WorldWideScience

Sample records for human biological samples

  1. Determination of cadmium and lead in human biological samples by spectrometric techniques: a review.

    Science.gov (United States)

    Lemos, Valfredo Azevedo; de Carvalho, Anaildes Lago

    2010-12-01

    The analysis of human biological samples, such as blood, urine, nails, and hair, is generally used for the verification of human exposure to toxic metals. In this review, various spectrometric methods for the determination of cadmium and lead in biological samples are discussed and compared. Several spectrometric techniques are presented and discussed with respect to various characteristics such as sensitivity, selectivity, and cost. Special attention is drawn to the procedures for digestion prior to the determination of cadmium and lead in hair, nails, blood, and urine.

  2. Biological sample collector

    Science.gov (United States)

    Murphy, Gloria A.

    2010-09-07

    A biological sample collector is adapted to a collect several biological samples in a plurality of filter wells. A biological sample collector may comprise a manifold plate for mounting a filter plate thereon, the filter plate having a plurality of filter wells therein; a hollow slider for engaging and positioning a tube that slides therethrough; and a slide case within which the hollow slider travels to allow the tube to be aligned with a selected filter well of the plurality of filter wells, wherein when the tube is aligned with the selected filter well, the tube is pushed through the hollow slider and into the selected filter well to sealingly engage the selected filter well and to allow the tube to deposit a biological sample onto a filter in the bottom of the selected filter well. The biological sample collector may be portable.

  3. [Detection and typing by molecular biology of human papillomavirus in genital samples].

    Science.gov (United States)

    Suárez Moya, A; Esquivias Gómez, J I; Vidart Aragón, J A; Picazo de la Garza, J J

    2006-06-01

    Recently, there has been a marked increase in human papillomavirus (HPV) infection, and the etiological relationship between some HPV genotypes and genital cancer has been confirmed. Therefore, we used current molecular biology techniques to evaluate the prevalence of these viruses and their genotype in genital samples. We processed 401 genital samples from 281 women and 120 men, all with a diagnosis compatible with HPV infection. Virus was detected using PCR, and positive samples were typed using an array technique which enabled us to detect the 35 most common types of mucous-associated HPV. Of the 401 patients studied, 185 (46.1%) were positive, and only one type of HPV was detected in 133 cases. We found that 41.6% of the women and 56.7% of the men were positive. A total of 260 HPVs were typed; 154 were high oncogenic risk. They infected 16 men (23.5%) and 88 women (75.2%). The difference was statistically significant (pHVP 16 in 52 cases. We found a 46% prevalence of HPV infection. More than half of these patients were infected by high-risk HPV. The presence of high-risk HPV was significantly higher in women.

  4. Enhanced Biological Sampling Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of a variety of biological, reproductive, and energetic data collected from fish on the continental shelf in the northwest Atlantic Ocean. Species...

  5. Biological Sampling Variability Study

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-08

    There are many sources of variability that exist in the sample collection and analysis process. This paper addresses many, but not all, sources of variability. The main focus of this paper was to better understand and estimate variability due to differences between samplers. Variability between days was also studied, as well as random variability within each sampler. Experiments were performed using multiple surface materials (ceramic and stainless steel), multiple contaminant concentrations (10 spores and 100 spores), and with and without the presence of interfering material. All testing was done with sponge sticks using 10-inch by 10-inch coupons. Bacillus atrophaeus was used as the BA surrogate. Spores were deposited using wet deposition. Grime was coated on the coupons which were planned to include the interfering material (Section 3.3). Samples were prepared and analyzed at PNNL using CDC protocol (Section 3.4) and then cultured and counted. Five samplers were trained so that samples were taken using the same protocol. Each sampler randomly sampled eight coupons each day, four coupons with 10 spores deposited and four coupons with 100 spores deposited. Each day consisted of one material being tested. The clean samples (no interfering materials) were run first, followed by the dirty samples (coated with interfering material). There was a significant difference in recovery efficiency between the coupons with 10 spores deposited (mean of 48.9%) and those with 100 spores deposited (mean of 59.8%). There was no general significant difference between the clean and dirty (containing interfering material) coupons or between the two surface materials; however, there was a significant interaction between concentration amount and presence of interfering material. The recovery efficiency was close to the same for coupons with 10 spores deposited, but for the coupons with 100 spores deposited, the recovery efficiency for the dirty samples was significantly larger (65

  6. Gay and Bisexual Men's Perceptions of the Donation and Use of Human Biological Samples for Research: A Qualitative Study.

    Directory of Open Access Journals (Sweden)

    Chris Patterson

    Full Text Available Human biological samples (biosamples are increasingly important in diagnosing, treating and measuring the prevalence of illnesses. For the gay and bisexual population, biosample research is particularly important for measuring the prevalence of human immunodeficiency virus (HIV. By determining people's understandings of, and attitudes towards, the donation and use of biosamples, researchers can design studies to maximise acceptability and participation. In this study we examine gay and bisexual men's attitudes towards donating biosamples for HIV research. Semi-structured telephone interviews were conducted with 46 gay and bisexual men aged between 18 and 63 recruited in commercial gay scene venues in two Scottish cities. Interview transcripts were analysed thematically using the framework approach. Most men interviewed seemed to have given little prior consideration to the issues. Participants were largely supportive of donating tissue for medical research purposes, and often favourable towards samples being stored, reused and shared. Support was often conditional, with common concerns related to: informed consent; the protection of anonymity and confidentiality; the right to withdraw from research; and ownership of samples. Many participants were in favour of the storage and reuse of samples, but expressed concerns related to data security and potential misuse of samples, particularly by commercial organisations. The sensitivity of tissue collection varied between tissue types and collection contexts. Blood, urine, semen and bowel tissue were commonly identified as sensitive, and donating saliva and as unlikely to cause discomfort. To our knowledge, this is the first in-depth study of gay and bisexual men's attitudes towards donating biosamples for HIV research. While most men in this study were supportive of donating tissue for research, some clear areas of concern were identified. We suggest that these minority concerns should be accounted

  7. Biological Sample Monitoring Database (BSMDBS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Biological Sample Monitoring Database System (BSMDBS) was developed for the Northeast Fisheries Regional Office and Science Center (NER/NEFSC) to record and...

  8. Inalienably Yours? The new case for an inalienable property right in human biological material: Empowerment of sample donors or a recipe for a tragic Anti-Commons?

    Directory of Open Access Journals (Sweden)

    Jasper A. Bovenberg

    2004-12-01

    Full Text Available Modern biomedical research into the genetic component of common diseases calls for broad access to existing and novel collections of samples of human biological material, aka Biobanks. Groups of donors of these samples, however, increasingly claim a property right in their samples. They perceive the recognition of a personal property right in their biological material as the best means to serve two goals: to secure ongoing control over their samples after donation and to underpin their claim for a share in the proceeds that the research on their samples may yield. Given the objective of ensuring ongoing control, this property right is claimed to be inalienable. Recognition of a personal property right in one’s biological material is problematic, especially where the requirement of inalienability seems at odds with the claim for a share of the profits. Yet, property rights in human biological material may be justified in a certain context, e.g. to enable subsets of patients to negotiate the terms and conditions of the research into their specific disorders. Biobanks, however, contain so many samples, which can be used for so many research purposes, that the unrestricted exercise of personal property rights by the sample donors will lead to a proliferation of rights. This proliferation is likely to deter or slow down both the creation of de novo Biobanks and the use of existing sample collections. Thus, recognising inalienable property rights in human biological material may lead to suboptimal use of these resources and create a classic ‘anticommons property’ scenario. It would also undermine the current trend to simplify existing informed consent requirements which aims to facilitate broad and previously unanticipated research on de novo and existing Biobanks. In addition, the tradition of altruistic participation in research and the notion that large-scale collections of human biological material are global public goods are arguments against

  9. Biological Sample Ambient Preservation (BioSAP) Device Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address NASA's need for alternative methods for ambient preservation of human biological samples collected during extended spaceflight and planetary operations,...

  10. [The ethical implications of conserving biological samples].

    Science.gov (United States)

    Tazzite, A; Roky, R; Avard, D

    2009-09-01

    The conservation and use of biological samples become more and more frequent all around the world. Biobanks of human body substances (blood, urine, DNA, tissues, cells, etc.), and personal data associated with them are created. They have a double character as they are collections of both human biological samples and personal data. In some cases, the gametes, reproductive tissues, embryos, foetal tissue after abortion or even specimens of dead donors are collected and conserved. Although biobanks raise hopes in both the development of new therapies, new drugs and their integration into clinical medicine, they also point to concerns related to ethical questions such as: the principles of information, the consent of the persons concerned, the confidentiality about the personal data, and in some cases discrimination and stigmatisation. Other ethical aspects could raise gradually as research advance. Research being carried out on human sample requires informed free consent from the person who should be able to consent. The donor must be sufficiently informed about the process of research, the purpose, benefits and the risks involved in participating in this research. In the case of persons unable to give consent such minors or persons with mental disabilities, special measures are undertaken. Once the consent was given, the right of withdrawal has been consistently supported by the various declarations and regulations, but some oppose this right for a number of reasons particularly in the case of research on the samples without risk of physical exposure. In this case the notion of human body integrity is different than in research involving therapeutic or clinical intervention. In the case of withdrawal of consent, the samples should be destroyed, but the anonymous results arising from them and their analysis are not affected. What is the case for future uses? Should the researcher obtain again the consent from the donor for a secondary use of the samples? This is a

  11. Evaluation of calcium, magnesium, potassium and sodium in biological samples of male human immunodeficiency virus patients with tuberculosis and diarrhea compared to healthy control subjects in Pakistan.

    Science.gov (United States)

    Afridi, Hassan Imran; Kazi, Tasneem Gul; Talpur, Farah Naz; Kazi, Naveed; Naeemullah, Faheem Shah; Arain, Sadaf Sadia; Brahman, Kapil Dev

    2013-01-01

    Electrolyte deficiency has been associated with an increased risk of human immunodeficiency virus type 1 (HIV-1) disease progression and mortality. This study examined the association between low electrolyte concentrations in blood and scalp hair and the presence of opportunistic infections in patients with acquired immune deficiency syndrome (AIDS). Sixty-two male HIV positive patients (HIV-1) from various cities in Pakistan were recruited to the study. These Patients were divided into two groups according to secondary infections (tuberculosis and high fever with diarrhea), and biological samples (scalp hair, serum, blood and urine) were collected from them. As a comparative control group, 120 healthy subjects (males) of the same age group (31 - 45 years), socio-economic status, localities and dietary habits were also included in the study. The elements in the biological samples were analyzed by flame atomic absorption spectrophotometry after microwave-assisted acid digestion. Validity and accuracy of the methodology were checked using certified reference materials (CRMs) and against values obtained by a conventional wet acid digestion method on the same CRMs. The results indicated significantly lower levels of calcium, potassium, magnesium and natrium in all analyzed biological samples (blood, serum and scalp hair) of male patients with Acquired Immune Deficiency Syndrome (AIDS) in comparison to healthy controls (p < 0.01), while the levels of these elements were found to be higher in urine samples of the AIDS patients than in those of the control group. These data offer guidance to clinicians and other professionals investigating the deficiency of electrolytes in biological samples (scalp hair, serum and blood) of AIDS patients in relation to healthy subjects.

  12. Sensitive and Rapid UHPLC-MS/MS for the Analysis of Tomato Phenolics in Human Biological Samples

    Directory of Open Access Journals (Sweden)

    Miriam Martínez-Huélamo

    2015-11-01

    Full Text Available An UHPLC-MS/MS method for the quantification of tomato phenolic metabolites in human fluids was optimized and validated, and then applied in a pilot dietary intervention study with healthy volunteers. A 5-fold gain in speed (3.5 min of total run; 7-fold increase in MS sensitivity and 2-fold greater efficiency (50% peak width reduction were observed when comparing the proposed method with the reference-quality HPLC-MS/MS system, whose assay performance has been previously documented. The UHPLC-MS/MS method led to an overall improvement in the limits of detection (LOD and quantification (LOQ for all the phenolic compounds studied. The recoveries ranged between 68% and 100% in urine and 61% and 100% in plasma. The accuracy; intra- and interday precision; and stability met with the acceptance criteria of the AOAC International norms. Due to the improvements in the analytical method; the total phenolic metabolites detected in plasma and urine in the pilot intervention study were 3 times higher than those detected by HPLC-MS/MS. Comparing with traditional methods; which require longer time of analysis; the methodology described is suitable for the analysis of phenolic compounds in a large number of plasma and urine samples in a reduced time frame.

  13. Applied research and development of neutron activation analysis - The study on human health and environment by neutron activation analysis of biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seung Yeon; Yoo, Jong Ik; Lee, Jae Kwang; Lee, Sung Jun; Lee, Sang Sun; Jeon, Ki Hong; Na, Kyung Won; Kang, Sang Hun [Yonsei University, Seoul (Korea)

    2000-04-01

    With the development of the precise quantitative analytical method for the analysis of trace elements in the various biological samples such as hair and food, evaluation in view of health and environment to the trace elements in various sources which can be introduced inside human body was done. The trace elemental distribution in Korean total diet and representative food stuff was identified first. With the project the elemental distributions in supplemental healthy food and Korean and Chinese origin oriental medicine were identified. The amount of trace elements ingested with the hair analysis of oriental medicine takers were also estimated. The amounts of trace elements inhaled with the analysis of foundry air, blood and hair of foundry workers were also estimated. The basic estimation method in view of health and environment with the neutron activation analysis of biological samples such as foods and hair was established with the result. Nationwide usage system of the NAA facility in Hanaro in many different and important areas of biological area can be initiated with the results. The output of the project can support public heath, environment, and medical research area. The results can be applied for the process of micronutrients enhanced health food production and for the health safety and health status enhancement with the additional necessary data expansion and the development of various evaluation technique. 19 refs., 7 figs., 23 tabs. (Author)

  14. Accelerator mass spectrometry of small biological samples.

    Science.gov (United States)

    Salehpour, Mehran; Forsgard, Niklas; Possnert, Göran

    2008-12-01

    Accelerator mass spectrometry (AMS) is an ultra-sensitive technique for isotopic ratio measurements. In the biomedical field, AMS can be used to measure femtomolar concentrations of labeled drugs in body fluids, with direct applications in early drug development such as Microdosing. Likewise, the regenerative properties of cells which are of fundamental significance in stem-cell research can be determined with an accuracy of a few years by AMS analysis of human DNA. However, AMS nominally requires about 1 mg of carbon per sample which is not always available when dealing with specific body substances such as localized, organ-specific DNA samples. Consequently, it is of analytical interest to develop methods for the routine analysis of small samples in the range of a few tens of microg. We have used a 5 MV Pelletron tandem accelerator to study small biological samples using AMS. Different methods are presented and compared. A (12)C-carrier sample preparation method is described which is potentially more sensitive and less susceptible to contamination than the standard procedures.

  15. Biological Environmental Sampling Technologies Assessment

    Science.gov (United States)

    2015-12-01

    with many identifier platforms, including PCR, immunoassay, LFI, other immunoassays, gene sequencing, culturing , flow cytometry, and many other...Aquila 1000 instrument. Figure 7. Q-linea Aquila 1000 instrument. Vendor: Q-linea AB; Uppsala, Sweden Phone: +46.0.18.444.36.10 Website...and methods: Polymerase Chain Reaction (PCR), immunoassay, gene sequencing, culturing , etc... There must be enough collected sample remaining after

  16. Sample preparation in biological mass spectrometry

    CERN Document Server

    Ivanov, Alexander R

    2011-01-01

    The aim of this book is to provide the researcher with important sample preparation strategies in a wide variety of analyte molecules, specimens, methods, and biological applications requiring mass spectrometric analysis as a detection end-point.

  17. Biological Databases for Human Research

    Institute of Scientific and Technical Information of China (English)

    Dong Zou; Lina Ma; Jun Yu; Zhang Zhang

    2015-01-01

    The completion of the Human Genome Project lays a foundation for systematically studying the human genome from evolutionary history to precision medicine against diseases. With the explosive growth of biological data, there is an increasing number of biological databases that have been developed in aid of human-related research. Here we present a collection of human-related biological databases and provide a mini-review by classifying them into different categories according to their data types. As human-related databases continue to grow not only in count but also in volume, challenges are ahead in big data storage, processing, exchange and curation.

  18. Biological Databases for Human Research

    Science.gov (United States)

    Zou, Dong; Ma, Lina; Yu, Jun; Zhang, Zhang

    2015-01-01

    The completion of the Human Genome Project lays a foundation for systematically studying the human genome from evolutionary history to precision medicine against diseases. With the explosive growth of biological data, there is an increasing number of biological databases that have been developed in aid of human-related research. Here we present a collection of human-related biological databases and provide a mini-review by classifying them into different categories according to their data types. As human-related databases continue to grow not only in count but also in volume, challenges are ahead in big data storage, processing, exchange and curation. PMID:25712261

  19. Fluorine ion transmission through thin biological samples

    Institute of Scientific and Technical Information of China (English)

    XueJian-Ming; WangYu-Gang; 等

    1998-01-01

    F2+ beam with 3MeV is used to irradiate thin biological samples(onion inner suface membrane and kidney bean coat)in the transmission measurement ,its current density is 400-800nA/cm2,Results show that the onion samples can be broken up quickly under ion irradiating;as to kidney bean samples,about 60% of the implanted ions penetrate the samples,most of them lose part of their eneregy,fewer ions are found to be able to transmit through the sample without energy loss.SEM experiments are carried out to study sample's damage induced by the ions irradiation.

  20. Social justice and research using human biological material: A ...

    African Journals Online (AJOL)

    commercial medical research that uses human biological material, such as blood samples or other ... and provide that a person from whose body human biological material is withdrawn for .... part of investigators and institutions. This could be ...

  1. Modular microfluidic system for biological sample preparation

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Klint A.; Mariella, Jr., Raymond P.; Bailey, Christopher G.; Ness, Kevin Dean

    2015-09-29

    A reconfigurable modular microfluidic system for preparation of a biological sample including a series of reconfigurable modules for automated sample preparation adapted to selectively include a) a microfluidic acoustic focusing filter module, b) a dielectrophoresis bacteria filter module, c) a dielectrophoresis virus filter module, d) an isotachophoresis nucleic acid filter module, e) a lyses module, and f) an isotachophoresis-based nucleic acid filter.

  2. Discovering biological progression underlying microarray samples.

    Directory of Open Access Journals (Sweden)

    Peng Qiu

    2011-04-01

    Full Text Available In biological systems that undergo processes such as differentiation, a clear concept of progression exists. We present a novel computational approach, called Sample Progression Discovery (SPD, to discover patterns of biological progression underlying microarray gene expression data. SPD assumes that individual samples of a microarray dataset are related by an unknown biological process (i.e., differentiation, development, cell cycle, disease progression, and that each sample represents one unknown point along the progression of that process. SPD aims to organize the samples in a manner that reveals the underlying progression and to simultaneously identify subsets of genes that are responsible for that progression. We demonstrate the performance of SPD on a variety of microarray datasets that were generated by sampling a biological process at different points along its progression, without providing SPD any information of the underlying process. When applied to a cell cycle time series microarray dataset, SPD was not provided any prior knowledge of samples' time order or of which genes are cell-cycle regulated, yet SPD recovered the correct time order and identified many genes that have been associated with the cell cycle. When applied to B-cell differentiation data, SPD recovered the correct order of stages of normal B-cell differentiation and the linkage between preB-ALL tumor cells with their cell origin preB. When applied to mouse embryonic stem cell differentiation data, SPD uncovered a landscape of ESC differentiation into various lineages and genes that represent both generic and lineage specific processes. When applied to a prostate cancer microarray dataset, SPD identified gene modules that reflect a progression consistent with disease stages. SPD may be best viewed as a novel tool for synthesizing biological hypotheses because it provides a likely biological progression underlying a microarray dataset and, perhaps more importantly, the

  3. Molecular detection of human noroviruses in influent and effluent samples from two biological sewage treatment plants in the region of Monastir, Tunisia.

    Science.gov (United States)

    Hassine-Zaafrane, Mouna; Sdiri-Loulizi, Khira; Kaplon, Jérôme; Ben Salem, Imen; Pothier, Pierre; Aouni, Mahjoub; Ambert-Balay, Katia

    2014-06-01

    Noroviruses (NoVs) are responsible for numerous cases of waterborne and foodborne gastroenteritis every year. They are released in the sewage and their detection in this environment can reflect the epidemiology of the viral strains circulating in the community. A three-year (2007-2010) survey was conducted in order to evaluate the presence of human NoVs using RT-PCR in 518 sewage samples collected at the entrance and exit of two biological sewage treatment plants located in Monastir region, Tunisia. In this study, we aimed to genetically characterize the most prevalent GI and GII NoV strains, in order to obtain a rough estimate of the efficacy of disinfection treatments and to compare the results with clinical data documented in the same area during the same period. This work confirms the wide circulation and the genetic diversity of NoVs in Tunisia and the widespread distribution of NoV variants in both raw and treated wastewater. Indeed, NoV was detected in 192 (37.1%) sewage samples, among them mixed infections with group A rotavirus were detected in 125 (65.1%) cases. The genotypes of the GI NoVs were GI.1, GI.2, GI.4, GI.5, and GI of unassigned genotype (GI.UA), and the genotypes of the GII NoVs were all GII.12. This study enhances the currently poor environmental virological data gathered in Tunisia, demonstrates the benefit of environmental surveillance as a tool to determine the epidemiology of NoVs circulating in a given community, and underlines the need for the design and support of similar long-term studies in our country, in order to compensate for the absence of a national surveillance system for gastroenteric viruses.

  4. Target and non-target screening strategies for organic contaminants, residues and illicit substances in food , environmental and human biological samples by UHPLC-QTOF-MS

    OpenAIRE

    Hernández Hernández, Félix; Díaz San Pedro, Ramón; Sancho Llopis, Juan Vicente; Ibáñez Martínez, María

    2012-01-01

    In this paper, we illustrate the potential of ultra-high performance liquid chromatography (UHPLC) coupled with hybrid quadrupole time-of-flight mass spectrometry (QTOF MS) for large scale screening of organic contaminants in different types of samples. Thanks to the full-spectrum acquisition at satisfactory sensitivity, it is feasible to apply both (post)-target and non-target approaches for the rapid qualitative screening of organic pollutants in food, biological and environmental samples. ...

  5. Atomic force microscopy of biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, Mitchel John [ORNL

    2010-01-01

    The ability to evaluate structural-functional relationships in real time has allowed scanning probe microscopy (SPM) to assume a prominent role in post genomic biological research. In this mini-review, we highlight the development of imaging and ancillary techniques that have allowed SPM to permeate many key areas of contemporary research. We begin by examining the invention of the scanning tunneling microscope (STM) by Binnig and Rohrer in 1982 and discuss how it served to team biologists with physicists to integrate high-resolution microscopy into biological science. We point to the problems of imaging nonconductive biological samples with the STM and relate how this led to the evolution of the atomic force microscope (AFM) developed by Binnig, Quate, and Gerber, in 1986. Commercialization in the late 1980s established SPM as a powerful research tool in the biological research community. Contact mode AFM imaging was soon complemented by the development of non-contact imaging modes. These non-contact modes eventually became the primary focus for further new applications including the development of fast scanning methods. The extreme sensitivity of the AFM cantilever was recognized and has been developed into applications for measuring forces required for indenting biological surfaces and breaking bonds between biomolecules. Further functional augmentation to the cantilever tip allowed development of new and emerging techniques including scanning ion-conductance microscopy (SICM), scanning electrochemical microscope (SECM), Kelvin force microscopy (KFM) and scanning near field ultrasonic holography (SNFUH).

  6. Atomic force microscopy of biological samples.

    Science.gov (United States)

    Allison, David P; Mortensen, Ninell P; Sullivan, Claretta J; Doktycz, Mitchel J

    2010-01-01

    The ability to evaluate structural-functional relationships in real time has allowed scanning probe microscopy (SPM) to assume a prominent role in post genomic biological research. In this mini-review, we highlight the development of imaging and ancillary techniques that have allowed SPM to permeate many key areas of contemporary research. We begin by examining the invention of the scanning tunneling microscope (STM) by Binnig and Rohrer in 1982 and discuss how it served to team biologists with physicists to integrate high-resolution microscopy into biological science. We point to the problems of imaging nonconductive biological samples with the STM and relate how this led to the evolution of the atomic force microscope (AFM) developed by Binnig, Quate, and Gerber, in 1986. Commercialization in the late 1980s established SPM as a powerful research tool in the biological research community. Contact mode AFM imaging was soon complemented by the development of non-contact imaging modes. These non-contact modes eventually became the primary focus for further new applications including the development of fast scanning methods. The extreme sensitivity of the AFM cantilever was recognized and has been developed into applications for measuring forces required for indenting biological surfaces and breaking bonds between biomolecules. Further functional augmentation to the cantilever tip allowed development of new and emerging techniques including scanning ion-conductance microscopy (SICM), scanning electrochemical microscope (SECM), Kelvin force microscopy (KFM) and scanning near field ultrasonic holography (SNFUH). © 2010 John Wiley & Sons, Inc.

  7. The application of ESEM to biological samples

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, J E; Donald, A M, E-mail: jem60@cam.ac.u [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 OHE (United Kingdom)

    2010-07-01

    The Environmental Scanning Electron Microscope (ESEM) differs from a conventional SEM in that a differential pumping system maintains a pressure of gas (typically H{sub 2}O) in the specimen chamber whilst the gun remains at high vacuum. Ionizing collisions between electrons and these gas molecules create positive ions which drift down onto the sample neutralising specimen charge. It is therefore possible to image insulating samples without the need for metallic coating. The presence of water vapour in the chamber also means that a high relative humidity can be maintained and samples can be imaged in a hydrated state without the need for dehydration and fixation. These features suggest that ESEM could be well suited to imaging biological samples undergoing natural biological processes. We present a proof of principle study on the closure of stomatal pores in Tradescantia andersonia leaf tissue. An imaging protocol is developed and the advantages and limitations of this technique are discussed. Images of Vicia fabaleaf tissue are also presented. Challenges include minimising beam damage and reconciling the need for an adequate physiological temperature and a low gas pressure favourable for imaging, with the thermodynamic constraints on achieving a high relative humidity.

  8. Biological markets explain human ultrasociality.

    Science.gov (United States)

    Sheskin, Mark; Lambert, Stéphane; Baumard, Nicolas

    2016-01-01

    The evidence Gowdy & Krall (G&K) provide is more consistent with a biological markets explanation of human ultrasociality than a group selection explanation. Specifically, large-scale societies provide a better biological market for cooperation than do small-scale societies, allowing individuals to increase their fitness. Importantly, many of the quality-of-life costs G&K discuss (e.g., patriarchy) are not fitness costs.

  9. Measurement of NO in biological samples.

    Science.gov (United States)

    Csonka, C; Páli, T; Bencsik, P; Görbe, A; Ferdinandy, P; Csont, T

    2015-03-01

    Although the physiological regulatory function of the gasotransmitter NO (a diatomic free radical) was discovered decades ago, NO is still in the frontline research in biomedicine. NO has been implicated in a variety of physiological and pathological processes; therefore, pharmacological modulation of NO levels in various tissues may have significant therapeutic value. NO is generated by NOS in most of cell types and by non-enzymatic reactions. Measurement of NO is technically difficult due to its rapid chemical reactions with a wide range of molecules, such as, for example, free radicals, metals, thiols, etc. Therefore, there are still several contradictory findings on the role of NO in different biological processes. In this review, we briefly discuss the major techniques suitable for measurement of NO (electron paramagnetic resonance, electrochemistry, fluorometry) and its derivatives in biological samples (nitrite/nitrate, NOS, cGMP, nitrosothiols) and discuss the advantages and disadvantages of each method. We conclude that to obtain a meaningful insight into the role of NO and NO modulator compounds in physiological or pathological processes, concomitant assessment of NO synthesis, NO content, as well as molecular targets and reaction products of NO is recommended.

  10. Using electron microscopy to calculate optical properties of biological samples.

    Science.gov (United States)

    Wu, Wenli; Radosevich, Andrew J; Eshein, Adam; Nguyen, The-Quyen; Yi, Ji; Cherkezyan, Lusik; Roy, Hemant K; Szleifer, Igal; Backman, Vadim

    2016-11-01

    The microscopic structural origins of optical properties in biological media are still not fully understood. Better understanding these origins can serve to improve the utility of existing techniques and facilitate the discovery of other novel techniques. We propose a novel analysis technique using electron microscopy (EM) to calculate optical properties of specific biological structures. This method is demonstrated with images of human epithelial colon cell nuclei. The spectrum of anisotropy factor g, the phase function and the shape factor D of the nuclei are calculated. The results show strong agreement with an independent study. This method provides a new way to extract the true phase function of biological samples and provides an independent validation for optical property measurement techniques.

  11. [Biological material sampling for atomic absorption analysis].

    Science.gov (United States)

    Makarenko, N P; Ganebnykh, E V

    2007-01-01

    The optimum conditions have been chosen for mineralization of biological material for the atomic absorption determination of toxic metals, by using a [Russian characters: see text]-01 laboratory furnace (Gefest) upon exposure to high temperature, pressure, and microwave field. The completeness of dissection of biological material by microwave mineralization is shown under the optimal conditions.

  12. Digital holography microscopy in 3D biologic samples analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ricardo, J O; Palacios, F; Palacios, G F; Sanchez, A [Department of Physics, University of Oriente (Cuba); Muramatsu, M [Department of General Physics, University of Sao Paulo - Sao Paulo (Brazil); Gesualdi, M [Engineering center, Models and Applied Social Science, UFABC - Sao Paulo (Brazil); Font, O [Department of Bio-ingeniering, University of Oriente - Santiago de Cuba (Cuba); Valin, J L [Mechanics Department, ISPJAE, Habana (Cuba); Escobedo, M; Herold, S [Department of Computation, University of Oriente (Cuba); Palacios, D F, E-mail: frpalaciosf@gmail.com [Department of Nuclear physics, University of Simon BolIva (Venezuela, Bolivarian Republic of)

    2011-01-01

    In this work it is used a setup for Digital Holography Microscopy (MHD) for 3D biologic samples reconstruction. The phase contrast image reconstruction is done by using the Double propagation Method. The system was calibrated and tested by using a micrometric scale and pure phase object respectively. It was simulated the human red blood cell (erythrocyte) and beginning from the simulated hologram the digital 3D phase image for erythrocytes it was calculated. Also there was obtained experimental holograms of human erythrocytes and its corresponding 3D phase images, being evident the correspondence qualitative and quantitative between these characteristics in the simulated erythrocyte and in the experimentally calculated by DHM in both cases.

  13. Human Biology teaching portfolio for education subject Biology

    OpenAIRE

    Hlasová, Zuzana

    2011-01-01

    The aim of the thesis is to create a teaching portfolio with special attention to the educational content of Human Biology. Instructional manuals are created for teaching natural science at primary school and are focused on selected systems in Biology of the human being, which are: muscle system, breathing system, circulation system, digest system, sensuous system, and a chapter about nourishment. Regarding the present?day School educational programmes the teachers themselves choose the year ...

  14. Marine Biology and Human Affairs

    Science.gov (United States)

    Russell, F. S.

    1976-01-01

    Marine biology has become an important area for study throughout the world. The author of this article discusses some of the important discoveries and fields of research in marine biology that are useful for mankind. Topics include food from the sea, fish farming, pesticides, pollution, and conservation. (MA)

  15. Culture, Urbanism and Changing Human Biology

    OpenAIRE

    Schell, L M

    2014-01-01

    Anthropologists have long known that human activity driven by culture changes the environment. This is apparent in the archaeological record and through the study of the modern environment. Perhaps the largest change since the paleolithic era is the organization of human populations in cities. New environments can reshape human biology through evolution as shown by the evolution of the hominid lineage. Evolution is not the only process capable of reshaping our biology. Some changes in our hum...

  16. Microbial synthetic biology for human therapeutics.

    Science.gov (United States)

    Jain, Aastha; Bhatia, Pooja; Chugh, Archana

    2012-06-01

    The emerging field of synthetic biology holds tremendous potential for developing novel drugs to treat various human conditions. The current study discusses the scope of synthetic biology for human therapeutics via microbial approach. In this context, synthetic biology aims at designing, engineering and building new microbial synthetic cells that do not pre-exist in nature as well as re-engineer existing microbes for synthesis of therapeutic products. It is expected that the construction of novel microbial genetic circuitry for human therapeutics will greatly benefit from the data generated by 'omics' approaches and multidisciplinary nature of synthetic biology. Development of novel antimicrobial drugs and vaccines by engineering microbial systems are a promising area of research in the field of synthetic biology for human theragnostics. Expression of plant based medicinal compounds in the microbial system using synthetic biology tools is another avenue dealt in the present study. Additionally, the study suggest that the traditional medicinal knowledge can do value addition for developing novel drugs in the microbial systems using synthetic biology tools. The presented work envisions the success of synthetic biology for human therapeutics via microbial approach in a holistic manner. Keeping this in view, various legal and socio-ethical concerns emerging from the use of synthetic biology via microbial approach such as patenting, biosafety and biosecurity issues have been touched upon in the later sections.

  17. Systems biology of human atherosclerosis.

    Science.gov (United States)

    Shalhoub, Joseph; Sikkel, Markus B; Davies, Kerry J; Vorkas, Panagiotis A; Want, Elizabeth J; Davies, Alun H

    2014-01-01

    Systems biology describes a holistic and integrative approach to understand physiology and pathology. The "omic" disciplines include genomics, transcriptomics, proteomics, and metabolic profiling (metabonomics and metabolomics). By adopting a stance, which is opposing (yet complimentary) to conventional research techniques, systems biology offers an overview by assessing the "net" biological effect imposed by a disease or nondisease state. There are a number of different organizational levels to be understood, from DNA to protein, metabolites, cells, organs and organisms, even beyond this to an organism's context. Systems biology relies on the existence of "nodes" and "edges." Nodes are the constituent part of the system being studied (eg, proteins in the proteome), while the edges are the way these constituents interact. In future, it will be increasingly important to collaborate, collating data from multiple studies to improve data sets, making them freely available and undertaking integrative analyses.

  18. On-line Ultrasound-Assisted Dispersive Micro-Solid-Phase Extraction Based on Amino Bimodal Mesoporous Silica Nanoparticles for the Preconcentration and Determination of Cadmium in Human Biological Samples.

    Science.gov (United States)

    Shirkhanloo, H; Falahnejad, M; Zavvar Mousavi, H

    2016-06-01

    On-line ultrasound-assisted dispersive micro-solid-phase extraction (USA-DμSPE) has been developed for preconcentration and separation of trace amounts of Cd(II) ions in 0.5 mL of human biological samples. In a syringe with a nylon membrane, new synthetic bulky amino bimodal mesoporous silica nanoparticles (NH2-UVM7) were dispersed as a nanoadsorbent in 5 mL of diluted serum sample (1:10), and after ultrasonic shaking, the liquid phase was separated from the solid phase. At the optimized pH, the chemical and physical adsorption of cadmium ions occurred, respectively, based on complexation with amine groups of UVM7 (Cd:NH2-UVM7) and silica nanoparticles. The analyte was then back-extracted from the sorbent with nitric acid solution (0.2 M), and its concentration was determined by electrothermal atomic absorption spectrometry (ETAAS). Under the optimized conditions, the linear range, limit of detection (LOD), and preconcentration factor (PF) were obtained as 0.01-0.56 μg L(-1), 0.002 μg L(-1), and 25, respectively. The adsorption capacity of NH2-UVM7 was found to be 108.6 mg g(-1) of cadmium. The validation of the methodology was performed by the human standard reference material (HSRM).

  19. Biological Fingerprinting of Herbal Samples by Means of Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Łukasz Cieśla

    2012-01-01

    Full Text Available Biological chromatographic fingerprinting is a relatively new concept in the quality control of herbal samples. Originally it has been developed with the application of HPLC, and recently herbal samples' biological profiles have been obtained by means of thin-layer chromatography (TLC. This paper summarizes the application of liquid chromatographic techniques for the purpose of biological fingerprint analysis (BFA of complex herbal samples. In case of biological TLC fingerprint, which is a relatively novel solution, perspectives of its further development are outlined in more detail. Apart from already published data, some novel results are also shown and briefly discussed. The paper aims at drawing scientists' attention to the unique solutions offered by biological fingerprint construction.

  20. Manipulation of biological samples using micro and nano techniques

    DEFF Research Database (Denmark)

    Castillo, Jaime; Dimaki, Maria; Svendsen, Winnie Edith

    2009-01-01

    The constant interest in handling, integrating and understanding biological systems of interest for the biomedical field, the pharmaceutical industry and the biomaterial researchers demand the use of techniques that allow the manipulation of biological samples causing minimal or no damage to thei...

  1. Micro and Nano Techniques for the Handling of Biological Samples

    DEFF Research Database (Denmark)

    Micro and Nano Techniques for the Handling of Biological Samples reviews the different techniques available to manipulate and integrate biological materials in a controlled manner, either by sliding them along a surface (2-D manipulation), or by gripping and moving them to a new position (3-D man...

  2. Micro and Nano Techniques for the Handling of Biological Samples

    DEFF Research Database (Denmark)

    Micro and Nano Techniques for the Handling of Biological Samples reviews the different techniques available to manipulate and integrate biological materials in a controlled manner, either by sliding them along a surface (2-D manipulation), or by gripping and moving them to a new position (3-D...

  3. The human biology of Jim Tanner.

    Science.gov (United States)

    Cameron, Noël

    2012-09-01

    In 1940, during his second year of medical training, Jim Tanner expressed the desire to work, 'where physiology, psychology and sociology meet'. His subsequent exposure to the breadth of an American medical education and to the social and economic environment of post-war Europe distilled his belief in the importance of viewing the human in a broad context. Following his visits to the American longitudinal growth studies in 1948. Jim's dreams of a broad scientific discipline that incorporated both the biology and ecology of the human were strengthened by an inspirational group of embryonic human biologists with whom he developed '… the new Human Biology …' from the '… Physical Anthropology of old…'. With Jo Weiner, Derek Roberts, Geoffrey Harrison, Arthur Mourant, Nigel Barnicot and Kenneth Oakley, Jim was to form the Society for the Study of Human Biology in 1958. The development of human biology over the next 50 years was shaped by the expertise and diversity of that group of visionary scientists who conceived the scientific discipline of 'human biology' in which biology, behaviour and social context define the human species.

  4. A Review of Biological Agent Sampling Methods and ...

    Science.gov (United States)

    Report This study was conducted to evaluate current sampling and analytical capabilities, from a time and resource perspective, for a large-scale biological contamination incident. The analysis will be useful for strategically directing future research investment.

  5. [Biological Advisory Subcommittee Sampling Methods : Results, Resolutions, and Correspondences : 2002

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document contains a variety of information concerning Biological Advisory Subcommittee sampling methods at the Rocky Mountain Arsenal Refuge in 2002. Multiple...

  6. Agriculture and Biology Teaching. Biology and Human Welfare.

    Science.gov (United States)

    Rao, A. N.; Pritchard, Alan J.

    This six-chapter document (part of a series on biology and human welfare) focuses on agriculture and the teaching of this subject area. Major topic areas considered in the first five chapters are: (1) the development of agriculture; (2) agricosystems (considering agriculture as an ecosystem, land utilization and soils, soils and food production,…

  7. Solid-phase microextraction for the analysis of biological samples

    NARCIS (Netherlands)

    Theodoridis, G; Koster, EHM; de Jong, GJ

    2000-01-01

    Solid-phase microextraction (SPME) has been introduced for the extraction of organic compounds from environmental samples. This relatively new extraction technique has now also gained a lot of interest in a broad field of analysis including food, biological and pharmaceutical samples. SPME has a num

  8. Procedures for cryogenic X-ray ptychographic imaging of biological samples

    Science.gov (United States)

    Yusuf, M.; Zhang, F.; Chen, B.; Bhartiya, A.; Cunnea, K.; Wagner, U.; Cacho-Nerin, F.; Schwenke, J.; Robinson, I. K.

