identified as EIEC. (c) 2009 Elsevier Ltd. All rights reserved.
Nanau, Radu M.; Neuman, Manuela G.
2015-01-01
Background: The quantitative, measurable detection of drinking is important for the successful treatment of alcohol misuse in transplantation of patients with alcohol disorders, people living with human immunodeficiency virus that need to adhere to medication, and special occupational hazard offenders, many of whom continually deny drinking. Their initial misconduct usually leads to medical problems associated with drinking, impulsive social behavior, and drunk driving. The accurate identification of alcohol consumption via biochemical tests contributes significantly to the monitoring of drinking behavior. Methods: A systematic review of the current methods used to measure biomarkers of alcohol consumption was conducted using PubMed and Google Scholar databases (2010–2015). The names of the tests have been identified. The methods and publications that correlate between the social instruments and the biochemical tests were further investigated. There is a clear need for assays standardization to ensure the use of these biochemical tests as routine biomarkers. Findings: Alcohol ingestion can be measured using a breath test. Because alcohol is rapidly eliminated from the circulation, the time for detection by this analysis is in the range of hours. Alcohol consumption can alternatively be detected by direct measurement of ethanol concentration in blood or urine. Several markers have been proposed to extend the interval and sensitivities of detection, including ethyl glucuronide and ethyl sulfate in urine, phosphatidylethanol in blood, and ethyl glucuronide and fatty acid ethyl esters in hair, among others. Moreover, there is a need to correlate the indirect biomarker carbohydrate deficient transferrin, which reflects longer lasting consumption of higher amounts of alcohol, with serum γ-glutamyl transpeptidase, another long term indirect biomarker that is routinely used and standardized in laboratory medicine. PMID:26131978
Infrared and Raman Microscopy in Cell Biology
Matthäus, Christian; Bird, Benjamin; Miljković, Miloš; Chernenko, Tatyana; Romeo, Melissa; Diem, Max
2009-01-01
This chapter presents novel microscopic methods to monitor cell biological processes of live or fixed cells without the use of any dye, stains, or other contrast agent. These methods are based on spectral techniques that detect inherent spectroscopic properties of biochemical constituents of cells, or parts thereof. Two different modalities have been developed for this task. One of them is infrared micro-spectroscopy, in which an average snapshot of a cell’s biochemical composition is collected at a spatial resolution of typically 25 mm. This technique, which is extremely sensitive and can collect such a snapshot in fractions of a second, is particularly suited for studying gross biochemical changes. The other technique, Raman microscopy (also known as Raman micro-spectroscopy), is ideally suited to study variations of cellular composition on the scale of subcellular organelles, since its spatial resolution is as good as that of fluorescence microscopy. Both techniques exhibit the fingerprint sensitivity of vibrational spectroscopy toward biochemical composition, and can be used to follow a variety of cellular processes. PMID:19118679
Study Design of the Maycoba Project: Obesity and Diabetes in Mexican Pimas
Urquidez-Romero, Rene; Esparza-Romero, Julian; Chaudhari, Lisa S.; Begay, R. Cruz; Giraldo, Mario; Ravussin, Eric; Knowler, William C.; Hanson, Robert L.; Bennett, Peter H.; Schulz, Leslie O.; Valencia, Mauro E.
2016-01-01
Objective To focus on the rationale and methods of the Maycoba Project. Methods Study population included Mexican Pima Indians (MPI) and Blancos aged ≥20-years, living in the village of Maycoba and surrounding area. Surveys in 1995 and 2010 included a medical history, biochemical and anthropometric measurements. Additionally, socioeconomic, physical activity, and dietary interviews were conducted. The 2010 study incorporated investigations on type 2 diabetes (T2D) and obesity-associated genetic alleles and human-environment changes. Results The study results are limited to demographic data and description of the eligible and examined sample. Conclusions This study may yield important information on T2D and obesity etiology in a traditional population exposed to environmental changes. PMID:24636033
2016-01-04
Biochemical Analysis of Cellulose-DegradingBacterial Communities from Sheep Rumen, Termite Hindgut, Decaying Plant Materials,and Soil In an effort to...degrading bacteria from various samples, including termite gut, sheep rumen, soil, and decaying plant materials. Using selective media culture with...Metagenomic Characterization and Biochemical Analysis of Cellulose-DegradingBacterial Communities from Sheep Rumen, Termite Hindgut, Decaying Plant
Ultralocalized thermal reactions in subnanoliter droplets-in-air.
Salm, Eric; Guevara, Carlos Duarte; Dak, Piyush; Dorvel, Brian Ross; Reddy, Bobby; Alam, Muhammad Ashraf; Bashir, Rashid
2013-02-26
Miniaturized laboratory-on-chip systems promise rapid, sensitive, and multiplexed detection of biological samples for medical diagnostics, drug discovery, and high-throughput screening. Within miniaturized laboratory-on-chips, static and dynamic droplets of fluids in different immiscible media have been used as individual vessels to perform biochemical reactions and confine the products. Approaches to perform localized heating of these individual subnanoliter droplets can allow for new applications that require parallel, time-, and space-multiplex reactions on a single integrated circuit. Our method positions droplets on an array of individual silicon microwave heaters on chip to precisely control the temperature of droplets-in-air, allowing us to perform biochemical reactions, including DNA melting and detection of single base mismatches. We also demonstrate that ssDNA probe molecules can be placed on heaters in solution, dried, and then rehydrated by ssDNA target molecules in droplets for hybridization and detection. This platform enables many applications in droplets including hybridization of low copy number DNA molecules, lysing of single cells, interrogation of ligand-receptor interactions, and rapid temperature cycling for amplification of DNA molecules.
Hierarchical thinking in network biology: the unbiased modularization of biochemical networks.
Papin, Jason A; Reed, Jennifer L; Palsson, Bernhard O
2004-12-01
As reconstructed biochemical reaction networks continue to grow in size and scope, there is a growing need to describe the functional modules within them. Such modules facilitate the study of biological processes by deconstructing complex biological networks into conceptually simple entities. The definition of network modules is often based on intuitive reasoning. As an alternative, methods are being developed for defining biochemical network modules in an unbiased fashion. These unbiased network modules are mathematically derived from the structure of the whole network under consideration.
Roche, Daniel Barry; Brackenridge, Danielle Allison; McGuffin, Liam James
2015-12-15
Elucidating the biological and biochemical roles of proteins, and subsequently determining their interacting partners, can be difficult and time consuming using in vitro and/or in vivo methods, and consequently the majority of newly sequenced proteins will have unknown structures and functions. However, in silico methods for predicting protein-ligand binding sites and protein biochemical functions offer an alternative practical solution. The characterisation of protein-ligand binding sites is essential for investigating new functional roles, which can impact the major biological research spheres of health, food, and energy security. In this review we discuss the role in silico methods play in 3D modelling of protein-ligand binding sites, along with their role in predicting biochemical functionality. In addition, we describe in detail some of the key alternative in silico prediction approaches that are available, as well as discussing the Critical Assessment of Techniques for Protein Structure Prediction (CASP) and the Continuous Automated Model EvaluatiOn (CAMEO) projects, and their impact on developments in the field. Furthermore, we discuss the importance of protein function prediction methods for tackling 21st century problems.
Reporting the accuracy of biochemical measurements for epidemiologic and nutrition studies.
McShane, L M; Clark, L C; Combs, G F; Turnbull, B W
1991-06-01
Procedures for reporting and monitoring the accuracy of biochemical measurements are presented. They are proposed as standard reporting procedures for laboratory assays for epidemiologic and clinical-nutrition studies. The recommended procedures require identification and estimation of all major sources of variability and explanations of laboratory quality control procedures employed. Variance-components techniques are used to model the total variability and calculate a maximum percent error that provides an easily understandable measure of laboratory precision accounting for all sources of variability. This avoids ambiguities encountered when reporting an SD that may taken into account only a few of the potential sources of variability. Other proposed uses of the total-variability model include estimating precision of laboratory methods for various replication schemes and developing effective quality control-checking schemes. These procedures are demonstrated with an example of the analysis of alpha-tocopherol in human plasma by using high-performance liquid chromatography.
Ryan, Gillian L; Watanabe, Naoki; Vavylonis, Dimitrios
2012-04-01
A characteristic feature of motile cells as they undergo a change in motile behavior is the development of fluctuating exploratory motions of the leading edge, driven by actin polymerization. We review quantitative models of these protrusion and retraction phenomena. Theoretical studies have been motivated by advances in experimental and computational methods that allow controlled perturbations, single molecule imaging, and analysis of spatiotemporal correlations in microscopic images. To explain oscillations and waves of the leading edge, most theoretical models propose nonlinear interactions and feedback mechanisms among different components of the actin cytoskeleton system. These mechanisms include curvature-sensing membrane proteins, myosin contraction, and autocatalytic biochemical reaction kinetics. We discuss how the combination of experimental studies with modeling promises to quantify the relative importance of these biochemical and biophysical processes at the leading edge and to evaluate their generality across cell types and extracellular environments. Copyright © 2012 Wiley Periodicals, Inc.
Thermodynamically consistent model calibration in chemical kinetics
2011-01-01
Background The dynamics of biochemical reaction systems are constrained by the fundamental laws of thermodynamics, which impose well-defined relationships among the reaction rate constants characterizing these systems. Constructing biochemical reaction systems from experimental observations often leads to parameter values that do not satisfy the necessary thermodynamic constraints. This can result in models that are not physically realizable and may lead to inaccurate, or even erroneous, descriptions of cellular function. Results We introduce a thermodynamically consistent model calibration (TCMC) method that can be effectively used to provide thermodynamically feasible values for the parameters of an open biochemical reaction system. The proposed method formulates the model calibration problem as a constrained optimization problem that takes thermodynamic constraints (and, if desired, additional non-thermodynamic constraints) into account. By calculating thermodynamically feasible values for the kinetic parameters of a well-known model of the EGF/ERK signaling cascade, we demonstrate the qualitative and quantitative significance of imposing thermodynamic constraints on these parameters and the effectiveness of our method for accomplishing this important task. MATLAB software, using the Systems Biology Toolbox 2.1, can be accessed from http://www.cis.jhu.edu/~goutsias/CSS lab/software.html. An SBML file containing the thermodynamically feasible EGF/ERK signaling cascade model can be found in the BioModels database. Conclusions TCMC is a simple and flexible method for obtaining physically plausible values for the kinetic parameters of open biochemical reaction systems. It can be effectively used to recalculate a thermodynamically consistent set of parameter values for existing thermodynamically infeasible biochemical reaction models of cellular function as well as to estimate thermodynamically feasible values for the parameters of new models. Furthermore, TCMC can provide dimensionality reduction, better estimation performance, and lower computational complexity, and can help to alleviate the problem of data overfitting. PMID:21548948
Problems in aerial application. I, Some biochemical effects of lindane and dieldrin on vertebrates.
DOT National Transportation Integrated Search
1962-05-01
Chronic exposure to the chlorinated hydrocarbon, lindane, elicited alterations in several biochemical values of rat tissues. These included ribonucleic acid quantities, water content, and the cytochrome oxidase activity of heart sarcosomes. The chlor...
A technique is presented for finding the least squares estimates for the ultimate biochemical oxygen demand (BOD) and rate coefficient for the BOD reaction without resorting to complicated computer algorithms or subjective graphical methods. This may be used in stream water quali...
[A study of biomechanical method for urine test based on color difference estimation].
Wang, Chunhong; Zhou, Yue; Zhao, Hongxia; Zhou, Fengkun
2008-02-01
The biochemical analysis of urine is an important inspection and diagnosis method in hospitals. The conventional method of urine analysis covers mainly colorimetric visual appraisement and automation detection, in which the colorimetric visual appraisement technique has been superseded basically, and the automation detection method is adopted in hospital; moreover, the price of urine biochemical analyzer on market is around twenty thousand RMB yuan (Y), which is hard to enter into ordinary families. It is known that computer vision system is not subject to the physiological and psychological influence of person, its appraisement standard is objective and steady. Therefore, according to the color theory, we have established a computer vision system, which can carry through collection, management, display, and appraisement of color difference between the color of standard threshold value and the color of urine test paper after reaction with urine liquid, and then the level of an illness can be judged accurately. In this paper, we introduce the Urine Test Biochemical Analysis method, which is new and can be popularized in families. Experimental result shows that this test method is easy-to-use and cost-effective. It can realize the monitoring of a whole course and can find extensive applications.
NASA Technical Reports Server (NTRS)
Dorchak, K. J.; Greenleaf, J. E.
1976-01-01
Major studies that describe the physiological and biochemical mechanisms which operate during total body restraint (confinement in cages for example) are presented. The metabolism and behavior of various animals used in medical research (dogs, monkeys, rats, fowl) was investigated and wherever possible a detailed annotation for each study is provided under the subheadings: (a) purposes, (b) procedures and methods, (c) results, and (d) conclusions. Selected references are also included.
The Investigation of Serum Vaspin Level in Atherosclerotic Coronary Artery Disease
Kobat, Mehmet Ali; Celik, Ahmet; Balin, Mehmet; Altas, Yakup; Baydas, Adil; Bulut, Musa; Aydin, Suleyman; Dagli, Necati; Yavuzkir, Mustafa Ferzeyn; Ilhan, Selcuk
2012-01-01
Background It was speculated that fatty tissue originated adipocytokines may play role in pathogenesis of atherosclerosis. These adipocytokines may alter vascular homeostasis by effecting endothelial cells, arterial smooth muscle cells and macrophages. Vaspin is a newly described member of adipocytokines family. We aimed to investigate whether plasma vaspin level has any predictive value in coronary artery disease (CAD). Methods Forty patients who have at least single vessel ≥ 70 % stenosis demostrated angiographically and 40 subjects with normal coronary anatomy were included to the study. The vaspin levels were measured from serum that is obtained by centrifigation of blood and stored at -20 oC by ELISA method. The length, weight and body mass index of patients were measured. Biochemical parameters including total cholesterol, low density lipoprotein, high density lipoprotein, creatinine, sodium, potassium, hemoglobine, uric acid and fasting glucose were also measured. Results Biochemical markers levels were similar in both groups. Serum vaspin levels were significantly lower in CAD patients than control group (respectively; 256 ± 219 pg/ml vs. 472 ( 564 pg/ml, P < 0.02). Beside this serum vaspin level was lower in control group with high systolic blood pressure. Conclusion Serum vaspin levels were found significantly lower in patients with CAD than age-matched subjects with normal coronary anatomy. Vaspin may be used as a predictor of CAD. Keywords Coronary artery disease; Vaspin; Adipokine PMID:22505983
Detection and Identification of Salmonella spp. in Surface Water by Molecular Technology in Taiwan
NASA Astrophysics Data System (ADS)
Tseng, S. F.; Hsu, B. M.; Huang, K. H.; Hsiao, H. Y.; Kao, P. M.; Shen, S. M.; Tsai, H. F.; Chen, J. S.
2012-04-01
Salmonella spp. is classified to gram-negative bacterium and is one of the most important causal agents of waterborne diseases. The genus of Salmonella comprises more than 2,500 serotypes and its taxonomy is also very complicated. In tradition, the detection of Salmonella in environmental water samples by routines culture methods using selective media and characterization of suspicious colonies based on biochemical tests and serological assay are generally time and labor consuming. To overcome this disadvantage, it is desirable to use effective method which provides a higher discrimination and more rapid identification about Salmonella in environmental water. The aim of this study is to investigate the occurrence of Salmonella using novel procedures of detection method and to identify the serovars of Salmonella isolates from 157 surface water samples in Taiwan. The procedures include membrane filtration, non-selective pre-enrichment, selective enrichment of Salmonella, and then isolation of Salmonella strains by selective culture plates. The selective enrichment and culture plates were both detected by PCR. Finally, we used biochemical tests and serological assay to confirm the serovars of Salmonella and also used Pulsed-field gel electrophoresis (PFGE) to identify their sarovar catagories by the genetic pattern. In this study, 44 water samples (28%) were indentified as Salmonella. The 44 positive water samples by culture method were further identified as S. Agona(1/44), S. Albany (10/44), S. Bareilly (13/44),S. Choleraesuis (2/44),S. Derby (4/44),S. Isangi (3/44),S.Kedougou(3/44),S. Mbandaka(1/44),S.Newport (3/44), S. Oranienburg(1/44), S. Potsdam (1/44),S. Typhimurium (1/44), andS. Weltevreden(1/44) by PFGE. The presence of Salmonella in surface water indicates the possibility of waterborne transmission in drinking watershed if water is not adequately treated. Therefore, the authorities need to have operating systems that currently provide adequate source protection and maintaining the system to prevent disease. Keywords: Salmonella spp.; biochemical tests; Serological assay; PCR; PFGE
In silico characterization of microbial electrosynthesis for metabolic engineering of biochemicals
2011-01-01
Background A critical concern in metabolic engineering is the need to balance the demand and supply of redox intermediates such as NADH. Bioelectrochemical techniques offer a novel and promising method to alleviate redox imbalances during the synthesis of biochemicals and biofuels. Broadly, these techniques reduce intracellular NAD+ to NADH and therefore manipulate the cell's redox balance. The cellular response to such redox changes and the additional reducing power available to the cell can be harnessed to produce desired metabolites. In the context of microbial fermentation, these bioelectrochemical techniques can be used to improve product yields and/or productivity. Results We have developed a method to characterize the role of bioelectrosynthesis in chemical production using the genome-scale metabolic model of E. coli. The results in this paper elucidate the role of bioelectrosynthesis and its impact on biomass growth, cellular ATP yields and biochemical production. The results also suggest that strain design strategies can change for fermentation processes that employ microbial electrosynthesis and suggest that dynamic operating strategies lead to maximizing productivity. Conclusions The results in this paper provide a systematic understanding of the benefits and limitations of bioelectrochemical techniques for biochemical production and highlight how electrical enhancement can impact cellular metabolism and biochemical production. PMID:21967745
Reconstructing biochemical pathways from time course data.
Srividhya, Jeyaraman; Crampin, Edmund J; McSharry, Patrick E; Schnell, Santiago
2007-03-01
Time series data on biochemical reactions reveal transient behavior, away from chemical equilibrium, and contain information on the dynamic interactions among reacting components. However, this information can be difficult to extract using conventional analysis techniques. We present a new method to infer biochemical pathway mechanisms from time course data using a global nonlinear modeling technique to identify the elementary reaction steps which constitute the pathway. The method involves the generation of a complete dictionary of polynomial basis functions based on the law of mass action. Using these basis functions, there are two approaches to model construction, namely the general to specific and the specific to general approach. We demonstrate that our new methodology reconstructs the chemical reaction steps and connectivity of the glycolytic pathway of Lactococcus lactis from time course experimental data.
Tabashsum, Zajeba; Nazneen, Mafruha; Ahsan, C R; Bari, M L; Yasmin, M
2016-01-01
Presence of Escherichia coli O157:H7 on fresh goat meat samples (n= 40) of Dhaka city was analyzed using conventional and molecular methods. A total of 86 presumptive E. coli O157:H7 colonies were isolated from 60% of the samples using selective agar plating method. After conventional biochemical assay followed by API 20E assay, only 11 isolates were found to be E. coli O157:H7. Further serological test identified only four isolates that has strong agglutination reaction against anti-H7 sensitized latex. The biochemically and serologically confirmed isolates were then screened for major virulence factors include eaeA, rfbE, fliC, stx1 and stx2 genes by PCR. PCR analysis of positive isolates showed, 10 isolates were eaeA and rfbE genes positive but fliC gene was only in six, indicating that these isolates were H7 positive with flagellum antigens which might not expressed or detected in serotyping tests. Multiplex PCR against eaeA, stx1 and stx2 genes of the isolates showed similar results as when done individually. These results revealed that only 7% of the primary presumptive E. coli O157:H7 was found to be stx producing E. coli O157:H7 and thus greatly influenced the detection of the pathogen in meat samples.
Schlussel Markovic, Emily; Buckstein, Michael; Stone, Nelson N; Stock, Richard G
2018-05-01
To evaluate the cancer control outcomes and long-term treatment-related morbidity of brachytherapy as well as combination brachytherapy and external beam radiation therapy (EBRT) in patients with intermediate-risk prostate cancer. A retrospective review was conducted in a prospectively collected database of patients with intermediate-risk prostate cancer who were treated either with brachytherapy or brachytherapy and EBRT, with or without androgen deprivation therapy (ADT), in the period 1990-2014. Urinary and erectile dysfunction symptoms were measured using the International Prostate Symptom Score (IPSS), the Mount Sinai erectile function scale and the Sexual Health Inventory for Men (SHIM). Cancer control endpoints included biochemical failure and development of distant metastases. All statistical analyses were carried out using the Statistical Package for Social Science (SPSS). Survival curves were calculated using Kaplan-Meier actuarial methods and compared using log-rank tests. Cox regression multivariate analyses were used to test the effect of multiple variables on treatment outcomes. A total of 902 patients were identified, with a median follow-up of 91 months. Of these, 390 received brachytherapy and 512 received combination therapy with EBRT. In patients with one intermediate-risk factor, the addition of EBRT did not significantly affect freedom from biochemical failure or distant metastases. Among patients with two or three intermediate-risk factors, added EBRT did not improve freedom from biochemical failure. Significant differences in late toxicity between patients treated with brachytherapy vs combination brachytherapy and EBRT were identified including urge incontinence (P < 0.001), haematuria (P < 0.001), dysuria (P < 0.001), and change in quality-of-life IPSS (P = 0.002). These symptoms were reported by patients at any point during treatment follow-up. Analysis of patients who were potent before treatment using actuarial methods showed that patients receiving combination therapy more frequently experienced loss of potency, as measured by the Mount Sinai erectile function scale (P = 0.040). Brachytherapy monotherapy results in equal biochemical and distant control in both patients with one and more than one intermediate-risk features. While no significant benefit was shown, we believe that the addition of EBRT may prevent recurrence in patients with multiple intermediate-risk features and should be considered. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.
Biochemical simulations: stochastic, approximate stochastic and hybrid approaches.
Pahle, Jürgen
2009-01-01
Computer simulations have become an invaluable tool to study the sometimes counterintuitive temporal dynamics of (bio-)chemical systems. In particular, stochastic simulation methods have attracted increasing interest recently. In contrast to the well-known deterministic approach based on ordinary differential equations, they can capture effects that occur due to the underlying discreteness of the systems and random fluctuations in molecular numbers. Numerous stochastic, approximate stochastic and hybrid simulation methods have been proposed in the literature. In this article, they are systematically reviewed in order to guide the researcher and help her find the appropriate method for a specific problem.
Biochemical simulations: stochastic, approximate stochastic and hybrid approaches
2009-01-01
Computer simulations have become an invaluable tool to study the sometimes counterintuitive temporal dynamics of (bio-)chemical systems. In particular, stochastic simulation methods have attracted increasing interest recently. In contrast to the well-known deterministic approach based on ordinary differential equations, they can capture effects that occur due to the underlying discreteness of the systems and random fluctuations in molecular numbers. Numerous stochastic, approximate stochastic and hybrid simulation methods have been proposed in the literature. In this article, they are systematically reviewed in order to guide the researcher and help her find the appropriate method for a specific problem. PMID:19151097
Advanced Nanoporous Materials for Micro-Gravimetric Sensing to Trace-Level Bio/Chemical Molecules
Xu, Pengcheng; Li, Xinxin; Yu, Haitao; Xu, Tiegang
2014-01-01
Functionalized nanoporous materials have been developed recently as bio/chemical sensing materials. Due to the huge specific surface of the nano-materials for molecular adsorption, high hopes have been placed on gravimetric detection with micro/nano resonant cantilevers for ultra-sensitive sensing of low-concentration bio/chemical substances. In order to enhance selectivity of the gravimetric resonant sensors to the target molecules, it is crucial to modify specific groups onto the pore-surface of the nano-materials. By loading the nanoporous sensing material onto the desired region of the mass-type transducers like resonant cantilevers, the micro-gravimetric bio/chemical sensors can be formed. Recently, such micro-gravimetric bio/chemical sensors have been successfully applied for rapid or on-the-spot detection of various bio/chemical molecules at the trace-concentration level. The applicable nanoporous sensing materials include mesoporous silica, zeolite, nanoporous graphene oxide (GO) and so on. This review article focuses on the recent achievements in design, preparation, functionalization and characterization of advanced nanoporous sensing materials for micro-gravimetric bio/chemical sensing. PMID:25313499
de Assumpção, Priscila Kurz; Heinzmann-Filho, João Paulo; Isaia, Heloisa Ataíde; Holzschuh, Flávia; Dalcul, Tiéle; Donadio, Márcio Vinícius Fagundes
2018-03-23
To evaluate exercise capacity of obese children and adolescents compared with normal-weight individuals and to investigate possible correlations with blood biochemical parameters. In this study, children and adolescents between 6 and 18 y were included and divided into control (eutrophic) and obese groups according to body mass index (BMI). Data were collected regarding demographic, anthropometric, waist circumference and exercise capacity through the Modified Shuttle Walk Test (MSWT). In the obese group, biochemical parameters in the blood (total cholesterol, HDL, LDL, triglycerides and glucose) were evaluated, and a physical activity questionnaire was applied. Seventy seven participants were included; 27 in the control group and 50 obese. There was no significant difference between the two groups regarding sample characteristics, except for body weight, BMI and waist circumference. Most obese children presented results of biochemical tests within the desirable limit, though none were considered active. There was a significant exercise capacity reduction (p < 0.001) in the obese group compared to control subjects. Positive correlations were identified for the MSWT with age and height, and a negative correlation with BMI. However, there were no correlations with the biochemical parameters analyzed. Obese children and adolescents have reduced exercise capacity when compared to normal individuals. The MSWT performance seems to have a negative association with BMI, but is not correlated with blood biochemical parameters.
Meamar, Rokhsareh; Maracy, Mohammad; Nematollahi, Shahrzad; Yeroshalmi, Shemouil; Zamani-Moghaddam, Ali; Ghazvini, Mohammad Reza Aghaye
2015-01-01
Background: The improved physical action following administration of supplements to bodybuilders was supported by changes in laboratory parameters. Despite the fact that these supplements are sometimes associated both advantage and side effects, this study were conducted for the purpose of evaluating the possible effects of some commonly used supplements in bodybuilders on the hematological and biochemical parameters. Materials and Methods: In this study, we included 40 male bodybuilders as cases and 40 controls in the age group of 20-40 years. They used different kinds of supplements for 1 year. In general, all the supplements used were classified into two groups: hormonal and non-hormonal. Laboratory tests were requested for evaluation of hematological and biochemical parameters. Results: In an equation model, we found that weight (P = 0.024), duration of bodybuilding (P < 0.001), and duration of hormone supplement consumption (P < 0.001) were loaded significantly on the latent variables, demographic and dietary supplement, respectively. The relationship between dietary supplement and biochemical and hematological parameters was significant (P = 0.01) and some of these parameters including creatinine (P = 0.023), blood aspartate aminotransferase (AST) (P < 0.001), alanine aminotransferase (ALT) (P < 0.001), and red blood cell distribution (RDW) (P = 0.046) had a significant role than others. In a multivariate regression model, we found that WBC (P < 0.001), platelets (P < 0.001), blood urea nitrogen (BUN; P < 0.001), creatinine (P < 0.001), AST (P = 0.005), and ALT (P = 0.001) were higher in athletes than in controls. Conclusions: It is strongly advised that there should be some concerns about possible supplement-induced changes in the laboratory exams for bodybuilders. The available supplements are unchecked and not approved by the US Food and Drug Administration (FDA). More studies should be designed for a better and precise administration of each supplement in athletes. PMID:26793253
Histochemical identification of malignant and premalignant lesions
NASA Astrophysics Data System (ADS)
Liebow, Charles; Maloney, M. J.
1991-06-01
Malignant and transforming cells can be identified by biochemical parameters which can be used to localize lesions in situ for laser surgery. These cells express unique proteins, proteins in unusual quantities, or other biochemical alterations which can be utilized to image lesions of such cells. Several methods have been identified, both in vitro and in vivo, to identify such lesions. Several antibodies were examined for their properties of tissue identification, including CEA, F36/22, and AE1/AE3. F36/22, an antibody developed by M. T. Chu against human breast cancer cells, associated with two lines of oral cancer (KB and HCPC), and against two naturally occurring human oral squamous cell cancers. CEA, an antibody developed against human colon cancer, also reacted against both cell lines and both pathological samples. AE1/AE3, developed against normal fibrous components, also reacted against the samples, but in a much less regular manner. F36/22 associated with the histologically identifiably most dedifferentiated cells at the leading edge of the invading cancer. CEA, on the other hand, associated with more quiescent, older, established cancer cells. This demonstrates that antibodies developed against cancers of different organs can be used to identify a wide variety of cancers, and may have prognostic value. F36/22 coupled to fluorescein was used to identify oral cancer cells. Other properties of cancers and developing cancers can also be exploited to identify cancers, including their over-expression of tyrosine kinase and tyrosine kinase stimulating hormones such as Epidermal Growth Factor (EGF). A model of premalignant lesion produced in the hamster buccal cheek pouch with 6 week application of DMBA over-expresses constitutive tyrosine kinase which can be demonstrated biochemically. This initiated lesion can be promoted to frank cancer by growth factors released in response to laser surgery. Preliminary results suggest that these lesions can be identified by Photofrin II uptake. This work suggests that biochemical properties of cancers can be used to identify premalignant cells.
Wang, Qilin; Sun, Jing; Zhang, Chang; Xie, Guo-Jun; Zhou, Xu; Qian, Jin; Yang, Guojing; Zeng, Guangming; Liu, Yiqi; Wang, Dongbo
2016-01-21
Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d(-1)) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery.
Wang, Qilin; Sun, Jing; Zhang, Chang; Xie, Guo-Jun; Zhou, Xu; Qian, Jin; Yang, Guojing; Zeng, Guangming; Liu, Yiqi; Wang, Dongbo
2016-01-01
Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d−1) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery. PMID:26791952
NASA Astrophysics Data System (ADS)
Wang, Qilin; Sun, Jing; Zhang, Chang; Xie, Guo-Jun; Zhou, Xu; Qian, Jin; Yang, Guojing; Zeng, Guangming; Liu, Yiqi; Wang, Dongbo
2016-01-01
Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d-1) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery.
Anaerobic biochemical reactors (BCRs) are useful for removing metals from mining-impacted water at remote sites. Removal processes include sorption and precipitation of metal sulfides, carbonates, and hydroxides. A question of interest is whether BCRs remove aquatic toxicity. ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boyer, G.L.; Speirs, R.J.; Morse, P.D.
1990-06-01
Iron is essential for the growth of living cells. To meet biochemical needs, microorganisms, including algae, produce high affinity chelators termed siderophores. These compounds solubilize Fe and increase its bioavailability. We have developed a new method to study siderophore formation in cultured and natural environments. Based on the fact siderophores tightly bind 55-Fe, the radioactive complexes can be separated by HPLC using an inert PRP-1 column and detected by scintillation counting. This method cleanly resolves several known siderophores, including ferrichrome A, ferrichrome, desferal, and rhodotorulic acid. The optimization of the method and its use for analysis of siderophore formation inmore » bacteria (E. coli, and Bacillus megaterium), fungi (Ustilago sphaerogena), and cyanobacteria (Anabaena flos-aqua UTEX 1444 and Anabaena sp. ATCC 27898) will be presented.« less
NASA Astrophysics Data System (ADS)
Günter, Tuğçe; Alpat, Sibel Kılınç
2017-11-01
The purpose of this study was to investigate the effect of the case-based learning (CBL) method used in "biochemical oxygen demand (BOD)," which is a topic taught in the environmental chemistry course, at Dokuz Eylul University, on the academic achievement and opinions of students. The research had a quasi-experimental design and the study group consisted of 4th and 5th grade students (N = 18) attending the Chemistry Teaching Program in a university in Izmir. The "Biochemical Oxygen Demand Achievement Test (BODAT)" and the structured interview form were used as data collection tools. The results of BODAT post-test showed the higher increase in the achievement scores of the experimental group may be an indication of the effectiveness of the CBL method in improving academic achievement in the relevant topic. In addition, the experimental and control group students had positive opinions regarding the method, the scenario, and the material. The students found the method, the scenario, and the material to be interesting, understandable/instructional, relatable with everyday life, suitable for the topic, and enhancing active participation.
Biochemical and Structural Studies of RNA Modification and Repair
ERIC Educational Resources Information Center
Chan, Chio Mui
2009-01-01
RNA modification, RNA interference, and RNA repair are important events in the cell. This thesis presents three projects related to these three fields. By using both biochemical and structural methods, we characterized enzymatic activities of pseudouridine synthase TruD, solved the structure of "A. aeolicus" GidA, and reconstituted a novel…
Biochemical profiling in silico--predicting substrate specificities of large enzyme families.
Tyagi, Sadhna; Pleiss, Juergen
2006-06-25
A general high-throughput method for in silico biochemical profiling of enzyme families has been developed based on covalent docking of potential substrates into the binding sites of target enzymes. The method has been tested by systematically docking transition state--analogous intermediates of 12 substrates into the binding sites of 20 alpha/beta hydrolases from 15 homologous families. To evaluate the effect of side chain orientations to the docking results, 137 crystal structures were included in the analysis. A good substrate must fulfil two criteria: it must bind in a productive geometry with four hydrogen bonds between the substrate and the catalytic histidine and the oxyanion hole, and a high affinity of the enzyme-substrate complex as predicted by a high docking score. The modelling results in general reproduce experimental data on substrate specificity and stereoselectivity: the differences in substrate specificity of cholinesterases toward acetyl- and butyrylcholine, the changes of activity of lipases and esterases upon the size of the acid moieties, activity of lipases and esterases toward tertiary alcohols, and the stereopreference of lipases and esterases toward chiral secondary alcohols. Rigidity of the docking procedure was the major reason for false positive and false negative predictions, as the geometry of the complex and docking score may sensitively depend on the orientation of individual side chains. Therefore, appropriate structures have to be identified. In silico biochemical profiling provides a time efficient and cost saving protocol for virtual screening to identify the potential substrates of the members of large enzyme family from a library of molecules.
Caine, Sally; Heraud, Philip; Tobin, Mark J; McNaughton, Donald; Bernard, Claude C A
2012-02-15
In the last two decades the field of infrared spectroscopy has seen enormous advances in both instrumentation and the development of bioinformatic methods for spectral analysis, allowing the examination of a large variety of healthy and diseased samples, including biological fluids, isolated cells, whole tissues, and tissue sections. The non-destructive nature of the technique, together with the ability to directly probe biochemical changes without the addition of stains or contrast agents, enables a range of complementary analyses. This review focuses on the application of Fourier transform infrared (FTIR) microspectroscopy to analyse central nervous system tissues, with the aim of understanding the biochemical and structural changes associated with neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, transmissible spongiform encephalopathies, multiple sclerosis, as well as brain tumours. Modern biospectroscopic methods that combine FTIR microspectroscopy with bioinformatic analysis constitute a powerful new methodology that can discriminate pathology from normal healthy tissue in a rapid, unbiased fashion, with high sensitivity and specificity. Notably, the ability to detect protein secondary structural changes associated with Alzheimer's plaques, neurons in Parkinson's disease, and in some spectra from meningioma, as well as in the animal models of Alzheimer's disease, transmissible spongiform encephalopathies, and multiple sclerosis, illustrates the power of this technology. The capacity to offer insight into the biochemical and structural changes underpinning aetio-pathogenesis of diseases in tissues provides both a platform to investigate early pathologies occurring in a variety of experimentally induced and naturally occurring central nervous system diseases, and the potential to evaluate new therapeutic approaches. Copyright © 2011 Elsevier Inc. All rights reserved.
Proton magnetic resonance spectroscopy imaging in the study of human brain cancer.
Martínez-Bisbal, M C; Celda, B
2009-12-01
Magnetic resonance spectroscopic imaging (MRSI) is a non-invasive imaging technique that provides metabolic information on brain tumor. This biochemical information can be processed and presented as density maps of several metabolites, among them N-acetylaspartate (marker of neuronal viability), choline (marker of membrane turnover), creatine (related to the energy state of the cells), myo-Inositol (exclusively found in astrocytes), lipids and lactate (observed in necrosis and other pathological processes) which mean relevant information in the context of brain tumors. Thus, this technique is a multiparametrical molecular imaging method that can complete the magnetic resonance imaging (MRI) study enabling the detection of biochemical patterns of different features and aspects of brain tumors. In this article, the role of MRSI as a molecular imaging technique to provide biochemical information on human brain tumors is reviewed. The most frequent questions and situations in the study of human brain tumors in clinical settings will be considered, as well as the distinction of neoplastic lesions from non neoplastic, the tumor type identification, the study of heterogeneity and infiltration of normal appearing white matter and the therapy following with detection of side effects. The great amount of data in MRSI acquisition compared to the single voxel techniques requires the use of automated methods of quantification, but the possibility to obtain self-reference in the non-affected areas allows different strategies for data handling and interpretation, as presented in the literature. The combination of MRSI with other physiological MRI techniques and positron emission tomography is also included in this review.
Martinez-Vaz, Betsy M; Denny, Roxanne; Young, Nevin D; Sadowsky, Michael J
2015-12-01
Microbiology courses often include a laboratory activity on the identification of unknown microbes. This activity consists of providing students with microbial cultures and running biochemical assays to identify the organisms. This approach lacks molecular techniques such as sequencing of genes encoding 16S rRNA, which is currently the method of choice for identification of unknown bacteria. A laboratory activity was developed to teach students how to identify microorganisms using 16S rRNA polymerase chain reaction (PCR) and validate microbial identities using biochemical techniques. We hypothesized that designing an experimental protocol to confirm the identity of a bacterium would improve students' knowledge of microbial identification techniques and the physiological characteristics of bacterial species. Nitrogen-fixing bacteria were isolated from the root nodules of Medicago truncatula and prepared for 16S rRNA PCR analysis. Once DNA sequencing revealed the identity of the organisms, the students designed experimental protocols to verify the identity of rhizobia. An assessment was conducted by analyzing pre- and posttest scores and by grading students' verification protocols and presentations. Posttest scores were higher than pretest scores at or below p = 0.001. Normalized learning gains (G) showed an improvement of students' knowledge of microbial identification methods (LO4, G = 0.46), biochemical properties of nitrogen-fixing bacteria (LO3, G = 0.45), and the events leading to the establishment of nitrogen-fixing symbioses (LO1&2, G = 0.51, G = 0.37). An evaluation of verification protocols also showed significant improvement with a p value of less than 0.001.
Birk, Ruth; Heifetz, Eliyahu M
2018-04-28
Biochemical laboratory values are an essential tool in medical diagnosis, treatment, and follow-up; however, they are known to vary between populations. Establishment of ethnicity-adjusted reference values is recommended by health organizations. To investigate the ethnicity element in biochemical lab values studying women of different ethnic groups. Biochemical lab values (n = 27) of 503 adult Israeli women of three ethnicities (Jewish Ashkenazi, Jewish Sephardic, and Bedouin Arab) attending a single medical center were analyzed. Biochemical data were extracted from medical center records. Ethnic differences of laboratory biochemicals were studied using ANCOVA to analyze the center of the distribution as well as quartile regression analysis to analyze the upper and lower limits, both done with an adjustment for age. Significant ethnic differences were found in almost half (n = 12) of the biochemical laboratory tests. Ashkenazi Jews exhibited significantly higher mean values compared to Bedouins in most of the biochemical tests, including albumin, alkaline phosphatase, calcium, cholesterol, cholesterol LDL and HDL, cholesterol LDL calc., folic acid, globulin, and iron saturation, while the Bedouins exhibited the highest mean values in the creatinine and triglycerides. For most of these tests, Sephardic Jews exhibited biochemical mean levels in between the two other groups. Compared to Ashkenazi Jews, Sephardic Jews had a significant shift to lower values in cholesterol LDL. Ethnic subpopulations have distinct distributions in biochemical laboratory test values, which should be taken into consideration in medical practice enabling precision medicine.
Age-dependent biochemical quantities: an approach for calculating reference intervals.
Bjerner, J
2007-01-01
A parametric method is often preferred when calculating reference intervals for biochemical quantities, as non-parametric methods are less efficient and require more observations/study subjects. Parametric methods are complicated, however, because of three commonly encountered features. First, biochemical quantities seldom display a Gaussian distribution, and there must either be a transformation procedure to obtain such a distribution or a more complex distribution has to be used. Second, biochemical quantities are often dependent on a continuous covariate, exemplified by rising serum concentrations of MUC1 (episialin, CA15.3) with increasing age. Third, outliers often exert substantial influence on parametric estimations and therefore need to be excluded before calculations are made. The International Federation of Clinical Chemistry (IFCC) currently recommends that confidence intervals be calculated for the reference centiles obtained. However, common statistical packages allowing for the adjustment of a continuous covariate do not make this calculation. In the method described in the current study, Tukey's fence is used to eliminate outliers and two-stage transformations (modulus-exponential-normal) in order to render Gaussian distributions. Fractional polynomials are employed to model functions for mean and standard deviations dependent on a covariate, and the model is selected by maximum likelihood. Confidence intervals are calculated for the fitted centiles by combining parameter estimation and sampling uncertainties. Finally, the elimination of outliers was made dependent on covariates by reiteration. Though a good knowledge of statistical theory is needed when performing the analysis, the current method is rewarding because the results are of practical use in patient care.
Cozzolino, D.; Degner, S.; Eglinton, J.
2014-01-01
Starch is the major component of cereal grains and starchy foods, and changes in its biophysical and biochemical properties (e.g., amylose, amylopectin, pasting, gelatinization, viscosity) will have a direct effect on its end use properties (e.g., bread, malt, polymers). The use of rapid and non-destructive methods to study and monitor starch properties, such as gelatinization, retrogradation, water absorption in cereals and starchy foods, is of great interest in order to improve and assess their quality. In recent years, near infrared reflectance (NIR) and mid infrared (MIR) spectroscopy have been explored to predict several quality parameters, such as those generated by instrumental methods commonly used in routine analysis like the rapid visco analyser (RVA) or viscometers. In this review, applications of both NIR and MIR spectroscopy to measure and monitor starch biochemical (amylose, amylopectin, starch) and biophysical properties (e.g., pasting properties) will be presented and discussed. PMID:28234340
T1ρ MR Imaging of Human Musculoskeletal System
Wang, Ligong; Regatte, Ravinder R.
2014-01-01
Magnetic resonance imaging (MRI) offers the direct visualization of human musculoskeletal (MSK) system, especially all diarthrodial tissues including cartilage, bone, menisci, ligaments, tendon, hip, synovium etc. Conventional MR imaging techniques based on T1- and T2-weighted, proton density (PD) contrast are inconclusive in quantifying early biochemically degenerative changes in MSK system in general and articular cartilage in particular. In recent years, quantitative MR parameter mapping techniques have been used to quantify the biochemical changes in articular cartilage with a special emphasis on evaluating joint injury, cartilage degeneration, and soft tissue repair. In this article, we will focus on cartilage biochemical composition, basic principles of T1ρ MR imaging, implementation of T1ρ pulse sequences, biochemical validation, and summarize the potential applications of T1ρ MR imaging technique in MSK diseases including osteoarthritis (OA), anterior cruciate ligament (ACL) injury, and knee joint repair. Finally, we will also review the potential advantages, challenges, and future prospects of T1ρ MR imaging for widespread clinical translation. PMID:24935818
T₁ρ MRI of human musculoskeletal system.
Wang, Ligong; Regatte, Ravinder R
2015-03-01
Magnetic resonance imaging (MRI) offers the direct visualization of the human musculoskeletal (MSK) system, especially all diarthrodial tissues including cartilage, bone, menisci, ligaments, tendon, hip, synovium, etc. Conventional MRI techniques based on T1 - and T2 -weighted, proton density (PD) contrast are inconclusive in quantifying early biochemically degenerative changes in MSK system in general and articular cartilage in particular. In recent years, quantitative MR parameter mapping techniques have been used to quantify the biochemical changes in articular cartilage, with a special emphasis on evaluating joint injury, cartilage degeneration, and soft tissue repair. In this article we focus on cartilage biochemical composition, basic principles of T1ρ MRI, implementation of T1ρ pulse sequences, biochemical validation, and summarize the potential applications of the T1ρ MRI technique in MSK diseases including osteoarthritis (OA), anterior cruciate ligament (ACL) injury, and knee joint repair. Finally, we also review the potential advantages, challenges, and future prospects of T1ρ MRI for widespread clinical translation. © 2014 Wiley Periodicals, Inc.
Designing degradable hydrogels for orthogonal control of cell microenvironments
Kharkar, Prathamesh M.
2013-01-01
Degradable and cell-compatible hydrogels can be designed to mimic the physical and biochemical characteristics of native extracellular matrices and provide tunability of degradation rates and related properties under physiological conditions. Hence, such hydrogels are finding widespread application in many bioengineering fields, including controlled bioactive molecule delivery, cell encapsulation for controlled three-dimensional culture, and tissue engineering. Cellular processes, such as adhesion, proliferation, spreading, migration, and differentiation, can be controlled within degradable, cell-compatible hydrogels with temporal tuning of biochemical or biophysical cues, such as growth factor presentation or hydrogel stiffness. However, thoughtful selection of hydrogel base materials, formation chemistries, and degradable moieties is necessary to achieve the appropriate level of property control and desired cellular response. In this review, hydrogel design considerations and materials for hydrogel preparation, ranging from natural polymers to synthetic polymers, are overviewed. Recent advances in chemical and physical methods to crosslink hydrogels are highlighted, as well as recent developments in controlling hydrogel degradation rates and modes of degradation. Special attention is given to spatial or temporal presentation of various biochemical and biophysical cues to modulate cell response in static (i.e., non-degradable) or dynamic (i.e., degradable) microenvironments. This review provides insight into the design of new cell-compatible, degradable hydrogels to understand and modulate cellular processes for various biomedical applications. PMID:23609001
Topić, E; Turek, S
2000-01-01
The basic criterion for the overall quality system in medical biochemistry laboratories concerning equipment, premises and laboratory staff in primary health care (PHC) (Regulations on quality systems and good laboratory practice of the Croatian Medical Biochemists Chamber, 1995, Regulations on categorization of medical biochemistry laboratories of the Croatian Medical Biochemists Chamber, 1996, EC4: Essential criteria for quality systems in medical laboratories. Eur J Clin Chem Clin Biochem 1997 in medical biochemical laboratories included in the First Croatia health project, Primary health care subproject, has been met by the marketing approach to the project. The equipment ensuring implementation of the complete laboratory program (NN/96), more accurate and precise analytical procedures, and higher reliability of laboratory test results compared with previous equipment, has been purchased by an international tender. Uniform technology and methods of analysis have ensured high standards of good laboratory services, yielding test results than can be transferred from primary to secondary health care level. The new equipment has improved organization between central and detached medical biochemistry laboratory units, while the high quality requirement has led to improvement in the staff structure, e.g., medical biochemists have been employed in laboratories that had previously worked without such a professional. Equipment renewal has been accompanied by proper education for all levels of PHC professionals.
Khorsandi, Hassan; Alizadeh, Rahimeh; Tosinejad, Horiyeh; Porghaffar, Hadi
2014-01-01
In this descriptive-analytical study, nitrogenous and algal oxygen demand were assessed for effluent from a system of facultative partially mixed lagoons followed by the polishing pond using 120 grab samples over 1 year. Filtered and non-filtered samples of polishing pond effluent were tested in the presence and absence of a nitrification inhibitor. Effective factors, including 5-day biochemical and chemical oxygen demand (BOD and COD), total suspended solids (TSS), dissolved oxygen, chlorophyll A, and temperature, were measured using standard methods for water and wastewater tests. The results were analyzed using repeated measures analysis of variance with SPSS version 16. Findings show that the annual mean of the total 5-day BOD in the effluent from the polishing pond consisted of 44.92% as the algal carbonaceous biochemical oxygen demand (CBOD), 43.61% as the nitrogenous biochemical oxygen demand (NBOD), and 11.47% as the soluble CBOD. According to this study, the annual mean ratios of algal COD and 5-day algal CBOD to TSS were 0.8 and 0.37, respectively. As the results demonstrate, undertaking quality evaluation of the final effluent from the lagoons without considering nitrogenous and algal oxygen demand would undermine effluent quality assessment and interpretation of the performance of the wastewater treatment plant.
NASA Astrophysics Data System (ADS)
Lee, Young Ju; Ahn, Hyung Joon; Lee, Gi-Ja; Jung, Gyeong Bok; Lee, Gihyun; Kim, Dohyun; Shin, Jae-Ho; Jin, Kyung-Hyun; Park, Hun-Kuk
2015-07-01
The study was to investigate the changes in biochemical properties of activated mature CD8+ T cells related to apoptosis at a molecular level. We confirmed the activation and apoptosis of CD8+ T cells by fluorescence-activated cell sorting and atomic force microscopy and then performed Raman spectral measurements on activated mature CD8+ T cells and cellular deoxyribose nucleic acid (DNA). In the activated mature CD8+ T cells, there were increases in protein spectra at 1002 and 1234 cm-1. In particular, to assess the apoptosis-related DNA spectral signatures, we investigated the spectra of the cellular DNA isolated from resting and activated mature CD8+ T cells. Raman spectra at 765 to 786 cm-1 and 1053 to 1087 cm-1 were decreased in activated mature DNA. In addition, we analyzed Raman spectrum using the multivariate statistical method including principal component analysis. Raman spectra of activated mature DNA are especially well-discriminated from those of resting DNA. Our findings regarding the biochemical and structural changes associated with apoptosis in activated mature T cells and cellular DNA according to Raman spectroscopy provide important insights into allospecific immune responses generated after organ transplantation, and may be useful for therapeutic manipulation of the immune response.
Lu, Huanping; Li, Zhian; Fu, Shenglei; Méndez, Ana; Gascó, Gabriel; Paz-Ferreiro, Jorge
2015-01-01
The main goal of phytoremediation is to improve ecosystem functioning. Soil biochemical properties are considered as effective indicators of soil quality and are sensitive to various environmental stresses, including heavy metal contamination. The biochemical response in a soil contaminated with cadmium was tested after several treatments aimed to reduce heavy metal availability including liming, biochar addition and phytoextraction using Amaranthus tricolor L. Two biochars were added to the soil: eucalyptus pyrolysed at 600 °C (EB) and poultry litter at 400 °C (PLB). Two liming treatments were chosen with the aim of bringing soil pH to the same values as in the treatments EB and PLB. The properties studied included soil microbial biomass C, soil respiration and the activities of invertase, β-glucosidase, β-glucosaminidase, urease and phosphomonoesterase. Both phytoremediation and biochar addition improved soil biochemical properties, although results were enzyme specific. For biochar addition these changes were partly, but not exclusively, mediated by alterations in soil pH. A careful choice of biochar must be undertaken to optimize the remediation process from the point of view of metal phytoextraction and soil biological activity. Copyright © 2014 Elsevier Ltd. All rights reserved.
Tzekov, Radouil; Dawson, Clint; Orlando, Megan; Mouzon, Benoit; Reed, Jon; Evans, James; Crynen, Gogce; Mullan, Michael; Crawford, Fiona
2016-01-01
Repetitive mild traumatic brain injury (r-mTBI) results in neuropathological and biochemical consequences in the human visual system. Using a recently developed mouse model of r-mTBI, with control mice receiving repetitive anesthesia alone (r-sham) we assessed the effects on the retina and optic nerve using histology, immunohistochemistry, proteomic and lipidomic analyses at 3 weeks post injury. Retina tissue was used to determine retinal ganglion cell (RGC) number, while optic nerve tissue was examined for cellularity, myelin content, protein and lipid changes. Increased cellularity and areas of demyelination were clearly detectable in optic nerves in r-mTBI, but not in r-sham. These changes were accompanied by a ~25% decrease in the total number of Brn3a-positive RGCs. Proteomic analysis of the optic nerves demonstrated various changes consistent with a negative effect of r-mTBI on major cellular processes like depolymerization of microtubules, disassembly of filaments and loss of neurons, manifested by decrease of several proteins, including neurofilaments (NEFH, NEFM, NEFL), tubulin (TUBB2A, TUBA4A), microtubule-associated proteins (MAP1A, MAP1B), collagen (COL6A1, COL6A3) and increased expression of other proteins, including heat shock proteins (HSP90B1, HSPB1), APOE and cathepsin D. Lipidomic analysis showed quantitative changes in a number of phospholipid species, including a significant increase in the total amount of lysophosphatidylcholine (LPC), including the molecular species 16:0, a known demyelinating agent. The overall amount of some ether phospholipids, like ether LPC, ether phosphatidylcholine and ether lysophosphatidylethanolamine were also increased, while the majority of individual molecular species of ester phospholipids, like phosphatidylcholine and phosphatidylethanolamine, were decreased. Results from the biochemical analysis correlate well with changes detected by histological and immunohistochemical methods and indicate the involvement of several important molecular pathways. This will allow future identification of therapeutic targets for improving the visual consequences of r-mTBI. PMID:27088355
Manoliu, Andrei; Bosch, Oliver G; Brakowski, Janis; Brühl, Annette B; Seifritz, Erich
2018-01-01
Major depressive disorder (MDD) has been proposed to represent a "disease of premature aging", which is associated with certain biomarkers of cellular ageing and numerous other age-related diseases. Over the last decade, telomere length (TL) arose as a surrogate for cellular aging. Recent data suggests that TL might be reduced in patients with MDD, however, results are still inconclusive. This might be explained by the lack of assessment of potential biochemical mediators that are directly associated with telomere shortening and frequently observed in patients with MDD. A narrative review was performed. The PubMed database was searched for relevant studies. We identified four major mediators, which are recurrently reported in patients with MDD and are associated with reduced TL: inflammation/oxidative stress, dysregulation of the hypothalamic-pituitary-adrenal axis, metabolic dysbalance including insulin resistance, and decreased brain-derived neurotrophic factor. These mediators are also mutually associated and were not systematically assessed in current studies investigating TL and MDD, which might explain inconclusive findings across current literature. Finally, we discuss possible ways to assess those mediators and potential implications of such approaches for future research. The majority of identified studies had cross-sectional designs and used heterogeneous methods to assess TL and associated relevant biochemical mediators. A better understanding of the complex interactions between biochemical mediators, somatic comorbidities and shortened telomeres in patients with MDD might further specify the pathophysiology-based conceptualization and, based on that, personalized treatment of MDD. Copyright © 2017 Elsevier B.V. All rights reserved.
[Biliary dysfunction in obese children].
Aleshina, E I; Gubonina, I V; Novikova, V P; Vigurskaia, M Iu
2014-01-01
To examine the state of the biliary system, a study of properties of bile "case-control") 100 children and adolescents aged 8 to 18 years, held checkup in consultative and diagnostic center for chronic gastroduodenitis. BMI children were divided into 2 groups: group 1-60 children with obesity (BMI of 30 to 40) and group 2-40 children with normal anthropometric indices. Survey methods included clinical examination pediatrician, endocrinologist, biochemical parameters (ALT, AST, alkaline phosphatase level, total protein, bilirubin, lipidogram, glucose, insulin, HOMA-index), ultrasound of the abdomen and retroperitoneum, EGD with aspiration of gallbladder bile. Crystallography bile produced by crystallization of biological substrates micromethods modification Prima AV, 1992. Obese children with chronic gastroduodenita more likely than children of normal weight, had complaints and objective laboratory and instrumental evidence of insulin resistance and motor disorders of the upper gastrointestinal and biliary tract, liver enlargement and biliary "sludge". Biochemical parameters of obese children indicate initial metabolic changes in carbohydrate and fat metabolism and cholestasis, as compared to control children. Colloidal properties of bile in obese children with chronic gastroduodenita reduced, as indicated by the nature of the crystallographic pattern. Conclusions: Obese children with chronic gastroduodenitis often identified enlarged liver, cholestasis and biliary dysfunction, including with the presence of sludge in the gallbladder; most often--hypertonic bile dysfunction. Biochemical features of carbohydrate and fat metabolism reflect the features of the metabolic profile of obese children. Crystallography bile in obese children reveals the instability of the colloidal structure of bile, predisposing children to biliary sludge, which is a risk factor for gallstones.