    2017-01-01

    Biological sample-preparation procedures have been developed for imaging human chromosomes under cryogenic conditions. A new experimental setup, developed for imaging frozen samples using beamline I13 at Diamond Light Source, is described. This manuscript describes the equipment and experimental procedures as well as the authors’ first ptychographic reconstructions using X-rays.

  9. Procedures for cryogenic X-ray ptychographic imaging of biological samples.

    Science.gov (United States)

    Yusuf, M; Zhang, F; Chen, B; Bhartiya, A; Cunnea, K; Wagner, U; Cacho-Nerin, F; Schwenke, J; Robinson, I K

    2017-03-01

    Biological sample-preparation procedures have been developed for imaging human chromosomes under cryogenic conditions. A new experimental setup, developed for imaging frozen samples using beamline I13 at Diamond Light Source, is described. This manuscript describes the equipment and experimental procedures as well as the authors' first ptychographic reconstructions using X-rays.

  10. Procedures for cryogenic X-ray ptychographic imaging of biological samples

    Directory of Open Access Journals (Sweden)

    M. Yusuf

    2017-03-01

    Full Text Available Biological sample-preparation procedures have been developed for imaging human chromosomes under cryogenic conditions. A new experimental setup, developed for imaging frozen samples using beamline I13 at Diamond Light Source, is described. This manuscript describes the equipment and experimental procedures as well as the authors' first ptychographic reconstructions using X-rays.

  11. Using electron microscopy to calculate optical properties of biological samples

    OpenAIRE

    Wu, Wenli; Radosevich, Andrew J.; Eshein, Adam; Nguyen, The-Quyen; Yi, Ji; Cherkezyan, Lusik; Roy, Hemant K.; Szleifer, Igal; Backman, Vadim

    2016-01-01

    The microscopic structural origins of optical properties in biological media are still not fully understood. Better understanding these origins can serve to improve the utility of existing techniques and facilitate the discovery of other novel techniques. We propose a novel analysis technique using electron microscopy (EM) to calculate optical properties of specific biological structures. This method is demonstrated with images of human epithelial colon cell nuclei. The spectrum of anisotropy...

  12. Biological bases of human musicality.

    Science.gov (United States)

    Perrone-Capano, Carla; Volpicelli, Floriana; di Porzio, Umberto

    2017-01-20

    Music is a universal language, present in all human societies. It pervades the lives of most human beings and can recall memories and feelings of the past, can exert positive effects on our mood, can be strongly evocative and ignite intense emotions, and can establish or strengthen social bonds. In this review, we summarize the research and recent progress on the origins and neural substrates of human musicality as well as the changes in brain plasticity elicited by listening or performing music. Indeed, music improves performance in a number of cognitive tasks and may have beneficial effects on diseased brains. The emerging picture begins to unravel how and why particular brain circuits are affected by music. Numerous studies show that music affects emotions and mood, as it is strongly associated with the brain's reward system. We can therefore assume that an in-depth study of the relationship between music and the brain may help to shed light on how the mind works and how the emotions arise and may improve the methods of music-based rehabilitation for people with neurological disorders. However, many facets of the mind-music connection still remain to be explored and enlightened.

  13. Separation methods for taurine analysis in biological samples.

    Science.gov (United States)

    Mou, Shifen; Ding, Xiaojing; Liu, Yongjian

    2002-12-05

    Taurine plays an important role in a variety of physiological functions, pharmacological actions and pathological conditions. Many methods for taurine analysis, therefore, have been reported to monitor its levels in biological samples. This review discusses the following techniques: sample preparation; separation and determination methods including high-performance liquid chromatography, gas chromatography, ion chromatography, capillary electrophoresis and hyphenation procedures. It covers articles published between 1990 and 2001.

  14. Enhanced sampling techniques in molecular dynamics simulations of biological systems.

    Science.gov (United States)

    Bernardi, Rafael C; Melo, Marcelo C R; Schulten, Klaus

    2015-05-01

    Molecular dynamics has emerged as an important research methodology covering systems to the level of millions of atoms. However, insufficient sampling often limits its application. The limitation is due to rough energy landscapes, with many local minima separated by high-energy barriers, which govern the biomolecular motion. In the past few decades methods have been developed that address the sampling problem, such as replica-exchange molecular dynamics, metadynamics and simulated annealing. Here we present an overview over theses sampling methods in an attempt to shed light on which should be selected depending on the type of system property studied. Enhanced sampling methods have been employed for a broad range of biological systems and the choice of a suitable method is connected to biological and physical characteristics of the system, in particular system size. While metadynamics and replica-exchange molecular dynamics are the most adopted sampling methods to study biomolecular dynamics, simulated annealing is well suited to characterize very flexible systems. The use of annealing methods for a long time was restricted to simulation of small proteins; however, a variant of the method, generalized simulated annealing, can be employed at a relatively low computational cost to large macromolecular complexes. Molecular dynamics trajectories frequently do not reach all relevant conformational substates, for example those connected with biological function, a problem that can be addressed by employing enhanced sampling algorithms. This article is part of a Special Issue entitled Recent developments of molecular dynamics. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Fast x-ray fluorescence microtomography of hydrated biological samples.

    Directory of Open Access Journals (Sweden)

    Enzo Lombi

    Full Text Available Metals and metalloids play a key role in plant and other biological systems as some of them are essential to living organisms and all can be toxic at high concentrations. It is therefore important to understand how they are accumulated, complexed and transported within plants. In situ imaging of metal distribution at physiological relevant concentrations in highly hydrated biological systems is technically challenging. In the case of roots, this is mainly due to the possibility of artifacts arising during sample preparation such as cross sectioning. Synchrotron x-ray fluorescence microtomography has been used to obtain virtual cross sections of elemental distributions. However, traditionally this technique requires long data acquisition times. This has prohibited its application to highly hydrated biological samples which suffer both radiation damage and dehydration during extended analysis. However, recent advances in fast detectors coupled with powerful data acquisition approaches and suitable sample preparation methods can circumvent this problem. We demonstrate the heightened potential of this technique by imaging the distribution of nickel and zinc in hydrated plant roots. Although 3D tomography was still impeded by radiation damage, we successfully collected 2D tomograms of hydrated plant roots exposed to environmentally relevant metal concentrations for short periods of time. To our knowledge, this is the first published example of the possibilities offered by a new generation of fast fluorescence detectors to investigate metal and metalloid distribution in radiation-sensitive, biological samples.

  16. Stability of glufosfamide in phosphate buffers and in biological samples.

    Science.gov (United States)

    Sun, Yuming; Chen, Xiaoyan; Xu, Haiyan; Guan, Zhongmin; Zhong, Dafang

    2006-03-07

    Glufosfamide is a new, potential chemotherapeutic agent currently under investigation. Stability of glufosfamide was investigated in sodium phosphate buffers with different pH and temperature and in biological samples. Glufosfamide and isophosphamide mustard were quantified simultaneously using a liquid chromatography-ion trap mass spectrometric method; precision and accuracy were within 15% for each analyte. Glufosfamide was stable in neutral buffers, but decomposed to form isophosphoramide mustard under acidic and basic conditions, which was pH- and temperature-dependent. The stability of glufosfamide varied in different biological samples. Results indicated that glufosfamide was unstable in some biological samples, such as the small intestine, smooth muscles, pancreas and urine, especially in the small intestine homogenate, with a half-life of 1.1 h. But the pH (<8) and beta-glucosidase of the tissue homogenate was found to have negligible contribution to the degradation of glufosfamide. The enzymatic inhibition experiment with the specific inhibitor, saccharo-1,4-lactone, demonstrated that it was glucuronidase that resulted in the degradation of glufosfamide in small intestine homogenate. Methanol was recommended to be used to homogenize the tissue in an ice water bath, and the container for urine collection should also be maintained in an ice water bath, and all the biological samples collected should be preserved in frozen condition until analysis.

  17. Biological stoichiometry in human cancer.

    Directory of Open Access Journals (Sweden)

    James J Elser

    Full Text Available BACKGROUND: A growing tumor in the body can be considered a complex ecological and evolutionary system. A new eco-evolutionary hypothesis (the "Growth Rate Hypothesis", GRH proposes that tumors have elevated phosphorus (P demands due to increased allocation to P-rich nucleic acids, especially ribosomal RNA, to meet the protein synthesis demands of accelerated proliferation. METHODOLOGY/PRINCIPAL FINDINGS: We determined the elemental (C, N, P and nucleic acid contents of paired malignant and normal tissues from colon, lung, liver, or kidney for 121 patients. Consistent with the GRH, lung and colon tumors were significantly higher (by approximately two-fold in P content (fraction of dry weight and RNA content and lower in nitrogen (N:P ratio than paired normal tissue, and P in RNA contributed a significantly larger fraction of total biomass P in malignant relative to normal tissues. Furthermore, patient-specific differences for %P between malignant and normal tissues were positively correlated with such differences for %RNA, both for the overall data and within three of the four organ sites. However, significant differences in %P and %RNA between malignant and normal tissues were not seen in liver and kidney and, overall, RNA contributed only approximately 11% of total tissue P content. CONCLUSIONS/SIGNIFICANCE: Data for lung and colon tumors provide support for the GRH in human cancer. The two-fold amplification of P content in colon and lung tumors may set the stage for potential P-limitation of their proliferation, as such differences often do for rapidly growing biota in ecosystems. However, data for kidney and liver do not support the GRH. To account for these conflicting observations, we suggest that local environments in some organs select for neoplastic cells bearing mutations increasing cell division rate ("r-selected," as in colon and lung while conditions elsewhere may select for reduced mortality rate ("K-selected," as in liver and

  18. Biological Systems, Energy Sources, and Biology Teaching. Biology and Human Welfare.

    Science.gov (United States)

    Tribe, Michael; Pritchard, Alan J.

    This five-chapter document (part of a series on biology and human welfare) focuses on biological systems as energy sources and on the teaching of this subject area. Chapter 1 discusses various topics related to energy and ecology, including biomass, photosynthesis and world energy balances, energy flow through ecosystems, and others. Chapter 2…

  19. Study of β-NMR for Liquid Biological Samples

    CERN Document Server

    Beattie, Caitlin

    2017-01-01

    β-NMR is an exotic form of NMR spectroscopy that allows for the characterization of matter based on the anisotropic β-decay of radioactive probe nuclei. This has been shown to be an effective spectroscopic technique for many different compounds, but its use for liquid biological samples is relatively unexplored. The work at the VITO line of ISOLDE seeks to employ this technique to study such samples. Currently, preparations are being made for an experiment to characterize DNA G-quadruplexes and their interactions with stabilizing cations. More specifically, the work in which I engaged as a summer student focused on the experiment’s liquid handling system and the stability of the relevant biological samples under vacuum.

  20. Patenting humans: clones, chimeras, and biological artifacts.

    Science.gov (United States)

    Hurlbut, William B

    2005-01-01

    The momentum of advances in biology is evident in the history of patents on life forms. As we proceed forward with greater understanding and technological control of developmental biology there will be many new and challenging dilemmas related to patenting of human parts and partial trajectories of human development. These dilemmas are already evident in the current conflict over the moral status of the early human embryo. In this essay, recent evidence from embryological studies is considered and the unbroken continuity of organismal development initiated at fertilization is asserted as clear and reasonable grounds for moral standing. Within this frame of analysis, it is proposed that through a technique of Altered Nuclear Transfer, non-organismal entities might be created from which embryonic stem cells could be morally procured. Criteria for patenting of such non-organismal entities are considered.

  1. Amchitka Island, Alaska, Biological Monitoring Report 2011 Sampling Results

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-09-01

    The Long-Term Surveillance and Maintenance (LTS&M) Plan for the U.S. Department of Energy (DOE) Office of Legacy Management (LM) Amchitka Island sites describes how LM plans to conduct its mission to protect human health and the environment at the three nuclear test sites located on Amchitka Island, Alaska. Amchitka Island, near the western end of the Aleutian Islands, is approximately 1,340 miles west-southwest of Anchorage, Alaska. Amchitka is part of the Aleutian Island Unit of the Alaska Maritime National Wildlife Refuge, which is administered by the U.S. Fish and Wildlife Service (USFWS). Since World War II, Amchitka has been used by multiple U.S. government agencies for various military and research activities. From 1943 to 1950, it was used as a forward air base for the U.S. Armed Forces. During the middle 1960s and early 1970s, the U.S. Department of Defense (DOD) and the U.S. Atomic Energy Commission (AEC) used a portion of the island as a site for underground nuclear tests. During the late 1980s and early 1990s, the U.S. Navy constructed and operated a radar station on the island. Three underground nuclear tests were conducted on Amchitka Island. DOD, in conjunction with AEC, conducted the first nuclear test (named Long Shot) in 1965 to provide data that would improve the United States' capability of detecting underground nuclear explosions. The second nuclear test (Milrow) was a weapons-related test conducted by AEC in 1969 as a means to study the feasibility of detonating a much larger device. Cannikin, the third nuclear test on Amchitka, was a weapons-related test detonated on November 6, 1971. With the exception of small concentrations of tritium detected in surface water shortly after the Long Shot test, radioactive fission products from the tests remain in the subsurface at each test location As a continuation of the environmental monitoring that has taken place on Amchitka Island since before 1965, LM in the summer of 2011 collected biological

  2. Toxicological Analysis of Some Drugs of Abuse in Biological Samples

    Directory of Open Access Journals (Sweden)

    Anne Marie Ciobanu

    2015-10-01

    Full Text Available Consumption of drugs of abuse is a scourge of modern world. Abuse, drug addiction and their consequences are one of the major current problems of European society because of the significant repercussions in individual, family, social and economic level. In this context, toxicological analysis of the drugs of abuse in biological samples is a useful tool for: diagnosis of drug addiction, checking an auto-response, mandatory screening in some treatment programs, identification of a substance in the case of an overdose, determining compliance of the treatment. The present paper aims to address the needs of healthcare professionals involved in drugs addiction treatment through systematic presentation of information regarding their toxicological analysis. Basically, it is a tool that help you to select the suitable biological sample and the right collecting time, as well as the proper analysis technique, depending on the purpose of analysis, pharmacokinetic characteristics of the drugs of abuse, available equipment and staff expertise.

  3. Analytical methodologies for the determination of benzodiazepines in biological samples.

    Science.gov (United States)

    Persona, Karolina; Madej, Katarzyna; Knihnicki, Paweł; Piekoszewski, Wojciech

    2015-09-10

    Benzodiazepine drugs belong to important and most widely used medicaments. They demonstrate such therapeutic properties as anxiolytic, sedative, somnifacient, anticonvulsant, diastolic and muscle relaxant effects. However, despite the fact that benzodiazepines possess high therapeutic index and are considered to be relatively safe, their use can be dangerous when: (1) co-administered with alcohol, (2) co-administered with other medicaments like sedatives, antidepressants, neuroleptics or morphine like substances, (3) driving under their influence, (4) using benzodiazepines non-therapeutically as drugs of abuse or in drug-facilitated crimes. For these reasons benzodiazepines are still studied and determined in a variety of biological materials. In this article, sample preparation techniques which have been applied in analysis of benzodiazepine drugs in biological samples have been reviewed and presented. The next part of the article is focused on a review of analytical methods which have been employed for pharmacological, toxicological or forensic study of this group of drugs in the biological matrices. The review was preceded by a description of the physicochemical properties of the selected benzodiazepines and two, very often coexisting in the same analyzed samples, sedative-hypnotic drugs.

  4. Biological Inspiration in Human Centred Robotics

    Institute of Scientific and Technical Information of China (English)

    HU Huo-sheng; LIU Jin-dong; Calderon Carlos A

    2004-01-01

    Human centred robotics (HCR) concerns with the development of various kinds of intelligent systems and robots that will be used in environments coexisting with humans. These systems and robots will be interactive and useful assistants/companions for people in different ages, situations, activities and environments in order to improve the quality of life. This paper presents the autors' current research work toward the development of advanced theory and technologies for HCR applications, based on inspiration from biological systems. More specifically, both bio-mimetic system modelling and robot learning by imitation are discussed respectively, and some preliminary results are demonstrated.

  5. Preparation of Biological Samples Containing Metoprolol and Bisoprolol for Applying Methods for Quantitative Analysis

    Directory of Open Access Journals (Sweden)

    Corina Mahu Ştefania

    2015-12-01

    Full Text Available Arterial hypertension is a complex disease with many serious complications, representing a leading cause of mortality. Selective beta-blockers such as metoprolol and bisoprolol are frequently used in the management of hypertension. Numerous analytical methods have been developed for the determination of these substances in biological fluids, such as liquid chromatography coupled with mass spectrometry, gas chromatography coupled with mass spectrometry, high performance liquid chromatography. Due to the complex composition of biological fluids a biological sample pre-treatment before the use of the method for quantitative determination is required in order to remove proteins and potential interferences. The most commonly used methods for processing biological samples containing metoprolol and bisoprolol were identified through a thorough literature search using PubMed, ScienceDirect, and Willey Journals databases. Articles published between years 2005-2015 were reviewed. Protein precipitation, liquid-liquid extraction and solid phase extraction are the main techniques for the extraction of these drugs from plasma, serum, whole blood and urine samples. In addition, numerous other techniques have been developed for the preparation of biological samples, such as dispersive liquid-liquid microextraction, carrier-mediated liquid phase microextraction, hollow fiber-protected liquid phase microextraction, on-line molecularly imprinted solid phase extraction. The analysis of metoprolol and bisoprolol in human plasma, urine and other biological fluids provides important information in clinical and toxicological trials, thus requiring the application of appropriate extraction techniques for the detection of these antihypertensive substances at nanogram and picogram levels.

  6. Using biological samples in epidemiological research on drugs of abuse

    Directory of Open Access Journals (Sweden)

    Hallvard Gjerde

    2011-12-01

    Full Text Available Blood, oral fluid (saliva, urine and hair are the most commonly used biological matrices for drug testing in epidemiological drug research. Other biological matrices may also be used for selected purposes. Blood reflects recent drug intake and may be used to assess impairment. Oral fluid reflects drug presence in blood and thereby also recent intake, but drug concentrations in this matrix cannot be used to accurately estimate concentrations in blood. Urine reflects drug use during the last few days and in some cases for a longer period, but does not indicate the dose size or frequency of use. Hair reflects drug use during several months, but is a poor matrix for detecting use of cannabis. If using a single drug dose, this can be detected in blood and urine if the sample is taken within the detection timeframes, in most cases also in oral fluid. Single drug use is most often insufficient for producing a positive test result in a sample of hair. For cocaine and amphetamine, weekly use may be needed, while for cannabis a positive result is not guaranteed even after daily use. Refusal rates are lowest for oral fluid and highest for blood and hair samples. The analytical costs are lowest for urine and highest for hair. Combined use of questionnaires/interviews and drug testing detects more drug use than when using only one of those methods and is therefore expected to give more accurate data.

  7. Putting humanity back into the teaching of human biology.

    Science.gov (United States)

    Donovan, Brian M

    2015-08-01

    In this paper, I draw upon debates about race in biology and philosophy as well as the concepts of ineliminable pluralism and psychological essentialism to outline the necessary subject matter knowledge that teachers should possess if they desire to: (i) increase student understanding of scientific research on genetic and behavioral variation in humans; and (ii) attenuate inegalitarian beliefs about race amongst students.

  8. Incubation Station for the Bacterial Growth Study in Biological Samples

    Directory of Open Access Journals (Sweden)

    Carlos Rafael Duharte Rodríguez

    2015-12-01

    Full Text Available This work shows the designing and characterization of a prototype of laboratory incubator as support of Microbiology research, in particular for the research of the bacterial growth in biological samples through optic methods (Turbidimetry and electrometric measurements of bioimpedance. It shows the results of simulation and experimentation of the design proposed for the canals of measurement of the variables: temperature and humidity, with a high linearity from the adequate selection of the corresponding sensors and the analogue components of every canal, controlled with help of a microcontroller AT89C51 (ATMEL with adequate benefi ts for this type of application.

  9. Cloning humans? Biological, ethical, and social considerations.

    Science.gov (United States)

    Ayala, Francisco J

    2015-07-21

    There are, in mankind, two kinds of heredity: biological and cultural. Cultural inheritance makes possible for humans what no other organism can accomplish: the cumulative transmission of experience from generation to generation. In turn, cultural inheritance leads to cultural evolution, the prevailing mode of human adaptation. For the last few millennia, humans have been adapting the environments to their genes more often than their genes to the environments. Nevertheless, natural selection persists in modern humans, both as differential mortality and as differential fertility, although its intensity may decrease in the future. More than 2,000 human diseases and abnormalities have a genetic causation. Health care and the increasing feasibility of genetic therapy will, although slowly, augment the future incidence of hereditary ailments. Germ-line gene therapy could halt this increase, but at present, it is not technically feasible. The proposal to enhance the human genetic endowment by genetic cloning of eminent individuals is not warranted. Genomes can be cloned; individuals cannot. In the future, therapeutic cloning will bring enhanced possibilities for organ transplantation, nerve cells and tissue healing, and other health benefits.

  10. A low temperature scanning force microscope for biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, Mats Gustaf Lennart [Univ. of California, Berkeley, CA (United States)

    1993-05-01

    An SFM has been constructed capable of operating at 143 K. Two contributions to SFM technology are described: a new method of fabricating tips, and new designs of SFM springs that significantly lower the noise level. The SFM has been used to image several biological samples (including collagen, ferritin, RNA, purple membrane) at 143 K and room temperature. No improvement in resolution resulted from 143 K operation; several possible reasons for this are discussed. Possibly sharper tips may help. The 143 K SFM will allow the study of new categories of samples, such as those prepared by freeze-frame, single molecules (temperature dependence of mechanical properties), etc. The SFM was used to cut single collagen molecules into segments with a precision of {le} 10 nm.

  11. Microsystem strategies for sample preparation in biological detection.

    Energy Technology Data Exchange (ETDEWEB)

    James, Conrad D.; Galambos, Paul C.; Bennett, Dawn Jonita (University of Maryland Baltimore County, Baltimore, MD); Manginell, Monica; Okandan, Murat; Acrivos, Andreas (The City College of New York, NY); Brozik, Susan Marie; Khusid, Boris (New Jersey Institute of Technology, Newark, NJ)

    2005-03-01

    The objective of this LDRD was to develop microdevice strategies for dealing with samples to be examined in biological detection systems. This includes three sub-components: namely, microdevice fabrication, sample delivery to the microdevice, and sample processing within the microdevice. The first component of this work focused on utilizing Sandia's surface micromachining technology to fabricate small volume (nanoliter) fluidic systems for processing small quantities of biological samples. The next component was to develop interfaces for the surface-micromachined silicon devices. We partnered with Micronics, a commercial company, to produce fluidic manifolds for sample delivery to our silicon devices. Pressure testing was completed to examine the strength of the bond between the pressure-sensitive adhesive layer and the silicon chip. We are also pursuing several other methods, both in house and external, to develop polymer-based fluidic manifolds for packaging silicon-based microfluidic devices. The second component, sample processing, is divided into two sub-tasks: cell collection and cell lysis. Cell collection was achieved using dielectrophoresis, which employs AC fields to collect cells at energized microelectrodes, while rejecting non-cellular particles. Both live and dead Staph. aureus bacteria have been collected using RF frequency dielectrophoresis. Bacteria have been separated from polystyrene microspheres using frequency-shifting dielectrophoresis. Computational modeling was performed to optimize device separation performance, and to predict particle response to the dielectrophoretic traps. Cell lysis is continuing to be pursued using microactuators to mechanically disrupt cell membranes. Novel thermal actuators, which can generate larger forces than previously tested electrostatic actuators, have been incorporated with and tested with cell lysis devices. Significant cell membrane distortion has been observed, but more experiments need to be

  12. Physical biology of human brain development

    Directory of Open Access Journals (Sweden)

    Silvia eBudday

    2015-07-01

    Full Text Available Neurodevelopment is a complex, dynamic process that involves a precisely orchestrated sequence of genetic, environmental, biochemical, and physical events. Developmental biology and genetics have shaped our understanding of the molecular and cellular mechanisms during neurodevelopment. Recent studies suggest that physical forces play a central role in translating these cellular mechanisms into the complex surface morphology of the human brain. However, the precise impact of neuronal differentiation, migration, and connection on the physical forces during cortical folding remains unknown. Here we review the cellular mechanisms of neurodevelopment with a view towards surface morphogenesis, pattern selection, and evolution of shape. We revisit cortical folding as the instability problem of constrained differential growth in a multi-layered system. To identify the contributing factors of differential growth, we map out the timeline of neurodevelopment in humans and highlight the cellular events associated with extreme radial and tangential expansion. We demonstrate how computational modeling of differential growth can bridge the scales-from phenomena on the cellular level towards form and function on the organ level-to make quantitative, personalized predictions. Physics-based models can quantify cortical stresses, identify critical folding conditions, rationalize pattern selection, and predict gyral wavelengths and gyrification indices. We illustrate that physical forces can explain cortical malformations as emergent properties of developmental disorders. Combining biology and physics holds promise to advance our understanding of human brain development and enable early diagnostics of cortical malformations with the ultimate goal to improve treatment of neurodevelopmental disorders including epilepsy, autism spectrum disorders, and schizophrenia.

  13. Physical biology of human brain development.

    Science.gov (United States)

    Budday, Silvia; Steinmann, Paul; Kuhl, Ellen

    2015-01-01

    Neurodevelopment is a complex, dynamic process that involves a precisely orchestrated sequence of genetic, environmental, biochemical, and physical events. Developmental biology and genetics have shaped our understanding of the molecular and cellular mechanisms during neurodevelopment. Recent studies suggest that physical forces play a central role in translating these cellular mechanisms into the complex surface morphology of the human brain. However, the precise impact of neuronal differentiation, migration, and connection on the physical forces during cortical folding remains unknown. Here we review the cellular mechanisms of neurodevelopment with a view toward surface morphogenesis, pattern selection, and evolution of shape. We revisit cortical folding as the instability problem of constrained differential growth in a multi-layered system. To identify the contributing factors of differential growth, we map out the timeline of neurodevelopment in humans and highlight the cellular events associated with extreme radial and tangential expansion. We demonstrate how computational modeling of differential growth can bridge the scales-from phenomena on the cellular level toward form and function on the organ level-to make quantitative, personalized predictions. Physics-based models can quantify cortical stresses, identify critical folding conditions, rationalize pattern selection, and predict gyral wavelengths and gyrification indices. We illustrate that physical forces can explain cortical malformations as emergent properties of developmental disorders. Combining biology and physics holds promise to advance our understanding of human brain development and enable early diagnostics of cortical malformations with the ultimate goal to improve treatment of neurodevelopmental disorders including epilepsy, autism spectrum disorders, and schizophrenia.

  14. The use of contrast agent for imaging biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Dammer, J; Sopko, V; Jakubek, J [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ 12800 Prague 2 (Czech Republic); Weyda, F, E-mail: jiri.dammer@utef.cvut.cz [Biological center of the Academy of Sciences of the Czech Republic, Institute of Entomology, Branisovska 31, CZ-37005 Ceske Budejovice (Czech Republic)

    2011-01-15

    The technique of X-ray transmission imaging has been available for over a century and is still among the fastest and easiest approaches to the studies of internal structure of biological samples. Recent advances in semiconductor technology have led to the development of new types of X-ray detectors with direct conversion of interacting X-ray photon to an electric signal. Semiconductor pixel detectors seem to be specially promising; compared to the film technique, they provide single-quantum and real-time digital information about the objects being studied. We describe the recently developed radiographic apparatus, equipped with Medipix2 semiconductor pixel detector. The detector is used as an imager that counts individual photons of ionizing radiation, emitted by an X-ray tube (micro- or nano-focus FeinFocus). Thanks to the wide dynamic range of the Medipix2 detector and its high spatial resolution better than 1{mu}m, the setup is particularly suitable for radiographic imaging of small biological samples, including in-vivo observations with contrast agent (Optiray). Along with the description of the apparatus we provide examples of the use iodine contrast agent as a tracer in various insects as model organisms. The motivation of our work is to develop our imaging techniques as non-destructive and non-invasive. Microradiographic imaging helps detect organisms living in a not visible environment, visualize the internal biological processes and also to resolve the details of their body (morphology). Tiny live insects are an ideal object for our studies.

  15. Integrated Modular Teaching of Human Biology for Primary Care Practitioners

    Science.gov (United States)

    Glasgow, Michael S.

    1977-01-01

    Describes the use of integrated modular teaching of the human biology component of the Health Associate Program at Johns Hopkins University, where the goal is to develop an understanding of the sciences as applied to primary care. Discussion covers the module sequence, the human biology faculty, goals of the human biology faculty, laboratory…

  16. The biology of human psychosexual differentiation.

    Science.gov (United States)

    Gooren, Louis

    2006-11-01

    Most attempts to identify biological underpinnings of gender identity and sexual orientation in humans have investigated effects of sex steroids, so pivotal in the differentiation of the genitalia, showing strong parallels between animals and the human. The information on humans is derived from the so-called 'experiments of nature', clinical entities with a lesser-than-normal androgen exposure in XY subjects and a higher than normal androgen exposure in XX subjects. Prenatal androgenization appears to predispose to a male gender identity development, but apparently not decisively since 40-50% of 46,XY intersexed children with a history of prenatal androgen exposure do not develop a male gender identity. Obviously, male-to-female transsexuals, with a normal androgen exposure prenatally (there is no serious evidence to the contrary) develop a female gender identity, through unknown biological mechanisms apparently overriding the effects of prenatal androgens. The latest studies in 46, XX subjects exposed to prenatal androgens show that prenatal androgenization of 46,XX fetuses leads to marked masculinization of later gender-related behavior but does not lead to gender confusion/dysphoria. The example of female-to-male transsexuals, without evidence of prenatal androgen exposure, indicates that a male gender identity can develop without a significant androgen stimulus. So we are far away from any comprehensive understanding of hormonal imprinting on gender identity formation. Brain studies in homosexuals have not held up in replication studies or are in need of replication in transsexuals. Genetic studies and the fraternal birth order hypothesis provide indications of familial clustering of homosexuality but in many homosexuals these genetic patterns cannot be identified. The biological explanations advanced for the birth order hypothesis lack any experimental support.

  17. Human biological monitoring of occupational genotoxic exposures

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Sorsa, M

    1993-01-01

    ) occupational exposure limit value of styrene in ambient air. The consideration of ethical issues in human genetic monitoring is an important but often overlooked aspect. This includes the scientific and preventional relevance of performing a test on individuals, pre- and post study information of donors......Human biological monitoring is a valuable tool for exposure assessment in groups of persons occupationally exposed to genotoxic agents. If the monitoring activity covers genetic material the term genetic monitoring is used. The methods used for genetic monitoring are either substance specific, e...... for and the biomonitoring results should preferentially be linked with accurate ambient air monitoring. In persons occupationally exposed to styrene the endpoints of DNA-damage and DNA-repair in genetic monitoring are methods of choice in exposure situations above the current Danish (25 ppm) or Finnish (20 ppm...

  18. Why Humans Die: an Unsolved Biological Problem

    Science.gov (United States)

    Azbel', Mark Ya.

    2004-03-01

    Mortality is an instrument of natural selection, thus its theories are evolutionary motivated. They imply its irreversibility and life history dependence. This is inconsistent with demographic and biodemographic data for evolutionary unprecedented well protected populations with abundant resources. A physical approach establishes a biologically unanticipated mechanism of their mortality. It is reversible, stepwise, rapidly switches from one mode to another, and yields an exact law for a dominant fraction of mortality whose heterogeneity in the population is within the specified limits. (Any population reduces to such restricted heterogeneity groups). The (properly scaled) law is universal, i.e. independent of genetics and conditions for species as remote as humans and flies. Its mortality may be eliminated. Until old age all other mechanisms contribute ˜10% of the total mortality, but thereafter they determine the ultimate lifespan. The universal law agrees with demographic and biodemographic data. It presents a new, biologically explicit, demographic approximation of the total mortality. It suggests a possibility of a rapid (within less than two years for humans) and significant decrease in mortality at any (but very old) age.

  19. Micro-radiography of biological samples with medical contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Dammer, J., E-mail: jiri.dammer@lf1.cuni.cz [Charles University in Prague, First Faculty of Medicine, Salmovská 1, 120 00 Prague 2 (Czech Republic); Hospital Na Bulovce, Department of Radiological Physics, Budinova 2, 180 81 Prague 8 (Czech Republic); Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Weyda, F. [Faculty of Science, University of South Bohemia, Branisovska 31, 370 05 Ceske Budejovice (Czech Republic); Benes, J. [Charles University in Prague, First Faculty of Medicine, Salmovská 1, 120 00 Prague 2 (Czech Republic); Sopko, V. [Hospital Na Bulovce, Department of Radiological Physics, Budinova 2, 180 81 Prague 8 (Czech Republic); Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Gelbic, I. [Biology Centre, AS CR, Institute of Entomology, Department of Biochemistry and Physiology, Branisovska 31, CZ-37005 Ceske Budejovice (Czech Republic)

    2013-12-01

    Micro-radiography is an imaging technique that uses X-rays to study the internal structures of objects. This fast and easy imaging tool is based on differential X-ray attenuation by various tissues and structures within biological samples. The experimental setup described is based on the semiconductor pixel X-ray detector Medipix2 and X-ray micro-focus tube. Our micro-radiographic system has been recently used not only for the examination of internal structures of various arthropods and other biological objects but also for tracing some processes in selected model species (we used living larvae of mosquito Culex quinquefasciatus). Low concentrations of iodine, lanthanum or gold particles were used as a tracer (contrast agent). Such contrast agents increase the absorption of X-rays and allow a better visibility of internal structures of model organisms (especially the various cavities, pores, etc.). In addition, the movement of tracers in selected timing experiments demonstrates some physiological functions of digestive and excretory system.

  20. Field-Flow Fractionation Analysis of Complex Biological Samples

    Directory of Open Access Journals (Sweden)

    Mijić, I.

    2014-03-01

    perpendicular field, FFF techniques can be divided into Sedimentation, Flow, Thermal, Electrical and Magnetic techniques. The FFF techniques versatility, advantages, disadvantages and wide-range application of every specified FFF technique are listed in this review article. Coupling of different FFF techniques with simple or more comprehensive detectors, such as UV/VIS, MALS or mass spectrometer (see Fig. 6 has established the FFF as an efficient and versatile technique. The successful implementation of the FFF technique in the analysis of complex biological samples would influence the future development and direction of the technique's development.

  1. RNA SAMPLE PREPARATION APPLIED TO GENE EXPRESSION PROFILING FOR THE HORSE BIOLOGICAL PASSPORT.

    Science.gov (United States)

    Bailly-Chouriberry, Ludovic; Baudoin, Florent; Cormant, Florence; Glavieux, Yohan; Loup, Benoit; Garcia, Patrice; Popot, Marie-Agnès; Bonnaire, Yves

    2017-04-05

    The improvement of doping control is an on-going race. Techniques to fight against doping are usually based on the direct detection of drugs or their metabolites by analytical methods such as chromatography hyphenated to mass spectrometry after ad hoc sample preparation. Nowadays, omic methods constitute an attractive development and advances have been achieved particularly by application of molecular biology tools for detection of anabolic androgenic steroids (AAS), erythropoiesis-stimulating agent (ESA) or to control human growth hormone misuses. These interesting results across different animal species have suggested that modification of gene expression offers promising new methods of improving the window of detection of banned substances by targeting their effects on blood cell gene expression. In this context, the present study describes the possibility of using a modified version of the dedicated Human IVD (in vitro Diagnostics) PAXgene® Blood RNA Kit for horse gene expression analysis in blood collected on PAXgene® tubes applied to the Horse Biological Passport. The commercial kit was only approved for human blood samples and has required an optimization of specific technical requirements for equine blood samples. Improvements and recommendations were achieved for sample collection, storage and RNA extraction procedure. Following these developments, RNA yield and quality were demonstrated to be suitable for downstream gene expression analysis by qPCR techniques.

  2. The Mathematical Biology of Human Infections

    Directory of Open Access Journals (Sweden)

    Martin A. Nowak

    1999-12-01

    Full Text Available Humans are constant victims of infectious diseases. Biomedical research during this century has led to important insights into the molecular details of immune defense. Yet, many questions relating to disease require a quantitative understanding of the complex systems that arise from the nonlinear interactions between populations of immune cells and infectious agents. Exploration of such questions has lead to a newly emerging field of mathematical biology describing the spread of infectious agents both within and between infected individuals. This essay will discuss simple and complex models of evolution, and the propagation of virus and prion infections. Such models provide new perspectives for our understanding of infectious disease and provide guidelines for interpreting experimental observation; they also define what needs to be measured to improve understanding.

  3. Biological impact of human embryonic stem cells.

    Science.gov (United States)

    Martín, Miguel; Menéndez, Pablo

    2012-01-01

    Research on human embryonic stem cells (hESCs) and induced pluripotent (iPS) stem cells is currently a field of great potential in biomedicine. These cells represent a highly valuable tool for developmental biology studies, disease models, and drug screening and toxicity. The ultimate goal of hESCs and iPS cell research is the treatment of diseases or disorders for which there is currently no treatment or existing therapies are only partially effective. Despite the disproportionate short-term hopes generated, which are putting too much pressure on scientists, the international scientific community is making rapid progress in understanding hESCs and iPS cells. Nonetheless, great efforts have to be made to provide an answer to still quite basic questions concerning their biology. Moreover, translation to clinical applications in cell replacement therapy requires prior solution to ethical barriers. The recent development of iPS cells has provided a strong alternative to overcome ethical issues concerning hESCs. However, an in-depth characterization of their genetic and epigenetic features, as well as their differentiation potential still remains to be undertaken. This chapter will describe, precisely, what the critical issues are, where scientific and ethical barriers stand, and how we are to overcome them. Only then, we shall finally discover whether hESCs and iPS cells will allow building reproducible disease models, and whether they really are a safe tool, with great potential for regenerative medicine.

  4. Automated force volume image processing for biological samples.

    Directory of Open Access Journals (Sweden)

    Pavel Polyakov

    Full Text Available Atomic force microscopy (AFM has now become a powerful technique for investigating on a molecular level, surface forces, nanomechanical properties of deformable particles, biomolecular interactions, kinetics, and dynamic processes. This paper specifically focuses on the analysis of AFM force curves collected on biological systems, in particular, bacteria. The goal is to provide fully automated tools to achieve theoretical interpretation of force curves on the basis of adequate, available physical models. In this respect, we propose two algorithms, one for the processing of approach force curves and another for the quantitative analysis of retraction force curves. In the former, electrostatic interactions prior to contact between AFM probe and bacterium are accounted for and mechanical interactions operating after contact are described in terms of Hertz-Hooke formalism. Retraction force curves are analyzed on the basis of the Freely Jointed Chain model. For both algorithms, the quantitative reconstruction of force curves is based on the robust detection of critical points (jumps, changes of slope or changes of curvature which mark the transitions between the various relevant interactions taking place between the AFM tip and the studied sample during approach and retraction. Once the key regions of separation distance and indentation are detected, the physical parameters describing the relevant interactions operating in these regions are extracted making use of regression procedure for fitting experiments to theory. The flexibility, accuracy and strength of the algorithms are illustrated with the processing of two force-volume images, which collect a large set of approach and retraction curves measured on a single biological surface. For each force-volume image, several maps are generated, representing the spatial distribution of the searched physical parameters as estimated for each pixel of the force-volume image.

  5. Automated Force Volume Image Processing for Biological Samples

    Science.gov (United States)

    Duan, Junbo; Duval, Jérôme F. L.; Brie, David; Francius, Grégory

    2011-01-01

    Atomic force microscopy (AFM) has now become a powerful technique for investigating on a molecular level, surface forces, nanomechanical properties of deformable particles, biomolecular interactions, kinetics, and dynamic processes. This paper specifically focuses on the analysis of AFM force curves collected on biological systems, in particular, bacteria. The goal is to provide fully automated tools to achieve theoretical interpretation of force curves on the basis of adequate, available physical models. In this respect, we propose two algorithms, one for the processing of approach force curves and another for the quantitative analysis of retraction force curves. In the former, electrostatic interactions prior to contact between AFM probe and bacterium are accounted for and mechanical interactions operating after contact are described in terms of Hertz-Hooke formalism. Retraction force curves are analyzed on the basis of the Freely Jointed Chain model. For both algorithms, the quantitative reconstruction of force curves is based on the robust detection of critical points (jumps, changes of slope or changes of curvature) which mark the transitions between the various relevant interactions taking place between the AFM tip and the studied sample during approach and retraction. Once the key regions of separation distance and indentation are detected, the physical parameters describing the relevant interactions operating in these regions are extracted making use of regression procedure for fitting experiments to theory. The flexibility, accuracy and strength of the algorithms are illustrated with the processing of two force-volume images, which collect a large set of approach and retraction curves measured on a single biological surface. For each force-volume image, several maps are generated, representing the spatial distribution of the searched physical parameters as estimated for each pixel of the force-volume image. PMID:21559483

  6. Human mammary microenvironment better regulates the biology of human breast cancer in humanized mouse model.

    Science.gov (United States)

    Zheng, Ming-Jie; Wang, Jue; Xu, Lu; Zha, Xiao-Ming; Zhao, Yi; Ling, Li-Jun; Wang, Shui

    2015-02-01

    During the past decades, many efforts have been made in mimicking the clinical progress of human cancer in mouse models. Previously, we developed a human breast tissue-derived (HB) mouse model. Theoretically, it may mimic the interactions between "species-specific" mammary microenvironment of human origin and human breast cancer cells. However, detailed evidences are absent. The present study (in vivo, cellular, and molecular experiments) was designed to explore the regulatory role of human mammary microenvironment in the progress of human breast cancer cells. Subcutaneous (SUB), mammary fat pad (MFP), and HB mouse models were developed for in vivo comparisons. Then, the orthotopic tumor masses from three different mouse models were collected for primary culture. Finally, the biology of primary cultured human breast cancer cells was compared by cellular and molecular experiments. Results of in vivo mouse models indicated that human breast cancer cells grew better in human mammary microenvironment. Cellular and molecular experiments confirmed that primary cultured human breast cancer cells from HB mouse model showed a better proliferative and anti-apoptotic biology than those from SUB to MFP mouse models. Meanwhile, primary cultured human breast cancer cells from HB mouse model also obtained the migratory and invasive biology for "species-specific" tissue metastasis to human tissues. Comprehensive analyses suggest that "species-specific" mammary microenvironment of human origin better regulates the biology of human breast cancer cells in our humanized mouse model of breast cancer, which is more consistent with the clinical progress of human breast cancer.

  7. Applications of PIXE to biological and biomedical samples at the university of gent

    Science.gov (United States)

    Maenhaut, W.; Vandenhaute, J.; Duflou, H.; De Reuck, J.

    1987-03-01

    The research on biological and biomedical samples, conducted at the University of Gent during the last 4-5 years and using PIXE as analytical technique, is presented. Our optimized sample/target preparation methods are described, and the accuracy and precision obtainable with them are discussed. Two comprehensive biological/biomedical research projects, initiated at Gent, are presented. The first aims at investigating possible trace element changes in tissues of experimental animals (rats) as a result of liver necrosis or cirrhosis, induced by intraperitoneal injection with CCl 4. The second project involves the determination of the regional distribution of trace elements in the human brain. Eight elements, i.e. K, Ca, Mn, Fe, Cu, Zn, Se and Rb, are being measured in up to 50 different regions of 12 normal brains, and in selected brain regions from patients with neurological disorders. Some of the results of the two projects are discussed.

  8. Decellularized Human Skeletal Muscle as Biologic Scaffold for Reconstructive Surgery

    Directory of Open Access Journals (Sweden)

    Andrea Porzionato

    2015-07-01

    Full Text Available Engineered skeletal muscle tissues have been proposed as potential solutions for volumetric muscle losses, and biologic scaffolds have been obtained by decellularization of animal skeletal muscles. The aim of the present work was to analyse the characteristics of a biologic scaffold obtained by decellularization of human skeletal muscles (also through comparison with rats and rabbits and to evaluate its integration capability in a rabbit model with an abdominal wall defect. Rat, rabbit and human muscle samples were alternatively decellularized with two protocols: n.1, involving sodium deoxycholate and DNase I; n.2, trypsin-EDTA and Triton X-NH4OH. Protocol 2 proved more effective, removing all cellular material and maintaining the three-dimensional networks of collagen and elastic fibers. Ultrastructural analyses with transmission and scanning electron microscopy confirmed the preservation of collagen, elastic fibres, glycosaminoglycans and proteoglycans. Implantation of human scaffolds in rabbits gave good results in terms of integration, although recellularization by muscle cells was not completely achieved. In conclusion, human skeletal muscles may be effectively decellularized to obtain scaffolds preserving the architecture of the extracellular matrix and showing mechanical properties suitable for implantation/integration. Further analyses will be necessary to verify the suitability of these scaffolds for in vitro recolonization by autologous cells before in vivo implantation.

  9. Assessment of the differential linear coherent scattering coefficient of biological samples

    Science.gov (United States)

    Conceição, A. L. C.; Antoniassi, M.; Poletti, M. E.

    2010-07-01

    New differential linear coherent scattering coefficient, μ CS, data for four biological tissue types (fat pork, tendon chicken, adipose and fibroglandular human breast tissues) covering a large momentum transfer interval (0.07≤ q≤70.5 nm -1), resulted from combining WAXS and SAXS data, are presented in order to emphasize the need to update the default data-base by including the molecular interference and the large-scale arrangements effect. The results showed that the differential linear coherent scattering coefficient demonstrates influence of the large-scale arrangement, mainly due to collagen fibrils for tendon chicken and fibroglandular breast samples, and triacylglycerides for fat pork and adipose breast samples at low momentum transfer region. While, at high momentum transfer, the μ CS reflects effects of molecular interference related to water for tendon chicken and fibroglandular samples and, fatty acids for fat pork and adipose samples.

  10. Population Biology, Conservation Biology, and the Future of Humanity.

    Science.gov (United States)

    Ehrlich, Paul R.

    1987-01-01

    Recounts some of the progress that has been made in the field of population biology. Presents some of the important advances made in the field, along with some of their applications to societal problems. Calls for more cooperation between population scientists and social scientists, and more environmental education for the public. (TW)

  11. Biological characteristics of five strains of Brucella isolated in frozen human blood samples%冻存人血中分离的5株布鲁杆菌的生物学特征分析

    Institute of Scientific and Technical Information of China (English)

    王锐泽; 皮鑫; 张翠; 刘新彬; 关超玲; 赵倩; 赵硕; 李萌; 甄清

    2015-01-01

    Objective To understand the survival situation of Brucella in frozen human blood samples.Methods Blood samples of outpatients with brucellosis were from the Songyuan Center for Disease Control and Prevention.Twenty-eight blood samples of patients who had a symptom of fever and epidemiological contact history were collected,which were kept in tubes containing sodium citrate anticoagulation,and stored in the fridge at-20 ℃.Isolation and culture of pathogen in frozen human blood samples were carried out.Suspected colonies were detected by Grams stain and microscope examination,then further tested by serum agglutination test with Brucella,A and M factors positive serum.The strains were detected with Brucella tautonym primers by multiplex-PCR amplification.Results In the twenty-eight blood samples frozen at different times,colonies were found in five samples after isolation and culture of pathogen for 4-5 d.The colonies were arranged in transparence,moist or milky lawn;the Grams staining was negative;serum agglutination test with Brucella,A and M factors positive serum were positive.Five strains of Brucella were preliminary considered as Brucella melitensis type 3.The freezing time of Brucella being isolated in five human blood samples was from 6 to 17 d.The results of multiplex-PCR showed that a band of 223 bp could be amplified from strains of Brucella abortus and Brucella melitensis,and that a band of 488 bp could be amplified from strain of Brucella abortus,and 310 bp from Brucella melitensis.The results of five tested strains were identical with those of Brucella melitensis.Conclusion Brucella could be survived in frozen human blood samples for a certain time,and multiplex-PCR amplification with Brucella tautonym primers could provide a basis for diagnose and treatment of Brucella.%目的 了解布鲁杆菌在冻存血液中的存活情况.方法 在松原市疾病预防控制中心布鲁杆菌病(简称布病)门诊就诊的人群中,收集有发热症状及

  12. Groundbreaking Mars Sample Return for Science and Human Exploration

    Science.gov (United States)

    Cohen, Barbara; Draper, David; Eppler, Dean; Treiman, Allan

    2012-01-01

    Partnerships between science and human exploration have recent heritage for the Moon (Lunar Precursor Robotics Program, LPRP) and nearearth objects (Exploration Precursor Robotics Program, xPRP). Both programs spent appreciable time and effort determining measurements needed or desired before human missions to these destinations. These measurements may be crucial to human health or spacecraft design, or may be desired to better optimize systems designs such as spacesuits or operations. Both LPRP and xPRP recommended measurements from orbit, by landed missions and by sample return. LPRP conducted the Lunar Reconnaissance Orbiter (LRO) and Lunar Crater Observation and Sensing Satellite (LCROSS) missions, providing high-resolution visible imagery, surface and subsurface temperatures, global topography, mapping of possible water ice deposits, and the biological effects of radiation [1]. LPRP also initiated a landed mission to provide dust and regolith properties, local lighting conditions, assessment of resources, and demonstration of precision landing [2]. This mission was canceled in 2006 due to funding shortfalls. For the Moon, adequate samples of rocks and regolith were returned by the Apollo and Luna programs to conduct needed investigations. Many near-earth asteroids (NEAs) have been observed from the Earth and several have been more extensively characterized by close-flying missions and landings (NEAR, Hayabusa, Rosetta). The current Joint Robotic Precursor Activity program is considering activities such as partnering with the New Frontiers mission OSIRIS-Rex to visit a NEA and return a sample to the Earth. However, a strong consensus of the NEO User Team within xPRP was that a dedicated mission to the asteroid targeted by humans is required [3], ideally including regolith sample return for more extensive characterization and testing on the Earth.

  13. Sampling strategy for estimating human exposure pathways to consumer chemicals

    Directory of Open Access Journals (Sweden)

    Eleni Papadopoulou

    2016-03-01

    Full Text Available Human exposure to consumer chemicals has become a worldwide concern. In this work, a comprehensive sampling strategy is presented, to our knowledge being the first to study all relevant exposure pathways in a single cohort using multiple methods for assessment of exposure from each exposure pathway. The selected groups of chemicals to be studied are consumer chemicals whose production and use are currently in a state of transition and are; per- and polyfluorinated alkyl substances (PFASs, traditional and “emerging” brominated flame retardants (BFRs and EBFRs, organophosphate esters (OPEs and phthalate esters (PEs. Information about human exposure to these contaminants is needed due to existing data gaps on human exposure intakes from multiple exposure pathways and relationships between internal and external exposure. Indoor environment, food and biological samples were collected from 61 participants and their households in the Oslo area (Norway on two consecutive days, during winter 2013-14. Air, dust, hand wipes, and duplicate diet (food and drink samples were collected as indicators of external exposure, and blood, urine, blood spots, hair, nails and saliva as indicators of internal exposure. A food diary, food frequency questionnaire (FFQ and indoor environment questionnaire were also implemented. Approximately 2000 samples were collected in total and participant views on their experiences of this campaign were collected via questionnaire. While 91% of our participants were positive about future participation in a similar project, some tasks were viewed as problematic. Completing the food diary and collection of duplicate food/drink portions were the tasks most frequent reported as “hard”/”very hard”. Nevertheless, a strong positive correlation between the reported total mass of food/drinks in the food record and the total weight of the food/drinks in the collection bottles was observed, being an indication of accurate performance

  14. An ESR study on biological dosimeters: Human hair

    Energy Technology Data Exchange (ETDEWEB)

    Colak, Seyda, E-mail: seyda@hacettepe.edu.t [Hacettepe University, Physics Engineering Department, 06800 Ankara (Turkey); Ozbey, Turan [Hacettepe University, Physics Engineering Department, 06800 Ankara (Turkey)

    2011-05-15

    In the present work, characteristic features of the radicals found in untreated, gamma and UV-irradiated and mechanical damaged human hair samples were investigated by ESR spectroscopy. Heights of the resonance peaks measured with respect to the spectrum base line were used to monitor microwave power, dose-response, storage time and temperature dependent kinetic features of the radical species contributing to the formation of recorded experimental ESR spectra. Peak heights and g-values (2.0037-2.0052) determined from recorded spectra of hair were color dependent with {Delta}Hpp-0.47 mT. The act of cutting hair samples gene rates sulfur centered radicals which are found in the a-keratin structure of hair. The variations of the peak heights with temperature were related with the water content found in the hair samples. In the 6-1100 Gy dose range, a linear + quadratic dose-response curve was recorded for hair and the mean radiation yield (G{sub mean}) was calculated to be 0.4. The gamma radiation induced radicals were stable for a several hours at room temperature storage conditions. Based on these findings it was concluded that human hair samples could be used as biological/personnel dosimeters and that ESR spectroscopy could be successfully used as a potential technique for monitoring its dosimetric behaviours.

  15. Applications of a DAD-HPLC method for determination of loratadine on biological samples

    Directory of Open Access Journals (Sweden)

    Pavalache Georgeta

    2015-06-01

    Full Text Available The aim of research is to assess the active substance by a HPLC method for the separation and quantitative determination of loratadine. The method has been developed and validated on the standard solutions, in previous research. The current study was undertaken to present the results obtained from loratadine determination in biological samples (human serum, urine and breast milk. These results may be applicable on patients with different physiological conditions (aging, pregnancy or recently giving birth, etc. and pathological conditions which may interfere with the metabolism of loratadine. The used HPLC method detected loratadine concentrations in human serum samples, respectively urine samples, at 2 hours after drug administration. The method detected traces of loratadine which passed into breast milk, as well. Data were statistically interpreted using MED CALC 10.2 software. These results show that the applied method can be used for quantitative analysis of loratadine in biological fluids (all permissible limits of quality specifications being in the range 95- 105%.

  16. Human biological monitoring of suspected endocrine-disrupting compounds

    OpenAIRE

    Moosa Faniband; Lindh, Christian H; Bo AG Jönsson

    2014-01-01

    Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and o...

  17. Stem Cells: A Renaissance in Human Biology Research.

    Science.gov (United States)

    Wu, Jun; Izpisua Belmonte, Juan Carlos

    2016-06-16

    The understanding of human biology and how it relates to that of other species represents an ancient quest. Limited access to human material, particularly during early development, has restricted researchers to only scratching the surface of this inherently challenging subject. Recent technological innovations, such as single cell "omics" and human stem cell derivation, have now greatly accelerated our ability to gain insights into uniquely human biology. The opportunities afforded to delve molecularly into scarce material and to model human embryogenesis and pathophysiological processes are leading to new insights of human development and are changing our understanding of disease and choice of therapy options.

  18. The biology of human sexuality: evolution, ecology and physiology

    OpenAIRE

    PW Bateman; NC Bennett

    2006-01-01

    Many evolutionary biologists argue that human sexual behaviour can be studied in exactly the same way as that of other species. Many sociologists argue that social influences effectively obscure, and are more important than, a reductionist biological approach to human sexual behaviour. Here,we authors attempt to provide a broad introduction to human sexual behaviour from a biological standpoint and to indicate where the ambiguous areas are. We outline the evolutionary selective pressures that...

  19. Quantitative mass spectrometry of unconventional human biological matrices

    Science.gov (United States)

    Dutkiewicz, Ewelina P.; Urban, Pawel L.

    2016-10-01

    The development of sensitive and versatile mass spectrometric methodology has fuelled interest in the analysis of metabolites and drugs in unconventional biological specimens. Here, we discuss the analysis of eight human matrices-hair, nail, breath, saliva, tears, meibum, nasal mucus and skin excretions (including sweat)-by mass spectrometry (MS). The use of such specimens brings a number of advantages, the most important being non-invasive sampling, the limited risk of adulteration and the ability to obtain information that complements blood and urine tests. The most often studied matrices are hair, breath and saliva. This review primarily focuses on endogenous (e.g. potential biomarkers, hormones) and exogenous (e.g. drugs, environmental contaminants) small molecules. The majority of analytical methods used chromatographic separation prior to MS; however, such a hyphenated methodology greatly limits analytical throughput. On the other hand, the mass spectrometric methods that exclude chromatographic separation are fast but suffer from matrix interferences. To enable development of quantitative assays for unconventional matrices, it is desirable to standardize the protocols for the analysis of each specimen and create appropriate certified reference materials. Overcoming these challenges will make analysis of unconventional human biological matrices more common in a clinical setting. This article is part of the themed issue 'Quantitative mass spectrometry'.

  20. Spectroscopic analysis of bosentan in biological samples after a liquid-liquid microextraction

    Directory of Open Access Journals (Sweden)

    Sanaz Sajedi-Amin

    2015-12-01

    Conclusion: A simple, low cost, precise and accurate spectrophotometric analysis of bosentan in biological samples after liquid-liquid microextraction were developed and validated for routine analyses.

  1. Integration of culture and biology in human development.

    Science.gov (United States)

    Mistry, Jayanthi

    2013-01-01

    The challenge of integrating biology and culture is addressed in this chapter by emphasizing human development as involving mutually constitutive, embodied, and epigenetic processes. Heuristically rich constructs extrapolated from cultural psychology and developmental science, such as embodiment, action, and activity, are presented as promising approaches to the integration of cultural and biology in human development. These theoretical notions are applied to frame the nascent field of cultural neuroscience as representing this integration of culture and biology. Current empirical research in cultural neuroscience is then synthesized to illustrate emerging trends in this body of literature that examine the integration of biology and culture.

  2. Determination of steroid hormones in biological and environmental samples using green microextraction techniques: an overview.

    Science.gov (United States)

    Aufartová, Jana; Mahugo-Santana, Cristina; Sosa-Ferrera, Zoraida; Santana-Rodríguez, José Juan; Nováková, Lucie; Solich, Petr

    2011-10-17

    Residues of steroid hormones have become a cause for concern because they can affect the biological activity of non-target organisms. Steroid hormones are a potential risk for wildlife and humans through the consumption of contaminated food or water. Their determination requires extraction and clean-up steps, prior to detection, to reach low concentration levels. In recent years, a great effort has been made to develop new analytical methodologies, such as microextraction techniques, that reduce environmental pollution. Researchers have modified old methods to incorporate procedures that use less-hazardous chemicals or that use smaller amounts of them. They are able to do direct analysis using miniaturised equipment and reduced amounts of solvents and wastes. These accomplishments are the main objectives of green analytical chemistry. In this overview, we focus on microextraction techniques for the determination of steroid hormones in biological (e.g., human urine, human serum, fish, shrimp and prawn tissue and milk) and environmental (e.g., wastewaters, surface waters, tap waters, river waters, sewage sludges, marine sediments and river sediments) samples. We comment on the most recent applications in sorptive-microextraction modes, such as solid phase microextraction (SPME) with molecularly imprinted polymers (MIPs), in-tube solid-phase microextraction (IT-SPME), stir-bar sorptive extraction (SBSE) and microextraction in packed sorbent (MEPS). We also describe liquid-phase microextraction (LPME) approaches reported in the literature that are applied to the determination of steroid hormones.

  3. Analytical Methodologies for the Determination of Endocrine Disrupting Compounds in Biological and Environmental Samples

    Science.gov (United States)

    Sosa-Ferrera, Zoraida; Mahugo-Santana, Cristina; Santana-Rodríguez, José Juan

    2013-01-01

    Endocrine-disruptor compounds (EDCs) can mimic natural hormones and produce adverse effects in the endocrine functions by interacting with estrogen receptors. EDCs include both natural and synthetic chemicals, such as hormones, personal care products, surfactants, and flame retardants, among others. EDCs are characterised by their ubiquitous presence at trace-level concentrations and their wide diversity. Since the discovery of the adverse effects of these pollutants on wildlife and human health, analytical methods have been developed for their qualitative and quantitative determination. In particular, mass-based analytical methods show excellent sensitivity and precision for their quantification. This paper reviews recently published analytical methodologies for the sample preparation and for the determination of these compounds in different environmental and biological matrices by liquid chromatography coupled with mass spectrometry. The various sample preparation techniques are compared and discussed. In addition, recent developments and advances in this field are presented. PMID:23738329

  4. Analytical methodologies for the determination of endocrine disrupting compounds in biological and environmental samples.

    Science.gov (United States)

    Sosa-Ferrera, Zoraida; Mahugo-Santana, Cristina; Santana-Rodríguez, José Juan

    2013-01-01

    Endocrine-disruptor compounds (EDCs) can mimic natural hormones and produce adverse effects in the endocrine functions by interacting with estrogen receptors. EDCs include both natural and synthetic chemicals, such as hormones, personal care products, surfactants, and flame retardants, among others. EDCs are characterised by their ubiquitous presence at trace-level concentrations and their wide diversity. Since the discovery of the adverse effects of these pollutants on wildlife and human health, analytical methods have been developed for their qualitative and quantitative determination. In particular, mass-based analytical methods show excellent sensitivity and precision for their quantification. This paper reviews recently published analytical methodologies for the sample preparation and for the determination of these compounds in different environmental and biological matrices by liquid chromatography coupled with mass spectrometry. The various sample preparation techniques are compared and discussed. In addition, recent developments and advances in this field are presented.

  5. A microbial perspective of human developmental biology.

    Science.gov (United States)

    Charbonneau, Mark R; Blanton, Laura V; DiGiulio, Daniel B; Relman, David A; Lebrilla, Carlito B; Mills, David A; Gordon, Jeffrey I

    2016-07-07

    When most people think of human development, they tend to consider only human cells and organs. Yet there is another facet that involves human-associated microbial communities. A microbial perspective of human development provides opportunities to refine our definitions of healthy prenatal and postnatal growth and to develop innovative strategies for disease prevention and treatment. Given the dramatic changes in lifestyles and disease patterns that are occurring with globalization, we issue a call for the establishment of 'human microbial observatories' designed to examine microbial community development in birth cohorts representing populations with diverse anthropological characteristics, including those undergoing rapid change.

  6. Metagenomic Systems Biology of the Human Microbiome

    DEFF Research Database (Denmark)

    Bonde, Ida

    The human microbiome is an integrated part of the human body, outnumbering the human cells by approximately a factor 10. These microorganisms are very important for human health, hence knowledge about this, ”our other genome”, has been growing rapidly in recent years. This is manly due to the adv......The human microbiome is an integrated part of the human body, outnumbering the human cells by approximately a factor 10. These microorganisms are very important for human health, hence knowledge about this, ”our other genome”, has been growing rapidly in recent years. This is manly due...... in the system. Applying the CAG clustering method to data from the human gut microbiome, we identified dependency-associations between plasmids, phages and clone-specific gene sets to their bacterial host. Connections between CRISPR-elements and phages were also observed. Additionally, the persistence of some...... bacterial species in the human gut could be predicted based on absence or presence of specific genetic modules. Based on the same CAG clustering of the human gut microbiome data, the link between bile acid degradation of bacteria in the gut and obesity was investigated. There seemed to be a slight...

  7. Teacher's Study Guide on the Biology of Human Populations: Africa.

    Science.gov (United States)

    United Nations Educational, Scientific, and Cultural Organization, Paris (France).

    This teacher's guide is designed to give background information on current biological subjects not usually treated in student texts. The book is divided into five parts, each representing one of the following topics: (1) evolution of human populations; (2) environment of human populations; (3) dynamics of human populations; (4) reproduction in…

  8. Cultural Carrying Capacity: A Biological Approach to Human Problems.

    Science.gov (United States)

    Hardin, Garrett

    1992-01-01

    In discussing the human and cultural implications of scientific discoveries and knowledge, the biological concept of carrying capacity is explored. Maintaining that human beings are truly animals answering to principles that govern all animals, the author addresses the need for human populations to work within the context of culture and carrying…

  9. Cellular characterization of compression induced-damage in live biological samples

    Science.gov (United States)

    Bo, Chiara; Balzer, Jens; Hahnel, Mark; Rankin, Sara M.; Brown, Katherine A.; Proud, William G.

    2011-06-01

    Understanding the dysfunctions that high-intensity compression waves induce in human tissues is critical to impact on acute-phase treatments and requires the development of experimental models of traumatic damage in biological samples. In this study we have developed an experimental system to directly assess the impact of dynamic loading conditions on cellular function at the molecular level. Here we present a confinement chamber designed to subject live cell cultures in liquid environment to compression waves in the range of tens of MPa using a split Hopkinson pressure bars system. Recording the loading history and collecting the samples post-impact without external contamination allow the definition of parameters such as pressure and duration of the stimulus that can be related to the cellular damage. The compression experiments are conducted on Mesenchymal Stem Cells from BALB/c mice and the damage analysis are compared to two control groups. Changes in Stem cell viability, phenotype and function are assessed flow cytometry and with in vitro bioassays at two different time points. Identifying the cellular and molecular mechanisms underlying the damage caused by dynamic loading in live biological samples could enable the development of new treatments for traumatic injuries.

  10. Raymond Pearl and the shaping of human biology.

    Science.gov (United States)

    Little, Michael A; Garruto, Ralph M

    2010-02-01

    Raymond Pearl (1879-1940) was a significant figure in the field of biology. He founded the journal Human Biology and almost single-handedly promoted and established the scientific discipline of human biology. His scientific versatility was one of his most important features during the first four decades of the 20th century, and he played a major role in developing the fields of biodemography, human population biology, human life-cycle and life span approaches, fertility, growth, the biology of longevity and senescence, and mortality. He was one of the earliest biologists to combine biometric analyses and experimental studies to explore the dimensions of human biology. Pearl also was broadly educated in the arts, music, literature, history, the classics, and science. His writing was sophisticated and often witty, and his views were sometimes provocative and controversial. His network of colleagues and friends among the literary and science worlds was substantial. The following biographical memoir of Raymond Pearl is designed to commemorate the 80th anniversary of the founding of his journal Human Biology and is a tribute to this great scientist. Pearl's sudden death at age 61 truncated a scientific career that was one of the most productive of the 20th century.

  11. Evaluation of arsenic, cobalt, copper and manganese in biological Samples of Steel mill workers by electrothermal atomic absorption Spectrometry.

    Science.gov (United States)

    Afridi, H I; Kazi, T G; Kazi, N G; Jamali, M K; Arain, M B; Sirajuddin; Kandhro, G A; Shah, A Q; Baig, J A

    2009-02-01

    The determination of trace and toxic elements in biological samples (blood, urine and scalp hair samples) of human beings is an important clinical test. The aim of our present study was to determine the concentration of arsenic (As), copper (Cu), cobalt (Co) and manganese (Mn), in biological samples of male production workers (PW) and quality control workers (QW) of steel mill, with aged 25-55 years, to assess the possible influence of environmental exposure. For comparison purpose, the same biological samples of unexposed healthy males of same age group were collected as control subjects. The determination of all elements in biological samples was carried out by electrothermal atomic absorption spectrometry, prior to microwave assisted acid digestion. The accuracy of the As, Cu, Co and Mn measurements was tested by simultaneously analyzing certified reference materials (CRMs) and for comparative purposes conventional wet acid digestion method was used on the same CRMs. No significant differences were observed between the analytical results and the certified values, using both methods (paired t-test at P > 0.05). The results indicate that concentrations of As, Cu, Co and Mn in all three biological samples of the exposed workers (QW and PW) were significantly higher than those of the controls. The possible correlation of these elements with the etiology of different physiological disorders is discussed. The results were also demonstrated the need of attention for improvements in workplace, ventilation and industrial hygiene practices.

  12. Alteration of biological samples in speciation analysis of metalloproteins.

    Science.gov (United States)

    Wolf, Christian; Wenda, Nadine; Richter, Andrea; Kyriakopoulos, Antonios

    2007-10-01

    For investigations of metalloproteins by speciation analysis, the integrity of the protein-metal complexes before and during separation is crucial. Knowledge about potential alterations of the samples is thus essential to avoid misinterpretations of the analytical results. Chromatographic element profiles of different cytosolic samples from animal tissues were measured repeatedly to estimate the sample stability. The dependence of the signals on the dwell time of the sample in an autosampling device at 4 degrees C for a period of 10 h was observed. Alterations in the element content of different metal-containing fractions were quantified by means of recovery values. Some metalloprotein fractions (e.g. approximately 27-kDa arsenic, approximately 27-kDa iron and different zinc fractions) were stable or only minor alterations were observed and for their investigation an autosampling device is therefore suitable. However, most of the other metalloprotein fractions, especially nickel-containing proteins, showed major alterations: these samples should therefore be analysed immediately after preparation or directly after thawing.

  13. Determination of platinum, palladium, and lead in biological samples by atomic absorption spectrophotometry.

    Science.gov (United States)

    Tillery, J B; Johnson, D E

    1975-01-01

    A flameless atomic absorption method for the coextraction of platinum and palladium from biological and environmental samples by high molecular weight amine (HMWA) is given. Also, methods for lead determination in biological samples by use of extraction flameless analysis and direct aspiration-flame analysis are reported. A study of lead contamination of Vacutainer tubes is given. PMID:1227857

  14. Insights on antioxidant assays for biological samples based on the reduction of copper complexes-the importance of analytical conditions.

    Science.gov (United States)

    Marques, Sara S; Magalhães, Luís M; Tóth, Ildikó V; Segundo, Marcela A

    2014-06-25

    Total antioxidant capacity assays are recognized as instrumental to establish antioxidant status of biological samples, however the varying experimental conditions result in conclusions that may not be transposable to other settings. After selection of the complexing agent, reagent addition order, buffer type and concentration, copper reducing assays were adapted to a high-throughput scheme and validated using model biological antioxidant compounds of ascorbic acid, Trolox (a soluble analogue of vitamin E), uric acid and glutathione. A critical comparison was made based on real samples including NIST-909c human serum certified sample, and five study samples. The validated method provided linear range up to 100 µM Trolox, (limit of detection 2.3 µM; limit of quantification 7.7 µM) with recovery results above 85% and precision <5%. The validated developed method with an increased sensitivity is a sound choice for assessment of TAC in serum samples.

  15. Insights on Antioxidant Assays for Biological Samples Based on the Reduction of Copper Complexes—The Importance of Analytical Conditions

    Directory of Open Access Journals (Sweden)

    Sara S. Marques

    2014-06-01

    Full Text Available Total antioxidant capacity assays are recognized as instrumental to establish antioxidant status of biological samples, however the varying experimental conditions result in conclusions that may not be transposable to other settings. After selection of the complexing agent, reagent addition order, buffer type and concentration, copper reducing assays were adapted to a high-throughput scheme and validated using model biological antioxidant compounds of ascorbic acid, Trolox (a soluble analogue of vitamin E, uric acid and glutathione. A critical comparison was made based on real samples including NIST-909c human serum certified sample, and five study samples. The validated method provided linear range up to 100 µM Trolox, (limit of detection 2.3 µM; limit of quantification 7.7 µM with recovery results above 85% and precision <5%. The validated developed method with an increased sensitivity is a sound choice for assessment of TAC in serum samples.

  16. Human biological monitoring of suspected endocrine-disrupting compounds

    Science.gov (United States)

    Faniband, Moosa; Lindh, Christian H; Jönsson, Bo AG

    2014-01-01

    Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and organic solvents. The aspects discussed are origin to exposure, metabolism, matrices to analyse, analytical determination methods, determinants, and time trends. PMID:24369128

  17. Human biological monitoring of suspected endocrine-disrupting compounds.

    Science.gov (United States)

    Faniband, Moosa; Lindh, Christian H; Jönsson, Bo A G

    2014-01-01

    Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and organic solvents. The aspects discussed are origin to exposure, metabolism, matrices to analyse, analytical determination methods, determinants, and time trends.

  18. Deep Penetration of Charged Particles in Biological Samples

    Institute of Scientific and Technical Information of China (English)

    WANG Rui-Jin; MU Yu-Guang; ZHAO Ming-Wen; MA Yu-Chen; XIA Yue-Yuan; LIU Xiang-Dong; LIU Ji-Tian; ZHANG Jian-Hua; YU Zeng-Liang

    2001-01-01

    Experimental evidence of abnormally deep penetration in some botanical targets by low-energy ion beams is presented. The energy spectra of 818kev He+ ions penetrating a 70μm thick seed coat of maize, fruit peel of grape and of tomato all have a common feature. The leading edges of these broad spectra indicate that some of the penetrating ions pass through the thick targets easily and only lose a small fraction of their initial incident energy. Rutherford backscattering spectrometry and electron microprobe measurements are used to determine the argon concentration in multilayer samples of the seed coat of maize implanted by 200 kev Ar+ ions. The results show that about 10% of the Ar+ ions can penetrate deeper than ~l00 μm in these samples.

  19. Deep Penetration of Charged Particles in Biological Samples

    Science.gov (United States)

    Wang, Rui-Jin; Xia, Yue-Yuan; Mu, Yu-Guang; Zhao, Ming-Wen; Ma, Yu-Chen; Liu, Xiang-Dong; Zhang, Jian-Hua; Liu, Ji-Tian; Yu, Zeng-Liang

    2001-02-01

    Experimental evidence of abnormally deep penetration in some botanical targets by low-energy ion beams is presented. The energy spectra of 818 keV He+ ions penetrating a 70 µm thick seed coat of maize, fruit peel of grape and of tomato all have a common feature. The leading edges of these broad spectra indicate that some of the penetrating ions pass through the thick targets easily and only lose a small fraction of their initial incident energy. Rutherford backscattering spectrometry and electron microprobe measurements are used to determine the argon concentration in multilayer samples of the seed coat of maize implanted by 200 keV Ar+ ions. The results show that about 10% of the Ar+ ions can penetrate deeper than ~100 µm in these samples.

  20. Micro-differential scanning calorimeter for liquid biological samples

    Science.gov (United States)

    Wang, Shuyu; Yu, Shifeng; Siedler, Michael S.; Ihnat, Peter M.; Filoti, Dana I.; Lu, Ming; Zuo, Lei

    2016-10-01

    We developed an ultrasensitive micro-DSC (differential scanning calorimeter) for liquid protein sample characterization. This design integrated vanadium oxide thermistors and flexible polymer substrates with microfluidics chambers to achieve a high sensitivity (6 V/W), low thermal conductivity (0.7 mW/K), high power resolutions (40 nW), and well-defined liquid volume (1 μl) calorimeter sensor in a compact and cost-effective way. We further demonstrated the performance of the sensor with lysozyme unfolding. The measured transition temperature and enthalpy change were in accordance with the previous literature data. This micro-DSC could potentially raise the prospect of high-throughput biochemical measurement by parallel operation with miniaturized sample consumption.

  1. Dielectric characterisation of human tissue samples

    NARCIS (Netherlands)

    Rossum, W.L. van; Nennie, F.; Deiana, D.; Veen, A.J. van der; Monni, S.

    2014-01-01

    The electrical properties of tissues samples are required for investigation and simulation purposes in biomedical applications of EM sensors. While available open literature mostly deals with ex-vivo characterization of isolated tissues, knowledge on dielectric properties of these tissues in their o

  2. Study on immunocapture-chemiluminescence assay of lipase activity in a biological sample.

    Science.gov (United States)

    Ichibangase, Tomoko; Hamabe, Chie; Ohba, Yoshihito; Kishikawa, Naoya; Nakashima, Kenichiro; Kayamori, Yuzo; Kang, Dongchon; Hamasaki, Naotaka; Kuroda, Naotaka

    2006-01-01

    A new approach for the determination of lipase (triacylglycerol lipase, EC.3.1.1.3) activity in a biological sample was investigated by combining an immunocapture technique with a chemiluminescence (CL) assay method in order to eliminate interference with CL detection. The proposed method consists of an immunocapture step to trap lipase and a subsequent step for CL detection of the activity of the captured lipase. The CL detection is based on the luminol-hydrogen peroxide (H(2)O(2))-horseradish peroxidase (HRP) reaction and utilizes a proenhancer substrate [a lauric acid ester of 2-(4-hydroxyphenyl)-4,5-diphenylimidazole (HDI)] which liberates an active enhancer, HDI, by enzymatic hydrolysis. A polyclonal antibody prepared with porcine pancreas lipase was used for the immunocapture. The proposed immunocapture-CL method effectively eliminated the interference with the CL reaction from biological components and enabled the determination of spiked porcine pancreas lipase activity in serum samples in the range 0.41-1.1 U(HDI) (1 U(HDI) corresponds to the amount which liberates 1 pmol HDI/min at 37 degrees C from the substrate). The method was further applied to the assay of the activity for human pancreas lipase in serum and the results showed good correlation (r = 0.871) with those by the conventional colorimetric method.

  3. Pattern designation of PCBs in human samples

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, M.S.; Fischbein, A.; Rosenman, K.D.; Levin, S.M.

    1986-03-01

    In order to asses the nature of PCB exposures in humans, statistical measures of PCB patterns in blood serum (as Aroclor 1254 or 1260) were made in 348 cases, representing several exposed and non-exposed groups. Although the cases were not representative of any population, most (252/348) had an Arcolor 1260 pattern, with evidence that PCB congeners in blood serum were usually derived from both Aroclor 1254 and 1260. The method is readily applied to routine packed column gc analysis.

  4. Elemental distribution and sample integrity comparison of freeze-dried and frozen-hydrated biological tissue samples with nuclear microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Vavpetič, P., E-mail: primoz.vavpetic@ijs.si [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Vogel-Mikuš, K. [Biotechnical Faculty, Department of Biology, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana (Slovenia); Jeromel, L. [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Ogrinc Potočnik, N. [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); FOM-Institute AMOLF, Science Park 104, 1098 XG Amsterdam (Netherlands); Pongrac, P. [Biotechnical Faculty, Department of Biology, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana (Slovenia); Department of Plant Physiology, University of Bayreuth, Universitätstr. 30, 95447 Bayreuth (Germany); Drobne, D.; Pipan Tkalec, Ž.; Novak, S.; Kos, M.; Koren, Š.; Regvar, M. [Biotechnical Faculty, Department of Biology, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana (Slovenia); Pelicon, P. [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia)

    2015-04-01

    The analysis of biological samples in frozen-hydrated state with micro-PIXE technique at Jožef Stefan Institute (JSI) nuclear microprobe has matured to a point that enables us to measure and examine frozen tissue samples routinely as a standard research method. Cryotome-cut slice of frozen-hydrated biological sample is mounted between two thin foils and positioned on the sample holder. The temperature of the cold stage in the measuring chamber is kept below 130 K throughout the insertion of the samples and the proton beam exposure. Matrix composition of frozen-hydrated tissue is consisted mostly of ice. Sample deterioration during proton beam exposure is monitored during the experiment, as both Elastic Backscattering Spectrometry (EBS) and Scanning Transmission Ion Microscopy (STIM) in on–off axis geometry are recorded together with the events in two PIXE detectors and backscattered ions from the chopper in a single list-mode file. The aim of this experiment was to determine differences and similarities between two kinds of biological sample preparation techniques for micro-PIXE analysis, namely freeze-drying and frozen-hydrated sample preparation in order to evaluate the improvements in the elemental localisation of the latter technique if any. In the presented work, a standard micro-PIXE configuration for tissue mapping at JSI was used with five detection systems operating in parallel, with proton beam cross section of 1.0 × 1.0 μm{sup 2} and a beam current of 100 pA. The comparison of the resulting elemental distributions measured at the biological tissue prepared in the frozen-hydrated and in the freeze-dried state revealed differences in elemental distribution of particular elements at the cellular level due to the morphology alteration in particular tissue compartments induced either by water removal in the lyophilisation process or by unsatisfactory preparation of samples for cutting and mounting during the shock-freezing phase of sample preparation.