Littlejohn, George R; Mansfield, Jessica C; Parker, David; Lind, Rob; Perfect, Sarah; Seymour, Mark; Smirnoff, Nicholas; Love, John; Moger, Julian
2015-05-01
The cuticle is a ubiquitous, predominantly waxy layer on the aerial parts of higher plants that fulfils a number of essential physiological roles, including regulating evapotranspiration, light reflection, and heat tolerance, control of development, and providing an essential barrier between the organism and environmental agents such as chemicals or some pathogens. The structure and composition of the cuticle are closely associated but are typically investigated separately using a combination of structural imaging and biochemical analysis of extracted waxes. Recently, techniques that combine stain-free imaging and biochemical analysis, including Fourier transform infrared spectroscopy microscopy and coherent anti-Stokes Raman spectroscopy microscopy, have been used to investigate the cuticle, but the detection sensitivity is severely limited by the background signals from plant pigments. We present a new method for label-free, in vivo structural and biochemical analysis of plant cuticles based on stimulated Raman scattering (SRS) microscopy. As a proof of principle, we used SRS microscopy to analyze the cuticles from a variety of plants at different times in development. We demonstrate that the SRS virtually eliminates the background interference compared with coherent anti-Stokes Raman spectroscopy imaging and results in label-free, chemically specific confocal images of cuticle architecture with simultaneous characterization of cuticle composition. This innovative use of the SRS spectroscopy may find applications in agrochemical research and development or in studies of wax deposition during leaf development and, as such, represents an important step in the study of higher plant cuticles. © 2015 American Society of Plant Biologists. All Rights Reserved.
Thathapudi, Sujatha; Kodati, Vijayalakshmi; Erukkambattu, Jayashankar; Katragadda, Anuradha; Addepally, Uma; Hasan, Qurratulain
2014-01-01
Background: Polycystic ovarian syndrome (PCOS) is one of the most common endocrine conditions affecting women of reproductive age with a prevalence of approximately 5-10% worldwide. PCOS can be viewed as a heterogeneous androgen excess disorder with varying degrees of reproductive and metabolic abnormalities, whose diagnosis is based on anthropometric, biochemical and radiological abnormalities. To our knowledge, this is the first study investigating the anthropometric, biochemical and ultrasonographic characteristics of PCOS in Asian Indians of South India, using the Androgen Excess Society (AES-2006) diagnostic criteria. Objectives: To assess anthropometric, biochemical and ultrasonographic features of PCOS subgroups and controls among South Indian women using the AES-2006 criteria. Materials and Methods: Two hundred and four women clinically diagnosed with PCOS, and 204 healthy women controls aged 17 to 35 years were evaluated. PCOS was diagnosed by clinical hyperandrogenism (HA), irregular menstruation (IM), and polycystic ovary (PCO). PCOS was further categorized into phenotypic subgroups including the IM+HA+PCO (n = 181, 89%), HA+PCO (n = 23, 11%), IM+HA (n = 0), and also into obese PCOS (n = 142, 70%) and lean PCOS (n = 62, 30%) using body mass index (BMI). Anthropometric measurements and biochemical characteristics were compared among the PCOS subgroups. Results: The PCOS subgroups with regular menstrual cycles (HA+PCO), had more luteinizing hormone (LH), follicle stimulating hormone (FSH), fasting glucose, fasting insulin, and high insulin resistance (IR) expressed as the Homeostasis Model Assessment (HOMA) score, compared with the IM+HA+PCO subgroups and controls. Similarly, the obese PCOS had high BMI, waist to hip ratio (WHR), fasting glucose, LH, LH/FSH, fasting insulin, HOMA score (IR), and dyslipidemia, compared with lean PCOS and controls. Unilateral polycystic ovary was seen in 32 (15.7%) patients, and bilateral involvement in 172 (84.3%) patients. All the controls showed normal ovaries. Conclusions: Anthropometric, biochemical, and ultrasonographic findings showed significant differences among PCOS subgroups. The PCOS subgroups with regular menstrual cycles (HA+PCO), had high insulin resistance (IR) and gonadotropic hormonal abnormalities, compared with the IM+HA+PCO subgroups and controls. PMID:24696694
Biochemical Activities of 320 ToxCast Chemicals Evaluated Across 239 Functional Targets
EPA’s ToxCast research program is profiling chemical bioactivity in order to generate predictive signatures of toxicity. The present study evaluated 320 chemicals across 239 biochemical assays. ToxCast phase I chemicals include 309 unique structures, most of which are pesticide ...
Factors impacting life stage-specific sensitivity to chemicals include toxicokinetic and toxicodynamic changes. To evaluate age-related differences in the biochemical and behavioral impacts of two typical N-methyl carbamate pesticides, we systematically compared their dose-respo...
A moment-convergence method for stochastic analysis of biochemical reaction networks.
Zhang, Jiajun; Nie, Qing; Zhou, Tianshou
2016-05-21
Traditional moment-closure methods need to assume that high-order cumulants of a probability distribution approximate to zero. However, this strong assumption is not satisfied for many biochemical reaction networks. Here, we introduce convergent moments (defined in mathematics as the coefficients in the Taylor expansion of the probability-generating function at some point) to overcome this drawback of the moment-closure methods. As such, we develop a new analysis method for stochastic chemical kinetics. This method provides an accurate approximation for the master probability equation (MPE). In particular, the connection between low-order convergent moments and rate constants can be more easily derived in terms of explicit and analytical forms, allowing insights that would be difficult to obtain through direct simulation or manipulation of the MPE. In addition, it provides an accurate and efficient way to compute steady-state or transient probability distribution, avoiding the algorithmic difficulty associated with stiffness of the MPE due to large differences in sizes of rate constants. Applications of the method to several systems reveal nontrivial stochastic mechanisms of gene expression dynamics, e.g., intrinsic fluctuations can induce transient bimodality and amplify transient signals, and slow switching between promoter states can increase fluctuations in spatially heterogeneous signals. The overall approach has broad applications in modeling, analysis, and computation of complex biochemical networks with intrinsic noise.
Optical Biopsy: A New Frontier in Endoscopic Detection and Diagnosis
WANG, THOMAS D.; VAN DAM, JACQUES
2007-01-01
Endoscopic diagnosis currently relies on the ability of the operator to visualize abnormal patterns in the image created by light reflected from the mucosal surface of the gastrointestinal tract. Advances in fiber optics, light sources, detectors, and molecular biology have led to the development of several novel methods for tissue evaluation in situ. The term “optical biopsy” refers to methods that use the properties of light to enable the operator to make an instant diagnosis at endoscopy, previously possible only by using histological or cytological analysis. Promising imaging techniques include fluorescence endoscopy, optical coherence tomography, confocal microendoscopy, and molecular imaging. Point detection schemes under development include light scattering and Raman spectroscopy. Such advanced diagnostic methods go beyond standard endoscopic techniques by offering improved image resolution, contrast, and tissue penetration and providing biochemical and molecular information about mucosal disease. This review describes the basic biophysics of light-tissue interactions, assesses the strengths and weaknesses of each method, and examines clinical and preclinical evidence for each approach. PMID:15354274
Skills methods to prevent smoking.
Schinke, S P; Gilchrist, L D; Schilling, R F; Snow, W H; Bobo, J K
1986-01-01
School health educators have devoted much attention to cigarette smoking. Recent years have seen the testing of interventions to prevent smoking. To date, controlled studies have not evaluated the added value of skills methods for preventing smoking. This article describes such an evaluation with sixth-grade students from two schools. Subjects were pretested and randomly assigned to receive conventional health education methods or to receive skills intervention. Both conditions included films, peer testimonials, discussions, and homework. Health education condition subjects additionally participated in oral quizzes, games, and debates. Skills condition subjects additionally learned problem-solving, self-instruction, and interpersonal communication methods. At postintervention, skills condition subjects, more than health education condition subjects, had better scores on measures of smoking-related knowledge, attitudes, and intentions. In addition, reported cigarette use, validated by biochemical data collection, was lower in the skills condition than in the health education condition at all postintervention measurements, including a 24-month follow-up. The article discusses the strengths, limits, and implications of the study for other smoking prevention efforts in schools.
USDA-ARS?s Scientific Manuscript database
Photosynthetic potential in C3 plants is largely limited by CO2 diffusion through stomata (Ls) and mesophyll (Lm) and photo-biochemical (Lb) processes. Accurate estimation of mesophyll conductance (gm) using gas exchange (GE) and chlorophyll fluorescence (CF) parameters of the photosynthetic proces...
A stopped-flow calorimeter for biochemical applications.
Howarth, J V; Millar, N C; Gutfreund, H
1987-01-01
A rapid-response stopped-flow calorimeter for small samples of reagents is described. The construction, performance characteristics and operational limitations are described, along with an example of its ability to resolve the kinetics of an enzyme-catalysed hydrolysis. It is thought likely that the method would find useful application in a variety of chemical and biochemical investigations. PMID:3435478
NASA Astrophysics Data System (ADS)
Polyakov, V. V.
During a final 4-month stage of I-year space flight of cosmonauts Titov and Manarov, a physician, Valery Polyakov was included on a crew for the purpose of evaluating their health, correcting physical status to prepare for the spacecraft reentry and landing operations. The complex program of scientific investigations and experiments performed by a physician included an evaluation of adaptation reactions of the human body at different stages of space mission using clinicophysiological and biochemical methods; testing of alternative regimes of exercises and new countermeasures to prevent an unfavorable effect of long-term weightlessness.
Improving Marine Ecosystem Models with Biochemical Tracers
NASA Astrophysics Data System (ADS)
Pethybridge, Heidi R.; Choy, C. Anela; Polovina, Jeffrey J.; Fulton, Elizabeth A.
2018-01-01
Empirical data on food web dynamics and predator-prey interactions underpin ecosystem models, which are increasingly used to support strategic management of marine resources. These data have traditionally derived from stomach content analysis, but new and complementary forms of ecological data are increasingly available from biochemical tracer techniques. Extensive opportunities exist to improve the empirical robustness of ecosystem models through the incorporation of biochemical tracer data and derived indices, an area that is rapidly expanding because of advances in analytical developments and sophisticated statistical techniques. Here, we explore the trophic information required by ecosystem model frameworks (species, individual, and size based) and match them to the most commonly used biochemical tracers (bulk tissue and compound-specific stable isotopes, fatty acids, and trace elements). Key quantitative parameters derived from biochemical tracers include estimates of diet composition, niche width, and trophic position. Biochemical tracers also provide powerful insight into the spatial and temporal variability of food web structure and the characterization of dominant basal and microbial food web groups. A major challenge in incorporating biochemical tracer data into ecosystem models is scale and data type mismatches, which can be overcome with greater knowledge exchange and numerical approaches that transform, integrate, and visualize data.
Hernández-Toloza, Johana Esther; Rincón-Serrano, María de Pilar; Celis-Bustos, Yamile Adriana; Aguillón, Claudia Inés
2016-01-01
Global epidemiology of non-tuberculous mycobacteria (NTM) is unknown due to the fact that notification is not required in many countries, however the number of infection reports and outbreaks caused by NTM suggest a significant increase in the last years. Traditionally, mycobacteria identification is made through biochemical profiles which allow to differentiate M. tuberculosis from NTM, and in some cases the mycobacteria species. Nevertheless, these methods are technically cumbersome and time consuming. On the other hand, the introduction of methods based on molecular biology has improved the laboratory diagnosis of NTM. To establish the NTM frequency in positive cultures for acid-fast bacilli (AAFB) which were sent to Laboratorio de Salud Pública de Bogotá over a 12 month period. A total of 100 positive cultures for acid-fast bacilli from public and private hospitals from Bogotá were identified by both biochemical methods and the molecular methods PRA (PCR-restriction enzyme analysis) and multiplex-PCR. Furthermore, low prevalence mycobacteria species and non-interpretable results were confirmed by 16SrDNA sequentiation analysis. Identification using the PRA method showed NMT occurrence in 11% of cultures. In addition, this molecular methodology allowed to detect the occurrence of more than one mycobacteria in 4% of the cultures. Interestingly, a new M. kubicae pattern of PCR-restriction analysis is reported in our study. Using a mycobacteria identification algorithm, which includes the molecular method PRA, improves the diagnostic power of conventional methods and could help to advance both NTM epidemiology knowledge and mycobacteriosis control. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.
Nanoparticles as biochemical sensors
El-Ansary, Afaf; Faddah, Layla M
2010-01-01
There is little doubt that nanoparticles offer real and new opportunities in many fields, such as biomedicine and materials science. Such particles are small enough to enter almost all areas of the body, including cells and organelles, potentially leading to new approaches in nanomedicine. Sensors for small molecules of biochemical interest are of critical importance. This review is an attempt to trace the use of nanomaterials in biochemical sensor design. The possibility of using nanoparticles functionalized with antibodies as markers for proteins will be elucidated. Moreover, capabilities and applications for nanoparticles based on gold, silver, magnetic, and semiconductor materials (quantum dots), used in optical (absorbance, luminescence, surface enhanced Raman spectroscopy, surface plasmon resonance), electrochemical, and mass-sensitive sensors will be highlighted. The unique ability of nanosensors to improve the analysis of biochemical fluids is discussed either through considering the use of nanoparticles for in vitro molecular diagnosis, or in the biological/biochemical analysis for in vivo interaction with the human body. PMID:24198472
Ün, Sıtkı; Türk, Hakan; Koca, Osman; Divrik, Rauf Taner; Zorlu, Ferruh
2015-01-01
Objective: This study was conducted to research the factors determining biochemical recurrence (BCR) in low-risk localized prostate cancer patients who underwent radical prostatectomy (RP). Materials and methods: We retrospectively analyzed the data of 504 patients who had undergone RP between 2003 and 2013 at our clinic. One hundred and fifty-two patients who underwent RP for low-risk prostate cancer were included in the study. Results: The mean follow-up period for patients was 58.7 (21–229) months. The mean age of the patients was 63.7±7.2 years (49–79). The mean prostate specific antigen (PSA) value was 5.25±4.22 ng/mL (3.58–9.45). The BCR rate after the operation was 25% (38/152). In the univariate analysis, recurrence determining factors were shown to include extracapsular involvement (ECI) (p=0.004), capsular invasion (CI) (p=0.001), age (p=0.014), and tumor size (p=0.006). However, only CI was found to be significant in multivariate analysis (p=0.001). Conclusion: Capsular invasion is an independent risk factor in low-risk prostate cancer patients who underwent RP for BCR. PMID:26328203
Le Pape, Sylvain; Dimitrova, Elena; Hannaert, Patrick; Konovalov, Alexander; Volmer, Romain; Ron, David; Thuillier, Raphaël; Hauet, Thierry
2014-08-25
The unfolded protein response (UPR)--the endoplasmic reticulum stress response--is found in various pathologies including ischemia-reperfusion injury (IRI). However, its role during IRI is still unclear. Here, by combining two different bioinformatical methods--a method based on ordinary differential equations (Time Series Network Inference) and an algebraic method (probabilistic polynomial dynamical systems)--we identified the IRE1α-XBP1 and the ATF6 pathways as the main UPR effectors involved in cell's adaptation to IRI. We validated these findings experimentally by assessing the impact of their knock-out and knock-down on cell survival during IRI. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Survey of Biochemical Education in Japanese Universities.
ERIC Educational Resources Information Center
Kagawa, Yasuo
1995-01-01
Reports findings of questionnaires sent to faculty in charge of biochemical education in medical schools and other programs from dentistry to agriculture. Total class hours have declined since 1984. New trends include bioethics and computer-assisted learning. Tables show trends in lecture hours, lecture content, laboratory hours, core subject…
BIOCHEMICAL HOMEOSTASIS AND BODY GROWTH ARE RELIABLE END POINTS IN CLINICAL NUTRITION TRIALS
USDA-ARS?s Scientific Manuscript database
Studies of biochemical homeostasis and/or body growth have been included as outcome variables in most nutrition trials in paediatric patients. Moreover, these outcome variables have provided important insights into the nutrient requirements of infants and children, and continue to do so. Examples ...
Rapid Methods for Biochemical Testing of Anaerobic Bacteria
Schreckenberger, Paul C.; Blazevic, Donna J.
1974-01-01
Rapid biochemical tests for nitrate, indole, gelatin, starch, esculin, and o-nitrophenyl-β-D-galactopyranoside were performed on 112 strains of anaerobic bacteria. All tests were incubated under aerobic conditions, and results were recorded within 4 h. The tests for nitrate, indole, and starch showed a 95% or greater correlation when compared to the standard biochemical tests. Tests for esculin and gelatin showed an agreement of 86 and 77%, respectively. PathoTec test strips for nitrate, indole, esculin, o-nitrophenyl-β-D-galactopyranoside, Voges-Proskauer, and urease were also tested and showed encouraging results. PMID:4613268
Bleakley, Chris M; Davison, Gareth W
2010-02-01
Cold-water immersion (CWI) is a popular recovery intervention after exercise. The scientific rationale is not clear, and there are no clear guidelines for its use. The aim of this review was to study the physiological and biochemical effect of short periods of CWI. A computer-based literature search, citation tracking and related articles searches were undertaken. Primary research studies using healthy human participants, immersed in cold water (<15 degrees C), for 5 min durations or less were included. Data were extracted on body temperature, cardiovascular, respiratory and biochemical response. 16 studies were included. Sample size was restricted, and there was a large degree of study heterogeneity. CWI was associated with an increase in heart rate, blood pressure, respiratory minute volume and metabolism. Decreases in end tidal carbon dioxide partial pressure and a decrease in cerebral blood flow were also reported. There was evidence of increases in peripheral catecholamine concentration, oxidative stress and a possible increase in free-radical-species formation. The magnitude of these responses may be attenuated with acclimatisation. CWI induces significant physiological and biochemical changes to the body. Much of this evidence is derived from full body immersions using resting healthy participants. The physiological and biochemical rationale for using short periods of CWI in sports recovery still remains unclear.
Correlations between female breast density and biochemical markers.
Kim, Ji-Hye; Lee, Hae-Kag; Cho, Jae-Hwan; Park, Hyong-Keun; Yang, Han-Jun
2015-07-01
[Purpose] The aim of this study was to identify biochemical markers related to breast density. The study was performed with 200 patients who received mammography and biochemical marker testing between March 1, 2014 to October 1, 2014. [Subjects and Methods] Following the American College of Radiology, Breast Imaging Reporting and Data System (ACR BI-RADS), breast parenchymal pattern density from mammography was categorized into four grades: grade 1, almost entirely fat; grade 2, fibroglandular densities; grade 3, heterogeneously dense; and grade 4, extremely dense. Regarding biochemical markers, subjects underwent blood and urine tests after a 12-h fast. We analyzed correlations among breast density, general characteristics, and biochemical markers. [Results] Breast density-related factors were age, height, weight, body mass index (BMI), hematocrit, MCH, RDW, AST, ALT, ALP, uric acid, γGT, triglycerides, total cholesterol, HDL-cholesterol, and LDL-cholesterol. [Conclusion] The results can be used as basic and comparative data for the prevention and early control of breast cancer.
In singulo biochemistry: when less is more.
Bustamante, Carlos
2008-01-01
It has been over one-and-a-half decades since methods of single-molecule detection and manipulation were first introduced in biochemical research. Since then, the application of these methods to an expanding variety of problems has grown at a vertiginous pace. While initially many of these experiments led more to confirmatory results than to new discoveries, today single-molecule methods are often the methods of choice to establish new mechanism-based results in biochemical research. Throughout this process, improvements in the sensitivity, versatility, and both spatial and temporal resolution of these techniques has occurred hand in hand with their applications. We discuss here some of the advantages of single-molecule methods over their bulk counterparts and argue that these advantages should help establish them as essential tools in the technical arsenal of the modern biochemist.
A Method for Finding Metabolic Pathways Using Atomic Group Tracking.
Huang, Yiran; Zhong, Cheng; Lin, Hai Xiang; Wang, Jianyi
2017-01-01
A fundamental computational problem in metabolic engineering is to find pathways between compounds. Pathfinding methods using atom tracking have been widely used to find biochemically relevant pathways. However, these methods require the user to define the atoms to be tracked. This may lead to failing to predict the pathways that do not conserve the user-defined atoms. In this work, we propose a pathfinding method called AGPathFinder to find biochemically relevant metabolic pathways between two given compounds. In AGPathFinder, we find alternative pathways by tracking the movement of atomic groups through metabolic networks and use combined information of reaction thermodynamics and compound similarity to guide the search towards more feasible pathways and better performance. The experimental results show that atomic group tracking enables our method to find pathways without the need of defining the atoms to be tracked, avoid hub metabolites, and obtain biochemically meaningful pathways. Our results also demonstrate that atomic group tracking, when incorporated with combined information of reaction thermodynamics and compound similarity, improves the quality of the found pathways. In most cases, the average compound inclusion accuracy and reaction inclusion accuracy for the top resulting pathways of our method are around 0.90 and 0.70, respectively, which are better than those of the existing methods. Additionally, AGPathFinder provides the information of thermodynamic feasibility and compound similarity for the resulting pathways.
Complexity reduction of biochemical rate expressions.
Schmidt, Henning; Madsen, Mads F; Danø, Sune; Cedersund, Gunnar
2008-03-15
The current trend in dynamical modelling of biochemical systems is to construct more and more mechanistically detailed and thus complex models. The complexity is reflected in the number of dynamic state variables and parameters, as well as in the complexity of the kinetic rate expressions. However, a greater level of complexity, or level of detail, does not necessarily imply better models, or a better understanding of the underlying processes. Data often does not contain enough information to discriminate between different model hypotheses, and such overparameterization makes it hard to establish the validity of the various parts of the model. Consequently, there is an increasing demand for model reduction methods. We present a new reduction method that reduces complex rational rate expressions, such as those often used to describe enzymatic reactions. The method is a novel term-based identifiability analysis, which is easy to use and allows for user-specified reductions of individual rate expressions in complete models. The method is one of the first methods to meet the classical engineering objective of improved parameter identifiability without losing the systems biology demand of preserved biochemical interpretation. The method has been implemented in the Systems Biology Toolbox 2 for MATLAB, which is freely available from http://www.sbtoolbox2.org. The Supplementary Material contains scripts that show how to use it by applying the method to the example models, discussed in this article.
A Method for Finding Metabolic Pathways Using Atomic Group Tracking
Zhong, Cheng; Lin, Hai Xiang; Wang, Jianyi
2017-01-01
A fundamental computational problem in metabolic engineering is to find pathways between compounds. Pathfinding methods using atom tracking have been widely used to find biochemically relevant pathways. However, these methods require the user to define the atoms to be tracked. This may lead to failing to predict the pathways that do not conserve the user-defined atoms. In this work, we propose a pathfinding method called AGPathFinder to find biochemically relevant metabolic pathways between two given compounds. In AGPathFinder, we find alternative pathways by tracking the movement of atomic groups through metabolic networks and use combined information of reaction thermodynamics and compound similarity to guide the search towards more feasible pathways and better performance. The experimental results show that atomic group tracking enables our method to find pathways without the need of defining the atoms to be tracked, avoid hub metabolites, and obtain biochemically meaningful pathways. Our results also demonstrate that atomic group tracking, when incorporated with combined information of reaction thermodynamics and compound similarity, improves the quality of the found pathways. In most cases, the average compound inclusion accuracy and reaction inclusion accuracy for the top resulting pathways of our method are around 0.90 and 0.70, respectively, which are better than those of the existing methods. Additionally, AGPathFinder provides the information of thermodynamic feasibility and compound similarity for the resulting pathways. PMID:28068354
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wunschel, David S.; Kreuzer-Martin, Helen W.; Antolick, Kathryn C.
2009-12-01
This report describes method development and preliminary evaluation for analyzing castor samples for signatures of purifying ricin. Ricin purification from the source castor seeds is essentially a problem of protein purification using common biochemical methods. Indications of protein purification will likely manifest themselves as removal of the non-protein fractions of the seed. Two major, non-protein, types of biochemical constituents in the seed are the castor oil and various carbohydrates. The oil comprises roughly half the seed weight while the carbohydrate component comprises roughly half of the remaining “mash” left after oil and hull removal. Different castor oil and carbohydrate componentsmore » can serve as indicators of specific toxin processing steps. Ricinoleic acid is a relatively unique fatty acid in nature and is the most abundant component of castor oil. The loss of ricinoleic acid indicates a step to remove oil from the seeds. The relative amounts of carbohydrates and carbohydrate-like compounds, including arabinose, xylose, myo-inositol fucose, rhamnose, glucosamine and mannose detected in the sample can also indicate specific processing steps. For instance, the differential loss of arabinose relative to mannose and N-acetyl glucosamine indicates enrichment for the protein fraction of the seed using protein precipitation. The methods developed in this project center on fatty acid and carbohydrate extraction from castor samples followed by derivatization to permit analysis by gas chromatography-mass spectrometry (GC-MS). Method descriptions herein include: the source and preparation of castor materials used for method evaluation, the equipment and description of procedure required for chemical derivatization, and the instrument parameters used in the analysis. Two types of derivatization methods describe analysis of carbohydrates and one procedure for analysis of fatty acids. Two types of GC-MS analysis is included in the method development, one employing a quadrupole MS system for compound identification and an isotope ratio MS for measuring the stable isotope ratios of deuterium and hydrogen (D/H) in fatty acids. Finally, the method for analyzing the compound abundance data is included. This study indicates that removal of ricinoleic acid is a conserved consequence of each processing step we tested. Furthermore, the stable isotope D/H ratio of ricinoleic acid distinguished between two of the three castor seed sources. Concentrations of arabinose, xylose, mannose, glucosamine and myo-inositol differentiated between crude or acetone extracted samples and samples produced by protein precipitation. Taken together these data illustrate the ability to distinguish between processes used to purify a ricin sample as well as potentially the source seeds.« less
Supercolor coding methods for large-scale multiplexing of biochemical assays.
Rajagopal, Aditya; Scherer, Axel; Homyk, Andrew; Kartalov, Emil
2013-08-20
We present a novel method for the encoding and decoding of multiplexed biochemical assays. The method enables a theoretically unlimited number of independent targets to be detected and uniquely identified in any combination in the same sample. For example, the method offers easy access to 12-plex and larger PCR assays, as contrasted to the current 4-plex assays. This advancement would allow for large panels of tests to be run simultaneously in the same sample, saving reagents, time, consumables, and manual labor, while also avoiding the traditional loss of sensitivity due to sample aliquoting. Thus, the presented method is a major technological breakthrough with far-reaching impact on biotechnology, biomedical science, and clinical diagnostics. Herein, we present the mathematical theory behind the method as well as its experimental proof of principle using Taqman PCR on sequences specific to infectious diseases.
NASA Astrophysics Data System (ADS)
Iskhakova, K.; Murzakhanov, F.; Mamin, G.; Putlyaev, V.; Klimashina, E.; Fadeeva, I.; Fomin, A.; Barinov, S.; Maltsev, A.; Bakhteev, S.; Yusupov, R.; Gafurov, M.; Orlinskii, S.
2018-05-01
Calcium phosphates (CaP) are exploited in many fields of science, including geology, chemistry, biology and medicine due to their abundance in the nature and presence in the living organism. Various analytical and biochemical methods are used for controlling their chemical content, structure, morphology, etc. Unfortunately, magnetic resonance techniques are usually not even considered as necessary tools for CaP inspection. Some aspects of application of the commercially realized electron paramagnetic resonance (EPR) approaches for characterization of CaP powders and ceramics (including the nanosized materails) such as hydroxyapatite and tricalcium phosphates of biogenic and synthetic origins containing intrinsic impurities or intentional dopants are demonstrated. The key features and advantages of the EPR techniques for CaP based materials characterization that could compliment the data obtained with the recognized analytical methods are pointed out.
Ambroziak, Urszula; Kuryłowicz, Alina; Kępczyńska-Nyk, Anna; Kondracka, Agnieszka; Gajda, Sylvia; Sieńko, Damian
2018-06-01
The diagnosis of biochemical hyperandrogenism is still challenging because a set of appropriate, recommended diagnostic tests has not been established. In our study, we aimed to answer the question of whether salivary testosterone is a reliable test to establish the diagnosis of biochemical hyperandrogenism as compared to serum total testosterone (TT) measured either by liquid chromatography-tandem mass spectrometry (LC-MS/MS) or immunoassay and to assess which set of biochemical tests would be the most appropriate for the identification of biochemical hyperandrogenism. A total of 39 women, aged 18-45 years, with clinical or biochemical hyperandrogenism and 41 healthy individuals, aged 19-45 years, were enrolled in the study. Salivary testosterone was measured using the Salimetrics test. Serum TT was measured either using the LC-MS/MS method or immunoassay, and dehydroepiandrosterone sulphate (DHEA-S) and androstenedione were measured using LC-MS/MS. In 15 of 17 (88%) patients with elevated serum TT measured by LC-MS/MS and in 14 of 16 (87%) measured with immunoassay, salivary testosterone showed normal levels. In 11 of 39 women (28%) with normal serum testosterone levels, DHEA-S was elevated. All patients with elevated androstenedione presented with an elevated concentration of either serum testosterone or DHEA-S. Salivary testosterone measurement may lead to the underdiagnosis of biochemical hyperandrogenism. Both serum testosterone and DHEA-S should be measured in the endocrine work-up toward biochemical hyperandrogenism. © 2018 Japan Society of Obstetrics and Gynecology.
Biochemical abnormalities in neonatal seizures.
Sood, Arvind; Grover, Neelam; Sharma, Roshan
2003-03-01
The presence of seizure does not constitute a diagnoses but it is a symptom of an underlying central nervous system disorder due to systemic or biochemical disturbances. Biochemical disturbances occur frequently in the neonatal seizures either as an underlying cause or as an associated abnormality. In their presence, it is difficult to control seizure and there is a risk of further brain damage. Early recognition and treatment of biochemical disturbances is essential for optimal management and satisfactory long term outcome. The present study was conducted in the department of pediatrics in IGMC Shimla on 59 neonates. Biochemical abnormalities were detected in 29 (49.15%) of cases. Primary metabolic abnormalities occurred in 10(16.94%) cases of neonatal seizures, most common being hypocalcaemia followed by hypoglycemia, other metabolic abnormalities include hypomagnesaemia and hyponateremia. Biochemical abnormalities were seen in 19(38.77%) cases of non metabolic seizure in neonates. Associated metabolic abnormalities were observed more often with Hypoxic-ischemic-encephalopathy (11 out of 19) cases and hypoglycemia was most common in this group. No infant had hyponateremia, hyperkelemia or low zinc level.
Modelling and analysis of the sugar cataract development process using stochastic hybrid systems.
Riley, D; Koutsoukos, X; Riley, K
2009-05-01
Modelling and analysis of biochemical systems such as sugar cataract development (SCD) are critical because they can provide new insights into systems, which cannot be easily tested with experiments; however, they are challenging problems due to the highly coupled chemical reactions that are involved. The authors present a stochastic hybrid system (SHS) framework for modelling biochemical systems and demonstrate the approach for the SCD process. A novel feature of the framework is that it allows modelling the effect of drug treatment on the system dynamics. The authors validate the three sugar cataract models by comparing trajectories computed by two simulation algorithms. Further, the authors present a probabilistic verification method for computing the probability of sugar cataract formation for different chemical concentrations using safety and reachability analysis methods for SHSs. The verification method employs dynamic programming based on a discretisation of the state space and therefore suffers from the curse of dimensionality. To analyse the SCD process, a parallel dynamic programming implementation that can handle large, realistic systems was developed. Although scalability is a limiting factor, this work demonstrates that the proposed method is feasible for realistic biochemical systems.
Partially reduced graphene oxide based FRET on fiber optic interferometer for biochemical detection
NASA Astrophysics Data System (ADS)
Yao, B. C.; Wu, Y.; Yu, C. B.; He, J. R.; Rao, Y. J.; Gong, Y.; Chen, Y. F.; Li, Y. R.
2017-04-01
An all-fiber graphene oxide (GO) based 'FRET on Fiber' concept is proposed and applied in biochemical detections. This method is of both good selectivity and high sensitivity, with detection limits of 1.2 nM, 1.3 μM and 1 pM, for metal ion, dopamine and single-stranded DNA (ssDNA), respectively.
Chudobova, Dagmar; Dostalova, Simona; Ruttkay-Nedecky, Branislav; Guran, Roman; Rodrigo, Miguel Angel Merlos; Tmejova, Katerina; Krizkova, Sona; Zitka, Ondrej; Adam, Vojtech; Kizek, Rene
2015-01-01
In this study, we focused on the effect of heavy metal ions in resistant strains of gram-positive bacteria Staphylococcus aureus using biochemical methods and mass spectrometry. Five nitrate solutions of heavy metals (Ag(+), Cu(2+), Cd(2+), Zn(2+) and Pb(2+)) were used to create S. aureus resistant strains. Biochemical changes of resistant strains in comparison with the non-resistant control strain of S. aureus were observed by microbiological (measuring - growth curves and inhibition zones) and spectrophotometric methods (antioxidant activity and alaninaminotransferase, aspartateaminotransferase, alkaline phosphatase, γ-glutamyltransferase activities). Mass spectrometry was employed for the qualitative analysis of the samples (changes in S. aureus protein composition) and for the identification of the strains database MALDI Biotyper was employed. Alterations, in terms of biochemical properties and protein composition, were observed in resistant strains compared to non-resistant control strain. Our results describe the possible option for the analysis of S. aureus resistant strains and may thus serve as a support for monitoring of changes in genetic information caused by the forming of resistance to heavy metals. Copyright © 2014 Elsevier GmbH. All rights reserved.
Xu, Xiaoli; Zhang, Song; Chen, Hui; Kong, Jilie
2009-11-15
Micro-total analysis systems (microTAS) integrate different analytical operations like sample preparation, separation and detection into a single microfabricated device. With the outstanding advantages of low cost, satisfactory analytical efficiency and flexibility in design, highly integrated and miniaturized devices from the concept of microTAS have gained widespread applications, especially in biochemical assays. Electrochemistry is shown to be quite compatible with microanalytical systems for biochemical assays, because of its attractive merits such as simplicity, rapidity, high sensitivity, reduced power consumption, and sample/reagent economy. This review presents recent developments in the integration of electrochemistry in microdevices for biochemical assays. Ingenious microelectrode design and fabrication methods, and versatility of electrochemical techniques are involved. Practical applications of such integrated microsystem in biochemical assays are focused on in situ analysis, point-of-care testing and portable devices. Electrochemical techniques are apparently suited to microsystems, since easy microfabrication of electrochemical elements and a high degree of integration with multi-analytical functions can be achieved at low cost. Such integrated microsystems will play an increasingly important role for analysis of small volume biochemical samples. Work is in progress toward new microdevice design and applications.
Yue, Lifang; Lv, Hexin; Zhen, Jing; Jiang, Shengping; Jia, Shiru; Shen, Shigang; Gao, Lu; Dai, Yujie
2016-04-28
Preservation of fresh algae plays an important role in algae seed subculture and aquaculture. The determination and examination of the changes of cell viability, composition, and bacterial species during storage would help to take suitable preservation methods to prolong the preservation time of fresh algae. Nostoc flagelliforme is a kind of edible cyanobacterium with important herbal and dietary values. This article investigated the changes of bacterial species and biochemical characteristics of fresh N. flagelliforme concentrate during natural storage. It was found that the viability of cells decreased along with the storage time. Fourteen bacteria strains in the algae concentrate were identified by PCR-DGGE and were grouped into four phyla, including Cyanobacteria, Firmicutes, Proteobacteria, and Bacteroidetes. Among them, Enterococcus viikkiensis may be a concern in the preservation. Eleven volatile organic compounds were identified from N. flagelliforme cells, in which geosmin could be treated as an indicator of the freshness of N. flagelliforme. The occurrence of indole compound may be an indicator of the degradation of cells.
NASA Astrophysics Data System (ADS)
McKnight, Timothy E.; Melechko, Anatoli V.; Griffin, Guy D.; Guillorn, Michael A.; Merkulov, Vladimir I.; Serna, Francisco; Hensley, Dale K.; Doktycz, Mitchel J.; Lowndes, Douglas H.; Simpson, Michael L.
2003-05-01
We demonstrate the integration of vertically aligned carbon nanofibre (VACNF) elements with the intracellular domains of viable cells for controlled biochemical manipulation. Deterministically synthesized VACNFs were modified with either adsorbed or covalently-linked plasmid DNA and were subsequently inserted into cells. Post insertion viability of the cells was demonstrated by continued proliferation of the interfaced cells and long-term (> 22 day) expression of the introduced plasmid. Adsorbed plasmids were typically desorbed in the intracellular domain and segregated to progeny cells. Covalently bound plasmids remained tethered to nanofibres and were expressed in interfaced cells but were not partitioned into progeny, and gene expression ceased when the nanofibre was no longer retained. This provides a method for achieving a genetic modification that is non-inheritable and whose extent in time can be directly and precisely controlled. These results demonstrate the potential of VACNF arrays as an intracellular interface for monitoring and controlling subcellular and molecular phenomena within viable cells for applications including biosensors, in vivo diagnostics, and in vivo logic devices.
Bacteriology of Spoilage of Fish Muscle1
Lerke, Peter; Adams, Ralph; Farber, Lionel
1965-01-01
A total of 807 bacterial isolates from fresh and spoiling fillets of English sole (Parophrys vetulus) stored at 5 C were classified as to genus and tested for various biochemical activities, including the ability to spoil sterile muscle press juice at 5 C. Production of off-odor, volatile reducing substances, and trimethylamine was used to estimate spoilage. It was found that (i) spoilers could be distinguished from nonspoilers on the basis of the juice spoilage test, (ii) differentiation between spoilers and nonspoilers could not be achieved by means of the usual biochemical tests, (iii) no micrococci, flavobacteria, and “coryneforms” were spoilers, (iv) certain specific subgroups of the genus Pseudomonas consisted exclusively of spoilers whereas others were inactive, (v) the genus Achromobacter likewise consisted of spoilers and nonspoilers, and (vi) “coliforms” could produce spoilage. It was concluded that a method is now available to determine directly and unequivocally the role played in spoilage by various bacterial groups and that it is no longer necessary to rely on indirect evidence. PMID:14339271
NASA Astrophysics Data System (ADS)
Lieberman, Robert A.
Various paper on chemical, biochemical, and environmental fiber sensors are presented. Some of the individual topics addressed include: evanescent-wave fiber optic (FO) biosensor, refractive-index sensors based on coupling to high-index multimode overlays, advanced technique in FO sensors, design of luminescence-based temperature sensors, NIR fluorescence in FO applications, FO sensor based on microencapsulated reagents, emitters and detectors for optical gas and chemical sensing, tunable fiber laser source for methane detection at 1.68 micron, FO fluorometer based on a dual-wavelength laser excitation source, thin polymer films as active components of FO chemical sensors, submicron optical sources for single macromolecule detection, nanometer optical fiber pH sensor. Also discussed are: microfabrication of optical sensor array, luminescent FO sensor for the measurement of pH, time-domain fluorescence methods as applied to pH sensing, characterization of a sol-gel-entrapped artificial receptor, FO technology for nuclear waste cleanup, spectroscopic gas sensing with IR hollow waveguides, dissolved-oxygen quenching of in situ fluorescence measurements.
Some Biochemical and Hematological Parameters among Petrol Station Attendants: A Comparative Study
Abou-ElWafa, Hala Samir; Albadry, Ahmed A.; Bazeed, Fagr B.
2015-01-01
Objective. To describe selected biochemical and hematological parameters (blood picture, liver enzymes, and kidney functions) in petrol station attendants in Mansoura city. Methods. This is a comparative cross-sectional study. The exposed group included 102 petrol station attendants. They were compared to a matched group of healthy 102 male service and office workers at the Faculty of Medicine, Mansoura University. The results of blood picture, liver enzymes, and kidney functions were compared between both groups. Results. Mean Red Blood Cells (RBCs) count, hemoglobin level, and Hematocrit (HCT) level were significantly lower in petrol station attendants than the comparison group. All other blood picture parameters showed nonsignificant difference between both groups. Liver enzymes, renal functions, serum albumin, and total protein showed statistically nonsignificant difference between both groups except for alanine aminotransferase (ALT) which was significantly higher in petrol station attendants. Conclusions. Some laboratory parameters among petrol station attendants showed changes that could be attributed to workplace exposure and should be given attention at preemployment and periodic medical examination. PMID:26634207
The coupled bio-chemo-electro-mechanical behavior of glucose exposed arterial elastin
NASA Astrophysics Data System (ADS)
Zhang, Yanhang; Li, Jiangyu; Boutis, Gregory S.
2017-04-01
Elastin, the principle protein component of the elastic fiber, is a critical extracellular matrix (ECM) component of the arterial wall providing structural resilience and biological signaling essential in vascular morphogenesis and maintenance of mechanical homeostasis. Pathogenesis of many cardiovascular diseases have been associated with alterations of elastin. As a long-lived ECM protein that is deposited and organized before adulthood, elastic fibers can suffer from cumulative effects of biochemical exposure encountered during aging and/or disease, which greatly compromise their mechanical function. This review article covers findings from recent studies of the mechanical and structural contribution of elastin to vascular function, and the effects of biochemical degradation. Results from diverse experimental methods including tissue-level mechanical characterization, fiber-level nonlinear optical imaging, piezoelectric force microscopy, and nuclear magnetic resonance are reviewed. The intriguing coupled bio-chemo-electro-mechanical behavior of elastin calls for a multi-scale and multi-physical understanding of ECM mechanics and mechanobiology in vascular remodeling.
Fimognari, Nicholas; Hollings, Ashley; Lam, Virginie; Tidy, Rebecca J; Kewish, Cameron M; Albrecht, Matthew A; Takechi, Ryu; Mamo, John C L; Hackett, Mark J
2018-06-14
Western society is facing a health epidemic due to the increasing incidence of dementia in ageing populations, and there are still few effective diagnostic methods, minimal treatment options, and no cure. Ageing is the greatest risk factor for memory loss that occurs during the natural ageing process, as well as being the greatest risk factor for neurodegenerative disease such as Alzheimer's disease. Therefore, greater understanding of the biochemical pathways that drive a healthy ageing brain towards dementia (pathological ageing or Alzheimer's disease), is required to accelerate the development of improved diagnostics and therapies. Unfortunately, many animal models of dementia model chronic amyloid precursor protein over-expression, which although highly relevant to mechanisms of amyloidosis and familial Alzheimer's disease, does not model well dementia during the natural ageing process. A promising animal model reported to model mechanisms of accelerated natural ageing and memory impairments, is the senescence accelerated murine prone strain 8 (SAMP8), which has been adopted by many research group to study the biochemical transitions that occur during brain ageing. A limitation to traditional methods of biochemical characterisation is that many important biochemical and elemental markers (lipid saturation, lactate, transition metals) cannot be imaged at meso- or micro-spatial resolution. Therefore, in this investigation we report the first multi-modal biospectroscopic characterisation of the SAMP8 model, and have identified important biochemical and elemental alterations, and co-localisations, between 4 month old SAMP8 mice and the relevant control (SAMR1) mice. Specifically, we demonstrate direct evidence of altered metabolism and disturbed lipid homeostasis within corpus callosum white matter, in addition to localised hippocampal metal deficiencies, in the accelerated ageing phenotype. Such findings have important implication for future research aimed at elucidating specific biochemical pathways for therapeutic intervention.
Biosensor-based small molecule fragment screening with biolayer interferometry
NASA Astrophysics Data System (ADS)
Wartchow, Charles A.; Podlaski, Frank; Li, Shirley; Rowan, Karen; Zhang, Xiaolei; Mark, David; Huang, Kuo-Sen
2011-07-01
Biosensor-based fragment screening is a valuable tool in the drug discovery process. This method is advantageous over many biochemical methods because primary hits can be distinguished from non-specific or non-ideal interactions by examining binding profiles and responses, resulting in reduced false-positive rates. Biolayer interferometry (BLI), a technique that measures changes in an interference pattern generated from visible light reflected from an optical layer and a biolayer containing proteins of interest, is a relatively new method for monitoring small molecule interactions. The BLI format is based on a disposable sensor that is immersed in 96-well or 384-well plates. BLI has been validated for small molecule detection and fragment screening with model systems and well-characterized targets where affinity constants and binding profiles are generally similar to those obtained with surface plasmon resonsance (SPR). Screens with challenging targets involved in protein-protein interactions including BCL-2, JNK1, and eIF4E were performed with a fragment library of 6,500 compounds, and hit rates were compared for these targets. For eIF4E, a protein containing a PPI site and a nucleotide binding site, results from a BLI fragment screen were compared to results obtained in biochemical HTS screens. Overlapping hits were observed for the PPI site, and hits unique to the BLI screen were identified. Hit assessments with SPR and BLI are described.
NASA Astrophysics Data System (ADS)
Kuo, Chun Wei; Hao Huang, Kuan; Hsu, Bing Mu; Tsai, Hsien Lung; Tseng, Shao Feng; Shen, Tsung Yu; Kao, Po Min; Shen, Shu Min; Chen, Jung Sheng
2013-04-01
Salmonella spp. is one of the most important causal agents of waterborne diseases. The taxonomy of Salmonella is very complicated and its genus comprises more than 2,500 serotypes. The detection of Salmonella in environmental water samples by routines culture methods using selective media and characterization of suspicious colonies based on biochemical tests and serological assay are generally time consuming. To overcome this drawback, it is desirable to use effective method which provides a higher discrimination and more rapid identification about Salmonella in environmental water. The aim of this study is to investigate the occurrence of Salmonella using molecular technology and to identify the serovars of Salmonella isolates from 70 environmental water samples in Taiwan. The analytical procedures include membrane filtration, non-selective pre-enrichment, selective enrichment of Salmonella. After that, we isolated Salmonella strains by selective culture plates. Both selective enrichment and culture plates were detected by Polymerase Chain Reaction (PCR). Finally, the serovars of Salmonella were confirmed by using biochemical tests and serological assay. In this study, 15 water samples (21.4%) were identified as Salmonella by PCR. The positive water samples will further identify their serotypes by culture method. The presence of Salmonella in environmental water indicates the possibility of waterborne transmission in drinking watershed. Consequently, the authorities need to provide sufficient source protection and to maintain the system for disease prevention. Keywords: Salmonella spp., serological assay, PCR
Using Blood Indexes to Predict Overweight Statuses: An Extreme Learning Machine-Based Approach
Chen, Huiling; Yang, Bo; Liu, Dayou; Liu, Wenbin; Liu, Yanlong; Zhang, Xiuhua; Hu, Lufeng
2015-01-01
The number of the overweight people continues to rise across the world. Studies have shown that being overweight can increase health risks, such as high blood pressure, diabetes mellitus, coronary heart disease, and certain forms of cancer. Therefore, identifying the overweight status in people is critical to prevent and decrease health risks. This study explores a new technique that uses blood and biochemical measurements to recognize the overweight condition. A new machine learning technique, an extreme learning machine, was developed to accurately detect the overweight status from a pool of 225 overweight and 251 healthy subjects. The group included 179 males and 297 females. The detection method was rigorously evaluated against the real-life dataset for accuracy, sensitivity, specificity, and AUC (area under the receiver operating characteristic (ROC) curve) criterion. Additionally, the feature selection was investigated to identify correlating factors for the overweight status. The results demonstrate that there are significant differences in blood and biochemical indexes between healthy and overweight people (p-value < 0.01). According to the feature selection, the most important correlated indexes are creatinine, hemoglobin, hematokrit, uric Acid, red blood cells, high density lipoprotein, alanine transaminase, triglyceride, and γ-glutamyl transpeptidase. These are consistent with the results of Spearman test analysis. The proposed method holds promise as a new, accurate method for identifying the overweight status in subjects. PMID:26600199
Swaminathan Iyer, K; Gaikwad, R M; Woodworth, C D; Volkov, D O; Sokolov, Igor
2012-06-01
A significant change of surface features of malignant cervical epithelial cells compared to normal cells has been previously reported. Here, we are studying the question at which progressive stage leading to cervical cancer the surface alteration happens. A non-traditional method to identify malignant cervical epithelial cells in vitro, which is based on physical (in contrast to specific biochemical) labelling of cells with fluorescent silica micron-size beads, is used here to examine cells at progressive stages leading to cervical cancer which include normal epithelial cells, cells infected with human papillomavirus type-16 (HPV-16), cells immortalized by HPV-16, and carcinoma cells. The study shows a statistically significant (at p < 0.01) difference between both immortal and cancer cells and a group consisting of normal and infected. There is no significant difference between normal and infected cells. Immortal cells demonstrate the signal which is closer to cancer cells than to either normal or infected cells. This implies that the cell surface, surface cellular brush changes substantially when cells become immortal. Physical labeling of the cell surface represents a substantial departure from the traditional biochemical labeling methods. The results presented show the potential significance of physical properties of the cell surface for development of clinical methods for early detection of cervical cancer, even at the stage of immortalized, premalignant cells.
Iyer, K. Swaminathan; Gaikwad, R. M.; Woodworth, C. D.; Volkov, D. O.
2013-01-01
A significant change of surface features of malignant cervical epithelial cells compared to normal cells has been previously reported. Here, we are studying the question at which progressive stage leading to cervical cancer the surface alteration happens. A non-traditional method to identify malignant cervical epithelial cells in vitro, which is based on physical (in contrast to specific biochemical) labelling of cells with fluorescent silica micron-size beads, is used here to examine cells at progressive stages leading to cervical cancer which include normal epithelial cells, cells infected with human papillomavirus type-16 (HPV-16), cells immortalized by HPV-16, and carcinoma cells. The study shows a statistically significant (at p <0.01) difference between both immortal and cancer cells and a group consisting of normal and infected. There is no significant difference between normal and infected cells. Immortal cells demonstrate the signal which is closer to cancer cells than to either normal or infected cells. This implies that the cell surface, surface cellular brush changes substantially when cells become immortal. Physical labeling of the cell surface represents a substantial departure from the traditional biochemical labeling methods. The results presented show the potential significance of physical properties of the cell surface for development of clinical methods for early detection of cervical cancer, even at the stage of immortalized, pre-malignant cells. PMID:22351422
Microbiological testing of pharmaceuticals and cosmetics in Egypt.
Zeitoun, Hend; Kassem, Mervat; Raafat, Dina; AbouShlieb, Hamida; Fanaki, Nourhan
2015-12-09
Microbial contamination of pharmaceuticals poses a great problem to the pharmaceutical manufacturing process, especially from a medical as well as an economic point of view. Depending upon the product and its intended use, the identification of isolates should not merely be limited to the United States Pharmacopeia (USP) indicator organisms. Eighty-five pre-used non-sterile pharmaceuticals collected from random consumers in Egypt were examined for the eventual presence of bacterial contaminants. Forty-one bacterial contaminants were isolated from 31 of the tested preparations. These isolates were subjected to biochemical identification by both conventional tests as well as API kits, which were sufficient for the accurate identification of only 11 out of the 41 bacterial contaminants (26.8%) to the species level. The remaining isolates were inconclusively identified or showed contradictory results after using both biochemical methods. Using molecular methods, 24 isolates (58.5%) were successfully identified to the species level. Moreover, polymerase chain reaction (PCR) assays were compared to standard biochemical methods in the detection of pharmacopoeial bacterial indicators in artificially-contaminated pharmaceutical samples. PCR-based methods proved to be superior regarding speed, cost-effectiveness and sensitivity. Therefore, pharmaceutical manufacturers would be advised to adopt PCR-based methods in the microbiological quality testing of pharmaceuticals in the future.
NASA Astrophysics Data System (ADS)
Ginsburg, Shoshana B.; Rusu, Mirabela; Kurhanewicz, John; Madabhushi, Anant
2014-03-01
In this study we explore the ability of a novel machine learning approach, in conjunction with computer-extracted features describing prostate cancer morphology on pre-treatment MRI, to predict whether a patient will develop biochemical recurrence within ten years of radiation therapy. Biochemical recurrence, which is characterized by a rise in serum prostate-specific antigen (PSA) of at least 2 ng/mL above the nadir PSA, is associated with increased risk of metastasis and prostate cancer-related mortality. Currently, risk of biochemical recurrence is predicted by the Kattan nomogram, which incorporates several clinical factors to predict the probability of recurrence-free survival following radiation therapy (but has limited prediction accuracy). Semantic attributes on T2w MRI, such as the presence of extracapsular extension and seminal vesicle invasion and surrogate measure- ments of tumor size, have also been shown to be predictive of biochemical recurrence risk. While the correlation between biochemical recurrence and factors like tumor stage, Gleason grade, and extracapsular spread are well- documented, it is less clear how to predict biochemical recurrence in the absence of extracapsular spread and for small tumors fully contained in the capsule. Computer{extracted texture features, which quantitatively de- scribe tumor micro-architecture and morphology on MRI, have been shown to provide clues about a tumor's aggressiveness. However, while computer{extracted features have been employed for predicting cancer presence and grade, they have not been evaluated in the context of predicting risk of biochemical recurrence. This work seeks to evaluate the role of computer-extracted texture features in predicting risk of biochemical recurrence on a cohort of sixteen patients who underwent pre{treatment 1.5 Tesla (T) T2w MRI. We extract a combination of first-order statistical, gradient, co-occurrence, and Gabor wavelet features from T2w MRI. To identify which of these T2w MRI texture features are potential independent prognostic markers of PSA failure, we implement a partial least squares (PLS) method to embed the data in a low{dimensional space and then use the variable importance in projections (VIP) method to quantify the contributions of individual features to classification on the PLS embedding. In spite of the poor resolution of the 1.5 T MRI data, we are able to identify three Gabor wavelet features that, in conjunction with a logistic regression classifier, yield an area under the receiver operating characteristic curve of 0.83 for predicting the probability of biochemical recurrence following radiation therapy. In comparison to both the Kattan nomogram and semantic MRI attributes, the ability of these three computer-extracted features to predict biochemical recurrence risk is demonstrated.
Biochemical Evolution of Iron and Copper Proteins, Substances Vital to Life
ERIC Educational Resources Information Center
Frieden, Earl
1974-01-01
Summarizes studies in the area of biochemical evolution of iron, copper, and heme proteins to provide an historical outline. Included are lists of major kinds of proteins and enzymes and charts illustrating electron flow in a cytochrome electron transport system and interconversion of jerrous to ferric ion in iron metabolism. (CC)
Biochemical Oxygen Demand and Dissolved Oxygen. Training Module 5.105.2.77.
ERIC Educational Resources Information Center
Kirkwood Community Coll., Cedar Rapids, IA.
This document is an instructional module package prepared in objective form for use by an instructor familiar with the azide modification of the Winkler dissolved oxygen test and the electronic dissolved oxygen meter test procedures for determining the dissolved oxygen and the biochemical oxygen demand of a wastewater sample. Included are…
Nanau, Radu M; Neuman, Manuela G
2015-06-29
The quantitative, measurable detection of drinking is important for the successful treatment of alcohol misuse in transplantation of patients with alcohol disorders, people living with human immunodeficiency virus that need to adhere to medication, and special occupational hazard offenders, many of whom continually deny drinking. Their initial misconduct usually leads to medical problems associated with drinking, impulsive social behavior, and drunk driving. The accurate identification of alcohol consumption via biochemical tests contributes significantly to the monitoring of drinking behavior. A systematic review of the current methods used to measure biomarkers of alcohol consumption was conducted using PubMed and Google Scholar databases (2010-2015). The names of the tests have been identified. The methods and publications that correlate between the social instruments and the biochemical tests were further investigated. There is a clear need for assays standardization to ensure the use of these biochemical tests as routine biomarkers. Alcohol ingestion can be measured using a breath test. Because alcohol is rapidly eliminated from the circulation, the time for detection by this analysis is in the range of hours. Alcohol consumption can alternatively be detected by direct measurement of ethanol concentration in blood or urine. Several markers have been proposed to extend the interval and sensitivities of detection, including ethyl glucuronide and ethyl sulfate in urine, phosphatidylethanol in blood, and ethyl glucuronide and fatty acid ethyl esters in hair, among others. Moreover, there is a need to correlate the indirect biomarker carbohydrate deficient transferrin, which reflects longer lasting consumption of higher amounts of alcohol, with serum γ-glutamyl transpeptidase, another long term indirect biomarker that is routinely used and standardized in laboratory medicine.
Rexford, Alix; Zorio, Diego A R; Miller, Brian G
2017-01-01
The glycolytic enzyme glucokinase (GCK) and the pro-apoptotic protein BAD reportedly reside within a five-membered complex that localizes to the mitochondria of mammalian hepatocytes and pancreatic β-cells. Photochemical crosslinking studies using a synthetic analog of BAD's BH3 domain and in vitro transcription/translation experiments support a direct interaction between BAD and GCK. To investigate the biochemical and biophysical consequences of the BAD:GCK interaction, we developed a method for the production of recombinant human BAD. Consistent with published reports, recombinant BAD displays high affinity for Bcl-xL (KD = 7 nM), and phosphorylation of BAD at S118, within the BH3 domain, abolishes this interaction. Unexpectedly, we do not detect association of recombinant, full-length BAD with recombinant human pancreatic GCK over a range of protein concentrations using various biochemical methods including size-exclusion chromatography, chemical cross-linking, analytical ultracentrifugation, and isothermal titration calorimetry. Furthermore, fluorescence polarization assays and isothermal titration calorimetry detect no direct interaction between GCK and BAD BH3 peptides. Kinetic characterization of GCK in the presence of high concentrations of recombinant BAD show modest (<15%) increases in GCK activity, observable only at glucose concentrations well below the K0.5 value. GCK activity is unaffected by BAD BH3 peptides. These results raise questions as to the mechanism of action of stapled peptide analogs modeled after the BAD BH3 domain, which reportedly enhance the Vmax value of GCK and stimulate insulin release in BAD-deficient islets. Based on our results, we postulate that the BAD:GCK interaction, and any resultant regulatory effect(s) upon GCK activity, requires the participation of additional members of the mitochondrial complex.