  5. Elemental distribution and sample integrity comparison of freeze-dried and frozen-hydrated biological tissue samples with nuclear microprobe

    Science.gov (United States)

    Vavpetič, P.; Vogel-Mikuš, K.; Jeromel, L.; Ogrinc Potočnik, N.; Pongrac, P.; Drobne, D.; Pipan Tkalec, Ž.; Novak, S.; Kos, M.; Koren, Š.; Regvar, M.; Pelicon, P.

    2015-04-01

    The analysis of biological samples in frozen-hydrated state with micro-PIXE technique at Jožef Stefan Institute (JSI) nuclear microprobe has matured to a point that enables us to measure and examine frozen tissue samples routinely as a standard research method. Cryotome-cut slice of frozen-hydrated biological sample is mounted between two thin foils and positioned on the sample holder. The temperature of the cold stage in the measuring chamber is kept below 130 K throughout the insertion of the samples and the proton beam exposure. Matrix composition of frozen-hydrated tissue is consisted mostly of ice. Sample deterioration during proton beam exposure is monitored during the experiment, as both Elastic Backscattering Spectrometry (EBS) and Scanning Transmission Ion Microscopy (STIM) in on-off axis geometry are recorded together with the events in two PIXE detectors and backscattered ions from the chopper in a single list-mode file. The aim of this experiment was to determine differences and similarities between two kinds of biological sample preparation techniques for micro-PIXE analysis, namely freeze-drying and frozen-hydrated sample preparation in order to evaluate the improvements in the elemental localisation of the latter technique if any. In the presented work, a standard micro-PIXE configuration for tissue mapping at JSI was used with five detection systems operating in parallel, with proton beam cross section of 1.0 × 1.0 μm2 and a beam current of 100 pA. The comparison of the resulting elemental distributions measured at the biological tissue prepared in the frozen-hydrated and in the freeze-dried state revealed differences in elemental distribution of particular elements at the cellular level due to the morphology alteration in particular tissue compartments induced either by water removal in the lyophilisation process or by unsatisfactory preparation of samples for cutting and mounting during the shock-freezing phase of sample preparation.

  6. [Human angiogenin: expression, purification, biological assay].

    Science.gov (United States)

    Yang, H; Zhang, Y Q; Yan, Z; Han, W; Yao, L B; Su, C Z

    2001-01-01

    Angiogenin cDNA was obtained by RT-PCR, and cloned into the fusion expression vector pRSETB. The recombinant Angiogenin protein was fused with His6 at its N-terminal and expressed as inclusion body. The expression level was about 10% of the total bacteria protein. After dissolved in 8 mol/L urea, the recombinant protein was purified by Ni2(+)-NTA chelating resin, according to the high affinity of His6 with Ni2+. The biological assay indicated that purified rhANG could induced the new blood vessel formation of CAM and degraded tRNA in vitro.

  7. Nanocharacterization of Soft Biological Samples in Shear Mode with Quartz Tuning Fork Probes

    OpenAIRE

    Manel Puig-Vidal; Laura Gonzalez; Jorge Otero

    2012-01-01

    Quartz tuning forks are extremely good resonators and their use is growing in scanning probe microscopy. Nevertheless, only a few studies on soft biological samples have been reported using these probes. In this work, we present the methodology to develop and use these nanosensors to properly work with biological samples. The working principles, fabrication and experimental setup are presented. The results in the nanocharacterization of different samples in different ambients are presented by...

  8. Multiphoton imaging of biological samples during freezing and heating

    Science.gov (United States)

    Breunig, H. G.; Uchugonova, A.; König, K.

    2014-02-01

    We applied multiphoton microscopic imaging to observe freezing and heating effects in plant- and animal cell samples. The experimental setups consisted of a multiphoton imaging system and a heating and cooling stage which allows for precise temperature control from liquid nitrogen temperature (-196°C 77 K) up to +600°C (873 K) with heating/freezing rates between 0.01 K/min and 150 K/min. Two multiphoton imaging systems were used: a system based on a modified optical microscope and a flexible mobile system. To illustrate the imaging capabilities, plant leafs as well as animal cells were microscopically imaged in vivo during freezing based on autofluorescence lifetime and intensity of intrinsic molecules. The measurements illustrate the usefulness of multiphoton imaging to investigate freezing effects on animal and plant cells.

  9. Comparative analysis of toxin detection in biological and enviromental samples

    Science.gov (United States)

    Ogert, Robert A.; Burans, James; O'Brien, Tom; Ligler, Frances S.

    1994-03-01

    The basic recognition schemes underlying the principles of standard enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay (RIA) protocols are increasingly being adapted for use with new detection devices. A direct comparison was made using a fiber optic biosensor that employs evanescent wave detection and an ELISA using avidin-biotin. The assays were developed for the detection of Ricinus communis agglutinin II, also known as ricin or RCA60. Detection limits between the two methods were comparable for ricin in phosphate buffered saline (PBS), however results in complex samples differed slightly. In PBS, sensitivity for ricin was 1 ng/ml using the fiber optic device and 500 pg/ml using the ELISA. The fiber optic sensor could not detect ricin directly in urine or serum spiked with 5 ng/ml ricin, however, the ELISA showed detection but at reduced levels to the PBS control.

  10. Biology, Culture and Society: An Explanation of Human Development.

    Science.gov (United States)

    Mandel, Barbara

    Traditional sociological conceptions of human group development and early human group behavior are critiqued in light of anthropological, biological, and physiological data. The objective of the study was to identify shortcomings of sociological research when non-sociological data is consistently ignored. Review of sociological studies of human…

  11. The Human Genome Project and Biology Education.

    Science.gov (United States)

    McInerney, Joseph D.

    1996-01-01

    Highlights the importance of the Human Genome Project in educating the public about genetics. Discusses four challenges that science educators must address: teaching for conceptual understanding, the nature of science, the personal and social impact of science and technology, and the principles of technology. Contains 45 references. (JRH)

  12. The biological coherence of human phenome databases.

    NARCIS (Netherlands)

    Oti, M.O.; Huynen, M.A.; Brunner, H.G.

    2009-01-01

    Disease networks are increasingly explored as a complement to networks centered around interactions between genes and proteins. The quality of disease networks is heavily dependent on the amount and quality of phenotype information in phenotype databases of human genetic diseases. We explored which

  13. The Biological Basis of Human Irrationality.

    Science.gov (United States)

    Ellis, Albert

    If we define irrationality as thought, emotion, or behavior that leads to self-defeating consequences or that significantly interferes with the survival and happiness of the organism, we find that literally hundreds of major irrationalities exist in all societies and in virtually all humans in those societies. These irrationalities persist despite…

  14. Synthetic Biology and Human Health: Potential Applications for Spaceflight

    Science.gov (United States)

    Karouia, Fathi; Carr, Christopher; Cai, Yizhi; Chen, Y.; Grenon, Marlene; Larios-Sanz, Maia; Jones, Jeffrey A.; Santos, Orlando

    2011-01-01

    Human space travelers experience a unique environment that affects homeostasis and physiologic adaptation. Spaceflight-related changes have been reported in the musculo-skeletal, cardiovascular, neurovestibular, endocrine, and immune systems. The spacecraft environment further subjects the traveler to noise and gravitational forces, as well as airborne chemical, microbiological contaminants, and radiation exposure. As humans prepare for longer duration missions effective countermeasures must be developed, verified, and implemented to ensure mission success. Over the past ten years, synthetic biology has opened new avenues for research and development in areas such as biological control, biomaterials, sustainable energy production, bioremediation, and biomedical therapies. The latter in particular is of great interest to the implementation of long-duration human spaceflight capabilities. This article discusses the effects of spaceflight on humans, and reviews current capabilities and potential needs associated with the health of the astronauts where synthetic biology could play an important role in the pursuit of space exploration.

  15. Principles of Security: Human, Cyber, and Biological

    CERN Document Server

    Stacey, Blake C

    2013-01-01

    Cybersecurity attacks are a major and increasing burden to economic and social systems globally. Here we analyze the principles of security in different domains and demonstrate an architectural flaw in current cybersecurity. Cybersecurity is inherently weak because it is missing the ability to defend the overall system instead of individual computers. The current architecture enables all nodes in the computer network to communicate transparently with one another, so security would require protecting every computer in the network from all possible attacks. In contrast, other systems depend on system-wide protections. In providing conventional security, police patrol neighborhoods and the military secures borders, rather than defending each individual household. Likewise, in biology, the immune system provides security against viruses and bacteria using primarily action at the skin, membranes, and blood, rather than requiring each cell to defend itself. We propose applying these same principles to address the c...

  16. Molecular biology of human muscle disease

    Energy Technology Data Exchange (ETDEWEB)

    Dunne, P.W.; Epstein, H.F. (Baylor Coll. of Medicine, Houston, TX (United States))

    1991-01-01

    The molecular revolution that is transforming the entire biomedical field has had far-reaching impact in its application to inherited human muscle disease. The gene for Duchenne muscular dystrophy was one of the first cloned without knowledge of the defective protein product. This success was based upon the availability of key chromosomal aberrations that provided molecular landmarks for the disease locus. Subsequent discoveries regarding the mode of expression for this gene, the structure and localization of its protein product dystrophin, and molecular diagnosis of affected and carrier individuals constitute a paradigm for investigation of human genetics. Finding the gene for myotonic muscular dystrophy is requiring the brute force approach of cloning several million bases of DNA, identifying expressed sequences, and characterizing candidate genes. The gene that causes hypertrophic cardiomyopathy has been found serendipitously to be one of the genetic markers on chromosome 14, the {beta} myosin heavy chain.

  17. Standard reporting requirements for biological samples in metabolomics experiments: Microbial and in vitro biology experiments

    NARCIS (Netherlands)

    Werf, M.J. van der; Takors, R.; Smedsgaard, J.; Nielsen, J.; Ferenci, T.; Portais, J.C.; Wittmann, C.; Hooks, M.; Tomassini, A.; Oldiges, M.; Fostel, J.; Sauer, U.

    2007-01-01

    With the increasing use of metabolomics as a means to study a large number of different biological research questions, there is a need for a minimal set of reporting standards that allow the scientific community to evaluate, understand, repeat, compare and re-investigate metabolomics studies. Here w

  18. Isolation of Campylobacter from human stool samples

    Directory of Open Access Journals (Sweden)

    S M Salim

    2014-01-01

    Full Text Available Context: Campylobacter is an undetected cause of diarrhoea especially under 5 years of age in most of the countries. Isolation of this organism is difficult, expensive and cumbersome. Aims: Our objective of this study was to isolate this pathogen from the stool specimens on routinely available blood containing laboratory media using the candle jar for creating the microaerophilic atmosphere in our setup. Settings and Designs: A descriptive study. Materials and Methods: A total of 50 stool samples were inoculated onto selective and non-selective media with and without filtration using a 0.45 μm membrane. The inoculated media were simultaneously incubated in microaerophilic conditions using the Anoxomat as well as in candle jars at temperatures 37°C and 42°C. The culture isolates were confirmed by standard phenotypic tests. A simplex polymerase chain reaction (PCR targeting the 16S ribosomal deoxyribonucleic acid of Campylobacter was performed on the deoxyribonucleic acid (DNA of the culture isolates as well as on the DNA extracted from the stool filtrates. Statistical Analysis: Data was expressed as a proportion. Results: Campylobacter could be isolated in 5 out of 50 stool samples using both the Anoxomat as well as the candle jar. Furthermore, we did not find any difference between the isolation using the selective and blood containing media as well as the different incubation temperatures. All the five were confirmed phenotypically and genotypically to be Campylobacter jejuni. The PCR results corroborated with that of the culture. Conclusions: Isolation by culture was as sensitive as that of the PCR.

  19. Ultrasensitive techniques for measurement of uranium in biological samples and the nephrotoxicity of uranium: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Kathren, R.L.; Weber, J.R. (eds.)

    1988-04-01

    Edited transcripts are provided of two public meetings sponsored by the Division of Radiation Programs and Earth Sciences of the Nuclear Regulatory Commission, Occupational Radiation Protection Branch. The first meeting, held on December 3, 1985, included nine presentations covering ultrasensitive techniques for measurement of uranium in biological specimens. Topics included laser-spectrometric techniques for uranium bioassay, correlation of urinary uranium samples with air sampling results in industrial settings, delayed neutron counting, laser-kinetic phosphometry, isotope dilution mass spectrometry, resonance ionization spectroscopy, fission track analysis, laser-induced fluorescence, and costs of sampling and processing. The nine presentations of the second meeting dealt with the nephrotoxicity of uranium. Among the topics presented were the physiology of the kidney, the effects of heavy metals on the kidney, animal studies in uranium nephrotoxicity, comparisons of kidney histology in nine humans, renal effects in uranium mill workers, renal damage from different uranium isotopes, and Canadian studies on uranium toxicity. Discussions following the presentations are included in the edited transcripts. 30 refs., 9 figs., 9 tabs.

  20. The biology of human sexuality: evolution, ecology and physiology

    Directory of Open Access Journals (Sweden)

    PW Bateman

    2006-09-01

    Full Text Available Many evolutionary biologists argue that human sexual behaviour can be studied in exactly the same way as that of other species. Many sociologists argue that social influences effectively obscure, and are more important than, a reductionist biological approach to human sexual behaviour. Here,we authors attempt to provide a broad introduction to human sexual behaviour from a biological standpoint and to indicate where the ambiguous areas are. We outline the evolutionary selective pressures that are likely to have influenced human behaviour and mate choice in the past and in the present; ecological features that influence such things as degree of parental care and polygamy; and the associated physiology of human sexuality. Then they end with a discussion of �abnormal� sexuality.

  1. Robotic, MEMS-based Multi Utility Sample Preparation Instrument for ISS Biological Workstation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop a multi-functional, automated sample preparation instrument for biological wet-lab workstations on the ISS. The instrument is based on a...

  2. Proteomic biomarker discovery in 1000 human plasma samples with mass spectrometry

    DEFF Research Database (Denmark)

    Cominetti, Ornella; Núñez Galindo, Antonio; Corthésy, John

    2016-01-01

    the quality of the MS data and provided descriptive statistics. The data set was interrogated for proteins with most stable expression levels in that set of plasma samples. We evaluated standard clinical variables that typically impact forthcoming results and assessed body mass index-associated and gender......-specific proteins at two time points. We demonstrate that analyzing a large number of human plasma samples for biomarker discovery with MS using isobaric tagging is feasible, providing robust and consistent biological results....

  3. Detection of heavy metals in biological samples through anodic stripping voltammetry

    OpenAIRE

    Buzea, Vlad; Florescu, Monica; Badea, Mihaela

    2012-01-01

    The toxicological aspects due to the presence of heavy metals in biological samples impose to have accurate and rapid methods for their detection. This paper is aimed to review approaches to anodic stripping voltammetry (ASV) determination of several heavy metals (lead, cadmium, copper, mercury, zinc) in biological matrices (blood, urine, saliva, tissue sample). Analytical performances (LOD, data linearity range, sensitivity) of the reviewed methods were presented for several electrochemical ...

  4. Optimization of techniques for multiple platform testing in small, precious samples such as human chorionic villus sampling.

    Science.gov (United States)

    Pisarska, Margareta D; Akhlaghpour, Marzieh; Lee, Bora; Barlow, Gillian M; Xu, Ning; Wang, Erica T; Mackey, Aaron J; Farber, Charles R; Rich, Stephen S; Rotter, Jerome I; Chen, Yii-der I; Goodarzi, Mark O; Guller, Seth; Williams, John

    2016-11-01

    Multiple testing to understand global changes in gene expression based on genetic and epigenetic modifications is evolving. Chorionic villi, obtained for prenatal testing, is limited, but can be used to understand ongoing human pregnancies. However, optimal storage, processing and utilization of CVS for multiple platform testing have not been established. Leftover CVS samples were flash-frozen or preserved in RNAlater. Modifications to standard isolation kits were performed to isolate quality DNA and RNA from samples as small as 2-5 mg. RNAlater samples had significantly higher RNA yields and quality and were successfully used in microarray and RNA-sequencing (RNA-seq). RNA-seq libraries generated using 200 versus 800-ng RNA showed similar biological coefficients of variation. RNAlater samples had lower DNA yields and quality, which improved by heating the elution buffer to 70 °C. Purification of DNA was not necessary for bisulfite-conversion and genome-wide methylation profiling. CVS cells were propagated and continue to express genes found in freshly isolated chorionic villi. CVS samples preserved in RNAlater are superior. Our optimized techniques provide specimens for genetic, epigenetic and gene expression studies from a single small sample which can be used to develop diagnostics and treatments using a systems biology approach in the prenatal period. © 2016 John Wiley & Sons, Ltd. © 2016 John Wiley & Sons, Ltd.

  5. Human biological monitoring of suspected endocrine-disrupting compounds

    Directory of Open Access Journals (Sweden)

    Moosa Faniband

    2014-02-01

    Full Text Available Endocrine-disrupting compounds are exogenous agents that interfere with the natural hormones of the body. Human biological monitoring is a powerful method for monitoring exposure to endocrine disrupting compounds. In this review, we describe human biological monitoring systems for different groups of endocrine disrupting compounds, polychlorinated biphenyls, brominated flame retardants, phthalates, alkylphenols, pesticides, metals, perfluronated compounds, parabens, ultraviolet filters, and organic solvents. The aspects discussed are origin to exposure, metabolism, matrices to analyse, analytical determination methods, determinants, and time trends.

  6. Sample preparation strategies for food and biological samples prior to nanoparticle detection and imaging

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Löschner, Katrin

    2014-01-01

    fractionation (AFFF, or AF4) coupled on-line to various detectors including static and dynamic light scattering (LS), UV or fluorescence (FL) spectroscopies and ICP-MS have proven useful and powerful [1, 2, 3]. Furthermore, additional information obtained by an imaging method such as transmission electron...... microscopy (TEM) proved to be necessary for trouble shooting of results obtained from AFFF-LS-ICP-MS. Aqueous and enzymatic extraction strategies were tested for thorough sample preparation aiming at degrading the sample matrix and to liberate the AgNPs from chicken meat into liquid suspension. The resulting...

  7. Estimation of copper and iron burden in biological samples of various stages of hepatitis C and liver cirrhosis patients.

    Science.gov (United States)

    Arain, Salma Aslam; Kazi, Tasneem G; Afridi, Hassan Imran; Talpur, Farah Naz; Mughal, Moina Akhtar; Shah, Faheem; Arain, Sadaf Sadia; Panhwar, Abdul Haleem

    2014-08-01

    There is accumulative evidence that the metabolism of iron (Fe) and copper (Cu) is altered in human due to infections, indicating that both elements have roles in pathogenesis and progress of viral diseases. In the present study, the correlation of Cu and Fe was evaluate in biological samples (serum and scalp hair) of hepatitis C (hepatitis C virus (HCV)) patients of both genders at different stages. For comparative study, the scalp hair and serum samples of healthy individuals of same age group (30-50 years) and socioeconomic status were collected. The biological samples were analyzed for Fe and Cu by atomic absorption spectroscopy after microwave-assisted acid digestion. The validity and accuracy of methodology were checked by certified reference materials of same matrixes. The levels of Cu and Fe in biological samples were enhanced in hepatic disorder patients, including acute (after diagnosis test, anti-HCV sero-positive) hepatic fibrosis and liver cirrhosis as compared to healthy referents. The difference was significant (p  0.1) except in the first stage of HCV (p human body seems to contribute to the development of cirrhosis in patients with viral hepatitis C.

  8. Electromagnetic field induced biological effects in humans.

    Science.gov (United States)

    Kaszuba-Zwoińska, Jolanta; Gremba, Jerzy; Gałdzińska-Calik, Barbara; Wójcik-Piotrowicz, Karolina; Thor, Piotr J

    2015-01-01

    Exposure to artificial radio frequency electromagnetic fields (EMFs) has increased significantly in recent decades. Therefore, there is a growing scientific and social interest in its influence on health, even upon exposure significantly below the applicable standards. The intensity of electromagnetic radiation in human environment is increasing and currently reaches astronomical levels that had never before experienced on our planet. The most influential process of EMF impact on living organisms, is its direct tissue penetration. The current established standards of exposure to EMFs in Poland and in the rest of the world are based on the thermal effect. It is well known that weak EMF could cause all sorts of dramatic non-thermal effects in body cells, tissues and organs. The observed symptoms are hardly to assign to other environmental factors occurring simultaneously in the human environment. Although, there are still ongoing discussions on non-thermal effects of EMF influence, on May 31, 2011--International Agency for Research on Cancer (IARC)--Agenda of World Health Organization (WHO) has classified radio electromagnetic fields, to a category 2B as potentially carcinogenic. Electromagnetic fields can be dangerous not only because of the risk of cancer, but also other health problems, including electromagnetic hypersensitivity (EHS). Electromagnetic hypersensitivity (EHS) is a phenomenon characterized by the appearance of symptoms after exposure of people to electromagnetic fields, generated by EHS is characterized as a syndrome with a broad spectrum of non-specific multiple organ symptoms including both acute and chronic inflammatory processes located mainly in the skin and nervous systems, as well as in respiratory, cardiovascular systems, and musculoskeletal system. WHO does not consider the EHS as a disease-- defined on the basis of medical diagnosis and symptoms associated with any known syndrome. The symptoms may be associated with a single source of EMF

  9. 37 CFR 1.775 - Calculation of patent term extension for a human drug, antibiotic drug or human biological product.

    Science.gov (United States)

    2010-07-01

    ... extension for a human drug, antibiotic drug or human biological product. 1.775 Section 1.775 Patents... drug or human biological product is eligible for extension, the term shall be extended by the time as... term of the patent for a human drug, antibiotic drug or human biological product will be extended...

  10. Microfluidic devices for sample clean-up and screening of biological samples

    NARCIS (Netherlands)

    Tetala, K.K.R.

    2009-01-01

    Analytical chemistry plays an important role in the separation and identification of analytes from raw samples (e.g. plant extracts, blood), but the whole analytical process is tedious, difficult to automate and time consuming. To overcome these drawbacks, the concept of μTAS (miniaturized total ana

  11. Microfluidic devices for sample clean-up and screening of biological samples

    NARCIS (Netherlands)

    Tetala, K.K.R.

    2009-01-01

    Analytical chemistry plays an important role in the separation and identification of analytes from raw samples (e.g. plant extracts, blood), but the whole analytical process is tedious, difficult to automate and time consuming. To overcome these drawbacks, the concept of μTAS (miniaturized total ana

  12. Improving human forensics through advances in genetics, genomics and molecular biology.

    Science.gov (United States)

    Kayser, Manfred; de Knijff, Peter

    2011-03-01

    Forensic DNA profiling currently allows the identification of persons already known to investigating authorities. Recent advances have produced new types of genetic markers with the potential to overcome some important limitations of current DNA profiling methods. Moreover, other developments are enabling completely new kinds of forensically relevant information to be extracted from biological samples. These include new molecular approaches for finding individuals previously unknown to investigators, and new molecular methods to support links between forensic sample donors and criminal acts. Such advances in genetics, genomics and molecular biology are likely to improve human forensic case work in the near future.

  13. Application of ion mobility spectrometry for the determination of tramadol in biological samples

    Directory of Open Access Journals (Sweden)

    Ali Sheibani

    2014-12-01

    Full Text Available In this study, a simple and rapid ion mobility spectrometry (IMS method has been described for the determination of tramadol. The operating instrumental parameters that could influence IMS were investigated and optimized (temperature; injection: 220 and IMS cell: 190°C, flow rate; carrier: 300 and drift: 600 mL/minute, voltage; corona: 2300 and drift: 7000 V, pulse width: 100 μs. Under optimum conditions, the calibration curves were linear within two orders of magnitude with R2 ≥ 0.998 for the determination of tramadol in human plasma, saliva, serum, and urine samples. The limits of detection and the limits of quantitation were between 0.1 and 0.3 and 0.3 and 1 ng/mL, respectively. The relative standard deviations were between 7.5 and 8.8%. The recovery results (90–103.9% indicate that the proposed method can be applied for tramadol analysis in different biological samples.

  14. Development of Sampling and Preservation Techniques to Retard Chemical and Biological Changes in Water Samples

    Science.gov (United States)

    1983-06-24

    accomplishing the original scope of work (development of sampling and pres- ervation techniques). System No. I is described in Table 1. Quadruplicate SARM ...Rate: 1.0 ml/min Injection Volume: 40-100 p1 Quadruplicate SARM reference solutions were analyzed for the four munitions at the following concentration...tion of SARM Reference Solutions of DNP, RDX, TNBI DNB, 2,4-DNT, TNT, Tetryl, and DPA ...... .............. A-6 2 Statistical Evaluation of DNP in

  15. The DNA-damage response in human biology and disease

    DEFF Research Database (Denmark)

    Jackson, Stephen P; Bartek, Jiri

    2009-01-01

    , signal its presence and mediate its repair. Such responses, which have an impact on a wide range of cellular events, are biologically significant because they prevent diverse human diseases. Our improving understanding of DNA-damage responses is providing new avenues for disease management....

  16. Human mesenchymal stromal cells : biological characterization and clinical application

    NARCIS (Netherlands)

    Bernardo, Maria Ester

    2010-01-01

    This thesis focuses on the characterization of the biological and functional properties of human mesenchymal stromal cells (MSCs), isolated from different tissue sources. The differentiation capacity of MSCs from fetal and adult tissues has been tested and compared. Umbilical cord blood (UCB) has be

  17. Applied Developmental Biology: Making Human Pancreatic Beta Cells for Diabetics.

    Science.gov (United States)

    Melton, Douglas A

    2016-01-01

    Understanding the genes and signaling pathways that determine the differentiation and fate of a cell is a central goal of developmental biology. Using that information to gain mastery over the fates of cells presents new approaches to cell transplantation and drug discovery for human diseases including diabetes. © 2016 Elsevier Inc. All rights reserved.

  18. Enhancing Biology Instruction with the Human Genome Project

    Science.gov (United States)

    Buxeda, Rosa J.; Moore-Russo, Deborah A.

    2003-01-01

    The Human Genome Project (HGP) is a recent scientific milestone that has received notable attention. This article shows how a biology course is using the HGP to enhance students' experiences by providing awareness of cutting edge research, with information on new emerging career options, and with opportunities to consider ethical questions raised…

  19. The Human Genome Project: Biology, Computers, and Privacy.

    Science.gov (United States)

    Cutter, Mary Ann G.; Drexler, Edward; Gottesman, Kay S.; Goulding, Philip G.; McCullough, Laurence B.; McInerney, Joseph D.; Micikas, Lynda B.; Mural, Richard J.; Murray, Jeffrey C.; Zola, John

    This module, for high school teachers, is the second of two modules about the Human Genome Project (HGP) produced by the Biological Sciences Curriculum Study (BSCS). The first section of this module provides background information for teachers about the structure and objectives of the HGP, aspects of the science and technology that underlie the…

  20. Teacher's Study Guide on the Biology of Human Populations: Asia.

    Science.gov (United States)

    United Nations Educational, Scientific, and Cultural Organization, Paris (France).

    Factual and conceptual information dealing with the biology of human populations is offered in this guide for secondary science teachers. Instructional approaches are reviewed and suggestions are offered for use of the problem method approach, the discussion technique, and the project option. Information is organized into an introduction and five…

  1. Study of complex matrix effect on solid phase microextraction for biological sample analysis.

    Science.gov (United States)

    Jiang, Ruifen; Xu, Jianqiao; Zhu, Fang; Luan, Tiangang; Zeng, Feng; Shen, Yong; Ouyang, Gangfeng

    2015-09-11

    Solid phase microextraction (SPME) has become a useful tool for in vivo monitoring the behavior of environmental organic pollutants in biological species due to its simplicity, relatively non-invasive, and cost-effective manner. However, the complex matrices in biological samples could significantly influence the extraction kinetic, and bias the quantification result. In this study, we investigated the effect of complex matrix on the extraction kinetic of SPME for biological sample analysis. Two sample matrices, phosphate-buffered saline (PBS) with bovine serum albumin (BSA) and agarose gel with BSA were used to simulate the biological fluid and tissue. Results showed that the addition of BSA significantly enhanced the mass transfer of organic compounds onto SPME fiber in both PBS buffer and gel sample. Enhancement factors ranging from 1.3 to 27, and 2.0 to 80 were found for all selected polyaromatic hydrocarbons (PAHs) in PBS buffer and agarose gel with BSA concentration of 0.1-5%, respectively. Then, an improved theoretical model was applied to quantify the observed enhancement effect, and the result showed that the predicted sampling time constant agreed well with the experimental one in complex matrix. Furthermore, a simplified equation was proposed for the real biological sample analysis.

  2. Estimation of calcium, magnesium, cadmium, and lead in biological samples from paralyzed quality control and production steel mill workers.

    Science.gov (United States)

    Afridi, Hassan Imran; Talpur, Farah Naz; Kazi, Tasneem Gul; Kazi, Naveed; Arain, Sadaf Sadia; Shah, Faheem

    2015-06-01

    The determination of trace and toxic metals in the biological samples of human beings is an important clinical screening procedure. The aim of the present study was to compare the level of essential trace and toxic elements cadmium (Cd), calcium (Ca), lead (Pb), and magnesium (Mg) in biological samples (whole blood, urine, and scalp hair) of male paralyzed production (PPW) and quality control workers (PQW) of a steel mill, age ranged (35-55 years). For comparison purposes, healthy age-matched exposed referent subjects (EC), working in steel mill and control subjects (NEC), who were not working in industries and lived far away from the industrial areas, were selected as control subjects. The concentrations of electrolytes and toxic elements in biological samples were measured by atomic absorption spectrometry after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference materials. The results of this study showed that the mean values of Cd and Pb were significantly higher in scalp hair, blood, and urine samples of PPW and PQW as compared to NEC and EC (p urine samples of PPW and PQW. The results show the need for immediate improvements in workplace, ventilation, and industrial hygiene practices.

  3. Human Metabolic Network: Reconstruction, Simulation, and Applications in Systems Biology

    Science.gov (United States)

    Wu, Ming; Chan, Christina

    2012-01-01

    Metabolism is crucial to cell growth and proliferation. Deficiency or alterations in metabolic functions are known to be involved in many human diseases. Therefore, understanding the human metabolic system is important for the study and treatment of complex diseases. Current reconstructions of the global human metabolic network provide a computational platform to integrate genome-scale information on metabolism. The platform enables a systematic study of the regulation and is applicable to a wide variety of cases, wherein one could rely on in silico perturbations to predict novel targets, interpret systemic effects, and identify alterations in the metabolic states to better understand the genotype-phenotype relationships. In this review, we describe the reconstruction of the human metabolic network, introduce the constraint based modeling approach to analyze metabolic networks, and discuss systems biology applications to study human physiology and pathology. We highlight the challenges and opportunities in network reconstruction and systems modeling of the human metabolic system. PMID:24957377

  4. Determination of Cu, Zn, and Se in microvolumes of liquid biological samples

    Science.gov (United States)

    Shaban, H. A.; Shaltout, A. A.; Abdou, M.; Al Ashker, E. A.; Elgohary, M.

    2011-01-01

    Cu, Zn, and Se were successfully determined in a few microliters (<100 μl) of biological samples using discrete injection atomic absorption spectrometry. Different factors were investigated in order to obtain a biological sample volume which is valid for analysis. Among them are the effect of microsampling volume variations (starting from 40 to 200 μl), nebulization efficiency, detection limits, precision, and finally the calibration and sensitivity of the proposed method. It was found that 60 μl of the biological sample was adequate for the quantitative analysis with reasonable precision. The advantages of the proposed method are not only rapidity, simplicity, sensitivity, and good precision, but also, contrary to conventional flame atomic absorption spectrometry, the capability of analyzing microvolumes of samples.

  5. Non-destructive electron microscopy imaging and analysis of biological samples with graphene coating

    Science.gov (United States)

    Park, Jong Bo; Kim, Yong-Jin; Kim, Seong-Min; Yoo, Je Min; Kim, Youngsoo; Gorbachev, Roman; Barbolina, I. I.; Kim, Sang Jin; Kang, Sangmin; Yoon, Myung-Han; Cho, Sung-Pyo; Novoselov, Konstantin S.; Hong, Byung Hee

    2016-12-01

    In electron microscopy (EM), charging of non-conductive biological samples by focused electron beams hinders their high-resolution imaging. Gold or platinum coatings have been commonly used to prevent such sample charging, but it disables further quantitative and qualitative chemical analyses such as energy dispersive spectroscopy (EDS). Here we report that graphene-coating on biological samples enables non-destructive high-resolution imaging by EM as well as chemical analysis by EDS, utilizing graphene’s transparency to electron beams, high conductivity, outstanding mechanical strength and flexibility. We believe that the graphene-coated imaging and analysis would provide us a new opportunity to explore various biological phenomena unseen before due to the limitation in sample preparation and image resolution, which will broaden our understanding on the life mechanism of various living organisms.

  6. Quantitating morphological changes in biological samples during scanning electron microscopy sample preparation with correlative super-resolution microscopy.

    Science.gov (United States)

    Zhang, Ying; Huang, Tao; Jorgens, Danielle M; Nickerson, Andrew; Lin, Li-Jung; Pelz, Joshua; Gray, Joe W; López, Claudia S; Nan, Xiaolin

    2017-01-01

    Sample preparation is critical to biological electron microscopy (EM), and there have been continuous efforts on optimizing the procedures to best preserve structures of interest in the sample. However, a quantitative characterization of the morphological changes associated with each step in EM sample preparation is currently lacking. Using correlative EM and superresolution microscopy (SRM), we have examined the effects of different drying methods as well as osmium tetroxide (OsO4) post-fixation on cell morphology during scanning electron microscopy (SEM) sample preparation. Here, SRM images of the sample acquired under hydrated conditions were used as a baseline for evaluating morphological changes as the sample went through SEM sample processing. We found that both chemical drying and critical point drying lead to a mild cellular boundary retraction of ~60 nm. Post-fixation by OsO4 causes at least 40 nm additional boundary retraction. We also found that coating coverslips with adhesion molecules such as fibronectin prior to cell plating helps reduce cell distortion from OsO4 post-fixation. These quantitative measurements offer useful information for identifying causes of cell distortions in SEM sample preparation and improving current procedures.

  7. Calcium isolation from large-volume human urine samples for 41Ca analysis by accelerator mass spectrometry.

    Science.gov (United States)

    Miller, James J; Hui, Susanta K; Jackson, George S; Clark, Sara P; Einstein, Jane; Weaver, Connie M; Bhattacharyya, Maryka H

    2013-08-01

    Calcium oxalate precipitation is the first step in preparation of biological samples for (41)Ca analysis by accelerator mass spectrometry. A simplified protocol for large-volume human urine samples was characterized, with statistically significant increases in ion current and decreases in interference. This large-volume assay minimizes cost and effort and maximizes time after (41)Ca administration during which human samples, collected over a lifetime, provide (41)Ca:Ca ratios that are significantly above background.

  8. Calcium Isolation from Large-Volume Human Urine Samples for 41Ca Analysis by Accelerator Mass Spectrometry

    Science.gov (United States)

    Miller, James J; Hui, Susanta K; Jackson, George S; Clark, Sara P; Einstein, Jane; Weaver, Connie M; Bhattacharyya, Maryka H

    2013-01-01

    Calcium oxalate precipitation is the first step in preparation of biological samples for 41Ca analysis by accelerator mass spectrometry. A simplified protocol for large-volume human urine samples was characterized, with statistically significant increases in ion current and decreases in interference. This large-volume assay minimizes cost and effort and maximizes time after 41Ca administration during which human samples, collected over a lifetime, provide 41Ca:Ca ratios that are significantly above background. PMID:23672965

  9. The human premotor cortex is 'mirror' only for biological actions.

    Science.gov (United States)

    Tai, Yen F; Scherfler, Christoph; Brooks, David J; Sawamoto, Nobukatsu; Castiello, Umberto

    2004-01-20

    Previous work has shown that both human adults and children attend to grasping actions performed by another person but not necessarily to those made by a mechanical device. According to recent neurophysiological data, the monkey premotor cortex contains "mirror" neurons that discharge both when the monkey performs specific manual grasping actions and when it observes another individual performing the same or similar actions. However, when a human model uses tools to perform grasping actions, the mirror neurons are not activated. A similar "mirror" system has been described in humans, but whether or not it is also tuned specifically to biological actions has never been tested. Here we show that when subjects observed manual grasping actions performed by a human model a significant neural response was elicited in the left premotor cortex. This activation was not evident for the observation of grasping actions performed by a robot model commanded by an experimenter. This result indicates for the first time that in humans the mirror system is biologically tuned. This system appears to be the neural substrate for biological preference during action coding.

  10. Membrane materials for storing biological samples intended for comparative nanotoxicological testing

    Science.gov (United States)

    Metelkin, A.; Kuznetsov, D.; Kolesnikov, E.; Chuprunov, K.; Kondakov, S.; Osipov, A.; Samsonova, J.

    2015-11-01

    The study is aimed at identifying the samples of most promising membrane materials for storing dry specimens of biological fluids (Dried Blood Spots, DBS technology). Existing sampling systems using cellulose fiber filter paper have a number of drawbacks such as uneven distribution of the sample spot, dependence of the spot spreading area on the individual biosample properties, incomplete washing-off of the sample due to partially inconvertible sorption of blood components on cellulose fibers, etc. Samples of membrane materials based on cellulose, polymers and glass fiber with applied biosamples were studied using methods of scanning electron microscopy, FT-IR spectroscopy and surface-wetting measurement. It was discovered that cellulose-based membrane materials sorb components of biological fluids inside their structure, while membranes based on glass fiber display almost no interaction with the samples and biological fluid components dry to films in the membrane pores between the structural fibers. This characteristic, together with the fact that membrane materials based on glass fiber possess sufficient strength, high wetting properties and good storage capacity, attests them as promising material for dry samples of biological fluids storage systems.

  11. Electromembrane extraction as a rapid and selective miniaturized sample preparation technique for biological fluids

    DEFF Research Database (Denmark)

    Gjelstad, Astrid; Pedersen-Bjergaard, Stig; Seip, Knut Fredrik

    2015-01-01

    This special report discusses the sample preparation method electromembrane extraction, which was introduced in 2006 as a rapid and selective miniaturized extraction method. The extraction principle is based on isolation of charged analytes extracted from an aqueous sample, across a thin film....... Technical aspects of electromembrane extraction, important extraction parameters as well as a handful of examples of applications from different biological samples and bioanalytical areas are discussed in the paper....

  12. Chemometric and Statistical Analyses of ToF-SIMS Spectra of Increasingly Complex Biological Samples

    Energy Technology Data Exchange (ETDEWEB)

    Berman, E S; Wu, L; Fortson, S L; Nelson, D O; Kulp, K S; Wu, K J

    2007-10-24

    Characterizing and classifying molecular variation within biological samples is critical for determining fundamental mechanisms of biological processes that will lead to new insights including improved disease understanding. Towards these ends, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to examine increasingly complex samples of biological relevance, including monosaccharide isomers, pure proteins, complex protein mixtures, and mouse embryo tissues. The complex mass spectral data sets produced were analyzed using five common statistical and chemometric multivariate analysis techniques: principal component analysis (PCA), linear discriminant analysis (LDA), partial least squares discriminant analysis (PLSDA), soft independent modeling of class analogy (SIMCA), and decision tree analysis by recursive partitioning. PCA was found to be a valuable first step in multivariate analysis, providing insight both into the relative groupings of samples and into the molecular basis for those groupings. For the monosaccharides, pure proteins and protein mixture samples, all of LDA, PLSDA, and SIMCA were found to produce excellent classification given a sufficient number of compound variables calculated. For the mouse embryo tissues, however, SIMCA did not produce as accurate a classification. The decision tree analysis was found to be the least successful for all the data sets, providing neither as accurate a classification nor chemical insight for any of the tested samples. Based on these results we conclude that as the complexity of the sample increases, so must the sophistication of the multivariate technique used to classify the samples. PCA is a preferred first step for understanding ToF-SIMS data that can be followed by either LDA or PLSDA for effective classification analysis. This study demonstrates the strength of ToF-SIMS combined with multivariate statistical and chemometric techniques to classify increasingly complex biological samples

  13. Correlation of mRNA and protein in complex biological samples.

    Science.gov (United States)

    Maier, Tobias; Güell, Marc; Serrano, Luis

    2009-12-17

    The correlation between mRNA and protein abundances in the cell has been reported to be notoriously poor. Recent technological advances in the quantitative analysis of mRNA and protein species in complex samples allow the detailed analysis of this pathway at the center of biological systems. We give an overview of available methods for the identification and quantification of free and ribosome-bound mRNA, protein abundances and individual protein turnover rates. We review available literature on the correlation of mRNA and protein abundances and discuss biological and technical parameters influencing the correlation of these central biological molecules.

  14. Recent developments in fatty acids profile determination in biological samples - a review

    Directory of Open Access Journals (Sweden)

    Tiuca Ioana

    2015-12-01

    Full Text Available The present paper is a literature review of the recent years dealing with the most important separation techniques of fatty acids in biological samples. Our aim was to make a synthesis of the analytical methods used, to note the most used ones, but also to mention other methods that are less utilized, which can have important advantages (such as less time consuming, greener reagents, etc.. Gas-chromatographic separation methods were described and compared to liquid chromatographic separations of fatty acids in different types of biological samples. In the same time, the importance of determining fatty acids profiles in biological samples was revealed, pointing out the possible implications in diagnostics of different types of disorders or remarking different profiles compared to healthy states.

  15. JURISPRUDENTIAL EXAMINATION REGARDING BIOLOGICAL SAMPLING IN THE CASE OF CONVICTED PERSONS

    Directory of Open Access Journals (Sweden)

    Gabriela\tNEMŢOI

    2015-12-01

    Full Text Available Objectives: The research devotes particular attention to the timing of biological sampling in the case of convicted persons. The main idea of the research is the factual situation regarding the criminal case law, which is not unified; problematic that prevents the formation of the National System of Judicial Genetic Data. Materials and Methods: The study focuses on evaluating the two opinions of jurisprudence on the implementation of the text of the law (Law no. 76/2008. Results: The carried research on different cases has shown that legal text is not mandatory, but its application is arbitrary, at the discretion of the court, but, nevertheless, the biological sampling in the case of convicted persons disregards the form for penalty. Conclusions: In the context of the creation of the National System of Judicial Genetic Data is a control condition on the typology of criminal profiling, we believe that biological sampling should be a priority to ensure safety of the individual.

  16. Energy-filtered transmission electron microscopy of biological samples on highly transparent carbon nanomembranes

    CERN Document Server

    Rhinow, Daniel; Weber, Nils-Eike; Beyer, André; Gölzhäuser, Armin; Kühlbrandt, Werner; Hampp, Norbert; Turchanin, Andrey; 10.1016/j.ultramic.2011.01.028

    2011-01-01

    Ultrathin carbon nanomembranes (CNM) comprising crosslinked biphenyl precursors have been tested as support films for energy-filtered transmission electron microscopy (EFTEM) of biological specimens. Due to their high transparency CNM are ideal substrates for electron energy loss spectroscopy (EELS) and electron spectroscopic imaging (ESI) of stained and unstained biological samples. Virtually background-free elemental maps of tobacco mosaic virus (TMV) and ferritin have been obtained from samples supported by ~ 1 nm thin CNM. Furthermore, we have tested conductive carbon nanomembranes (cCNM) comprising nanocrystalline graphene, obtained by thermal treatment of CNM, as supports for cryoEM of ice-embedded biological samples. We imaged ice-embedded TMV on cCNM and compared the results with images of ice-embedded TMV on conventional carbon film (CC), thus analyzing the gain in contrast for TMV on cCNM in a quantitative manner. In addition we have developed a method for the preparation of vitrified specimens, sus...

  17. The Human Genome Project: big science transforms biology and medicine.

    Science.gov (United States)

    Hood, Leroy; Rowen, Lee

    2013-01-01

    The Human Genome Project has transformed biology through its integrated big science approach to deciphering a reference human genome sequence along with the complete sequences of key model organisms. The project exemplifies the power, necessity and success of large, integrated, cross-disciplinary efforts - so-called 'big science' - directed towards complex major objectives. In this article, we discuss the ways in which this ambitious endeavor led to the development of novel technologies and analytical tools, and how it brought the expertise of engineers, computer scientists and mathematicians together with biologists. It established an open approach to data sharing and open-source software, thereby making the data resulting from the project accessible to all. The genome sequences of microbes, plants and animals have revolutionized many fields of science, including microbiology, virology, infectious disease and plant biology. Moreover, deeper knowledge of human sequence variation has begun to alter the practice of medicine. The Human Genome Project has inspired subsequent large-scale data acquisition initiatives such as the International HapMap Project, 1000 Genomes, and The Cancer Genome Atlas, as well as the recently announced Human Brain Project and the emerging Human Proteome Project.

  18. Energy-filtered transmission electron microscopy of biological samples on highly transparent carbon nanomembranes

    Energy Technology Data Exchange (ETDEWEB)

    Rhinow, Daniel, E-mail: daniel.rhinow@biophys.mpg.de [Max-Planck-Institute of Biophysics, Department of Structural Biology, Max-von-Laue-Strasse 3, D-60439 Frankfurt (Germany); Bueenfeld, Matthias; Weber, Nils-Eike; Beyer, Andre; Goelzhaeuser, Armin [University of Bielefeld, Department of Physics, Universitaetsstrasse 25, D-33615 Bielefeld (Germany); Kuehlbrandt, Werner [Max-Planck-Institute of Biophysics, Department of Structural Biology, Max-von-Laue-Strasse 3, D-60439 Frankfurt (Germany); Hampp, Norbert [University of Marburg, Department of Chemistry, Hans-Meerwein-Strasse, D-35032 Marburg (Germany); Turchanin, Andrey [University of Bielefeld, Department of Physics, Universitaetsstrasse 25, D-33615 Bielefeld (Germany)

    2011-04-15

    Ultrathin carbon nanomembranes (CNM) comprising crosslinked biphenyl precursors have been tested as support films for energy-filtered transmission electron microscopy (EFTEM) of biological specimens. Due to their high transparency CNM are ideal substrates for electron energy loss spectroscopy (EELS) and electron spectroscopic imaging (ESI) of stained and unstained biological samples. Virtually background-free elemental maps of tobacco mosaic virus (TMV) and ferritin have been obtained from samples supported by {approx}1 nm thin CNM. Furthermore, we have tested conductive carbon nanomembranes (cCNM) comprising nanocrystalline graphene, obtained by thermal treatment of CNM, as supports for cryoEM of ice-embedded biological samples. We imaged ice-embedded TMV on cCNM and compared the results with images of ice-embedded TMV on conventional carbon film (CC), thus analyzing the gain in contrast for TMV on cCNM in a quantitative manner. In addition we have developed a method for the preparation of vitrified specimens, suspended over the holes of a conventional holey carbon film, while backed by ultrathin cCNM. -- Research highlights: {yields} We examine ultrathin carbon nanomembranes (CNM) as supports for biological TEM. {yields} CNM comprise crosslinked biphenyl precursors. {yields} CNM supports enable background-free elemental mapping of heavy and light elements. {yields} We perform cryoEM of ice-embedded biological samples on graphene-like conductive CNM.

  19. BORRELIA BURGDORFERI DNA IN BIOLOGICAL SAMPLES FROM PATIENTS WITH SARCOIDOSIS USING THE POLYMERASE CHAIN REACTION TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    连伟; 罗慰慈

    1995-01-01

    Polymerase chain reaction (PCR) was used to detect the presence of Borretia burgdoferi DNA in biological samples from patients with sarcoidcsis. The target DNA sequence was of chromosomal origin. The amplified DNA sequence was analyzed by agarose gel electrophoresis, PAGE with silver staining, and the identity of amplified DNA was confirmed by restriction enzyme cleavage and DNA-DNA hybridlzation with a 32P-labelled probe. The assay was sensitive to fewer than two copies of B. burgdor feri genome, even in the presence of a 104-fold excess of human eukaryotic DNA, and was also specific to different B. burgdorferl strains tested. Sera seroiogieally positive to B. burgdorferi (n=26), broncbemlveolar lavage fluid and supematant of BALF (n=26) and peripheral blood (n=9) from sarcoidosis patients were tested. The positive rate was low (4/26, 2/26, and 0/9, respectively). It was considered that DNA from B. bur gdor feri may be identified in a minority of patients with s,arcoidosis, and it may play a pathogenetic rote in such cases. More studies need to be done before advancing the hypothesis of an etiologic role of B. burgdorferi in sarcoidosis.

  20. Analytical procedure for the determination of zearalenone in environmental and biological samples.

    Science.gov (United States)

    Kwaśniewska, Katarzyna; Gadzała-Kopciuch, Renata; Cendrowski, Krzysztof

    2015-01-01

    The metabolism of zearalenone (ZEA) and analytical methods for determining the presence of ZEA and its metabolites are discussed in this study. Similar to phytoestrogens, solid metaloestrogens, pharmaceuticals, and selected pesticides, ZEA is a substance that displays endocrine activity. ZEA is accumulated in living organisms, and it is capable of contaminating all trophic levels of the food chain, from grain, maize, and other crop plants to human consumers. Zearalenone has a structure similar to that of estrogen (the presence of a macrocyclic lactone ring), it has an affinity for estrogen receptors, and it competes with 17β-estradiol for binding the estrogen receptor in natural pathways. As endocrine disruptors, zearalenone and its metabolites can also contribute to carcinogenic mutations associated with female secondary sex characteristics. The determination of zearalenone and its metabolites in various matrices, first of all biological and environmental samples, poses significant problems. A variety ways of extracting and purifying zearalenone, including liquid-liquid extraction and solid-phase extraction, are described. Furthermore, it describes the possibility of applying a plurality of sensitive and specific instrumental methods, chromatographic techniques (TLC, HPLC, GC) as well as other methods (immunoaffinity chromatography).

  1. Microwave-accelerated bioassay technique for rapid and quantitative detection of biological and environmental samples.

    Science.gov (United States)

    Mohammed, Muzaffer; Syed, Maleeha F; Aslan, Kadir

    2016-01-15

    Quantitative detection of molecules of interest from biological and environmental samples in a rapid manner, particularly with a relevant concentration range, is imperative to the timely assessment of human diseases and environmental issues. In this work, we employed the microwave-accelerated bioassay (MAB) technique, which is based on the combined use of circular bioassay platforms and microwave heating, for rapid and quantitative detection of Glial Fibrillary Acidic Protein (GFAP) and Shiga like toxin (STX 1). The proof-of-principle use of the MAB technique with the circular bioassay platforms for the rapid detection of GFAP in buffer based on colorimetric and fluorescence readouts was demonstrated with a 900W kitchen microwave. We also employed the MAB technique with a new microwave system (called the iCrystal system) for the detection of GFAP from mice with brain injuries and STX 1 from a city water stream. Control bioassays included the commercially available gold standard bioassay kits run at room temperature. Our results show that the lower limit of detection (LLOD) of the colorimetric and fluorescence based bioassays for GFAP was decreased by ~1000 times using the MAB technique and our circular bioassay platforms as compared to the commercially available bioassay kits. The overall bioassay time for GFAP and STX 1 was reduced from 4h using commercially available bioassay kits to 10min using the MAB technique.

  2. Substrate-zymography: a still worthwhile method for gelatinases analysis in biological samples.

    Science.gov (United States)

    Ricci, Serena; D'Esposito, Vittoria; Oriente, Francesco; Formisano, Pietro; Di Carlo, Angelina

    2016-08-01

    Matrix metallo-proteinases (MMPs) are a family of zinc-dependent endopeptidases, capable of degrading all the molecular components of extracellular matrix. A class of MMPs is gelatinases which includes gelatinase A or MMP-2 (72 kDa) and gelatinase B or MMP-9 (92 kDa), which have been shown to play critical roles in pathophysiology of many human disease and, in particular, cancer progression. For these reasons they obtained a great interest as potential non-invasive biomarker in providing useful clinical information in cancer diagnosis and therapy. A sensitive and unexpensive method for analysis of gelatinases is the gelatine zymography, which allows to measure the relative amounts of active and inactive enzymes in body fluids and tissue extracts. The procedure involves the electrophoretic separation of proteins under denaturing but non reducing conditions through a polyacrylamide gel containing a synthetic substrate (gelatin). The aim of this mini-review has been to describe the general principles of gelatine zymography technique, underling the main advantages and disadvantages. Even though an improvement of this method is necessary for a better applicability in laboratory medicine, gelatine zymography represents the most convenient method to detect the activity of the different gelatinases from a wide range of biological samples.

  3. Approach-Induced Biases in Human Information Sampling

    Science.gov (United States)

    Hunt, Laurence T.; Rutledge, Robb B.; Malalasekera, W. M. Nishantha; Kennerley, Steven W.; Dolan, Raymond J.

    2016-01-01

    Information sampling is often biased towards seeking evidence that confirms one’s prior beliefs. Despite such biases being a pervasive feature of human behavior, their underlying causes remain unclear. Many accounts of these biases appeal to limitations of human hypothesis testing and cognition, de facto evoking notions of bounded rationality, but neglect more basic aspects of behavioral control. Here, we investigated a potential role for Pavlovian approach in biasing which information humans will choose to sample. We collected a large novel dataset from 32,445 human subjects, making over 3 million decisions, who played a gambling task designed to measure the latent causes and extent of information-sampling biases. We identified three novel approach-related biases, formalized by comparing subject behavior to a dynamic programming model of optimal information gathering. These biases reflected the amount of information sampled (“positive evidence approach”), the selection of which information to sample (“sampling the favorite”), and the interaction between information sampling and subsequent choices (“rejecting unsampled options”). The prevalence of all three biases was related to a Pavlovian approach-avoid parameter quantified within an entirely independent economic decision task. Our large dataset also revealed that individual differences in the amount of information gathered are a stable trait across multiple gameplays and can be related to demographic measures, including age and educational attainment. As well as revealing limitations in cognitive processing, our findings suggest information sampling biases reflect the expression of primitive, yet potentially ecologically adaptive, behavioral repertoires. One such behavior is sampling from options that will eventually be chosen, even when other sources of information are more pertinent for guiding future action. PMID:27832071

  4. Spectroscopic analysis of bosentan in biological samples after a liquid-liquid microextraction

    Science.gov (United States)

    Sajedi-Amin, Sanaz; Assadpour-Zeynali, Karim; Panahi-Azar, Vahid; Kebriaeezadeh, Abbas; Khoubnasabjafari, Maryam; Ansarin, Khalil; Jouyban-Gharamaleki, Vahid; Jouyban, Abolghasem

    2015-01-01

    Introduction:Microextraction processes with UV-Vis measurement have been developed and validated for analysis of bosentan in biological samples. Methods:In this work, liquid–liquid microextraction procedures (DLLME & USAEME) were employed for cleanup, pre-concentration, and determination of bosentan in biological samples by UV-Vis spectroscopy at 270 nm. The method was validated and applied to the determination of bosentan in spiked serum, exhaled breath condensate and urine samples. Results:Various experimental factors including type of extraction and dispersive solvents and their volumes, pH, sonication time and centrifuging time were investigated. Under the optimum conditions, the method was linear in the range of 1.0–5.0 μg.mL-1, with coefficient of determination (R2) of > 0.998. The limit of detection (LOD) was 0.07 mg.L-1. Recovery of the target analyte in biological samples was 106.2%. The method could be easily applied for higher concentration of bosentan and needs more improvement for application in the pharmacokinetic investigations where more sensitive methods are required. Conclusion:A simple, low cost, precise and accurate spectrophotometric analysis of bosentan in biological samples after liquid-liquid microextraction were developed and validated for routine analyses. PMID:26929923

  5. Association of environmental toxic elements in biological samples of myocardial infarction patients at different stages.

    Science.gov (United States)

    Afridi, Hassan Imran; Kazi, Tasneem Gul; Kazi, Naveed; Kandhro, Ghulam Abbas; Baig, Jameel Ahmed; Jamali, Mohammad Khan; Arain, Mohammad Balal; Shah, Abdul Qadir; Shah, Faheem; Khan, Sumaira; Kolachi, Nida Fatima

    2011-06-01

    The exposure of toxic elements may directly or indirectly associate with different pathogenesis of heart diseases. In the present study, the association of arsenic (As), cadmium (Cd), cobalt (Co), lead (Pb), and nickel (Ni) in biological samples (whole blood and urine) and mortality from myocardial infarction (MI) patients at first, second, and third heart attacks was carried out. Both biological samples of 130 MI patients (77 male and 53 female), with ages ranging from 45 to 60 years, and 61 healthy persons (33 male and 28 female) of the same age group were collected. The elements in biological samples were assessed by electrothermal atomic absorption spectrophotometer, prior to microwave-assisted acid digestion. The validity of methodology was checked by the biological certified reference materials. During this study, 78% of 32 patients aged above 50 years, registered after third MI attack, died. In these subjects, the levels of As, Cd, Co, Ni, and Pb in blood samples were higher in MI patients as compared with referents (p < 0.05), while increased by 11.7%, 12.2%, 5.55%, and 7.2%, respectively, in the blood samples of those patients who tolerated the third MI attack (p = 0.12). The high level of understudied toxic elements may play a role in the mortality of MI patients.

  6. Direct analysis of biological samples by total reflection X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Lue M, Marco P. [Unidad de Analisis Instrumental, Departamento de Quimica y Suelos, Decanato de Agronomia, Universidad Centro-occidental Lisandro Alvarado, Apartado Postal 4076, Cabudare 3023 (Venezuela)]. E-mail: luemerumarco@yahoo.es; Hernandez-Caraballo, Edwin A. [Instituto Venezolano-Andino para la Investigacion Quimica (IVAIQUIM), Facultad de Ciencias, Universidad de los Andes, Merida 5101 (Venezuela)

    2004-08-31

    The technique of total reflection X-ray fluorescence (TXRF) is well suited for the direct analysis of biological samples due to the low matrix interferences and simultaneous multi-element nature. Nevertheless, biological organic samples are frequently analysed after digestion procedures. The direct determination of analytes requires shorter analysis time, low reactive consumption and simplifies the whole analysis process. On the other hand, the biological/clinical samples are often available in minimal amounts and routine studies require the analysis of large number of samples. To overcome the difficulties associated with the analysis of organic samples, particularly of solid ones, different procedures of sample preparation and calibration to approach the direct analysis have been evaluated: (1) slurry sampling, (2) Compton peak standardization, (3) in situ microwave digestion, (4) in situ chemical modification and (5) direct analysis with internal standardization. Examples of analytical methods developed by our research group are discussed. Some of them have not been previously published, illustrating alternative strategies for coping with various problems that may be encountered in the direct analysis by total reflection X-ray fluorescence spectrometry.

  7. Putative melatonin receptors in a human biological clock

    Energy Technology Data Exchange (ETDEWEB)

    Reppert, S.M.; Weaver, D.R.; Rivkees, S.A.; Stopa, E.G.

    1988-10-07

    In vitro autoradiography with /sup 125/I-labeled melatonin was used to examine melatonin binding sites in human hypothalamus. Specific /sup 125/I-labeled melatonin binding was localized to the suprachiasmatic nuclei, the site of a putative biological clock, and was not apparent in other hypothalamic regions. Specific /sup 125/I-labeled melatonin binding was consistently found in the suprachiasmatic nuclei of hypothalami from adults and fetuses. Densitometric analysis of competition experiments with varying concentrations of melatonin showed monophasic competition curves, with comparable half-maximal inhibition values for the suprachiasmatic nuclei of adults (150 picomolar) and fetuses (110 picomolar). Micromolar concentrations of the melatonin agonist 6-chloromelatonin completely inhibited specific /sup 125/I-labeled melatonin binding, whereas the same concentrations of serotonin and norepinephrine caused only a partial reduction in specific binding. The results suggest that putative melatonin receptors are located in a human biological clock.

  8. Comparing biological motion perception in two distinct human societies.

    Directory of Open Access Journals (Sweden)

    Pierre Pica

    Full Text Available Cross cultural studies have played a pivotal role in elucidating the extent to which behavioral and mental characteristics depend on specific environmental influences. Surprisingly, little field research has been carried out on a fundamentally important perceptual ability, namely the perception of biological motion. In this report, we present details of studies carried out with the help of volunteers from the Mundurucu indigene, a group of people native to Amazonian territories in Brazil. We employed standard biological motion perception tasks inspired by over 30 years of laboratory research, in which observers attempt to decipher the walking direction of point-light (PL humans and animals. Do our effortless skills at perceiving biological activity from PL animations, as revealed in laboratory settings, generalize to people who have never before seen representational depictions of human and animal activity? The results of our studies provide a clear answer to this important, previously unanswered question. Mundurucu observers readily perceived the coherent, global shape depicted in PL walkers, and experienced the classic inversion effects that are typically found when such stimuli are turned upside down. In addition, their performance was in accord with important recent findings in the literature, in the abundant ease with which they extracted direction information from local motion invariants alone. We conclude that the effortless, veridical perception of PL biological motion is a spontaneous and universal perceptual ability, occurring both inside and outside traditional laboratory environments.

  9. Fast screening of ketamine in biological samples based on molecularly imprinted photonic hydrogels

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Liang [Department of Forensic Science, People' s Public Security University of China, Beijing (China); Meng, Pinjia, E-mail: mengpinjia@163.com [Department of Forensic Science, People' s Public Security University of China, Beijing (China); Zhang, Qingqing; Wang, Yanji [Department of Forensic Science, People' s Public Security University of China, Beijing (China)

    2013-04-10

    Graphical abstract: A novel label-free colorimetric chemosensor: with the increase in the concentration of ketamine, the Bragg diffraction peak of MIPHs gradually shifted to the longer wavelength region. Accompanying the peak shift, the color change of MIPHs was also observed obviously: from green to red. Highlights: ► We developed the label-free colorimetric MIPHs for handy and fast screening of ketamine. ► The obvious color change of MIPHs was observed upon ketamine. ► The MIPHs exhibited good sensing abilities in an aqueous environment. ► The sensing mechanisms of the water-compatible MIPHs were investigated. ► The MIPHs were employed to screening ketamine in real biological samples. -- Abstract: A novel label-free colorimetric chemosensor was developed for handy and fast screening of ketamine with high sensitivity and specificity based on molecularly imprinted photonic hydrogels (MIPHs) that combined the colloidal-crystal with molecular imprinting technique. The unique inverse opal arrays with a thin polymer wall in which the imprinted nanocavities of ketamine moleculars distributed allowed high sensitive, quick responsive, specific detection of the target analyte, and good regenerating ability in an aqueous environment. Due to the hierarchical inverse opal structural characteristics, the specific ketamine molecular recognition process can induce obvious swelling of the MIPHs to be directly transferred into visually perceptible optical signal (change in color) which can be detected by the naked eye through Bragg diffractive shifts of ordered macroporous arrays. In order to enhance the recognition ability in aqueous environments, the MIPHs were designed as water-compatible and synthesized in a water–methanol system. The molecular recognition mechanisms were investigated. The proposed MIPHs were successfully employed to screen trace level ketamine in human urine and saliva samples, exhibiting high sensitivity, rapid response, and specificity in the

  10. Linking Microbiota to Human Diseases: A Systems Biology Perspective.

    Science.gov (United States)

    Wu, Hao; Tremaroli, Valentina; Bäckhed, Fredrik

    2015-12-01

    The human gut microbiota encompasses a densely populated ecosystem that provides essential functions for host development, immune maturation, and metabolism. Alterations to the gut microbiota have been observed in numerous diseases, including human metabolic diseases such as obesity, type 2 diabetes (T2D), and irritable bowel syndrome, and some animal experiments have suggested causality. However, few studies have validated causality in humans and the underlying mechanisms remain largely to be elucidated. We discuss how systems biology approaches combined with new experimental technologies may disentangle some of the mechanistic details in the complex interactions of diet, microbiota, and host metabolism and may provide testable hypotheses for advancing our current understanding of human-microbiota interaction.

  11. Human pluripotent stem cells: an emerging model in developmental biology.

    Science.gov (United States)

    Zhu, Zengrong; Huangfu, Danwei

    2013-02-01

    Developmental biology has long benefited from studies of classic model organisms. Recently, human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, have emerged as a new model system that offers unique advantages for developmental studies. Here, we discuss how studies of hPSCs can complement classic approaches using model organisms, and how hPSCs can be used to recapitulate aspects of human embryonic development 'in a dish'. We also summarize some of the recently developed genetic tools that greatly facilitate the interrogation of gene function during hPSC differentiation. With the development of high-throughput screening technologies, hPSCs have the potential to revolutionize gene discovery in mammalian development.

  12. Salvia divinorum: toxicological aspects and analysis in human biological specimens.

    Science.gov (United States)

    Margalho, Cláudia; Corte-Real, Francisco; López-Rivadulla, Manuel; Gallardo, Eugenia

    2016-07-01

    The identification and quantitation of the main psychoactive component of Salvia divinorum (salvinorin A) in biological specimens are crucial in forensic and clinical toxicology. Despite all the efforts made, its uncontrolled abuse has increased quickly, exposing its users' health to serious risks both in the short and long term. The use of alternative biological matrices in toxicological analyzes can be advantageous as complementary postmortem samples, or in situations when neither blood nor urine can be collected; they may be useful tools in those determinations, providing important information about prior exposure. The aim of this article is to present a brief summary of legal aspects of Salvia divinorum and salvinorin A, including the methods used for the determination of the latter in biological matrices.

  13. Chronologic versus Biologic Aging of the Human Choroid

    OpenAIRE

    Christian Albrecht May

    2013-01-01

    Several aspects of chronologic and biologic aging in the human choroid are reviewed from the literature. They often reveal methodological problems for age-dependent changes of the following parameters: choroidal thickness, choroidal pigmentation, choroidal vasculature and blood flow, and choroidal innervation. On reinterpreting some data of studies concerning Bruch’s membrane, changes observed at different age points seem more likely to be nonlinear. Concluding from the data presented so far,...

  14. Novelty, Stress, and Biological Roots in Human Market Behavior

    Directory of Open Access Journals (Sweden)

    Alexey Sarapultsev

    2014-02-01

    Full Text Available Although studies examining the biological roots of human behavior have been conducted since the seminal work Kahneman and Tversky, crises and panics have not disappeared. The frequent occurrence of various types of crises has led some economists to the conviction that financial markets occasionally praise irrational judgments and that market crashes cannot be avoided a priori (Sornette 2009; Smith 2004. From a biological point of view, human behaviors are essentially the same during crises accompanied by stock market crashes and during bubble growth when share prices exceed historic highs. During those periods, most market participants see something new for themselves, and this inevitably induces a stress response in them with accompanying changes in their endocrine profiles and motivations. The result is quantitative and qualitative changes in behavior (Zhukov 2007. An underestimation of the role of novelty as a stressor is the primary shortcoming of current approaches for market research. When developing a mathematical market model, it is necessary to account for the biologically determined diphasisms of human behavior in everyday low-stress conditions and in response to stressors. This is the only type of approach that will enable forecasts of market dynamics and investor behaviors under normal conditions as well as during bubbles and panics.

  15. Novelty, stress, and biological roots in human market behavior.

    Science.gov (United States)

    Sarapultsev, Alexey; Sarapultsev, Petr

    2014-03-01

    Although studies examining the biological roots of human behavior have been conducted since the seminal work Kahneman and Tversky, crises and panics have not disappeared. The frequent occurrence of various types of crises has led some economists to the conviction that financial markets occasionally praise irrational judgments and that market crashes cannot be avoided a priori (Sornette 2009; Smith 2004). From a biological point of view, human behaviors are essentially the same during crises accompanied by stock market crashes and during bubble growth when share prices exceed historic highs. During those periods, most market participants see something new for themselves, and this inevitably induces a stress response in them with accompanying changes in their endocrine profiles and motivations. The result is quantitative and qualitative changes in behavior (Zhukov 2007). An underestimation of the role of novelty as a stressor is the primary shortcoming of current approaches for market research. When developing a mathematical market model, it is necessary to account for the biologically determined diphasisms of human behavior in everyday low-stress conditions and in response to stressors. This is the only type of approach that will enable forecasts of market dynamics and investor behaviors under normal conditions as well as during bubbles and panics.

  16. Photothermal method using a pyroelectric sensor for thermophysical characterization of agricultural and biological samples

    Science.gov (United States)

    Frandas, A.; Dadarlat, Dorin; Chirtoc, Mihai; Jalink, Henk; Bicanic, Dane D.; Paris, D.; Antoniow, Jean S.; Egee, Michel; Ungureanu, Costica

    1998-07-01

    The photopyroelectric method in different experimental configurations was used for thermophysical characterization of agricultural and biological samples. The study appears important due to the relation of thermal parameters to the quality of foodstuffs (connected to their preservation, storage and adulteration), migration profiles in biodegradable packages, and the mechanism of desiccation tolerance of seeds. Results are presented on the thermal parameters measurement and their dependence on temperature and water content for samples such as: honey, starch, seeds.

  17. Tomographic imaging of transparent biological samples using the pyramid phase microscope.

    Science.gov (United States)

    Iglesias, Ignacio

    2016-08-01

    We show how a pyramid phase microscope can be used to obtain tomographic information of the spatial variation of refractive index in biological samples using the Radon transform. A method that uses the information provided by the phase microscope for axial and lateral repositioning of the sample when it rotates is also described. Its application to the reconstruction of mouse embryos in the blastocyst stage is demonstrated.

  18. Human-Robot Site Survey and Sampling for Space Exploration

    Science.gov (United States)

    Fong, Terrence; Bualat, Maria; Edwards, Laurence; Flueckiger, Lorenzo; Kunz, Clayton; Lee, Susan Y.; Park, Eric; To, Vinh; Utz, Hans; Ackner, Nir

    2006-01-01

    NASA is planning to send humans and robots back to the Moon before 2020. In order for extended missions to be productive, high quality maps of lunar terrain and resources are required. Although orbital images can provide much information, many features (local topography, resources, etc) will have to be characterized directly on the surface. To address this need, we are developing a system to perform site survey and sampling. The system includes multiple robots and humans operating in a variety of team configurations, coordinated via peer-to-peer human-robot interaction. In this paper, we present our system design and describe planned field tests.

  19. Phytochemical analysis and biological evaluation of selected African propolis samples from Cameroon and Congo

    NARCIS (Netherlands)

    Papachroni, D.; Graikou, K.; Kosalec, I.; Damianakos, H.; Ingram, V.J.; Chinou, I.

    2015-01-01

    The objective of this study was the chemical analysis of four selected samples of African propolis (Congo and Cameroon) and their biological evaluation. Twenty-one secondary metabolites belonging to four different chemical groups were isolated from the 70% ethanolic extracts of propolis and their st

  20. Analysis of biopharmaceutical proteins in biological matrices by LC-MS/MS I. Sample preparation

    NARCIS (Netherlands)

    Bischoff, Rainer; Bronsema, Kees J.; van de Merbel, Nico C.

    2013-01-01

    Part I of this review discusses sample-preparation aspects of quantifying biopharmaceutical proteins in complex biological matrices by LC-MS/MS with a focus on blood-derived body fluids. We conclude Part I with a short overview over options for automating the entire analytical procedure, which is

  1. Analysis of biopharmaceutical proteins in biological matrices by LC-MS/MS I. Sample preparation

    NARCIS (Netherlands)

    Bischoff, Rainer; Bronsema, Kees J.; van de Merbel, Nico C.

    2013-01-01

    Part I of this review discusses sample-preparation aspects of quantifying biopharmaceutical proteins in complex biological matrices by LC-MS/MS with a focus on blood-derived body fluids. We conclude Part I with a short overview over options for automating the entire analytical procedure, which is in

  2. Phytochemical analysis and biological evaluation of selected African propolis samples from Cameroon and Congo

    NARCIS (Netherlands)

    Papachroni, D.; Graikou, K.; Kosalec, I.; Damianakos, H.; Ingram, V.J.; Chinou, I.

    2015-01-01

    The objective of this study was the chemical analysis of four selected samples of African propolis (Congo and Cameroon) and their biological evaluation. Twenty-one secondary metabolites belonging to four different chemical groups were isolated from the 70% ethanolic extracts of propolis and their

  3. Phytochemical analysis and biological evaluation of selected African propolis samples from Cameroon and Congo

    NARCIS (Netherlands)

    Papachroni, D.; Graikou, K.; Kosalec, I.; Damianakos, H.; Ingram, V.J.; Chinou, I.

    2015-01-01

    The objective of this study was the chemical analysis of four selected samples of African propolis (Congo and Cameroon) and their biological evaluation. Twenty-one secondary metabolites belonging to four different chemical groups were isolated from the 70% ethanolic extracts of propolis and their st

  4. In silico analyses of metagenomes from human atherosclerotic plaque samples

    DEFF Research Database (Denmark)

    Mitra, Suparna; Drautz-Moses, Daniela I; Alhede, Morten

    2015-01-01

    a challenge. RESULTS: To investigate microbiome diversity within human atherosclerotic tissue samples, we employed high-throughput metagenomic analysis on: (1) atherosclerotic plaques obtained from a group of patients who underwent endarterectomy due to recent transient cerebral ischemia or stroke. (2...

  5. A DNA methylation fingerprint of 1628 human samples

    Science.gov (United States)

    Fernandez, Agustin F.; Assenov, Yassen; Martin-Subero, Jose Ignacio; Balint, Balazs; Siebert, Reiner; Taniguchi, Hiroaki; Yamamoto, Hiroyuki; Hidalgo, Manuel; Tan, Aik-Choon; Galm, Oliver; Ferrer, Isidre; Sanchez-Cespedes, Montse; Villanueva, Alberto; Carmona, Javier; Sanchez-Mut, Jose V.; Berdasco, Maria; Moreno, Victor; Capella, Gabriel; Monk, David; Ballestar, Esteban; Ropero, Santiago; Martinez, Ramon; Sanchez-Carbayo, Marta; Prosper, Felipe; Agirre, Xabier; Fraga, Mario F.; Graña, Osvaldo; Perez-Jurado, Luis; Mora, Jaume; Puig, Susana; Prat, Jaime; Badimon, Lina; Puca, Annibale A.; Meltzer, Stephen J.; Lengauer, Thomas; Bridgewater, John; Bock, Christoph; Esteller, Manel

    2012-01-01

    Most of the studies characterizing DNA methylation patterns have been restricted to particular genomic loci in a limited number of human samples and pathological conditions. Herein, we present a compromise between an extremely comprehensive study of a human sample population with an intermediate level of resolution of CpGs at the genomic level. We obtained a DNA methylation fingerprint of 1628 human samples in which we interrogated 1505 CpG sites. The DNA methylation patterns revealed show this epigenetic mark to be critical in tissue-type definition and stemness, particularly around transcription start sites that are not within a CpG island. For disease, the generated DNA methylation fingerprints show that, during tumorigenesis, human cancer cells underwent a progressive gain of promoter CpG-island hypermethylation and a loss of CpG methylation in non-CpG-island promoters. Although transformed cells are those in which DNA methylation disruption is more obvious, we observed that other common human diseases, such as neurological and autoimmune disorders, had their own distinct DNA methylation profiles. Most importantly, we provide proof of principle that the DNA methylation fingerprints obtained might be useful for translational purposes by showing that we are able to identify the tumor type origin of cancers of unknown primary origin (CUPs). Thus, the DNA methylation patterns identified across the largest spectrum of samples, tissues, and diseases reported to date constitute a baseline for developing higher-resolution DNA methylation maps and provide important clues concerning the contribution of CpG methylation to tissue identity and its changes in the most prevalent human diseases. PMID:21613409

  6. The NYC native air sampling pilot project: using HVAC filter data for urban biological incident characterization.

    Science.gov (United States)

    Ackelsberg, Joel; Leykam, Frederic M; Hazi, Yair; Madsen, Larry C; West, Todd H; Faltesek, Anthony; Henderson, Gavin D; Henderson, Christopher L; Leighton, Terrance

    2011-09-01

    Native air sampling (NAS) is distinguished from dedicated air sampling (DAS) devices (eg, BioWatch) that are deployed to detect aerosol disseminations of biological threat agents. NAS uses filter samples from heating, ventilation, and air conditioning (HVAC) systems in commercial properties for environmental sampling after DAS detection of biological threat agent incidents. It represents an untapped, scientifically sound, efficient, widely distributed, and comparably inexpensive resource for postevent environmental sampling. Calculations predict that postevent NAS would be more efficient than environmental surface sampling by orders of magnitude. HVAC filter samples could be collected from pre-identified surrounding NAS facilities to corroborate the DAS alarm and delineate the path taken by the bioaerosol plume. The New York City (NYC) Native Air Sampling Pilot Project explored whether native air sampling would be acceptable to private sector stakeholders and could be implemented successfully in NYC. Building trade associations facilitated outreach to and discussions with property owners and managers, who expedited contact with building managers of candidate NAS properties that they managed or owned. Nominal NAS building requirements were determined; procedures to identify and evaluate candidate NAS facilities were developed; data collection tools and other resources were designed and used to expedite candidate NAS building selection and evaluation in Manhattan; and exemplar environmental sampling playbooks for emergency responders were completed. In this sample, modern buildings with single or few corporate tenants were the best NAS candidate facilities. The Pilot Project successfully demonstrated that in one urban setting a native air sampling strategy could be implemented with effective public-private collaboration.

  7. Quantitative and dynamic measurements of biological fresh samples with X-ray phase contrast tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, Masato, E-mail: hoshino@spring8.or.jp; Uesugi, Kentaro [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Tsukube, Takuro [Japanese Red Cross Kobe Hospital, 1-3-1 Wakinohamakaigandori, Chuo-ku, Kobe, Hyogo 651-0073 (Japan); Yagi, Naoto [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

    2014-10-08

    Quantitative measurements of biological fresh samples based on three-dimensional densitometry using X-ray phase contrast tomography are presented. X-ray phase contrast tomography using a Talbot grating interferometer was applied to biological fresh samples which were not fixed by any fixatives. To achieve a high-throughput measurement for the fresh samples the X-ray phase contrast tomography measurement procedure was improved. The three-dimensional structure of a fresh mouse fetus was clearly depicted as a mass density map using X-ray phase contrast tomography. The mouse fetus measured in the fresh state was then fixed by formalin and measured in the fixed state. The influence of the formalin fixation on soft tissue was quantitatively evaluated by comparing the fresh and fixed samples. X-ray phase contrast tomography was also applied to the dynamic measurement of a biological fresh sample. Morphological changes of a ring-shaped fresh pig aorta were measured tomographically under different degrees of stretching.

  8. Microfluidic solutions enabling continuous processing and monitoring of biological samples: A review.

    Science.gov (United States)

    Karle, Marc; Vashist, Sandeep Kumar; Zengerle, Roland; von Stetten, Felix

    2016-07-27

    The last decade has witnessed tremendous advances in employing microfluidic solutions enabling Continuous Processing and Monitoring of Biological Samples (CPMBS), which is an essential requirement for the control of bio-processes. The microfluidic systems are superior to the traditional inline sensors due to their ability to implement complex analytical procedures, such as multi-step sample preparation, and enabling the online measurement of parameters. This manuscript provides a backgound review of microfluidic approaches employing laminar flow, hydrodynamic separation, acoustophoresis, electrophoresis, dielectrophoresis, magnetophoresis and segmented flow for the continuous processing and monitoring of biological samples. The principles, advantages and limitations of each microfluidic approach are described along with its potential applications. The challenges in the field and the future directions are also provided.