Talebi, Malihe; Sadeghi, Javad; Rahimi, Fateh; Pourshafie, Mohammad Reza
2015-04-01
Vancomycin-resistant enterococci (VRE) are important nosocomial pathogens and food chain has been considered as an assumed source for dissemination of VRE to human. The presence of VRE isolates from food samples and typing of these isolates with Phene plate, a biochemical fingerprinting method, were investigated. Thirty samples of meat, chicken and cheese were analyzed for VRE during 2010. Antibiotic susceptibility tests and minimum inhibitory concentration (MIC) were also examined. VRE isolates were typed with the Phene plate system (PhPlate), a biochemical fingerprinting method. A total of 70 VRE isolates were obtained and identified as Enterococcus faecium by species-specific PCR. All the isolates carried vanA, while none of them harbored vanB. The VRE isolates included 35, 27, and 8 isolates from meat, chicken and cheese, respectively. Typing with the PhPlate revealed a diversity index of 0.78 for E. faecium, containing 10 common and four single types. The results of antibiotic susceptibility and MIC tests showed an increased resistance to ciprofloxacin, erythromycin, ampicillin and gentamicin, to which, 100%, 100%, 100%, and 95% of VRE isolates were resistant, respectively. Only 5% of the isolates were resistant to chloramphenicol and the MIC of the isolates for vancomycin and teicoplanin was ≥ 256 µg/mL and for gentamicin-resistant isolates it was 1024 µg/mL. Conventional and molecular identification tests exhibited that all the isolates were E. faecium carrying vanA. None of the isolates harbored vanB. The results showed that enterococci are common contaminants in food. Indeed, this study indicates a high prevalence of multidrug-resistant enterococci in food of animal origin in Iran. Isolating some persisting enterococcal isolates revealed that continuous surveillance of antimicrobial resistance in enterococci from food is essential.
Ozarda, Yesim; Ichihara, Kiyoshi; Aslan, Diler; Aybek, Hulya; Ari, Zeki; Taneli, Fatma; Coker, Canan; Akan, Pinar; Sisman, Ali Riza; Bahceci, Onur; Sezgin, Nurzen; Demir, Meltem; Yucel, Gultekin; Akbas, Halide; Ozdem, Sebahat; Polat, Gurbuz; Erbagci, Ayse Binnur; Orkmez, Mustafa; Mete, Nuriye; Evliyaoglu, Osman; Kiyici, Aysel; Vatansev, Husamettin; Ozturk, Bahadir; Yucel, Dogan; Kayaalp, Damla; Dogan, Kubra; Pinar, Asli; Gurbilek, Mehmet; Cetinkaya, Cigdem Damla; Akin, Okhan; Serdar, Muhittin; Kurt, Ismail; Erdinc, Selda; Kadicesme, Ozgur; Ilhan, Necip; Atali, Dilek Sadak; Bakan, Ebubekir; Polat, Harun; Noyan, Tevfik; Can, Murat; Bedir, Abdulkerim; Okuyucu, Ali; Deger, Orhan; Agac, Suret; Ademoglu, Evin; Kaya, Ayşem; Nogay, Turkan; Eren, Nezaket; Dirican, Melahat; Tuncer, GulOzlem; Aykus, Mehmet; Gunes, Yeliz; Ozmen, Sevda Unalli; Kawano, Reo; Tezcan, Sehavet; Demirpence, Ozlem; Degirmen, Elif
2014-12-01
A nationwide multicenter study was organized to establish reference intervals (RIs) in the Turkish population for 25 commonly tested biochemical analytes and to explore sources of variation in reference values, including regionality. Blood samples were collected nationwide in 28 laboratories from the seven regions (≥400 samples/region, 3066 in all). The sera were collectively analyzed in Uludag University in Bursa using Abbott reagents and analyzer. Reference materials were used for standardization of test results. After secondary exclusion using the latent abnormal values exclusion method, RIs were derived by a parametric method employing the modified Box-Cox formula and compared with the RIs by the non-parametric method. Three-level nested ANOVA was used to evaluate variations among sexes, ages and regions. Associations between test results and age, body mass index (BMI) and region were determined by multiple regression analysis (MRA). By ANOVA, differences of reference values among seven regions were significant in none of the 25 analytes. Significant sex-related and age-related differences were observed for 10 and seven analytes, respectively. MRA revealed BMI-related changes in results for uric acid, glucose, triglycerides, high-density lipoprotein (HDL)-cholesterol, alanine aminotransferase, and γ-glutamyltransferase. Their RIs were thus derived by applying stricter criteria excluding individuals with BMI >28 kg/m2. Ranges of RIs by non-parametric method were wider than those by parametric method especially for those analytes affected by BMI. With the lack of regional differences and the well-standardized status of test results, the RIs derived from this nationwide study can be used for the entire Turkish population.
Shamloo, Amir; Mohammadaliha, Negar; Mohseni, Mina
2015-10-20
This review aims to propose the integrative implementation of microfluidic devices, biomaterials, and computational methods that can lead to a significant progress in tissue engineering and regenerative medicine researches. Simultaneous implementation of multiple techniques can be very helpful in addressing biological processes. Providing controllable biochemical and biomechanical cues within artificial extracellular matrix similar to in vivo conditions is crucial in tissue engineering and regenerative medicine researches. Microfluidic devices provide precise spatial and temporal control over cell microenvironment. Moreover, generation of accurate and controllable spatial and temporal gradients of biochemical factors is attainable inside microdevices. Since biomaterials with tunable properties are a worthwhile option to construct artificial extracellular matrix, in vitro platforms that simultaneously utilize natural, synthetic, or engineered biomaterials inside microfluidic devices are phenomenally advantageous to experimental studies in the field of tissue engineering. Additionally, collaboration between experimental and computational methods is a useful way to predict and understand mechanisms responsible for complex biological phenomena. Computational results can be verified by using experimental platforms. Computational methods can also broaden the understanding of the mechanisms behind the biological phenomena observed during experiments. Furthermore, computational methods are powerful tools to optimize the fabrication of microfluidic devices and biomaterials with specific features. Here we present a succinct review of the benefits of microfluidic devices, biomaterial, and computational methods in the case of tissue engineering and regeneration medicine. Furthermore, some breakthroughs in biological phenomena including the neuronal axon development, cancerous cell migration and blood vessel formation via angiogenesis by virtue of the aforementioned approaches are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.
Schiebel, Johannes; Radeva, Nedyalka; Köster, Helene; Metz, Alexander; Krotzky, Timo; Kuhnert, Maren; Diederich, Wibke E; Heine, Andreas; Neumann, Lars; Atmanene, Cedric; Roecklin, Dominique; Vivat-Hannah, Valérie; Renaud, Jean-Paul; Meinecke, Robert; Schlinck, Nina; Sitte, Astrid; Popp, Franziska; Zeeb, Markus; Klebe, Gerhard
2015-09-01
Fragment-based lead discovery is gaining momentum in drug development. Typically, a hierarchical cascade of several screening techniques is consulted to identify fragment hits which are then analyzed by crystallography. Because crystal structures with bound fragments are essential for the subsequent hit-to-lead-to-drug optimization, the screening process should distinguish reliably between binders and non-binders. We therefore investigated whether different screening methods would reveal similar collections of putative binders. First we used a biochemical assay to identify fragments that bind to endothiapepsin, a surrogate for disease-relevant aspartic proteases. In a comprehensive screening approach, we then evaluated our 361-entry library by using a reporter-displacement assay, saturation-transfer difference NMR, native mass spectrometry, thermophoresis, and a thermal shift assay. While the combined results of these screening methods retrieve 10 of the 11 crystal structures originally predicted by the biochemical assay, the mutual overlap of individual hit lists is surprisingly low, highlighting that each technique operates on different biophysical principles and conditions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Biochemical phenotypes to discriminate microbial subpopulations and improve outbreak detection.
Galar, Alicia; Kulldorff, Martin; Rudnick, Wallis; O'Brien, Thomas F; Stelling, John
2013-01-01
Clinical microbiology laboratories worldwide constitute an invaluable resource for monitoring emerging threats and the spread of antimicrobial resistance. We studied the growing number of biochemical tests routinely performed on clinical isolates to explore their value as epidemiological markers. Microbiology laboratory results from January 2009 through December 2011 from a 793-bed hospital stored in WHONET were examined. Variables included patient location, collection date, organism, and 47 biochemical and 17 antimicrobial susceptibility test results reported by Vitek 2. To identify biochemical tests that were particularly valuable (stable with repeat testing, but good variability across the species) or problematic (inconsistent results with repeat testing), three types of variance analyses were performed on isolates of K. pneumonia: descriptive analysis of discordant biochemical results in same-day isolates, an average within-patient variance index, and generalized linear mixed model variance component analysis. 4,200 isolates of K. pneumoniae were identified from 2,485 patients, 32% of whom had multiple isolates. The first two variance analyses highlighted SUCT, TyrA, GlyA, and GGT as "nuisance" biochemicals for which discordant within-patient test results impacted a high proportion of patient results, while dTAG had relatively good within-patient stability with good heterogeneity across the species. Variance component analyses confirmed the relative stability of dTAG, and identified additional biochemicals such as PHOS with a large between patient to within patient variance ratio. A reduced subset of biochemicals improved the robustness of strain definition for carbapenem-resistant K. pneumoniae. Surveillance analyses suggest that the reduced biochemical profile could improve the timeliness and specificity of outbreak detection algorithms. The statistical approaches explored can improve the robust recognition of microbial subpopulations with routinely available biochemical test results, of value in the timely detection of outbreak clones and evolutionarily important genetic events.
Ray, Sayantan; Khanra, Dibbendhu; Sonthalia, Nikhil; Kundu, Supratip; Biswas, Kaushik; Talukdar, Arunansu; Saha, Manjari; Bera, Himel
2014-10-01
Alcoholism is a health problem not only in developed countries but also in developing countries. Cirrhosis due to alcohol is a common cause of death among individuals abusing alcohol. A better knowledge of the spectrum of alcoholic liver diseases, its clinical, biochemical and histopathological features could result in early detection and prevention of alcoholic liver diseases before it's catastrophic and life threatening effects. A total of 200 patients with alcoholic liver diseases were studied with respect to alcohol consumption, clinical features, biochemical and histopathological changes. The clinical features, biochemical parameters, and histopathology of liver including Ishak's modified histological activity index (HAI) were correlated with the amount and duration of alcohol consumed. Majority of the patients were in the age group of 40-49 years and all the cases were males. Majority consumed alcohol of about 75-90 grams per day for a duration of 10-12 years. Anorexia and jaundice were the most common symptom and clinical finding respectively. Hyperbilirubinemia and hypoalbuminemia were the most common abnormalities observed in liver function tests. Advanced HAI stages with features of cirrhosis were most frequent histo-pathological finding noted in this study. Clinico-biochemical profile was significantly correlated with degree of alcohol ingestion as well as with liver histopathology. The wide prevalence of alcoholic liver disease including cirrhosis among Indian males was noted with significantly lower quantity and duration of alcohol ingestion. The severity of liver damage is directly proportional to the quantity and duration of alcohol consumed. Clinical features and biochemical changes may forecast the liver histopathology among the patients of alcoholic liver disease.
A moment-convergence method for stochastic analysis of biochemical reaction networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Jiajun; Nie, Qing; Zhou, Tianshou, E-mail: mcszhtsh@mail.sysu.edu.cn
Traditional moment-closure methods need to assume that high-order cumulants of a probability distribution approximate to zero. However, this strong assumption is not satisfied for many biochemical reaction networks. Here, we introduce convergent moments (defined in mathematics as the coefficients in the Taylor expansion of the probability-generating function at some point) to overcome this drawback of the moment-closure methods. As such, we develop a new analysis method for stochastic chemical kinetics. This method provides an accurate approximation for the master probability equation (MPE). In particular, the connection between low-order convergent moments and rate constants can be more easily derived in termsmore » of explicit and analytical forms, allowing insights that would be difficult to obtain through direct simulation or manipulation of the MPE. In addition, it provides an accurate and efficient way to compute steady-state or transient probability distribution, avoiding the algorithmic difficulty associated with stiffness of the MPE due to large differences in sizes of rate constants. Applications of the method to several systems reveal nontrivial stochastic mechanisms of gene expression dynamics, e.g., intrinsic fluctuations can induce transient bimodality and amplify transient signals, and slow switching between promoter states can increase fluctuations in spatially heterogeneous signals. The overall approach has broad applications in modeling, analysis, and computation of complex biochemical networks with intrinsic noise.« less
AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide
2015-11-19
Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database in which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. This database will facilitate the analysis of protein-DNA interactions and the development of programmatic computational methods that capitalize on integration of structural and biochemical datasets. The database can be accessed at http://ProteinDNA.hms.harvard.edu.
PENN Biomarker Core of the Alzheimer’s Disease Neuroimaging Initiative
Shaw, Leslie M.
2009-01-01
There is a pressing need to develop effective prevention and disease-modifying treatments for Alzheimer’s disease (AD), a dreaded affliction whose incidence increases almost logarithmically with age starting at about 65 years. A key need in the field of AD research is the validation of imaging and biochemical biomarkers. Biomarker tests that are shown to reliably predict the disease before it is clinically expressed would permit testing of new therapeutics at the earliest time point possible in order to give the best chance for delaying the onset of dementia in these patients. In this review the current state of AD biochemical biomarker research is discussed. A new set of guidelines for the diagnosis of AD in the research setting places emphasis on the inclusion of selected imaging and biochemical biomarkers, in addition to neuropsychological behavioral testing. Importantly, the revised guidelines were developed to identify patients at the earliest stages prior to full-blown dementia as well as patients with the full spectrum of the disease. The Alzheimer’s Disease Neuroimaging Initiative is a multicenter consortium study that includes as one of its primary goals the development of standardized neuroimaging and biochemical biomarker methods for AD clinical trials, as well as using these to measure changes over time in mildly cognitively impaired patients who convert to AD as compared to the natural variability of these in control subjects and their further change over time in AD patients. Validation of the biomarker results by correlation analyses with neuropsychological and neurobehavioral test data is one of the primary outcomes of this study. This validation data will hopefully provide biomarker test performance needed for effective measurement of the efficacy of new treatment and prevention therapeutic agents. PMID:18097156
Rossi, Peter J; Urbanic, James; Clark, Peter E; McCullough, David L; Lee, W Robert
2008-01-01
This report examines the relationship between pretreatment prostate-specific antigen (PSA) velocity (PSAV) and freedom from biochemical recurrence (FFBR) in men with prostate cancer treated with low-dose-rate prostate brachytherapy (LDRPB). This is a report of 51 men treated with LDRPB between 1997 and 1999. two or more evaluable PSA values >3 months apart and <18 months before treatment. PSAV is calculated using a linear regression equation. All patients had biopsy confirmed, clinically localized prostate cancer. All men were treated with (125)I LDRPB. The prescription dose was 144Gy. Biochemical failure is determined from PSA values over time using the ASTRO Consensus Definition. FFBR is estimated using Kaplan-Meier method. Pretreatment variables analyzed include percentage positive biopsy cores, D(90), risk group, and PSAV. All p values are two-sided. The median followup is 60 months. The median pretreatment PSA is 6.5, 75% of men were Stage T1c, and 88% had Gleason score > or =6; 10% developed evidence of biochemical recurrence at a median of 13 months (range, 6-36). The 6-year estimate of FFBR is 90% for the entire cohort. On univariate analysis, pretreatment PSAV and risk group are associated with FFBR. The 6-year estimate of FFBR in patients with a PSAV <2 ng/mL/yr is 100% vs. 80% (95% confidence interval: 64-96%) when the pretreatment PSAV is > or =2 ng/mL/yr before LDRPB (p = 0.017). Pretreatment PSAV is a predictor of FFBR after LDRPB in this population of men with prostate cancer. Men with a pretreatment PSAV > or =2 ng/mL/yr may warrant more aggressive treatment.
Predicting Infected Bile Among Patients Undergoing Percutaneous Cholecystostomy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beardsley, Shannon L.; Shlansky-Goldberg, Richard D.; Patel, Aalpen
2005-04-15
Purpose. Patients may not achieve a clinical benefit after percutaneous cholecystostomy due to the inherent difficulty in identifying patients who truly have infected gallbladders. We attempted to identify imaging and biochemical parameters which would help to predict which patients have infected gallbladders. Methods. A retrospective review was performed of 52 patients undergoing percutaneous cholecystostomy for clinical suspicion of acute cholecystitis in whom bile culture results were available. Multiple imaging and biochemical variables were examined alone and in combination as predictors of infected bile, using logistic regression. Results. Of the 52 patients, 25 (48%) had infected bile. Organisms cultured included Enterococcus,more » Enterobacter, Klebsiella, Pseudomonas, E. coli, Citrobacter and Candida. No biochemical parameters were significantly predictive of infected bile; white blood cell count >15,000 was weakly associated with greater odds of infected bile (odds ratio 2.0, p = NS). The presence of gallstones, sludge, gallbladder wall thickening and pericholecystic fluid by ultrasound or CT were not predictive of infected bile, alone or in combination, although a trend was observed among patients with CT findings of acute cholecystitis toward a higher 30-day mortality. Radionuclide scans were performed in 31% of patients; all were positive and 66% of these patients had infected bile. Since no patient who underwent a radionuclide scan had a negative study, this variable could not be entered into the regression model due to collinearity. Conclusion. No single CT or ultrasound imaging variable was predictive of infected bile, and only a weak association of white blood cell count with infected bile was seen. No other biochemical parameters had any association with infected bile. The ability of radionuclide scanning to predict infected bile was higher than that of ultrasound or CT. This study illustrates the continued challenge to identify bacterial cholecystitis among patients referred for percutaneous cholecystostomy.« less
Osna, Natalia A; Feng, Dan; Ganesan, Murali; Maillacheruvu, Priya F; Orlicky, David J; French, Samuel W; Tuma, Dean J; Kharbanda, Kusum K
2016-01-01
AIM To investigate the hypothesis that exposure to guanidinoacetate (GAA, a potent methyl-group consumer) either alone or combined with ethanol intake for a prolonged period of time would cause more advanced liver pathology thus identifying methylation defects as the initiator and stimulator for progressive liver damage. METHODS Adult male Wistar rats were fed the control or ethanol Lieber DeCarli diet in the absence or presence of GAA supplementation. At the end of 6 wk of the feeding regimen, various biochemical and histological analyses were conducted. RESULTS Contrary to our expectations, we observed that GAA treatment alone resulted in a histologically normal liver without evidence of hepatosteatosis despite persistence of some abnormal biochemical parameters. This protection could result from the generation of creatine from the ingested GAA. Ethanol treatment for 6 wk exhibited changes in liver methionine metabolism and persistence of histological and biochemical defects as reported before. Further, when the rats were fed the GAA-supplemented ethanol diet, similar histological and biochemical changes as observed after 2 wk of combined treatment, including inflammation, macro- and micro-vesicular steatosis and a marked decrease in the methylation index were noted. In addition, rats on the combined treatment exhibited increased liver toxicity and even early fibrotic changes in a subset of animals in this group. The worsening liver pathology could be related to the profound reduction in the hepatic methylation index, an increased accumulation of GAA and the inability of creatine generated to exert its hepato-protective effects in the setting of ethanol. CONCLUSION To conclude, prolonged exposure to a methyl consumer superimposed on chronic ethanol consumption causes persistent and pronounced liver damage. PMID:27784962
Artificial enzymes with protein scaffolds: structural design and modification.
Matsuo, Takashi; Hirota, Shun
2014-10-15
Recent development in biochemical experiment techniques and bioinformatics has enabled us to create a variety of artificial biocatalysts with protein scaffolds (namely 'artificial enzymes'). The construction methods of these catalysts include genetic mutation, chemical modification using synthetic molecules and/or a combination of these methods. Designed evolution strategy based on the structural information of host proteins has become more and more popular as an effective approach to construct artificial protein-based biocatalysts with desired reactivities. From the viewpoint of application of artificial enzymes for organic synthesis, recently constructed artificial enzymes mediating oxidation, reduction and C-C bond formation/cleavage are introduced in this review article. Copyright © 2014 Elsevier Ltd. All rights reserved.
Heuett, William J; Beard, Daniel A; Qian, Hong
2008-05-15
Several approaches, including metabolic control analysis (MCA), flux balance analysis (FBA), correlation metric construction (CMC), and biochemical circuit theory (BCT), have been developed for the quantitative analysis of complex biochemical networks. Here, we present a comprehensive theory of linear analysis for nonequilibrium steady-state (NESS) biochemical reaction networks that unites these disparate approaches in a common mathematical framework and thermodynamic basis. In this theory a number of relationships between key matrices are introduced: the matrix A obtained in the standard, linear-dynamic-stability analysis of the steady-state can be decomposed as A = SRT where R and S are directly related to the elasticity-coefficient matrix for the fluxes and chemical potentials in MCA, respectively; the control-coefficients for the fluxes and chemical potentials can be written in terms of RTBS and STBS respectively where matrix B is the inverse of A; the matrix S is precisely the stoichiometric matrix in FBA; and the matrix eAt plays a central role in CMC. One key finding that emerges from this analysis is that the well-known summation theorems in MCA take different forms depending on whether metabolic steady-state is maintained by flux injection or concentration clamping. We demonstrate that if rate-limiting steps exist in a biochemical pathway, they are the steps with smallest biochemical conductances and largest flux control-coefficients. We hypothesize that biochemical networks for cellular signaling have a different strategy for minimizing energy waste and being efficient than do biochemical networks for biosynthesis. We also discuss the intimate relationship between MCA and biochemical systems analysis (BSA).
Biochemical responses of the Skylab crewman
NASA Technical Reports Server (NTRS)
Leach, C. S.; Rambaut, P. C.
1974-01-01
The biochemical investigations of the Skylab crewmen were designed to study the physiological changes that were observed on flight crews returning from previous space flight missions as well as to study those changes expected to result from prolonged weightless exposure. These studies can be divided into two broad categories. One category included routine blood studies similar to those used in clinical medical practice. The second included research-type endocrine analyses used to investigate more thoroughly the metabolic/endocrine responses to the space flight environment. The premission control values indicated that all Skylab crewmen were healthy and were free from biochemical abnormalities. The routine results during and after flight showed slight but significant changes in electrolytes, glucose, total protein, osmolality, uric acid, cholesterol, and creatinine. Plasma hormal changes included adrenocorticotrophic hormone, cortisol, angiotensin I, aldosterone, insulin, and thyroxine. The 24-hour urine analyses results revealed increased excretion of cortisol, catecholamines, antidiuretic hormone, and aldosterone as well as excretion of significant electrolyte and uric acid during the Skylab flights.
ERIC Educational Resources Information Center
Riehl, Matthew
2012-01-01
A graphical method for determining the 5-day biochemical oxygen demand (BOD5) for a body of water is described. In this bioassay, students collect a sample of water from a designated site, transport it to the laboratory, and evaluate the amount of oxygen consumed by naturally occurring bacteria during a 5-day incubation period. An accuracy check,…
Saravanan, A. V.; Ravishankar, P. L.; Kumar, Pradeep; Rajapandian, K.; Kalaivani, V.; Rajula, M. Prem Blaisie
2017-01-01
Aim: The present study was conducted to evaluate the serum triglycerides, serum cholesterol, total protein, and IgG levels in elderly patients who were affected by periodontal disease. Materials and Methods: This study was conducted at the Rajah Muthiah Dental College and Hospital in the periodontics division. The study was conducted for a period of 3 months. This study is a prospective analytical study. Sixty individuals who were systemically healthy in the age group of 50 and above were included in this study. Control and experimental groups of 30 participants each were included. Plaque index, gingival index, probing pocket depth, and clinical attachment loss were recorded. Biochemical parameters such as serum cholesterol, serum triglycerides, total protein, and IgG levels were also evaluated and correlated with the periodontal parameters. Data was analyzed using SPSS version 16.0 (IBM Corp., Armonk, NY). The relationship between periodontal status and the biochemical parameters such as serum cholesterol, serum triglycerides, total protein, and IgG levels were evaluated by Student's t-test. Results: There was no significant difference in the plaque and gingival scores between the experimental and control group. It was observed that serum cholesterol level and total protein level was lower in participants suffering from chronic periodontitis. Triglycerides level was significantly elevated in the experimental group. IgG, a level which is not significant, concluded that there is no difference in control and experimental group. Conclusion: It was concluded from the results obtained from the study that there is an association between serum triglycerides, serum cholesterol, total protein, and periodontal disease. However, further longitudinal and well-controlled studies are required to evaluate the relationship between these biochemical parameters and periodontal disease. PMID:28462181
Baseline hematology and serum biochemistry results for Indian leopards (Panthera pardus fusca)
Shanmugam, Arun Attur; Muliya, Sanath Krishna; Deshmukh, Ajay; Suresh, Sujay; Nath, Anukul; Kalaignan, Pa; Venkataravanappa, Manjunath; Jose, Lyju
2017-01-01
Aim: The aim of the study was to establish the baseline hematology and serum biochemistry values for Indian leopards (Panthera pardus fusca), and to assess the possible variations in these parameters based on age and gender. Materials and Methods: Hemato-biochemical test reports from a total of 83 healthy leopards, carried out as part of routine health evaluation in Bannerghatta Biological Park and Manikdoh Leopard Rescue Center, were used to establish baseline hematology and serum biochemistry parameters for the subspecies. The hematological parameters considered for the analysis included hemoglobin (Hb), packed cell volume, total erythrocyte count (TEC), total leukocyte count (TLC), mean corpuscular volume (MCV), mean corpuscular Hb (MCH), and MCH concentration. The serum biochemistry parameters considered included total protein (TP), albumin, globulin, aspartate aminotransferase, alanine aminotransferase (ALT), blood urea nitrogen, creatinine, triglycerides, calcium, and phosphorus. Results: Even though few differences were observed in hematologic and biochemistry values between male and female Indian leopards, the differences were statistically not significant. Effects of age, however, were evident in relation to many hematologic and biochemical parameters. Sub-adults had significantly greater values for Hb, TEC, and TLC compared to adults and geriatric group, whereas they had significantly lower MCV and MCH compared to adults and geriatric group. Among, serum biochemistry parameters the sub-adult age group was observed to have significantly lower values for TP and ALT than adult and geriatric leopards. Conclusion: The study provides a comprehensive analysis of hematologic and biochemical parameters for Indian leopards. Baselines established here will permit better captive management of the subspecies, serve as a guide to assess the health and physiological status of the free ranging leopards, and may contribute valuable information for making effective management decisions during translocation or rehabilitation process. PMID:28831229
Optimal Information Processing in Biochemical Networks
NASA Astrophysics Data System (ADS)
Wiggins, Chris
2012-02-01
A variety of experimental results over the past decades provide examples of near-optimal information processing in biological networks, including in biochemical and transcriptional regulatory networks. Computing information-theoretic quantities requires first choosing or computing the joint probability distribution describing multiple nodes in such a network --- for example, representing the probability distribution of finding an integer copy number of each of two interacting reactants or gene products while respecting the `intrinsic' small copy number noise constraining information transmission at the scale of the cell. I'll given an overview of some recent analytic and numerical work facilitating calculation of such joint distributions and the associated information, which in turn makes possible numerical optimization of information flow in models of noisy regulatory and biochemical networks. Illustrating cases include quantification of form-function relations, ideal design of regulatory cascades, and response to oscillatory driving.
[Mitochondrial diseases in children including Leigh syndrome--biochemical and molecular background].
Pronicka, Ewa; Piekutowska-Abramczuk, Dorota; Pronicki, Maciej
2008-01-01
Mitochondrial diseases in children are more frequently caused by mutations in nuclear DNA then in mtDNA. Special clinical phenotypes are associated with the mutations in SURF1 gene, in SCO2 gene and with mtDNA depletion syndromes. Leigh syndrome is the most common clinical presentation of various mitochondrial disorders during childhood. Elevation of lactate in blood, cerebrospinal fluid and urine is a simple biochemical marker of mitochondrial disorders but its specificity and sensitivity are low. Biochemical investigation of muscle biopsy and search for mitochondrial mutations remain a gold standard in the diagnosis. The standarized diagnostic criteria to establish level of diagnostic certainty (possible, probable, definite) are proposed to be used in practice; these include clinical features, neuroimaging and muscle biopsy investigations. Further research directions to improve our understanding of mitochondrial pathologies in children are suggested.
Nakonieczna-Rudnicka, Marta; Bachanek, Teresa; Rogowska, Wanda
2009-01-01
Dental decay is a pathological process of extrasomatic origin which leads to demineralization and proteolytic degradation of hard surfaces of a tooth susceptible to this disease. Saliva composition, including calcium ion concentration and its pH value, is of importance in the development of the carious process. Tobacco smoke contains toxic compounds which negatively influence oral health. The aim of the study was evaluation of the selected saliva components: protein concentration, Ca2+ concentration, pH value both in male and female smokers. The investigated group included 65 patients reporting for the treatment to the Department of Conservative Dentistry of Medical University in Lublin. In the investigated group male smokers constituted 15.38%, female smokers--20.00%, male nicotine abstinents 21.54% and female nicotine abstinent 43.08%. The study included both survey examinations of patients and biochemical examinations of the saliva. Mixed, non-stimulated saliva was used as a material for biochemical examinations. Ca2+ concentration and pH of the saliva were assayed with the use of Rapidlab 348 analyzer. Protein in the saliva was assayed with calorimetric method according to Lowry. Saliva was collected from smokers 10-120 minutes after smoking of several cigarettes. It was stated that Ca2+ and protein concentration as well as pH of the saliva were not correlated with sex and cigarette smoking or non-smoking.
2014-01-01
Background The purpose of this study was to compare two biochemical markers, which have been previously used to determine the degrees of alveolar bone destruction, in evaluating periodontal disease severity. Methods The WF6 epitope of chondroitin sulfate (CS) and the alkaline phosphatase (ALP) levels were determined in gingival crevicular fluid (GCF) samples collected from patients with various degrees of disease severity, including ten patients with gingivitis (50 gingivitis sites) and 33 patients with chronic periodontitis (including gingivitis, slight, moderate, and severe periodontitis sites; n = 50 each), as well as from ten healthy volunteers (50 healthy sites) by Periopaper strips. The levels of CS and ALP were measured by an ELISA and a fluorometric assay, respectively. Results The results demonstrated low levels of CS and ALP in non-destructive and slightly destructive periodontitis sites, whereas significantly high levels of these two biomolecules were shown in moderately and severely destructive sites (p < 0.05). Although a significant difference in CS levels was found between moderate and severe periodontitis sites, no difference in ALP levels was found. Stronger correlations were found between CS levels and periodontal parameters, including probing depth, loss of clinical attachment levels, gingival index and plaque index, than between ALP levels and these parameters. Conclusions It is suggested that the CS level is a better diagnostic marker than the ALP level for evaluating distinct severity of chronic periodontitis. PMID:25174345
TRPC Channel Structure and Properties.
Feng, Shengjie
2017-01-01
TRPC channels are the first identified members in the TRP family. They function as either homo- or heterotetramers regulating intracellular Ca 2+ concentration in response to numerous physiological or pathological stimuli. TRPC channels are nonselective cation channels permeable to Ca 2+ . The properties and the functional domains of TRPC channels have been identified by electrophysiological and biochemical methods. However, due to the large size, instability, and flexibility of their complexes, the structures of the members in TRPC family remain unrevealed. More efforts should be made on structure analysis and generating good tools, including specific antibodies, agonist, and antagonist.
Markers of Developmentally Regulated Programmed Cell Death and Their Analysis in Cereal Seeds.
Domínguez, Fernando; Cejudo, Francisco Javier
2018-01-01
Programmed cell death (PCD) is a key process for the development and differentiation of multicellular organisms, which is characterized by well-defined morphological and biochemical features. These include chromatin condensation, DNA degradation and nuclear fragmentation, with nucleases and proteases playing a relevant function in these processes. In this chapter we describe methods routinely used for the analysis of hallmarks of developmentally regulated PCD in cereal seed tissues, which are based on agarose and polyacrylamide gel electrophoresis, in situ staining of DNA fragmentation, and cell-free assays of relevant enzymatic activities.
The role of networks and artificial intelligence in nanotechnology design and analysis.
Hudson, D L; Cohen, M E
2004-05-01
Techniques with their origins in artificial intelligence have had a great impact on many areas of biomedicine. Expert-based systems have been used to develop computer-assisted decision aids. Neural networks have been used extensively in disease classification and more recently in many bioinformatics applications including genomics and drug design. Network theory in general has proved useful in modeling all aspects of biomedicine from healthcare organizational structure to biochemical pathways. These methods show promise in applications involving nanotechnology both in the design phase and in interpretation of system functioning.
Hadadi, Noushin; Hafner, Jasmin; Shajkofci, Adrian; Zisaki, Aikaterini; Hatzimanikatis, Vassily
2016-10-21
Because the complexity of metabolism cannot be intuitively understood or analyzed, computational methods are indispensable for studying biochemistry and deepening our understanding of cellular metabolism to promote new discoveries. We used the computational framework BNICE.ch along with cheminformatic tools to assemble the whole theoretical reactome from the known metabolome through expansion of the known biochemistry presented in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. We constructed the ATLAS of Biochemistry, a database of all theoretical biochemical reactions based on known biochemical principles and compounds. ATLAS includes more than 130 000 hypothetical enzymatic reactions that connect two or more KEGG metabolites through novel enzymatic reactions that have never been reported to occur in living organisms. Moreover, ATLAS reactions integrate 42% of KEGG metabolites that are not currently present in any KEGG reaction into one or more novel enzymatic reactions. The generated repository of information is organized in a Web-based database ( http://lcsb-databases.epfl.ch/atlas/ ) that allows the user to search for all possible routes from any substrate compound to any product. The resulting pathways involve known and novel enzymatic steps that may indicate unidentified enzymatic activities and provide potential targets for protein engineering. Our approach of introducing novel biochemistry into pathway design and associated databases will be important for synthetic biology and metabolic engineering.
Tendon and ligament as novel cell sources for engineering the knee meniscus
Hadidi, Pasha; Paschos, Nikolaos K.; Huang, Brian J.; Aryaei, Ashkan; Hu, Jerry C.; Athanasiou, Kyriacos A.
2016-01-01
Objective The application of cell-based therapies in regenerative medicine is hindered by the difficulty of acquiring adequate numbers of competent cells. For the knee meniscus in particular, this may be solved by harvesting tissue from neighboring tendons and ligaments. In this study, we have investigated the potential of cells from tendon and ligament, as compared to meniscus cells, to engineer scaffold-free self-assembling fibrocartilage. Method Self-assembling meniscus-shaped constructs engineered from a co-culture of articular chondrocytes and either meniscus, tendon, or ligament cells were cultured for 4 weeks with TGF-β1 in serum-free media. After culture, constructs were assessed for their mechanical properties, histological staining, gross appearance, and biochemical composition including cross-link content. Correlations were performed to evaluate relationships between biochemical content and mechanical properties. Results In terms of mechanical properties as well as biochemical content, constructs engineered using tenocytes and ligament fibrocytes were found to be equivalent or superior to constructs engineered using meniscus cells. Furthermore, cross-link content was found to be correlated with engineered tissue tensile properties. Conclusion Tenocytes and ligament fibrocytes represent viable cell sources for engineering meniscus fibrocartilage using the self-assembling process. Due to greater cross-link content, fibrocartilage engineered with tenocytes and ligament fibrocytes may maintain greater tensile properties than fibrocartilage engineered with meniscus cells. PMID:27473559
Hybrid ODE/SSA methods and the cell cycle model
NASA Astrophysics Data System (ADS)
Wang, S.; Chen, M.; Cao, Y.
2017-07-01
Stochastic effect in cellular systems has been an important topic in systems biology. Stochastic modeling and simulation methods are important tools to study stochastic effect. Given the low efficiency of stochastic simulation algorithms, the hybrid method, which combines an ordinary differential equation (ODE) system with a stochastic chemically reacting system, shows its unique advantages in the modeling and simulation of biochemical systems. The efficiency of hybrid method is usually limited by reactions in the stochastic subsystem, which are modeled and simulated using Gillespie's framework and frequently interrupt the integration of the ODE subsystem. In this paper we develop an efficient implementation approach for the hybrid method coupled with traditional ODE solvers. We also compare the efficiency of hybrid methods with three widely used ODE solvers RADAU5, DASSL, and DLSODAR. Numerical experiments with three biochemical models are presented. A detailed discussion is presented for the performances of three ODE solvers.
Yao, Xiaoqin; Chu, Jian-Zhou; Ma, Chun-Hui; Si, Chao; Li, Ji-Gang; Shi, Xiao-Fei; Liu, Chao-Nan
2015-08-01
The article studied UV-B effects on biochemical traits and proteomic changes in postharvest flowers of medicinal chrysanthemum. The experiment about UV-B effects on biochemical traits in flowers included six levels of UV-B treatments (0 (UV0), 50 (UV50), 200 (UV200), 400 (UV400), 600 (UV600) and 800 (UV800) μWcm(-2)). UV400, UV600 and UV800 treatments significantly increased the contents of hydrogen peroxide, malondialdehyde and UV-B absorbing compounds, and the activity of phenylalanine ammonia lyase enzyme over the control. The contents of chlorogenic acid and flavone in flowers were significantly increased by UV-B treatments (except for UV50 and UV800). Two-dimensional gel electrophoresis was utilized to analyze proteomic changes in flowers with or without UV-B radiation. Results indicated that 43 protein spots (>1.5-fold difference in volume) were detected, including 19 spots with a decreasing trend and 24 spots with an increasing trend, and 19 differentially expressed protein spots were successfully indentified by MALDI-TOF MS. The indentified proteins were classified based on functions, the most of which were involved in photosynthesis, respiration, protein biosynthesis and degradation and defence. An overall assessment using biochemical and differential proteomic data revealed that UV-B radiation could affect biochemical reaction and promote secondary metabolism processes in postharvest flowers. Copyright © 2015 Elsevier B.V. All rights reserved.
Biochemistry of homologous recombination in Escherichia coli.
Kowalczykowski, S C; Dixon, D A; Eggleston, A K; Lauder, S D; Rehrauer, W M
1994-01-01
Homologous recombination is a fundamental biological process. Biochemical understanding of this process is most advanced for Escherichia coli. At least 25 gene products are involved in promoting genetic exchange. At present, this includes the RecA, RecBCD (exonuclease V), RecE (exonuclease VIII), RecF, RecG, RecJ, RecN, RecOR, RecQ, RecT, RuvAB, RuvC, SbcCD, and SSB proteins, as well as DNA polymerase I, DNA gyrase, DNA topoisomerase I, DNA ligase, and DNA helicases. The activities displayed by these enzymes include homologous DNA pairing and strand exchange, helicase, branch migration, Holliday junction binding and cleavage, nuclease, ATPase, topoisomerase, DNA binding, ATP binding, polymerase, and ligase, and, collectively, they define biochemical events that are essential for efficient recombination. In addition to these needed proteins, a cis-acting recombination hot spot known as Chi (chi: 5'-GCTGGTGG-3') plays a crucial regulatory function. The biochemical steps that comprise homologous recombination can be formally divided into four parts: (i) processing of DNA molecules into suitable recombination substrates, (ii) homologous pairing of the DNA partners and the exchange of DNA strands, (iii) extension of the nascent DNA heteroduplex; and (iv) resolution of the resulting crossover structure. This review focuses on the biochemical mechanisms underlying these steps, with particular emphases on the activities of the proteins involved and on the integration of these activities into likely biochemical pathways for recombination. Images PMID:7968921
Applicability of ambient toxicity testing to national or regional water-quality assessment
Elder, J.F.
1989-01-01
Comprehensive assessment of the quality of natural waters requires a multifaceted approach. Based on experimentation designed to monitor responses of organisms to environmental stresses, toxicity testing may have diverse purposes in water quality assessments. These purposes may include identification that warrant further study because of poor water quality or unusual ecological features, verification of other types of monitoring, or assessment of contaminant effects on aquatic communities. A wide variety of toxicity test methods have been developed to fulfill the needs of diverse applications. The methods differ primarily in the full selections made relative to four characteristics: (1) test species, (2) endpoints (acute or chronic), (3) test enclosure type, and (4) test substance (toxicant) that functions as the environmental stress. Toxicity test approachs vary in their capacity to meet the needs of large-scale assessments of existing water quality. Ambient testing is more likely to meet these needs than are the procedures that call for exposure of the test organisms to known concentrations of a single toxicant. However, meaningful interpretation of ambient test results depend on the existence of accompanying chemical analysis of the ambient media. The ambient test substance may be water or sediments. Sediment tests have had limited application, but they are useful because of the fact that most toxicants tend to accumulate in sediments, and many test species either inhabit the sediments or are in frequent contact with them. Biochemical testing methods, which have been developing rapidly in recent years, are likely to be among the most useful procedures for large-scale water quality assessments. They are relatively rapid and simple, and more importantly, they focus on biochemical changes that are the initial responses of virtually all organisms to environmental stimuli. Most species are sensitive to relatively few toxicants and their sensitivities vary as conditions change. One of the most informative approaches for toxicity testing is to combine biochemical tests with other test methods in a ' battery or tests ' that is diversified enough to characterize different types of toxicants and different trophic levels. (Lantz-PTT)
Quantitative evaluation methods of skin condition based on texture feature parameters.
Pang, Hui; Chen, Tianhua; Wang, Xiaoyi; Chang, Zhineng; Shao, Siqi; Zhao, Jing
2017-03-01
In order to quantitatively evaluate the improvement of the skin condition after using skin care products and beauty, a quantitative evaluation method for skin surface state and texture is presented, which is convenient, fast and non-destructive. Human skin images were collected by image sensors. Firstly, the median filter of the 3 × 3 window is used and then the location of the hairy pixels on the skin is accurately detected according to the gray mean value and color information. The bilinear interpolation is used to modify the gray value of the hairy pixels in order to eliminate the negative effect of noise and tiny hairs on the texture. After the above pretreatment, the gray level co-occurrence matrix (GLCM) is calculated. On the basis of this, the four characteristic parameters, including the second moment, contrast, entropy and correlation, and their mean value are calculated at 45 ° intervals. The quantitative evaluation model of skin texture based on GLCM is established, which can calculate the comprehensive parameters of skin condition. Experiments show that using this method evaluates the skin condition, both based on biochemical indicators of skin evaluation methods in line, but also fully consistent with the human visual experience. This method overcomes the shortcomings of the biochemical evaluation method of skin damage and long waiting time, also the subjectivity and fuzziness of the visual evaluation, which achieves the non-destructive, rapid and quantitative evaluation of skin condition. It can be used for health assessment or classification of the skin condition, also can quantitatively evaluate the subtle improvement of skin condition after using skin care products or stage beauty.
Hypomagnesemia predicts postoperative biochemical hypocalcemia after thyroidectomy.
Luo, Han; Yang, Hongliu; Zhao, Wanjun; Wei, Tao; Su, Anping; Wang, Bin; Zhu, Jingqiang
2017-05-25
To investigate the role of magnesium in biochemical and symptomatic hypocalcemia, a retrospective study was conducted. Less-than-total thyroidectomy patients were excluded from the final analysis. Identified the risk factors of biochemical and symptomatic hypocalcemia, and investigated the correlation by logistic regression and correlation test respectively. A total of 304 patients were included in the final analysis. General incidence of hypomagnesemia was 23.36%. Logistic regression showed that gender (female) (OR = 2.238, p = 0.015) and postoperative hypomagnesemia (OR = 2.010, p = 0.017) were independent risk factors for biochemical hypocalcemia. Both Pearson and partial correlation tests indicated there was indeed significant relation between calcium and magnesium. However, relative decreasing of iPTH (>70%) (6.691, p < 0.001) and hypocalcemia (2.222, p = 0.046) were identified as risk factors of symptomatic hypocalcemia. The difference remained significant even in normoparathyroidism patients. Postoperative hypomagnesemia was independent risk factor of biochemical hypocalcemia. Relative decline of iPTH was predominating in predicting symptomatic hypocalcemia.
Isolation of Extracellular Vesicles: General Methodologies and Latest Trends
Konoshenko, Maria Yu.; Laktionov, Pavel P.
2018-01-01
Background Extracellular vesicles (EVs) play an essential role in the communication between cells and transport of diagnostically significant molecules. A wide diversity of approaches utilizing different biochemical properties of EVs and a lack of accepted protocols make data interpretation very challenging. Scope of Review This review consolidates the data on the classical and state-of-the-art methods for isolation of EVs, including exosomes, highlighting the advantages and disadvantages of each method. Various characteristics of individual methods, including isolation efficiency, EV yield, properties of isolated EVs, and labor consumption are compared. Major Conclusions A mixed population of vesicles is obtained in most studies of EVs for all used isolation methods. The properties of an analyzed sample should be taken into account when planning an experiment aimed at studying and using these vesicles. The problem of adequate EVs isolation methods still remains; it might not be possible to develop a universal EV isolation method but the available protocols can be used towards solving particular types of problems. General Significance With the wide use of EVs for diagnosis and therapy of various diseases the evaluation of existing methods for EV isolation is one of the key problems in modern biology and medicine. PMID:29662902
Premuzic, Eugene T.; Lin, Mow S.
1999-01-12
A process for biochemical conversion of heavy crude oils is provided. The process includes contacting heavy crude oils with adapted biocatalysts. The resulting upgraded oil shows, a relative increase in saturated hydrocarbons, emulsions and oxygenates and a decrease in compounds containing in organic sulfur, organic nitrogen and trace metals. Adapted microorganisms which have been modified under challenged growth processes are also disclosed.
Premuzic, E.T.; Lin, M.S.
1999-01-12
A process for biochemical conversion of heavy crude oils is provided. The process includes contacting heavy crude oils with adapted biocatalysts. The resulting upgraded oil shows, a relative increase in saturated hydrocarbons, emulsions and oxygenates and a decrease in compounds containing organic sulfur, organic nitrogen and trace metals. Adapted microorganisms which have been modified under challenged growth processes are also disclosed. 121 figs.
Verma, Priyanka; Kumar, Manoj; Mishra, Girish; Sahoo, Dinabandhu
2017-02-01
In the present study bio prospecting of thirty seaweeds from Indian coasts was analyzed for their biochemical components including pigments, fatty acid and ash content. Multivariate analysis of biochemical components and fatty acids was done using Principal Component Analysis (PCA) and Agglomerative hierarchical clustering (AHC) to manifest chemotaxonomic relationship among various seaweeds. The overall analysis suggests that these seaweeds have multi-functional properties and can be utilized as promising bioresource for proteins, lipids, pigments and carbohydrates for the food/feed and biofuel industry. Copyright © 2016. Published by Elsevier Ltd.
Osipiuk, Jerzy; Mulligan, Rory; Bargassa, Monireh; Hamilton, John E; Cunningham, Mark A; Joachimiak, Andrzej
2012-06-01
The crystal structure of SO1698 protein from Shewanella oneidensis was determined by a SAD method and refined to 1.57 Å. The structure is a β sandwich that unexpectedly consists of two polypeptides; the N-terminal fragment includes residues 1-116, and the C-terminal one includes residues 117-125. Electron density also displayed the Lys-98 side chain covalently linked to Asp-116. The putative active site residues involved in self-cleavage were identified; point mutants were produced and characterized structurally and in a biochemical assay. Numerical simulations utilizing molecular dynamics and hybrid quantum/classical calculations suggest a mechanism involving activation of a water molecule coordinated by a catalytic aspartic acid.
Know-how and know-why in biochemical engineering.
von Stockar, U; Valentinotti, S; Marison, I; Cannizzaro, C; Herwig, C
2003-08-01
This contribution analyzes the position of biochemical engineering in general and bioprocess engineering particularly in the force fields between fundamental science and applications, and between academia and industry. By using culture technology as an example, it can be shown that bioprocess engineering has moved slowly but steadily from an empirical art concerned with mainly know-how to a science elucidating the know-why of culture behavior. Highly powerful monitoring tools enable biochemical engineers to understand and explain quantitatively the activity of cellular culture on a metabolic basis. Among these monitoring tools are not just semi-online analyses of culture broth by HPLC, GC and FIA, but, increasingly, also noninvasive methods such as midrange IR, Raman and capacitance spectroscopy, as well as online calorimetry. The detailed and quantitative insight into the metabolome and the fluxome that bioprocess engineers are establishing offers an unprecedented opportunity for building bridges between molecular biology and engineering biosciences. Thus, one of the major tasks of biochemical engineering sciences is not developing new know-how for industrial applications, but elucidating the know-why in biochemical engineering by conducting research on the underlying scientific fundamentals.
Development of class model based on blood biochemical parameters as a diagnostic tool of PSE meat.
Qu, Daofeng; Zhou, Xu; Yang, Feng; Tian, Shiyi; Zhang, Xiaojun; Ma, Lin; Han, Jianzhong
2017-06-01
A fast, sensitive and effective method based on the blood biochemical parameters for the detection of PSE meat was developed in this study. A total of 200 pigs were slaughtered in the same slaughterhouse. Meat quality was evaluated by measuring pH, electrical conductivity and color at 45min, 2h and 24h after slaughtering in M. longissimus thoracis et lumborum (LD). Blood biochemical parameters were determined in blood samples collected during carcass bleeding. Principal component analysis (PCA) biplot showed that high levels of exsanguination Creatine Kinase, Lactate Dehydrogenase, Aspertate aminotransferase, blood glucose and lactate were associated with the PSE meat, and the five biochemical parameters were found to be good indicators of PSE meat Discriminant function analysis (DFA) was able to clearly identify PSE meat using the five biochemical parameters as input data, and the class model is an effective diagnostic tool in pigs which can be used to detect the PSE meat and reduce economic loss for the company. Copyright © 2017 Elsevier Ltd. All rights reserved.
An Inductive Logic Programming Approach to Validate Hexose Binding Biochemical Knowledge.
Nassif, Houssam; Al-Ali, Hassan; Khuri, Sawsan; Keirouz, Walid; Page, David
2010-01-01
Hexoses are simple sugars that play a key role in many cellular pathways, and in the regulation of development and disease mechanisms. Current protein-sugar computational models are based, at least partially, on prior biochemical findings and knowledge. They incorporate different parts of these findings in predictive black-box models. We investigate the empirical support for biochemical findings by comparing Inductive Logic Programming (ILP) induced rules to actual biochemical results. We mine the Protein Data Bank for a representative data set of hexose binding sites, non-hexose binding sites and surface grooves. We build an ILP model of hexose-binding sites and evaluate our results against several baseline machine learning classifiers. Our method achieves an accuracy similar to that of other black-box classifiers while providing insight into the discriminating process. In addition, it confirms wet-lab findings and reveals a previously unreported Trp-Glu amino acids dependency.
Nuclear microscopy of sperm cell elemental structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bench, G.S.; Balhorn, R.; Friz, A.M.
1994-09-28
Theories suggest there is a link between protamine concentrations in individual sperm and male fertility. Previously, biochemical analyses have used pooled samples containing millions of sperm to determine protamine concentrations. These methods have not been able to determine what percentage of morphologically normal sperm are biochemically defective and potentially infertile. Nuclear microscopy has been utilized to measure elemental profiles at the single sperm level. By measuring the amount of phosphorus and sulfur, the total DNA and protamine content in individual sperm from fertile bull and mouse semen have been determined. These values agree with results obtained from other biochemical analyses.more » Nuclear microscopy shows promise for measuring elemental profiles in the chromatin of individual sperm. The technique may be able to resolve theories regarding the importance of protamines to male fertility and identify biochemical defects responsible for certain types of male infertility.« less
NASA Astrophysics Data System (ADS)
Zhang, Ji; Li, Bing; Wang, Qi; Li, Chengzhi; Zhang, Yinming; Lin, Hancheng; Wang, Zhenyuan
2017-02-01
Postmortem interval (PMI) determination is one of the most challenging tasks in forensic medicine due to a lack of accurate and reliable methods. It is especially difficult for late PMI determination. Although many attempts with various types of body fluids based on chemical methods have been made to solve this problem, few investigations are focused on blood samples. In this study, we employed an attenuated total reflection (ATR)-Fourier transform infrared (FTIR) technique coupled with principle component analysis (PCA) to monitor biochemical changes in rabbit plasma with increasing PMI. Partial least square (PLS) model was used based on the spectral data for PMI prediction in an independent sample set. Our results revealed that postmortem chemical changes in compositions of the plasma were time-dependent, and various components including proteins, lipids and nucleic acids contributed to the discrimination of the samples at different time points. A satisfactory prediction within 48 h postmortem was performed by the combined PLS model with a good fitting between actual and predicted PMI of 0.984 and with an error of ± 1.92 h. In consideration of the simplicity and portability of ATR-FTIR, our preliminary study provides an experimental and theoretical basis for application of this technique in forensic practice.
Brachytherapy of prostate cancer after colectomy for colorectal cancer: pilot experience.
Koutrouvelis, Panos G; Theodorescu, Dan; Katz, Stuart; Lailas, Niko; Hendricks, Fred
2005-01-01
We present a method of brachytherapy for prostate cancer using a 3-dimensional stereotactic system and computerized tomography guidance in patients without a rectum due to previous treatment for colorectal cancer. From June 1994 to November 2003 a cohort of 800 patients were treated with brachytherapy for prostate cancer. Four patients had previously been treated for colorectal cancer with 4,500 cGy external beam radiation therapy, abdominoperineal resection and chemotherapy, while 1 underwent abdominoperineal resection alone for ulcerative colitis. Because of previous radiation therapy, these patients were not candidates for salvage external beam radiation therapy or radical prostatectomy and they had no rectum for transrectal ultrasound guided transperineal brachytherapy or cryotherapy. A previously described, 3-dimensional stereotactic system was used for brachytherapy in these patients. The prescribed radiation dose was 120 to 144 Gy with iodine seeds in rapid strand format. Patient followup included clinical examination and serum prostate specific antigen measurement. Average followup was 18.6 months. Four patients had excellent biochemical control, while 1 had biochemical failure. Patients did not experience any gastrointestinal morbidity. One patient had a stricture of the distal ureter, requiring a stent. Three-dimensional computerized tomography guided brachytherapy for prostate cancer in patients with a history of colorectal cancer who have no rectum is a feasible method of treatment.
Biochemical response and the effects of bariatric surgeries on type 2 diabetes
NASA Astrophysics Data System (ADS)
Allen, Roland; Hughes, Tyler; Lerd Ng, Jia; Ortiz, Roberto; Abou Ghantous, Michel; Bouhali, Othmane; Arredouani, Abdelilah
2013-03-01
A general method is introduced for calculating the biochemical response to pharmaceuticals, surgeries, or other medical interventions. This method is then applied in a simple model of the response to Roux-en-Y gastric bypass (RYGB) surgery in obese diabetic patients. We specifically address the amazing fact that glycemia correction is usually achieved immediately after RYGB surgery, long before there is any appreciable weight loss. Many studies indicate that this result is not due merely to caloric restriction, and it is usually attributed to an increase in glucagon-like peptide 1 (GLP-1) levels observed after the surgery. However, our model indicates that this mechanism alone is not sufficient to explain either the largest declines in glucose levels or the measured declines in the homeostatic model assessment insulin resistance (HOMA-IR). The most robust additional mechanism would be production of a factor which opens an insulin-independent pathway for glucose transport into cells, perhaps related to the well-established insulin-independent pathway associated with exercise. Potential candidates include bradykinin, a 9 amino acid peptide. If such a substance were found to exist, it would offer hope for medications which mimic the immediate beneficial effect of RYGB surgery. Supported by Qatar Biomedical Research Institute and Science Program at Texas A&M University at Qatar
Alcohols as alkylating agents in heteroarene C-H functionalization
NASA Astrophysics Data System (ADS)
Jin, Jian; MacMillan, David W. C.
2015-09-01
Redox processes and radical intermediates are found in many biochemical processes, including deoxyribonucleotide synthesis and oxidative DNA damage. One of the core principles underlying DNA biosynthesis is the radical-mediated elimination of H2O to deoxygenate ribonucleotides, an example of `spin-centre shift', during which an alcohol C-O bond is cleaved, resulting in a carbon-centred radical intermediate. Although spin-centre shift is a well-understood biochemical process, it is underused by the synthetic organic chemistry community. We wondered whether it would be possible to take advantage of this naturally occurring process to accomplish mild, non-traditional alkylation reactions using alcohols as radical precursors. Because conventional radical-based alkylation methods require the use of stoichiometric oxidants, increased temperatures or peroxides, a mild protocol using simple and abundant alkylating agents would have considerable use in the synthesis of diversely functionalized pharmacophores. Here we describe the development of a dual catalytic alkylation of heteroarenes, using alcohols as mild alkylating reagents. This method represents the first, to our knowledge, broadly applicable use of unactivated alcohols as latent alkylating reagents, achieved via the successful merger of photoredox and hydrogen atom transfer catalysis. The value of this multi-catalytic protocol has been demonstrated through the late-stage functionalization of the medicinal agents, fasudil and milrinone.