  9. Lead Assessment in Biological Samples of Children with Different Gastrointestinal Disorders.

    Science.gov (United States)

    Shah, Faheem; Ullah, Naeem; Kazi, Tasneem Gul; Khan, Ajmal; Kandhro, Ghulam Abbas; Afridi, Hassan Imran; Arain, Mohammad Balal; Khan, Zahid; Farooq, Umar

    2016-01-01

    Lead (Pb) levels have been evaluated in the biological samples of children with different gastrointestinal disorders. Blood, scalp hair, and urine samples of children (of age 4-10 years) complaining about different gastrointestinal disorders were analyzed. For comparison, age matched healthy subjects were also included in this study. Biological samples were digested in a microwave oven prior to Pb determination by graphite furnace atomic absorption spectrometry. Significant differences in Pb profile were found between the diseased and referent children. Elevated Pb contents were observed in case of diseased children than WHO permissible limit, while normal results were obtained for healthy referents. The results were compared with those of healthy children having the same age, socioeconomic status, and residential areas.

  10. A Method for Determining the Content of Glycoproteins in Biological Samples

    Directory of Open Access Journals (Sweden)

    Yang Gao

    2016-11-01

    Full Text Available The glycoprotein purified from the mycelium extract of Tremella fuciformis was marked with iodine through the iodine substitution reaction. The content of iodine, which is indicative of the amount of the marked tremella glycoprotein (ITG, was detected with Inductively coupled plasma mass spectrometry (ICP-MS. The method was found to be stable, sensitive, and accurate at detecting the content of iodine-substituted glycoprotein, and was used in the quantitative analysis of biological samples, including blood and organs. Different biological samples were collected from rats after oral administration of ITG, and were tested for iodine content by ICP-MS to calculate the amount of ITG in the samples. The results suggested that ICP-MS is a sensitive, stable, and accurate method for detection of iodinated glycoproteins in blood and organs.

  11. Toward greener analytical techniques for the absolute quantification of peptides in pharmaceutical and biological samples.

    Science.gov (United States)

    Van Eeckhaut, Ann; Mangelings, Debby

    2015-09-10

    Peptide-based biopharmaceuticals represent one of the fastest growing classes of new drug molecules. New reaction types included in the synthesis strategies to reduce the rapid metabolism of peptides, along with the availability of new formulation and delivery technologies, resulted in an increased marketing of peptide drug products. In this regard, the development of analytical methods for quantification of peptides in pharmaceutical and biological samples is of utmost importance. From the sample preparation step to their analysis by means of chromatographic or electrophoretic methods, many difficulties should be tackled to analyze them. Recent developments in analytical techniques emphasize more and more on the use of green analytical techniques. This review will discuss the progresses in and challenges observed during green analytical method development for the quantification of peptides in pharmaceutical and biological samples.

  12. Nanocharacterization of soft biological samples in shear mode with quartz tuning fork probes.

    Science.gov (United States)

    Otero, Jorge; Gonzalez, Laura; Puig-Vidal, Manel

    2012-01-01

    Quartz tuning forks are extremely good resonators and their use is growing in scanning probe microscopy. Nevertheless, only a few studies on soft biological samples have been reported using these probes. In this work, we present the methodology to develop and use these nanosensors to properly work with biological samples. The working principles, fabrication and experimental setup are presented. The results in the nanocharacterization of different samples in different ambients are presented by using different working modes: amplitude modulation with and without the use of a Phase-Locked Loop (PLL) and frequency modulation. Pseudomonas aeruginosa bacteria are imaged in nitrogen using amplitude modulation. Microcontact printed antibodies are imaged in buffer using amplitude modulation with a PLL. Finally, metastatic cells are imaged in air using frequency modulation.

  13. Nanocharacterization of Soft Biological Samples in Shear Mode with Quartz Tuning Fork Probes

    Directory of Open Access Journals (Sweden)

    Manel Puig-Vidal

    2012-04-01

    Full Text Available Quartz tuning forks are extremely good resonators and their use is growing in scanning probe microscopy. Nevertheless, only a few studies on soft biological samples have been reported using these probes. In this work, we present the methodology to develop and use these nanosensors to properly work with biological samples. The working principles, fabrication and experimental setup are presented. The results in the nanocharacterization of different samples in different ambients are presented by using different working modes: amplitude modulation with and without the use of a Phase-Locked Loop (PLL and frequency modulation. Pseudomonas aeruginosa bacteria are imaged in nitrogen using amplitude modulation. Microcontact printed antibodies are imaged in buffer using amplitude modulation with a PLL. Finally, metastatic cells are imaged in air using frequency modulation.

  14. Direct observation of unstained wet biological samples by scanning-electron generation X-ray microscopy.

    Science.gov (United States)

    Ogura, Toshihiko

    2010-01-01

    Analytical tools of nanometre-scale resolution are indispensable in the fields of biology, physics and chemistry. One suitable tool, the soft X-ray microscope, provides high spatial resolution of visible light for wet specimens. For biological specimens, X-rays of water-window wavelength between carbon (284 eV; 4.3 nm) and oxygen (540 eV; 2.3 nm) absorption edges provide high-contrast imaging of biological samples in water. Among types of X-ray microscope, the transmission X-ray microscope using a synchrotron radiation source with diffractive zone plates offers the highest spatial resolution, approaching 15-10nm. However, even higher resolution is required to measure proteins and protein complexes in biological specimens; therefore, a new type of X-ray microscope with higher resolution that uses a simple light source is desirable. Here we report a novel scanning-electron generation X-ray microscope (SGXM) that demonstrates direct imaging of unstained wet biological specimens. We deposited wet yeasts in the space between two silicon nitride (Si(3)N(4)) films. A scanning electron beam of accelerating voltage 5 keV and current 1.6 nA irradiates the titanium (Ti)-coated Si(3)N(4) film, and the soft X-ray signal from it is detected by an X-ray photodiode (PD) placed below the sample. The SGXM can theoretically achieve better than 5 nm resolution. Our method can be utilized easily for various wet biological samples of bacteria, viruses, and protein complexes.

  15. Elimination of bioweapons agents from forensic samples during extraction of human DNA.

    Science.gov (United States)

    Timbers, Jason; Wilkinson, Della; Hause, Christine C; Smith, Myron L; Zaidi, Mohsin A; Laframboise, Denis; Wright, Kathryn E

    2014-11-01

    Collection of DNA for genetic profiling is a powerful means for the identification of individuals responsible for crimes and terrorist acts. Biologic hazards, such as bacteria, endospores, toxins, and viruses, could contaminate sites of terrorist activities and thus could be present in samples collected for profiling. The fate of these hazards during DNA isolation has not been thoroughly examined. Our goals were to determine whether the DNA extraction process used by the Royal Canadian Mounted Police eliminates or neutralizes these agents and if not, to establish methods that render samples safe without compromising the human DNA. Our results show that bacteria, viruses, and toxins were reduced to undetectable levels during DNA extraction, but endospores remained viable. Filtration of samples after DNA isolation eliminated viable spores from the samples but left DNA intact. We also demonstrated that contamination of samples with some bacteria, endospores, and toxins for longer than 1 h compromised the ability to complete genetic profiling.

  16. Solid Phase Microextraction and Related Techniques for Drugs in Biological Samples

    Directory of Open Access Journals (Sweden)

    Mohammad Mahdi Moein

    2014-01-01

    Full Text Available In drug discovery and development, the quantification of drugs in biological samples is an important task for the determination of the physiological performance of the investigated drugs. After sampling, the next step in the analytical process is sample preparation. Because of the low concentration levels of drug in plasma and the variety of the metabolites, the selected extraction technique should be virtually exhaustive. Recent developments of sample handling techniques are directed, from one side, toward automatization and online coupling of sample preparation units. The primary objective of this review is to present the recent developments in microextraction sample preparation methods for analysis of drugs in biological fluids. Microextraction techniques allow for less consumption of solvent, reagents, and packing materials, and small sample volumes can be used. In this review the use of solid phase microextraction (SPME, microextraction in packed sorbent (MEPS, and stir-bar sorbtive extraction (SBSE in drug analysis will be discussed. In addition, the use of new sorbents such as monoliths and molecularly imprinted polymers will be presented.

  17. Inductively coupled plasma mass spectrometry in the analysis of biological samples and pharmaceutical drugs

    Science.gov (United States)

    Ossipov, K.; Seregina, I. F.; Bolshov, M. A.

    2016-04-01

    Inductively coupled plasma mass spectrometry (ICP-MS) is widely used in the analysis of biological samples (whole blood, serum, blood plasma, urine, tissues, etc.) and pharmaceutical drugs. The shortcomings of this method related to spectral and non-spectral interferences are manifested in full measure in determination of the target analytes in these complex samples strongly differing in composition. The spectral interferences are caused by similarity of masses of the target component and sample matrix components. Non-spectral interferences are related to the influence of sample matrix components on the physicochemical processes taking place during formation and transportation of liquid sample aerosols into the plasma, on the value and spatial distribution of plasma temperature and on the transmission of the ion beam from the interface to mass spectrometer detector. The review is devoted to analysis of different mechanisms of appearance of non-spectral interferences and to ways for their minimization or elimination. Special attention is paid to the techniques of biological sample preparation, which largely determine the mechanisms of the influence of sample composition on the results of element determination. The ways of lowering non-spectral interferences by instrumental parameter tuning and application of internal standards are considered. The bibliography includes 189 references.

  18. Development of an improved immunoassay for detection of sorLA in cells and biological samples

    DEFF Research Database (Denmark)

    Andersen, Olav Michael; Thakurta, Ishita Guha; West, Mark J.

    , or traditional sandwich ELISA assays which are time consuming and less sensitive. Hence, the purpose of the present study is to develop a new assay called AlphaLISA which is fast and very sensitive, to measure sorLA in extremely small volumes of cells and biological samples. Methods: The Alpha...... retinopathy, and acute leukemia. Despite the overwhelming evidence regarding the role of sorLA in various diseases, there has been a lack of technologies which can precisely quantitate the levels of sorLA in various complex biological matrices. The methods are either qualitative like immunohistochemistry...

  19. Improved FIA-ABTS method for antioxidant capacity determination in different biological samples.

    Science.gov (United States)

    Bompadre, Stefano; Leone, Luciana; Politi, Alessia; Battino, Maurizio

    2004-08-01

    In order to evaluate the actual antioxidant features of foods, beverages and also plasma from patients, a number of assays have been developed in the last few years to determine the so called total antioxidant activity (TAA), intended as the cumulative capacity of a biological sample to scavenge free radicals. Most of the assays partially failed in obtaining a good reproducibility when using plasma because it is composed of a large number of substances, some of which are present at very high concentrations and possess masking features. For these reasons we have improved the widely known ABTS method by means of a FIA system where both temperature and dispersion of sample and reagent were strictly controlled. We found that temperature may be a critical aspect in the measurement of plasma TAA whilst its influence may be less important in the assay of non-complex biological samples. We demonstrated that also the reaction time may be critical, depending on the nature of the substance employed. Data confirmed the high TAA of a methylsalicylate-containing mouthrinse as well as the negligible TAA offered by the chlorhexidine containing one. White wines (Verdicchio) also displayed interesting TAA values. The improved method was useful to screen rapidly, without dilution, with very limited handling of the sample and with high repeatability the TAA of plasma in addition to chemical products, beverages and non-complex biological mixtures.

  20. Mapping Chemical and Structural Composition of Pharmaceutical and Biological Samples by Raman, Surface-Enhanced Raman and Fluorescence Spectral Imaging

    Science.gov (United States)

    Chourpa, Igor; Cohen-Jonathan, Simone; Dubois, Pierre

    Raman spectroscopy is an analytical technique recognised for its structural and conformational specificity. The efficient discrimination of molecular species by Raman is particularly potent for multidimensional microscopic imaging of complex biological environment, as demonstrated in the present book. The commonly admitted problem of Raman, low sensitivity, can often be circumvented due to high output instruments and via approaches like RRS (resonance Raman scattering), SERS (surface-enhanced Raman scattering), TERS (tip-enhanced Raman scattering) or CARS (coherent anti-Stokes Raman scattering). In contrast to the latter, RRS and SERS are realizable with less sophisticated set-up based on common Raman systems. Although more invasive than RRS, SERS provides better sensitivity and quenching of fluorescence. SERRS (surface-enhanced resonance Raman scattering) spectroscopy can be used in coupling with fluorescence and competes in selectivity and sensitivity with spectrofluorimetry. In the chapter below, we use recent applications made in our group to illustrate the use of Raman and SERRS spectral imaging for characterization of biological samples (animal subcutaneous tissue, human cancer cells) and pharmaceutical samples (microparticles for drug delivery, fibres for wound dressing). After a brief description of experimental details on spectral imaging, the chapter will focus on results concerning (i) biocompatible pharmaceutical materials made of alginates and (ii) anticancer drugs in pharmaceutical forms and in biological systems.

  1. Aggression in humans: what is its biological foundation?

    Science.gov (United States)

    Albert, D J; Walsh, M L; Jonik, R H

    1993-01-01

    Although human aggression is frequently inferred to parallel aggression based on testosterone in nonprimate mammals, there is little concrete support for this position. High- and low-aggression individuals do not consistently differ in serum testosterone. Aggression does not change at puberty when testosterone levels increase. Aggression does not increase in hypogonadal males (or females) when exogenous testosterone is administered to support sexual activity. Similarly, there are no reports that aggression increases in hirsute females even though testosterone levels may rise to 200% above normal. Conversely, castration or antiandrogen administration to human males is not associated with a consistent decrease in aggression. Finally, changes in human aggression associated with neuropathology are not consistent with current knowledge of the neural basis of testosterone-dependent aggression. In contrast, human aggression does have a substantial number of features in common with defensive aggression seen in nonprimate mammals. It is present at all age levels, is displayed by both males and females, is directed at both males and females, and is not dependent on seasonal changes in hormone levels or experiential events such as sexual activity. As would be expected from current knowledge of the neural system controlling defensive aggression, aggression in humans increases with tumors in the medial hypothalamus and septal region, and with seizure activity in the amygdala. It decreases with lesions in the amygdala. The inference that human aggression has its roots in the defensive aggression of nonprimate mammals is in general agreement with evidence on the consistency of human aggressiveness over age, with similarities in male and female aggressiveness in laboratory studies, and with observations that some neurological disturbances contribute to criminal violence. This evidence suggests that human aggression has its biological roots in the defensive aggression of nonprimate

  2. Human Biological Monitoring of Diisononyl Phthalate and Diisodecyl Phthalate: A Review

    Directory of Open Access Journals (Sweden)

    Gurusankar Saravanabhavan

    2012-01-01

    Full Text Available High molecular-weight phthalates, such as diisononyl phthalate (DINP, and diisodecyl phthalate (DIDP, are widely used as plasticizers in the manufacturing of polymers and consumer products. Human biological monitoring studies have employed the metabolites of DINP and DIDP as biomarkers to assess human exposure. In this review, we summarize and analyze publicly available scientific data on chemistry, metabolism, and excretion kinetics, of DINP and DIDP, to identify specific and sensitive metabolites. Human biological monitoring data on DINP and DIDP are scrutinised to assess the suitability of these metabolites as biomarkers of exposure. Results from studies carried out in animals and humans indicate that phthalates are metabolised rapidly and do not bioaccmulate. During Phase-I metabolism, ester hydrolysis of DINP and DIDP leads to the formation of hydrolytic monoesters. These primary metabolites undergo further oxidation reactions to produce secondary metabolites. Hence, the levels of secondary metabolites of DINP and DIDP in urine are found to be always higher than the primary metabolites. Results from human biological monitoring studies have shown that the secondary metabolites of DINP and DIDP in urine were detected in almost all tested samples, while the primary metabolites were detected in only about 10% of the samples. This indicates that the secondary metabolites are very sensitive biomarkers of DINP/DIDP exposure while primary metabolites are not. The NHANES data indicate that the median concentrations of MCIOP and MCINP (secondary metabolites of DINP and DIDP, resp. at a population level are about 5.1 μg/L and 2.7 μg/L, respectively. Moreover, the available biological monitoring data suggest that infants/children are exposed to higher levels of phthalates than adults.

  3. Physicochemical characteristics and biological activities of seasonal atmospheric particulate matter sampling in two locations of Paris.

    Science.gov (United States)

    Baulig, Augustin; Poirault, Jean-Jacques; Ausset, Patrick; Schins, Roel; Shi, Tingming; Baralle, Delphine; Dorlhene, Pascal; Meyer, Martine; Lefevre, Roger; Baeza-Squiban, Armelle; Marano, Francelyne

    2004-11-15

    Fine particulate matter present in urban areas seems to be incriminated in respiratory disorders. The aim of this study was to relate physicochemical characteristics of PM2.5 (particulate matter collected with a 50% efficiency for particles with an aerodynamic diameter of 2.5 microm) to their biological activities toward a bronchial epithelial cell line 16-HBE. Two seasonal sampling campaigns of particles were realized, respectively, in a kerbside and an urban background station in Paris. Sampled-PM2.5 mainly consist of particles with a size below 1 microm and are mainly composed of soot as assessed by analytical scanning electron microscopy. The different PM2.5 samples contrasted in their PAH content, which was the highest in the kerbside station in winter, as well as in their metal content. Kerbside station samples were characterized by the highest Fe and Cu content, which appears correlated to their hydroxyl radical generating properties measured by electron paramagnetic resonance. Particles were compared by their capacity to induce cytotoxicity, intracellular ROS production, and proinflammatory cytokine release (GM-CSF and TNF-alpha). At a concentration of 10 microg/cm2, all samples induced peroxide production and cytokine release to the similar extent in the absence of cytotoxicity. In conclusion, whereas the PM2.5 samples differ by their PAH and metal composition, they induce the same biological responses likely either due to components bioavailability and/ or interactions between PM components.

  4. Improved preparation of small biological samples for mercury analysis using cold vapor atomic absorption spectroscopy.

    Science.gov (United States)

    Adair, B M; Cobb, G P

    1999-05-01

    Concentrations of mercury in biological samples collected for environmental studies are often less than 0.1 microgram/g. Low mercury concentrations and small organ sizes in many wildlife species (approximately 0.1 g) increase the difficulty of mercury determination at environmentally relevant concentrations. We have developed a digestion technique to extract mercury from small (0.1 g), biological samples at these relevant concentrations. Mean recoveries (+/- standard error) from validation trials of mercury fortified tissue samples using cold vapor atomic absorption spectroscopy for analysis ranged from 102 +/- 4.3% (2.5 micrograms/L, n = 15) to 108 +/- 1.4% (25 micrograms/L, n = 15). Recoveries of inorganic mercury were 99 +/- 5 (n = 19) for quality assurance samples analyzed during environmental evaluations conducted during a 24 month period. This technique can be used to determine total mercury concentrations of 60 ng Hg/g sample. Samples can be analyzed in standard laboratories in a short time, at minimal cost. The technique is versatile and can be used to determine mercury concentrations in several different matrices, limiting the time and expense of method development and validation.

  5. A Prototype Ice-Melting Probe for Collecting Biological Samples from Cryogenic Ice at Low Pressure

    Science.gov (United States)

    Davis, Ashley

    2017-08-01

    In the Solar System, the surface of an icy moon is composed of irregular ice formations at cryogenic temperatures (ice, must contain a device that collects samples without refreezing liquid and without sublimation of ice. In addition, if the samples are biological in nature, then precautions must be taken to ensure the samples do not overheat or mix with the oxidized layer. To achieve these conditions, the collector must maintain temperatures close to maintenance or growth conditions of the organism (ice and directs the meltwater upward into a reservoir. The force on the probe is proportional to the height of meltwater (pressure) obtained in the system and allows regulation of the melt rate and temperature of the sample. The device can collect 5-50 mL of meltwater from the surface of an ice block at 233-208 K with an environmental pressure of less than 10-2 atm while maintaining a sample temperature between 273 and 293 K. These conditions maintain most biological samples in a pristine state and maintain the integrity of most organisms' structure and function.

  6. Characterization of femtosecond laser-induced breakdown spectroscopy (fsLIBS) and applications for biological samples.

    Science.gov (United States)

    Gill, Ruby K; Knorr, Florian; Smith, Zachary J; Kahraman, Mehmet; Madsen, Dorte; Larsen, Delmar S; Wachsmann-Hogiu, Sebastian

    2014-01-01

    We characterize the femtosecond laser-induced breakdown spectroscopy (fsLIBS) signal for biological tissues as a function of different excitation parameters with femtosecond laser systems. These parameters include laser energy, depth of focus, and number of pulses per focal volume. We used femtosecond laser pulses of 800 nm and energy between 25 and 123 μJ to generate LIBS signals in biological tissues. As expected, we observed a linear increase in the fsLIBS intensity as a function of the laser energy. In addition, we show that moving the beam out of focus and the presence of overlapping pulses on the same focal area leads to a decrease in fsLIBS intensity due to changes in focal spot size. We also demonstrate that fsLIBS can distinguish between different biological tissue samples.

  7. Elemental and isotopic imaging of biological samples using NanoSIMS.

    Science.gov (United States)

    Kilburn, Matt R; Clode, Peta L

    2014-01-01

    With its low detection limits and the ability to analyze most of the elements in the periodic table, secondary ion mass spectrometry (SIMS) represents one of the most versatile in situ analytical techniques available, and recent developments have resulted in significant advantages for the use of imaging mass spectrometry in biological and biomedical research. Increases in spatial resolution and sensitivity allow detailed interrogation of samples at relevant scales and chemical concentrations. Advances in dynamic SIMS, specifically with the advent of NanoSIMS, now allow the tracking of stable isotopes within biological systems at subcellular length scales, while static SIMS combines subcellular imaging with molecular identification. In this chapter, we present an introduction to the SIMS technique, with particular reference to NanoSIMS, and discuss its application in biological and biomedical research.

  8. Biological characteristics of cell lines of human dental alveolus

    Institute of Scientific and Technical Information of China (English)

    陈世璋; 黄靖香; 孙明学; 赵斌

    2003-01-01

    Objective To investigate the biological characteristics of cell lines of healthy and diseased human dental alveoli. Methods Primary cell lines from either healthy or diseased human dental alveoli were obtained. Two cell lines, H-258 and H-171 derived from healthy and diseased human tissues respectively, were selected for morphological study and research on their growth and aging, using cell counting, and histochemical and immunohistochemical staining. Results Primary cell lines were successfully established from innormal dental alveoli. After freezing and thawing for three times, cell growth was continued and no morphological alterations were observed. The doubling time was 53.4 hours and mean division index (MDI) was 4‰. Cells were kept normal after twenty generations with no obvious reduction of doubling time and MDI. Of twenty-six primary cell lines derived from healthy human dental alveoli, only three cell lines achieved generation. After freezing and thawing for twice, cultured cells were still alive at a decreased growth speed, with doubling time of 85.9 hours and MDI of 3‰. Both cell lines, H-171 and H-258, shared the characteristics of osteoblast. Conclusions Primary cell lines of diseased human dental alveoli show greater growth potential. All cell lines of dental alveoli share characteristics of osteoblast. The technique we developed may be put into practice for the treatment of abnormal dental alveoli.

  9. BIOLOGY OF HUMAN MALARIA PLASMODIA INCLUDING PLASMODIUM KNOWLESI

    Directory of Open Access Journals (Sweden)

    Spinello Antinori

    2012-03-01

    Full Text Available Malaria is a vector-borne infection caused by unicellular parasite of the genus Plasmodium. Plasmodia are obligate intracellular parasites that in humans after a clinically silent replication phase in the liver are able to infect and replicate within the erythrocytes. Four species (P.falciparum, P.malariae, P.ovale and P.vivax are traditionally recognized as responsible of natural infection in human beings but the recent upsurge of P.knowlesi malaria in South-East Asia has led clinicians to consider it as the fifth human malaria parasite. Recent studies in wild-living apes in Africa have revealed that P.falciparum, the most deadly form of human malaria, is not only human-host restricted as previously believed and its phylogenetic lineage is much more complex with new species identified in gorilla, bonobo and chimpanzee. Although less impressive, new data on biology of P.malariae, P.ovale and P.vivax are also emerging and will be briefly discussed in this review.

  10. Evolutionary Developmental Biology and Human Language Evolution: Constraints on Adaptation.

    Science.gov (United States)

    Fitch, W Tecumseh

    2012-12-01

    A tension has long existed between those biologists who emphasize the importance of adaptation by natural selection and those who highlight the role of phylogenetic and developmental constraints on organismal form and function. This contrast has been particularly noticeable in recent debates concerning the evolution of human language. Darwin himself acknowledged the existence and importance of both of these, and a long line of biologists have followed him in seeing, in the concept of "descent with modification", a framework naturally able to incorporate both adaptation and constraint. Today, the integrated perspective of modern evolutionary developmental biology ("evo-devo") allows a more subtle and pluralistic approach to these traditional questions, and has provided several examples where the traditional notion of "constraint" can be cashed out in specific, mechanistic terms. This integrated viewpoint is particularly relevant to the evolution of the multiple mechanisms underlying human language, because of the short time available for novel aspects of these mechanisms to evolve and be optimized. Comparative data indicate that many cognitive aspects of human language predate humans, suggesting that pre-adaptation and exaptation have played important roles in language evolution. Thus, substantial components of what many linguists call "Universal Grammar" predate language itself. However, at least some of these older mechanisms have been combined in ways that generate true novelty. I suggest that we can insightfully exploit major steps forward in our understanding of evolution and development, to gain a richer understanding of the principles that underlie human language evolution.

  11. Axial-scanning low-coherence interferometer method for noncontact thickness measurement of biological samples.

    Science.gov (United States)

    Kim, Do-Hyun; Song, Chul-Gyu; Ilev, Ilko K; Kang, Jin U

    2011-02-20

    We investigated a high-precision optical method for measuring the thickness of biological samples regardless of their transparency. The method is based on the precise measurement of optical path length difference of the end surfaces of objects, using a dual-arm axial-scanning low-coherence interferometer. This removes any consideration of the shape, thickness, or transparency of testing objects when performing the measurement. Scanning the reference simplifies the measurement setup, resulting in unambiguous measurement. Using a 1310 nm wavelength superluminescent diode, with a 65 nm bandwidth, the measurement accuracy was as high as 11.6 μm. We tested the method by measuring the thickness of both transparent samples and nontransparent soft biological tissues.

  12. Axial-scanning low-coherence interferometer method for noncontact thickness measurement of biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Do-Hyun; Song, Chul-Gyu; Ilev, Ilko K.; Kang, Jin U.

    2011-02-20

    We investigated a high-precision optical method for measuring the thickness of biological samples regardless of their transparency. The method is based on the precise measurement of optical path length difference of the end surfaces of objects, using a dual-arm axial-scanning low-coherence interferometer. This removes any consideration of the shape, thickness, or transparency of testing objects when performing the measurement. Scanning the reference simplifies the measurement setup, resulting in unambiguous measurement. Using a 1310 nm wavelength superluminescent diode, with a 65 nm bandwidth, the measurement accuracy was as high as 11.6 {mu}m. We tested the method by measuring the thickness of both transparent samples and nontransparent soft biological tissues.

  13. Electroanalytical Determination of Danofloxacin in Biological Samples Using Square Wave Voltammetry

    Directory of Open Access Journals (Sweden)

    Chirley Vanessa Boone

    2014-10-01

    Full Text Available The voltammetric behavior of danofloxacin (DFX has been studied, in aqueous solution, on a glassy carbon electrode using square wave voltammetry (SWV as electroanalytical technique. After optimization of the experimental conditions, DFX was analyzed in spiked biologic samples using a Britton-Robinson buffer with pH = 5.0 as the supporting electrolyte. Oxidation occurs at 0.98 V vs. Ag/AgCl in a two-electron process controlled by adsorption of the electrogenerated products on the electrode surface. A acceptable recovery was obtained for assay of spiked biologic samples, with value of 98.7% for the swine urine and 95.3 % for the bovine urine.

  14. Biology and relevance of human acute myeloid leukemia stem cells.

    Science.gov (United States)

    Thomas, Daniel; Majeti, Ravindra

    2017-03-23

    Evidence of human acute myeloid leukemia stem cells (AML LSCs) was first reported nearly 2 decades ago through the identification of rare subpopulations of engrafting cells in xenotransplantation assays. These AML LSCs were shown to reside at the apex of a cellular hierarchy that initiates and maintains the disease, exhibiting properties of self-renewal, cell cycle quiescence, and chemoresistance. This cancer stem cell model offers an explanation for chemotherapy resistance and disease relapse and implies that approaches to treatment must eradicate LSCs for cure. More recently, a number of studies have both refined and expanded our understanding of LSCs and intrapatient heterogeneity in AML using improved xenotransplant models, genome-scale analyses, and experimental manipulation of primary patient cells. Here, we review these studies with a focus on the immunophenotype, biological properties, epigenetics, genetics, and clinical associations of human AML LSCs and discuss critical questions that need to be addressed in future research. © 2017 by The American Society of Hematology.

  15. Efficient expression and purification of biologically active human cystatin proteins.

    Science.gov (United States)

    Chauhan, Sakshi; Tomar, Raghuvir S

    2016-02-01

    Cystatins are reversible cysteine protease inhibitor proteins. They are known to play important roles in controlling cathepsins, neurodegenerative disease, and in immune system regulation. Production of recombinant cystatin proteins is important for biochemical and function characterization. In this study, we cloned and expressed human stefin A, stefin B and cystatin C in Escherichia coli. Human stefin A, stefin B and cystatin C were purified from soluble fraction. For cystatin C, we used various chaperone plasmids to make cystatin C soluble, as it is reported to localize in inclusion bodies. Trigger factor, GroES-GroEL, DnaK-DnaJ-GrpE chaperones lead to the presence of cystatin C in the soluble fraction. Immobilized metal affinity chromatography, glutathione sepharose and anion exchange chromatography techniques were employed for efficient purification of these proteins. Their biological activities were tested by inhibition assays against cathepsin L and H3 protease.

  16. Sampling designs matching species biology produce accurate and affordable abundance indices

    Directory of Open Access Journals (Sweden)

    Grant Harris

    2013-12-01

    Full Text Available Wildlife biologists often use grid-based designs to sample animals and generate abundance estimates. Although sampling in grids is theoretically sound, in application, the method can be logistically difficult and expensive when sampling elusive species inhabiting extensive areas. These factors make it challenging to sample animals and meet the statistical assumption of all individuals having an equal probability of capture. Violating this assumption biases results. Does an alternative exist? Perhaps by sampling only where resources attract animals (i.e., targeted sampling, it would provide accurate abundance estimates more efficiently and affordably. However, biases from this approach would also arise if individuals have an unequal probability of capture, especially if some failed to visit the sampling area. Since most biological programs are resource limited, and acquiring abundance data drives many conservation and management applications, it becomes imperative to identify economical and informative sampling designs. Therefore, we evaluated abundance estimates generated from grid and targeted sampling designs using simulations based on geographic positioning system (GPS data from 42 Alaskan brown bears (Ursus arctos. Migratory salmon drew brown bears from the wider landscape, concentrating them at anadromous streams. This provided a scenario for testing the targeted approach. Grid and targeted sampling varied by trap amount, location (traps placed randomly, systematically or by expert opinion, and traps stationary or moved between capture sessions. We began by identifying when to sample, and if bears had equal probability of capture. We compared abundance estimates against seven criteria: bias, precision, accuracy, effort, plus encounter rates, and probabilities of capture and recapture. One grid (49 km2 cells and one targeted configuration provided the most accurate results. Both placed traps by expert opinion and moved traps between capture

  17. Sampling designs matching species biology produce accurate and affordable abundance indices

    Science.gov (United States)

    Farley, Sean; Russell, Gareth J.; Butler, Matthew J.; Selinger, Jeff

    2013-01-01

    Wildlife biologists often use grid-based designs to sample animals and generate abundance estimates. Although sampling in grids is theoretically sound, in application, the method can be logistically difficult and expensive when sampling elusive species inhabiting extensive areas. These factors make it challenging to sample animals and meet the statistical assumption of all individuals having an equal probability of capture. Violating this assumption biases results. Does an alternative exist? Perhaps by sampling only where resources attract animals (i.e., targeted sampling), it would provide accurate abundance estimates more efficiently and affordably. However, biases from this approach would also arise if individuals have an unequal probability of capture, especially if some failed to visit the sampling area. Since most biological programs are resource limited, and acquiring abundance data drives many conservation and management applications, it becomes imperative to identify economical and informative sampling designs. Therefore, we evaluated abundance estimates generated from grid and targeted sampling designs using simulations based on geographic positioning system (GPS) data from 42 Alaskan brown bears (Ursus arctos). Migratory salmon drew brown bears from the wider landscape, concentrating them at anadromous streams. This provided a scenario for testing the targeted approach. Grid and targeted sampling varied by trap amount, location (traps placed randomly, systematically or by expert opinion), and traps stationary or moved between capture sessions. We began by identifying when to sample, and if bears had equal probability of capture. We compared abundance estimates against seven criteria: bias, precision, accuracy, effort, plus encounter rates, and probabilities of capture and recapture. One grid (49 km2 cells) and one targeted configuration provided the most accurate results. Both placed traps by expert opinion and moved traps between capture sessions, which

  18. [Fusarium graminearum presence in wheat samples for human consumption].

    Science.gov (United States)

    Martinez, Mauro; Castañares, Eliana; Dinolfo, María I; Pacheco, Walter G; Moreno, María V; Stenglein, Sebastián A

    2014-01-01

    One of the most important diseases in cereal crops is Fusarium head blight, being Fusarium graminearum the main etiological agent. This fungus has the ability to produce a wide spectrum and quantity of toxins, especially deoxynivalenol (DON). During the last crop season (2012-2013) the climatic conditions favored Fusarium colonization. The objective of this work was to determine the presence of this fungus as well as the DON content in 50 wheat grain samples. Our results showed that 80% of the samples were contaminated with Fusarium graminearum. Twenty four percent (24%) of the samples contained ≥ 1μg/g DON, 26% ranged from 0,5 and 0,99μg/g, and the remaining 50% had values lower than 0,5μg/g. Correlation was found between the presence of Fusarium graminearum and DON. It is necessary to establish DON limit values in wheat grains for human consumption.

  19. Applying the community partnership approach to human biology research.

    Science.gov (United States)

    Ravenscroft, Julia; Schell, Lawrence M; Cole, Tewentahawih'tha'

    2015-01-01

    Contemporary human biology research employs a unique skillset for biocultural analysis. This skillset is highly appropriate for the study of health disparities because disparities result from the interaction of social and biological factors over one or more generations. Health disparities research almost always involves disadvantaged communities owing to the relationship between social position and health in stratified societies. Successful research with disadvantaged communities involves a specific approach, the community partnership model, which creates a relationship beneficial for researcher and community. Paramount is the need for trust between partners. With trust established, partners share research goals, agree on research methods and produce results of interest and importance to all partners. Results are shared with the community as they are developed; community partners also provide input on analyses and interpretation of findings. This article describes a partnership-based, 20 year relationship between community members of the Akwesasne Mohawk Nation and researchers at the University at Albany. As with many communities facing health disparity issues, research with Native Americans and indigenous peoples generally is inherently politicized. For Akwesasne, the contamination of their lands and waters is an environmental justice issue in which the community has faced unequal exposure to, and harm by environmental toxicants. As human biologists engage in more partnership-type research, it is important to understand the long term goals of the community and what is at stake so the research circle can be closed and 'helicopter' style research avoided.

  20. Reactive oxygen species and vascular biology: implications in human hypertension.

    Science.gov (United States)

    Touyz, Rhian M; Briones, Ana M

    2011-01-01

    Increased vascular production of reactive oxygen species (ROS; termed oxidative stress) has been implicated in various chronic diseases, including hypertension. Oxidative stress is both a cause and a consequence of hypertension. Although oxidative injury may not be the sole etiology, it amplifies blood pressure elevation in the presence of other pro-hypertensive factors. Oxidative stress is a multisystem phenomenon in hypertension and involves the heart, kidneys, nervous system, vessels and possibly the immune system. Compelling experimental and clinical evidence indicates the importance of the vasculature in the pathophysiology of hypertension and as such much emphasis has been placed on the (patho)biology of ROS in the vascular system. A major source for cardiovascular, renal and neural ROS is a family of non-phagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox), including the prototypic Nox2 homolog-based NADPH oxidase, as well as other Noxes, such as Nox1 and Nox4. Nox-derived ROS is important in regulating endothelial function and vascular tone. Oxidative stress is implicated in endothelial dysfunction, inflammation, hypertrophy, apoptosis, migration, fibrosis, angiogenesis and rarefaction, important processes involved in vascular remodeling in hypertension. Despite a plethora of data implicating oxidative stress as a causative factor in experimental hypertension, findings in human hypertension are less conclusive. This review highlights the importance of ROS in vascular biology and focuses on the potential role of oxidative stress in human hypertension.

  1. Preconcentration and determination of heavy metals in water, sediment and biological samples

    Directory of Open Access Journals (Sweden)

    Shirkhanloo Hamid

    2011-01-01

    Full Text Available In this study, a simple, sensitive and accurate column preconcentration method was developed for the determination of Cd, Cu and Pb ions in river water, urine and sediment samples by flame atomic absorption spectrometry. The procedure is based on the retention of the analytes on a mixed cellulose ester membrane (MCEM column from buffered sample solutions and then their elution from the column with nitric acid. Several parameters, such as pH of the sample solution, volume of the sample and eluent and flow rates of the sample were evaluated. The effects of diverse ions on the preconcentration were also investigated. The recoveries were >95 %. The developed method was applied to the determination of trace metal ions in river water, urine and sediment samples, with satisfactory results. The 3δ detection limits for Cu, Pb and Cd were found to be 2, 3 and 0.2 μg dm−3, respectively. The presented procedure was successfully applied for determination of the copper, lead and cadmium contents in real samples, i.e., river water and biological samples.

  2. Isolation of biologically-active exosomes from human plasma.

    Science.gov (United States)

    Muller, Laurent; Hong, Chang-Sook; Stolz, Donna B; Watkins, Simon C; Whiteside, Theresa L

    2014-09-01

    Effects of exosomes present in human plasma on immune cells have not been examined in detail. Immunological studies with plasma-derived exosomes require their isolation by procedures involving ultracentrifugation. These procedures were largely developed using supernatants of cultured cells. To test biologic activities of plasma-derived exosomes, methods are necessary that ensure adequate recovery of exosome fractions free of contaminating larger vesicles, cell fragments and protein/nucleic acid aggregates. Here, an optimized method for exosome isolation from human plasma/serum specimens of normal controls (NC) or cancer patients and its advantages and pitfalls are described. To remove undesirable plasma-contaminating components, ultrafiltration of differentially-centrifuged plasma/serum followed by size-exclusion chromatography prior to ultracentrifugation facilitated the removal of contaminants. Plasma or serum was equally acceptable as a source of exosomes based on the recovered protein levels (in μg protein/mL plasma) and TEM image quality. Centrifugation on sucrose density gradients led to large exosome losses. Fresh plasma was the best source of morphologically-intact exosomes, while the use of frozen/thawed plasma decreased exosome purity but not their biologic activity. Treatments of frozen plasma with DNAse, RNAse or hyaluronidase did not improve exosome purity and are not recommended. Cancer patients' plasma consistently yielded more isolated exosomes than did NCs' plasma. Cancer patients' exosomes also mediated higher immune suppression as evidenced by decreased CD69 expression on responder CD4+ T effector cells. Thus, the described procedure yields biologically-active, morphologically-intact exosomes that have reasonably good purity without large protein losses and can be used for immunological, biomarker and other studies.

  3. The Tip-Sample Interaction in Atomic Force Microscopy and its Implications for Biological Applications.

    Science.gov (United States)

    Baselt, David Randall

    This thesis describes the construction of an atomic force microscope and its application to the study of tip -sample interactions, primarily through the use of friction and hardness (elasticity) imaging. Part one describes the atomic force microscope, which consists of a scanned-cantilever stage (chapter 2); a versatile digital signal processor-based control system with self-optimizing feedback, lock-in amplifier emulation (for hardness imaging), and macro programmability (chapter 3); and image processing software (chapter 4). Part two describes a number of results that have helped to characterize the tip-sample interaction and the contact imaging modes used for its study. Meniscus forces act laterally as well as normally, and that they vary with position (chapter 5). Friction measurements couple with scanner position and feedback, and the meniscus effects friction images (chapter 6). Sliding of the tip over the sample surface introduces slope-dependence into hardness measurements (chapter 7). Dull tips can create prominent topography artifacts even on very flat surfaces (chapter 8). In an investigation of collagen fibrils, AFM has revealed the characteristic 65 nm banding pattern, a second, minor banding pattern, and microfibrils that run along the fibril axis. The distribution of proteoglycans along the fibrils creates a characteristic pattern in friction images. Although imaging in water reduces interaction forces, water can also make biological samples more sensitive to force. However, for robust biological samples imaged in air, tip shape presents a greater obstacle than tip -sample interaction forces to obtaining high-resolution images. Tip contamination increases tip-sample friction and can occasionally improve resolution (chapter 9). For a separate project I have designed a general -purpose nearfield scanning optical microscope (chapter 10).

  4. Identification of biologically relevant enhancers in human erythroid cells.

    Science.gov (United States)

    Su, Mack Y; Steiner, Laurie A; Bogardus, Hannah; Mishra, Tejaswini; Schulz, Vincent P; Hardison, Ross C; Gallagher, Patrick G

    2013-03-22

    Identification of cell type-specific enhancers is important for understanding the regulation of programs controlling cellular development and differentiation. Enhancers are typically marked by the co-transcriptional activator protein p300 or by groups of cell-expressed transcription factors. We hypothesized that a unique set of enhancers regulates gene expression in human erythroid cells, a highly specialized cell type evolved to provide adequate amounts of oxygen throughout the body. Using chromatin immunoprecipitation followed by massively parallel sequencing, genome-wide maps of candidate enhancers were constructed for p300 and four transcription factors, GATA1, NF-E2, KLF1, and SCL, using primary human erythroid cells. These data were combined with gene expression analyses, and candidate enhancers were identified. Consistent with their predicted function as candidate enhancers, there was statistically significant enrichment of p300 and combinations of co-localizing erythroid transcription factors within 1-50 kb of the transcriptional start site (TSS) of genes highly expressed in erythroid cells. Candidate enhancers were also enriched near genes with known erythroid cell function or phenotype. Candidate enhancers exhibited moderate conservation with mouse and minimal conservation with nonplacental vertebrates. Candidate enhancers were mapped to a set of erythroid-associated, biologically relevant, SNPs from the genome-wide association studies (GWAS) catalogue of NHGRI, National Institutes of Health. Fourteen candidate enhancers, representing 10 genetic loci, mapped to sites associated with biologically relevant erythroid traits. Fragments from these loci directed statistically significant expression in reporter gene assays. Identification of enhancers in human erythroid cells will allow a better understanding of erythroid cell development, differentiation, structure, and function and provide insights into inherited and acquired hematologic disease.

  5. Potentiometric detection in UPLC as an easy alternative to determine cocaine in biological samples.

    Science.gov (United States)

    Daems, Devin; van Nuijs, Alexander L N; Covaci, Adrian; Hamidi-Asl, Ezat; Van Camp, Guy; Nagels, Luc J

    2015-07-01

    The analytical methods which are often used for the determination of cocaine in complex biological matrices are a prescreening immunoassay and confirmation by chromatography combined with mass spectrometry. We suggest an ultra-high-pressure liquid chromatography combined with a potentiometric detector, as a fast and practical method to detect and quantify cocaine in biological samples. An adsorption/desorption model was used to investigate the usefulness of the potentiometric detector to determine cocaine in complex matrices. Detection limits of 6.3 ng mL(-1) were obtained in plasma and urine, which is below the maximum residue limit (MRL) of 25 ng mL(-1). A set of seven plasma samples and 10 urine samples were classified identically by both methods as exceeding the MRL or being inferior to it. The results obtained with the UPLC/potentiometric detection method were compared with the results obtained with the UPLC/MS method for samples spiked with varying cocaine concentrations. The intraclass correlation coefficient was 0.997 for serum (n =7) and 0.977 for urine (n =8). As liquid chromatography is an established technique, and as potentiometry is very simple and cost-effective in terms of equipment, we believe that this method is potentially easy, inexpensive, fast and reliable.

  6. Estimating Sampling Selection Bias in Human Genetics: A Phenomenological Approach

    Science.gov (United States)

    Risso, Davide; Taglioli, Luca; De Iasio, Sergio; Gueresi, Paola; Alfani, Guido; Nelli, Sergio; Rossi, Paolo; Paoli, Giorgio; Tofanelli, Sergio

    2015-01-01

    This research is the first empirical attempt to calculate the various components of the hidden bias associated with the sampling strategies routinely-used in human genetics, with special reference to surname-based strategies. We reconstructed surname distributions of 26 Italian communities with different demographic features across the last six centuries (years 1447–2001). The degree of overlapping between "reference founding core" distributions and the distributions obtained from sampling the present day communities by probabilistic and selective methods was quantified under different conditions and models. When taking into account only one individual per surname (low kinship model), the average discrepancy was 59.5%, with a peak of 84% by random sampling. When multiple individuals per surname were considered (high kinship model), the discrepancy decreased by 8–30% at the cost of a larger variance. Criteria aimed at maximizing locally-spread patrilineages and long-term residency appeared to be affected by recent gene flows much more than expected. Selection of the more frequent family names following low kinship criteria proved to be a suitable approach only for historically stable communities. In any other case true random sampling, despite its high variance, did not return more biased estimates than other selective methods. Our results indicate that the sampling of individuals bearing historically documented surnames (founders' method) should be applied, especially when studying the male-specific genome, to prevent an over-stratification of ancient and recent genetic components that heavily biases inferences and statistics. PMID:26452043

  7. Challenges of biological sample preparation for SIMS imaging of elements and molecules at subcellular resolution

    Energy Technology Data Exchange (ETDEWEB)

    Chandra, Subhash [Cornell SIMS Laboratory, Department of Earth and Atmospheric Sciences, Snee Hall, Cornell University, Ithaca, NY 14853 (United States)], E-mail: sc40@cornell.edu

    2008-12-15

    Secondary ion mass spectrometry (SIMS) based imaging techniques capable of subcellular resolution characterization of elements and molecules are becoming valuable tools in many areas of biology and medicine. Due to high vacuum requirements of SIMS, the live cells cannot be analyzed directly in the instrument. The sample preparation, therefore, plays a critical role in preserving the native chemical composition for SIMS analysis. This work focuses on the evaluation of frozen-hydrated and frozen freeze-dried sample preparations for SIMS studies of cultured cells with a CAMECA IMS-3f dynamic SIMS ion microscope instrument capable of producing SIMS images with a spatial resolution of 500 nm. The sandwich freeze-fracture method was used for fracturing the cells. The complimentary fracture planes in the plasma membrane were characterized by field-emission secondary electron microscopy (FESEM) in the frozen-hydrated state. The cells fractured at the dorsal surface were used for SIMS analysis. The frozen-hydrated SIMS analysis of individual cells under dynamic primary ion beam (O{sub 2}{sup +}) revealed local secondary ion signal enhancements correlated with the water image signals of {sup 19}(H{sub 3}O){sup +}. A preferential removal of water from the frozen cell matrix in the Z-axis was also observed. These complications render the frozen-hydrated sample type less desirable for subcellular dynamic SIMS studies. The freeze-drying of frozen-hydrated cells, either inside the instrument or externally in a freeze-drier, allowed SIMS imaging of subcellular chemical composition. Morphological evaluations of fractured freeze-dried cells with SEM and confocal laser scanning microscopy (CLSM) revealed well-preserved mitochondria, Golgi apparatus, and stress fibers. SIMS analysis of fractured freeze-dried cells revealed well-preserved chemical composition of even the most highly diffusible ions like K{sup +} and Na{sup +} in physiologically relevant concentrations. The high K

  8. Non-target time trend screening: a data reduction strategy for detecting emerging contaminants in biological samples.

    Science.gov (United States)

    Plassmann, Merle M; Tengstrand, Erik; Åberg, K Magnus; Benskin, Jonathan P

    2016-06-01

    Non-targeted mass spectrometry-based approaches for detecting novel xenobiotics in biological samples are hampered by the occurrence of naturally fluctuating endogenous substances, which are difficult to distinguish from environmental contaminants. Here, we investigate a data reduction strategy for datasets derived from a biological time series. The objective is to flag reoccurring peaks in the time series based on increasing peak intensities, thereby reducing peak lists to only those which may be associated with emerging bioaccumulative contaminants. As a result, compounds with increasing concentrations are flagged while compounds displaying random, decreasing, or steady-state time trends are removed. As an initial proof of concept, we created artificial time trends by fortifying human whole blood samples with isotopically labelled standards. Different scenarios were investigated: eight model compounds had a continuously increasing trend in the last two to nine time points, and four model compounds had a trend that reached steady state after an initial increase. Each time series was investigated at three fortification levels and one unfortified series. Following extraction, analysis by ultra performance liquid chromatography high-resolution mass spectrometry, and data processing, a total of 21,700 aligned peaks were obtained. Peaks displaying an increasing trend were filtered from randomly fluctuating peaks using time trend ratios and Spearman's rank correlation coefficients. The first approach was successful in flagging model compounds spiked at only two to three time points, while the latter approach resulted in all model compounds ranking in the top 11 % of the peak lists. Compared to initial peak lists, a combination of both approaches reduced the size of datasets by 80-85 %. Overall, non-target time trend screening represents a promising data reduction strategy for identifying emerging bioaccumulative contaminants in biological samples. Graphical abstract

  9. High-resolution monochromator for iron nuclear resonance vibrational spectroscopy of biological samples

    Science.gov (United States)

    Yoda, Yoshitaka; Okada, Kyoko; Wang, Hongxin; Cramer, Stephen P.; Seto, Makoto

    2016-12-01

    A new high-resolution monochromator for 14.4-keV X-rays has been designed and developed for the Fe nuclear resonance vibrational spectroscopy of biological samples. In addition to high resolution, higher flux and stability are especially important for measuring biological samples, because of the very weak signals produced due to the low concentrations of Fe-57. A 24% increase in flux while maintaining a high resolution better than 0.9 meV is achieved in the calculation by adopting an asymmetric reflection of Ge, which is used as the first crystal of the three-bounce high-resolution monochromator. A 20% increase of the exit beam size is acceptable to our biological applications. The higher throughput of the new design has been experimentally verified. A fine rotation mechanics that combines a weak-link hinge with a piezoelectric actuator was used for controlling the photon energy of the monochromatic beam. The resulting stability is sufficient to preserve the intrinsic resolution.

  10. A review on determination of steroids in biological samples exploiting nanobio-electroanalytical methods.

    Science.gov (United States)

    Yadav, Saurabh K; Chandra, Pranjal; Goyal, Rajendra N; Shim, Yoon-Bo

    2013-01-31

    The applications of nanomaterial modified sensors, molecularly imprinting polymer based, aptamer based, and immunosensors have been described in the determination of steroids using electroanalytical techniques. After a brief description of the steroids and assays in biological fluids, the principles of electrochemical detection with the advantages and the limitations of the various sensors are presented. The nanomaterial modified sensors catalyze the oxidation/reduction of steroids and are suitable for sensing them in environmental samples and biological fluids. The determination of steroids based on their reduction has been found more useful in comparison to oxidation as the common metabolites present in the biological fluids do not undergo reduction in the usual potential window and hence, do not interfere in the determination. The sensors based on immunosensors and aptamers were found more sensitive and selective for steroid determination. Conducting polymer modified bio-sensors and microchip devices are suggested as possible future prospects for the ultra sensitive and simultaneous determination of steroids and their metabolites in various samples.

  11. The use of buccal cells in human biological monitoring

    Directory of Open Access Journals (Sweden)

    Ewa Błaszczyk

    2012-12-01

    Full Text Available One of the basic methods for determining the degree of environmental risk posed to humans is identification of harmful substances in various environmental elements (air, water, soil, food. In contrast to environmental monitoring human biological monitoring (HBM enables the estimation of an absorbed dose, general or localized in a specific organ. HBM enables the assessment of exposure to substances which are absorbed by the body via different exposure pathways and with different contaminant carriers. It is based on the measurement of indicators, the so-called biomarkers, in body fluids (blood, urine, saliva, etc. or in tissues and organs. Biomarkers can be divided into markers of exposure, effects and susceptibility. A particularly useful method is determination of adducts, i.e. carcinogenic compounds (or their metabolites with proteins or DNA, which are markers of exposure. Biomarkers of biological effects are different cytogenetic changes, including micronuclei. These are extranuclear structures containing fragments of chromatin (arising as a result of DNA breaks or whole chromosomes (damage to the spindle apparatus during mitosis. Up to now most studies on the DNA adduct levels and micronuclei have been conducted in peripheral lymphocytes. At present, studies using blood, especially in children to restricted to ethical aspects, and therefore tests using epithelial cells from the oral cavity have become more popular. Epithelial cells are the main building material of an epithelial tissue which makes up about 60% of all cells of the human body. The main function of the epithelial tissue is covering and lining of the outer and inner surfaces of the body. Epithelium underwent high specialisation in various parts of the human body, which is associated with its structure and function. Human oral cavity is covered by stratified squamous epithelium, which is comprised of cells called keratinocytes. Oral epithelial cells may differentiate in two

  12. Measurement of Beryllium in Biological Samples by Accelerator Mass Spectrometry: Applications for Studying Chronic Beryllium Disease

    Energy Technology Data Exchange (ETDEWEB)

    Chiarappa-Zucca, M L; Finkel, R C; Martinelli, R E; McAninch, J E; Nelson, D O; Turtletaub, K W

    2004-04-15

    A method using accelerator mass spectrometry (AMS) has been developed for quantifying attomoles of beryllium (Be) in biological samples. This method provides the sensitivity to trace Be in biological samples at very low doses with the purpose of identifying the molecular targets involved in chronic beryllium disease. Proof of the method was tested by administering 0.001, 0.05, 0.5 and 5.0 {micro}g {sup 9}Be and {sup 10}Be by intraperitoneal injection to male mice and removing spleen, liver, femurs, blood, lung, and kidneys after 24 h exposure. These samples were prepared for AMS analysis by tissue digestion in nitric acid, followed by further organic oxidation with hydrogen peroxide and ammonium persulfate and lastly, precipitation of Be with ammonium hydroxide, and conversion to beryllium oxide at 800 C. The {sup 10}Be/{sup 9}Be ratio of the extracted beryllium oxide was measured by AMS and Be in the original sample was calculated. Results indicate that Be levels were dose-dependent in all tissues and the highest levels were measured in the spleen and liver. The measured {sup 10}Be/{sup 9}Be ratios spanned 4 orders of magnitude, from 10{sup -10} to 10{sup -14}, with a detection limit of 3.0 x 10{sup -14}, which is equivalent to 0.8 attomoles of {sup 10}Be. These results show that routine quantification of nanogram levels of Be in tissues is possible and that AMS is a sensitive method that can be used in biological studies to understand the molecular dosimetry of Be and mechanisms of toxicity.

  13. Recombinant human thrombopoietin: basic biology and evaluation of clinical studies.

    Science.gov (United States)

    Kuter, David J; Begley, C Glenn

    2002-11-15

    Thrombocytopenia is a common medical problem for which the main treatment is platelet transfusion. Given the increasing use of platelets and the declining donor population, identification of a safe and effective platelet growth factor could improve the management of thrombocytopenia. Thrombopoietin (TPO), the c-Mpl ligand, is the primary physiologic regulator of megakaryocyte and platelet development. Since the purification of TPO in 1994, 2 recombinant forms of the c-Mpl ligand--recombinant human thrombopoietin (rhTPO) and pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF)--have undergone extensive clinical investigation. Both have been shown to be potent stimulators of megakaryocyte growth and platelet production and are biologically active in reducing the thrombocytopenia of nonmyeloablative chemotherapy. However, neither TPO has demonstrated benefit in stem cell transplantation or leukemia chemotherapy. Other clinical studies have investigated the use of TPO in treating chronic nonchemotherapy-induced thrombocytopenia associated with myelodysplastic syndromes, idiopathic thrombocytopenic purpura, thrombocytopenia due to human immunodeficiency virus, and liver disease. Based solely on animal studies, TPO may be effective in reducing surgical thrombocytopenia and bleeding, ex vivo expansion of pluripotent stem cells, and as a radioprotectant. Ongoing and future studies will help define the clinical role of recombinant TPO and TPO mimetics in the treatment of chemotherapy- and nonchemotherapy-induced thrombocytopenia.

  14. Spectrochemical analysis of powdered biological samples using transversely excited atmospheric carbon dioxide laser plasma excitation

    Science.gov (United States)

    Zivkovic, Sanja; Momcilovic, Milos; Staicu, Angela; Mutic, Jelena; Trtica, Milan; Savovic, Jelena

    2017-02-01

    The aim of this study was to develop a simple laser induced breakdown spectroscopy (LIBS) method for quantitative elemental analysis of powdered biological materials based on laboratory prepared calibration samples. The analysis was done using ungated single pulse LIBS in ambient air at atmospheric pressure. Transversely-Excited Atmospheric pressure (TEA) CO2 laser was used as an energy source for plasma generation on samples. The material used for the analysis was a blue-green alga Spirulina, widely used in food and pharmaceutical industries and also in a few biotechnological applications. To demonstrate the analytical potential of this particular LIBS system the obtained spectra were compared to the spectra obtained using a commercial LIBS system based on pulsed Nd:YAG laser. A single sample of known concentration was used to estimate detection limits for Ba, Ca, Fe, Mg, Mn, Si and Sr and compare detection power of these two LIBS systems. TEA CO2 laser based LIBS was also applied for quantitative analysis of the elements in powder Spirulina samples. Analytical curves for Ba, Fe, Mg, Mn and Sr were constructed using laboratory produced matrix-matched calibration samples. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used as the reference technique for elemental quantification, and reasonably well agreement between ICP and LIBS data was obtained. Results confirm that, in respect to its sensitivity and precision, TEA CO2 laser based LIBS can be successfully applied for quantitative analysis of macro and micro-elements in algal samples. The fact that nearly all classes of materials can be prepared as powders implies that the proposed method could be easily extended to a quantitative analysis of different kinds of materials, organic, biological or inorganic.

  15. Simple Sensitive Spectrophotometric Determination of Vanadium in Biological and Environmental Samples

    Directory of Open Access Journals (Sweden)

    B. Krishna Priya

    2006-01-01

    Full Text Available Novel, rapid, highly sensitive and selective spectrophotometric method for the determination of traces of vanadium (V in environmental and biological samples, pharmaceutical and steel samples was studied. The method is based on oxidation of 2,4- dinitro phenyl hydrazine(2,4-DNPH by vanadium (V followed by coupling reaction with N-(1-naphthalene-1-ylethane-1,2-diamine-dihydrochloride (NEDA in acidic medium to give red colored derivative or on oxidation of 4-Amino Pyridine by vanadium (V followed by coupling reaction with NEDA in basic medium to give pink colored derivative. The red colored derivative having an λmax 495 nm which is stable for 8 days and the pink colored derivative with 525 nm is stable for more than 7 days at 350C. Beer's law is obeyed for vanadium (V in the concentration range of 0.02 - 3.5 μg mL–1 (red derivative and 0.03 – 4.5 μg mL–1 (pink derivative at the wave length of maximum absorption. The optimum reaction conditions and other analytical parameters were investigated to enhance the sensitivity of the present method. The detailed study of various interferences made the method more selective. The proposed method was successfully applied to the analysis of vanadium in natural water samples, plant material, soil samples, synthetic mixtures, pharmaceutical samples and biological samples. The results obtained were agreed with the reported methods at the 95 % confidence level. The performance of proposed method was evaluated in terms of Student's t-test and Variance ratio f-test which indicates the significance of proposed method over reported method.

  16. Practical Guide to Using Cryoprotectants in Biological Sample Preparation at Cryogenic temperature for Electron Microscopic Studies

    Directory of Open Access Journals (Sweden)

    A-Reum Je

    2011-10-01

    Full Text Available Cryo-fixation enables the preservation of the fine structures of intracellular organelles in a condition that is as close to their native state as possible compared with chemical fixation and room temperature processing. Fixation is the initial step for biological sample preparation in electron microscopy. This step is critically important because the goals of electron microscopic observation are fundamentally dependent on well-preserved specimens resulting from this fixation. In the present work, key components of cryo-fixation, cryoprotectants, are tested with various cell types of interest. The results show that dextran can be easily adapted for use with animal cells and cyanobacteria, whereas 1-hexadecene is applicable to plant and yeast cells. The current report provides useful information on the preparation of cryo-fixed biological specimens using high pressure freezing and freeze-substitution aimed at electron microscopic observation.

  17. H2S Analysis in Biological Samples Using Gas Chromatography with Sulfur Chemiluminescence Detection

    Science.gov (United States)

    Vitvitsky, Victor; Banerjee, Ruma

    2015-01-01

    Hydrogen sulfide (H2S) is a metabolite and signaling molecule in biological tissues that regulates many physiological processes. Reliable and sensitive methods for H2S analysis are necessary for a better understanding of H2S biology and for the pharmacological modulation of H2S levels in vivo. In this chapter, we describe the use of gas chromatography coupled to sulfur chemiluminescence detection to measure the rates of H2S production and degradation by tissue homogenates at physiologically relevant concentrations of substrates. This method allows separation of H2S from other sulfur compounds and provides sensitivity of detection to ~15 pg (or 0.5 pmol) of H2S per injected sample. PMID:25725519

  18. Recognition of human face based on improved multi-sample

    Institute of Scientific and Technical Information of China (English)

    LIU Xia; LI Lei-lei; LI Ting-jun; LIU Lu; ZHANG Ying

    2009-01-01

    In order to solve the problem caused by variation illumination in human face recognition, we bring forward a face recognition algorithm based on the improved muhi-sample. In this algorithm, the face image is processed with Retinex theory, meanwhile, the Gabor filter is adopted to perform the feature extraction. The experimental results show that the application of Retinex theory improves the recognition accuracy, and makes the algorithm more robust to the variation illumination. The Gabor filter is more effective and accurate for extracting more useable facial local features. It is proved that the proposed algorithm has good recognition accuracy and it is stable under variation illumination.

  19. Evaluation of non-invasive biological samples to monitor Staphylococcus aureus colonization in great apes and lemurs.

    Directory of Open Access Journals (Sweden)

    Frieder Schaumburg

    Full Text Available INTRODUCTION: Reintroduction of endangered animals as part of conservational programs bears the risk of importing human pathogens from the sanctuary to the natural habitat. One bacterial pathogen that serves as a model organism to analyze this transmission is Staphylococcus aureus as it can colonize and infect both humans and animals. The aim of this study was to evaluate the utility of various biological samples to monitor S. aureus colonization in great apes and lemurs. METHODS: Mucosal swabs from wild lemurs (n=25, Kirindy, Madagascar, feces, oral and genital swabs from captive chimpanzees (n=58, Ngamba and Entebbe, Uganda and fruit wadges and feces from wild chimpanzees (n=21, Taï National Parc, Côte d'Ivoire were screened for S. aureus. Antimicrobial resistance and selected virulence factors were tested for each isolate. Sequence based genotyping (spa typing, multilocus sequence typing was applied to assess the population structure of S. aureus. RESULTS: Oro-pharyngeal carriage of S. aureus was high in lemurs (72%, n=18 and captive chimpanzees (69.2%, n=27 and 100%, n=6, respectively. Wild chimpanzees shed S. aureus through feces (43.8, n=7 and fruit wadges (54.5, n=12. Analysis of multiple sampling revealed that two samples are sufficient to detect those animals which shed S. aureus through feces or fruit wadges. Genotyping showed that captive animals are more frequently colonized with human-associated S. aureus lineages. CONCLUSION: Oro-pharyngeal swabs are useful to screen for S. aureus colonization in apes and lemurs before reintroduction. Duplicates of stool and fruit wadges reliably detect S. aureus shedding in wild chimpanzees. We propose to apply these sampling strategies in future reintroduction programs to screen for S. aureus colonization. They may also be useful to monitor S. aureus in wild populations.

  20. Surface-enhanced Raman scattering detection of silver nanoparticles in environmental and biological samples.

    Science.gov (United States)

    Guo, Huiyuan; Xing, Baoshan; Hamlet, Leigh C; Chica, Andrea; He, Lili

    2016-06-01

    Growing concerns over the potential release and threat of silver nanoparticles (AgNPs) to environmental and biological systems urge researchers to investigate their fate and behavior. However, current analytical techniques cannot meet the requirements for rapidly, sensitively and reliably probing AgNPs in complex matrices. Surface-enhanced Raman spectroscopy (SERS) has shown great capability for rapid detection of AgNPs based on an indicator molecule that can bind on the AgNP surface. The objective of this study was to exploit SERS to detect AgNPs in environmental and biological samples through optimizing the Raman indicator for SERS. Seven indicator molecules were selected and determined to obtain their SERS signals at optimal concentrations. Among them, 1,2-di(4-pyridyl)ethylene (BPE), crystal violet and ferric dimethyl-dithiocarbamate (ferbam) produced the highest SERS intensities. Further experiments on binding competition between each two of the three candidates showed that ferbam had the highest AgNPs-binding ability. The underlying mechanism lies in the strong binding affinity of ferbam with AgNPs via multiple sulfur atoms. We further validated ferbam to be an effective indicator for SERS detection of as low as 0.1mg/L AgNPs in genuine surface water and 0.57 mg/L in spinach juice. Moreover, limited interference on SERS detection of AgNPs was found from environmentally relevant inorganic ions, organic matter, inorganic particles, as well as biologically relevant components, demonstrating the ferbam-assisted SERS is an effective and sensitive method to detect AgNPs in complex environmental and biological samples.

  1. Modeling human risk: Cell & molecular biology in context

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    It is anticipated that early in the next century manned missions into outer space will occur, with a mission to Mars scheduled between 2015 and 2020. However, before such missions can be undertaken, a realistic estimation of the potential risks to the flight crews is required. One of the uncertainties remaining in this risk estimation is that posed by the effects of exposure to the radiation environment of outer space. Although the composition of this environment is fairly well understood, the biological effects arising from exposure to it are not. The reasons for this are three-fold: (1) A small but highly significant component of the radiation spectrum in outer space consists of highly charged, high energy (HZE) particles which are not routinely experienced on earth, and for which there are insufficient data on biological effects; (2) Most studies on the biological effects of radiation to date have been high-dose, high dose-rate, whereas in space, with the exception of solar particle events, radiation exposures will be low-dose, low dose-rate; (3) Although it has been established that the virtual absence of gravity in space has a profound effect on human physiology, it is not clear whether these effects will act synergistically with those of radiation exposure. A select panel will evaluate the utilizing experiments and models to accurately predict the risks associated with exposure to HZE particles. Topics of research include cellular and tissue response, health effects associated with radiation damage, model animal systems, and critical markers of Radiation response.

  2. Chromosome aberrations induced in human lymphocytes by U-235 fission neutrons: I. Irradiation of human blood samples in the "dry cell" of the TRIGA Mark II nuclear reactor.

    Science.gov (United States)

    Fajgelj, A; Lakoski, A; Horvat, D; Remec, I; Skrk, J; Stegnar, P

    1991-11-01

    A set-up for irradiation of biological samples in the TRIGA Mark II research reactor in Ljubljana is described. Threshold activation detectors were used for characterisation of the neutron flux, and the accompanying gamma dose was measured by TLDs. Human peripheral blood samples were irradiated "in vitro" and biological effects evaluated according to the unstable chromosomal aberrations induced. Biological effects of two types of cultivation of irradiated blood samples, the first immediately after irradiation and the second after 96 h storage, were studied. A significant difference in the incidence of chromosomal aberrations between these two types of samples was obtained, while our dose-response curve fitting coefficients alpha 1 = (7.71 +/- 0.09) x 10(-2) Gy-1 (immediate cultivation) and alpha 2 = (11.03 +/- 0.08) x 10(-2) Gy-1 (96 h delayed cultivation) are in both cases lower than could be found in the literature.

  3. Amino Nitrogen Quantum Dots-Based Nanoprobe for Fluorescence Detection and Imaging of Cysteine in Biological Samples.

    Science.gov (United States)

    Tang, Zhijiao; Lin, Zhenhua; Li, Gongke; Hu, Yuling

    2017-03-20

    Fluorescent amino nitrogen quantum dots (aN-dots) were synthesized by microwave-assisted method using 2-azidoimidazole and aqueous ammonia. The aN-dots have a nitrogen component up to 40%, which exhibit high fluorescence quantum yield, good photostability, and excellent biocompatibility. We further explored the use of the aN-dots combined with AuNPs as a nanoprobe for detecting fluorescently and imaging of cysteine (Cys) in complex biological samples. In this sensing system, the fluorescence of aN-dots was quenched significantly by gold nanoparticles (AuNPs), while the addition of Cys can lead to the fluorescence signal recovery. Furthermore, we have demonstrated that this strategy can offer a rapid and selective detection of Cys with a good linear relationship in the range of 0.3-3.0 μmol/L. As expected, this assay was successfully applied to the detection of Cys in human serum and plasma samples with recoveries ranging from 90.0% to 106.7%. Especially, the nanoprobe exhibits good cell membrane permeability and excellent biocompatibility by CCK-8 assay, which is favorable for bioimaging applications. Therefore, this fluorescent probe ensemble was further used for imaging of Cys in living cells, which suggests our proposed method has strong potential for clinical diagnosis. As a novel member of the quantum-dot family, the aN-dots hold great promise to broaden applications in biological systems.

  4. The scope of detector Medipix2 in micro-radiography of biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Dammer, J., E-mail: jiri.dammer@utef.cvut.cz [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ-12800 Prague 2 (Czech Republic); Weyda, F. [Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Entomology, Branisovska 31, CZ-37005 Ceske Budejovice (Czech Republic); Faculty of Science, University of South Bohemia, Branisovska 31, CZ-37005 Ceske Budejovice (Czech Republic); Jakubek, J. [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ-12800 Prague 2 (Czech Republic); Skrabal, P. [Faculty of Biomedical Engineering, Czech Technical University in Prague, Nam. Sitna 3105, CZ-272 01 Kladno (Czech Republic); Sopko, V.; Vavrik, D. [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ-12800 Prague 2 (Czech Republic)

    2011-05-15

    We present our experimental setup devoted to high resolution X-ray micro-radiography that is suitable for imaging of small biological samples. The photon source is a FeinFocus micro-focus X-ray tube. The single photon counting pixel device Medipix2 serves as imaging area. Recently used imaging detectors as radiography films or scintillator detectors, cannot visualize required information about inner structure of scanned sample. Detectors Medipix2 do not suffer from so-called dark current noise and work in unlimited dynamic range. These features of detectors confer high quality and high contrast of final images. The radiographic imaging with detectors Medipix2 represents non-invasive and non-destructive method of investigation. Hereby, we demonstrate results of micro-radiographic study of internal structures of tiny biological samples. In addition to morphological and anatomical studies, we would like to present preliminary study of dynamic processes inside of organisms using micro-radiographic video-capturing.

  5. Predicting brain structure in population-based samples with biologically informed genetic scores for schizophrenia.

    Science.gov (United States)

    Van der Auwera, Sandra; Wittfeld, Katharina; Shumskaya, Elena; Bralten, Janita; Zwiers, Marcel P; Onnink, A Marten H; Usberti, Niccolo; Hertel, Johannes; Völzke, Henry; Völker, Uwe; Hosten, Norbert; Franke, Barbara; Grabe, Hans J

    2017-04-01

    Schizophrenia is associated with brain structural abnormalities including gray and white matter volume reductions. Whether these alterations are caused by genetic risk variants for schizophrenia is unclear. Previous attempts to detect associations between polygenic factors for schizophrenia and structural brain phenotypes in healthy subjects have been negative or remain non-replicated. In this study, we used genetic risk scores that were based on the accumulated effect of selected risk variants for schizophrenia belonging to specific biological systems like synaptic function, neurodevelopment, calcium signaling, and glutamatergic neurotransmission. We hypothesized that this "biologically informed" approach would provide the missing link between genetic risk for schizophrenia and brain structural phenotypes. We applied whole-brain voxel-based morphometry (VBM) analyses in two population-based target samples and subsequent regions of interest (ROIs) analyses in an independent replication sample (total N = 2725). No consistent association between the genetic scores and brain volumes were observed in the investigated samples. These results suggest that in healthy subjects with a higher genetic risk for schizophrenia additional factors apart from common genetic variants (e.g., infection, trauma, rare genetic variants, or gene-gene interactions) are required to induce structural abnormalities of the brain. Further studies are recommended to test for possible gene-gene or gene-environment effects. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. Surface-enhanced Raman scattering detection of silver nanoparticles in environmental and biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Huiyuan [Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States); Xing, Baoshan, E-mail: bx@umass.edu [Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States); Hamlet, Leigh C.; Chica, Andrea [Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States); He, Lili, E-mail: lilihe@foodsci.umass.edu [Department of Food Science, University of Massachusetts, Amherst, MA 01003 (United States)

    2016-06-01

    Growing concerns over the potential release and threat of silver nanoparticles (AgNPs) to environmental and biological systems urge researchers to investigate their fate and behavior. However, current analytical techniques cannot meet the requirements for rapidly, sensitively and reliably probing AgNPs in complex matrices. Surface-enhanced Raman spectroscopy (SERS) has shown great capability for rapid detection of AgNPs based on an indicator molecule that can bind on the AgNP surface. The objective of this study was to exploit SERS to detect AgNPs in environmental and biological samples through optimizing the Raman indicator for SERS. Seven indicator molecules were selected and determined to obtain their SERS signals at optimal concentrations. Among them, 1,2-di(4-pyridyl)ethylene (BPE), crystal violet and ferric dimethyl-dithiocarbamate (ferbam) produced the highest SERS intensities. Further experiments on binding competition between each two of the three candidates showed that ferbam had the highest AgNPs-binding ability. The underlying mechanism lies in the strong binding affinity of ferbam with AgNPs via multiple sulfur atoms. We further validated ferbam to be an effective indicator for SERS detection of as low as 0.1 mg/L AgNPs in genuine surface water and 0.57 mg/L in spinach juice. Moreover, limited interference on SERS detection of AgNPs was found from environmentally relevant inorganic ions, organic matter, inorganic particles, as well as biologically relevant components, demonstrating the ferbam-assisted SERS is an effective and sensitive method to detect AgNPs in complex environmental and biological samples. - Graphical abstract: SERS signal intensity of ferbam indicates the concentration of AgNPs. - Highlights: • Ferbam was found to be the best indicator for SERS detection of AgNPs. • SERS was able to detect AgNPs in both environmental and biological samples. • Major components in the two matrices had limited effect on AgNP detection.

  7. Human papillomavirus detection from human immunodeficiency virus-infected Colombian women's paired urine and cervical samples.

    Science.gov (United States)

    Munoz, Marina; Camargo, Milena; Soto-De Leon, Sara C; Sanchez, Ricardo; Parra, Diana; Pineda, Andrea C; Sussmann, Otto; Perez-Prados, Antonio; Patarroyo, Manuel E; Patarroyo, Manuel A

    2013-01-01

    Infection, coinfection and type-specific human papillomavirus (HPV) distribution was evaluated in human immunodeficiency virus (HIV)-positive women from paired cervical and urine samples. Paired cervical and urine samples (n = 204) were taken from HIV-positive women for identifying HPV-DNA presence by using polymerase chain reaction (PCR) with three generic primer sets (GP5+/6+, MY09/11 and pU1M/2R). HPV-positive samples were typed for six high-risk HPV (HR-HPV) (HPV-16, -18, -31, -33, -45 and -58) and two low-risk (LR-HPV) (HPV-6/11) types. Agreement between paired sample results and diagnostic performance was evaluated. HPV infection prevalence was 70.6% in cervical and 63.2% in urine samples. HPV-16 was the most prevalent HPV type in both types of sample (66.7% in cervical samples and 62.0% in urine) followed by HPV-31(47.2%) in cervical samples and HPV-58 (35.7%) in urine samples. There was 55.4% coinfection (infection by more than one type of HPV) in cervical samples and 40.2% in urine samples. Abnormal Papanicolau smears were observed in 25.3% of the women, presenting significant association with HPV-DNA being identified in urine samples. There was poor agreement of cervical and urine sample results in generic and type-specific detection of HPV. Urine samples provided the best diagnosis when taking cytological findings as reference. In conclusion including urine samples could be a good strategy for ensuring adherence to screening programs aimed at reducing the impact of cervical cancer, since this sample is easy to obtain and showed good diagnostic performance.

  8. Human papillomavirus detection from human immunodeficiency virus-infected Colombian women's paired urine and cervical samples.

    Directory of Open Access Journals (Sweden)

    Marina Munoz

    Full Text Available Infection, coinfection and type-specific human papillomavirus (HPV distribution was evaluated in human immunodeficiency virus (HIV-positive women from paired cervical and urine samples. Paired cervical and urine samples (n = 204 were taken from HIV-positive women for identifying HPV-DNA presence by using polymerase chain reaction (PCR with three generic primer sets (GP5+/6+, MY09/11 and pU1M/2R. HPV-positive samples were typed for six high-risk HPV (HR-HPV (HPV-16, -18, -31, -33, -45 and -58 and two low-risk (LR-HPV (HPV-6/11 types. Agreement between paired sample results and diagnostic performance was evaluated. HPV infection prevalence was 70.6% in cervical and 63.2% in urine samples. HPV-16 was the most prevalent HPV type in both types of sample (66.7% in cervical samples and 62.0% in urine followed by HPV-31(47.2% in cervical samples and HPV-58 (35.7% in urine samples. There was 55.4% coinfection (infection by more than one type of HPV in cervical samples and 40.2% in urine samples. Abnormal Papanicolau smears were observed in 25.3% of the women, presenting significant association with HPV-DNA being identified in urine samples. There was poor agreement of cervical and urine sample results in generic and type-specific detection of HPV. Urine samples provided the best diagnosis when taking cytological findings as reference. In conclusion including urine samples could be a good strategy for ensuring adherence to screening programs aimed at reducing the impact of cervical cancer, since this sample is easy to obtain and showed good diagnostic performance.

  9. High resolution x-ray microtomography of biological samples: Requirements and strategies for satisfying them

    Energy Technology Data Exchange (ETDEWEB)

    Loo, B.W. Jr. [Univ. of California, San Francisco, CA (United States)]|[Univ. of California, Davis, CA (United States)]|[Lawrence Berkeley National Lab., CA (United States); Rothman, S.S. [Univ. of California, San Francisco, CA (United States)]|[Lawrence Berkeley National Lab., CA (United States)

    1997-02-01

    High resolution x-ray microscopy has been made possible in recent years primarily by two new technologies: microfabricated diffractive lenses for soft x-rays with about 30-50 nm resolution, and high brightness synchrotron x-ray sources. X-ray microscopy occupies a special niche in the array of biological microscopic imaging methods. It extends the capabilities of existing techniques mainly in two areas: a previously unachievable combination of sub-visible resolution and multi-micrometer sample size, and new contrast mechanisms. Because of the soft x-ray wavelengths used in biological imaging (about 1-4 nm), XM is intermediate in resolution between visible light and electron microscopies. Similarly, the penetration depth of soft x-rays in biological materials is such that the ideal sample thickness for XM falls in the range of 0.25 - 10 {mu}m, between that of VLM and EM. XM is therefore valuable for imaging of intermediate level ultrastructure, requiring sub-visible resolutions, in intact cells and subcellular organelles, without artifacts produced by thin sectioning. Many of the contrast producing and sample preparation techniques developed for VLM and EM also work well with XM. These include, for example, molecule specific staining by antibodies with heavy metal or fluorescent labels attached, and sectioning of both frozen and plastic embedded tissue. However, there is also a contrast mechanism unique to XM that exists naturally because a number of elemental absorption edges lie in the wavelength range used. In particular, between the oxygen and carbon absorption edges (2.3 and 4.4 nm wavelength), organic molecules absorb photons much more strongly than does water, permitting element-specific imaging of cellular structure in aqueous media, with no artifically introduced contrast agents. For three-dimensional imaging applications requiring the capabilities of XM, an obvious extension of the technique would therefore be computerized x-ray microtomography (XMT).