Alcohols as alkylating agents in heteroarene C-H functionalization.
Jin, Jian; MacMillan, David W C
2015-09-03
Redox processes and radical intermediates are found in many biochemical processes, including deoxyribonucleotide synthesis and oxidative DNA damage. One of the core principles underlying DNA biosynthesis is the radical-mediated elimination of H2O to deoxygenate ribonucleotides, an example of 'spin-centre shift', during which an alcohol C-O bond is cleaved, resulting in a carbon-centred radical intermediate. Although spin-centre shift is a well-understood biochemical process, it is underused by the synthetic organic chemistry community. We wondered whether it would be possible to take advantage of this naturally occurring process to accomplish mild, non-traditional alkylation reactions using alcohols as radical precursors. Because conventional radical-based alkylation methods require the use of stoichiometric oxidants, increased temperatures or peroxides, a mild protocol using simple and abundant alkylating agents would have considerable use in the synthesis of diversely functionalized pharmacophores. Here we describe the development of a dual catalytic alkylation of heteroarenes, using alcohols as mild alkylating reagents. This method represents the first, to our knowledge, broadly applicable use of unactivated alcohols as latent alkylating reagents, achieved via the successful merger of photoredox and hydrogen atom transfer catalysis. The value of this multi-catalytic protocol has been demonstrated through the late-stage functionalization of the medicinal agents, fasudil and milrinone.
Tan, Nelly; Shen, Luyao; Khoshnoodi, Pooria; Alcalá, Héctor E; Yu, Weixia; Hsu, William; Reiter, Robert E; Lu, David Y; Raman, Steven S
2018-05-01
We sought to identify the clinical and magnetic resonance imaging variables predictive of biochemical recurrence after robotic assisted radical prostatectomy in patients who underwent multiparametric 3 Tesla prostate magnetic resonance imaging. We performed an institutional review board approved, HIPAA (Health Insurance Portability and Accountability Act) compliant, single arm observational study of 3 Tesla multiparametric magnetic resonance imaging prior to robotic assisted radical prostatectomy from December 2009 to March 2016. Clinical, magnetic resonance imaging and pathological information, and clinical outcomes were compiled. Biochemical recurrence was defined as prostate specific antigen 0.2 ng/cc or greater. Univariate and multivariate regression analysis was performed. Biochemical recurrence had developed in 62 of the 255 men (24.3%) included in the study at a median followup of 23.5 months. Compared to the subcohort without biochemical recurrence the subcohort with biochemical recurrence had a greater proportion of patients with a high grade biopsy Gleason score, higher preoperative prostate specific antigen (7.4 vs 5.6 ng/ml), intermediate and high D'Amico classifications, larger tumor volume on magnetic resonance imaging (0.66 vs 0.30 ml), higher PI-RADS® (Prostate Imaging-Reporting and Data System) version 2 category lesions, a greater proportion of intermediate and high grade radical prostatectomy Gleason score lesions, higher pathological T3 stage (all p <0.01) and a higher positive surgical margin rate (19.3% vs 7.8%, p = 0.016). On multivariable analysis only tumor volume on magnetic resonance imaging (adjusted OR 1.57, p = 0.016), pathological T stage (adjusted OR 2.26, p = 0.02), positive surgical margin (adjusted OR 5.0, p = 0.004) and radical prostatectomy Gleason score (adjusted OR 2.29, p = 0.004) predicted biochemical recurrence. In this cohort tumor volume on magnetic resonance imaging and pathological variables, including Gleason score, staging and positive surgical margins, significantly predicted biochemical recurrence. This suggests an important new imaging biomarker. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Keenan, Alexandra B; Jenkins, Sherry L; Jagodnik, Kathleen M; Koplev, Simon; He, Edward; Torre, Denis; Wang, Zichen; Dohlman, Anders B; Silverstein, Moshe C; Lachmann, Alexander; Kuleshov, Maxim V; Ma'ayan, Avi; Stathias, Vasileios; Terryn, Raymond; Cooper, Daniel; Forlin, Michele; Koleti, Amar; Vidovic, Dusica; Chung, Caty; Schürer, Stephan C; Vasiliauskas, Jouzas; Pilarczyk, Marcin; Shamsaei, Behrouz; Fazel, Mehdi; Ren, Yan; Niu, Wen; Clark, Nicholas A; White, Shana; Mahi, Naim; Zhang, Lixia; Kouril, Michal; Reichard, John F; Sivaganesan, Siva; Medvedovic, Mario; Meller, Jaroslaw; Koch, Rick J; Birtwistle, Marc R; Iyengar, Ravi; Sobie, Eric A; Azeloglu, Evren U; Kaye, Julia; Osterloh, Jeannette; Haston, Kelly; Kalra, Jaslin; Finkbiener, Steve; Li, Jonathan; Milani, Pamela; Adam, Miriam; Escalante-Chong, Renan; Sachs, Karen; Lenail, Alex; Ramamoorthy, Divya; Fraenkel, Ernest; Daigle, Gavin; Hussain, Uzma; Coye, Alyssa; Rothstein, Jeffrey; Sareen, Dhruv; Ornelas, Loren; Banuelos, Maria; Mandefro, Berhan; Ho, Ritchie; Svendsen, Clive N; Lim, Ryan G; Stocksdale, Jennifer; Casale, Malcolm S; Thompson, Terri G; Wu, Jie; Thompson, Leslie M; Dardov, Victoria; Venkatraman, Vidya; Matlock, Andrea; Van Eyk, Jennifer E; Jaffe, Jacob D; Papanastasiou, Malvina; Subramanian, Aravind; Golub, Todd R; Erickson, Sean D; Fallahi-Sichani, Mohammad; Hafner, Marc; Gray, Nathanael S; Lin, Jia-Ren; Mills, Caitlin E; Muhlich, Jeremy L; Niepel, Mario; Shamu, Caroline E; Williams, Elizabeth H; Wrobel, David; Sorger, Peter K; Heiser, Laura M; Gray, Joe W; Korkola, James E; Mills, Gordon B; LaBarge, Mark; Feiler, Heidi S; Dane, Mark A; Bucher, Elmar; Nederlof, Michel; Sudar, Damir; Gross, Sean; Kilburn, David F; Smith, Rebecca; Devlin, Kaylyn; Margolis, Ron; Derr, Leslie; Lee, Albert; Pillai, Ajay
2018-01-24
The Library of Integrated Network-Based Cellular Signatures (LINCS) is an NIH Common Fund program that catalogs how human cells globally respond to chemical, genetic, and disease perturbations. Resources generated by LINCS include experimental and computational methods, visualization tools, molecular and imaging data, and signatures. By assembling an integrated picture of the range of responses of human cells exposed to many perturbations, the LINCS program aims to better understand human disease and to advance the development of new therapies. Perturbations under study include drugs, genetic perturbations, tissue micro-environments, antibodies, and disease-causing mutations. Responses to perturbations are measured by transcript profiling, mass spectrometry, cell imaging, and biochemical methods, among other assays. The LINCS program focuses on cellular physiology shared among tissues and cell types relevant to an array of diseases, including cancer, heart disease, and neurodegenerative disorders. This Perspective describes LINCS technologies, datasets, tools, and approaches to data accessibility and reusability. Copyright © 2017 Elsevier Inc. All rights reserved.
Ge, Hao; Qian, Hong
2011-01-01
A theory for an non-equilibrium phase transition in a driven biochemical network is presented. The theory is based on the chemical master equation (CME) formulation of mesoscopic biochemical reactions and the mathematical method of large deviations. The large deviations theory provides an analytical tool connecting the macroscopic multi-stability of an open chemical system with the multi-scale dynamics of its mesoscopic counterpart. It shows a corresponding non-equilibrium phase transition among multiple stochastic attractors. As an example, in the canonical phosphorylation–dephosphorylation system with feedback that exhibits bistability, we show that the non-equilibrium steady-state (NESS) phase transition has all the characteristics of classic equilibrium phase transition: Maxwell construction, a discontinuous first-derivative of the ‘free energy function’, Lee–Yang's zero for a generating function and a critical point that matches the cusp in nonlinear bifurcation theory. To the biochemical system, the mathematical analysis suggests three distinct timescales and needed levels of description. They are (i) molecular signalling, (ii) biochemical network nonlinear dynamics, and (iii) cellular evolution. For finite mesoscopic systems such as a cell, motions associated with (i) and (iii) are stochastic while that with (ii) is deterministic. Both (ii) and (iii) are emergent properties of a dynamic biochemical network. PMID:20466813
Jorge, E M; Silva, C J O; Ritter, R A; Monteiro, M V B; Albuquerque, N I; Kahwage, P R; Monteiro, F O B; Costa, C T C; Rahal, S C; Silva Filho, E
2015-11-25
Complete blood counts and blood biochemical analyses are laboratory tests that allow the monitoring of physiological condition, nutrition, and health in free-living or captive wild animals. When interpreting these tests, it is essential to compare the results with reference ranges that are suitable for the species. Few studies have been conducted on the hematological and biochemical characteristics of Tayassu tajacu, particularly for animals raised in the Amazon biome. The objectives of this study were to evaluate the influence of age and gender on the hematological and biochemical profiles of captive T. tajacu, and to establish reference intervals for these parameters. Complete blood counts and biochemical analyses were performed using manual methods and semi-automatic equipment, respectively. There were significant differences in relation to age in hematocrit and hemoglobin levels, and mean cell volumes, in captive T. tajacu. No basophils were observed, and the neutrophil:lymphocyte ratio was less than 1. Levels of total protein, urea, phosphorus, and alkaline phosphatase were significantly affected by age (P < 0.05). Gender did not affect any of the results. The hematological and biochemical parameters for this species were determined, and may be used as reference ranges for captive T. tajacu.
Zakharova, Irina B; Lopasteyskaya, Yana A; Toporkov, Andrey V; Viktorov, Dmitry V
2018-01-01
Background: Burkholderia pseudomallei is a Gram-negative saprophytic soil bacterium that causes melioidosis, a potentially fatal disease endemic in wet tropical areas. The currently available biochemical identification systems can misidentify some strains of B. pseudomallei. The aim of the present study was to identify the biochemical features of B. pseudomallei, which can affect its correct identification by Vitek 2 system. Materials and Methods: The biochemical patterns of 40 B. pseudomallei strains were obtained using Vitek 2 GN cards. The average contribution of biochemical tests in overall dissimilarities between correctly and incorrectly identified strains was assessed using nonmetric multidimensional scaling. Results: It was found (R statistic of 0.836, P = 0.001) that a combination of negative N-acetyl galactosaminidase, β-N-acetyl glucosaminidase, phosphatase, and positive D-cellobiase (dCEL), tyrosine arylamidase (TyrA), and L-proline arylamidase (ProA) tests leads to low discrimination of B. pseudomallei, whereas a set of positive dCEL and negative N-acetyl galactosaminidase, TyrA, and ProA determines the wrong identification of B. pseudomallei as Burkholderia cepacia complex. Conclusion: The further expansion of the Vitek 2 identification keys is needed for correct identification of atypical or regionally distributed biochemical profiles of B. pseudomallei. PMID:29563716
NASA Astrophysics Data System (ADS)
Akbari, Mohsen; Torki, Mehran
2014-08-01
A study was conducted using 240 female day-old broiler chicks to evaluate the effects of dietary chromium picolinate (CrPic), peppermint essential oil (P.mint), or their combination on growth performance and blood biochemical parameters of female broiler chicks raised under heat stress conditions (HS, 23.9 to 38 °C cycling). Average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were obtained from 1 to 42 days of age. Furthermore, at the end of the experiment (day 42), birds were bled to determine some blood biochemical parameters and weighed for final body weight (BW). ADFI, ADG, and BW were not influenced significantly by dietary CrPic and P.mint ( P > 0.05). A significant interaction between dietary CrPic and P.mint on FCR ( P = 0.012) was detected. FCR significantly decreased in chicks fed the diet including both CrPic and P.mint compared with the CrPic group. Significant interaction between dietary P.mint and CrPic on serum concentrations of triglycerides, glucose, and albumin were observed ( P < 0.05), but the other measured blood biochemical parameters were not statistically affected by dietary treatments ( P > 0.05). The serum concentrations of glucose, triglycerides were decreased ( P < 0.05) in broilers fed the diet including both CrPic and P.mint. Plasma chromium (Cr) content increased significantly ( P < 0.05) in birds fed the CrPic-included diet compared with the control group ( P < 0.05). From the results of the present experiment it can be concluded that dietary supplementation with combined P.mint and CrPic could have beneficial effects on some blood biochemical parameters of female chicks reared under heat stress conditions.
Akbari, Mohsen; Torki, Mehran
2014-08-01
A study was conducted using 240 female day-old broiler chicks to evaluate the effects of dietary chromium picolinate (CrPic), peppermint essential oil (P.mint), or their combination on growth performance and blood biochemical parameters of female broiler chicks raised under heat stress conditions (HS, 23.9 to 38 °C cycling). Average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were obtained from 1 to 42 days of age. Furthermore, at the end of the experiment (day 42), birds were bled to determine some blood biochemical parameters and weighed for final body weight (BW). ADFI, ADG, and BW were not influenced significantly by dietary CrPic and P.mint (P>0.05). A significant interaction between dietary CrPic and P.mint on FCR (P=0.012) was detected. FCR significantly decreased in chicks fed the diet including both CrPic and P.mint compared with the CrPic group. Significant interaction between dietary P.mint and CrPic on serum concentrations of triglycerides, glucose, and albumin were observed (P<0.05), but the other measured blood biochemical parameters were not statistically affected by dietary treatments (P>0.05). The serum concentrations of glucose, triglycerides were decreased (P<0.05) in broilers fed the diet including both CrPic and P.mint. Plasma chromium (Cr) content increased significantly (P<0.05) in birds fed the CrPic-included diet compared with the control group (P<0.05). From the results of the present experiment it can be concluded that dietary supplementation with combined P.mint and CrPic could have beneficial effects on some blood biochemical parameters of female chicks reared under heat stress conditions.
Mullins, Fiona; O'Shea, Paula; FitzGerald, Roland; Tormey, William
2011-10-08
The aim of the study was to define the analytical and diagnostic performance of the Labor Diagnostica Nord (LDN) 2-Met plasma ELISA assay for fractionated plasma metanephrines in the biochemical diagnosis of phaeochromocytoma. The stated manufacturer's performance characteristics were assessed. Clinical utility was evaluated against liquid chromatography tandem mass spectrometry (LC-MS/MS) using bias, sensitivity and specificity outcomes. Samples (n=73) were collected from patients in whom phaeochromocytoma had been excluded (n=60) based on low probability of disease, repeat negative testing for urinary fractionated catecholamines and metanephrines, lack of radiological and histological evidence of a tumour and from a group (n=13) in whom the tumour had been histologically confirmed. Blood collected into k(2)EDTA tubes was processed within 30 min. Separated plasma was aliquoted (×2) and frozen at -40°C prior to analyses. One aliquot was analysed for plasma metanephrines using the LDN 2-Met ELISA and the other by LC-MS/MS. The mean bias of -32% for normetanephrine (ELISA) when compared to the reference method (LC-MS/MS) makes under-diagnosis of phaeochromocytoma likely. The sensitivity of the assay (100%) was equal to the reference method, but specificity (88.3%) lower than the reference method (95%), making it less than optimum for the biochemical diagnosis of phaeochromocytoma. Plasma-free metanephrines as measured by Labor Diagnostica Nord (LDN) 2-Met ELISA do not display test characteristics that would support their introduction or continuation as part of a screening protocol for the biochemical detection of phaeochromocytoma unless the calibration problem identified is corrected and other more accurate and analytically specific methods remain unavailable.
Clavibacter michiganensis subsp. phaseoli subsp. nov., pathogenic in bean.
González, Ana J; Trapiello, Estefanía
2014-05-01
A yellow Gram-reaction-positive bacterium isolated from bean seeds (Phaseolus vulgaris L.) was identified as Clavibacter michiganensis by 16S rRNA gene sequencing. Molecular methods were employed in order to identify the subspecies. Such methods included the amplification of specific sequences by PCR, 16S amplified rDNA restriction analysis (ARDRA), RFLP and multilocus sequence analysis as well as the analysis of biochemical and phenotypic traits including API 50CH and API ZYM results. The results showed that strain LPPA 982T did not represent any known subspecies of C. michiganensis. Pathogenicity tests revealed that the strain is a bean pathogen causing a newly identified bacterial disease that we name bacterial bean leaf yellowing. On the basis of these results, strain LPPA 982T is regarded as representing a novel subspecies for which the name Clavibacter michiganensis subsp. phaseoli subsp. nov. is proposed. The type strain is LPPA 982T (=CECT 8144T=LMG 27667T).
In-situ investigation of protein and DNA structure using UVRRS
NASA Astrophysics Data System (ADS)
Greek, L. Shane; Schulze, H. Georg; Blades, Michael W.; Haynes, Charles A.; Turner, Robin F. B.
1997-05-01
Ultraviolet resonance Raman spectroscopy (UVRRS) has the potential to become a sensitive, specific, versatile bioanalytical and biophysical technique for routine investigations of proteins, DNA, and their monomeric components, as well as a variety smaller, physiologically important aromatic molecules. The transition of UVRRS from a complex, specialized spectroscopic method to a common laboratory assay depends upon several developments, including a robust sample introduction method permitting routine, in situ analysis in standard laboratory environments. To this end, we recently reported the first fiber-optic probes suitable for deep-UV pulsed laser UVRRS. In this paper, we extend this work by demonstrating the applicability of such probes to studies of biochemical relevance, including investigations of the resonance enhancement of phosphotyrosine, thermal denaturation of RNase T1, and specific and non-specific protein binding. The advantages and disadvantages of the probes are discussed with reference to sample conditions and probe design considerations.
Gnaiger, E; Bitterlich, G
1984-06-01
Carbohydrate, lipid, and protein compositions are stoichiometrically related to organic CHN (carbon, hydrogen, nitrogen) contents. Elemental CHN analyses of total biomass and ash, therefore, provide a basis for the calculation of proximate biochemical composition and bomb caloric value. The classical nitrogen to protein conversion factor (6.25) should be replaced by 5.8±0.13. A linear relation exists between the mass fraction of non-protein carbon and the carbohydrate and lipid content. Residual water in dry organic matter can be estimated with the additional information derived from hydrogen measurements.The stoichiometric CHN method and direct biochemical analysis agreed within 10% of ash-free dry biomass (for muscle, liver and fat tissue of silver carp; gut contents composed of detritus and algae; commercial fish food). The detrital material, however, had to be corrected for non-protein nitrogen.A linear relationship between bomb caloric value and organic carbon fractions was derived on the basis of thermodynamic and stoichiometric principles, in agreement with experimental data published for bacteria, algae, protozoa and invertebrates. The highly automatic stoichiometric CHN method for the separation of nutrient contents in biomass extends existing ecophysiological concepts for the construction of balanced carbon and nitrogen, as well as biochemical and energy budgets.
Improved prediction of biochemical recurrence after radical prostatectomy by genetic polymorphisms.
Morote, Juan; Del Amo, Jokin; Borque, Angel; Ars, Elisabet; Hernández, Carlos; Herranz, Felipe; Arruza, Antonio; Llarena, Roberto; Planas, Jacques; Viso, María J; Palou, Joan; Raventós, Carles X; Tejedor, Diego; Artieda, Marta; Simón, Laureano; Martínez, Antonio; Rioja, Luis A
2010-08-01
Single nucleotide polymorphisms are inherited genetic variations that can predispose or protect individuals against clinical events. We hypothesized that single nucleotide polymorphism profiling may improve the prediction of biochemical recurrence after radical prostatectomy. We performed a retrospective, multi-institutional study of 703 patients treated with radical prostatectomy for clinically localized prostate cancer who had at least 5 years of followup after surgery. All patients were genotyped for 83 prostate cancer related single nucleotide polymorphisms using a low density oligonucleotide microarray. Baseline clinicopathological variables and single nucleotide polymorphisms were analyzed to predict biochemical recurrence within 5 years using stepwise logistic regression. Discrimination was measured by ROC curve AUC, specificity, sensitivity, predictive values, net reclassification improvement and integrated discrimination index. The overall biochemical recurrence rate was 35%. The model with the best fit combined 8 covariates, including the 5 clinicopathological variables prostate specific antigen, Gleason score, pathological stage, lymph node involvement and margin status, and 3 single nucleotide polymorphisms at the KLK2, SULT1A1 and TLR4 genes. Model predictive power was defined by 80% positive predictive value, 74% negative predictive value and an AUC of 0.78. The model based on clinicopathological variables plus single nucleotide polymorphisms showed significant improvement over the model without single nucleotide polymorphisms, as indicated by 23.3% net reclassification improvement (p = 0.003), integrated discrimination index (p <0.001) and likelihood ratio test (p <0.001). Internal validation proved model robustness (bootstrap corrected AUC 0.78, range 0.74 to 0.82). The calibration plot showed close agreement between biochemical recurrence observed and predicted probabilities. Predicting biochemical recurrence after radical prostatectomy based on clinicopathological data can be significantly improved by including patient genetic information. Copyright (c) 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Chen, Connie H; Harris, Mary Beth; Partipilo, M Luisa; Welch, Kathleen B; Teitelbaum, Daniel H; Blackmer, Allison B
2016-08-01
For patients dependent on parenteral nutrition (PN), selenium must be supplemented intravenously. A nationwide intravenous selenium shortage began in April 2011. The impact of this shortage on PN-dependent infants was evaluated by examining the provision of selenium, development of biochemical deficiency, and costs associated with the shortage. This single-center, retrospective study included PN-dependent infants aged ≤1 year who weighed ≤30 kg, received PN for ≥1 month, and had ≥1 serum selenium measurement. The primary outcome was the incidence of biochemical selenium deficiency. Secondary outcomes included severity of biochemical deficiency, clinical manifestations, costs, and relationship between serum selenium levels and selenium dose. The average selenium dose decreased 2-fold during the shortage (2.1 ± 1.2 µg/kg/d; range, 0.2-4.6 µg/kg/d) versus the nonshortage period (3.8 ± 1 µg/kg/d; range, 2.4-6 µg/kg/d; P < .001). A linear relationship between serum selenium concentration and selenium dose was observed (r(2) = 0.42), with a dose of 6 µg/kg/d expected to result in normal serum levels in most cases. Similar proportions of patients developed biochemical deficiency in both groups: shortage period, 59.1%; nonshortage, 66.7%; P = .13. The severity of biochemical deficiency was similar between groups. A significant increase in incremental cost during the shortage was observed. This is the first study examining the impact of the intravenous selenium shortage on PN-dependent infants. Both groups exhibited similarly high incidences of biochemical selenium deficiency, suggesting higher empiric doses may benefit this population. However, ongoing shortages limit the ability to provide supplementation. © 2015 American Society for Parenteral and Enteral Nutrition.
Heuett, William J; Beard, Daniel A; Qian, Hong
2008-01-01
Background Several approaches, including metabolic control analysis (MCA), flux balance analysis (FBA), correlation metric construction (CMC), and biochemical circuit theory (BCT), have been developed for the quantitative analysis of complex biochemical networks. Here, we present a comprehensive theory of linear analysis for nonequilibrium steady-state (NESS) biochemical reaction networks that unites these disparate approaches in a common mathematical framework and thermodynamic basis. Results In this theory a number of relationships between key matrices are introduced: the matrix A obtained in the standard, linear-dynamic-stability analysis of the steady-state can be decomposed as A = SRT where R and S are directly related to the elasticity-coefficient matrix for the fluxes and chemical potentials in MCA, respectively; the control-coefficients for the fluxes and chemical potentials can be written in terms of RTBS and STBS respectively where matrix B is the inverse of A; the matrix S is precisely the stoichiometric matrix in FBA; and the matrix eAt plays a central role in CMC. Conclusion One key finding that emerges from this analysis is that the well-known summation theorems in MCA take different forms depending on whether metabolic steady-state is maintained by flux injection or concentration clamping. We demonstrate that if rate-limiting steps exist in a biochemical pathway, they are the steps with smallest biochemical conductances and largest flux control-coefficients. We hypothesize that biochemical networks for cellular signaling have a different strategy for minimizing energy waste and being efficient than do biochemical networks for biosynthesis. We also discuss the intimate relationship between MCA and biochemical systems analysis (BSA). PMID:18482450
Biochemical characteristics among Mycobacterium bovis BCG substrains.
Hayashi, Daisuke; Takii, Takemasa; Mukai, Tetsu; Makino, Masahiko; Yasuda, Emi; Horita, Yasuhiro; Yamamoto, Ryuji; Fujiwara, Akiko; Kanai, Keita; Kondo, Maki; Kawarazaki, Aya; Yano, Ikuya; Yamamoto, Saburo; Onozaki, Kikuo
2010-05-01
In order to evaluate the biochemical characteristics of 14 substrains of Mycobacterium bovis bacillus Calmette Guérin (BCG) - Russia, Moreau, Japan, Sweden, Birkhaug, Danish, Glaxo, Mexico, Tice, Connaught, Montreal, Phipps, Australia and Pasteur - we performed eight different biochemical tests, including those for nitrate reduction, catalase, niacin accumulation, urease, Tween 80 hydrolysis, pyrazinamidase, p-amino salicylate degradation and resistance to thiophene 2-carboxylic acid hydrazide. Catalase activities of the substrains were all low. Data for nitrate reduction, niacin accumulation, Tween 80 hydrolysis, susceptibility to hydrogen peroxide and nitrate, and optimal pH for growth were all variable among these substrains. These findings suggest that the heterogeneities of biochemical characteristics are relevant to the differences in resistance of BCG substrains to environmental stress. The study also contributes to the re-evaluation of BCG substrains for use as vaccines.
The Pot Calling the Kettle Black? A Comparison of Measures of Current Tobacco Use
ROSENMAN, ROBERT
2014-01-01
Researchers often use the discrepancy between self-reported and biochemically assessed active smoking status to argue that self-reported smoking status is not reliable, ignoring the limitations of biochemically assessed measures and treating it as the gold standard in their comparisons. Here, we employ econometric techniques to compare the accuracy of self-reported and biochemically assessed current tobacco use, taking into account measurement errors with both methods. Our approach allows estimating and comparing the sensitivity and specificity of each measure without directly observing true smoking status. The results, robust to several alternative specifications, suggest that there is no clear reason to think that one measure dominates the other in accuracy. PMID:25587199
Gubs'kyî, Iu I; Goriushko, G G; Belenichev, I F; Kovalenko, S I; Litvinova, N V; Marchenko, O M; Kurapova, T M; Babenko, L P; Velychko, O M
2010-01-01
Using biochemical and physicochemical methods of investigation in vivo, the effect of the substance NC-224, N-, S-chinasolone-derivative, on the lipoperoxidation activity in rat liver endoplasmatic reticulum membranes and nuclear chromatin fractions under tetrachloromethane intoxication have been studied. It was shown that NC-224 has pronounced antioxidant activity which is the biochemical basis of the substance membrane- and genome-protective effects and its ability to restore physicochemical properties of the surface and hydrophobic zones of hepatocyte membranes and structural parameter nuclear chromatin fractions in the conditions of chemical liver injury.
Dobrinja, Chiara; Silvestri, Marta; de Manzini, Nicolò
2012-01-01
Introduction. Elderly patients with primary hyperparathyroidism (pHPT) are often not referred to surgery because of their associated comorbidities that may increase surgical risk. The aim of the study was to review indications and results of minimally invasive approach parathyroidectomy in elderly patients to evaluate its impact on outcome. Materials and Methods. All patients of 70 years of age or older undergoing minimally approach parathyroidectomy at our Department from May 2005 to May 2011 were reviewed. Data collected included patients demographic information, biochemical pathology, time elapsed from pHPT diagnosis to surgical intervention, operative findings, complications, and results of postoperative biochemical studies. Results and Discussion. 37 patients were analysed. The average length of stay was 2.8 days. 11 patients were discharged within 24 hours after their operation. Morbidity included 6 transient symptomatic postoperative hypocalcemias while one patient developed a transient laryngeal nerve palsy. Time elapsed from pHPT diagnosis to first surgical visit evidences that the elderly patients were referred after their disease had progressed. Conclusions. Our data show that minimally invasive approach to parathyroid surgery seems to be safe and curative also in elderly patients with few associated risks because of combination of modern preoperative imaging, advances in surgical technique, and advances in anesthesia care. PMID:22737167
Winicur, Zev M.; Feng Zhang, Guo; Andrew Staehelin, L.
1998-01-01
To date, the lack of a method for inducing plant cells and their Golgi stacks to differentiate in a synchronous manner has made it difficult to characterize the nature and extent of Golgi retailoring in biochemical terms. Here we report that auxin deprivation can be used to induce a uniform population of suspension-cultured tobacco (Nicotiana tabacum cv BY-2) cells to differentiate synchronously during a 4-d period. Upon removal of auxin, the cells stop dividing, undergo elongation, and differentiate in a manner that mimics the formation of slime-secreting epidermal and peripheral root-cap cells. The morphological changes to the Golgi apparatus include a proportional increase in the number of trans-Golgi cisternae, a switch to larger-sized secretory vesicles that bud from the trans-Golgi cisternae, and an increase in osmium staining of the secretory products. Biochemical alterations include an increase in large, fucosylated, mucin-type glycoproteins, changes in the types of secreted arabinogalactan proteins, and an increase in the amounts and types of molecules containing the peripheral root-cap-cell-specific epitope JIM 13. Taken together, these findings support the hypothesis that auxin deprivation can be used to induce tobacco BY-2 cells to differentiate synchronously into mucilage-secreting cells. PMID:9625703
On the fate of particles liberated from hydroxyapatite coatings in vivo.
Dunne, C F; Gibbons, J; FitzPatrick, D P; Mulhall, K J; Stanton, K T
2015-03-01
Hydroxyapatite (HA) has been used as a coating for orthopaedic implants for over 30 years to help promote the fixation of orthopaedic implants into the surrounding bone. However, concerns exist about the fate of the hydroxyapatite coating and hydroxyapatite particles in vivo, especially in the wake of recent concerns about particulates from metal-on-metal bearings. Here, we assess the mechanisms of particle detachment from coated orthopaedic devices as well as the safety and performance concerns and biomedical implications arising from the liberation of the particles by review of the literature. The mechanisms that can result in the detachment of the HA coating from the implant can be mechanical or biochemical, or both. Mechanical mechanisms include implant insertion, abrasion, fatigue and micro-motion. Biochemical mechanisms that contribute to the liberation of HA particles include dissolution into extra-cellular fluid, cell-mediated processes and crystallisation of amorphous phases. The form the particles take once liberated is influenced by a number of factors such as coating method, the raw powder morphology, processing parameters, coating thickness and coating structure. This review summarises and discusses each of these factors and concludes that HA is a safe biomimetic material to use as a coating and does not cause any problems in particulate form if liberated as debris from an orthopaedic implant.
Biochemical markers in the assessment of bone disease
NASA Technical Reports Server (NTRS)
Bikle, D. D.
1997-01-01
As the mean age of our population increases, increasing attention has been paid to the diseases associated with aging, including diseases of the skeleton such as osteoporosis. Effective means of treating and possibly preventing such skeletal disorders are emerging, making their early recognition an important goal for the primary care physician. Although bone density measurements and skeletal imaging studies remain of primary diagnostic importance in this regard, a large number of assays for biochemical markers of bone formation and resorption are being developed that promise to complement the densitometry measurements and imaging studies, providing an assessment of the rates of bone turnover and an earlier evaluation of the effects of therapy. In this review, emphasizing the recent literature, the major biochemical markers currently in use or under active investigation are described, and their application in a number of diseases of the skeleton including osteoporosis is evaluated.
Physiologic and biochemical aspects of skeletal muscle denervation and reinnervation
NASA Technical Reports Server (NTRS)
Max, S. R.; Mayer, R. F.
1984-01-01
Some of the physiologic and biochemical changes that occur in mammalian skeletal muscle following denervation and reinnervation are considered and some comparisons are made with changes observed following altered motor function. The nature of the trophic influence by which nerves control muscle properties are discussed, including the effects of choline acetyltransferase and acetylcholinesterase and the role of the acetylcholine receptor.
Wang, Ying; Ryu, Bum Han; Yoo, Wanki; Lee, Chang Woo; Kim, Kyeong Kyu; Lee, Jun Hyuck; Kim, T Doohun
2018-01-01
Lactic acid bacteria, which are involved in the fermentation of vegetables, meats, and dairy products, are widely used for the productions of small organic molecules and bioactive peptides. Here, a novel acetylesterase (LaAcE) from Lactobacillus acidophilus NCFM was identified, functionally characterized, immobilized, and subjected to site-directed mutagenesis for biotechnological applications. The enzymatic properties of LaAcE were investigated using biochemical and biophysical methods including native polyacrylamide gel electrophoresis, acetic acid release, biochemical assays, enzyme kinetics, and spectroscopic methods. Interestingly, LaAcE exhibited the ability to act on a broad range of substrates including glucose pentaacetate, glyceryl tributyrate, fish oil, and fermentation-related compounds. Furthermore, immobilization of LaAcE showed good recycling ability and high thermal stability compared with free LaAcE. A structural model of LaAcE was used to guide mutational analysis of hydrophobic substrate-binding region, which was composed of Leu 156 , Phe 164 , and Val 204 . Five mutants (L156A, F164A, V204A, L156A/F164A, and L156A/V204A) were generated and investigated to elucidate the roles of these hydrophobic residues in substrate specificity. This work provided valuable insights into the properties of LaAcE, and demonstrated that LaAcE could be used as a model enzyme of acetylesterase in lactic acid bacteria, making LaAcE a great candidate for industrial applications. Copyright © 2017 Elsevier B.V. All rights reserved.
In vivo Raman spectroscopy for biochemical monitoring of the human cervix throughout pregnancy.
O'Brien, Christine M; Vargis, Elizabeth; Rudin, Amy; Slaughter, James C; Thomas, Giju; Newton, J Michael; Reese, Jeff; Bennett, Kelly A; Mahadevan-Jansen, Anita
2018-05-01
The cervix must undergo significant biochemical remodeling to allow for successful parturition. This process is not fully understood, especially in instances of spontaneous preterm birth. In vivo Raman spectroscopy is an optical technique that can be used to investigate the biochemical composition of tissue longitudinally and noninvasively in human beings, and has been utilized to measure physiology and disease states in a variety of medical applications. The purpose of this study is to measure in vivo Raman spectra of the cervix throughout pregnancy in women, and to identify biochemical markers that change with the preparation for delivery and postpartum repair. In all, 68 healthy pregnant women were recruited. Raman spectra were measured from the cervix of each patient monthly in the first and second trimesters, weekly in the third trimester, and at the 6-week postpartum visit. Raman spectra were measured using an in vivo Raman system with an optical fiber probe to excite the tissue with 785 nm light. A spectral model was developed to highlight spectral regions that undergo the most changes throughout pregnancy, which were subsequently used for identifying Raman peaks for further analysis. These peaks were analyzed longitudinally to determine if they underwent significant changes over the course of pregnancy (P < .05). Finally, 6 individual components that comprise key biochemical constituents of the human cervix were measured to extract their contributions in spectral changes throughout pregnancy using a linear combination method. Patient factors including body mass index and parity were included as variables in these analyses. Raman peaks indicative of extracellular matrix proteins (1248 and 1254 cm -1 ) significantly decreased (P < .05), while peaks corresponding to blood (1233 and 1563 cm -1 ) significantly increased (P < .0005) in a linear manner throughout pregnancy. In the postpartum cervix, significant increases in peaks corresponding to actin (1003, 1339, and 1657 cm -1 ) and cholesterol (1447 cm -1 ) were observed when compared to late gestation, while signatures from blood significantly decreased. Postpartum actin signals were significantly higher than early pregnancy, whereas extracellular matrix proteins and water signals were significantly lower than early weeks of gestation. Parity had a significant effect on blood and extracellular matrix protein signals, with nulliparous patients having significant increases in blood signals throughout pregnancy, and higher extracellular matrix protein signals in early pregnancy compared to patients with prior pregnancies. Body mass index significantly affected actin signal contribution, with low body mass index patients showing decreasing actin contribution throughout pregnancy and high body mass index patients demonstrating increasing actin signals. Raman spectroscopy was successfully used to biochemically monitor cervical remodeling in pregnant women during prenatal visits. This foundational study has demonstrated sensitivity to known biochemical dynamics that occur during cervical remodeling, and identified patient variables that have significant effects on Raman spectra throughout pregnancy. Raman spectroscopy has the potential to improve our understanding of cervical maturation, and be used as a noninvasive preterm birth risk assessment tool to reduce the incidence, morbidity, and mortality caused by preterm birth. Copyright © 2018. Published by Elsevier Inc.
Hybrid pathwise sensitivity methods for discrete stochastic models of chemical reaction systems.
Wolf, Elizabeth Skubak; Anderson, David F
2015-01-21
Stochastic models are often used to help understand the behavior of intracellular biochemical processes. The most common such models are continuous time Markov chains (CTMCs). Parametric sensitivities, which are derivatives of expectations of model output quantities with respect to model parameters, are useful in this setting for a variety of applications. In this paper, we introduce a class of hybrid pathwise differentiation methods for the numerical estimation of parametric sensitivities. The new hybrid methods combine elements from the three main classes of procedures for sensitivity estimation and have a number of desirable qualities. First, the new methods are unbiased for a broad class of problems. Second, the methods are applicable to nearly any physically relevant biochemical CTMC model. Third, and as we demonstrate on several numerical examples, the new methods are quite efficient, particularly if one wishes to estimate the full gradient of parametric sensitivities. The methods are rather intuitive and utilize the multilevel Monte Carlo philosophy of splitting an expectation into separate parts and handling each in an efficient manner.
Activity-based protein profiling for biochemical pathway discovery in cancer
Nomura, Daniel K.; Dix, Melissa M.; Cravatt, Benjamin F.
2011-01-01
Large-scale profiling methods have uncovered numerous gene and protein expression changes that correlate with tumorigenesis. However, determining the relevance of these expression changes and which biochemical pathways they affect has been hindered by our incomplete understanding of the proteome and its myriad functions and modes of regulation. Activity-based profiling platforms enable both the discovery of cancer-relevant enzymes and selective pharmacological probes to perturb and characterize these proteins in tumour cells. When integrated with other large-scale profiling methods, activity-based proteomics can provide insight into the metabolic and signalling pathways that support cancer pathogenesis and illuminate new strategies for disease diagnosis and treatment. PMID:20703252
1977-07-01
F. Flora and R. C. Wiley, J . Food Scl., 39, 770 (1974). 2G. Rumpf, J . Mawson and H. Hansen, J . Sci. Food Agric., 23, 193 (1972). L Hough and J . K. N...Clamp, T . Bhatti and R. E. Chambers, Methods Biochem. Anal., 19, 229 (1971). 11 J . M. Richey, H. G. Richey, Jr. and R. Schraer, Analyt. Biochem., 9...C W Culpepper and C, A. Magoon, J . Agr. Res., 28, 403 (1924). -0. M Doty, G. M. Smith, J . R. Roach and J . T . Sullivan, Indiana Agr. Exp. Sta. Bull
The digital language of amino acids.
Kurić, L
2007-11-01
The subject of this paper is a digital approach to the investigation of the biochemical basis of genetic processes. The digital mechanism of nucleic acid and protein bio-syntheses, the evolution of biomacromolecules and, especially, the biochemical evolution of genetic language have been analyzed by the application of cybernetic methods, information theory and system theory, respectively. This paper reports the discovery of new methods for developing the new technologies in genetics. It is about the most advanced digital technology which is based on program, cybernetics and informational systems and laws. The results in the practical application of the new technology could be useful in bioinformatics, genetics, biochemistry, medicine and other natural sciences.
Adalsteinsson, David; McMillen, David; Elston, Timothy C
2004-03-08
Intrinsic fluctuations due to the stochastic nature of biochemical reactions can have large effects on the response of biochemical networks. This is particularly true for pathways that involve transcriptional regulation, where generally there are two copies of each gene and the number of messenger RNA (mRNA) molecules can be small. Therefore, there is a need for computational tools for developing and investigating stochastic models of biochemical networks. We have developed the software package Biochemical Network Stochastic Simulator (BioNetS) for efficiently and accurately simulating stochastic models of biochemical networks. BioNetS has a graphical user interface that allows models to be entered in a straightforward manner, and allows the user to specify the type of random variable (discrete or continuous) for each chemical species in the network. The discrete variables are simulated using an efficient implementation of the Gillespie algorithm. For the continuous random variables, BioNetS constructs and numerically solves the appropriate chemical Langevin equations. The software package has been developed to scale efficiently with network size, thereby allowing large systems to be studied. BioNetS runs as a BioSpice agent and can be downloaded from http://www.biospice.org. BioNetS also can be run as a stand alone package. All the required files are accessible from http://x.amath.unc.edu/BioNetS. We have developed BioNetS to be a reliable tool for studying the stochastic dynamics of large biochemical networks. Important features of BioNetS are its ability to handle hybrid models that consist of both continuous and discrete random variables and its ability to model cell growth and division. We have verified the accuracy and efficiency of the numerical methods by considering several test systems.
X-ray lasers for structural and dynamic biology
NASA Astrophysics Data System (ADS)
Spence, J. C. H.; Weierstall, U.; Chapman, H. N.
2012-10-01
Research opportunities and techniques are reviewed for the application of hard x-ray pulsed free-electron lasers (XFEL) to structural biology. These include the imaging of protein nanocrystals, single particles such as viruses, pump-probe experiments for time-resolved nanocrystallography, and snapshot wide-angle x-ray scattering (WAXS) from molecules in solution. The use of femtosecond exposure times, rather than freezing of samples, as a means of minimizing radiation damage is shown to open up new opportunities for the molecular imaging of biochemical reactions at room temperature in solution. This is possible using a ‘diffract-and-destroy’ mode in which the incident pulse terminates before radiation damage begins. Methods for delivering hundreds of hydrated bioparticles per second (in random orientations) to a pulsed x-ray beam are described. New data analysis approaches are outlined for the correlated fluctuations in fast WAXS, for protein nanocrystals just a few molecules on a side, and for the continuous x-ray scattering from a single virus. Methods for determining the orientation of a molecule from its diffraction pattern are reviewed. Methods for the preparation of protein nanocrystals are also reviewed. New opportunities for solving the phase problem for XFEL data are outlined. A summary of the latest results is given, which now extend to atomic resolution for nanocrystals. Possibilities for time-resolved chemistry using fast WAXS (solution scattering) from mixtures is reviewed, toward the general goal of making molecular movies of biochemical processes.
Maliken, Bryan D; Avrin, William F; Nelson, James E; Mooney, Jody; Kumar, Sankaran; Kowdley, Kris V
2012-01-01
There is an ongoing clinical need for novel methods to measure hepatic iron content (HIC) noninvasively. Both magnetic resonance imaging (MRI) and superconducting quantum interference device (SQUID) methods have previously shown promise for estimation of HIC, but these methods can be expensive and are not widely available. Room-temperature susceptometry (RTS) represents an inexpensive alternative and was previously found to be strongly correlated with HIC estimated by SQUID measurements among patients with transfusional iron overload related to thalassemia. The goal of the current study was to examine the relationship between RTS and biochemical HIC measured in liver biopsy specimens in a more varied patient cohort. Susceptometry was performed in a diverse group of patients with hyperferritinemia due to hereditary hemochromatosis (HHC) (n = 2), secondary iron overload (n = 3), nonalcoholic fatty liver disease (NAFLD) (n = 2), and chronic viral hepatitis (n = 3) within one month of liver biopsy in the absence of iron depletion therapy. The correlation coefficient between HIC estimated by susceptometry and by biochemical iron measurement in liver tissue was 0.71 (p = 0.022). Variance between liver iron measurement and susceptometry measurement was primarily related to reliance on the patient's body-mass index (BMI) to estimate the magnetic susceptibility of tissue overlying the liver. We believe RTS holds promise for noninvasive measurement of HIC. Improved measurement techniques, including more accurate overlayer correction, may further improve the accuracy of liver susceptometry in patients with liver disease.
Biochemical Phenotypes to Discriminate Microbial Subpopulations and Improve Outbreak Detection
Galar, Alicia; Kulldorff, Martin; Rudnick, Wallis; O'Brien, Thomas F.; Stelling, John
2013-01-01
Background Clinical microbiology laboratories worldwide constitute an invaluable resource for monitoring emerging threats and the spread of antimicrobial resistance. We studied the growing number of biochemical tests routinely performed on clinical isolates to explore their value as epidemiological markers. Methodology/Principal Findings Microbiology laboratory results from January 2009 through December 2011 from a 793-bed hospital stored in WHONET were examined. Variables included patient location, collection date, organism, and 47 biochemical and 17 antimicrobial susceptibility test results reported by Vitek 2. To identify biochemical tests that were particularly valuable (stable with repeat testing, but good variability across the species) or problematic (inconsistent results with repeat testing), three types of variance analyses were performed on isolates of K. pneumonia: descriptive analysis of discordant biochemical results in same-day isolates, an average within-patient variance index, and generalized linear mixed model variance component analysis. Results: 4,200 isolates of K. pneumoniae were identified from 2,485 patients, 32% of whom had multiple isolates. The first two variance analyses highlighted SUCT, TyrA, GlyA, and GGT as “nuisance” biochemicals for which discordant within-patient test results impacted a high proportion of patient results, while dTAG had relatively good within-patient stability with good heterogeneity across the species. Variance component analyses confirmed the relative stability of dTAG, and identified additional biochemicals such as PHOS with a large between patient to within patient variance ratio. A reduced subset of biochemicals improved the robustness of strain definition for carbapenem-resistant K. pneumoniae. Surveillance analyses suggest that the reduced biochemical profile could improve the timeliness and specificity of outbreak detection algorithms. Conclusions The statistical approaches explored can improve the robust recognition of microbial subpopulations with routinely available biochemical test results, of value in the timely detection of outbreak clones and evolutionarily important genetic events. PMID:24391936
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pisansky, Thomas M., E-mail: pisansky.thomas@mayo.edu; Agrawal, Shree; Hamstra, Daniel A.
Purpose: To determine whether a dose-response relationship exists for salvage radiation therapy (RT) of biochemical failure after prostatectomy for prostate cancer. Methods and Materials: Individual data from 1108 patients who underwent salvage RT at 10 academic centers were pooled. The cohort was enriched for selection criteria more likely associated with tumor recurrence in the prostate bed (margin positive and pre-RT prostate-specific antigen [PSA] level of ≤2.0 ng/mL) and without the confounding of planned androgen suppression. The cumulative incidence of biochemical failure and distant metastasis over time was computed, and competing risks hazard regression models were used to investigate the association betweenmore » potential predictors and these outcomes. The association of radiation dose with outcomes was the primary focus. Results: With a 65.2-month follow-up duration, the 5- and 10-year estimates of freedom from post-RT biochemical failure (PSA level >0.2 ng/mL and rising) was 63.5% and 49.8%, respectively, and the cumulative incidence of distant metastasis was 12.4% by 10 years. A Gleason score of ≥7, higher pre-RT PSA level, extraprostatic tumor extension, and seminal vesicle invasion were associated with worse biochemical failure and distant metastasis outcomes. A salvage radiation dose of ≥66.0 Gy was associated with a reduced cumulative incidence of biochemical failure, but not of distant metastasis. Conclusions: The use of salvage radiation doses of ≥66.0 Gy are supported by evidence presented in the present multicenter pooled analysis of individual patient data. The observational reporting method, limited sample size, few distant metastasis events, modest follow-up duration, and elective use of salvage therapy might have diminished the opportunity to identify an association between the radiation dose and this endpoint.« less
2012-02-24
AND SUBTITLE Detection of Biochemical Pathogens, Laser Stand-off Spectroscopy, Quantum Coherence, and Many Body Quantum Optics 6. AUTHORS Marian O...Maximum 200 words) Results of our earlier research in the realm of quantum optics were extended in order to solve the challenging technical problems of...efficient methods of generating UV light via quantum coherence. 14. SUBJECT TERMS Quantum coherence, quantum optics, lasers 15. NUMBER OF PAGES 15
Logic-Based Models for the Analysis of Cell Signaling Networks†
2010-01-01
Computational models are increasingly used to analyze the operation of complex biochemical networks, including those involved in cell signaling networks. Here we review recent advances in applying logic-based modeling to mammalian cell biology. Logic-based models represent biomolecular networks in a simple and intuitive manner without describing the detailed biochemistry of each interaction. A brief description of several logic-based modeling methods is followed by six case studies that demonstrate biological questions recently addressed using logic-based models and point to potential advances in model formalisms and training procedures that promise to enhance the utility of logic-based methods for studying the relationship between environmental inputs and phenotypic or signaling state outputs of complex signaling networks. PMID:20225868
Reddy, K. S.; Prabhakaran, D.; Chaturvedi, V.; Jeemon, P.; Thankappan, K. R.; Ramakrishnan, L.; Mohan, B. V. M.; Pandav, C. S.; Ahmed, F. U.; Joshi, P. P.; Meera, R.; Amin, R. B.; Ahuja, R. C.; Das, M. S.; Jaison, T. M.
2006-01-01
OBJECTIVE: To establish a surveillance network for cardiovascular diseases (CVD) risk factors in industrial settings and estimate the risk factor burden using standardized tools. METHODS: We conducted a baseline cross-sectional survey (as part of a CVD surveillance programme) of industrial populations from 10 companies across India, situated in close proximity to medical colleges that served as study centres. The study subjects were employees (selected by age and sex stratified random sampling) and their family members. Information on behavioural, clinical and biochemical determinants was obtained through standardized methods (questionnaires, clinical measurements and biochemical analysis). Data collation and analyses were done at the national coordinating centre. FINDINGS: We report the prevalence of CVD risk factors among individuals aged 20-69 years (n = 19 973 for the questionnaire survey, n = 10 442 for biochemical investigations); mean age was 40 years. The overall prevalence of most risk factors was high, with 50.9% of men and 51.9% of women being overweight, central obesity was observed among 30.9% of men and 32.8% of women, and 40.2% of men and 14.9% of women reported current tobacco use. Self-reported prevalence of diabetes (5.3%) and hypertension (10.9%) was lower than when measured clinically and biochemically (10.1% and 27.7%, respectively). There was marked heterogeneity in the prevalence of risk factors among the study centres. CONCLUSION: There is a high burden of CVD risk factors among industrial populations across India. The surveillance system can be used as a model for replication in India as well as other developing countries. PMID:16799730
Method 1200: Analytical Protocol for Non-Typhoidal Salmonella in Drinking Water and Surface Water
Method 1200 is used for identification, confirmation and quantitation of non-typhoidal Salmonella in water samples, using selective and non-selective media followed by biochemical and serological confirmation.
Biotinidase deficiency: Genotype-biochemical phenotype association in Brazilian patients
Borsatto, Taciane; Sperb-Ludwig, Fernanda; Lima, Samyra E.; S. Carvalho, Maria R.; S. Fonseca, Pablo A.; S. Camelo, José; M. Ribeiro, Erlane; F. V. de Medeiros, Paula; M. Lourenço, Charles; F. M. de Souza, Carolina; Boy, Raquel; Félix, Têmis M.; M. Bittar, Camila; L. C. Pinto, Louise; C. Neto, Eurico; J. Blom, Henk; D. Schwartz, Ida V.
2017-01-01
Introduction The association between the BTD genotype and biochemical phenotype [profound biotinidase deficiency (BD), partial BD or heterozygous activity] is not always consistent. This study aimed to investigate the genotype-biochemical phenotype association in patients with low biotinidase activity. Methods All exons, the 5'UTR and the promoter of the BTD gene were sequenced in 72 Brazilian individuals who exhibited low biotinidase activity. For each patient, the expected biochemical phenotype based on the known genotype was compared with the observed biochemical phenotype. Additional non-genetic factors that could affect the biotinidase activity were also analysed. Results Most individuals were identified by neonatal screening (n = 66/72). When consecutive results for the same patient were compared, age, prematurity and neonatal jaundice appeared to affect the level of biotinidase activity. The biochemical phenotype at the time of the second blood collection changed in 11/22 patients compared to results from the first sample. Three novel variants were found: c.1337T>C (p.L446P), c.1466A>G (p.N489S) and c.962G>A (p.W321*). Some patients with the same genotype presented different biochemical phenotypes. The expected and observed biochemical phenotypes agreed in 68.5% of cases (concordant patients). The non-coding variants c.-183G>A, c.-315A>G and c.-514C>T were present in heterozygosis in 5/17 discordant patients. In addition, c.-183G>A and c.-514C>T were also present in 10/37 concordant patients. Conclusions The variants found in the promoter region do not appear to have a strong impact on biotinidase activity. Since there is a disparity between the BTD genotype and biochemical phenotype, and biotinidase activity may be affected by both genetic and non-genetic factors, we suggest that the diagnosis of BD should be based on more than one measurement of plasma biotinidase activity. DNA analysis can be of additional relevance to differentiate between partial BD and heterozygosity. PMID:28498829
Dental radiographic indicators, a key to age estimation
Panchbhai, AS
2011-01-01
Objective The present review article is aimed at describing the radiological methods utilized for human age identification. Methods The application and importance of radiological methods in human age assessment was discussed through the literature survey. Results Following a literature search, 46 articles were included in the study and the relevant information is depicted in the article. Dental tissue is often preserved indefinitely after death. Implementation of radiography is based on the assessment of the extent of calcification of teeth and in turn the degree of formation of crown and root structures, along with the sequence and the stages of eruption. Several radiological techniques can be used to assist in both individual and general identification, including determination of gender, ethnic group and age. The radiographic method is a simpler and cheaper method of age identification compared with histological and biochemical methods. Radiographic and tomographic images have become an essential aid for human identification in forensic dentistry, particularly with the refinement of techniques and the incorporation of information technology resources. Conclusion Based on an appropriate knowledge of the available methods, forensic dentists can choose the most appropriate since the validity of age estimation crucially depends on the method used and its proper application. The multifactorial approach will lead to optimum age assessment. The legal requirements also have to be considered. PMID:21493876
Biochemical mechanisms of cisplatin cytotoxicity.
Cepeda, Victoria; Fuertes, Miguel A; Castilla, Josefina; Alonso, Carlos; Quevedo, Celia; Pérez, Jose M
2007-01-01
Since the discovery by Rosenberg and collaborators of the antitumor activity of cisplatin 35 years ago, three platinum antitumor drugs (cisplatin, carboplatin and oxaliplatin) have enjoyed a huge clinical and commercial hit. Ever since the initial discovery of the anticancer activity of cisplatin, major efforts have been devoted to elucidate the biochemical mechanisms of antitumor activity of cisplatin in order to be able to rationally design novel platinum based drugs with superior pharmacological profiles. In this report we attempt to provide a current picture of the known facts pertaining to the mechanism of action of the drug, including those involved in drug uptake, DNA damage signals transduction, and cell death through apoptosis or necrosis. A deep knowledge of the biochemical mechanisms, which are triggered in the tumor cell in response to cisplatin injury not only may lead to the design of more efficient platinum antitumor drugs but also may provide new therapeutic strategies based on the biochemical modulation of cisplatin activity.
Vitreous humour - routine or alternative material for analysis in forensic medicine.
Markowska, Joanna; Szopa, Monika; Zawadzki, Marcin; Piekoszewski, Wojciech
2017-01-01
Biological materials used in toxicological analyses in forensic medicine traditionally include blood, urine and vitreous humour. Forensic use of the vitreous body is mostly due to the need to assess the endogenous concentration of ethyl alcohol in the process of human body decomposition. The vitreous body is an underestimated biological material, even though its biochemical properties and anatomical location make it suitable for specific forensic toxicology tests as a reliable material for the preparation of forensic expert opinions. Based on the available literature the paper gathers information on the biochemical structure of the vitreous body, ways to secure the material after collection and its use in postmortem diagnostics. Specific applications of the vitreous humour for biochemical and toxicological tests are discussed, with a focus on its advantages and limitations in forensic medical assessment which are attributable to its biochemical properties, anatomical location and limited scientific studies on the distribution of xenobiotics in the vitreous body.
NASA Astrophysics Data System (ADS)
Inisheva, L. I.; Szajdak, L.; Sergeeva, M. A.
2016-04-01
The biological activity in oligotrophic peatlands at the margins of the Vasyugan Mire has been studied. It is shown found that differently directed biochemical processes manifest themselves in the entire peat profile down to the underlying mineral substrate. Their activity is highly variable. It is argued that the notion about active and inert layers in peat soils is only applicable for the description of their water regime. The degree of the biochemical activity is specified by the physical soil properties. As a result of the biochemical processes, a micromosaic aerobic-anaerobic medium is developed under the surface waterlogged layer of peat deposits. This layer contains the gas phase, including oxygen. It is concluded that the organic and mineral parts of peat bogs represent a single functional system of a genetic peat profile with a clear record of the history of its development.
Moslemi, Mohammad Kazem; Saghafi, Hossein; Joorabchin, Seyed Mohammad Amin
2011-01-01
Purpose The aim of this study was to evaluate the biochemical stone composition in general population of Qom province, central Iran, and its relationship with high tap water hardness. Materials and methods In a prospective study, from March 2008 to July 2011, biochemical analysis of urinary stones in patients living in Qom province for at least 5 years was performed. Stones were retrieved by spontaneous passage, endoscopic or open surgery, and after extracorporeal shockwave lithotripsy. Demographic findings and the drinking water supply of patients were evaluated and compared with biochemical stone analysis. Results Stone analysis was performed in 255 patients. The most dominant composition of urinary stones was calcium oxalate (73%), followed by uric acid (24%), ammonium urate (2%), and cystine (1%). The peak incidence of urinary stone was in patients in their forties. Overall male to female ratio was 4.93:1. Conclusion The dominant stone composition in inhabitants of central Iran, where tap water hardness is high, was calcium oxalate stones. On the basis of this study, biochemical urinary stone composition of Qom does not differ from other regions of Iran with lower water hardness. PMID:22163171
Biosensors and bioelectronics on smartphone for portable biochemical detection.
Zhang, Diming; Liu, Qingjun
2016-01-15
Smartphone has been widely integrated with sensors, such as test strips, sensor chips, and hand-held detectors, for biochemical detections due to its portability and ubiquitous availability. Utilizing built-in function modules, smartphone is often employed as controller, analyzer, and displayer for rapid, real-time, and point-of-care monitoring, which can significantly simplify design and reduce cost of the detecting systems. This paper presents a review of biosensors and bioelectronics on smartphone for portable biochemical detections. The biosensors and bioelectronics based on smartphone can mainly be classified into biosensors using optics, surface plasmon resonance, electrochemistry, and near-field communication. The developments of these biosensors and bioelectronics on smartphone are reviewed along with typical biochemical detecting cases. Sensor strategies, detector attachments, and coupling methods are highlighted to show designs of the compact, lightweight, and low-cost sensor systems. The performances and advantages of these designs are introduced with their applications in healthcare diagnosis, environment monitoring, and food evaluation. With advances in micro-manufacture, sensor technology, and miniaturized electronics, biosensor and bioelectronic devices on smartphone can be used to perform biochemical detections as common and convenient as electronic tag readout in foreseeable future. Copyright © 2015 Elsevier B.V. All rights reserved.
Use of fibroblast growth factor 2 for expansion of chondrocytes and tissue engineering
NASA Technical Reports Server (NTRS)
Vunjak-Novakovic, Gordana (Inventor); Martin, Ivan (Inventor); Freed, Lisa E. (Inventor); Langer, Robert (Inventor)
2003-01-01
The present invention provides an improved method for expanding cells for use in tissue engineering. In particular the method provides specific biochemical factors to supplement cell culture medium during the expansion process in order to reproduce events occurring during embryonic development with the goal of regenerating tissue equivalents that resemble natural tissues both structurally and functionally. These specific biochemical factors improve proliferation of the cells and are capable of de-differentiation mature cells isolated from tissue so that the differentiation potential of the cells is preserved. The bioactive molecules also maintain the responsiveness of the cells to other bioactive molecules. Specifically, the invention provides methods for expanding chondrocytes in the presence of fibroblast growth factor 2 for use in regeneration of cartilage tissue.
Multiplexed 3D FRET imaging in deep tissue of live embryos
Zhao, Ming; Wan, Xiaoyang; Li, Yu; Zhou, Weibin; Peng, Leilei
2015-01-01
Current deep tissue microscopy techniques are mostly restricted to intensity mapping of fluorophores, which significantly limit their applications in investigating biochemical processes in vivo. We present a deep tissue multiplexed functional imaging method that probes multiple Förster resonant energy transfer (FRET) sensors in live embryos with high spatial resolution. The method simultaneously images fluorescence lifetimes in 3D with multiple excitation lasers. Through quantitative analysis of triple-channel intensity and lifetime images, we demonstrated that Ca2+ and cAMP levels of live embryos expressing dual FRET sensors can be monitored simultaneously at microscopic resolution. The method is compatible with a broad range of FRET sensors currently available for probing various cellular biochemical functions. It opens the door to imaging complex cellular circuitries in whole live organisms. PMID:26387920
Maximizing the Biochemical Resolving Power of Fluorescence Microscopy
Esposito, Alessandro; Popleteeva, Marina; Venkitaraman, Ashok R.
2013-01-01
Most recent advances in fluorescence microscopy have focused on achieving spatial resolutions below the diffraction limit. However, the inherent capability of fluorescence microscopy to non-invasively resolve different biochemical or physical environments in biological samples has not yet been formally described, because an adequate and general theoretical framework is lacking. Here, we develop a mathematical characterization of the biochemical resolution in fluorescence detection with Fisher information analysis. To improve the precision and the resolution of quantitative imaging methods, we demonstrate strategies for the optimization of fluorescence lifetime, fluorescence anisotropy and hyperspectral detection, as well as different multi-dimensional techniques. We describe optimized imaging protocols, provide optimization algorithms and describe precision and resolving power in biochemical imaging thanks to the analysis of the general properties of Fisher information in fluorescence detection. These strategies enable the optimal use of the information content available within the limited photon-budget typically available in fluorescence microscopy. This theoretical foundation leads to a generalized strategy for the optimization of multi-dimensional optical detection, and demonstrates how the parallel detection of all properties of fluorescence can maximize the biochemical resolving power of fluorescence microscopy, an approach we term Hyper Dimensional Imaging Microscopy (HDIM). Our work provides a theoretical framework for the description of the biochemical resolution in fluorescence microscopy, irrespective of spatial resolution, and for the development of a new class of microscopes that exploit multi-parametric detection systems. PMID:24204821
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vance, Waseet; Tucker, Susan L.; Crevoisier, Renaud de
2007-03-01
Purpose: To determine the value of a 2-year post-radiotherapy (RT) prostate biopsy for predicting eventual biochemical failure in patients who were treated for localized prostate cancer. Methods and Materials: This study comprised 164 patients who underwent a planned 2-year post-RT prostate biopsy. The independent prognostic value of the biopsy results for forecasting eventual biochemical outcome and overall survival was tested with other factors (the Gleason score, 1992 American Joint Committee on Cancer tumor stage, pretreatment prostate-specific antigen level, risk group, and RT dose) in a multivariate analysis. The current nadir + 2 (CN + 2) definition of biochemical failure wasmore » used. Patients with rising prostate-specific antigen (PSA) or suspicious digital rectal examination before the biopsy were excluded. Results: The biopsy results were normal in 78 patients, scant atypical and malignant cells in 30, carcinoma with treatment effect in 43, and carcinoma without treatment effect in 13. Using the CN + 2 definition, we found a significant association between biopsy results and eventual biochemical failure. We also found that the biopsy status provides predictive information independent of the PSA status at the time of biopsy. Conclusion: A 2-year post-RT prostate biopsy may be useful for forecasting CN + 2 biochemical failure. Posttreatment prostate biopsy may be useful for identifying patients for aggressive salvage therapy.« less
Hogg, Jeannette; Diaz, Alejandro; Cid, Margareth Del; Mueller, Charles; Lipman, Elizabeth Grace; Cheruvu, Sunita; Chiu, Ya-lin; Vogiatzi, Maria; Nimkarn, Saroj
2013-01-01
Background Forty-three percent of New York City's (NYC) school-age children are overweight or obese, placing them at risk for heart disease and type 2 diabetes mellitus (T2DM). Objective The objective of this study was to determine if an intensive after-school dance and lifestyle education program would reduce risk factors for heart disease, T2DM, and improve lifestyle choices. Subjects Subject include 64 fourth- and fifth-grade students at an elementary school in NYC. Methods Students received freestyle dance and lifestyle classes for 16 weeks and were evaluated for changes in body composition, endurance, biochemical measurements, and lifestyle choices. Results Significant improvements in BMI percentiles were found among children in the overweight and obese categories as well as in endurance and biochemical measurements that reflect heart disease and diabetes risk. Improvement was also reported in lifestyle choices. Conclusion An intensive after-school dance and lifestyle education program can reduce risk factors for heart disease and T2DM and improve lifestyle choices among elementary school children. PMID:22876547
Computational analysis of the roles of biochemical reactions in anomalous diffusion dynamics
NASA Astrophysics Data System (ADS)
Naruemon, Rueangkham; Charin, Modchang
2016-04-01
Most biochemical processes in cells are usually modeled by reaction-diffusion (RD) equations. In these RD models, the diffusive process is assumed to be Gaussian. However, a growing number of studies have noted that intracellular diffusion is anomalous at some or all times, which may result from a crowded environment and chemical kinetics. This work aims to computationally study the effects of chemical reactions on the diffusive dynamics of RD systems by using both stochastic and deterministic algorithms. Numerical method to estimate the mean-square displacement (MSD) from a deterministic algorithm is also investigated. Our computational results show that anomalous diffusion can be solely due to chemical reactions. The chemical reactions alone can cause anomalous sub-diffusion in the RD system at some or all times. The time-dependent anomalous diffusion exponent is found to depend on many parameters, including chemical reaction rates, reaction orders, and chemical concentrations. Project supported by the Thailand Research Fund and Mahidol University (Grant No. TRG5880157), the Thailand Center of Excellence in Physics (ThEP), CHE, Thailand, and the Development Promotion of Science and Technology.
Microfabricated Electrochemical Cell-Based Biosensors for Analysis of Living Cells In Vitro
Wang, Jun; Wu, Chengxiong; Hu, Ning; Zhou, Jie; Du, Liping; Wang, Ping
2012-01-01
Cellular biochemical parameters can be used to reveal the physiological and functional information of various cells. Due to demonstrated high accuracy and non-invasiveness, electrochemical detection methods have been used for cell-based investigation. When combined with improved biosensor design and advanced measurement systems, the on-line biochemical analysis of living cells in vitro has been applied for biological mechanism study, drug screening and even environmental monitoring. In recent decades, new types of miniaturized electrochemical biosensor are emerging with the development of microfabrication technology. This review aims to give an overview of the microfabricated electrochemical cell-based biosensors, such as microelectrode arrays (MEA), the electric cell-substrate impedance sensing (ECIS) technique, and the light addressable potentiometric sensor (LAPS). The details in their working principles, measurement systems, and applications in cell monitoring are covered. Driven by the need for high throughput and multi-parameter detection proposed by biomedicine, the development trends of electrochemical cell-based biosensors are also introduced, including newly developed integrated biosensors, and the application of nanotechnology and microfluidic technology. PMID:25585708
Acupuncture therapy in treating migraine: results of a magnetic resonance spectroscopy imaging study
Gu, Tao; Lin, Lei; Jiang, Yun; Chen, Juan; D’Arcy, Ryan CN; Chen, Min; Song, Xiaowei
2018-01-01
Background Acupuncture has been proven to be effective as an alternative therapy in treating migraine, but the pathophysiological mechanisms of the treatment remain unclear. This study investigated possible neurochemical responses to acupuncture treatment. Patients and methods Proton magnetic resonance spectroscopy imaging was used to investigate biochemical levels pre- and post-acupuncture treatment. Participants (N=45) included subjects diagnosed with: 1) migraine without aura; 2) cervicogenic headache; and 3) healthy controls. Participants in the two patient groups received verum acupuncture using acupoints that target migraine without aura but not cervicogenic headache, while the healthy controls received a sham treatment. All participants had magnetic resonance spectroscopy scans before and after the acupuncture therapy. Levels of brain metabolites were examined in relation to clinical headache assessment scores. Results A significant increase in N-acetylaspartate/creatine was observed in bilateral thalamus in migraine without aura after the acupuncture treatment, which was significantly correlated with the headache intensity score. Conclusion The data demonstrate brain biochemical changes underlying the effect of acupuncture treatment of migraine. PMID:29740217
Glycosidases induced in Aspergillus tamarii. Secreted alpha-D-galactosidase and beta-D-mannanase.
Civas, A; Eberhard, R; Le Dizet, P; Petek, F
1984-01-01
An alpha-D-galactosidase (EC 3.2.1.22) and a beta-D-mannanase (EC 3.2.1.78), which were secreted into the growth medium when Aspergillus tamarii was cultivated in the presence of galactomannan, were purified by a procedure including chromatography on hydroxyapatite and DEAE-cellulose columns. Each of these enzymes showed a single protein band, corresponding to their respective activities, on polyacrylamide-gel electrophoresis. Both enzymes were shown to be glycoproteins containing N-acetylglucosamine, mannose and galactose, with molar proportions of 1:6:1.5 for alpha-D-galactosidase and 1:13:8 for beta-D-mannanase. Mr values as determined by polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate and by the electrophoretic method of Hedrick & Smith [(1968) Arch. Biochem. Biophys. 126, 155-164] were 56000 and 53000 respectively. The alpha-D-galactosidase differed markedly from the mycelial forms I and II studied in the preceding paper [Civas, Eberhard, Le Dizet & Petek (1984) Biochem. J. 219, 849-855] with regard to both its kinetic and structural properties. Images Fig. 1. PMID:6331399
Osipiuk, Jerzy; Mulligan, Rory; Bargassa, Monireh; Hamilton, John E.; Cunningham, Mark A.; Joachimiak, Andrzej
2012-01-01
The crystal structure of SO1698 protein from Shewanella oneidensis was determined by a SAD method and refined to 1.57 Å. The structure is a β sandwich that unexpectedly consists of two polypeptides; the N-terminal fragment includes residues 1–116, and the C-terminal one includes residues 117–125. Electron density also displayed the Lys-98 side chain covalently linked to Asp-116. The putative active site residues involved in self-cleavage were identified; point mutants were produced and characterized structurally and in a biochemical assay. Numerical simulations utilizing molecular dynamics and hybrid quantum/classical calculations suggest a mechanism involving activation of a water molecule coordinated by a catalytic aspartic acid. PMID:22493430
Study design of the Maycoba Project: obesity and diabetes in Mexican Pimas.
Urquidez-Romero, Rene; Esparza-Romero, Julian; Chaudhari, Lisa S; Begay, R Cruz; Giraldo, Mario; Ravussin, Eric; Knowler, William C; Hanson, Robert L; Bennett, Peter H; Schulz, Leslie O; Valencia, Mauro E
2014-05-01
To focus on the rationale and methods of the Maycoba Project. Study population included Mexican Pima Indians (MPI) and Blancos aged ≥20-years, living in the village of Maycoba and surrounding area. Surveys in 1995 and 2010 included a medical history, biochemical and anthropomet- ric measurements. Additionally, socio- economic, physical activity, and dietary interviews were conducted. The 2010 study incorporated investigations on type 2 diabetes (T2D) and obesity-associated genetic alleles and human-envi- ronment changes. The study results are limited to demographic data and description of the eligible and ex- amined sample. This study may yield important information on T2D and obesity etiology in a traditional population exposed to environmental changes.
NASA Astrophysics Data System (ADS)
Verrelst, Jochem; Malenovský, Zbyněk; Van der Tol, Christiaan; Camps-Valls, Gustau; Gastellu-Etchegorry, Jean-Philippe; Lewis, Philip; North, Peter; Moreno, Jose
2018-06-01
An unprecedented spectroscopic data stream will soon become available with forthcoming Earth-observing satellite missions equipped with imaging spectroradiometers. This data stream will open up a vast array of opportunities to quantify a diversity of biochemical and structural vegetation properties. The processing requirements for such large data streams require reliable retrieval techniques enabling the spatiotemporally explicit quantification of biophysical variables. With the aim of preparing for this new era of Earth observation, this review summarizes the state-of-the-art retrieval methods that have been applied in experimental imaging spectroscopy studies inferring all kinds of vegetation biophysical variables. Identified retrieval methods are categorized into: (1) parametric regression, including vegetation indices, shape indices and spectral transformations; (2) nonparametric regression, including linear and nonlinear machine learning regression algorithms; (3) physically based, including inversion of radiative transfer models (RTMs) using numerical optimization and look-up table approaches; and (4) hybrid regression methods, which combine RTM simulations with machine learning regression methods. For each of these categories, an overview of widely applied methods with application to mapping vegetation properties is given. In view of processing imaging spectroscopy data, a critical aspect involves the challenge of dealing with spectral multicollinearity. The ability to provide robust estimates, retrieval uncertainties and acceptable retrieval processing speed are other important aspects in view of operational processing. Recommendations towards new-generation spectroscopy-based processing chains for operational production of biophysical variables are given.
Lötsch, Jörn; Kringel, Dario
2018-06-01
The novel research area of functional genomics investigates biochemical, cellular, or physiological properties of gene products with the goal of understanding the relationship between the genome and the phenotype. These developments have made analgesic drug research a data-rich discipline mastered only by making use of parallel developments in computer science, including the establishment of knowledge bases, mining methods for big data, machine-learning, and artificial intelligence, (Table ) which will be exemplarily introduced in the following. © 2018 The Authors Clinical Pharmacology & Therapeutics published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.
Organic molecules as chemical fossils - The molecular fossil record
NASA Technical Reports Server (NTRS)
Eglinton, G.
1983-01-01
The study of biochemical clues to the early earth and the origin of life is discussed. The methods used in such investigation are described, including the extraction, fractionation, and analysis of geolipids and the analysis of kerogen. The occurrence of molecular fossils in the geological record is examined, discussing proposed precursor-product relationships and the molecular assessment of deep sea sediments, ancient sediments, and crude petroleums. Alterations in the molecular record due to diagenesis and catagenesis are considered, and the use of microbial lipids as molecular fossils is discussed. The results of searches for molecular fossils in Precambrian sediments are assessed.
Erythrocyte-derived optical nano-vesicles as theranostic agents
NASA Astrophysics Data System (ADS)
Mac, Jenny T.; Nunez, Vicente; Bahmani, Baharak; Guerrero, Yadir; Tang, Jack; Vullev, Valentine I.; Anvari, Bahman
2015-07-01
We have engineered nano-vesicles, derived from erythrocytes, which can be doped with various near infrared (NIR) organic chromophores, including the FDA-approved indocyanine green (ICG). We refer to these vesicles as NIR erythrocyte-mimicking transducers (NETS) since in response to NIR photo-excitation they can generate heat or emit fluorescent light. Using biochemical methods based on reduction amination, we have functionalized the surface of NET with antibodies to target specific biomolecules. We present results that demonstrate the effectiveness of NETs in targeted imaging of cancer cells that over-express the human epidermal growth factor receptor-2 (HER2).
Serezhnikova, N B; Pogodina, L S; Lipina, T V; Trofimova, N N; Gurieva, T S; Zak, P P
2017-07-01
The effect of everyday blue light (λ = 440-460 nm) on mitochondria of the retinal pigment epithelium of different age groups of Japanese quail was studied using electron microscopy, morphometric methods, and biochemical analysis. We have found a significant increase in the number of mitochondria, including those modified, mainly in young birds. In addition, cell metabolic activity increased in response to blue lighting. These changes are assumed to reflect an adaptive response of mitochondria aimed at neutralizing the phototoxic effect of blue light caused by accumulation of lipofuscin granules.
Alekish, Myassar O.; Talafha, Abdelsalam Q; Alshehabat, Musa A; Ismail, Zuhair A Bani
Neospora caninum is an important cause of abortion in dairy cattle. The general health of affected cows has not been investigated before. Therefore, the main objective of this study was to identify possible relationships between certain metabolic diseases and selected serum biochemical parameters in seropositive dairy cows against N. caninum antibodies in different stages of lactation. The study was carried out using 72 N. caninum seropositive cows and 61 seronegative dairy cows (control). Serum from all cows was tested to determine their N. caninum status (seropositive vs seronegative) using commercially available indirect enzyme-linked immunosorbent assay test kit (iELISA). In addition, serum biochemical parameters including beta-hydroxybutyrate (BHB), glucose, creatinine, blood urea nitrogen, total protein, albumin, alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH) and gamma-glutamyltranspeptidase (GGT) were determined using routine laboratory methods. The stage of lactation was obtained at the time of sampling from farm records. Student independent t-test showed that there was a significant difference in the serum concentrations of BHB, AST, ALT, and LDH between seropositive and seronegative cows. There was no significant association between seropositivity and the stage of lactation. However, multivariable logistic regression analysis showed that there was a strong association between seropositivity and BHB concentrations. Results of this study indicate a possible relationship between N. caninum seropositivity and certain metabolic diseases such as ketosis and fatty liver syndrome in dairy cows.
Evaluation of gradual occlusion of the caudal vena cava in clinically normal dogs.
Peacock, John T; Fossum, Theresa W; Bahr, Anne M; Miller, Matthew W; Edwards, John F
2003-11-01
To devise a technique for gradual occlusion of the caudal vena cava in dogs and determine effects of complete occlusion of the caudal vena cava. 8 mixed-breed hounds that weighed between 25 and 30 kg. Baseline evaluation of dogs included serum biochemical analyses and determination of glomerular filtration rate (GFR) with dynamic renal scintigraphy and plasma clearance analysis. An occluder was placed around the vena cava in the region cranial to the renal veins. The occluder was attached to a vascular access port. The vena cava was gradually occluded over 2 weeks. The GFR was measured every 2 weeks after surgery, and venograms were performed every 3 weeks after surgery. Blood samples were collected every 48 hours for the first week and then weekly thereafter to measure BUN and creatinine concentrations and activities of alanine transaminase, alkaline phosphatase, and creatinine kinase. Dogs were euthanatized 6 weeks after surgery, and tissues were submitted for histologic examination. The GFR and biochemical data were compared with baseline values. Gradual occlusion of the caudal vena cava was easily and consistently performed with this method, and adverse clinical signs were not detected. Formation of collateral vessels allowed overall GFR to remain constant despite a decrease in function of the left kidney. Measured biochemical values did not deviate from reference ranges. Gradual occlusion of the caudal vena cava may allow removal of adrenal gland tumors with vascular invasion that would otherwise be difficult or impossible to resect.
Shawaf, Turke; El-Deeb, Wael; Hussen, Jamal; Hendi, Mahmoud; Al-Bulushi, Shahab
2018-01-01
Aim: Recently, the complementary therapies such as cupping and acupuncture are being used in veterinary medicine. This research was carried out to determine the effects of wet cupping therapy (Hijama) on the hematological and the biochemical parameters in the healthy Arabian horses for the first time. Materials and Methods: In this study, seven clinically healthy Arabian horses were randomly selected. Four points on the animal body were selected to perform the cupping therapy. Two points were selected at the back just behind the scapula on the left and right sides; another two points were located in the rump. Cups with 4 oz (125 ml) size with narrow mouths were used. A manual pump (sucking cups) was used to create the negative pressure within the cups during cupping. Arterial and venous blood parameters and serum cortisol concentration were measured before cupping and 3 days and 2, 4, and 8 weeks after cupping. Results: No significant differences were estimated in most hematological and biochemical parameters after cupping. A significant decrease in the concentration of serum cortisol was observed in 3 and 14 days after cupping. Conclusions: Cupping induced minor changes on the hematological and biochemical parameters in Arabian horses. This is the first trial on the effects of wet cupping therapy on the different parameters in Arabian horses, which would be useful for further investigations on the role of complementary therapies in horses. Our further studies will include different disease models.
Stegmaier, Petra; Drendel, Vanessa; Mo, Xiaokui; Ling, Stella; Fabian, Denise; Manring, Isabel; Jilg, Cordula A.; Schultze-Seemann, Wolfgang; McNulty, Maureen; Zynger, Debra L.; Martin, Douglas; White, Julia; Werner, Martin; Grosu, Anca L.; Chakravarti, Arnab
2015-01-01
Purpose To develop a microRNA (miRNA)-based predictive model for prostate cancer patients of 1) time to biochemical recurrence after radical prostatectomy and 2) biochemical recurrence after salvage radiation therapy following documented biochemical disease progression post-radical prostatectomy. Methods Forty three patients who had undergone salvage radiation therapy following biochemical failure after radical prostatectomy with greater than 4 years of follow-up data were identified. Formalin-fixed, paraffin-embedded tissue blocks were collected for all patients and total RNA was isolated from 1mm cores enriched for tumor (>70%). Eight hundred miRNAs were analyzed simultaneously using the nCounter human miRNA v2 assay (NanoString Technologies; Seattle, WA). Univariate and multivariate Cox proportion hazards regression models as well as receiver operating characteristics were used to identify statistically significant miRNAs that were predictive of biochemical recurrence. Results Eighty eight miRNAs were identified to be significantly (p<0.05) associated with biochemical failure post-prostatectomy by multivariate analysis and clustered into two groups that correlated with early (≤ 36 months) versus late recurrence (>36 months). Nine miRNAs were identified to be significantly (p<0.05) associated by multivariate analysis with biochemical failure after salvage radiation therapy. A new predictive model for biochemical recurrence after salvage radiation therapy was developed; this model consisted of miR-4516 and miR-601 together with, Gleason score, and lymph node status. The area under the ROC curve (AUC) was improved to 0.83 compared to that of 0.66 for Gleason score and lymph node status alone. Conclusion miRNA signatures can distinguish patients who fail soon after radical prostatectomy versus late failures, giving insight into which patients may need adjuvant therapy. Notably, two novel miRNAs (miR-4516 and miR-601) were identified that significantly improve prediction of biochemical failure post-salvage radiation therapy compared to clinico-histopathological factors, supporting the use of miRNAs within clinically used predictive models. Both findings warrant further validation studies. PMID:25760964
Parekh, S; Bodicoat, D H; Brady, E; Webb, D; Mani, H; Mostafa, S; Levy, M J; Khunti, K; Davies, M J
2014-06-01
People who experience biochemical hypoglycaemia during an oral glucose tolerance test (OGTT) may be insulin resistant, but this has not been investigated robustly, therefore we examined this in a population-based multi-ethnic UK study. Cross-sectional data from 6478 diabetes-free participants (849 with fasting insulin data available) who had an OGTT in the ADDITION-Leicester screening study (2005-2009) were analysed. People with biochemical hypoglycaemia (2-h glucose <3.3mmol/l) were compared with people with normal glucose tolerance (NGT) or impaired glucose regulation (IGR) using regression methods. 359 participants (5.5%) had biochemical hypoglycaemia, 1079 (16.7%) IGR and 5040 (77.8%) NGT. Biochemical hypoglycaemia was associated with younger age (P<0.01), white European ethnicity (P<0.001), higher HDL cholesterol (P<0.01), higher insulin sensitivity (P<0.05), and lower body mass index (P<0.001), blood pressure (P<0.01), fasting glucose (P<0.001), HbA1C (P<0.01), and triglycerides (P<0.01) compared with NGT and IGR separately in both unadjusted and adjusted (age, sex, ethnicity, body mass index, smoking status) models. Biochemical hypoglycaemia during an OGTT in the absence of diabetes or IGR was not associated with insulin resistance, but instead appeared to be associated with more favourable glycaemic risk profiles than IGR and NGT. Thus, clinicians may not need to intervene due to biochemical hypoglycaemia on a 2-h OGTT. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
[Biochemical changes in apoptosis and methods for their determination (review)].
Sedláková, A; Kohút, A; Kalina, I
1999-08-01
Apoptosis or programmed cell death is a physiological process which occurs at different biological states as well as at disease process. Morphologically it is characterized by the chromatine condensation and other changes with preserved integrity of plasmatic membrane. The major and most frequently studied biochemical characteristic of apoptosis is a DNA fragmentation. In our paper attention is directed to the early biochemical changes in cell membranes, i.g., the externalization of phosphatidylserine, hydrolysis of sphingomyeline on the ceramide and activation of phospholipases especially phospholipase A2. In one part we described the changes of cysteine proteases (caspases), which play a key role in the execution of apoptosis. These biochemical changes are associated with ceramide signalization of apoptosis. Briefly are presented also some dates about apoptosis induction with reactive oxygen radicals and the role of the arachidonic acid metabolites in this process. We consider the investigation and determination of these changes as important parameters of apoptosis at some diseases, e.g., cancer or degenerative diseases, and of their treatment.
Simulation methods with extended stability for stiff biochemical Kinetics.
Rué, Pau; Villà-Freixa, Jordi; Burrage, Kevin
2010-08-11
With increasing computer power, simulating the dynamics of complex systems in chemistry and biology is becoming increasingly routine. The modelling of individual reactions in (bio)chemical systems involves a large number of random events that can be simulated by the stochastic simulation algorithm (SSA). The key quantity is the step size, or waiting time, tau, whose value inversely depends on the size of the propensities of the different channel reactions and which needs to be re-evaluated after every firing event. Such a discrete event simulation may be extremely expensive, in particular for stiff systems where tau can be very short due to the fast kinetics of some of the channel reactions. Several alternative methods have been put forward to increase the integration step size. The so-called tau-leap approach takes a larger step size by allowing all the reactions to fire, from a Poisson or Binomial distribution, within that step. Although the expected value for the different species in the reactive system is maintained with respect to more precise methods, the variance at steady state can suffer from large errors as tau grows. In this paper we extend Poisson tau-leap methods to a general class of Runge-Kutta (RK) tau-leap methods. We show that with the proper selection of the coefficients, the variance of the extended tau-leap can be well-behaved, leading to significantly larger step sizes. The benefit of adapting the extended method to the use of RK frameworks is clear in terms of speed of calculation, as the number of evaluations of the Poisson distribution is still one set per time step, as in the original tau-leap method. The approach paves the way to explore new multiscale methods to simulate (bio)chemical systems.
Zohdi, Vladislava; Whelan, Donna R; Wood, Bayden R; Pearson, James T; Bambery, Keith R; Black, M Jane
2015-01-01
Fourier Transform Infrared (FTIR) micro-spectroscopy is an emerging technique for the biochemical analysis of tissues and cellular materials. It provides objective information on the holistic biochemistry of a cell or tissue sample and has been applied in many areas of medical research. However, it has become apparent that how the tissue is handled prior to FTIR micro-spectroscopic imaging requires special consideration, particularly with regards to methods for preservation of the samples. We have performed FTIR micro-spectroscopy on rodent heart and liver tissue sections (two spectroscopically very different biological tissues) that were prepared by desiccation drying, ethanol substitution and formalin fixation and have compared the resulting spectra with that of fully hydrated freshly excised tissues. We have systematically examined the spectra for any biochemical changes to the native state of the tissue caused by the three methods of preparation and have detected changes in infrared (IR) absorption band intensities and peak positions. In particular, the position and profile of the amide I, key in assigning protein secondary structure, changes depending on preparation method and the lipid absorptions lose intensity drastically when these tissues are hydrated with ethanol. Indeed, we demonstrate that preserving samples through desiccation drying, ethanol substitution or formalin fixation significantly alters the biochemical information detected using spectroscopic methods when compared to spectra of fresh hydrated tissue. It is therefore imperative to consider tissue preparative effects when preparing, measuring, and analyzing samples using FTIR spectroscopy.
Comparison of avian biochemical test results with Abaxis VetScan and Hitachi 911 analyzers.
Greenacre, Cheryl B; Flatland, Bente; Souza, Marcy J; Fry, Michael M
2008-12-01
To compare results of clinical biochemical analysis using an Abaxis VetScan bench-top analyzer with reagents specifically marketed for avian use and a Hitachi 911 analyzer, plasma (both methods) and whole blood (VetScan method) samples from 20 clinically healthy Hispaniolan Amazon parrots (Amazona ventralis) were analyzed. Correlation between methods was very high (r = 0.9-1.0) for aspartate aminotransferase (AST), calcium, glucose, and uric acid; high (r = 0.7-0.89) for creatine kinase (CK), phosphorus, potassium, and total protein; moderate (r = 0.5-0.69) for globulin; and low (r = 0.3-0.49) for albumin and sodium. VetScan analyzer results for globulin, sodium, and uric acid had a constant negative bias (values below those from the Hitachi method). Based on difference plot analysis, results for AST, calcium, CK, and glucose are comparable. Because 16 of 20 values fell below the lower detection limit of the VetScan analyzer, bile acid data were excluded from analysis. By using a relatively small sample size (0.1 ml whole blood or plasma), the VetScan analyzer offers rapid in-house results, compact size, and ease of operation. For 4 of the most clinically relevant biochemical analytes used in avian medicine (AST, calcium, CK, glucose), it offers reliable values. For an additional 4 analytes (phosphorous, potassium, total protein, uric acid), establishing analyzer-specific reference intervals is recommended. Neither the VetScan nor the Hitachi method is recommended to assess albumin and globulin concentrations.
X-ray crystallography over the past decade for novel drug discovery - where are we heading next?
Zheng, Heping; Handing, Katarzyna B; Zimmerman, Matthew D; Shabalin, Ivan G; Almo, Steven C; Minor, Wladek
2015-01-01
Macromolecular X-ray crystallography has been the primary methodology for determining the three-dimensional structures of proteins, nucleic acids and viruses. Structural information has paved the way for structure-guided drug discovery and laid the foundations for structural bioinformatics. However, X-ray crystallography still has a few fundamental limitations, some of which may be overcome and complemented using emerging methods and technologies in other areas of structural biology. This review describes how structural knowledge gained from X-ray crystallography has been used to advance other biophysical methods for structure determination (and vice versa). This article also covers current practices for integrating data generated by other biochemical and biophysical methods with those obtained from X-ray crystallography. Finally, the authors articulate their vision about how a combination of structural and biochemical/biophysical methods may improve our understanding of biological processes and interactions. X-ray crystallography has been, and will continue to serve as, the central source of experimental structural biology data used in the discovery of new drugs. However, other structural biology techniques are useful not only to overcome the major limitation of X-ray crystallography, but also to provide complementary structural data that is useful in drug discovery. The use of recent advancements in biochemical, spectroscopy and bioinformatics methods may revolutionize drug discovery, albeit only when these data are combined and analyzed with effective data management systems. Accurate and complete data management is crucial for developing experimental procedures that are robust and reproducible.
Biochemical and nutritional components of selected honey samples.
Chua, Lee Suan; Adnan, Nur Ardawati
2014-01-01
The purpose of this study was to investigate the relationship of biochemical (enzymes) and nutritional components in the selected honey samples from Malaysia. The relationship is important to estimate the quality of honey based on the concentration of these nutritious components. Such a study is limited for honey samples from tropical countries with heavy rainfall throughout the year. A number of six honey samples that commonly consumed by local people were collected for the study. Both the biochemical and nutritional components were analysed by using standard methods from Association of Official Analytical Chemists (AOAC). Individual monosaccharides, disaccharides and 17 amino acids in honey were determined by using liquid chromatographic method. The results showed that the peroxide activity was positively correlated with moisture content (r = 0.8264), but negatively correlated with carbohydrate content (r = 0.7755) in honey. The chromatographic sugar and free amino acid profiles showed that the honey samples could be clustered based on the type and maturity of honey. Proline explained for 64.9% of the total variance in principle component analysis (PCA). The correlation between honey components and honey quality has been established for the selected honey samples based on their biochemical and nutritional concentrations. PCA results revealed that the ratio of sucrose to maltose could be used to measure honey maturity, whereas proline was the marker compound used to distinguish honey either as floral or honeydew.
Lammert, Craig; Juran, Brian D.; Schlicht, Erik; Chan, Landon L.; Atkinson, Elizabeth J.; de Andrade, Mariza; Lazaridis, Konstantinos N.
2014-01-01
Background Biochemical response to Ursodeoxycholic Acid among patients with Primary Biliary Cirrhosis remains variable and there is no agreement of an ideal model. Novel assessment of response coupled to histologic progression was recently defined by the Toronto criteria. We retrospectively assessed transplant-free survival and clinical outcomes associated with Ursodeoxycholic Acid response to evaluate the Toronto criteria using a large North American cohort of PBC patients. Methods 398 PBC patients from the Mayo Clinic PBC Genetic Epidemiology (MCPGE) Registry were assessed for Ursodeoxycholic Acid treatment and biochemical response per the Toronto criteria. Responders were defined by reduction in alkaline phosphatase to less than or equal to 1.67 times the upper normal limit by 2 years of treatment, whereas non-responders had alkaline phosphatase values greater than 1.67 times the upper normal limit. Probability of survival was estimated using the Kaplan-Meier method. Results 302 (76%) patients were responders and 96 (24%) were non-responders. Significantly more non-responders developed adverse events related to chronic liver disease compared to responders (Hazard Ratio (HR): 2.77, P = 0.001). Biochemical responders and early-stage disease at treatment start was associated with improved overall transplant-free survival compared to non-responders (HR: 1.9) and patients with late stage disease (HR: 2.7) after age and sex adjustment. Conclusions The Toronto criteria are capable of identifying Ursodeoxycholic Acid-treated Primary Biliary Cirrhosis patients at risk of poor transplant-free survival and adverse clinical outcomes. Our data reveal that despite advanced disease at diagnosis, biochemical response per the Toronto criteria associates with improved overall transplant-free survival. PMID:24317935
Voronkova, Anna V; Smaglyuk, Lyubov V
2018-01-01
Introduction: Many research studies involving orthodontic patients focus on changes in levels of oral microbiocenosis after bracket placement. Based upon this the objective of the current study was to determine the effect of the developed mucosal gel with probiotics on the biochemical parameters of the oral fluid of patients during the orthodontic treatment with a bracket system. The aim: Aim of our study is to determine the effect of the developed mucosal gel with probiotics on the biochemical parameters of the oral fluid of patients during the orthodontic treatment with a bracket system. Materials and methods: 45 patients at the age of 18-24, with 15 people in each group (control, main and comparison group) were examined. The main group was presented by patients who, in order to prevent dysbiosis of the oral cavity during orthodontic treatment, were prescribed local use of the developed mucosal gel with probiotic. The statistical processing of the results of the study was carried out using methods of variation statistics using the EXCEL program (the standard package of Microsoft Office). Results: According to the results of biochemical studies, it was found that the use of orthodontic treatment of mucosal gel with probiotic in patients with crowded teeth contributes to the strengthening of antioxidant protection, an increase in nonspecific resistance, decrease in inflammation and normalization of microbiocenosis of the oral cavity. Conclusion: These studies indicated that the use of the developed mucosal gel with probiotic in patients with maxillofacial anomalies from the first day after fixation, as indicated by the level of biochemical markers of inflammation.
Timmers, Henri J. L. M.; Pacak, Karel; Huynh, Thanh T.; Abu-Asab, Mones; Tsokos, Maria; Merino, Maria J.; Baysal, Bora E.; Adams, Karen T.; Eisenhofer, Graeme
2008-01-01
Context: Patients with adrenal and extra-adrenal abdominal paraganglioma (PGL) almost invariably have increased plasma and urine concentrations of metanephrines, the O-methylated metabolites of catecholamines. We report four cases of biochemically silent abdominal PGL, in which metanephrines were normal despite extensive disease. Objective: Our objective was to identify the mechanism underlying the lack of catecholamine hypersecretion and metabolism to metanephrines in biochemically silent PGL. Design: This is a descriptive study. Setting: The study was performed at a referral center. Patients: One index case and three additional patients with large abdominal PGL and metastases but with the lack of evidence of catecholamine production, six patients with metastatic catecholamine-producing PGL and a mutation of the succinate dehydrogenase subunit B (SDHB) gene, and 136 random patients with catecholamine-producing PGL were included in the study. Main Outcome Measures: Plasma, urine, and tumor tissue concentrations of catecholamines and metabolites were calculated with electron microscopy and tyrosine hydroxylase immunohistochemistry. Results: All four patients with biochemically silent PGL had an underlying SDHB mutation. In the index case, the tumor tissue concentration of catecholamines (1.8 nmol/g) was less than 0.01% that of the median (20,410 nmol/g) for the 136 patients with catecholamine-producing tumors. Electron microscopy showed the presence of normal secretory granules in all four biochemically silent PGLs. Tyrosine hydroxylase immunoreactivity was negligible in the four biochemically silent PGLs but abundant in catecholamine-producing PGLs. Conclusions: Patients with SDHB mutations may present with biochemically silent abdominal PGLs due to defective catecholamine synthesis resulting from the absence of tyrosine hydroxylase. Screening for tumors in patients with SDHB mutations should not be limited to biochemical tests of catecholamine excess. PMID:18840642
Adeli, Khosrow; Higgins, Victoria; Nieuwesteeg, Michelle; Raizman, Joshua E; Chen, Yunqi; Wong, Suzy L; Blais, David
2015-08-01
Biological covariates such as age and sex can markedly influence biochemical marker reference values, but no comprehensive study has examined such changes across pediatric, adult, and geriatric ages. The Canadian Health Measures Survey (CHMS) collected comprehensive nationwide health information and blood samples from children and adults in the household population and, in collaboration with the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER), examined biological changes in biochemical markers from pediatric to geriatric age, establishing a comprehensive reference interval database for routine disease biomarkers. The CHMS collected health information, physical measurements, and biosamples (blood and urine) from approximately 12 000 Canadians aged 3-79 years and measured 24 biochemical markers with the Ortho Vitros 5600 FS analyzer or a manual microplate. By use of CLSI C28-A3 guidelines, we determined age- and sex-specific reference intervals, including corresponding 90% CIs, on the basis of specific exclusion criteria. Biochemical marker reference values exhibited dynamic changes from pediatric to geriatric age. Most biochemical markers required some combination of age and/or sex partitioning. Two or more age partitions were required for all analytes except bicarbonate, which remained constant throughout life. Additional sex partitioning was required for most biomarkers, except bicarbonate, total cholesterol, total protein, urine iodine, and potassium. Understanding the fluctuations in biochemical markers over a wide age range provides important insight into biological processes and facilitates clinical application of biochemical markers to monitor manifestation of various disease states. The CHMS-CALIPER collaboration addresses this important evidence gap and allows the establishment of robust pediatric and adult reference intervals. © 2015 American Association for Clinical Chemistry.
Thompson, Scott M; Vella, Adrian; Service, F John; Grant, Clive S; Thompson, Geoffrey B; Andrews, James C
2015-07-01
To determine the impact of variant pancreatic arterial anatomy and overlap in regional perfusion on the interpretation of selective arterial calcium stimulation (SACST) with hepatic venous sampling for preoperative localization of occult insulinoma. An institutional review board-approved retrospective review was undertaken of 42 patients with surgically confirmed, occult insulinoma who underwent SACST from January 1996 to March 2014. Location of the insulinoma was predicted initially based on the biochemical results of SACST alone according to Doppman's criteria. Pancreatic arteriograms were reviewed blinded to the biochemical results and the regional perfusion of each artery assessed. The anatomic and perfusion data were combined with the biochemical results to make a second prediction and compared with the surgical findings. The biochemical results were positive in 1, 2, and 3 arterial distributions in 73.8%, 21.4%, and 4.8% of patients, respectively. The celiac trunk and superior mesenteric artery (SMA) anatomy were aberrant in 38.1% and 35.7% of patients, respectively. Clinically significant variations included dorsal pancreatic artery replaced to SMA (21.4%) and celiac stenosis (4.8%). Significant variation and overlap in regional pancreatic perfusion was observed, particularly for the SMA. Sensitivity for insulinoma localization was 54.8% (diagnostic arteriography), 73.8% (biochemical data), 88.1% (biochemical, anatomic, perfusion data), and 92.8% (arteriographic, biochemical, anatomic, perfusion data). Careful review of the pancreatic arterial anatomy and regional perfusion is critical for correct interpretation of the biochemical results of SACST and improves the sensitivity of localization for occult insulinoma, particularly in the presence of pancreatic arterial variants or overlap in regional perfusion. Copyright © 2015 Elsevier Inc. All rights reserved.
Microneedle arrays for biosensing and drug delivery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Joseph; Windmiller, Joshua Ray; Narayan, Roger
Methods, structures, and systems are disclosed for biosensing and drug delivery techniques. In one aspect, a^ device for detecting an analyte and/or releasing a biochemical into a biological fluid can include an array of hollowed needles, in which each needle includes a protruded needle structure including an exterior wall forming a hollow interior and an opening at a terminal end of the protruded needle structure that exposes the hollow interior, and a probe inside the exterior wall to interact with one or more chemical or biological substances that come in contact with the probe via the opening to produce amore » probe sensing signal, and an array of wires that are coupled to probes of the array of hollowed needles, respectively, each wire being electrically conductive to transmit the probe sensing signal produced by a respective probe.« less
Microneedle arrays for biosensing and drug delivery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Joseph; Windmiller, Joshua Ray; Narayan, Roger
Methods, structures, and systems are disclosed for biosensing and drug delivery techniques. In one aspect, a device for detecting an analyte and/or releasing a biochemical into a biological fluid can include an array of hollowed needles, in which each needle includes a protruded needle structure including an exterior wall forming a hollow interior and an opening at a terminal end of the protruded needle structure that exposes the hollow interior, and a probe inside the exterior wall to interact with one or more chemical or biological substances that come in contact with the probe via the opening to produce amore » probe sensing signal, and an array of wires that are coupled to probes of the array of hollowed needles, respectively, each wire being electrically conductive to transmit the probe sensing signal produced by a respective probe.« less
NASA Technical Reports Server (NTRS)
Ustin, Susan L.; Sanderson, Eric W.; Grossman, Yaffa; Hart, Quinn J.
1993-01-01
Advances in imaging spectroscopy have indicated that remotely sensed reflectance measurements of the plant canopy may be used to identify and qualify some classes of canopy biochemicals; however, the manner in which differences in biochemical compositions translate into differences is not well understood. Most frequently, multiple linear regression routines have been used to correlate narrow band reflectance values with measured biochemical concentrations. Although some success has been achieved with such methods for given data sets, the bands selected by multiple regression are not consistent between data sets, nor is it always clear what physical or biological basis underlies the correlation. To examine the relationship between biochemical concentration and leaf reflectance signal we chose to focus on the visible spectrum where the primary biochemical absorbances are due to photosynthetic pigments. Pigments provide a range of absorbance features, occur over a range of concentrations in natural samples, and are ecophysiologically important. Concentrations of chlorophyll, for example, have been strongly correlated to foliar nitrogen levels within a species and to photosynthetic capacity across many species. In addition pigments effectively absorb most of the photosynthetically active radiation between 400-700 nm, a spectral region for which silicon detectors have good signal/noise characteristics. Our strategy has been to sample a variety of naturally occurring species to measure leaf reflectance and pigment compositions. We hope to extend our understanding of pigment reflectance effects to interpret small overlapping absorbances of other biochemicals in the infrared region. For this reason, selected samples were also tested to determine total nitrogen, crude protein, cellulose, and lignin levels. Leaf reflectance spectra measured with AVIRIS bandwidths and wavelengths were compared between species and within species and for differences between seasons, for changes in the the shape of the spectra. We attempt to statistically correlate these shape changes with differences in pigment compositions. In parallel with our comparisons of pigment composition and leaf reflectance, we have modified the PROSPECT leaf reflectance model to test the contributions of pigments or pigment group concentrations. PROSPECT considers a leaf as a multi-layer dielectric plane with an uneven surface. Jacquemoud adapted the basic analysis of Allen for surface effects, a leaf thickness factor, and the absorption of water and chlorophyll (actually all pigments) and the plant matrix. Our modifications to PROSPECT in the forward direction include breaking out the pigment concentration parameter into separate components for chlorophyll a and b and a number of xanthophylls and carotenes, and introducing a shift and convolution function to model the spread and shift from their in vitro measurements to their in vivo state. Further, we have considered how the matrix elements (i.e., all biochemicals and structural effects not modeled explicity) vary with species.
Univariate and multivariate methods for chemical mapping of cervical cancer cells
NASA Astrophysics Data System (ADS)
Duraipandian, Shiyamala; Zheng, Wei; Huang, Zhiwei
2012-01-01
Visualization of cells and subcellular organelles are currently carried out using available microscopy methods such as cryoelectron microscopy, and fluorescence microscopy. These methods require external labeling using fluorescent dyes and extensive sample preparations to access the subcellular structures. However, Raman micro-spectroscopy provides a non-invasive, label-free method for imaging the cells with chemical specificity at sub-micrometer spatial resolutions. The scope of this paper is to image the biochemical/molecular distributions in cells associated with cancerous changes. Raman map data sets were acquired from the human cervical carcinoma cell lines (HeLa) after fixation under 785 nm excitation wavelength. The individual spectrum was recorded by raster-scanning the laser beam over the sample with 1μm step size and 10s exposure time. Images revealing nucleic acids, lipids and proteins (phenylalanine, amide I) were reconstructed using univariate methods. In near future, the small pixel to pixel variations will also be imaged using different multivariate methods (PCA, clustering (HCA, K-means, FCM)) to determine the main cellular constitutions. The hyper-spectral image of cell was reconstructed utilizing the spectral contrast at different pixels of the cell (due to the variation in the biochemical distribution) without using fluorescent dyes. Normal cervical squamous cells will also be imaged in order to differentiate normal and cancer cells of cervix using the biochemical changes in different grades of cancer. Based on the information obtained from the pseudo-color maps, constructed from the hyper-spectral cubes, the primary cellular constituents of normal and cervical cancer cells were identified.
Freeman, D A; Cymbaluk, N F; Schott, H C; Hinchcliff, K; McDonnell, S M; Kyle, B
1999-11-01
To compare health, hydration status, and management of stabled pregnant mares provided drinking water continuously or via 1 of 3 intermittent delivery systems. 22 Quarter Horse (QH) or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 1); 24 QH or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 2). Stabled horses were provided water continuously or via 1 of 3 intermittent water delivery systems in 2 study periods during a 2-year period. Body temperature, attitude, appetite, water intake, and urine output were recorded daily. Hygiene of each horse and the stable were assessed weekly. Clinical and biochemical measures of hydration were determined 3 times during each study. Clinical measures of hydration included skin turgor, gum moisture, capillary refill time, and fecal consistency. Biochemical measures of hydration included PCV, plasma total protein concentration, serum osmolality, plasma vasopressin concentration, urine specific gravity, and urine osmolality. All horses remained healthy. Stable hygiene was worse when horses had continuous access to water. Clinical and biochemical measures of hydration did not differ among water delivery systems. Various continuous and intermittent water delivery systems provided adequate amounts of water to stabled horses to maintain health and hydration status. Providing intermittent access to water may be preferable on the basis of stable hygiene.
Sands, Dorota; Mielus, Monika; Umławska, Wioleta; Lipowicz, Anna; Oralewska, Beata; Walkowiak, Jarosław
2015-09-01
The aim of the study was to evaluate factors related to bone formation and resorption in Polish children and adolescents with cystic fibrosis and to examine the effect of nutritional status, biochemical parameters and clinical status on bone mineral density. The study group consisted of 100 children and adolescents with cystic fibrosis with a mean age 13.4 years old. Anthropometric measurements, included body height, body mass and body mass index (BMI); bone mineral densitometry and biochemical testing were performed. Bone mineral density was measured using a dual-energy X-ray absorption densitometer. Biochemical tests included serum calcium, phosphorus, parathyroid hormone and vitamin D concentrations, as well as 24-h urine calcium and phosphorus excretion. Pulmonary function was evaluated using FEV1%, and clinical status was estimated using the Shwachman-Kulczycki score. Standardized body height, body mass and BMI were significantly lower than in the reference population. Mean serum vitamin D concentration was decreased. Pulmonary disease was generally mild, with a mean FEV1% of 81%. Multivariate linear regression revealed that the only factors that had a significant effect on bone marrow density were BMI and FEV1%. There were no significant correlations between bone mineral density and the results of any of the biochemical tests performed. Nutritional status and bone mineral density were significantly decreased in children and adolescents with cystic fibrosis. In spite of abnormalities in biochemical testing, the factors that were found to have the strongest effect on bone mineral density were standardized BMI and clinical status. Copyright © 2015. Published by Elsevier Urban & Partner Sp. z o.o.
Rapid preparation of a noncultured skin cell suspension that promotes wound healing.
Yoon, Cheonjae; Lee, Jungsuk; Jeong, Hyosun; Lee, Sungjun; Sohn, Taesik; Chung, Sungphil
2017-06-01
Autologous skin cell suspensions have been used for wound healing in patients with burns and against normal pigmentation in vitiligo. To separate cells and the extracellular matrix from skin tissue, most researchers use enzymatic digestion. Therefore, this process is difficult to perform during a routine surgical procedure. We aimed to prepare a suspension of noncultured autologous skin cells (NCSCs) using a tissue homogenizer as a new method instead of harsh biochemical reagents. The potential clinical applicability of NCSCs was analyzed using a nude-rat model of burn healing. After optimization of the homogenizer settings, cell viability ranged from 52 to 89%. Scanning electron microscopy showed evidence of keratinocyte-like cell morphology, and several growth factors, including epidermal growth factor and basic fibroblast growth factor, were present in the NCSCs. The rat model revealed that NCSCs accelerated skin regeneration. NCSCs could be generated using a tissue homogenizer for enhancement of wound healing in vivo. In the NCSC group of wounds, on day 7 of epithelialization, granulation was observed, whereas on day 14, there was a significant increase in skin adnexa regeneration as compared to the control group (PBS treatment; p < 0.05). This study suggests that the proposed process is rapid and does not require the use of biochemical agents. Thus, we recommend a combination of surgical treatment with the new therapy for a burn as an effective method.
Alcohols as alkylating agents in heteroarene C–H functionalization
Jin, Jian; MacMillan, David W. C.
2015-01-01
Redox processes and radical intermediates are found in many biochemical processes, including deoxyribonucleotide synthesis and oxidative DNA damage1. One of the core principles that underlies DNA biosynthesis is the radical-mediated elimnation of H2O to deoxygenate ribonucleotides, an example of ‘spin-center shift’ (SCS)2, during which an alcohol C–O bond is cleaved, resulting in a carbon-centered radical intermediate. While SCS is a well-understood biochemical process, it is underutilized by the synthetic organic chemistry community. We wondered whether it would be possible to take advantage of this naturally occurring process to accomplish mild, non-traditional alkylations using alcohols as radical precursors. Considering traditional radical-based alkylation methods require the use of stoichiometric oxidants, elevated temperatures, or peroxides3–7, the development of a mild protocol using simple and abundant alkylating agents would have significant utility in the synthesis of diversely functionalized pharmacophores. In this manuscript, we describe the successful execution of this idea via the development of a dual catalytic alkylation of heteroarenes using alcohols as mild alkylating reagents. This method represents the first broadly applicable use of unactivated alcohols as latent alkylating reagents, achieved via the successful merger of photoredox and hydrogen atom transfer (HAT) catalysis. The utility of this multi-catalytic protocol has been demonstrated through the late-stage functionalization of the medicinal agents, fasudil and milrinone. PMID:26308895
Chen, Jun-Feng; Liao, Yu-Feng; Ma, Jian-Bo; Mao, Qi-Feng; Jia, Guang-Cheng; Dong, Xue-Jun
2017-07-01
To investigate the value of circulating miR-152 in the early prediction of postoperative biochemical recurrence of prostate cancer. Sixty-six cases of prostate cancer were included in this study, 35 with and 31 without biochemical recurrence within two years postoperatively, and another 31 healthy individuals were enrolled as normal controls. The relative expression levels of circulating miR-152 in the serum of the subjects were detected by qRT-PCR, its value in the early diagnosis of postoperative biochemical recurrence of prostate cancer was assessed by ROC curve analysis, and the correlation of its expression level with the clinicopathological parameters of the patients were analyzed. The expression of circulating miR-152 was significantly lower in the serum of the prostate cancer patients than in the normal controls (t = -5.212, P = 0.001), and so was it in the patients with than in those without postoperative biochemical recurrence (t = -5.727, P = 0.001). The ROC curve for the value of miR-152 in the early prediction of postoperative biochemical recurrence of prostate cancer showed the area under the curve (AUC) to be 0.906 (95% CI: 0.809-0.964), with a sensitivity of 91.4% and a specificity of 80.6%. The expression level of miR-152 was correlated with the Gleason score, clinical stage of prostate cancer, biochemical recurrence, and bone metastasis (P <0.05), decreasing with increased Gleason scores and elevated clinical stage of the malignancy. No correlation, however, was found between the miR-152 expression and the patients' age or preoperative PSA level (P >0.05). The expression level of circulating miR-152 is significantly reduced in prostate cancer patients with biochemical recurrence after prostatectomy and could be a biomarker in the early prediction of postoperative biochemical recurrence of the malignancy.
Unravelling the mysteries of sub-second biochemical processes using time-resolved mass spectrometry.
Lento, Cristina; Wilson, Derek J
2017-05-21
Many important chemical and biochemical phenomena proceed on sub-second time scales before entering equilibrium. In this mini-review, we explore the history and recent advancements of time-resolved mass spectrometry (TRMS) for the characterization of millisecond time-scale chemical reactions and biochemical processes. TRMS allows for the simultaneous tracking of multiple reactants, intermediates and products with no chromophoric species required, high sensitivity and temporal resolution. The method has most recently been used for the characterization of several short-lived reaction intermediates in rapid chemical reactions. Most of the reactions that occur in living organisms are accelerated by enzymes, with pre-steady state kinetics only attainable using time-resolved methods. TRMS has been increasingly used to monitor the conversion of substrates to products and the resulting changes to the enzyme during catalytic turnover. Early events in protein folding systems have also been elucidated, along with the characterization of dynamics and transient secondary structures in intrinsically disordered proteins. In this review, we will highlight representative examples where TRMS has been applied to study these phenomena.
Ture, M; Altinok, I; Capkin, E
2015-01-01
Biochemical test, pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR) were used to compare 42 strains of Lactococcus garvieae isolated from different regions of Turkey, Italy, France and Spain. Twenty biotypes of L. garvieae were formed based on 54 biochemical tests. ERIC-PCR of genomic DNA from different L. garvieae strains resulted in amplification of multiple fragments of DNA in sizes ranging between 200 and 5000 bp with various band intensities. After cutting DNA with ApaI restriction enzyme and running on the PFGE, 11–22 resolvable bands ranging from 2 to 194 kb were observed. Turkish isolates were grouped into two clusters, and only A58 (Italy) strain was connected with Turkish isolates. Similarities between Turkish, Spanish, Italian and French isolates were <50% except 216-6 Rize strain. In Turkey, first lactococcosis occurred in Mugla, and then, it has been spread all over the country. Based on ERIC-PCR, Spanish and Italian strains of L. garvieae were related to Mugla strains. Therefore, after comparing PFGE profiles, ERIC-PCR profiles and phenotypic characteristics of 42 strains of L. garvieae, there were no relationships found between these three typing methods. PFGE method was more discriminative than the other methods. © 2014 John Wiley & Sons Ltd.
Aligned and Electrospun Piezoelectric Polymer Fiber Assembly and Scaffold
NASA Technical Reports Server (NTRS)
Holloway, Nancy M. (Inventor); Scott-Carnell, Lisa A. (Inventor); Siochi, Emilie J. (Inventor); Leong, Kam W. (Inventor); Kulangara, Karina (Inventor)
2015-01-01
A scaffold assembly and related methods of manufacturing and/or using the scaffold for stem cell culture and tissue engineering applications are disclosed which at least partially mimic a native biological environment by providing biochemical, topographical, mechanical and electrical cues by using an electroactive material. The assembly includes at least one layer of substantially aligned, electrospun polymer fiber having an operative connection for individual voltage application. A method of cell tissue engineering and/or stem cell differentiation uses the assembly seeded with a sample of cells suspended in cell culture media, incubates and applies voltage to one or more layers, and thus produces cells and/or a tissue construct. In another aspect, the invention provides a method of manufacturing the assembly including the steps of providing a first pre-electroded substrate surface; electrospinning a first substantially aligned polymer fiber layer onto the first surface; providing a second pre-electroded substrate surface; electrospinning a second substantially aligned polymer fiber layer onto the second surface; and, retaining together the layered surfaces with a clamp and/or an adhesive compound.
Aligned and Electrospun Piezoelectric Polymer Fiber Assembly and Scaffold
NASA Technical Reports Server (NTRS)
Kulangara, Karina (Inventor); Scott Carnell, Lisa A. (Inventor); Holloway, Nancy M. (Inventor); Leong, Kam W. (Inventor); Siochi, Emilie J. (Inventor)
2017-01-01
A method of manufacturing and/or using a scaffold assembly for stem cell culture and tissue engineering applications is disclosed. The scaffold at least partially mimics a native biological environment by providing biochemical, topographical, mechanical and electrical cues by using an electroactive material. The assembly includes at least one layer of substantially aligned, electrospun polymer fiber having an operative connection for individual voltage application. A method of cell tissue engineering and/or stem cell differentiation that uses the assembly seeded with a sample of cells suspended in cell culture media, incubates and applies voltage to one or more layers, and thus produces cells and/or a tissue construct. In another aspect, the invention provides a method of manufacturing the assembly including the steps of providing a first pre-electroded substrate surface; electrospinning a first substantially aligned polymer fiber layer onto the first surface; providing a second pre-electroded substrate surface; electrospinning a second substantially aligned polymer fiber layer onto the second surface; and, retaining together the layered surfaces with a clamp and/or an adhesive compound.
Nwosu, Amara Callistus; Mayland, Catriona R; Mason, Stephen R; Khodabukus, Andrew F; Varro, Andrea; Ellershaw, John E
2013-09-01
Decisions surrounding the administration of clinically assisted hydration to patients dying of cancer can be challenging because of the limited understanding of hydration in advanced cancer and a lack of evidence to guide health care professionals. Bioelectrical impedance analysis (BIA) has been used to assess hydration in various patient groupings, but evidence for its use in advanced cancer is limited. To critically appraise existing methods of hydration status assessment in advanced cancer and review the potential for BIA to assess hydration in advanced cancer. Searches were carried out in four electronic databases. A hand search of selected peer-reviewed journals and conference abstracts also was conducted. Studies reporting (de)hydration assessment (physical examination, biochemical measures, symptom assessment, and BIA) in patients with advanced cancer were included. The results highlight how clinical examination and biochemical tests are standard methods of assessing hydration, but limitations exist with these methods in advanced cancer. Furthermore, there is disagreement over the evidence for some commonly associated symptoms with dehydration in cancer. Although there are limitations with using BIA alone to assess hydration in advanced cancer, analysis of BIA raw measurements through the method of bioelectrical impedance vector analysis may have a role in this population. The benefits and burdens of providing clinically assisted hydration to patients dying of cancer are unclear. Bioelectrical impedance vector analysis shows promise as a hydration assessment tool but requires further study in advanced cancer. Innovative methodologies for research are required to add to the evidence base and ultimately improve the care for the dying. Copyright © 2013 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.
Microorganism mediated liquid fuels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Troiano, Richard
Herein disclosed is a method for producing liquid hydrocarbon product, the method comprising disintegrating a hydrocarbon source; pretreating the disintegrated hydrocarbon source; solubilizing the disintegrated hydrocarbon source to form a slurry comprising a reactant molecule of the hydrocarbon source; admixing a biochemical liquor into the slurry, wherein the biochemical liquor comprises at least one conversion enzyme configured to facilitate bond selective photo-fragmentation of said reactant molecule of the hydrocarbon source, to form liquid hydrocarbons via enzyme assisted bond selective photo-fragmentation, wherein said conversion enzyme comprises reactive sites configured to restrict said reactant molecule such that photo-fragmentation favorably targets a preselectedmore » internal bond of said reactant molecule; separating the liquid hydrocarbons from the slurry, wherein contaminants remain in the slurry; and enriching the liquid hydrocarbons to form a liquid hydrocarbon product. Various aspects of such method/process are also discussed.« less
Simple biogas desulfurization by microaeration - Full scale experience.
Jeníček, P; Horejš, J; Pokorná-Krayzelová, L; Bindzar, J; Bartáček, J
2017-08-01
Hydrogen sulfide in biogas is common problem during anaerobic treatment of wastewater with high sulfate concentration (breweries, distilleries, etc.) and needs to be removed before biogas utilization. Physico-chemical desulfurization methods are energetically demanding and expensive compare to biochemical methods. Microaeration, i.e. dosing of small amount of air, is suitable and cost effective biochemical method of sulfide oxidation to elemental sulfur. It has been widely used in biogas plants, but its application in anaerobic reactors for wastewater treatment has been rarely studied or tested. The lack of full-scale experience with microaeration in wastewater treatment plants has been overcome by evaluating the results of seven microaerobic digesters in central Europe. The desulfurization efficiency has been more than 90% in most of the cases. Moreover, microaeration improved the degradability of COD and volatile suspended solids. Copyright © 2017 Elsevier Ltd. All rights reserved.
STEPS: efficient simulation of stochastic reaction-diffusion models in realistic morphologies.
Hepburn, Iain; Chen, Weiliang; Wils, Stefan; De Schutter, Erik
2012-05-10
Models of cellular molecular systems are built from components such as biochemical reactions (including interactions between ligands and membrane-bound proteins), conformational changes and active and passive transport. A discrete, stochastic description of the kinetics is often essential to capture the behavior of the system accurately. Where spatial effects play a prominent role the complex morphology of cells may have to be represented, along with aspects such as chemical localization and diffusion. This high level of detail makes efficiency a particularly important consideration for software that is designed to simulate such systems. We describe STEPS, a stochastic reaction-diffusion simulator developed with an emphasis on simulating biochemical signaling pathways accurately and efficiently. STEPS supports all the above-mentioned features, and well-validated support for SBML allows many existing biochemical models to be imported reliably. Complex boundaries can be represented accurately in externally generated 3D tetrahedral meshes imported by STEPS. The powerful Python interface facilitates model construction and simulation control. STEPS implements the composition and rejection method, a variation of the Gillespie SSA, supporting diffusion between tetrahedral elements within an efficient search and update engine. Additional support for well-mixed conditions and for deterministic model solution is implemented. Solver accuracy is confirmed with an original and extensive validation set consisting of isolated reaction, diffusion and reaction-diffusion systems. Accuracy imposes upper and lower limits on tetrahedron sizes, which are described in detail. By comparing to Smoldyn, we show how the voxel-based approach in STEPS is often faster than particle-based methods, with increasing advantage in larger systems, and by comparing to MesoRD we show the efficiency of the STEPS implementation. STEPS simulates models of cellular reaction-diffusion systems with complex boundaries with high accuracy and high performance in C/C++, controlled by a powerful and user-friendly Python interface. STEPS is free for use and is available at http://steps.sourceforge.net/
Mazhar, Amaan; Sharif, Seyed A.; Cuccia, J. David; Nelson, J. Stuart; Kelly, Kristen M.; Durkin, Anthony J.
2012-01-01
Background and Objective Objective methods to assess port wine stain (PWS) response to laser treatment have been the subject of various research efforts for several years. Herein, we present a pilot study using a newly developed, light emitting diode (LED) based spatial frequency domain imaging (SFDI) device to record quantitatively biochemical compositional changes in PWS after laser therapy. Study Design/Patients and Methods A SFDI system was used to image before, and after, five PWS treatment sessions [n = 4 subjects (one subject was imaged before and after two consecutive laser treatments)]. SFDI derived wide-field optical properties (absorption and scattering) and tissue chromophore concentrations including oxy-hemoglobin (ctO2Hb), deoxy-hemoglobin (ctHHb), total hemoglobin (ctTHb), and tissue oxygen saturation (stO2) are presented for skin imaged prior to and immediately after laser treatment. The SFDI derived images were analyzed by comparing the above measurements in PWS to those of normal skin and tracking changes immediately after laser exposure. Results Elevated oxy-hemoglobin (>20%) and tissue oxygen saturation (>5%) were measured in all PWS lesions and compared to values for normal skin prior to treatment. Laser treatment resulted in an increase in deoxy-hemoglobin (>100%), decrease in tissue oxygen saturation (>10%), and reduced scattering (>15%) in all PWS lesions. One subject was followed before and after two consecutive laser treatments and the overall improvement in PWS lesion blanching was quantitatively assessed by measuring a 45% decrease in dermal blood volume. Conclusion SFDI is a rapid non-contact wide-field optical technique that shows potential as an imaging device that can be used to quantify biochemical compositional changes in PWS after laser therapy. Future work will investigate the potential of SFDI to provide intra-operative guidance for laser therapy of PWS lesions on an individual patient basis. PMID:22911574
STEPS: efficient simulation of stochastic reaction–diffusion models in realistic morphologies
2012-01-01
Background Models of cellular molecular systems are built from components such as biochemical reactions (including interactions between ligands and membrane-bound proteins), conformational changes and active and passive transport. A discrete, stochastic description of the kinetics is often essential to capture the behavior of the system accurately. Where spatial effects play a prominent role the complex morphology of cells may have to be represented, along with aspects such as chemical localization and diffusion. This high level of detail makes efficiency a particularly important consideration for software that is designed to simulate such systems. Results We describe STEPS, a stochastic reaction–diffusion simulator developed with an emphasis on simulating biochemical signaling pathways accurately and efficiently. STEPS supports all the above-mentioned features, and well-validated support for SBML allows many existing biochemical models to be imported reliably. Complex boundaries can be represented accurately in externally generated 3D tetrahedral meshes imported by STEPS. The powerful Python interface facilitates model construction and simulation control. STEPS implements the composition and rejection method, a variation of the Gillespie SSA, supporting diffusion between tetrahedral elements within an efficient search and update engine. Additional support for well-mixed conditions and for deterministic model solution is implemented. Solver accuracy is confirmed with an original and extensive validation set consisting of isolated reaction, diffusion and reaction–diffusion systems. Accuracy imposes upper and lower limits on tetrahedron sizes, which are described in detail. By comparing to Smoldyn, we show how the voxel-based approach in STEPS is often faster than particle-based methods, with increasing advantage in larger systems, and by comparing to MesoRD we show the efficiency of the STEPS implementation. Conclusion STEPS simulates models of cellular reaction–diffusion systems with complex boundaries with high accuracy and high performance in C/C++, controlled by a powerful and user-friendly Python interface. STEPS is free for use and is available at http://steps.sourceforge.net/ PMID:22574658
2017-10-01
REPORT DATE: October 2017 TYPE OF REPORT: Annual PREPARED FOR: U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland 21702...AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland 21702-5012 11. SPONSOR...prostate cancer (PCa). Methods : We enrolled 15 men with biochemically recurrent PCa from May to Sep 2017, 63-79 year-old (mean±standard deviation (SD
Tisdall, P A; DeYoung, D R; Roberts, G D; Anhalt, J P
1982-01-01
Identification of routine mycobacterial isolates by gas-liquid chromatography profile analysis was performed on 335 strains received at the Mayo Clinic over a 10-month period. Comparison of identification by gas-liquid chromatography versus conventional biochemical profiles was made. The two methods agreed on the identification of 320 isolates, with gas-liquid chromatography profiling making eight errors and biochemical profiling making four errors. In three cases, discrepancies could not be resolved. PMID:6811612
Hybrid pathwise sensitivity methods for discrete stochastic models of chemical reaction systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wolf, Elizabeth Skubak, E-mail: ewolf@saintmarys.edu; Anderson, David F., E-mail: anderson@math.wisc.edu
2015-01-21
Stochastic models are often used to help understand the behavior of intracellular biochemical processes. The most common such models are continuous time Markov chains (CTMCs). Parametric sensitivities, which are derivatives of expectations of model output quantities with respect to model parameters, are useful in this setting for a variety of applications. In this paper, we introduce a class of hybrid pathwise differentiation methods for the numerical estimation of parametric sensitivities. The new hybrid methods combine elements from the three main classes of procedures for sensitivity estimation and have a number of desirable qualities. First, the new methods are unbiased formore » a broad class of problems. Second, the methods are applicable to nearly any physically relevant biochemical CTMC model. Third, and as we demonstrate on several numerical examples, the new methods are quite efficient, particularly if one wishes to estimate the full gradient of parametric sensitivities. The methods are rather intuitive and utilize the multilevel Monte Carlo philosophy of splitting an expectation into separate parts and handling each in an efficient manner.« less
NASA Astrophysics Data System (ADS)
Hug, William F.; Bhartia, Rohit; Taspin, Alexandre; Lane, Arthur; Conrad, Pamela; Sijapati, Kripa; Reid, Ray D.
2005-11-01
Laser induced native fluorescence (LINF) is the most sensitive method of detection of biological material including microorganisms, virus', and cellular residues. LINF is also a sensitive method of detection for many non-biological materials as well. The specificity with which these materials can be classified depends on the excitation wavelength and the number and location of observation wavelengths. Higher levels of specificity can be obtained using Raman spectroscopy but a much lower levels of sensitivity. Raman spectroscopy has traditionally been employed in the IR to avoid fluorescence. Fluorescence rarely occurs at wavelength below about 270nm. Therefore, when excitation occurs at a wavelength below 250nm, no fluorescence background occurs within the Raman fingerprint region for biological materials. When excitation occurs within electronic resonance bands of the biological target materials, Raman signal enhancement over one million typically occurs. Raman sensitivity within several hundred times fluorescence are possible in the deep UV where most biological materials have strong absorption. Since the Raman and fluorescence emissions occur at different wavelength, both spectra can be observed simultaneously, thereby providing a sensor with unique sensitivity and specificity capability. We will present data on our integrated, deep ultraviolet, LINF/Raman instruments that are being developed for several applications including life detection on Mars as well as biochemical warfare agents on Earth. We will demonstrate the ability to discriminate organic materials based on LINF alone. Together with UV resonance Raman, higher levels of specificity will be demonstrated. In addition, these instruments are being developed as on-line chemical sensors for industrial and municipal waste streams and product quality applications.
Basanta-Alario, María Luisa; Ferri, Jordi; Civera, Miguel; Martínez-Hervás, Sergio; Ascaso, Juan Francisco; Real, José Tomás
2016-02-01
Type 2 diabetes mellitus (T2DM) is a chronic, highly prevalent disease that increases with age. Because of this, and due to its chronic complications, T2DM causes high human, social, and financial costs. In addition, the elderly population with T2DM has a marked clinical heterogeneity. Therefore, our main objective was to analyze the relationship of age with the clinical and biological manifestations of the disease and the prevalence of chronic complications in patients with T2DM. A cross-sectional study of a large population with T2DM (n=405) randomly selected from a Diabetes Unit and 2 health care centers (60%). The clinical, anthropometric, and biochemical variables of the subjects were collected using standard methods to assess the effect of age on the clinical and biochemical phenotype of patients with T2DM. We have noted that patients with T2DM > 70 years old have a clinical and biochemical phenotype different from younger subjects (<60 years) including longer times since diabetes onset, higher diastolic blood pressure levels, and lower body mass index (BMI) values. As regards to biological variables, these patients have lower triglyceride levels, impaired kidney function, and lower HbA1c values. Prevalence of metabolic syndrome is lower in patients with T2DM > 70 years of age. Age was inversely related to parameters associated to metabolic syndrome (BMI, waist circumference, blood pressure, and triglyceride levels). We have defined the clinical and biochemical profile of patients with T2DM > 70 years attending health care centers. In addition, the prevalence of stroke, kidney disease, and distal symmetrical polyneuropathy is higher in patients with T2DM >70 years as compared to younger patients (<60 years). Copyright © 2015 SEEN. Published by Elsevier España, S.L.U. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Molina, Sarah; Department of Radiation Oncology, CHU/Université de Poitiers, Poitiers; Guerif, Stéphane
Purpose: Predictive factors for biochemical recurrence (BCR) in localized prostate cancer (PCa) after brachytherapy are insufficient to date. Cellular radiosensitivity depends on DNA double-strand breaks, mainly repaired by the nonhomologous end-joining (NHEJ) system. We analyzed whether the expression of NHEJ proteins can predict BCR in patients treated by brachytherapy for localized PCa. Methods and Materials: From 983 PCa cases treated by brachytherapy between March 2000 and March 2012, 167 patients with available biopsy material suitable for in situ analysis were included in the study. The median follow-up time was 47 months. Twenty-nine patients experienced BCR. All slides were reviewed to reassessmore » the Gleason score. Expression of the key NHEJ proteins DNA-PKcs, Ku70, and Ku80, and the proliferation marker Ki67, was studied by immunohistochemistry performed on tissue microarrays. Results: The Gleason scores after review (P=.06) tended to be associated with BCR when compared with the score initially reported (P=.74). Both the clinical stage (P=.02) and the pretreatment prostate-specific antigen level (P=.01) were associated with biochemical failure. Whereas the expression of Ku80 and Ki67 were not predictive of relapse, positive DNA-PKcs nuclear staining (P=.003) and higher Ku70 expression (P=.05) were associated with BCR. On multivariate analysis, among pretreatment variables, only DNA-PKcs (P=.03) and clinical stage (P=.02) remained predictive of recurrence. None of the patients without palpable PCa and negative DNA-PKcs expression experienced biochemical failure, compared with 32% of men with palpable and positive DNA-PKcs staining that recurred. Conclusions: Our results suggest that DNA-PKcs could be a predictive marker of BCR after brachytherapy, and this might be a useful tool for optimizing the choice of treatment in low-risk PCa patients.« less
An affinity-structure database of helix-turn-helix: DNA complexes with a universal coordinate system
DOE Office of Scientific and Technical Information (OSTI.GOV)
AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide
Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database inmore » which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. Lastly, this database will facilitate the analysis of protein-DNA interactions and the development of programmatic computational methods that capitalize on integration of structural and biochemical datasets. The database can be accessed at http://ProteinDNA.hms.harvard.edu.« less
An affinity-structure database of helix-turn-helix: DNA complexes with a universal coordinate system
AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide
2015-11-19
Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database inmore » which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. Lastly, this database will facilitate the analysis of protein-DNA interactions and the development of programmatic computational methods that capitalize on integration of structural and biochemical datasets. The database can be accessed at http://ProteinDNA.hms.harvard.edu.« less
BioCluster: tool for identification and clustering of Enterobacteriaceae based on biochemical data.
Abdullah, Ahmed; Sabbir Alam, S M; Sultana, Munawar; Hossain, M Anwar
2015-06-01
Presumptive identification of different Enterobacteriaceae species is routinely achieved based on biochemical properties. Traditional practice includes manual comparison of each biochemical property of the unknown sample with known reference samples and inference of its identity based on the maximum similarity pattern with the known samples. This process is labor-intensive, time-consuming, error-prone, and subjective. Therefore, automation of sorting and similarity in calculation would be advantageous. Here we present a MATLAB-based graphical user interface (GUI) tool named BioCluster. This tool was designed for automated clustering and identification of Enterobacteriaceae based on biochemical test results. In this tool, we used two types of algorithms, i.e., traditional hierarchical clustering (HC) and the Improved Hierarchical Clustering (IHC), a modified algorithm that was developed specifically for the clustering and identification of Enterobacteriaceae species. IHC takes into account the variability in result of 1-47 biochemical tests within this Enterobacteriaceae family. This tool also provides different options to optimize the clustering in a user-friendly way. Using computer-generated synthetic data and some real data, we have demonstrated that BioCluster has high accuracy in clustering and identifying enterobacterial species based on biochemical test data. This tool can be freely downloaded at http://microbialgen.du.ac.bd/biocluster/. Copyright © 2015 The Authors. Production and hosting by Elsevier Ltd.. All rights reserved.
Chemical and biochemical thermodynamics: Is it time for a reunification?
Iotti, Stefano; Raff, Lionel; Sabatini, Antonio
2017-02-01
The thermodynamics of chemical reactions in which all species are explicitly considered with atoms and charge balanced is compared with the transformed thermodynamics generally used to treat biochemical reactions where atoms and charges are not balanced. The transformed thermodynamic quantities suggested by Alberty are obtained by execution of Legendre transformation of the usual thermodynamic potentials. The present analysis demonstrates that the transformed values for Δ r G' 0 and Δ r H' 0 can be obtained directly without performing Legendre transformations by simply writing the chemical reactions with all the pseudoisomers explicitly included and charges balanced. The appropriate procedures for computing the stoichiometric coefficients for the pseudoisomers are fully explained by means of an example calculation for the biochemical ATP hydrolysis reaction. It is concluded that the analysis has reunited the "two separate worlds" of conventional thermodynamics and transformed thermodynamics. In addition, it is also shown that the value of the conditional Gibbs energy of reaction, Δ r G', for a biochemical reaction is the same of the value of Δ r G for any chemical reaction involving pseudoisomers of the biochemical reagents. Copyright © 2016 Elsevier B.V. All rights reserved.
A comparative biochemical profile of some cyprinids fish in Dukan Lake, Kurdistan-Iraq
NASA Astrophysics Data System (ADS)
Azeez, Darya Mohammed; Mohammed, Sarbaz Ibrahim
2017-09-01
The present study was carried out to demonstrate the baseline values for some serum biochemical parameters for 64 adult freshwater fish including seven species belong to family Cyprinidae, have been collected in Dukan Lake, Kurdistan region-Iraq. Fishes were weighed, measured, and collect blood for blood chemistry. Serum biochemical analyses were determined using (Cobas C 311) full automatic chemical analyzer. The result of comparative study of serum biochemical parameters of all Cyprinidae species showed that serum glucose was (459.10±106.99 mg/dl) and direct bilirubin was (0.056±0.021mg/dl) in Barbus grypus, serum total protein (3.511± 0.0484gm/dl) and HDL (133.11±0.4231mg/dl) in Cyprinus carpio, serum cholesterol (338.33±43.923 mg/dl) and LDL (86.11±11.871mg/dl) in Carassius carassius, serum triglyceride (420.0±28.8mg/dl) and ALK (113.93±20.65U/L) in Chondrostoma regium, serum AST and serum ALT in Capoeta trutta, were significantly higher when compared to other species. In a conclusion there is variation in biochemical values among species of same family.
Using molecular simulation to explore the nanoscale dynamics of the plant kinome.
Moffett, Alexander S; Shukla, Diwakar
2018-03-09
Eukaryotic protein kinases (PKs) are a large family of proteins critical for cellular response to external signals, acting as molecular switches. PKs propagate biochemical signals by catalyzing phosphorylation of other proteins, including other PKs, which can undergo conformational changes upon phosphorylation and catalyze further phosphorylations. Although PKs have been studied thoroughly across the domains of life, the structures of these proteins are sparsely understood in numerous groups of organisms, including plants. In addition to efforts towards determining crystal structures of PKs, research on human PKs has incorporated molecular dynamics (MD) simulations to study the conformational dynamics underlying the switching of PK function. This approach of experimental structural biology coupled with computational biophysics has led to improved understanding of how PKs become catalytically active and why mutations cause pathological PK behavior, at spatial and temporal resolutions inaccessible to current experimental methods alone. In this review, we argue for the value of applying MD simulation to plant PKs. We review the basics of MD simulation methodology, the successes achieved through MD simulation in animal PKs, and current work on plant PKs using MD simulation. We conclude with a discussion of the future of MD simulations and plant PKs, arguing for the importance of molecular simulation in the future of plant PK research. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.
NASA Astrophysics Data System (ADS)
Kornfeld, A.; Van der Tol, C.; Berry, J. A.
2015-12-01
Recent advances in optical remote sensing of photosynthesis offer great promise for estimating gross primary productivity (GPP) at leaf, canopy and even global scale. These methods -including solar-induced chlorophyll fluorescence (SIF) emission, fluorescence spectra, and hyperspectral features such as the red edge and the photochemical reflectance index (PRI) - can be used to greatly enhance the predictive power of global circulation models (GCMs) by providing better constraints on GPP. The way to use measured optical data to parameterize existing models such as SCOPE (Soil Canopy Observation, Photochemistry and Energy fluxes) is not trivial, however. We have therefore extended a biochemical model to include fluorescence and other parameters in a coupled treatment. To help parameterize the model, we then use nonlinear curve-fitting routines to determine the parameter set that enables model results to best fit leaf-level gas exchange and optical data measurements. To make the tool more accessible to all practitioners, we have further designed a graphical user interface (GUI) based front-end to allow researchers to analyze data with a minimum of effort while, at the same time, allowing them to change parameters interactively to visualize how variation in model parameters affect predicted outcomes such as photosynthetic rates, electron transport, and chlorophyll fluorescence. Here we discuss the tool and its effectiveness, using recently-gathered leaf-level data.
Love, Seth; Miners, J Scott
2017-07-15
The contribution of vascular disease to cognitive impairment is under-recognized and the pathogenesis is poorly understood. This information gap has multiple causes, including a lack of post-mortem validation of clinical diagnoses of vascular cognitive impairment (VCI) or vascular dementia (VaD), the exclusion of cases with concomitant neurodegenerative disease when diagnosing VCI/VaD, and a lack of standardization of neuropathological assessment protocols for vascular disease. Other contributors include a focus on end-stage destructive lesions to the exclusion of more subtle types of diffuse brain injury, on structural abnormalities of arteries and arterioles to the exclusion of non-structural abnormalities and capillary damage, and the use of post-mortem sampling strategies that are biased towards the identification of neurodegenerative pathologies. Recent studies have demonstrated the value of detailed neuropathology in characterizing vascular contributions to cognitive impairment (e.g. in diabetes), and highlight the importance of diffuse white matter changes, capillary damage and vasoregulatory abnormalities in VCI/VaD. The use of standardized, evidence-based post-mortem assessment protocols and the inclusion of biochemical as well as morphological methods in neuropathological studies should improve the accuracy of determination of the contribution of vascular disease to cognitive impairment and clarify the relative contribution of different pathogenic processes to the tissue damage. © 2017 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.
Analytical applications of microbial fuel cells. Part I: Biochemical oxygen demand.
Abrevaya, Ximena C; Sacco, Natalia J; Bonetto, Maria C; Hilding-Ohlsson, Astrid; Cortón, Eduardo
2015-01-15
Microbial fuel cells (MFCs) are bio-electrochemical devices, where usually the anode (but sometimes the cathode, or both) contains microorganisms able to generate and sustain an electrochemical gradient which is used typically to generate electrical power. In the more studied set-up, the anode contains heterotrophic bacteria in anaerobic conditions, capable to oxidize organic molecules releasing protons and electrons, as well as other by-products. Released protons could reach the cathode (through a membrane or not) whereas electrons travel across an external circuit originating an easily measurable direct current flow. MFCs have been proposed fundamentally as electric power producing devices or more recently as hydrogen producing devices. Here we will review the still incipient development of analytical uses of MFCs or related devices or set-ups, in the light of a non-restrictive MFC definition, as promising tools to asset water quality or other measurable parameters. An introduction to biological based analytical methods, including bioassays and biosensors, as well as MFCs design and operating principles, will also be included. Besides, the use of MFCs as biochemical oxygen demand sensors (perhaps the main analytical application of MFCs) is discussed. In a companion review (Part 2), other new analytical applications are reviewed used for toxicity sensors, metabolic sensors, life detectors, and other proposed applications. Copyright © 2014 Elsevier B.V. All rights reserved.
The investigation of serum vaspin level in atherosclerotic coronary artery disease.
Kobat, Mehmet Ali; Celik, Ahmet; Balin, Mehmet; Altas, Yakup; Baydas, Adil; Bulut, Musa; Aydin, Suleyman; Dagli, Necati; Yavuzkir, Mustafa Ferzeyn; Ilhan, Selcuk
2012-04-01
It was speculated that fatty tissue originated adipocytokines may play role in pathogenesis of atherosclerosis. These adipocytokines may alter vascular homeostasis by effecting endothelial cells, arterial smooth muscle cells and macrophages. Vaspin is a newly described member of adipocytokines family. We aimed to investigate whether plasma vaspin level has any predictive value in coronary artery disease (CAD). Forty patients who have at least single vessel ≥ 70 % stenosis demostrated angiographically and 40 subjects with normal coronary anatomy were included to the study. The vaspin levels were measured from serum that is obtained by centrifigation of blood and stored at -20 (o)C by ELISA method. The length, weight and body mass index of patients were measured. Biochemical parameters including total cholesterol, low density lipoprotein, high density lipoprotein, creatinine, sodium, potassium, hemoglobine, uric acid and fasting glucose were also measured. Biochemical markers levels were similar in both groups. Serum vaspin levels were significantly lower in CAD patients than control group (respectively; 256 ± 219 pg/ml vs. 472 ( 564 pg/ml, P < 0.02). Beside this serum vaspin level was lower in control group with high systolic blood pressure. Serum vaspin levels were found significantly lower in patients with CAD than age-matched subjects with normal coronary anatomy. Vaspin may be used as a predictor of CAD. Coronary artery disease; Vaspin; Adipokine.
Silva, Leslie P; Northen, Trent R
2015-08-01
Metabolism is at the heart of many biotechnologies from biofuels to medical diagnostics. Metabolomic methods that provide glimpses into cellular metabolism have rapidly developed into a critical component of the biotechnological development process. Most metabolomics methods have focused on what is happening inside the cell. Equally important are the biochemical transformations of the cell, and their effect on other cells and their environment; the exometabolome. Exometabolomics is therefore gaining popularity as a robust approach for obtaining rich phenotypic data, and being used in bioprocessing and biofuel development. Mass spectrometry imaging approaches, including several nanotechnologies, provide complimentary information by localizing metabolic processes within complex biological matrices. Together, the two technologies can provide new insights into the metabolism and interactions of cells. Published by Elsevier Ltd.
Potts, Barbara C.; Lam, Kin S.
2010-01-01
The salinosporamides are potent proteasome inhibitors among which the parent marine-derived natural product salinosporamide A (marizomib; NPI-0052; 1) is currently in clinical trials for the treatment of various cancers. Methods to generate this class of compounds include fermentation and natural products chemistry, precursor-directed biosynthesis, mutasynthesis, semi-synthesis, and total synthesis. The end products range from biochemical tools for probing mechanism of action to clinical trials materials; in turn, the considerable efforts to produce the target molecules have expanded the technologies used to generate them. Here, the full complement of methods is reviewed, reflecting remarkable contributions from scientists of various disciplines over a period of 7 years since the first publication of the structure of 1. PMID:20479958
Systems biology solutions for biochemical production challenges.
Hansen, Anne Sofie Lærke; Lennen, Rebecca M; Sonnenschein, Nikolaus; Herrgård, Markus J
2017-06-01
There is an urgent need to significantly accelerate the development of microbial cell factories to produce fuels and chemicals from renewable feedstocks in order to facilitate the transition to a biobased society. Methods commonly used within the field of systems biology including omics characterization, genome-scale metabolic modeling, and adaptive laboratory evolution can be readily deployed in metabolic engineering projects. However, high performance strains usually carry tens of genetic modifications and need to operate in challenging environmental conditions. This additional complexity compared to basic science research requires pushing systems biology strategies to their limits and often spurs innovative developments that benefit fields outside metabolic engineering. Here we survey recent advanced applications of systems biology methods in engineering microbial production strains for biofuels and -chemicals. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Maxeiner, Andreas; Kilic, Ergin; Matalon, Julia; Friedersdorff, Frank; Miller, Kurt; Jung, Klaus; Stephan, Carsten; Busch, Jonas
2017-01-01
The purpose of this study was to investigate the Prostate-Health-Index (PHI) for pathological outcome prediction following radical prostatectomy and also for biochemical recurrence prediction in comparison to established parameters such as Gleason-score, pathological tumor stage, resection status (R0/1) and prostate-specific antigen (PSA). Out of a cohort of 460 cases with preoperative PHI-measurements (World Health Organization calibration: Beckman Coulter Access-2-Immunoassay) between 2001 and 2014, 437 patients with complete follow up data were included. From these 437 patients, 87 (19.9%) developed a biochemical recurrence. Patient characteristics were compared by using chi-square test. Predictors were analyzed by multivariate adjusted logistic and Cox regression. The median follow up for a biochemical recurrence was 65 (range 3-161) months. PHI, PSA, [-2]proPSA, PHI- and PSA-density performed as significant variables (p < 0.05) for cancer aggressiveness: Gleason-score <7 or ≥7 (ISUP grade 1 or ≥2) . Concerning pathological tumor stage discrimination and prediction, variables as PHI, PSA, %fPSA, [-2]proPSA, PHI- and PSA-density significantly discriminated between stages
Maxeiner, Andreas; Kilic, Ergin; Matalon, Julia; Friedersdorff, Frank; Miller, Kurt; Jung, Klaus; Stephan, Carsten; Busch, Jonas
2017-10-03
The purpose of this study was to investigate the Prostate-Health-Index (PHI) for pathological outcome prediction following radical prostatectomy and also for biochemical recurrence prediction in comparison to established parameters such as Gleason-score, pathological tumor stage, resection status (R0/1) and prostate-specific antigen (PSA). Out of a cohort of 460 cases with preoperative PHI-measurements (World Health Organization calibration: Beckman Coulter Access-2-Immunoassay) between 2001 and 2014, 437 patients with complete follow up data were included. From these 437 patients, 87 (19.9%) developed a biochemical recurrence. Patient characteristics were compared by using chi-square test. Predictors were analyzed by multivariate adjusted logistic and Cox regression. The median follow up for a biochemical recurrence was 65 (range 3-161) months. PHI, PSA, [-2]proPSA, PHI- and PSA-density performed as significant variables (p < 0.05) for cancer aggressiveness: Gleason-score <7 or ≥7 (ISUP grade 1 or ≥2) . Concerning pathological tumor stage discrimination and prediction, variables as PHI, PSA, %fPSA, [-2]proPSA, PHI- and PSA-density significantly discriminated between stages
Garrahy, A; Casey, R; Wall, D; Bell, M; O'Shea, P M
2015-07-01
Phaeochromocytomas (PC) and paragangliomas (PGL) are rare neuroendocrine tumours of chromaffin cells. Diagnosis depends on biochemical evidence of excessive production of catecholamines. This is straightforward when test results are orders of magnitude above the concentrations expected in healthy individuals and those with essential hypertension. Equivocal results pose a management dilemma. We reviewed biochemical screens that were positive and the ensuing management for PC/PGL at our institution. The objective was to inform the development of a standardised approach to investigation and clinical follow-up. All records of positive biochemical screening for PC/PGL were extracted from the laboratory information system between January 2004 and June 2012. Clinical notes of patients with positive results were reviewed. A total of 2749 biochemical screens were performed during the evaluation period. Of these, 106 (3.9%) performed on 82 patients were positive. Chart review determined that 12/82 patients had histologically confirmed PC/PG. Of the 70 patients remaining, the most common indication for biochemical screening was hypertension and the medical subspecialty most frequently requesting the test was Endocrinology. The primary team carried out repeat testing on 35/70 (50%) patients and in 29 results normalised. Notably, 35/70 (50%) patients did not have any follow-up of positive test results. This study highlights the necessity for a standardised diagnostic protocol for PC/PGL. We suggest that appropriate follow-up of borderline-elevated results should first include repeat biochemical testing. This should be performed under standardised pre-analytical conditions and where possible off all potentially interfering medications, measuring plasma free metadrenalines. © 2015 John Wiley & Sons Ltd.
Sibley, Christopher D; Peirano, Gisele; Church, Deirdre L
2012-04-01
Clinical microbiology laboratories worldwide have historically relied on phenotypic methods (i.e., culture and biochemical tests) for detection, identification and characterization of virulence traits (e.g., antibiotic resistance genes, toxins) of human pathogens. However, limitations to implementation of molecular methods for human infectious diseases testing are being rapidly overcome allowing for the clinical evaluation and implementation of diverse technologies with expanding diagnostic capabilities. The advantages and limitation of molecular techniques including real-time polymerase chain reaction, partial or whole genome sequencing, molecular typing, microarrays, broad-range PCR and multiplexing will be discussed. Finally, terminal restriction fragment length polymorphism (T-RFLP) and deep sequencing are introduced as technologies at the clinical interface with the potential to dramatically enhance our ability to diagnose infectious diseases and better define the epidemiology and microbial ecology of a wide range of complex infections. Copyright © 2012 Elsevier B.V. All rights reserved.
[Experimental rationale for the parameters of a rapid method for oxidase activity determination].
Butorina, N N
2010-01-01
Experimental rationale is provided for the parameters of a rapid (1-2-min) test to concurrently determine the oxidase activity of all bacteria grown on the membrane filter after water filtration. Oxidase reagents that are the aqueous solutions of tetramethyl-p-phenylenediamine dihydrochloride and demethyl-p-phenylenediamine dihydrochloride have been first ascertained to exert no effect on the viability and enzymatic activity of bacteria after one-hour contact. An algorithm has been improved for the rapid oxidase activity test: the allowable time for bacteria to contact oxidase reagents and procedures for minimizing the effect on bacterial biochemical activity following the contact. An accelerated method based on lactose medium with tergitol 7 and Endo agar has been devised to determine coliform bacteria, by applying the rapid oxidase test: the time of a final response is 18-24 hours. The method has been included into GOST 52426-2005.
Green methods of lignocellulose pretreatment for biorefinery development.
Capolupo, Laura; Faraco, Vincenza
2016-11-01
Lignocellulosic biomass is the most abundant, low-cost, bio-renewable resource that holds enormous importance as alternative source for production of biofuels and other biochemicals that can be utilized as building blocks for production of new materials. Enzymatic hydrolysis is an essential step involved in the bioconversion of lignocellulose to produce fermentable monosaccharides. However, to allow the enzymatic hydrolysis, a pretreatment step is needed in order to remove the lignin barrier and break down the crystalline structure of cellulose. The present manuscript is dedicated to reviewing the most commonly applied "green" pretreatment processes used in bioconversion of lignocellulosic biomasses within the "biorefinery" concept. In this frame, the effects of different pretreatment methods on lignocellulosic biomass are described along with an in-depth discussion on the benefits and drawbacks of each method, including generation of potentially inhibitory compounds for enzymatic hydrolysis, effect on cellulose digestibility, and generation of compounds toxic for the environment, and energy and economic demand.
Immunoelectrophoresis: a method with many faces.
Csako, Gyorgy
2012-01-01
Immunoelectrophoresis (IEP) was the first practical method that combined electrophoresis and -immunoprecipitation for identifying and characterizing proteins within complex mixtures. Over the years, IEP has been extended to include a variety of techniques and, as a general name, has been applied to virtually any technique that involves electrophoresis and antigen-antibody precipitin reaction for proteins. Because of the diversity in technical details of different IEP versions, the method described here deals only with classic IEP. Although it requires some manual expertise, IEP is versatile, relatively easy to customize, and economical with no need for expensive instrumentation. Further, it can discern identity, partial identity, and nonidentity of the proteins. Any low-viscosity body fluid specimen or, possibly, culture fluid and tissue extract could be tested with IEP if proper antibodies are available. With these attributes, classic IEP remains a valuable tool for clinical diagnostic testing, purity checking of biochemical and pharmaceutical products, and research.
Isolation of purified oocyst walls and sporocysts from Toxoplasma gondii.
Everson, William V; Ware, Michael W; Dubey, J P; Lindquist, H D Alan
2002-01-01
Toxoplasma gondii oocysts are environmentally resistant and can infect virtually all warm-blooded hosts, including humans and livestock. Little is known about the biochemical basis for this resistance of oocysts, and mechanism for excystation of T. gondii sporozoites. The objective of the present study was to evaluate different methods (mechanical fragmentation, gradients, flow cytometry) to separate and purify T. gondii oocyst walls and sporocysts. Oocyst walls were successfully separated and purified using iodixanol gradients. Sporocysts were successfully separated and purified using iodixanol and Percoll gradients. Purification was also achieved by flow cytometry. Flow cytometry with fluorescence-activated cell sorting (FACS) yielded analytical quantities of oocyst walls and intact sporocysts. Flow cytometry with FACS also proved useful for quantitation of purity obtained following iodixanol gradient fractionation. Methods reported in this paper will be useful for analytical purposes, such as proteomic analysis of components unique to this life cycle stage, development of detection methods, or excystation studies.
Myjak, P; Majewska, A C; Bajer, A; Siński, E; Wedrychowicz, H; Gołab, E; Budak, A; Stańczak, J
2001-01-01
After a long period of using basic microscopic, immunological and biochemical methods for diagnosis, rapid development of nucleic acids investigation enabled introduction of specific and sensitive methods of detection of pathogenic agents on the molecular level. Among others, polymerase chain reaction (PCR), discovered in mid of 80'ies and then automatized, offered an attractive alternative to conventional testing systems. In this paper we describe reliable diagnostic tests widely used in the world, including Poland, and capable of detecting different disease agents as parasites and fungi in clinical specimens and pathogens of emerging zoonotic diseases in ticks. The possibilities of using molecular methods for determination of Plasmodium falciparum drug resistance is also discussed. Moreover, the report offers information concerning kinds of molecular tests and institutions in which there are executed.
NASA Technical Reports Server (NTRS)
Shapiro, Bruce E.; Levchenko, Andre; Meyerowitz, Elliot M.; Wold, Barbara J.; Mjolsness, Eric D.
2003-01-01
Cellerator describes single and multi-cellular signal transduction networks (STN) with a compact, optionally palette-driven, arrow-based notation to represent biochemical reactions and transcriptional activation. Multi-compartment systems are represented as graphs with STNs embedded in each node. Interactions include mass-action, enzymatic, allosteric and connectionist models. Reactions are translated into differential equations and can be solved numerically to generate predictive time courses or output as systems of equations that can be read by other programs. Cellerator simulations are fully extensible and portable to any operating system that supports Mathematica, and can be indefinitely nested within larger data structures to produce highly scaleable models.
Identification of medically relevant Nocardia species with an abbreviated battery of tests.
Kiska, Deanna L; Hicks, Karen; Pettit, David J
2002-04-01
Identification of Nocardia to the species level is useful for predicting antimicrobial susceptibility patterns and defining the pathogenicity and geographic distribution of these organisms. We sought to develop an identification method which was accurate, timely, and employed tests which would be readily available in most clinical laboratories. We evaluated the API 20C AUX yeast identification system as well as several biochemical tests and Kirby-Bauer susceptibility patterns for the identification of 75 isolates encompassing the 8 medically relevant Nocardia species. There were few biochemical reactions that were sufficiently unique for species identification; of note, N. nova were positive for arylsulfatase, N. farcinica were positive for opacification of Middlebrook 7H11 agar, and N. brasiliensis and N. pseudobrasiliensis were the only species capable of liquefying gelatin. API 20C sugar assimilation patterns were unique for N. transvalensis, N. asteroides IV, and N. brevicatena. There was overlap among the assimilation patterns for the other species. Species-specific patterns of susceptibility to gentamicin, tobramycin, amikacin, and erythromycin were obtained for N. nova, N. farcinica, and N. brevicatena, while there was overlap among the susceptibility patterns for the other isolates. No single method could identify all Nocardia isolates to the species level; therefore, a combination of methods was necessary. An algorithm utilizing antibiotic susceptibility patterns, citrate utilization, acetamide utilization, and assimilation of inositol and adonitol accurately identified all isolates. The algorithm was expanded to include infrequent drug susceptibility patterns which have been reported in the literature but which were not seen in this study.
Reverse engineering time discrete finite dynamical systems: a feasible undertaking?
Delgado-Eckert, Edgar
2009-01-01
With the advent of high-throughput profiling methods, interest in reverse engineering the structure and dynamics of biochemical networks is high. Recently an algorithm for reverse engineering of biochemical networks was developed by Laubenbacher and Stigler. It is a top-down approach using time discrete dynamical systems. One of its key steps includes the choice of a term order, a technicality imposed by the use of Gröbner-bases calculations. The aim of this paper is to identify minimal requirements on data sets to be used with this algorithm and to characterize optimal data sets. We found minimal requirements on a data set based on how many terms the functions to be reverse engineered display. Furthermore, we identified optimal data sets, which we characterized using a geometric property called "general position". Moreover, we developed a constructive method to generate optimal data sets, provided a codimensional condition is fulfilled. In addition, we present a generalization of their algorithm that does not depend on the choice of a term order. For this method we derived a formula for the probability of finding the correct model, provided the data set used is optimal. We analyzed the asymptotic behavior of the probability formula for a growing number of variables n (i.e. interacting chemicals). Unfortunately, this formula converges to zero as fast as , where and . Therefore, even if an optimal data set is used and the restrictions in using term orders are overcome, the reverse engineering problem remains unfeasible, unless prodigious amounts of data are available. Such large data sets are experimentally impossible to generate with today's technologies.
Clinical and biochemical changes in 53 Swedish dogs bitten by the European adder - Vipera berus
2010-01-01
Background Every year many dogs in Sweden are bitten by Vipera berus, the only venomous viper in Sweden. This prospective study investigated clinical signs, some biochemical parameters, treatment, and progress of disease after snakebite in 53 dogs. Effects of treatment with and without glucocorticoids were evaluated. Methods All fifty-three dogs bitten by Vipera berus were examined the same day the dog was bitten and the next day. Two more examinations during 23 days post snake bite were included. Creatinine, creatine kinase (CK), alanine aminotransferase (ALT), glutamate dehydrogenase (GLDH), alkaline phosphatase (ALP) and bile acid results were followed through 3 to 4 samplings from 34 of the dogs. Results All dogs had variable severity of local swelling in the bite area and 73 per cent had affected mental status. Initial cardiac auscultation examination was normal in all dogs, but six dogs had cardiac abnormalities at their second examination, including cardiac arrhythmias and cardiac murmurs. All dogs received fluid therapy, 36 dogs were given analgesics, 22 dogs were treated with glucocorticoids, and ten dogs were treated with antibiotics. Evidence of transient muscle damage (increased CK) was seen one day after the snake bite in 15 (54%) of 28 sampled dogs. Moderate changes in hepatic test results occurred in 1 dog and several dogs (22 of 34) had transient, minor increases in one or more hepatic test result. No dog died during the observation period as a consequence of the snake bite. Conclusions Snake bite caused local swelling in all dogs and mental depression of short duration in most dogs. Some dogs had transient clinical signs that could be indicative of cardiac injury and some other had transient biochemical signs of liver injury. Treatment with glucocorticoids did not have any clear positive or negative effect on clinical signs and mortality. PMID:20416040
Lazarevic, Ivana; Stevanovic, Goran; Cirkovic, Andja; Karalic, Danijela; Cupic, Maja; Banko, Bojan; Milovanovic, Jovica; Jovanovic, Tanja
2016-01-01
Summary Background Primary Epstein-Barr virus (EBV) infection is usually asymptomatic, although at times it results in the benign lymphoproliferative disease, infectious mononucleosis (IM), during which almost half of patients develop hepatitis. The aims of the present study are to evaluate polymorphisms of EBV genes circulating in IM isolates from this geographic region and to investigate the correlation of viral sequence patterns with the available IM biochemical parameters. Methods The study included plasma samples from 128 IM patients. The genes EBNA2, LMP1, and EBNA1 were amplified using nested-PCR. EBNA2 genotyping was performed by visualization of PCR products using gel electrophoresis. Investigation of LMP1 and EBNA1 included sequence, phylogenetic, and statistical analyses. Results The presence of EBV DNA in plasma samples showed correlation with patients’ necessity for hospitalization (p=0.034). The majority of EBV isolates was genotype 1. LMP1 variability showed 4 known variants, and two new deletions (27-bp and 147-bp). Of the 3 analyzed attributes of LMP1 isolates, the number of 33-bp repeats less than the reference 4.5 was the only one that absolutely correlated with the elevated levels of transaminases. EBNA1 variability was presented by prototype subtypes. A particular combination of EBNA2, LMP1, and EBNA1 polymorphisms, deleted LMP1/P-thr and non-deleted LMP1/P-ala, as well as genotype 1/ 4.5 33-bp LMP1 repeats or genotype 2/ 4.5 33-bp LMP1 repeats showed correlation with elevated AST (aspartate aminotransferase) and ALT (alanine transaminase). Conclusions This is the first study which identified the association between EBV variability and biochemical parameters in IM patients. These results showed a possibility for the identification of hepatic related diagnostic EBV markers. PMID:28356886
Identification of biochemical features of defective Coffea arabica L. beans.
Casas, María I; Vaughan, Michael J; Bonello, Pierluigi; McSpadden Gardener, Brian; Grotewold, Erich; Alonso, Ana P
2017-05-01
Coffee organoleptic properties are based in part on the quality and chemical composition of coffee beans. The presence of defective beans during processing and roasting contribute to off flavors and reduce overall cup quality. A multipronged approach was undertaken to identify specific biochemical markers for defective beans. To this end, beans were split into defective and non-defective fractions and biochemically profiled in both green and roasted states. A set of 17 compounds in green beans, including organic acids, amino acids and reducing sugars; and 35 compounds in roasted beans, dominated by volatile compounds, organic acids, sugars and sugar alcohols, were sufficient to separate the defective and non-defective fractions. Unsorted coffee was examined for the presence of the biochemical markers to test their utility in detecting defective beans. Although the green coffee marker compounds were found in all fractions, three of the roasted coffee marker compounds (1-methylpyrrole, 5-methyl- 2-furfurylfuran, and 2-methylfuran) were uniquely present in defective fractions. Published by Elsevier Ltd.
Biochemical Diagnosis in Substance and Non-substance Addiction.
Shen, Wenwen; Liu, Huifeng; Xie, Xiaohu; Liu, Haixiong; Zhou, Wenhua
2017-01-01
An optimal biochemical marker for addiction would be some easily traced molecules in body specimens, which indicates indulgent addictive behaviors, or susceptibility to certain addictive stimuli. In this chapter, we discussed existing literature about possible biomarkers, and classified them into three categories: origin forms and metabolites of substances, markers from biochemical responses to certain addiction, and genetic and epigenetic biomarkers suggesting susceptibility to addiction. In every category, we examined studies concerning certain type of addiction one by one, with focuses mainly on opiates, psychostimulants, and pathological gambling. Several promising molecules were highlighted, including those of neurotrophic factors, inflammatory factors, and indicators of vascular injury, and genetic and epigenetic biomarkers such as serum miRNAs. DNA methylation signatures and signal nucleotide polymorphism of candidate gene underlying the addiction.
NASA Astrophysics Data System (ADS)
Anikushina, V.; Taratukhin, V.; Stutterheim, C. v.; Gushin, V.
2018-02-01
A new psycholinguistic view on the crew communication, combined with biochemical and psychological data, contributes to noninvasive methods for stress appraisal and proposes alternative approaches to improve in-group communication and cohesion.
Mohammadi, Samira; Esfahani, Bahram Nasr; Moghim, Sharareh; Mirhendi, Hossein; Zaniani, Fatemeh Riyahi; Safaei, Hajieh Ghasemian; Fazeli, Hossein; Salehi, Mahshid
2017-01-01
Nontuberculous mycobacteria (NTM) are a group of opportunistic pathogens and these are widely dispersed in water and soil resources. Identification of mycobacteria isolates by conventional methods including biochemical tests, growth rates, colony pigmentation, and presence of acid-fast bacilli is widely used, but these methods are time-consuming, labor-intensive, and may sometimes remain inconclusive. The DNA was extracted from NTM cultures using CTAB, Chelex, Chelex + Nonidet P-40, FTA ® Elute card, and boiling The quantity and quality of the DNA extracted via these methods were determined using UV-photometer at 260 and 280 nm, and polymerase chain reaction (PCR) amplification of the heat-shock protein 65 gene with serially diluted DNA samples. The CTAB method showed more positive results at 1:10-1:100,000 at which the DNA amount was substantial. With the Chelex method of DNA extraction, PCR amplification was detected at 1:10 and 1:1000 dilutions. According to the electrophoresis results, the CTAB and Chelex DNA extraction methods were more successful in comparison with the others as regard producing suitable concentrations of DNA with the minimum use of PCR inhibitor.
Ahmed, W; Stewart, J; Gardner, T; Powell, D; Brooks, P; Sullivan, D; Tindale, N
2007-08-01
Library-dependent (LD) (biochemical fingerprinting of Escherichia coli and enterococci) and library-independent (LI) (PCR detection of human-specific biomarkers) methods were used to detect human faecal pollution in three non-sewered catchments. In all, 550 E. coli isolates and 700 enterococci isolates were biochemically fingerprinted from 18 water samples and compared with metabolic fingerprint libraries of 4508 E. coli and 4833 enterococci isolates. E. coli fingerprints identified human unique biochemical phenotypes (BPTs) in nine out of 18 water samples; similarly, enterococci fingerprints identified human faecal pollution in 10 water samples. Seven samples were tested by PCR for the detection of biomarkers. Human-specific HF134 Bacteroides and enterococci surface protein (esp) biomarkers were detected in five samples. Four samples were also positive for HF183 Bacteroides biomarker. The combination of biomarkers detected human faecal pollution in six out of seven water samples. Of the seven samples analysed for both the indicators/markers, at least one indicator/marker was detected in every sample. Four of the seven PCR-positive samples were also positive for one of the human-specific E. coli or enterococci BPTs. The results indicated human faecal pollution in the studied sub-catchments after storm events. LD and LI methods used in this study complimented each other and provided additional information regarding the polluting sources when one method failed to detect human faecal pollution. Therefore, it is recommended that a combination of methods should be used to identify the source(s) of faecal pollution where possible.
X-ray crystallography over the past decade for novel drug discovery – where are we heading next?
Zheng, Heping; Handing, Katarzyna B; Zimmerman, Matthew D; Shabalin, Ivan G; Almo, Steven C; Minor, Wladek
2015-01-01
Introduction Macromolecular X-ray crystallography has been the primary methodology for determining the three-dimensional structures of proteins, nucleic acids and viruses. Structural information has paved the way for structure-guided drug discovery and laid the foundations for structural bioinformatics. However, X-ray crystallography still has a few fundamental limitations, some of which may be overcome and complemented using emerging methods and technologies in other areas of structural biology. Areas covered This review describes how structural knowledge gained from X-ray crystallography has been used to advance other biophysical methods for structure determination (and vice versa). This article also covers current practices for integrating data generated by other biochemical and biophysical methods with those obtained from X-ray crystallography. Finally, the authors articulate their vision about how a combination of structural and biochemical/biophysical methods may improve our understanding of biological processes and interactions. Expert opinion X-ray crystallography has been, and will continue to serve as, the central source of experimental structural biology data used in the discovery of new drugs. However, other structural biology techniques are useful not only to overcome the major limitation of X-ray crystallography, but also to provide complementary structural data that is useful in drug discovery. The use of recent advancements in biochemical, spectroscopy and bioinformatics methods may revolutionize drug discovery, albeit only when these data are combined and analyzed with effective data management systems. Accurate and complete data management is crucial for developing experimental procedures that are robust and reproducible. PMID:26177814
Multiscale Hy3S: hybrid stochastic simulation for supercomputers.
Salis, Howard; Sotiropoulos, Vassilios; Kaznessis, Yiannis N
2006-02-24
Stochastic simulation has become a useful tool to both study natural biological systems and design new synthetic ones. By capturing the intrinsic molecular fluctuations of "small" systems, these simulations produce a more accurate picture of single cell dynamics, including interesting phenomena missed by deterministic methods, such as noise-induced oscillations and transitions between stable states. However, the computational cost of the original stochastic simulation algorithm can be high, motivating the use of hybrid stochastic methods. Hybrid stochastic methods partition the system into multiple subsets and describe each subset as a different representation, such as a jump Markov, Poisson, continuous Markov, or deterministic process. By applying valid approximations and self-consistently merging disparate descriptions, a method can be considerably faster, while retaining accuracy. In this paper, we describe Hy3S, a collection of multiscale simulation programs. Building on our previous work on developing novel hybrid stochastic algorithms, we have created the Hy3S software package to enable scientists and engineers to both study and design extremely large well-mixed biological systems with many thousands of reactions and chemical species. We have added adaptive stochastic numerical integrators to permit the robust simulation of dynamically stiff biological systems. In addition, Hy3S has many useful features, including embarrassingly parallelized simulations with MPI; special discrete events, such as transcriptional and translation elongation and cell division; mid-simulation perturbations in both the number of molecules of species and reaction kinetic parameters; combinatorial variation of both initial conditions and kinetic parameters to enable sensitivity analysis; use of NetCDF optimized binary format to quickly read and write large datasets; and a simple graphical user interface, written in Matlab, to help users create biological systems and analyze data. We demonstrate the accuracy and efficiency of Hy3S with examples, including a large-scale system benchmark and a complex bistable biochemical network with positive feedback. The software itself is open-sourced under the GPL license and is modular, allowing users to modify it for their own purposes. Hy3S is a powerful suite of simulation programs for simulating the stochastic dynamics of networks of biochemical reactions. Its first public version enables computational biologists to more efficiently investigate the dynamics of realistic biological systems.
NASA Technical Reports Server (NTRS)
Lane, Helen W.; Whitson, Peggy A.; Putcha, Lakshmi; Baker, Ellen; Smith, Scott M.; Stewart, Karen; Gretebeck, Randall; Nimmagudda, R. R.; Schoeller, Dale A.; Davis-Street, Janis
1999-01-01
As noted elsewhere in this report, a central goal of the Extended Duration Orbiter Medical Project (EDOMP) was to ensure that cardiovascular and muscle function were adequate to perform an emergency egress after 16 days of spaceflight. The goals of the Regulatory Physiology component of the EDOMP were to identify and subsequently ameliorate those biochemical and nutritional factors that deplete physiological reserves or increase risk for disease, and to facilitate the development of effective muscle, exercise, and cardiovascular countermeasures. The component investigations designed to meet these goals focused on biochemical and physiological aspects of nutrition and metabolism, the risk of renal (kidney) stone formation, gastrointestinal function, and sleep in space. Investigations involved both ground-based protocols to validate proposed methods and flight studies to test those methods. Two hardware tests were also completed.
Potential of FTIR spectroscopy for analysis of tears for diagnosis purposes.
Travo, Adrian; Paya, Clément; Déléris, Gérard; Colin, Joseph; Mortemousque, Bruno; Forfar, Isabelle
2014-04-01
It has been widely reported that the tear film, which is crucially important as a protective barrier of the eye, undergoes biochemical changes as a result of a wide range of ocular pathology. This tends to suggest the possibility of early detection of ocular diseases on the basis of biochemical analysis of tears. However, studies of tears by conventional methods of biomolecular and biochemical analysis are often limited by methodological difficulties. Moreover, such analysis could not be applied in the clinic, where structural and morphological analyses by, mainly, slit-lamp biomicroscopy remains the recommended method. In this study, we assessed, for the first time, the potential of FTIR spectroscopy combined with advanced chemometric processing of spectral data for analysis of raw tears for diagnosis purposes. We first optimized sampling and spectral acquisition (tears collection method, tear sample volume, and preservation of the samples) for accurate spectral measurement. On the basis of the results, we focused our study on the possibility of discriminating tears from normal individuals from those of patients with different ocular pathologies, and showed that the most discriminating spectral range is that corresponding to variations of CH2 and CH3 of lipid aliphatic chains. We also report more subtle discrimination of tears from patients with keratoconus and those from patients with non-specific inflammatory ocular diseases, on the basis of variations in spectral ranges attributed notably to lipid and carbohydrate vibrations. Finally, we also succeeded in distinguishing tears from patients with early-stage and late-stage keratoconus on the basis of spectral features attributed to protein structure. Therefore, this study strongly suggests that FTIR spectral analysis of tears could be developed as a valuable and cost-saving tool for biochemical-based detection of ocular diseases, potentially before the appearance of the first morphological signs of diseases. Combined with supervised modelling methods and with use of a spectral data base acquired for representative patients, such a spectral approach could be a useful addition to current methods of clinical analysis for improvement of patient care.
Estimating rare events in biochemical systems using conditional sampling.
Sundar, V S
2017-01-28
The paper focuses on development of variance reduction strategies to estimate rare events in biochemical systems. Obtaining this probability using brute force Monte Carlo simulations in conjunction with the stochastic simulation algorithm (Gillespie's method) is computationally prohibitive. To circumvent this, important sampling tools such as the weighted stochastic simulation algorithm and the doubly weighted stochastic simulation algorithm have been proposed. However, these strategies require an additional step of determining the important region to sample from, which is not straightforward for most of the problems. In this paper, we apply the subset simulation method, developed as a variance reduction tool in the context of structural engineering, to the problem of rare event estimation in biochemical systems. The main idea is that the rare event probability is expressed as a product of more frequent conditional probabilities. These conditional probabilities are estimated with high accuracy using Monte Carlo simulations, specifically the Markov chain Monte Carlo method with the modified Metropolis-Hastings algorithm. Generating sample realizations of the state vector using the stochastic simulation algorithm is viewed as mapping the discrete-state continuous-time random process to the standard normal random variable vector. This viewpoint opens up the possibility of applying more sophisticated and efficient sampling schemes developed elsewhere to problems in stochastic chemical kinetics. The results obtained using the subset simulation method are compared with existing variance reduction strategies for a few benchmark problems, and a satisfactory improvement in computational time is demonstrated.
Recent Advances on the Use of Biochemical Extracts as Filaricidal Agents
Al-Abd, Nazeh M.; Nor, Zurainee Mohamed; Al-Adhroey, Abdulelah H.; Suhaimi, Anwar; Sivanandam, S.
2013-01-01
Lymphatic filariasis is a parasitic infection that causes a devastating public health and socioeconomic burden with an estimated infection of over 120 million individuals worldwide. The infection is caused by three closely related nematode parasites, namely, Wuchereria bancrofti, Brugia malayi, and B. timori, which are transmitted to human through mosquitoes of Anopheles, Culex, and Aedes genera. The species have many ecological variants and are diversified in terms of their genetic fingerprint. The rapid spread of the disease and the genetic diversification cause the lymphatic filarial parasites to respond differently to diagnostic and therapeutic interventions. This in turn prompts the current challenge encountered in its management. Furthermore, most of the chemical medications used are characterized by adverse side effects. These complications urgently warrant intense prospecting on bio-chemicals that have potent efficacy against either the filarial worms or thier vector. In lieu of this, we presented a review on recent literature that reported the efficacy of filaricidal biochemicals and those employed as vector control agents. In addition, methods used for biochemical extraction, screening procedures, and structure of the bioactive compounds were also presented. PMID:24298292
Stable isotope probing to study functional components of complex microbial ecosystems.
Mazard, Sophie; Schäfer, Hendrik
2014-01-01
This protocol presents a method of dissecting the DNA or RNA of key organisms involved in a specific biochemical process within a complex ecosystem. Stable isotope probing (SIP) allows the labelling and separation of nucleic acids from community members that are involved in important biochemical transformations, yet are often not the most numerically abundant members of a community. This pure culture-independent technique circumvents limitations of traditional microbial isolation techniques or data mining from large-scale whole-community metagenomic studies to tease out the identities and genomic repertoires of microorganisms participating in biological nutrient cycles. SIP experiments can be applied to virtually any ecosystem and biochemical pathway under investigation provided a suitable stable isotope substrate is available. This versatile methodology allows a wide range of analyses to be performed, from fatty-acid analyses, community structure and ecology studies, and targeted metagenomics involving nucleic acid sequencing. SIP experiments provide an effective alternative to large-scale whole-community metagenomic studies by specifically targeting the organisms or biochemical transformations of interest, thereby reducing the sequencing effort and time-consuming bioinformatics analyses of large datasets.
ENZYME DISTRIBUTION IN THE RAT FETUS AND PLACENTA FOLLOWING THE ADMINSTRATION OF ETHIONINE
Schultz, Richard L.; Schultz, Phyllis W.
1962-01-01
Enzyme changes which accompany ethionine-induced resorption of the rat conceptus have been studied by both histochemical and biochemical techniques. Pregnant rats were injected with ethionine over a 3-day period prior to autopsy on day 12 of pregnancy. Sections of the whole conceptus were studied for acid phosphatase with both the Burstone and Gomori methods and for succinoxidase activity with nitro-BT. Biochemical determinations of cathepsins, acid phosphatase, and succinoxidase were performed on homogenates of the fetuses, placentae, and deciduas basalis from ethionine-treated and saline-treated rats. The histochemical study has shown that resorption is accompanied by an increase in the size and number of acid phosphatase granules in the decidual tissues and a concurrent loss of acid phosphatase granules in the fetal tissues. Biochemical methodology indicated that there was no increase in total cathepsin or acid phosphatase activities in the resorbing tissues. No change in succinoxidase activity was found with either histochemical or biochemical techniques. The significance of these results was discussed with reference to the lysosome hypothesis. PMID:13987236
NASA Astrophysics Data System (ADS)
Herath, Narmada; Del Vecchio, Domitilla
2018-03-01
Biochemical reaction networks often involve reactions that take place on different time scales, giving rise to "slow" and "fast" system variables. This property is widely used in the analysis of systems to obtain dynamical models with reduced dimensions. In this paper, we consider stochastic dynamics of biochemical reaction networks modeled using the Linear Noise Approximation (LNA). Under time-scale separation conditions, we obtain a reduced-order LNA that approximates both the slow and fast variables in the system. We mathematically prove that the first and second moments of this reduced-order model converge to those of the full system as the time-scale separation becomes large. These mathematical results, in particular, provide a rigorous justification to the accuracy of LNA models derived using the stochastic total quasi-steady state approximation (tQSSA). Since, in contrast to the stochastic tQSSA, our reduced-order model also provides approximations for the fast variable stochastic properties, we term our method the "stochastic tQSSA+". Finally, we demonstrate the application of our approach on two biochemical network motifs found in gene-regulatory and signal transduction networks.
Current Challenges in Plant Eco-Metabolomics
Peters, Kristian; Worrich, Anja; Alka, Oliver; Balcke, Gerd; Bruelheide, Helge; Dietz, Sophie; Dührkop, Kai; Heinig, Uwe; Kücklich, Marlen; Müller, Caroline; Poeschl, Yvonne; Pohnert, Georg; Ruttkies, Christoph; Schweiger, Rabea; Shahaf, Nir; Tortosa, Maria; Ueberschaar, Nico; Velasco, Pablo; Weiß, Brigitte M.; van Dam, Nicole M.
2018-01-01
The relatively new research discipline of Eco-Metabolomics is the application of metabolomics techniques to ecology with the aim to characterise biochemical interactions of organisms across different spatial and temporal scales. Metabolomics is an untargeted biochemical approach to measure many thousands of metabolites in different species, including plants and animals. Changes in metabolite concentrations can provide mechanistic evidence for biochemical processes that are relevant at ecological scales. These include physiological, phenotypic and morphological responses of plants and communities to environmental changes and also interactions with other organisms. Traditionally, research in biochemistry and ecology comes from two different directions and is performed at distinct spatiotemporal scales. Biochemical studies most often focus on intrinsic processes in individuals at physiological and cellular scales. Generally, they take a bottom-up approach scaling up cellular processes from spatiotemporally fine to coarser scales. Ecological studies usually focus on extrinsic processes acting upon organisms at population and community scales and typically study top-down and bottom-up processes in combination. Eco-Metabolomics is a transdisciplinary research discipline that links biochemistry and ecology and connects the distinct spatiotemporal scales. In this review, we focus on approaches to study chemical and biochemical interactions of plants at various ecological levels, mainly plant–organismal interactions, and discuss related examples from other domains. We present recent developments and highlight advancements in Eco-Metabolomics over the last decade from various angles. We further address the five key challenges: (1) complex experimental designs and large variation of metabolite profiles; (2) feature extraction; (3) metabolite identification; (4) statistical analyses; and (5) bioinformatics software tools and workflows. The presented solutions to these challenges will advance connecting the distinct spatiotemporal scales and bridging biochemistry and ecology. PMID:29734799
2016-01-01
Inflammation response plays an important role in host survival, and it also leads to acute and chronic inflammatory diseases such as rheumatoid arthritis, bowel diseases, allergic rhinitis, asthma, atopic dermatitis and various neurodegenerative diseases. During the course of inflammation, the ROS level increases. In addition to ROS, several inflammatory mediators produced at the site lead to numerous cell-mediated damages. Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is a chronic intestinal disorder resulting from a dysfunctional epithelial, innate and adaptive immune response to intestinal microorganisms. The methods involving indomethacin-induced enterocolitis in rats with macroscopic changes of IBD, myeloperoxidase assay, microscopic (histologic) characters and biochemical parameters are discussed.
Chemical and Biochemical Approaches in the Study of Histone Methylation and Demethylation
Li, Keqin Kathy; Luo, Cheng; Wang, Dongxia; Jiang, Hualiang; Zheng, Y. George
2014-01-01
Histone methylation represents one of the most critical epigenetic events in DNA function regulation in eukaryotic organisms. Classic molecular biology and genetics tools provide significant knowledge about mechanisms and physiological roles of histone methyltransferases and demethylases in various cellular processes. In addition to this stream line, development and application of chemistry and chemistry-related techniques are increasingly involved in biological study, and provide information otherwise difficulty to obtain by standard molecular biology methods. Herein, we review recent achievements and progress in developing and applying chemical and biochemical approaches in the study of histone methylation, including chromatin immunoprecipitation (ChIP), chemical ligation, mass spectrometry (MS), biochemical assays, and inhibitor development. These technological advances allow histone methylation to be studied from genome-wide level to molecular and atomic levels. With ChIP technology, information can be obtained about precise mapping of histone methylation patterns at specific promoters, genes or other genomic regions. MS is particularly useful in detecting and analyzing methylation marks in histone and nonhistone protein substrates. Chemical approaches that permit site-specific incorporation of methyl groups into histone proteins greatly facilitate the investigation of the biological impacts of methylation at individual modification sites. Discovery and design of selective organic inhibitors of histone methyltransferases and demethylases provide chemical probes to interrogate methylation-mediated cellular pathways. Overall, these chemistry-related technological advances have greatly improved our understanding of the biological functions of histone methylation in normal physiology and diseased states, and also are of great potential to translate basic epigenetics research into diagnostic and therapeutic application in the clinic. PMID:22777714
Neurochemical profile of dementia pugilistica.
Kokjohn, Tyler A; Maarouf, Chera L; Daugs, Ian D; Hunter, Jesse M; Whiteside, Charisse M; Malek-Ahmadi, Michael; Rodriguez, Emma; Kalback, Walter; Jacobson, Sandra A; Sabbagh, Marwan N; Beach, Thomas G; Roher, Alex E
2013-06-01
Dementia pugilistica (DP), a suite of neuropathological and cognitive function declines after chronic traumatic brain injury (TBI), is present in approximately 20% of retired boxers. Epidemiological studies indicate TBI is a risk factor for neurodegenerative disorders including Alzheimer disease (AD) and Parkinson disease (PD). Some biochemical alterations observed in AD and PD may be recapitulated in DP and other TBI persons. In this report, we investigate long-term biochemical changes in the brains of former boxers with neuropathologically confirmed DP. Our experiments revealed biochemical and cellular alterations in DP that are complementary to and extend information already provided by histological methods. ELISA and one-dimensional and two dimensional Western blot techniques revealed differential expression of select molecules between three patients with DP and three age-matched non-demented control (NDC) persons without a history of TBI. Structural changes such as disturbances in the expression and processing of glial fibrillary acidic protein, tau, and α-synuclein were evident. The levels of the Aβ-degrading enzyme neprilysin were reduced in the patients with DP. Amyloid-β levels were elevated in the DP participant with the concomitant diagnosis of AD. In addition, the levels of brain-derived neurotrophic factor and the axonal transport proteins kinesin and dynein were substantially decreased in DP relative to NDC participants. Traumatic brain injury is a risk factor for dementia development, and our findings are consistent with permanent structural and functional damage in the cerebral cortex and white matter of boxers. Understanding the precise threshold of damage needed for the induction of pathology in DP and TBI is vital.
Neurochemical Profile of Dementia Pugilistica
Kokjohn, Tyler A.; Maarouf, Chera L.; Daugs, Ian D.; Hunter, Jesse M.; Whiteside, Charisse M.; Malek-Ahmadi, Michael; Rodriguez, Emma; Kalback, Walter; Jacobson, Sandra A.; Sabbagh, Marwan N.; Beach, Thomas G.
2013-01-01
Abstract Dementia pugilistica (DP), a suite of neuropathological and cognitive function declines after chronic traumatic brain injury (TBI), is present in approximately 20% of retired boxers. Epidemiological studies indicate TBI is a risk factor for neurodegenerative disorders including Alzheimer disease (AD) and Parkinson disease (PD). Some biochemical alterations observed in AD and PD may be recapitulated in DP and other TBI persons. In this report, we investigate long-term biochemical changes in the brains of former boxers with neuropathologically confirmed DP. Our experiments revealed biochemical and cellular alterations in DP that are complementary to and extend information already provided by histological methods. ELISA and one-dimensional and two dimensional Western blot techniques revealed differential expression of select molecules between three patients with DP and three age-matched non-demented control (NDC) persons without a history of TBI. Structural changes such as disturbances in the expression and processing of glial fibrillary acidic protein, tau, and α-synuclein were evident. The levels of the Aβ–degrading enzyme neprilysin were reduced in the patients with DP. Amyloid-β levels were elevated in the DP participant with the concomitant diagnosis of AD. In addition, the levels of brain-derived neurotrophic factor and the axonal transport proteins kinesin and dynein were substantially decreased in DP relative to NDC participants. Traumatic brain injury is a risk factor for dementia development, and our findings are consistent with permanent structural and functional damage in the cerebral cortex and white matter of boxers. Understanding the precise threshold of damage needed for the induction of pathology in DP and TBI is vital. PMID:23268705
Metabolic network failures in Alzheimer’s disease: A biochemical road map
Toledo, Jon B.; Arnold, Matthias; Kastenmüuller, Gabi; Chang, Rui; Baillie, Rebecca A.; Han, Xianlin; Thambisetty, Madhav; Tenenbaum, Jessica D.; Suhre, Karsten; Thompson, J. Will; St. John-Williams, Lisa; MahmoudianDehkordi, Siamak; Rotroff, Daniel M.; Jack, John R.; Motsinger-Reif, Alison; Risacher, Shannon L.; Blach, Colette; Lucas, Joseph E.; Massaro, Tyler; Louie, Gregory; Zhu, Hongjie; Dallmann, Guido; Klavins, Kristaps; Koal, Therese; Kim, Sungeun; Nho, Kwangsik; Shen, Li; Casanova, Ramon; Varma, Sudhir; Legido-Quigley, Cristina; Moseley, M. Arthur; Zhu, Kuixi; Henrion, Marc Y. R.; van der Lee, Sven J.; Harms, Amy C.; Demirkan, Ayse; Hankemeier, Thomas; van Duijn, Cornelia M.; Trojanowski, John Q.; Shaw, Leslie M.; Saykin, Andrew J.; Weiner, Michael W.; Doraiswamy, P. Murali; Kaddurah-Daouk, Rima
2018-01-01
Introduction The Alzheimer’s Disease Research Summits of 2012 and 2015 incorporated experts from academia, industry, and nonprofit organizations to develop new research directions to transform our understanding of Alzheimer’s disease (AD) and propel the development of critically needed therapies. In response to their recommendations, big data at multiple levels are being generated and integrated to study network failures in disease. We used metabolomics as a global biochemical approach to identify peripheral metabolic changes in AD patients and correlate them to cerebrospinal fluid pathology markers, imaging features, and cognitive performance. Methods Fasting serum samples from the Alzheimer’s Disease Neuroimaging Initiative (199 control, 356 mild cognitive impairment, and 175 AD participants) were analyzed using the AbsoluteIDQ-p180 kit. Performance was validated in blinded replicates, and values were medication adjusted. Results Multivariable-adjusted analyses showed that sphingomyelins and ether-containing phosphatidylcholines were altered in preclinical biomarker-defined AD stages, whereas acylcarnitines and several amines, including the branched-chain amino acid valine and α-aminoadipic acid, changed in symptomatic stages. Several of the analytes showed consistent associations in the Rotterdam, Erasmus Rucphen Family, and Indiana Memory and Aging Studies. Partial correlation networks constructed for Aβ1–42, tau, imaging, and cognitive changes provided initial biochemical insights for disease-related processes. Coexpression networks interconnected key metabolic effectors of disease. Discussion Metabolomics identified key disease-related metabolic changes and disease-progression-related changes. Defining metabolic changes during AD disease trajectory and its relationship to clinical phenotypes provides a powerful roadmap for drug and biomarker discovery. PMID:28341160
The importance of biochemical and genetic findings in the diagnosis of atypical Norrie disease.
Rodríguez-Muñoz, Ana; García-García, Gema; Menor, Francisco; Millán, José M; Tomás-Vila, Miguel; Jaijo, Teresa
2018-01-26
Norrie disease (ND) is a rare X-linked disorder characterized by bilateral congenital blindness. ND is caused by a mutation in the Norrie disease pseudoglioma (NDP) gene, which encodes a 133-amino acid protein called norrin. Intragenic deletions including NDP and adjacent genes have been identified in ND patients with a more severe neurologic phenotype. We report the biochemical, molecular, clinical and radiological features of two unrelated affected males with a deletion including NDP and MAO genes. Biochemical and genetic analyses were performed to understand the atypical phenotype and radiological findings. Biogenic amines in cerebrospinal fluid (CSF) were measured by high-performance liquid chromatography. The coding exons of NDP gene were amplified by polymerase chain reaction. Multiplex ligation-dependent probe amplification and chromosomal microarray were carried out on both affected males. Computed tomography and magnetic resonance imaging were performed on the two patients. In one patient, the serotonin and catecholamine metabolite levels in CSF were virtually undetectable. In both patients, genetic studies revealed microdeletions in the Xp11.3 region, involving the NDP, MAOA and MAOB genes. Radiological examination demonstrated brain and cerebellar atrophy. We suggest that alterations caused by MAO deficit may remain during the first years of life. Clinical phenotype, biochemical findings and neuroimaging can guide the genetic study in patients with atypical ND and help us to a better understanding of this disease.
Forment, Josep V.; Jackson, Stephen P.
2016-01-01
Protein accumulation on chromatin has traditionally been studied using immunofluorescence microscopy or biochemical cellular fractionation followed by western immunoblot analysis. As a way to improve the reproducibility of this kind of analysis, make it easier to quantify and allow a stream-lined application in high-throughput screens, we recently combined a classical immunofluorescence microscopy detection technique with flow cytometry1. In addition to the features described above, and by combining it with detection of both DNA content and DNA replication, this method allows unequivocal and direct assignment of cell-cycle distribution of protein association to chromatin without the need for cell culture synchronization. Furthermore, it is relatively quick (no more than a working day from sample collection to quantification), requires less starting material compared to standard biochemical fractionation methods and overcomes the need for flat, adherent cell types that are required for immunofluorescence microscopy. PMID:26226461
Wang, Xun; Sun, Beibei; Liu, Boyang; Fu, Yaping; Zheng, Pan
2017-01-01
Experimental design focuses on describing or explaining the multifactorial interactions that are hypothesized to reflect the variation. The design introduces conditions that may directly affect the variation, where particular conditions are purposely selected for observation. Combinatorial design theory deals with the existence, construction and properties of systems of finite sets whose arrangements satisfy generalized concepts of balance and/or symmetry. In this work, borrowing the concept of "balance" in combinatorial design theory, a novel method for multifactorial bio-chemical experiments design is proposed, where balanced templates in combinational design are used to select the conditions for observation. Balanced experimental data that covers all the influencing factors of experiments can be obtianed for further processing, such as training set for machine learning models. Finally, a software based on the proposed method is developed for designing experiments with covering influencing factors a certain number of times.
Computational modelling of oxygenation processes in enzymes and biomimetic model complexes.
de Visser, Sam P; Quesne, Matthew G; Martin, Bodo; Comba, Peter; Ryde, Ulf
2014-01-11
With computational resources becoming more efficient and more powerful and at the same time cheaper, computational methods have become more and more popular for studies on biochemical and biomimetic systems. Although large efforts from the scientific community have gone into exploring the possibilities of computational methods for studies on large biochemical systems, such studies are not without pitfalls and often cannot be routinely done but require expert execution. In this review we summarize and highlight advances in computational methodology and its application to enzymatic and biomimetic model complexes. In particular, we emphasize on topical and state-of-the-art methodologies that are able to either reproduce experimental findings, e.g., spectroscopic parameters and rate constants, accurately or make predictions of short-lived intermediates and fast reaction processes in nature. Moreover, we give examples of processes where certain computational methods dramatically fail.
Mahalko, J R; Johnson, L K; Gallagher, S K; Milne, D B
1985-09-01
Dietary histories and seven-day food records were obtained for 54 apparently healthy older adults. The two dietary methods correlated for most nutrients, but mean differences were significant for several nutrients. Intakes below recommended levels occurred most frequently for energy, calcium, and zinc. Biochemical evidence of thiamin and riboflavin deficiency was unexpectedly frequent. Using food records, dietary iron correlated with serum ferritin. Using dietary histories, dietary protein correlated with serum albumin, and dietary zinc correlated with plasma zinc. Using either dietary method, plasma ascorbate was associated positively with both dietary ascorbate and ascorbate supplements, and negatively with cigarette smoking. Use of thiamin- or folate-containing supplements was associated with improved biochemical status for the respective vitamin. Though neither dietary histories nor food records give precise intake data for individuals, either method may be useful for epidemiologic studies with appropriate sample sizes.
Anastasiadi, Maria; Mohareb, Fady; Redfern, Sally P; Berry, Mark; Simmonds, Monique S J; Terry, Leon A
2017-07-05
The present study represents the first major attempt to characterize the biochemical profile in different tissues of a large selection of apple cultivars sourced from the United Kingdom's National Fruit Collection comprising dessert, ornamental, cider, and culinary apples. Furthermore, advanced machine learning methods were applied with the objective to identify whether the phenolic and sugar composition of an apple cultivar could be used as a biomarker fingerprint to differentiate between heritage and mainstream commercial cultivars as well as govern the separation among primary usage groups and harvest season. A prediction accuracy of >90% was achieved with the random forest method for all three models. The results highlighted the extraordinary phytochemical potency and unique profile of some heritage, cider, and ornamental apple cultivars, especially in comparison to more mainstream apple cultivars. Therefore, these findings could guide future cultivar selection on the basis of health-promoting phytochemical content.
Microscale Concentration Measurements Using Laser Light Scattering Methods
NASA Technical Reports Server (NTRS)
Niederhaus, Charles; Miller, Fletcher
2004-01-01
The development of lab-on-a-chip devices for microscale biochemical assays has led to the need for microscale concentration measurements of specific analyses. While fluorescence methods are the current choice, this method requires developing fluorophore-tagged conjugates for each analyte of interest. In addition, fluorescent imaging is also a volume-based method, and can be limiting as smaller detection regions are required.
Discrete stochastic simulation methods for chemically reacting systems.
Cao, Yang; Samuels, David C
2009-01-01
Discrete stochastic chemical kinetics describe the time evolution of a chemically reacting system by taking into account the fact that, in reality, chemical species are present with integer populations and exhibit some degree of randomness in their dynamical behavior. In recent years, with the development of new techniques to study biochemistry dynamics in a single cell, there are increasing studies using this approach to chemical kinetics in cellular systems, where the small copy number of some reactant species in the cell may lead to deviations from the predictions of the deterministic differential equations of classical chemical kinetics. This chapter reviews the fundamental theory related to stochastic chemical kinetics and several simulation methods based on that theory. We focus on nonstiff biochemical systems and the two most important discrete stochastic simulation methods: Gillespie's stochastic simulation algorithm (SSA) and the tau-leaping method. Different implementation strategies of these two methods are discussed. Then we recommend a relatively simple and efficient strategy that combines the strengths of the two methods: the hybrid SSA/tau-leaping method. The implementation details of the hybrid strategy are given here and a related software package is introduced. Finally, the hybrid method is applied to simple biochemical systems as a demonstration of its application.
[Nutritional status of adults with cystic fibrosis - current methods of assessment].
Szabla, Anna; Skorupa, Wojciech; Milewska, Magdalena; Weker, Halina
2015-11-01
Cystic fibrosis (CF) is one of the most frequent monogenic disease in the Caucasian population, inherited in an autosomal recessive pattern. This is a multiple organ disease and its main manifestations include pulmonary and gastrointestinal dysfunction. The exocrine pancreatic deficiency results in impaired digestion and absorption what may lead to malnutrition and vitamins and minerals deficiencies. The life expectancy of cystic fibrosis patients has been increasing over the past years, so there is a need to verify usefulness of existing or create new methods of nutritional status assessment. The aim of this paper was presentation current data on the methods of assessment and monitoring of nutritional status. Particular attention has been paid to appropriate nutritional support in prevention and treatment of malnutrition patients with cystic fibrosis. On the basis of recent literature we can conclude that the advanced nutritional status assessment is recommended in patient with CF by using anthropometrical methods, body composition analysis and biochemical data. Good nutritional status is connected with pulmonary functions, quality and life length. © 2015 MEDPRESS.
Czajkowski, R; Pérombelon, MCM; Jafra, S; Lojkowska, E; Potrykus, M; van der Wolf, JM; Sledz, W
2015-01-01
The soft rot Enterobacteriaceae (SRE) Pectobacterium and Dickeya species (formerly classified as pectinolytic Erwinia spp.) cause important diseases on potato and other arable and horticultural crops. They may affect the growing potato plant causing blackleg and are responsible for tuber soft rot in storage thereby reducing yield and quality. Efficient and cost-effective detection and identification methods are essential to investigate the ecology and pathogenesis of the SRE as well as in seed certification programmes. The aim of this review was to collect all existing information on methods available for SRE detection. The review reports on the sampling and preparation of plant material for testing and on over thirty methods to detect, identify and differentiate the soft rot and blackleg causing bacteria to species and subspecies level. These include methods based on biochemical characters, serology, molecular techniques which rely on DNA sequence amplification as well as several less-investigated ones. PMID:25684775
Popiela, A; Pańszczyk, M; Korzeniewski, J; Baranowski, W
2000-04-01
Clinical and biochemical parameters were analysed in 55 patients who underwent a caesarean section performed using Misgav Ladach method compared to reference group of 41 patients who underwent caesarean section using Pfannenstiel method. Shortened operation time, shortened hospitalisation time and less postoperative morbidity were observed in the Misgav Ladach group. This kind of method seems to have advantages in comparison to Pfannenstiel method.
The ONIOM molecular dynamics method for biochemical applications: cytidine deaminase
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matsubara, Toshiaki; Dupuis, Michel; Aida, Misako
2007-03-22
Abstract We derived and implemented the ONIOM-molecular dynamics (MD) method for biochemical applications. The implementation allows the characterization of the functions of the real enzymes taking account of their thermal motion. In this method, the direct MD is performed by calculating the ONIOM energy and gradients of the system on the fly. We describe the first application of this ONOM-MD method to cytidine deaminase. The environmental effects on the substrate in the active site are examined. The ONIOM-MD simulations show that the product uridine is strongly perturbed by the thermal motion of the environment and dissociates easily from the activemore » site. TM and MA were supported in part by grants from the Ministry of Education, Culture, Sports, Science and Technology of Japan. MD was supported by the Division of Chemical Sciences, Office of Basic Energy Sciences, and by the Office of Biological and Environmental Research of the U.S. Department of Energy DOE. Battelle operates Pacific Northwest National Laboratory for DOE.« less
Biochemical Reconstitution of the WAVE Regulatory Complex
Chen, Baoyu; Padrick, Shae B.; Henry, Lisa; Rosen, Michael K.
2014-01-01
The WAVE regulatory complex (WRC) is a 400-KDa heteropentameric protein assembly that plays a central role in controlling actin cytoskeletal dynamics in many cellular processes. The WRC acts by integrating diverse cellular cues and stimulating the actin nucleating activity of the Arp2/3 complex at membranes. Biochemical and biophysical studies of the underlying mechanisms of these processes require large amounts of purified WRC. Recent success in recombinant expression, reconstitution, purification and crystallization of the WRC has greatly advanced our understanding of the inhibition, activation and membrane recruitment mechanisms of this complex. But many important questions remain to be answered. Here we summarize and update the methods developed in our laboratory, which allow reliable and flexible production of tens of milligrams of recombinant WRC of crystallographic quality, sufficient for many biochemical and structural studies. PMID:24630101
Approximation and inference methods for stochastic biochemical kinetics—a tutorial review
NASA Astrophysics Data System (ADS)
Schnoerr, David; Sanguinetti, Guido; Grima, Ramon
2017-03-01
Stochastic fluctuations of molecule numbers are ubiquitous in biological systems. Important examples include gene expression and enzymatic processes in living cells. Such systems are typically modelled as chemical reaction networks whose dynamics are governed by the chemical master equation. Despite its simple structure, no analytic solutions to the chemical master equation are known for most systems. Moreover, stochastic simulations are computationally expensive, making systematic analysis and statistical inference a challenging task. Consequently, significant effort has been spent in recent decades on the development of efficient approximation and inference methods. This article gives an introduction to basic modelling concepts as well as an overview of state of the art methods. First, we motivate and introduce deterministic and stochastic methods for modelling chemical networks, and give an overview of simulation and exact solution methods. Next, we discuss several approximation methods, including the chemical Langevin equation, the system size expansion, moment closure approximations, time-scale separation approximations and hybrid methods. We discuss their various properties and review recent advances and remaining challenges for these methods. We present a comparison of several of these methods by means of a numerical case study and highlight some of their respective advantages and disadvantages. Finally, we discuss the problem of inference from experimental data in the Bayesian framework and review recent methods developed the literature. In summary, this review gives a self-contained introduction to modelling, approximations and inference methods for stochastic chemical kinetics.
NASA Astrophysics Data System (ADS)
Kureljušić, J.; Rokvić, N.; Jezdimirović, N.; Kureljušić, B.; Pisinov, B.; Karabasil, N.
2017-09-01
Listeria is the genus of a bacteria found in soil and water and some animals, including poultry and cattle. It can be present in raw milk and food made from raw milk. It can also live in food processing plants and contaminate a variety of processed meats. Microscopically, Listeria species appear as small, Gram-positive rods, which are sometimes arranged in short chains. In direct smears, they can be coccoid, so they can be mistaken for streptococci. Longer cells can resemble corynebacteria. Flagella are produced at room temperature but not at 37°C. Haemolytic activity on blood agar has been used as a marker to distinguish Listeria monocytogenes among other Listeria species, but it is not an absolutely definitive criterion. Further biochemical characterization is necessary to distinguish between the different Listeria species. The objective of this study was to detect, isolate and identify Listeria monocytogenes from poultry meat. Within a period of six months from January to June 2017, a total of 15 samples were collected. Three samples were positive for the presence of Listeria monocytogenes. Biochemical and microbiological tests as well as PCR technique using specific primers were used to confirm L. Monocytogenes in the samples.
Sun, Xiaodian; Jin, Li; Xiong, Momiao
2008-01-01
It is system dynamics that determines the function of cells, tissues and organisms. To develop mathematical models and estimate their parameters are an essential issue for studying dynamic behaviors of biological systems which include metabolic networks, genetic regulatory networks and signal transduction pathways, under perturbation of external stimuli. In general, biological dynamic systems are partially observed. Therefore, a natural way to model dynamic biological systems is to employ nonlinear state-space equations. Although statistical methods for parameter estimation of linear models in biological dynamic systems have been developed intensively in the recent years, the estimation of both states and parameters of nonlinear dynamic systems remains a challenging task. In this report, we apply extended Kalman Filter (EKF) to the estimation of both states and parameters of nonlinear state-space models. To evaluate the performance of the EKF for parameter estimation, we apply the EKF to a simulation dataset and two real datasets: JAK-STAT signal transduction pathway and Ras/Raf/MEK/ERK signaling transduction pathways datasets. The preliminary results show that EKF can accurately estimate the parameters and predict states in nonlinear state-space equations for modeling dynamic biochemical networks. PMID:19018286
Gakh, Andrei A.; Sachleben, Richard A.; Bryan, Jeff C.
1997-11-01
The race to create smaller devices is fueling much of the research in electronics. The competition has intensified with the advent of microelectromechanical systems (MEMS), in which miniaturization is already reaching the dimensional limits imposed by physics of current lithographic techniques. Also, in the realm of biochemistry, evidence is accumulating that certain enzyme complexes are capable of very sophisticated modes of motion. Complex synergistic biochemical complexes driven by sophisticated biomechanical processes are quite common. Their biochemical functions are based on the interplay of mechanical and chemical processes, including allosteric effects. In addition, the complexity of this interplay far exceeds thatmore » of typical chemical reactions. Understanding the behavior of artificial molecular devices as well as complex natural molecular biomechanical systems is difficult. Fortunately, the problem can be successfully resolved by direct molecular engineering of simple molecular systems that can mimic desired mechanical or electronic devices. These molecular systems are called technomimetics (the name is derived, by analogy, from biomimetics). Several classes of molecular systems that can mimic mechanical, electronic, or other features of macroscopic devices have been successfully synthesized by conventional chemical methods during the past two decades. In this article we discuss only one class of such model devices: molecular gearing systems.« less
Xu, Li; Wu, Lin; Liu, Tingting; Xing, Wenrong; Cao, Xinsheng; Zhang, Shu; Su, Zongyi
2017-09-01
[Purpose] The aim of our study was to explore the changes in the blood of servicemen in sub-health conditions during a 21-day balneotherapy program. [Subjects and Methods] For this study, 129 servicemen in sub-health condition were recruited. The subjects were randomly divided into either the balneotherapy group (70) or the control group (59). Subjects in the balneotherapy group received whole-body immersion bath therapy in thermomineral water (30 min daily) for 21 days. Their blood samples were examined 1 day before and after balneotherapy. The parameters studied included mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), white blood cell (WBC), lactic acid (LAC), alanine aminotransferase (ALT), glucose (GLU), and triglycerides (TG) levels. [Results] After 21 days of balneotherapy, MCH levels and MCHC increased significantly and WBC counts increased significantly. LAC levels decreased significantly. ALT, GLU, and TG levels decreased significantly. In the control group, there were no statistical differences before and after tap water baths following the same procedure. [Conclusion] A 21-day balneotherapy program significantly improved blood cell counts and blood biochemical indexes and reduced ponogen levels in servicemen in sub-health condition.
Understanding Muscle Dysfunction in Chronic Fatigue Syndrome
Rutherford, Gina; Manning, Philip; Newton, Julia L.
2016-01-01
Introduction. Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a debilitating disorder of unknown aetiology, characterised by severe disabling fatigue in the absence of alternative diagnosis. Historically, there has been a tendency to draw psychological explanations for the origin of fatigue; however, this model is at odds with findings that fatigue and accompanying symptoms may be explained by central and peripheral pathophysiological mechanisms, including effects of the immune, oxidative, mitochondrial, and neuronal pathways. For example, patient descriptions of their fatigue regularly cite difficulty in maintaining muscle activity due to perceived lack of energy. This narrative review examined the literature for evidence of biochemical dysfunction in CFS/ME at the skeletal muscle level. Methods. Literature was examined following searches of PUB MED, MEDLINE, and Google Scholar, using key words such as CFS/ME, immune, autoimmune, mitochondria, muscle, and acidosis. Results. Studies show evidence for skeletal muscle biochemical abnormality in CFS/ME patients, particularly in relation to bioenergetic dysfunction. Discussion. Bioenergetic muscle dysfunction is evident in CFS/ME, with a tendency towards an overutilisation of the lactate dehydrogenase pathway following low-level exercise, in addition to slowed acid clearance after exercise. Potentially, these abnormalities may lead to the perception of severe fatigue in CFS/ME. PMID:26998359
Iwakura, Nobuhiro; Yokoyama, Takeshi; Quaglia, Fabio; Mitsuoka, Kaoru; Mio, Kazuhiro; Shigematsu, Hideki; Shirouzu, Mikako; Kaji, Akira; Kaji, Hideko
2017-01-01
A model Post-Termination Complex (PoTC) used for the discovery of Ribosome Recycling Factor (RRF) was purified and characterized by cryo-electron microscopic analysis and biochemical methods. We established that the model PoTC has mostly one tRNA, at the P/E or P/P position, together with one mRNA. The structural studies were supported by the biochemical measurement of bound tRNA and mRNA. Using this substrate, we establish that the release of tRNA, release of mRNA and splitting of ribosomal subunits occur during the recycling reaction. Order of these events is tRNA release first followed by mRNA release and splitting almost simultaneously. Moreover, we demonstrate that IF3 is not involved in any of the recycling reactions but simply prevents the re-association of split ribosomal subunits. Our finding demonstrates that the important function of RRF includes the release of mRNA, which is often missed by the use of a short ORF with the Shine-Dalgarno sequence near the termination site. PMID:28542628
Characterization of lactic acid bacteria from local cow´s milk kefir
NASA Astrophysics Data System (ADS)
Ismail, YS; Yulvizar, C.; Mazhitov, B.
2018-03-01
One of products from milk fermentation is kefir. It is made by adding kefir grains which are composed of lactic acid bacteria and yeast into milk. The lactic acid bacteria are a group of bacteria that produce antimicrobial substances and able to inhibit the growth of pathogenic bacteria. In this research, the lactic acid bacteria were isolated from Aceh local cow`s milk kefir to determine the genus of the isolates. The methods used in the characterization of lactic acid bacteria are colony morphology, cell morphology, and biochemical tests which includes a catalase test; 5%, 6.5%, and 10% salt endurance tests; 37°C and 14°C temperature endurance tests, SIM test, TSIA test, MR-VP test, and O/F test. Of the four isolates found from the cow’s milk kefir, two isolates were confirmed as lactic acid bacteria (isolates SK-1 and SK-4). Both isolates are Gram positive bacteria, and have negative catalase activity. From the observations of colony morphology, cell morphology, and biochemical tests, it was found that the genus of SK-1 is Lactobacillus and the genus of SK-4 is Enterococcus.
Talei, Daryush; Valdiani, Alireza; Puad, Mohd Abdullah
2013-01-01
Proteomic analysis of plants relies on high yields of pure protein. In plants, protein extraction and purification present a great challenge due to accumulation of a large amount of interfering substances, including polysaccharides, polyphenols, and secondary metabolites. Therefore, it is necessary to modify the extraction protocols. A study was conducted to compare four protein extraction and precipitation methods for proteomic analysis. The results showed significant differences in protein content among the four methods. The chloroform-trichloroacetic acid-acetone method using 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer provided the best results in terms of protein content, pellets, spot resolution, and intensity of unique spots detected. An overall of 83 qualitative or quantitative significant differential spots were found among the four methods. Based on the 2-DE gel map, the method is expected to benefit the development of high-level proteomic and biochemical studies of Andrographis paniculata, which may also be applied to other recalcitrant medicinal plant tissues. © 2013 International Union of Biochemistry and Molecular Biology, Inc.
Clinical experimental stress studies: methods and assessment.
Bali, Anjana; Jaggi, Amteshwar Singh
2015-01-01
Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Stress induction methods are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these methods are also important for the development of novel pharmacological agents for stress management. The well-described methods to induce stress in humans include the cold pressor test, Trier Social Stress Test, Montreal Imaging Stress Task, Maastricht Acute Stress Test, CO2 challenge test, Stroop test, Paced Auditory Serial Addition Task, noise stress, and Mannheim Multicomponent Stress Test. Stress assessment in humans is done by measuring biochemical markers such as cortisol, cortisol awakening response, dexamethasone suppression test, salivary α-amylase, plasma/urinary norepinephrine, norepinephrine spillover rate, and interleukins. Physiological and behavioral changes such as galvanic skin response, heart rate variability, pupil size, and muscle and/or skin sympathetic nerve activity (microneurography) and cardiovascular parameters such as heart rate, blood pressure, and self-reported anxiety are also monitored to assess stress response. This present review describes these commonly employed methods to induce stress in humans along with stress assessment methods.
Spectroscopic Methods of Remote Sensing for Vegetation Characterization
NASA Astrophysics Data System (ADS)
Kokaly, R. F.
2013-12-01
Imaging spectroscopy (IS), often referred to as hyperspectral remote sensing, is one of the latest innovations in a very long history of spectroscopy. Spectroscopic methods have been used for understanding the composition of the world around us, as well as, the solar system and distant parts of the universe. Continuous sampling of the electromagnetic spectrum in narrow bands is what separates IS from previous forms of remote sensing. Terrestrial imaging spectrometers often have hundreds of channels that cover the wavelength range of reflected solar radiation, including the visible, near-infrared (NIR), and shortwave infrared (SWIR) regions. In part due to the large number of channels, a wide variety of methods have been applied to extract information from IS data sets. These can be grouped into several broad classes, including: multi-channel indices, statistical procedures, full spectrum mixing models, and spectroscopic methods. Spectroscopic methods carry on the more than 150 year history of laboratory-based spectroscopy applied to material identification and characterization. Spectroscopic methods of IS relate the positions and shapes of spectral features resolved by airborne and spaceborne sensors to the biochemical and physical composition of vegetation in a pixel. The chlorophyll 680nm, water 980nm, water 1200nm, SWIR 1700nm, SWIR 2100nm, and SWIR 2300nm features have been the subject of study. Spectral feature analysis (SFA) involves isolating such an absorption feature using continuum removal (CR) and calculating descriptors of the feature, such as center position, depth, width, area, and asymmetry. SFA has been applied to quantify pigment and non-pigment biochemical concentrations in leaves, plants, and canopies. Spectral feature comparison (SFC) utilizes CR of features in each pixel's spectrum and linear regression with continuum-removed features in reference spectra in a library of known vegetation types to map vegetation species and communities. SFC has been applied to map the distributions of minerals in soils and rocks; however, its application to characterize vegetation cover has been less widespread than SFA. Using IS data and the USGS Processing Routines in IDL for Spectroscopic Measurements (PRISM; http://pubs.usgs.gov/of/2011/1155/), this talk will examine requirements for and limitations in applying SFA and SFC to characterize vegetation. A time series of Airborne Visible/InfraRed Imaging Spectrometer (AVIRIS) data collected in the marshes of Louisiana following the Deepwater Horizon oil spill will be used to examine the impact of varying leaf water content on the shapes of the SWIR 1700, 2100, and 2300 nm features and the implications of these changes on vegetation identification and biochemical estimation. The USGS collection of HyMap data over Afghanistan, the largest terrestrial coverage of IS data to date, will be used to demonstrate the characterization of vegetation in arid and semi-arid regions, in which chlorophyll absorption is often weak and soil and rock mineral absorption features overlap vegetation features. Hyperion data, overlapping the HyMap data, will be presented to illustrate the complications that arise when signal-to-noise is low. The benefits of and challenges to applying a spectroscopic remote sensing approach to imaging spectrometer data will be discussed.
Single-molecule detection: applications to ultrasensitive biochemical analysis
NASA Astrophysics Data System (ADS)
Castro, Alonso; Shera, E. Brooks
1995-06-01
Recent developments in laser-based detection of fluorescent molecules have made possible the implementation of very sensitive techniques for biochemical analysis. We present and discuss our experiments on the applications of our recently developed technique of single-molecule detection to the analysis of molecules of biological interest. These newly developed methods are capable of detecting and identifying biomolecules at the single-molecule level of sensitivity. In one case, identification is based on measuring fluorescence brightness from single molecules. In another, molecules are classified by determining their electrophoretic velocities.
Fornasaro, Stefano; Vicario, Annalisa; De Leo, Luigina; Bonifacio, Alois; Not, Tarcisio; Sergo, Valter
2018-05-14
Raman hyperspectral imaging is an emerging practice in biological and biomedical research for label free analysis of tissues and cells. Using this method, both spatial distribution and spectral information of analyzed samples can be obtained. The current study reports the first Raman microspectroscopic characterisation of colon tissues from patients with Coeliac Disease (CD). The aim was to assess if Raman imaging coupled with hyperspectral multivariate image analysis is capable of detecting the alterations in the biochemical composition of intestinal tissues associated with CD. The analytical approach was based on a multi-step methodology: duodenal biopsies from healthy and coeliac patients were measured and processed with Multivariate Curve Resolution Alternating Least Squares (MCR-ALS). Based on the distribution maps and the pure spectra of the image constituents obtained from MCR-ALS, interesting biochemical differences between healthy and coeliac patients has been derived. Noticeably, a reduced distribution of complex lipids in the pericryptic space, and a different distribution and abundance of proteins rich in beta-sheet structures was found in CD patients. The output of the MCR-ALS analysis was then used as a starting point for two clustering algorithms (k-means clustering and hierarchical clustering methods). Both methods converged with similar results providing precise segmentation over multiple Raman images of studied tissues.
Ferreira, Adriano Martison; Bonesso, Mariana Fávero; Mondelli, Alessandro Lia; da Cunha, Maria de Lourdes Ribeiro de Souza
2012-12-01
The emergence of Staphylococcus spp. not only as human pathogens, but also as reservoirs of antibiotic resistance determinants, requires the development of methods for their rapid and reliable identification in medically important samples. The aim of this study was to compare three phenotypic methods for the identification of Staphylococcus spp. isolated from patients with urinary tract infection using the PCR of the 16S-23S interspace region generating molecular weight patterns (ITR-PCR) as reference. All 57 S. saprophyticus studied were correctly identified using only the novobiocin disk. A rate of agreement of 98.0% was obtained for the simplified battery of biochemical tests in relation to ITR-PCR, whereas the Vitek I system and novobiocin disk showed 81.2% and 89.1% agreement, respectively. No other novobiocin-resistant non-S. saprophyticus strain was identified. Thus, the novobiocin disk is a feasible alternative for the identification of S. saprophyticus in urine samples in laboratories with limited resources. ITR-PCR and the simplified battery of biochemical tests were more reliable than the commercial systems currently available. This study confirms that automated systems are still unable to correctly differentiate CoNS species and that simple, reliable and inexpensive methods can be used for routine identification. Copyright © 2012 Elsevier B.V. All rights reserved.
Rhoden, D L; Hancock, G A; Miller, J M
1993-03-01
A numerical-code system for the reference identification of Staphylococcus species, Stomatococcus mucilaginosus, and Micrococcus species was established by using a selected panel of conventional biochemicals. Results from 824 cultures (289 eye isolate cultures, 147 reference strains, and 388 known control strains) were used to generate a list of 354 identification code numbers. Each six-digit code number was based on results from 18 conventional biochemical reactions. Seven milliliters of purple agar base with 1% sterile carbohydrate solution added was poured into 60-mm-diameter agar plates. All biochemical tests were inoculated with 1 drop of a heavy broth suspension, incubated at 35 degrees C, and read daily for 3 days. All reactions were read and interpreted by the method of Kloos et al. (G. A. Hebert, C. G. Crowder, G. A. Hancock, W. R. Jarvis, and C. Thornsberry, J. Clin. Microbiol. 26:1939-1949, 1988; W. E. Kloos and D. W. Lambe, Jr., P. 222-237, in A. Balows, W. J. Hansler, Jr., K. L. Herrmann, H. D. Isenberg, and H. J. Shadomy, ed., Manual of Clinical Microbiology, 5th ed., 1991). This modified reference identification method was 96 to 98% accurate and could have value in reference and public health laboratory settings.
Raman spectral signatures of cervical exfoliated cells from liquid-based cytology samples
NASA Astrophysics Data System (ADS)
Kearney, Padraig; Traynor, Damien; Bonnier, Franck; Lyng, Fiona M.; O'Leary, John J.; Martin, Cara M.
2017-10-01
It is widely accepted that cervical screening has significantly reduced the incidence of cervical cancer worldwide. The primary screening test for cervical cancer is the Papanicolaou (Pap) test, which has extremely variable specificity and sensitivity. There is an unmet clinical need for methods to aid clinicians in the early detection of cervical precancer. Raman spectroscopy is a label-free objective method that can provide a biochemical fingerprint of a given sample. Compared with studies on infrared spectroscopy, relatively few Raman spectroscopy studies have been carried out to date on cervical cytology. The aim of this study was to define the Raman spectral signatures of cervical exfoliated cells present in liquid-based cytology Pap test specimens and to compare the signature of high-grade dysplastic cells to each of the normal cell types. Raman spectra were recorded from single exfoliated cells and subjected to multivariate statistical analysis. The study demonstrated that Raman spectroscopy can identify biochemical signatures associated with the most common cell types seen in liquid-based cytology samples; superficial, intermediate, and parabasal cells. In addition, biochemical changes associated with high-grade dysplasia could be identified suggesting that Raman spectroscopy could be used to aid current cervical screening tests.
Label-free optical resonant sensors for biochemical applications
NASA Astrophysics Data System (ADS)
Ciminelli, Caterina; Campanella, Clarissa Martina; Dell'Olio, Francesco; Campanella, Carlo Edoardo; Armenise, Mario Nicola
2013-03-01
For a number of years, the scientific community has been paying growing attention to the monitoring and enhancement of public health and the quality of life through the detection of all dangerous agents for the human body, including gases, proteins, virus, and bacterial agents. When these agents are detected through label-free biochemical sensors, the molecules are not modified structurally or functionally by adding fluorescent or radioactive dyes. This work focuses on label-free optical ring resonator-based configurations suited for bio-chemical sensing, highlighting their physical aspects and specific applications. Resonant wavelength shift and the modal splitting occurring when the analyte interacts with microresonant structures are the two major physical aspects analyzed in this paper. Competitive optical platforms proposed in the literature are also illustrated together with their properties and performance.
Muley, Milind M; Thakare, Vishnu N; Patil, Rajesh R; Kshirsagar, Ajay D; Naik, Suresh R
2012-08-01
Comparative neuroprotective potential of silymarin, piracetam and protocatechuic acid ethyl ester (PCA) was evaluated in focal ischemic rats. Various pharmacological, biochemical (lipid peroxidation, reduced glutathione, catalase, nitrite content, brain water content) and behavioural (memory impairment, motor control, neurological score) including infarct size and histopathological alterations were evaluated. Silymarin (200mg/kg) and PCA treatment significantly improved behavioural, biochemical and histopathological changes, and reduced water content and infarct size. However, piracetam only improved behavioural and histopathological changes, reduced water content and infarct size. The findings indicate that silymarin exhibits neuroprotective activity better than PCA and piracetam in focal ischemia/reperfusion reflected by its better restoration of behavioural and antioxidant profile. Copyright © 2012 Elsevier Inc. All rights reserved.
Simone, G; Paradiso, A; Cirillo, R; Mangia, A; Rella, G; Wiesel, S; Petroni, S; De Benedictis, G; De Lena, M
1991-01-01
Recently, a method similar to ER.ICA has been proposed for the progesterone receptor (PgR) using two monoclonal antibodies, JZB39 and KD68, specific for human PgR and characterized by a molecular weight of 95 and 120 Kd, respectively. A series of 73 breast cancer patients was studied with regards to ER and PgR using both immunocytochemical (ICA) and biochemical (DCC) assays. Results showed no substantial differences between the two methods when considering common clinical-pathological parameters. Overall agreement between ICA and DCC methods was found: 79% for PgR and 78% for ER. A slight quantitative correlation was also observed between the "score values" of the ICA method and the Fmol content of ER and PgR using the Brave-Pearson test (r = 0.49 for PgR; r = 0.43 for ER). Specificity of PgR.ICA method was 77% for PgR and 72% for ER; sensitivity was 82% and 83%, respectively. The ICA method is a reliable technique to assess PgR presence as well as ER. Further studies are necessary to evaluate the prognostic role of nuclear PgR.
[Distribution of anaerobes in periodontal abscess and its resistance to antibiotics].
He, Jun-lin; Yu, Li-ying; Chen, Jia-zhen
2012-12-01
To isolate and culture the predominant anaerobes from the periodontal abscesses, and to test the antibiotic susceptibility and drug resistant genes of the strains. The isolated strains were identified by both API20A biochemical method and polymerase chain reaction (PCR) method. The antibiotic susceptibility test was performed by agar dilution method. The resistant genes of the drug-resistant strains obtained were screened by PCR. The anaerobes were detected in 48% (28/58) of the samples and Prevotella melaninogenica (Pm) was mostly identified in 43% (12/28). API20A biochemical method had 82% (23/28) agreement with the 16SrRNA method in identification rate. Anaerobes were resistant to metronidazole, clindamycin and cefmetazole. The erythromycin-resistant methylase genes F (ermF) gene was detected in three of eight clindamycin resistant strains. None of them was found coded on bacterial plasmids. However, no metronidazole resistant gene was detected on drug resistant strains. Pm was the predominant species dectected in the periodontal abscess of the patients. The antibiotic agents should be used based on the genotypes and general condition of the patients.
Blood gas and serum biochemical RIs for healthy newborn Murrah buffaloes (Bubalus bubalis).
Santana, André M; Silva, Daniela G; Clemente, Virna; Pizauro, Lucas J L; Bernardes, Priscila A; Santana, Clarissa H; Eckersall, Peter D; Fagliari, José J
2018-03-01
There is a lack of published work on RIs for newborn buffaloes. Establishing blood gas and serum biochemical RIs for newborn buffaloes is important for monitoring health. This study establishes blood gas and serum biochemical RIs of newborn buffaloes. Twenty-eight newborn buffaloes, 10-30 days old, were selected. Thirty blood biochemical variables were analyzed. The Anderson-Darling test was used to assess the normality of the distribution. The Dixon test and the Tukey test were used to identify outliers. The RI and 90% CI were determined using standard and robust methods and the Box-Cox transformation. A total of 30 RIs for healthy buffalo calves have been reported in this study. RIs for blood gas variables were reported for pH, partial pressure of oxygen (pO 2 ), partial pressure of carbon dioxide (pCO 2 ), saturation of O 2 (SO 2 ), bicarbonate (cHCO 3 - ), base excess (BE), total carbon dioxide (ctCO 2 ), and anion gap (AG). RIs for serum biochemical variables were reported for glucose (GLU), direct bilirubin (DB), total bilirubin (TB), AST, ALP, GGT, CK, LDH, creatinine (CREA), urea, cholesterol (CHOL), triglycerides (TG), Ca, P, Mg, Na, K, iCa, Cl, iron, total protein (TP), and albumin (ALB). This is the first reported study covering complete serum chemistry and blood gas RIs for healthy 1-month-old Murrah buffaloes. © 2018 American Society for Veterinary Clinical Pathology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Chien Peter; Weinberg, Vivian; Shinohara, Katsuto
Purpose: Evaluate efficacy and toxicity of salvage high-dose-rate brachytherapy (HDRB) for locally recurrent prostate cancer after definitive radiation therapy (RT). Methods and Materials: We retrospectively analyzed 52 consecutively accrued patients undergoing salvage HDRB between 1998 and 2009 for locally recurrent prostate cancer after previous definitive RT. After pathologic confirmation of locally recurrent disease, patients received 36 Gy in 6 fractions. Twenty-four patients received neoadjuvant hormonal therapy before salvage, and no patients received adjuvant hormonal therapy. Determination of biochemical failure after salvage HDRB was based on the Phoenix definition. Overall survival (OS) and bF distributions were calculated using the Kaplan-Meier method.more » Univariate analyses were performed to identify predictors of biochemical control. Acute and late genitourinary (GU) and gastrointestinal (GI) toxicities, based on Common Terminology Criteria for Adverse Events (version 4), were documented. Results: Median follow-up after salvage HDRB was 59.6 months. The 5-year OS estimate was 92% (95% confidence interval [CI]: 80%-97%) with median survival not yet reached. Five-year biochemical control after salvage was 51% (95% CI: 34%-66%). Median PSA nadir postsalvage was 0.1 (range: 0-7.2) reached at a median of 10.2 months after completing HDRB. As for complications, acute and late grade 3 GU toxicities were observed in only 2% and 2%, respectively. No grade 2 or higher acute GI events and 4% grade 2 GI late events were observed. On univariate analysis, disease-free interval after initial definitive RT (P=.07), percent of positive cores at the time of diagnosis (P=.08), interval from first recurrence to salvage HDRB (P=.09), and pre-HDRB prostate-specific antigen (P=.07) were each of borderline significance in predicting biochemical control after salvage HDRB. Conclusions: Prostate HDRB is an effective salvage modality with relatively few long-term toxicities. We provide potential predictors of biochemical control for prostate salvage HDRB.« less
Margeli, Alexandra; Mantzou, Emilia; Konsta, Maria; Loutradis, Dimitrios; Mastorakos, George; Papassotiriou, Ioannis; Klapa, Maria I.; Kanaka-Gantenbein, Christina; Chrousos, George P.
2014-01-01
Background There have been increasing indications about an epigenetically-based elevated predisposition of assisted reproductive technology (ART) offspring to insulin resistance, which can lead to an unfavorable cardio-metabolic profile in adult life. However, the relevant long-term systematic molecular studies are limited, especially for the IntraCytoplasmic Sperm Injection (ICSI) method, introduced in 1992. In this study, we carefully defined a group of 42 prepubertal ICSI and 42 naturally conceived (NC) children. We assessed differences in their metabolic profile based on biochemical measurements, while, for a subgroup, plasma metabolomic analysis was also performed, investigating any relevant insulin resistance indices. Methods & Results Auxological and biochemical parameters of 42 6.8±2.1 yrs old ICSI-conceived and 42 age-matched controls were measured. Significant differences between the groups were determined using univariate and multivariate statistics, indicating low urea and low-grade inflammation markers (YKL-40, hsCRP) and high triiodothyronine (T3) in ICSI-children compared to controls. Moreover, plasma metabolomic analysis carried out for a subgroup of 10 ICSI- and 10 NC girls using Gas Chromatography-Mass Spectrometry (GC-MS) indicated clear differences between the two groups, characterized by 36 metabolites linked to obesity, insulin resistance and metabolic syndrome. Notably, the distinction between the two girl subgroups was accentuated when both their biochemical and metabolomic measurements were employed. Conclusions The present study contributes a large auxological and biochemical dataset of a well-defined group of pre-pubertal ICSI-conceived subjects to the research of the ART effect to the offspring's health. Moreover, it is the first time that the relevant usefulness of metabolomics was investigated. The acquired results are consistent with early insulin resistance in ICSI-offspring, paving the way for further systematic investigations. These data support that metabolomics may unravel metabolic differences before they become clinically or biochemically evident, underlining its utility in the ART research. PMID:24728198
Cozzolino, Daniel
2015-03-30
Vibrational spectroscopy encompasses a number of techniques and methods including ultra-violet, visible, Fourier transform infrared or mid infrared, near infrared and Raman spectroscopy. The use and application of spectroscopy generates spectra containing hundreds of variables (absorbances at each wavenumbers or wavelengths), resulting in the production of large data sets representing the chemical and biochemical wine fingerprint. Multivariate data analysis techniques are then required to handle the large amount of data generated in order to interpret the spectra in a meaningful way in order to develop a specific application. This paper focuses on the developments of sample presentation and main sources of error when vibrational spectroscopy methods are applied in wine analysis. Recent and novel applications will be discussed as examples of these developments. © 2014 Society of Chemical Industry.
Utilizing Ion-Mobility Data to Estimate Molecular Masses
NASA Technical Reports Server (NTRS)
Duong, Tuan; Kanik, Isik
2008-01-01
A method is being developed for utilizing readings of an ion-mobility spectrometer (IMS) to estimate molecular masses of ions that have passed through the spectrometer. The method involves the use of (1) some feature-based descriptors of structures of molecules of interest and (2) reduced ion mobilities calculated from IMS readings as inputs to (3) a neural network. This development is part of a larger effort to enable the use of IMSs as relatively inexpensive, robust, lightweight instruments to identify, via molecular masses, individual compounds or groups of compounds (especially organic compounds) that may be present in specific environments or samples. Potential applications include detection of organic molecules as signs of life on remote planets, modeling and detection of biochemicals of interest in the pharmaceutical and agricultural industries, and detection of chemical and biological hazards in industrial, homeland-security, and industrial settings.
Addison, Christina L; Bouganim, Nathaniel; Hilton, John; Vandermeer, Lisa; Dent, Susan; Amir, Eitan; Hopkins, Sean; Kuchuk, Iryna; Segal, Roanne; Song, Xinni; Gertler, Stan; Mazzarello, Sasha; Dranitsaris, George; Ooi, Daylily; Pond, Gregory; Clemons, Mark
2014-04-01
The optimal frequency of intravenous (IV) bisphosphonate administration is unclear. We thus performed a study evaluating the effects of switching from 3-4 to 12 weekly therapy in patients with biochemically defined low-risk bone metastases. Patients with serum C-telopeptide (CTx) levels ≤600 ng/L after ≥3 months of 3-4 weekly IV pamidronate were switched to 12 weekly therapy for 48 weeks. Primary endpoint was the proportion of patients maintaining CTx levels in the lower-risk range. All endpoints (serum CTx and bone-specific alkaline phosphatase (BSAP), skeletal-related events (SREs) and self-reported pain) were measured at baseline, 6, 12, 24, 36 and 48 weeks. Treatment failure was defined as biochemical failure (CTx > 600 ng/L) or a SRE. Exploratory biomarkers including; serum TGF-β, activin-A, bone sialoprotein (BSP), procollagen type 1 N-terminal propeptide and urinary N-telopeptide (NTx) were assessed at baseline as predictors for failure to complete treatment. Seventy-one patients accrued and 43 (61 %) completed 48 weeks of de-escalated therapy. Reasons for failure to complete treatment included; biochemical failure (CTx > 600 ng/L) (n = 10, 14.1 %), on-study SRE (n = 9, 12.7 %), disease progression (n = 7, 9.9 % including death from disease [n = 1, 1.4 %]) or patient choice (n = 2, 2.8 %). Elevated baseline levels of CTx, BSAP, NTx and BSP were associated with treatment failure. The majority of patients in this biochemically defined low-risk population could switch from 3-4 weekly to 12 weekly bisphosphonate therapy with no effect on CTx levels or SREs during the 48 week study. Larger trials are required to assess the roles of biomarkers as predictors of adequacy of de-escalated therapy.
de Oliveira Machado, Evelyn; Lima, Carlos Henrique Azeredo; Ogino, Liana Lumi; Kasuki, Leandro; Gadelha, Mônica R
2016-08-01
Acromegaly is associated with significant morbidity and increased mortality, but has a variable severity phenotype. The presence of the exon 3-deleted isoform of the growth hormone receptor (d3-GHR) may influence the disease phenotype and treatment outcomes, including the frequency of biochemical discordance after medical treatment. The objective of this study was to analyze the influence of the d3-GHR isoform on clinical and biochemical characteristics and in the treatment outcomes of Brazilian multiethnic acromegaly patients. We retrospectively analyzed our acromegaly outpatient clinic databank and collected demographic, clinical, biochemical and treatment outcome data from those patients who agreed to participate in the study. A blood sample was collected from all patients, the DNA was extracted and the GHR isoforms were evaluated by PCR, with the full length (fl)-GHR represented by a 935-bp fragment and the d3-GHR represented by a 532-bp fragment. A total of 121 patients were included. Fifty-six patients (46.3 %) were full-length homozygous (fl/fl), 48 (39.7 %) were heterozygous (fl/d3) and 17 (14.0 %) were d3-GHR homozygous (d3/d3). There was no difference between patients homozygous for the fl isoform and those harboring at least one d3-GHR allele in the demographic, clinical and biochemical data or in the treatment outcomes, including somatostatin receptor ligands (SRL) monotherapy, combination therapy with SRL and cabergoline and pegvisomant treatment. There was also no difference between the groups for the frequency of GH and IGF-I discordance after medical treatment. GHR exon 3 genotyping appears to have no clinical significance, at least in Brazilian acromegaly patients.
Ploegh, Hidde L.
2012-01-01
The influenza virus uses the hemagglutinin (HA) and neuraminidase (NA) glycoproteins to interact with and infect host cells. While biochemical and microscopic methods allow examination of the early steps in flu infection, the genesis of progeny virions has been more difficult to follow, mainly because of difficulties inherent in fluorescent labeling of flu proteins in a manner compatible with live cell imaging. We here apply sortagging as a chemoenzymatic approach to label genetically modified but infectious flu and track the flu glycoproteins during the course of infection. This method cleanly distinguishes influenza glycoproteins from host glycoproteins and so can be used to assess the behavior of HA or NA biochemically and to observe the flu glycoproteins directly by live cell imaging. PMID:22457626
Ultrasensitive biochemical sensing device and method of sensing analytes
Pinchuk, Anatoliy
2017-06-06
Systems and methods biochemically sense a concentration of a ligand using a sensor having a substrate having a metallic nanoparticle array formed onto a surface of the substrate. A light source is incident on the surface. A matrix is deposited over the nanoparticle array and contains a protein adapted to binding the ligand. A detector detects s-polarized and p-polarized light from the reflective surface. Spacing of nanoparticles in the array and wavelength of light are selected such that plasmon resonance occurs with an isotropic point such that -s and -p polarizations of the incident light result in substantially identical surface Plasmon resonance, wherein binding of the ligand to the protein shifts the resonance such that differences between the -S and -P polarizations give in a signal indicative of presence of the ligand.
Learning Petri net models of non-linear gene interactions.
Mayo, Michael
2005-10-01
Understanding how an individual's genetic make-up influences their risk of disease is a problem of paramount importance. Although machine-learning techniques are able to uncover the relationships between genotype and disease, the problem of automatically building the best biochemical model or "explanation" of the relationship has received less attention. In this paper, I describe a method based on random hill climbing that automatically builds Petri net models of non-linear (or multi-factorial) disease-causing gene-gene interactions. Petri nets are a suitable formalism for this problem, because they are used to model concurrent, dynamic processes analogous to biochemical reaction networks. I show that this method is routinely able to identify perfect Petri net models for three disease-causing gene-gene interactions recently reported in the literature.
A Program of Nutritional Education in Schools Reduced the Prevalence of Iron Deficiency in Students
García-Casal, María Nieves; Landaeta-Jiménez, Maritza; Puche, Rafael; Leets, Irene; Carvajal, Zoila; Patiño, Elijú; Ibarra, Carlos
2011-01-01
The objective was to determine the prevalence of iron, folates and retinol deficiencies in school children and to evaluate the changes after an intervention of nutritional education. The project was developed in 17 schools. The sample included 1,301 children (678 males and 623 females). A subsample of 480 individuals, was randomly selected for drawing blood for biochemical determinations before and after the intervention of nutritional education, which included in each school: written pre and post-intervention tests, 6 workshops, 2 participative talks, 5 game activities, 1 cooking course and 1 recipe contest. Anthropometrical and biochemical determinations included weight, height, body-mass index, nutritional status, hematocrit, serum ferritin, retinol and folate concentrations. There was high prevalence of iron (25%), folates (75%) and vitamin A (43%) deficiencies in school children, with a low consumption of fruit and vegetables, high consumption of soft drinks and snacks and almost no physical activity. The nutritional education intervention produced a significant reduction in iron deficiency prevalence (25 to 14%), and showed no effect on vitamin A and folates deficiencies. There was a slight improvement in nutritional status. This study shows, through biochemical determinations, that nutritional education initiatives and programs have an impact improving nutritional health in school children. PMID:21547083
USDA-ARS?s Scientific Manuscript database
Arbuscular mycorrhizal fungi (AMF) are well-known plant symbionts which provide enhanced phosphorus uptake as well as other benefits to their host plants. Quantification of mycorrhizal biomass and root colonization has traditionally been performed by root staining and microscopic examination methods...
Babesia canis vogeli, Ehrlichia canis, and Anaplasma platys infection in a dog.
Al Izzi, Salah; Martin, Donald S; Chan, Roxanne Y Y; Leutenegger, Christian M
2013-12-01
A 12-month-old male neutered mixed breed dog was presented with a history of diarrhea, lethargy, emaciation, polydypsia, and sniffling. Physical examination findings included pale mucous membranes, increased heart and respiratory rates, and normal rectal temperature (38°C). Hematologic abnormalities included anemia and thrombocytopenia. Biochemical abnormalities included hypoalbuminemia, hyperbilirubinemia, and elevated ALP and ALT activities. A SNAP 4Dx test result was positive for Ehrlichia canis. Babesia canis vogeli organisms were found in the peripheral blood films, while morulae of E canis were not seen. Real-time polymerase chain reaction testing confirmed the presence of both B c vogeli and E canis organisms, and also was positive for Anaplasma platys infection. The dog recovered following treatment with doxycycline and imidocarb dipropionate, with normal hematology and biochemical profiles. © 2013 American Society for Veterinary Clinical Pathology.
Karaźniewicz-Łada, Marta; Główka, Anna
2016-01-01
Vitamins are an essential element of nutrition and thus contribute to human health. Vitamins catalyze many biochemical reactions and their lack or excess can cause health problems. Therefore, monitoring vitamin concentrations in plasma or other biological fluids may be useful in the diagnosis of various disorders as well as in the treatment process. Several chromatographic methods have been developed for the determination of these compounds in biological samples, including high-performance liquid chromatography with UV and fluorescence detection. Recently, high-performance liquid chromatography with tandem mass spectrometry methods have been widely used for the determination of vitamins in complex matrices because of their high sensitivity and selectivity. This method requires preconditioning of samples for analysis, including protein precipitation and/or various extraction techniques. The choice of method may depend on the desired cost, convenience, turnaround time, specificity, and accuracy of the information to be obtained. This article reviews the recently reported chromatographic methods used for determination of vitamins in biological fluids. Relevant papers published mostly during the last 5 years were identified by an extensive PubMed search using appropriate keywords. Particular attention was given to the preparation steps and extraction techniques. This report may be helpful in the selection of procedures that are appropriate for certain types of biological materials and analytes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Female nurses' burnout symptoms: No association with the Hypothalamic-pituitary-thyroid (HPT) axis.
Guo, Yufang; Lam, Louisa; Luo, Yuanhui; Plummer, Virginia; Cross, Wendy; Li, Hui; Yin, Yizhen; Zhang, Jingping
2017-03-01
Across the world, hospital nurses experience a high level of burnout. Exploring biochemical markers of burnout could help to understand physiological changes and may provide useful evidence for preventing burnout symptoms. The current study included 94 female nurses from one Chinese third-level hospital. The Maslach Burnout Inventory-General Survey (MBI-GS) was used to investigate burnout symptoms: emotional exhaustion, cynicism, reduced professional efficacy, as well as the burnout average. The HPT axis was tested by checking blood levels of thyroid-stimulating hormone (TSH), thyroxin (T 4 ) and triiodothyronine (T 3 ). Nonparametric tests showed that no significant difference in biochemical markers was found between the burnout and non-burnout groups. Spearman correlation analysis found that biochemical markers had no significant association with burnout symptoms, except weakly negative associations between reduced professional efficacy and blood pressure and heart rate. These findings show a rather poor correlation of the HPT axis on burnout symptoms. Expanding the biochemical index of the HPT axis, comparing well-defined samples and using longitudinal studies are recommended for further studies. Copyright © 2016 Elsevier Ltd. All rights reserved.
Optimal Cytoplasmic Transport in Viral Infections
D'Orsogna, Maria R.; Chou, Tom
2009-01-01
For many viruses, the ability to infect eukaryotic cells depends on their transport through the cytoplasm and across the nuclear membrane of the host cell. During this journey, viral contents are biochemically processed into complexes capable of both nuclear penetration and genomic integration. We develop a stochastic model of viral entry that incorporates all relevant aspects of transport, including convection along microtubules, biochemical conversion, degradation, and nuclear entry. Analysis of the nuclear infection probabilities in terms of the transport velocity, degradation, and biochemical conversion rates shows how certain values of key parameters can maximize the nuclear entry probability of the viral material. The existence of such “optimal” infection scenarios depends on the details of the biochemical conversion process and implies potentially counterintuitive effects in viral infection, suggesting new avenues for antiviral treatment. Such optimal parameter values provide a plausible transport-based explanation of the action of restriction factors and of experimentally observed optimal capsid stability. Finally, we propose a new interpretation of how genetic mutations unrelated to the mechanism of drug action may nonetheless confer novel types of overall drug resistance. PMID:20046829
Zuverza-Mena, Nubia; Martínez-Fernández, Domingo; Du, Wenchao; Hernandez-Viezcas, Jose A; Bonilla-Bird, Nestor; López-Moreno, Martha L; Komárek, Michael; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L
2017-01-01
Recent investigations show that carbon-based and metal-based engineered nanomaterials (ENMs), components of consumer goods and agricultural products, have the potential to build up in sediments and biosolid-amended agricultural soils. In addition, reports indicate that both carbon-based and metal-based ENMs affect plants differently at the physiological, biochemical, nutritional, and genetic levels. The toxicity threshold is species-dependent and responses to ENMs are driven by a series of factors including the nanomaterial characteristics and environmental conditions. Effects on the growth, physiological and biochemical traits, production and food quality, among others, have been reported. However, a complete understanding of the dynamics of interactions between plants and ENMs is not clear enough yet. This review presents recent publications on the physiological and biochemical effects that commercial carbon-based and metal-based ENMs have in terrestrial plants. This document focuses on crop plants because of their relevance in human nutrition and health. We have summarized the mechanisms of interaction between plants and ENMs as well as identified gaps in knowledge for future investigations. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Cesini, Laura; Siniscalchi, Agostina; Grammatico, Sara; Andriani, Alessandro; Fiorini, Alessia; De Rosa, Luca; Za, Tommaso; Rago, Angela; Caravita, Tommaso; Petrucci, Maria Teresa
2018-05-02
The aim of this study was to evaluate the addition of cyclophosphamide in relapsed-refractory multiple myeloma patients (RRMM) who experienced biochemical relapse or progression without CRAB, during treatment with lenalidomide and dexamethasone (Rd), to slow down the progression in active relapse. This analysis included 31 patients with RRMM treated with Rd who received cyclophosphamide (CRd) at biochemical relapse. The CRd regimen was continued until disease progression. The median number of CRd cycles administered was 8 (range: 1-35). A response was observed in 9 (29%) patients. After a median observation time of 11 months, the median overall survival (OS) from the beginning of CRd was 17.7 months. The median progression-free survival (PFS) from the beginning of CRd was 13.1 months. The addition of cyclophosphamide delays the progression in patients who present a biochemical relapse during Rd treatment. The response rate and the duration of PFS obtained with minimal toxicities and low costs induced us to setting up a randomized clinical trial. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Liu, Ye; Cheng, Daming; Lin, I-Hsin; Abbott, Nicholas L.; Jiang, Hongrui
2012-01-01
Although biochemical sensing using liquid crystals (LC) has been demonstrated, relatively little attention has been paid towards the fabrication of in situ-formed LC sensing devices. Herein, we demonstrate a highly reproducible method to create uniform LC thin film on treated substrates, as needed, for LC sensing. We use shear forces generated by the laminar flow of aqueous liquid within a microfluidic channel to create LC thin films stabilized within microfabricated structures. The orientational response of the LC thin films to targeted analytes in aqueous phases was transduced and amplified by the optical birefringence of the LC thin films. The biochemical sensing capability of our sensing devices was demonstrated through experiments employing two chemical systems: dodecyl trimethylammonium bromide (DTAB) dissolved in an aqueous solution, and the hydrolysis of phospholipids by the enzyme phospholipase A2 (PLA2). PMID:22842797
Saez-Rodriguez, Julio; Gayer, Stefan; Ginkel, Martin; Gilles, Ernst Dieter
2008-08-15
The modularity of biochemical networks in general, and signaling networks in particular, has been extensively studied over the past few years. It has been proposed to be a useful property to analyze signaling networks: by decomposing the network into subsystems, more manageable units are obtained that are easier to analyze. While many powerful algorithms are available to identify modules in protein interaction networks, less attention has been paid to signaling networks de.ned as chemical systems. Such a decomposition would be very useful as most quantitative models are de.ned using the latter, more detailed formalism. Here, we introduce a novel method to decompose biochemical networks into modules so that the bidirectional (retroactive) couplings among the modules are minimized. Our approach adapts a method to detect community structures, and applies it to the so-called retroactivity matrix that characterizes the couplings of the network. Only the structure of the network, e.g. in SBML format, is required. Furthermore, the modularized models can be loaded into ProMoT, a modeling tool which supports modular modeling. This allows visualization of the models, exploiting their modularity and easy generation of models of one or several modules for further analysis. The method is applied to several relevant cases, including an entangled model of the EGF-induced MAPK cascade and a comprehensive model of EGF signaling, demonstrating its ability to uncover meaningful modules. Our approach can thus help to analyze large networks, especially when little a priori knowledge on the structure of the network is available. The decomposition algorithms implemented in MATLAB (Mathworks, Inc.) are freely available upon request. ProMoT is freely available at http://www.mpi-magdeburg.mpg.de/projects/promot. Supplementary data are available at Bioinformatics online.
Seth, Rajeev; Murthy, Peela Sree Ramchandra; Sistla, Sujatha; Subramanian, Mahadevan; Tamilarasu, Kadhiravan
2017-09-01
Acute bacterial meningitis is one of the major causes of morbidity and mortality in children and geriatric population, especially in developing countries. Methods of identification are standard culture and other phenotypic tests in many resource poor settings. To use molecular methods for the improvement of aetiological diagnosis of acute pyogenic meningitis in patients. CSF samples of 125 patients were included for the study. Gram staining and culture were performed according to standard procedures. Antigen was detected using commercial latex agglutination test kit. Multiplex PCR was performed using previously published primers and protocols. Fischer's exact test was used for finding association between presence of the disease and clinical/biochemical parameters, considering two tailed p<0.05 as statistically significant. Sensitivity, specificity, positive and negative predictive values were calculated using Graphpad QuicCalc software. A total of 39 cases (31.2%) were confirmed to be of acute pyogenic meningitis based on biochemical methods. Only 10/39 was positive for the three organisms tested. Multiplex PCR was able to detect one additional isolate each of Streptococcus pneumoniae and Haemophilus influenzae type b. When compared with multiplex PCR as the gold standard, culture and latex agglutination tests had same sensitivity (80%), specificity (100%), PPV (100%) and NPV (97.8%), whereas Gram stain had poor sensitivity (40%) and good specificity (95.6%). Detection rates were higher in multiplex PCR for the two organisms Streptococcus pneumoniae and Haemophilus influenzae type b. Multiplex PCR was more sensitive than culture or antigen detection, and employing this assay can significantly increase the speed and accuracy of identification of the pathogen.
Wendt, Lynn M; Murphy, J Austin; Smith, William A; Robb, Thomas; Reed, David W; Ray, Allison E; Liang, Ling; He, Qian; Sun, Ning; Hoover, Amber N; Nguyen, Quang A
2018-01-01
Wet anaerobic storage of corn stover can provide a year-round supply of feedstock to biorefineries meanwhile serving an active management approach to reduce the risks associated with fire loss and microbial degradation. Wet logistics systems employ particle size reduction early in the supply chain through field-chopping which removes the dependency on drying corn stover prior to baling, expands the harvest window, and diminishes the biorefinery size reduction requirements. Over two harvest years, in-field forage chopping was capable of reducing over 60% of the corn stover to a particle size of 6 mm or less. Aerobic and anaerobic storage methods were evaluated for wet corn stover in 100 L laboratory reactors. Of the methods evaluated, traditional ensiling resulted in <6% total solid dry matter loss (DML), about five times less than the aerobic storage process and slightly less than half that of the anaerobic modified-Ritter pile method. To further demonstrate the effectiveness of the anaerobic storage, a field demonstration was completed with 272 dry tonnes of corn stover; DML averaged <5% after 6 months. Assessment of sugar release as a result of dilute acid or dilute alkaline pretreatment and subsequent enzymatic hydrolysis suggested that when anaerobic conditions were maintained in storage, sugar release was either similar to or greater than as-harvested material depending on the pretreatment chemistry used. This study demonstrates that wet logistics systems offer practical benefits for commercial corn stover supply, including particle size reduction during harvest, stability in storage, and compatibility with biochemical conversion of carbohydrates for biofuel production. Evaluation of the operational efficiencies and costs is suggested to quantify the potential benefits of a fully-wet biomass supply system to a commercial biorefinery.
Wendt, Lynn M.; Murphy, J. Austin; Smith, William A.; Robb, Thomas; Reed, David W.; Ray, Allison E.; Liang, Ling; He, Qian; Sun, Ning; Hoover, Amber N.; Nguyen, Quang A.
2018-01-01
Wet anaerobic storage of corn stover can provide a year-round supply of feedstock to biorefineries meanwhile serving an active management approach to reduce the risks associated with fire loss and microbial degradation. Wet logistics systems employ particle size reduction early in the supply chain through field-chopping which removes the dependency on drying corn stover prior to baling, expands the harvest window, and diminishes the biorefinery size reduction requirements. Over two harvest years, in-field forage chopping was capable of reducing over 60% of the corn stover to a particle size of 6 mm or less. Aerobic and anaerobic storage methods were evaluated for wet corn stover in 100 L laboratory reactors. Of the methods evaluated, traditional ensiling resulted in <6% total solid dry matter loss (DML), about five times less than the aerobic storage process and slightly less than half that of the anaerobic modified-Ritter pile method. To further demonstrate the effectiveness of the anaerobic storage, a field demonstration was completed with 272 dry tonnes of corn stover; DML averaged <5% after 6 months. Assessment of sugar release as a result of dilute acid or dilute alkaline pretreatment and subsequent enzymatic hydrolysis suggested that when anaerobic conditions were maintained in storage, sugar release was either similar to or greater than as-harvested material depending on the pretreatment chemistry used. This study demonstrates that wet logistics systems offer practical benefits for commercial corn stover supply, including particle size reduction during harvest, stability in storage, and compatibility with biochemical conversion of carbohydrates for biofuel production. Evaluation of the operational efficiencies and costs is suggested to quantify the potential benefits of a fully-wet biomass supply system to a commercial biorefinery. PMID:29632861
The emerging complexity of ubiquitin architecture.
Ohtake, Fumiaki; Tsuchiya, Hikaru
2017-02-01
Ubiquitylation is an essential post-translational modification (PTM) of proteins with diverse cellular functions. Polyubiquitin chains with different topologies have different cellular roles, and are referred to as a 'ubiquitin code'. Recent studies have begun to reveal that more complex ubiquitin architectures function as important signals in several biological pathways. These include PTMs of ubiquitin itself, such as acetylated ubiquitin and phospho-ubiquitin. Moreover, important roles for heterogeneous polyubiquitin chains, such as mixed or branched chains, have been reported, which significantly increase the diversity of the ubiquitin code. In this review, we describe mass spectrometry-based methods to characterize the ubiquitin signal. We also describe recent advances in our understanding of complex ubiquitin architectures, including our own findings concerning ubiquitin acetylation and branching within polyubiquitin chains. © The Authors 2016. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.
Han, Guan-gen; Ding, Gang-qiang; Li, Chao-lin; Li, Shuang; Chen, Ling-xuan
2006-11-01
To Study the health-related effects of PCBs pollution to women and children living near the dismantling factories of disused transformers. 49 couples which include a pair of preschool child(8 - 10 years old) and his/her mother were matched as the objects from the central junior school of F neighborhood where the study was progressing. Fasting Venous blood was collected from the objects, in which the content of PCBs (including 13 isomers) was determined by ultrasonic trace analyses methods as well as blood and urine were subjected to biochemical test while investigation by questionnaire and physical examination were also required. The mean content(G) of PCBs is 176ng/g lipid in the venous blood of the women and 192 ng/g lipid in that of the children. There are 6% of the females found blood pressure abnormality in the physical examination, while 28% of those were found urinary routine abnormality and 4% lymph node tumefaction. Among the children, 82% of them were suffered from caries, 6% were found lymph node tumefaction and 16% urinary abnormality. Both the results of the blood and urine biochemical analyses as well as the physical examination indicated the prevalent abnormal status of the women and children in the area. The accumulating concentration of the PCBs in blood suggested that the dismantling of the disused transformers had resulted in a noticeable negative effect to the local environment.
Wickner, Reed B.; Kryndushkin, Dmitry; Shewmaker, Frank; McGlinchey, Ryan; Edskes, Herman K.
2012-01-01
Summary Saccharomyces cerevisiae has been a useful model organism in such fields as the cell cycle, regulation of transcription, protein trafficking and cell biology, primarily because of its ease of genetic manipulation. This is no less so in the area of amyloid studies. The endogenous yeast amyloids described to date include prions, infectious proteins (Table 1), and some cell wall proteins (1). and amyloids of humans and a fungal prion have also been studied using the yeast system. Accordingly, the emphasis of this chapter will be on genetic, biochemical, cell biological and physical methods particularly useful in the study of yeast prions and other amyloids studied in yeast. We limit our description of these methods to those aspects which have been most useful in studying yeast prions, citing more detailed expositions in the literature. Volumes on yeast genetics methods (2–4), and on amyloids and prions (5, 6) are useful, and Masison has edited a volume of Methods on “Identification, analysis and characterization of fungal prions” which covers some of this territory (7). We also outline some useful physical methods, pointing the reader to more extensive and authoratative descriptions. PMID:22528100
Mohammadi, Samira; Esfahani, Bahram Nasr; Moghim, Sharareh; Mirhendi, Hossein; Zaniani, Fatemeh Riyahi; Safaei, Hajieh Ghasemian; Fazeli, Hossein; Salehi, Mahshid
2017-01-01
Background: Nontuberculous mycobacteria (NTM) are a group of opportunistic pathogens and these are widely dispersed in water and soil resources. Identification of mycobacteria isolates by conventional methods including biochemical tests, growth rates, colony pigmentation, and presence of acid-fast bacilli is widely used, but these methods are time-consuming, labor-intensive, and may sometimes remain inconclusive. Materials and Methods: The DNA was extracted from NTM cultures using CTAB, Chelex, Chelex + Nonidet P-40, FTA® Elute card, and boiling The quantity and quality of the DNA extracted via these methods were determined using UV-photometer at 260 and 280 nm, and polymerase chain reaction (PCR) amplification of the heat-shock protein 65 gene with serially diluted DNA samples. Results: The CTAB method showed more positive results at 1:10–1:100,000 at which the DNA amount was substantial. With the Chelex method of DNA extraction, PCR amplification was detected at 1:10 and 1:1000 dilutions. Conclusions: According to the electrophoresis results, the CTAB and Chelex DNA extraction methods were more successful in comparison with the others as regard producing suitable concentrations of DNA with the minimum use of PCR inhibitor. PMID:29279831
Quantitation of absorbed or deposited materials on a substrate that measures energy deposition
Grant, Patrick G.; Bakajin, Olgica; Vogel, John S.; Bench, Graham
2005-01-18
This invention provides a system and method for measuring an energy differential that correlates to quantitative measurement of an amount mass of an applied localized material. Such a system and method remains compatible with other methods of analysis, such as, for example, quantitating the elemental or isotopic content, identifying the material, or using the material in biochemical analysis.
Sun, Yu-Yo; Yang, Dianer; Kuan, Chia-Yi
2011-01-01
A simple method to quantify cerebral infarction has great value for mechanistic and therapeutic studies in experimental stroke research. Immersion staining of unfixed brain slices with 2,3,5-triphenyltetrazolium chloride (TTC) is a popular method to determine cerebral infarction in preclinical studies. However, it is often difficult to apply immersion TTC-labeling to severely injured or soft newborn brains in rodents. Here we report an in-vivo TTC perfusion-labeling method based on osmotic opening of blood-brain-barrier with mannitol-pretreatment. This new method delineates cortical infarction correlated with the boundary of morphological cell injury, differentiates the induction or subcellular redistribution of apoptosis-related factors between viable and damaged areas, and easily determines the size of cerebral infarction in both adult and newborn mice. Using this method, we confirmed that administration of lipopolysaccharide 72 h before hypoxia-ischemia increases the damage in neonatal mouse brains, in contrast to its effect of protective preconditioning in adults. These results demonstrate a fast and inexpensive method that simplifies the task of quantifying cerebral infarction in small or severely injured brains and assists biochemical analysis of experimental cerebral ischemia. PMID:21982741
Binder, Moritz; Zhang, Ben Y.; Hillman, David W.; Kohli, Rhea; Kohli, Tanvi; Lee, Adam; Kohli, Manish
2016-01-01
Treatment with abiraterone acetate and prednisone (AA/P) prolongs survival in metastatic castration-resistant prostate cancer (mCRPC) patients. We evaluated the genetic variation in CYP17A1 as predictive of response to AA/P. A prospective collection of germline DNA prior to AA/P initiation and follow-up of a mCRPC cohort was performed. Five common single-nucleotide polymorphisms (SNPs) in CYP17A1 identified using a haplotype-based tagging algorithm were genotyped. Clinical outcomes included biochemical response and time to biochemical progression on AA/P. Logistic regression was used to assess the association between tag SNPs and biochemical response. Proportional hazards regression was used to assess the association between tag SNPs and time to biochemical progression. Odds or hazard ratio per minor allele were estimated and p-values below 0.05 were considered statistically significant. Germline DNA was successfully genotyped for four tag SNPs in 87 patients. The median age was 73 years (54–90); the median prostate-specific antigen was 66 ng/dL (0.1–99.9). A single SNP, rs2486758, was associated with lower odds of experiencing a biochemical response (Odds ratio 0.22, 95% confidence interval 0.07–0.63, p = 0.005) and a shorter time to biochemical progression (Hazard ratio 2.23, 95% confidence interval 1.39–3.56, p < 0.001). This tag SNP located in the promoter region of CYP17A1 will need further validation as a predictive biomarker for AA/P therapy. PMID:27409606
CAP/ACMG proficiency testing for biochemical genetics laboratories: a summary of performance.
Oglesbee, Devin; Cowan, Tina M; Pasquali, Marzia; Wood, Timothy C; Weck, Karen E; Long, Thomas; Palomaki, Glenn E
2018-01-01
PurposeTesting for inborn errors of metabolism is performed by clinical laboratories worldwide, each utilizing laboratory-developed procedures. We sought to summarize performance in the College of American Pathologists' (CAP) proficiency testing (PT) program and identify opportunities for improving laboratory quality. When evaluating PT data, we focused on a subset of laboratories that have participated in at least one survey since 2010.MethodsAn analysis of laboratory performance (2004 to 2014) on the Biochemical Genetics PT Surveys, a program administered by CAP and the American College of Medical Genetics and Genomics. Analytical and interpretive performance was evaluated for four tests: amino acids, organic acids, acylcarnitines, and mucopolysaccharides.ResultsSince 2010, 150 laboratories have participated in at least one of four PT surveys. Analytic sensitivities ranged from 88.2 to 93.4%, while clinical sensitivities ranged from 82.4 to 91.0%. Performance was higher for US participants and for more recent challenges. Performance was lower for challenges with subtle findings or complex analytical patterns.ConclusionUS clinical biochemical genetics laboratory proficiency is satisfactory, with a minority of laboratories accounting for the majority of errors. Our findings underscore the complex nature of clinical biochemical genetics testing and highlight the necessity of continuous quality management.
Accurate atom-mapping computation for biochemical reactions.
Latendresse, Mario; Malerich, Jeremiah P; Travers, Mike; Karp, Peter D
2012-11-26
The complete atom mapping of a chemical reaction is a bijection of the reactant atoms to the product atoms that specifies the terminus of each reactant atom. Atom mapping of biochemical reactions is useful for many applications of systems biology, in particular for metabolic engineering where synthesizing new biochemical pathways has to take into account for the number of carbon atoms from a source compound that are conserved in the synthesis of a target compound. Rapid, accurate computation of the atom mapping(s) of a biochemical reaction remains elusive despite significant work on this topic. In particular, past researchers did not validate the accuracy of mapping algorithms. We introduce a new method for computing atom mappings called the minimum weighted edit-distance (MWED) metric. The metric is based on bond propensity to react and computes biochemically valid atom mappings for a large percentage of biochemical reactions. MWED models can be formulated efficiently as Mixed-Integer Linear Programs (MILPs). We have demonstrated this approach on 7501 reactions of the MetaCyc database for which 87% of the models could be solved in less than 10 s. For 2.1% of the reactions, we found multiple optimal atom mappings. We show that the error rate is 0.9% (22 reactions) by comparing these atom mappings to 2446 atom mappings of the manually curated Kyoto Encyclopedia of Genes and Genomes (KEGG) RPAIR database. To our knowledge, our computational atom-mapping approach is the most accurate and among the fastest published to date. The atom-mapping data will be available in the MetaCyc database later in 2012; the atom-mapping software will be available within the Pathway Tools software later in 2012.
Lü, F; Shao, L M; Bru, V; Godon, J J; He, P J
2009-02-01
To investigate the synergetic effect of pH and biochemical components on bacterial community structure during mesophilic anaerobic degradation of solid wastes with different origins, and under acidic or neutral conditions. The bacterial community in 16 samples of solid wastes with different biochemical compositions and origins was evaluated during mesophilic anaerobic degradation at acidic and neutral pH. Denaturing gradient gel electrophoresis (DGGE) and single-strand conformation polymorphism (SSCP) were used to compare the communities. Multivariate analysis of the DGGE and SSCP results revealed that most of the dominant microbes were dependent on the content of easily degradable carbohydrates in the samples. Furthermore, the dominant microbes were divided into two types, those that preferred an acid environment and those that preferred a neutral environment. A shift in pH was found to change their preference for medium substrates. Although most of the substrates with similar origin and biochemical composition had similar microbial diversity during fermentation, some microbes were found only in substrates with specific origins. For example, two microbes were only found in substrate that contained lignocellulose and animal protein without starch. These microbes were related to micro-organisms that are found in swine manure, as well as in other intestinal or oral niches. In addition, the distribution of fermentation products was less sensitive to the changes in pH and biochemical components than the microbial community. Bacterial diversity during anaerobic degradation of organic wastes was affected by both pH and biochemical components; however, pH exerted a greater effect. The results of this study reveal that control of pH may be an effective method to produce a stable bacterial community and relatively similar product distribution during anaerobic digestion of waste, regardless of variation in the waste feedstocks.
de la Torre, E; Tello, M; Mateu, E M; Torre, E
2005-11-01
Classical biotyping characterizes strains by creating biotype profiles that consider only positive and negative results for a predefined set of biochemical tests. This method allows Salmonella subspecies to be distinguished but does not allow serotypes and phage types to be distinguished. The objective of this study was to determine the relatedness of isolates belonging to distinct Salmonella enterica subsp. enterica serotypes by using a refined biotyping process that considers the kinetics at which biochemical reactions take place. Using a Vitek GNI+ card for the identification of gram-negative organisms, we determined the biochemical kinetic reactions (28 biochemical tests) of 135 Salmonella enterica subsp. enterica strains of pig origin collected in Spain from 1997 to 2002 (59 Salmonella serotype Typhimurium strains, 25 Salmonella serotype Typhimurium monophasic variant strains, 25 Salmonella serotype Anatum strains, 12 Salmonella serotype Tilburg strains, 7 Salmonella serotype Virchow strains, 6 Salmonella serotype Choleraesuis strains, and 1 Salmonella enterica serotype 4,5,12:-:- strain). The results were expressed as the colorimetric and turbidimetric changes (in percent) and were used to enhance the classical biotype profile by adding kinetic categories. A hierarchical cluster analysis was performed by using the enhanced profiles and resulted in 14 clusters. Six major clusters grouped 94% of all isolates with a similarity of > or =95% within any given cluster, and eight clusters contained a single isolate. The six major clusters grouped not only serotypes of the same type but also phenotypic serotype variations into individual clusters. This suggests that metabolic kinetic reaction data from the biochemical tests commonly used for classic Salmonella enterica subsp. enterica biotyping can possibly be used to determine the relatedness between isolates in an easy and timely manner.
Organic solvent pretreatment of lignocellulosic biomass for biofuels and biochemicals: A review.
Zhang, Ke; Pei, Zhijian; Wang, Donghai
2016-01-01
Lignocellulosic biomass represents the largest potential volume and lowest cost for biofuel and biochemical production. Pretreatment is an essential component of biomass conversion process, affecting a majority of downstream processes, including enzymatic hydrolysis, fermentation, and final product separation. Organic solvent pretreatment is recognized as an emerging way ahead because of its inherent advantages, such as the ability to fractionate lignocellulosic biomass into cellulose, lignin, and hemicellulose components with high purity, as well as easy solvent recovery and solvent reuse. Objectives of this review were to update and extend previous works on pretreatment of lignocellulosic biomass for biofuels and biochemicals using organic solvents, especially on ethanol, methanol, ethylene glycol, glycerol, acetic acid, and formic acid. Perspectives and recommendations were given to fully describe implementation of proper organic solvent pretreatment for future research. Copyright © 2015 Elsevier Ltd. All rights reserved.
Biochemical functionalization of peptide nanotubes with phage displayed peptides
NASA Astrophysics Data System (ADS)
Swaminathan, Swathi; Cui, Yue
2016-09-01
The development of a general approach for the biochemical functionalization of peptide nanotubes (PNTs) could open up existing opportunities in both fundamental studies as well as a variety of applications. PNTs are spontaneously assembled organic nanostructures made from peptides. Phage display has emerged as a powerful approach for identifying selective peptide binding motifs. Here, we demonstrate for the first time the biochemical functionalization of PNTs via peptides identified from a phage display peptide library. The phage-displayed peptides are shown to recognize PNTs. These advances further allow for the development of bifunctional peptides for the capture of bacteria and the self-assembly of silver particles onto PNTs. We anticipate that these results could provide significant opportunities for using PNTs in both fundamental studies and practical applications, including sensors and biosensors nanoelectronics, energy storage devices, drug delivery, and tissue engineering.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morris, W. James, E-mail: jmorris@bccancer.bc.ca; BC Cancer Agency–Vancouver Centre, Vancouver, British Columbia; Tyldesley, Scott
Purpose: To report the primary endpoint of biochemical progression-free survival (b-PFS) and secondary survival endpoints from ASCENDE-RT, a randomized trial comparing 2 methods of dose escalation for intermediate- and high-risk prostate cancer. Methods and Materials: ASCENDE-RT enrolled 398 men, with a median age of 68 years; 69% (n=276) had high-risk disease. After stratification by risk group, the subjects were randomized to a standard arm with 12 months of androgen deprivation therapy, pelvic irradiation to 46 Gy, followed by a dose-escalated external beam radiation therapy (DE-EBRT) boost to 78 Gy, or an experimental arm that substituted a low-dose-rate prostate brachytherapy (LDR-PB) boost. Of the 398more » trial subjects, 200 were assigned to DE-EBRT boost and 198 to LDR-PB boost. The median follow-up was 6.5 years. Results: In an intent-to-treat analysis, men randomized to DE-EBRT were twice as likely to experience biochemical failure (multivariable analysis [MVA] hazard ratio [HR] 2.04; P=.004). The 5-, 7-, and 9-year Kaplan-Meier b-PFS estimates were 89%, 86%, and 83% for the LDR-PB boost versus 84%, 75%, and 62% for the DE-EBRT boost (log-rank P<.001). The LDR-PB boost benefited both intermediate- and high-risk patients. Because the b-PFS curves for the treatment arms diverge sharply after 4 years, the relative advantage of the LDR-PB should increase with longer follow-up. On MVA, the only variables correlated with reduced overall survival were age (MVA HR 1.06/y; P=.004) and biochemical failure (MVA HR 6.30; P<.001). Although biochemical failure was associated with increased mortality and randomization to DE-EBRT doubled the rate of biochemical failure, no significant overall survival difference was observed between the treatment arms (MVA HR 1.13; P=.62). Conclusions: Compared with 78 Gy EBRT, men randomized to the LDR-PB boost were twice as likely to be free of biochemical failure at a median follow-up of 6.5 years.« less
Current Status on Biochemistry and Molecular Biology of Microbial Degradation of Nicotine
Gurusamy, Raman; Natarajan, Sakthivel
2013-01-01
Bioremediation is one of the most promising methods to clean up polluted environments using highly efficient potent microbes. Microbes with specific enzymes and biochemical pathways are capable of degrading the tobacco alkaloids including highly toxic heterocyclic compound, nicotine. After the metabolic conversion, these nicotinophilic microbes use nicotine as the sole carbon, nitrogen, and energy source for their growth. Various nicotine degradation pathways such as demethylation pathway in fungi, pyridine pathway in Gram-positive bacteria, pyrrolidine pathway, and variant of pyridine and pyrrolidine pathways in Gram-negative bacteria have been reported. In this review, we discussed the nicotine-degrading pathways of microbes and their enzymes and biotechnological applications of nicotine intermediate metabolites. PMID:24470788
Designing a 'neotissue' using the principles of biology, chemistry and engineering.
Nannaparaju, Madhusudhan; Oragui, Emeka; Khan, Wasim S
2012-01-01
The traditional methods of treating musculoskeletal injuries and disorders are not completely effective and have several limitations. Tissue engineering involves using the principles of biology, chemistry and engineering to design a 'neotissue' that augments a malfunctioning in vivo tissue. The main requirements for functional engineered tissue include reparative cellular components that proliferate on a scaffold grown within a bioreactor that provides specific biochemical and physical signals to regulate cell differentiation and tissue assembly. In this review we provide an overview of the biology of common musculoskeletal tissue and discuss their common pathologies. We also describe the commonly used stem cells, scaffolds and bioreactors and evaluate their role in issue engineering.
NASA Astrophysics Data System (ADS)
John, Kevin
2017-01-01
Targeted radiotherapy is an emerging discipline of cancer therapy that exploits the biochemical differences between normal cells and cancer cells to selectively deliver a lethal dose of radiation to cancer cells, while leaving healthy cells relatively unperturbed. A broad overview of targeted alpha therapy including isotope production methods, and associated isotope production facility needs, will be provided. A more general overview of the US Department of Energy Isotope Program's Tri-Lab (ORNL, BNL, LANL) Research Effort to Provide Accelerator-Produced 225Ac for Radiotherapy will also be presented focusing on the accelerator-production of 225Ac and final product isolation methodologies for medical applications.
Expression and Purification of Rat Glucose Transporter 1 in Pichia pastoris.
Venskutonytė, Raminta; Elbing, Karin; Lindkvist-Petersson, Karin
2018-01-01
Large amounts of pure and homogenous protein are a prerequisite for several biochemical and biophysical analyses, and in particular if aiming at resolving the three-dimensional protein structure. Here we describe the production of the rat glucose transporter 1 (GLUT1), a membrane protein facilitating the transport of glucose in cells. The protein is recombinantly expressed in the yeast Pichia pastoris. It is easily maintained and large-scale protein production in shaker flasks, as commonly performed in academic research laboratories, results in relatively high yields of membrane protein. The purification protocol describes all steps needed to obtain a pure and homogenous GLUT1 protein solution, including cell growth, membrane isolation, and chromatographic purification methods.
NASA Astrophysics Data System (ADS)
Utada, Andrew
2014-03-01
Biofilms are structured multi-cellular communities that are fundamental to the biology and ecology of bacteria. Parasitic bacterial biofilms can cause lethal infections and biofouling, but commensal bacterial biofilms, such as those found in the gut, can break down otherwise indigestible plant polysaccharides and allow us to enjoy vegetables. The first step in biofilm formation, adaptation to life on a surface, requires a working knowledge of low Reynolds number fluid physics, and the coordination of biochemical signaling, polysaccharide production, and molecular motility motors. These crucial early stages of biofilm formation are at present poorly understood. By adapting methods from soft matter physics, we dissect bacterial social behavior at the single cell level for several prototypical bacterial species, including Pseudomonas aeruginosa and Vibrio cholerae.
Cryptococcus laurentii diarrhea post hematopoietic stem cell transplant.
Bhat, Vivek; Vira, Hemant; Khattry, Navin; Toshniwal, Manoj
2017-04-01
We report the recent isolation of Cryptococcus laurentii from the feces of a patient with Hodgkin's lymphoma who underwent autologous hematopoietic stem cell transplant (HSCT). The organism was identified using microscopic morphology, cultural characteristics, and biochemical tests including sugar assimilation. Minimum inhibitory concentration of various antifungals was determined by microbroth dilution method. The recovery of pure culture of C. laurentii from stool culture, and the patient's response to treatment with voriconazole support its potential etiological role. To the best of our knowledge, we report the first case of diarrhea caused by C. laurentii in an HSCT recipient. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Hoza, Abubakar S; Mfinanga, Sayoki G S; Moser, Irmgard; König, Brigitte
2017-06-08
Pulmonary nocardiosis mimic pulmonary tuberculosis in most clinical and radiological manifestations. In Tanzania, where tuberculosis is one of the major public health threat clinical impact of nocardiosis as the cause of the human disease remains unknown. The objective of the present study was to isolate and identify Nocardia isolates recovered from TB suspects in Northeastern, Tanzania by using biochemical and molecular methods. The study involved 744 sputum samples collected from 372 TB suspects from four periphery diagnostic centers in Northeastern, Tanzania. Twenty patients were diagnosed as having presumptively Nocardia infections based on microscopic, cultural characteristics and biomèrieux ID 32C Yeast Identification system and confirmed using 16S rRNA and hsp65 gene specific primers for Nocardia species and sequencing. Biochemically, the majority of the isolates were N. asteroides (n = 8/20, 40%), N. brasiliensis (n = 4/20, 20%), N. farcinica (n = 3/20, 15%), N. nova (n = 1/20, 5%). Other aerobic actinomycetales included Streptomyces cyanescens (n = 2/20, 10%), Streptomyces griseus, Actinomadura madurae each (n = 1/20, 5%). Results of 16S rRNA and hsp65 sequencing were concordant in 15/17 (88. 2%) isolates and discordant in 2/17 (11.8%) isolates. Majority of the isolates belonged to N. cyriacigeorgica and N. farcinica, four (23.5%) each. Our findings suggest that Nocardia species may be an important cause of pulmonary nocardiosis that is underdiagnosed or ignored. This underscores needs to consider pulmonary nocardiosis as a differential diagnosis when there is a failure of anti-TB therapy and as a possible cause of human infections.
Chandrashekar, BS; Prabhakara, S; Mohan, T; Shabeer, D; Bhandare, Basavaraj; Nalini, M; Sharmila, PS; Meghana, DL; Reddy, Basanth Kumar; Hanumantha Rao, HM; Sahajananda, H; Anbazhagan, K
2018-01-01
OBJECTIVES: Rubia cordifolia L. (RC) is a well-known and highly valuable medicinal plant in the Ayurvedic system. The present study involves evaluating antioxidant and cardioprotective property of RC root extract. MATERIALS AND METHODS: The characterization of RC root extract was carried out using standard phytochemical and biochemical analysis. The functional groups were analyzed by Fourier transform infrared (FTIR) spectroscopy and phytotherapeutic compounds were identified using high-resolution mass spectrometry (HR-MS). Cardioprotective activity of RC root extract was investigated against cyclophosphamide (CP; 100 mg/kg, i.p)-induced cardiotoxicity in male albino Wistar rats. RC (100, 200, and 400 mg/kg, p.o) or silymarin (100 mg/kg, p.o) was administered immediately after CP on the 1st day and the next consecutive 10 days. Biochemical and histopathological analysis was performed to observe the cardioprotective effects of RC root extract. RESULTS: Phytochemical analysis revealed the presence of secondary metabolites that include alkaloids, flavonoids, saponins, and anthraquinones in RC root extract. FTIR analysis revealed the presence of several functional groups. Based on HR-MS analysis, eight major phytotherapeutic compounds were identified in methanol root extract of RC. Biochemical analysis in CP-induced rat model administered with RC extract revealed significantly enhanced levels of antioxidant markers such as superoxide dismutase, catalase, and glutathione S-transferase. Histopathological study showed that the rat model treated with the root extract had reduced the cardiac injury. CONCLUSION: Our results have shown that the RC extract contains various antioxidant compounds with cardioprotective effect. Treatment with RC root extract could significantly protect CP-induced rats from cardiac tissue injury by restoring the antioxidant markers. PMID:29861523