  10. 3D nanoscale imaging of biological samples with laboratory-based soft X-ray sources

    Science.gov (United States)

    Dehlinger, Aurélie; Blechschmidt, Anne; Grötzsch, Daniel; Jung, Robert; Kanngießer, Birgit; Seim, Christian; Stiel, Holger

    2015-09-01

    In microscopy, where the theoretical resolution limit depends on the wavelength of the probing light, radiation in the soft X-ray regime can be used to analyze samples that cannot be resolved with visible light microscopes. In the case of soft X-ray microscopy in the water-window, the energy range of the radiation lies between the absorption edges of carbon (at 284 eV, 4.36 nm) and oxygen (543 eV, 2.34 nm). As a result, carbon-based structures, such as biological samples, posses a strong absorption, whereas e.g. water is more transparent to this radiation. Microscopy in the water-window, therefore, allows the structural investigation of aqueous samples with resolutions of a few tens of nanometers and a penetration depth of up to 10μm. The development of highly brilliant laser-produced plasma-sources has enabled the transfer of Xray microscopy, that was formerly bound to synchrotron sources, to the laboratory, which opens the access of this method to a broader scientific community. The Laboratory Transmission X-ray Microscope at the Berlin Laboratory for innovative X-ray technologies (BLiX) runs with a laser produced nitrogen plasma that emits radiation in the soft X-ray regime. The mentioned high penetration depth can be exploited to analyze biological samples in their natural state and with several projection angles. The obtained tomogram is the key to a more precise and global analysis of samples originating from various fields of life science.

  11. Multiple replica repulsion technique for efficient conformational sampling of biological systems.

    Science.gov (United States)

    Malevanets, Anatoly; Wodak, Shoshana J

    2011-08-17

    Here, we propose a technique for sampling complex molecular systems with many degrees of freedom. The technique, termed "multiple replica repulsion" (MRR), does not suffer from poor scaling with the number of degrees of freedom associated with common replica exchange procedures and does not require sampling at high temperatures. The algorithm involves creation of multiple copies (replicas) of the system, which interact with one another through a repulsive potential that can be applied to the system as a whole or to portions of it. The proposed scheme prevents oversampling of the most populated states and provides accurate descriptions of conformational perturbations typically associated with sampling ground-state energy wells. The performance of MRR is illustrated for three systems of increasing complexity. A two-dimensional toy potential surface is used to probe the sampling efficiency as a function of key parameters of the procedure. MRR simulations of the Met-enkephalin pentapeptide, and the 76-residue protein ubiquitin, performed in presence of explicit water molecules and totaling 32 ns each, investigate the ability of MRR to characterize the conformational landscape of the peptide, and the protein native basin, respectively. Results obtained for the enkephalin peptide reflect more closely the extensive conformational flexibility of this peptide than previously reported simulations. Those obtained for ubiquitin show that conformational ensembles sampled by MRR largely encompass structural fluctuations relevant to biological recognition, which occur on the microsecond timescale, or are observed in crystal structures of ubiquitin complexes with other proteins. MRR thus emerges as a very promising simple and versatile technique for modeling the structural plasticity of complex biological systems. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  12. Magnetic induction spectroscopy: non-contact measurement of the electrical conductivity spectra of biological samples

    Science.gov (United States)

    Barai, A.; Watson, S.; Griffiths, H.; Patz, R.

    2012-08-01

    Measurement of the electrical conductivity of biological tissues as a function of frequency, often termed ‘bioelectrical impedance spectroscopy (BIS)’, provides valuable information on tissue structure and composition. In implementing BIS though, there can be significant practical difficulties arising from the electrode-sample interface which have likely limited its deployment in industrial applications. In magnetic induction spectroscopy (MIS) these difficulties are eliminated through the use of fully non-contacting inductive coupling between the sensors and sample. However, inductive coupling introduces its own set of technical difficulties, primarily related to the small magnitudes of the induced currents and their proportionality with frequency. This paper describes the design of a practical MIS system incorporating new, highly-phase-stable electronics and compares its performance with that of electrode-based BIS in measurements on biological samples including yeast suspensions in saline (concentration 50-400 g l-1) and solid samples of potato, cucumber, tomato, banana and porcine liver. The shapes of the MIS spectra were in good agreement with those for electrode-based BIS, with a residual maximum discrepancy of 28%. The measurement precision of the MIS was 0.05 S m-1 at 200 kHz, improving to 0.01 S m-1 at a frequency of 20 MHz, for a sample volume of 80 ml. The data-acquisition time for each MIS measurement was 52 s. Given the value of spectroscopic conductivity information and the many advantages of obtaining these data in a non-contacting manner, even through electrically-insulating packaging materials if necessary, it is concluded that MIS is a technique with considerable potential for monitoring bio-industrial processes and product quality.

  13. The correlation of arsenic levels in drinking water with the biological samples of skin disorders

    Energy Technology Data Exchange (ETDEWEB)

    Kazi, Tasneem Gul [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: tgkazi@yahoo.com; Arain, Muhammad Balal [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: bilal_ku2004@yahoo.com; Baig, Jameel Ahmed [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: jab_mughal@yahoo.com; Jamali, Muhammad Khan [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: mkhanjamali@yahoo.com; Afridi, Hassan Imran [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: hassanimranafridi@yahoo.com; Jalbani, Nusrat [Pakistan Council for Scientific and Industrial Research, University Road Karachi-75280 (Pakistan)], E-mail: nusratjalbani_21@yahoo.com; Sarfraz, Raja Adil [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: rajaadilsarfraz@gmail.com; Shah, Abdul Qadir [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: aqshah07@yahoo.com; Niaz, Abdul [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: niazchemist2k6@yahoo.com

    2009-01-15

    Arsenic (As) poisoning has become a worldwide public health concern. The skin is quite sensitive to As and skin lesions are the most common and earliest nonmalignant effects associated to chronic As exposure. In 2005-2007, a survey was carried out on surface and groundwater arsenic contamination and relationships between As exposure via the drinking water and related adverse health effects (melanosis and keratosis) on villagers resides on the banks of Manchar lake, southern part of Sindh, Pakistan. We screened the population from arsenic-affected villages, 61 to 73% population were identified patients suffering from chronic arsenic toxicity. The effects of As toxicity via drinking water were estimated by biological samples (scalp hair and blood) of adults (males and females), have or have not skin problem (n = 187). The referent samples of both genders were also collected from the areas having low level of As (< 10 {mu}g/L) in drinking water (n = 121). Arsenic concentration in drinking water and biological samples were analyzed using electrothermal atomic absorption spectrometry. The range of arsenic concentrations in lake surface water was 35.2-158 {mu}g/L, which is 3-15 folds higher than World Health Organization [WHO, 2004. Guidelines for drinking-water quality third ed., WHO Geneva Switzerland.]. It was observed that As concentration in the scalp hair and blood samples were above the range of permissible values 0.034-0.319 {mu}g As/g for hair and < 0.5-4.2 {mu}g/L for blood. The linear regressions showed good correlations between arsenic concentrations in water versus hair and blood samples of exposed skin diseased subjects (R{sup 2} = 0.852 and 0.718) as compared to non-diseased subjects (R{sup 2} = 0.573 and 0.351), respectively.

  14. Electrophoresis tests on STS-3 and ground control experiments - A basis for future biological sample selections

    Science.gov (United States)

    Morrison, D. R.; Lewis, M. L.

    1982-01-01

    Static zone electrophoresis is an electrokinetic method of separating macromolecules and small particles. However, its application for the isolation of biological cells and concentrated protein solutions is limited by sedimentation and convection. Microgravity eliminates or reduces sedimentation, floatation, and density-driven convection arising from either Joule heating or concentration differences. The advantages of such an environment were first demonstrated in space during the Apollo 14 and 16 missions. In 1975 the Electrophoresis Technology Experiment (MA-011) was conducted during the Apollo-Soyuz Test Project flight. In 1979 a project was initiated to repeat the separations of human kidney cells. One of the major objectives of the Electrophoresis Equipment Verification Tests (EEVT) on STS-3 was to repeat and thereby validate the first successful electrophoretic separation of human kidney cells. Attention is given to the EEVT apparatus, the preflight electrophoresis, and inflight operational results.

  15. Non-destructive high-resolution thermal imaging techniques to evaluate wildlife and delicate biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Lavers, C; Franklin, P; Franklin, P; Plowman, A; Sayers, G; Bol, J; Shepard, D; Fields, D, E-mail: brnc-radarcomms1@nrta.mod.u [Sensors Team, Plymouth University at Britannia Royal Naval College, Dartmouth, Devon (United Kingdom) and Paignton Zoological Park, Paignton, Devon (United Kingdom); Thermal Wave Imaging, Inc., 845 Livernoise St, Ferndale, MI (United States); Buckfast Butterfly and Otter Sanctuary, Buckfast, Devon (United Kingdom)

    2009-07-01

    Thermal imaging cameras now allows routine monitoring of dangerous yet endangered wildlife in captivity. This study looks at the potential applications of radiometrically calibrated thermal data to wildlife, as well as providing parameters for future materials applications. We present a non-destructive active testing technique suitable for enhancing imagery contrast of thin or delicate biological specimens yielding improved thermal contrast at room temperature, for analysis of sample thermal properties. A broad spectrum of animals is studied with different textured surfaces, reflective and emissive properties in the infra red part of the electromagnetic spectrum. Some surface features offer biomimetic materials design opportunities.

  16. Selective extraction of proteins and other macromolecules from biological samples using molecular imprinted polymers.

    Science.gov (United States)

    Stevenson, Derek; El-Sharif, Hazim F; Reddy, Subrayal M

    2016-11-01

    The accurate determination of intact macromolecules in biological samples, such as blood, plasma, serum, urine, tissue and feces is a challenging problem. The increased interest in macromolecules both as candidate drugs and as biomarkers for diagnostic purposes means that new method development approaches are needed. This review charts developments in the use of molecularly imprinted polymers first for small-molecular-mass compounds then for proteins and other macromolecules. Examples of the development of molecularly imprinted polymers for macromolecules are highlighted. The two main application areas to date are sensors and separation science, particularly SPE. Examples include peptides and polypeptides, lysozyme, hemoglobin, ovalbumin, bovine serum albumin and viruses.

  17. Evaluation of Botanical Reference Materials for the Determination of Vanadium in Biological Samples

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Damsgaard, Else

    1982-01-01

    Three botanical reference materials prepared by the National Bureau of Standards have been studied by neutron activation analysis to evaluate their suitability with respect to the determination of vanadium in biological samples. Various decomposition methods were applied in connection with chemic....... A reference value of 1.15 mg/kg of this material is recommended, based on results from 3 different methods. All three materials are preferable to SRM 1571 Orchard Leaves, while Bowen's Kale remains the material of choice because of its lower concentration....

  18. Spectrophotometric assay of creatinine in human serum sample

    Directory of Open Access Journals (Sweden)

    Avinash Krishnegowda

    2017-05-01

    Full Text Available A new spectrophotometric method for the analysis of creatinine concentration in human serum samples is developed. The method explores the oxidation of p-methylamino phenol sulfate (Metol in the presence of copper sulfate and creatinine which yields an intense violet colored species with maximum absorbance at 530 nm. The calibration graph of creatinine by fixed time assay ranged from 4.4 to 620 μM. Recovery of creatinine in human serum samples varied from 101% to 106%. Limit of detection and limit of quantification were 0.145 μM and 0.487 μM respectively. Sandell’s sensitivity was 0.112 μg cm−2 and molar absorptivity was 0.101 × 104 L mol−1 cm−1. Within day precision was 2.5–4.8% and day-to-day precision range was 3.2–7.8%. The robustness and ruggedness of the method expressed in RSD values ranged from 0.78% to 2.12% and 1.32% to 3.46% respectively, suggesting that the developed method was rugged. This method provides good sensitivity and is comparable to standard Jaffe’s method with comparatively less interference from foreign substances.

  19. Rapid extraction and preservation of genomic DNA from human samples.

    Science.gov (United States)

    Kalyanasundaram, D; Kim, J-H; Yeo, W-H; Oh, K; Lee, K-H; Kim, M-H; Ryew, S-M; Ahn, S-G; Gao, D; Cangelosi, G A; Chung, J-H

    2013-02-01

    Simple and rapid extraction of human genomic DNA remains a bottleneck for genome analysis and disease diagnosis. Current methods using microfilters require cumbersome, multiple handling steps in part because salt conditions must be controlled for attraction and elution of DNA in porous silica. We report a novel extraction method of human genomic DNA from buccal swab and saliva samples. DNA is attracted onto a gold-coated microchip by an electric field and capillary action while the captured DNA is eluted by thermal heating at 70 °C. A prototype device was designed to handle four microchips, and a compatible protocol was developed. The extracted DNA using microchips was characterized by qPCR for different sample volumes, using different lengths of PCR amplicon, and nuclear and mitochondrial genes. In comparison with a commercial kit, an equivalent yield of DNA extraction was achieved with fewer steps. Room-temperature preservation for 1 month was demonstrated for captured DNA, facilitating straightforward collection, delivery, and handling of genomic DNA in an environment-friendly protocol.

  20. FANTOM5 CAGE profiles of human and mouse samples

    KAUST Repository

    Noguchi, Shuhei

    2017-08-29

    In the FANTOM5 project, transcription initiation events across the human and mouse genomes were mapped at a single base-pair resolution and their frequencies were monitored by CAGE (Cap Analysis of Gene Expression) coupled with single-molecule sequencing. Approximately three thousands of samples, consisting of a variety of primary cells, tissues, cell lines, and time series samples during cell activation and development, were subjected to a uniform pipeline of CAGE data production. The analysis pipeline started by measuring RNA extracts to assess their quality, and continued to CAGE library production by using a robotic or a manual workflow, single molecule sequencing, and computational processing to generate frequencies of transcription initiation. Resulting data represents the consequence of transcriptional regulation in each analyzed state of mammalian cells. Non-overlapping peaks over the CAGE profiles, approximately 200,000 and 150,000 peaks for the human and mouse genomes, were identified and annotated to provide precise location of known promoters as well as novel ones, and to quantify their activities.

  1. On-line Determination of Zinc in Water and Biological Samples after Its Preconcentration onto Zincon Anchored Polyurethane Foam.

    Science.gov (United States)

    Azeem, Sami M Abdel; Hanafi, Hassan A; El-Shahat, M F

    2015-01-01

    A fast and sensitive on-line procedure for the determination of zinc in water and biological samples was developed. Zinc was preconcentrated in a mini-column packed with polyurethane foam (PUF) chemically modified with zincon via -N=N- bonding. The optimal conditions for preconcentration were pH 8.5 and sample flow rate of 4.0 mL min(-1). Quantitative desorption of Zn(II) was obtained by 0.1 mol L(-1) hydrochloric acid and subsequent spectrophotmetric determination using 4-(2-pyridylazo)-resorcinol at 498 nm. The obtained detection limit was found to be 3.0 ng mL(-1), precision (RSD) was 4.8 and 6.7% at 20 and 110 ng mL(-1), respectively, for 60 s preconcentration time and enrichment factor was 31. The linearity range was from 10 to 120 ng mL(-1) and maximum sample throughput was 20 h(-1). Finally, the method was successfully applied to the determination of zinc in tap water, Nile River water and human urine samples with RSD in the range of 1.1 - 8.3%.

  2. A percutaneous needle biopsy technique for sampling the supraclavicular brown adipose tissue depot of humans.

    Science.gov (United States)

    Chondronikola, M; Annamalai, P; Chao, T; Porter, C; Saraf, M K; Cesani, F; Sidossis, L S

    2015-10-01

    Brown adipose tissue (BAT) has been proposed as a potential target tissue against obesity and its related metabolic complications. Although the molecular and functional characteristics of BAT have been intensively studied in rodents, only a few studies have used human BAT specimens due to the difficulty of sampling human BAT deposits. We established a novel positron emission tomography and computed tomography-guided Bergström needle biopsy technique to acquire human BAT specimens from the supraclavicular area in human subjects. Forty-three biopsies were performed on 23 participants. The procedure was tolerated well by the majority of participants. No major complications were noted. Numbness (9.6%) and hematoma (2.3%) were the two minor complications noted, which fully resolved. Thus, the proposed biopsy technique can be considered safe with only minimal risk of adverse events. Adoption of the proposed method is expected to increase the sampling of the supraclavicular BAT depot for research purposes so as to augment the scientific knowledge of the biology of human BAT.

  3. Quantification of Human Kallikrein-Related Peptidases in Biological Fluids by Multiplatform Targeted Mass Spectrometry Assays.

    Science.gov (United States)

    Karakosta, Theano D; Soosaipillai, Antoninus; Diamandis, Eleftherios P; Batruch, Ihor; Drabovich, Andrei P

    2016-09-01

    Human kallikrein-related peptidases (KLKs) are a group of 15 secreted serine proteases encoded by the largest contiguous cluster of protease genes in the human genome. KLKs are involved in coordination of numerous physiological functions including regulation of blood pressure, neuronal plasticity, skin desquamation, and semen liquefaction, and thus represent promising diagnostic and therapeutic targets. Until now, quantification of KLKs in biological and clinical samples was accomplished by enzyme-linked immunosorbent assays (ELISA). Here, we developed multiplex targeted mass spectrometry assays for the simultaneous quantification of all 15 KLKs. Proteotypic peptides for each KLK were carefully selected based on experimental data and multiplexed in single assays. Performance of assays was evaluated using three different mass spectrometry platforms including triple quadrupole, quadrupole-ion trap, and quadrupole-orbitrap instruments. Heavy isotope-labeled synthetic peptides with a quantifying tag were used for absolute quantification of KLKs in sweat, cervico-vaginal fluid, seminal plasma, and blood serum, with limits of detection ranging from 5 to 500 ng/ml. Analytical performance of assays was evaluated by measuring endogenous KLKs in relevant biological fluids, and results were compared with selected ELISAs. The multiplex targeted proteomic assays were demonstrated to be accurate, reproducible, sensitive, and specific alternatives to antibody-based assays. Finally, KLK4, a highly prostate-specific protein and a speculated biomarker of prostate cancer, was unambiguously detected and quantified by immunoenrichment-SRM assay in seminal plasma and blood serum samples from individuals with confirmed prostate cancer and negative biopsy. Mass spectrometry revealed exclusively the presence of a secreted isoform and thus unequivocally resolved earlier disputes about KLK4 identity in seminal plasma. Measurements of KLK4 in either 41 seminal plasma or 58 blood serum samples

  4. Sample sizing of biological materials analyzed by energy dispersion X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Jose D.S.; Franca, Elvis J.; Magalhaes, Marcelo R.L.; Almeida, Marcio E.S.; Hazin, Clovis A., E-mail: dan-paiva@hotmail.com, E-mail: ejfranca@cnen.gov.br, E-mail: marcelo_rlm@hotmail.com, E-mail: maensoal@yahoo.com.br, E-mail: chazin@cnen.gov.b [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2013-07-01

    Analytical portions used in chemical analyses are usually less than 1g. Errors resulting from the sampling are barely evaluated, since this type of study is a time-consuming procedure, with high costs for the chemical analysis of large number of samples. The energy dispersion X-ray fluorescence - EDXRF is a non-destructive and fast analytical technique with the possibility of determining several chemical elements. Therefore, the aim of this study was to provide information on the minimum analytical portion for quantification of chemical elements in biological matrices using EDXRF. Three species were sampled in mangroves from the Pernambuco, Brazil. Tree leaves were washed with distilled water, oven-dried at 60 deg C and milled until 0.5 mm particle size. Ten test-portions of approximately 500 mg for each species were transferred to vials sealed with polypropylene film. The quality of the analytical procedure was evaluated from the reference materials IAEA V10 Hay Powder, SRM 2976 Apple Leaves. After energy calibration, all samples were analyzed under vacuum for 100 seconds for each group of chemical elements. The voltage used was 15 kV and 50 kV for chemical elements of atomic number lower than 22 and the others, respectively. For the best analytical conditions, EDXRF was capable of estimating the sample size uncertainty for further determination of chemical elements in leaves. (author)

  5. Biological and biomedical (14)C-accelerator mass spectrometry and graphitization of carbonaceous samples.

    Science.gov (United States)

    Chung, Ill-Min; Kim, Seung-Hyun

    2013-06-21

    Accelerator mass spectrometry (AMS) is the ultimate technique for measuring rare isotopes in small samples. Biological and biomedical applications of (14)C-AMS (bio-(14)C-AMS) commenced in the early 1990s and are now widely used in many research fields including pharmacology, toxicology, food, and nutrition. For accurate, precise, and reproducible bio-(14)C-AMS analysis, the graphitization step in sample preparation is the most critical step. So, various sample preparation methods for a process called graphitization have been reported for specific applications. Catalytic graphitization using either a flame-sealed borosilicate tube or a septa-sealed vial is a popular sample preparation method for bio-(14)C-AMS. In this review, we introduce the AMS system, especially for bio-(14)C-AMS. In addition, we also review the graphitization method for bio-(14)C-AMS to promote further understanding and improvement of sample preparation for this technique. Examples of catalytic graphitization methods over the past two decades are described.

  6. Isolation of Cancer Stem Cells From Human Prostate Cancer Samples

    Science.gov (United States)

    Vidal, Samuel J.; Quinn, S. Aidan; de la Iglesia-Vicente, Janis; Bonal, Dennis M.; Rodriguez-Bravo, Veronica; Firpo-Betancourt, Adolfo; Cordon-Cardo, Carlos; Domingo-Domenech, Josep

    2014-01-01

    The cancer stem cell (CSC) model has been considerably revisited over the last two decades. During this time CSCs have been identified and directly isolated from human tissues and serially propagated in immunodeficient mice, typically through antibody labeling of subpopulations of cells and fractionation by flow cytometry. However, the unique clinical features of prostate cancer have considerably limited the study of prostate CSCs from fresh human tumor samples. We recently reported the isolation of prostate CSCs directly from human tissues by virtue of their HLA class I (HLAI)-negative phenotype. Prostate cancer cells are harvested from surgical specimens and mechanically dissociated. A cell suspension is generated and labeled with fluorescently conjugated HLAI and stromal antibodies. Subpopulations of HLAI-negative cells are finally isolated using a flow cytometer. The principal limitation of this protocol is the frequently microscopic and multifocal nature of primary cancer in prostatectomy specimens. Nonetheless, isolated live prostate CSCs are suitable for molecular characterization and functional validation by transplantation in immunodeficient mice. PMID:24686446

  7. Phylogenetic analysis of Escherichia coli strains isolated from human samples

    Directory of Open Access Journals (Sweden)

    Abdollah Derakhshandeh

    2013-12-01

    Full Text Available Escherichia coli (E. coli is a normal inhabitant of the gastrointestinal tract of vertebrates, including humans. Phylogenetic analysis has shown that E. coli is composed of four main phylogenetic groups (A, B1, B2 and D. Group A and B1 are generally associated with commensals, whereas group B2 is associated with extra-intestinal pathotypes. Most enteropathogenic isolates, however, are assigned to group D. In the present study, a total of 102 E. coli strains, isolated from human samples, were used. Phylogenetic grouping was done based on the Clermont triplex PCR method using primers targeted at three genetic markers, chuA, yjaA and TspE4.C2. Group A contained the majority of the collected isolates (69 isolates, 67.64%, followed by group B2 (18 isolates, 17.64% and D (15 isolates, 14.7% and no strains were found to belong to group B1. The distribution of phylogenetic groups in our study suggests that although the majority of strains were commensals, the prevalence of enteropathogenic and extra-intestinal pathotypes was noteworthy. Therefore, the role of E. coli in human infections including diarrhea, urinary tract infections and meningitis should be considered.

  8. A round-robin determination of boron in botanical and biological samples.

    Science.gov (United States)

    Downing, R G; Strong, P L

    1998-01-01

    The accurate determination of boron (B) at trace and ultratrace concentrations is an important step toward establishing the role of B in biological functions. However, low-level B concentrations are difficult to determine accurately, especially for many botanical and biological matrices. A round-robin study was conducted to assess analytical agreement for low-level B determinations. Ten experienced research groups from analytical laboratories extending across Europe, Asia, and the US participated in this study. These groups represent a cross-section of academic, commercial, and government facilities. The researchers employed both ion-coupled plasma and neutron techniques in the study. Results from this round-robin study indicate good agreement between participating laboratories at the mg/kg level, but at the lowest levels, microg/kg, only three laboratories participated, and agreement was poor. By encouraging discussion among scientists over these data, the secondary goal of this round-robin study is to stimulate continued improvement in analytical procedures and techniques for accurate low-level B determinations. Furthermore, it is intended to encourage the development of a variety of low-level (low mg/kg and microg/kg) B certified reference samples in biological and botanical matrices. The results from the round-robin analyses were compiled and are summarized in this article.

  9. Proton Transmitting Energy Spectra and Transmission Electron Microscope Examinations of Biological Samples

    Science.gov (United States)

    Tan, Chun-yu; Xia, Yue-yuan; Zhang, Jian-hua; Mu, Yu-guang; Wang, Rui-jin; Liu, Ji-tian; Liu, Xiang-dong; Yu, Zeng-liang

    1999-02-01

    Transmission energy spectra of 530 keV H+ ion penetrating 140 μm thick seed coat of maize and fruit peel of grape with thickness of 100 μm were measured. The result indicates that these thick biological targets, as seen by the penetrating ions, are inhomogeneous, and there are open "channel like" paths along which the incident ions can transmit the targets easily. While most of the incident ions are stopped in the targets, some of the transmitting ions only lose a small fraction of their initial incident energy. The transmission energy spectra show a pure electronic stopping feature. Transmission electron microscope (TEM) micrographes taken from the samples of seed coat of maize and fruit peel of tomato with thickness of 60 μm indicate that 150 keV electron beam from the TEM can penetrate the thick samples to give very good images with clear contrasts.

  10. Phytochemical analysis and biological evaluation of selected African propolis samples from Cameroon and Congo.

    Science.gov (United States)

    Papachroni, Danai; Graikou, Konstantia; Kosalec, Ivan; Damianakos, Harilaos; Ingram, Verina; Chinou, Ioanna

    2015-01-01

    The objective of this study was the chemical analysis of four selected samples of African propolis (Congo and Cameroon) and their biological evaluation. Twenty-one secondary metabolites belonging to four different chemical groups were isolated from the 70% ethanolic extracts of propolis and their structures were elucidated on the basis of spectral evidence. Three triterpenes and two diprenyl-flavonoids were identified from Congo propolis, which has been investigated for the first time, while thirteen triterpenes, three diprenyl-flavonoids, two monoterpenic alcohols and one fatty acid ester have been identified from Cameroon propolis samples. To our knowledge, the identified diprenyl-flavonoids, as well as five of the isolated and determined triterpenes, are reported for the first time in propolis. Moreover, the total polyphenol content was estimated in all extracts and the antimicrobial activities of all four extracts were studied against six Gram-positive and -negative bacteria and three pathogenic fungi, showing an interesting antibacterial profile.

  11. Fiber laser-microscope system for femtosecond photodisruption of biological samples.

    Science.gov (United States)

    Yavaş, Seydi; Erdogan, Mutlu; Gürel, Kutan; Ilday, F Ömer; Eldeniz, Y Burak; Tazebay, Uygar H

    2012-03-01

    We report on the development of a ultrafast fiber laser-microscope system for femtosecond photodisruption of biological targets. A mode-locked Yb-fiber laser oscillator generates few-nJ pulses at 32.7 MHz repetition rate, amplified up to ∼125 nJ at 1030 nm. Following dechirping in a grating compressor, ∼240 fs-long pulses are delivered to the sample through a diffraction-limited microscope, which allows real-time imaging and control. The laser can generate arbitrary pulse patterns, formed by two acousto-optic modulators (AOM) controlled by a custom-developed field-programmable gate array (FPGA) controller. This capability opens the route to fine optimization of the ablation processes and management of thermal effects. Sample position, exposure time and imaging are all computerized. The capability of the system to perform femtosecond photodisruption is demonstrated through experiments on tissue and individual cells.

  12. 4D x-ray phase contrast tomography for repeatable motion of biological samples

    Science.gov (United States)

    Hoshino, Masato; Uesugi, Kentaro; Yagi, Naoto

    2016-09-01

    X-ray phase contrast tomography based on a grating interferometer was applied to fast and dynamic measurements of biological samples. To achieve this, the scanning procedure in the tomographic scan was improved. A triangle-shaped voltage signal from a waveform generator to a Piezo stage was used for the fast phase stepping in the grating interferometer. In addition, an optical fiber coupled x-ray scientific CMOS camera was used to achieve fast and highly efficient image acquisitions. These optimizations made it possible to perform an x-ray phase contrast tomographic measurement within an 8 min scan with density resolution of 2.4 mg/cm3. A maximum volume size of 13 × 13 × 6 mm3 was obtained with a single tomographic measurement with a voxel size of 6.5 μm. The scanning procedure using the triangle wave was applied to four-dimensional measurements in which highly sensitive three-dimensional x-ray imaging and a time-resolved dynamic measurement of biological samples were combined. A fresh tendon in the tail of a rat was measured under a uniaxial stretching and releasing condition. To maintain the freshness of the sample during four-dimensional phase contrast tomography, the temperature of the bathing liquid of the sample was kept below 10° using a simple cooling system. The time-resolved deformation of the tendon and each fascicle was measured with a temporal resolution of 5.7 Hz. Evaluations of cross-sectional area size, length of the axis, and mass density in the fascicle during a stretching process provided a basis for quantitative analysis of the deformation of tendon fascicle.

  13. A comparison of quantitative reconstruction techniques for PIXE-tomography analysis applied to biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Beasley, D.G., E-mail: dgbeasley@ctn.ist.utl.pt [IST/C2TN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Alves, L.C. [IST/C2TN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Barberet, Ph.; Bourret, S.; Devès, G.; Gordillo, N.; Michelet, C. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Le Trequesser, Q. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB, UPR9048) CNRS, Université de Bordeaux, 87 avenue du Dr. A. Schweitzer, Pessac F-33608 (France); Marques, A.C. [IST/IPFN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Seznec, H. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Silva, R.C. da [IST/IPFN, Universidade de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal)

    2014-07-15

    The tomographic reconstruction of biological specimens requires robust algorithms, able to deal with low density contrast and low element concentrations. At the IST/ITN microprobe facility new GPU-accelerated reconstruction software, JPIXET, has been developed, which can significantly increase the speed of quantitative reconstruction of Proton Induced X-ray Emission Tomography (PIXE-T) data. It has a user-friendly graphical user interface for pre-processing, data analysis and reconstruction of PIXE-T and Scanning Transmission Ion Microscopy Tomography (STIM-T). The reconstruction of PIXE-T data is performed using either an algorithm based on a GPU-accelerated version of the Maximum Likelihood Expectation Maximisation (MLEM) method or a GPU-accelerated version of the Discrete Image Space Reconstruction Algorithm (DISRA) (Sakellariou (2001) [2]). The original DISRA, its accelerated version, and the MLEM algorithm, were compared for the reconstruction of a biological sample of Caenorhabditis elegans – a small worm. This sample was analysed at the microbeam line of the AIFIRA facility of CENBG, Bordeaux. A qualitative PIXE-T reconstruction was obtained using the CENBG software package TomoRebuild (Habchi et al. (2013) [6]). The effects of pre-processing and experimental conditions on the elemental concentrations are discussed.

  14. Respondent driven sampling for HIV biological and behavioral surveillance in Latin America and the Caribbean.

    Science.gov (United States)

    Montealegre, Jane R; Johnston, Lisa G; Murrill, Christopher; Monterroso, Edgar

    2013-09-01

    Since 2005, respondent driven sampling (RDS) has been widely used for HIV biological and behavioral surveillance surveys (BBSS) in Latin America and the Caribbean (LAC). In this manuscript, we provide a focused review of RDS among hard-to-reach high-risk populations in LAC and describe their principal operational, design, and analytical considerations. We reviewed published and unpublished reports, protocols, and manuscripts for RDS studies conducted in LAC between January 1, 2005 and December 31, 2011. We abstracted key operational information and generated summary statistics across all studies. Between 2005 and 2011, 87 RDS studies were conducted in 15 countries in LAC (68 % in South America, 18 % in Mexico and Central America, and 14 % in the Caribbean). The target populations were primarily men who have sex with men (43 %), sex workers (29 %), and drug users (26 %). Study considerations included establishing clear eligibility criteria, measuring social network sizes, collecting specimens for biological testing, among others. Most of the reviewed studies are the first in their respective countries to collect data on hard-to-reach populations and the first attempt to use a probability-based sampling method. These RDS studies allowed researchers and public health practitioners in LAC to access hard-to-reach HIV high-risk populations and collect valuable data on the prevalence of HIV and other infections, as well as related risk behaviors.

  15. [The biomonitoring of toxic substances in biological samples of general population].

    Science.gov (United States)

    Ibarluzea, Jesús; Aurrekoetxea, Juan José; Porta, Miquel; Sunyer, Jordi; Ballester, Ferran

    2016-11-01

    Many of the world's most developed countries have adopted biomonitoring of toxic substances in order to ascertain their levels in biological samples. These substances get into the body through different environmental exposures. Monitoring toxic substances in biological samples should allow us to ascertain their levels in vulnerable groups, assess their evolution over time, make comparisons with levels observed in other countries, identify groups at risk or with high toxic levels and promote research. The main objective of biomonitoring is to act as a policy design tool to facilitate the implementation of particular measures in various sectors: health, environmental, agricultural and livestock or food industry sectors. In Spain, information on levels of toxic substances of environmental origin is provided by specific studies on health effects from environmental sources, such as the INMA project (INfancia y Medio Ambiente [childhood and environment]). In addition, biomonitoring projects have been implemented in Catalonia and the Canary Islands, together with a national biomonitoring programme in the adult working population. However, further progress is needed to develop a system that covers the general population as well as subgroups at risk, which relies on the collaboration of the involved authorities and the participation of professionals from different sectors and citizen organisations interested in the relationship between health and the environment.

  16. Evaluation of toxic metals in biological samples (scalp hair, blood and urine) of steel mill workers by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Afridi, Hassan I; Kazi, Tasneem G; Jamali, Mohammad K; Kazi, Gul H; Arain, Mohammad B; Jalbani, Nusrat; Shar, Ghulam Q; Sarfaraz, Raja A

    2006-10-01

    The determination of toxic metals in the biological samples of human beings is an important clinical screening procedure. This study aimed to assess the possible influence of environmental exposure on production workers (PW) and quality control workers (QCW) of a steel mill, all male subjects aged 25-55 years. In this investigation, the concentrations of Pb, Cd, Ni and Cr were determined in biological samples (blood, urine and scalp hair samples) from these steel mill workers in relation to controlled unexposed healthy subjects of the same age group. After pre-treatment with nitric acid-hydrogen peroxide, the samples were digested via a microwave oven, and for comparison purposes, the same samples were digested by the conventional wet acid digestion method. The samples digested were subjected to graphite furnace atomic absorption spectrometry (GFAAS). To assess the reliability of these methods, critical factors, such as detection limit(s), calibration range(s), accuracy and precision, were studied. Quality control for these procedures was established with certified sample of human hair, urine and whole blood. The results indicate that the level of lead, cadmium and nickel in scalp hair, blood and urine samples were significantly higher in both groups of exposed workers (QW and PW) than those of the controls. The possible connection of these elements with the etiology of disease is discussed. The results also show the need for immediate improvements in workplace ventilation and industrial hygiene practices.

  17. Label-free three-dimensional reconstruction of biological samples (Conference Presentation)

    Science.gov (United States)

    Aknoun, Sherazade; Bon, Pierre; Savatier, Julien; Monneret, Serge; Wattellier, Benoit F.

    2016-03-01

    We describe the use of spatially incoherent illumination combined with quantitative phase imaging (QPI) [1] to make tridimensional reconstruction of semi-transparent biological samples. Quantitative phase imaging is commonly used with coherent illumination for the relatively simple interpretation of the phase measurement. We propose to use spatially incoherent illumination which is known to increase lateral and axial resolution compared to classical coherent illumination. The goal is to image thick samples with intracellular resolution [2]. The 3D volume is imaged by axially scanning the sample with a quadri-wave lateral shearing interferometer used as a conventional camera while using spatially incoherent white-light illumination (native microscope halogen source) or NIR light. We use a non-modified inverted microscope equipped with a Z-axis piezo stage. A z-stack is recorded by objective translation along the optical axis. The main advantages of this approach are its easy implementation, compared to the other state-of-the-art diffraction tomographic setups, and its speed which makes even label-free 3D living sample imaging possible. A deconvolution algorithm is used to compensate for the loss in contrast due to spatially incoherent illumination. This makes the tomographic volume phase values quantitative. Hence refractive index could be recovered from the optical slices. We will present tomographic reconstruction of cells, thick fixed tissue of few tens of micrometers using white light, and the use of NIR light to reach deeper planes in the tissue.

  18. Label-free three dimensional reconstruction of biological samples (Conference Presentation)

    Science.gov (United States)

    Aknoun, Sherazade; Bon, Pierre; Savatier, Julien; Monneret, Serge; Wattellier, Benoit F.

    2016-03-01

    We describe the use of spatially incoherent illumination combined with quantitative phase imaging (QPI) [1] to make tridimensional reconstruction of semi-transparent biological samples. Quantitative phase imaging is commonly used with coherent illumination for the relatively simple interpretation of the phase measurement. We propose to use spatially incoherent illumination which is known to increase lateral and axial resolution compared to classical coherent illumination. The goal is to image thick samples with intracellular resolution [2]. The 3D volume is imaged by axially scanning the sample with a quadri-wave lateral shearing interferometer used as a conventional camera while using spatially incoherent white-light illumination (native microscope halogen source) or NIR light. We use a non-modified inverted microscope equipped with a Z-axis piezo stage. A z-stack is recorded by objective translation along the optical axis. The main advantages of this approach are its easy implementation, compared to the other state-of-the-art diffraction tomographic setups, and its speed which makes even label-free 3D living sample imaging possible. A deconvolution algorithm is used to compensate for the loss in contrast due to spatially incoherent illumination. This makes the tomographic volume phase values quantitative. Hence refractive index could be recovered from the optical slices. We will present tomographic reconstruction of cells, thick fixed tissue of few tens of micrometers using white light, and the use of NIR light to reach deeper planes in the tissue.

  19. An inexpensive and portable microvolumeter for rapid evaluation of biological samples.

    Science.gov (United States)

    Douglass, John K; Wcislo, William T

    2010-08-01

    We describe an improved microvolumeter (MVM) for rapidly measuring volumes of small biological samples, including live zooplankton, embryos, and small animals and organs. Portability and low cost make this instrument suitable for widespread use, including at remote field sites. Beginning with Archimedes' principle, which states that immersing an arbitrarily shaped sample in a fluid-filled container displaces an equivalent volume, we identified procedures that maximize measurement accuracy and repeatability across a broad range of absolute volumes. Crucial steps include matching the overall configuration to the size of the sample, using reflected light to monitor fluid levels precisely, and accounting for evaporation during measurements. The resulting precision is at least 100 times higher than in previous displacement-based methods. Volumes are obtained much faster than by traditional histological or confocal methods and without shrinkage artifacts due to fixation or dehydration. Calibrations using volume standards confirmed accurate measurements of volumes as small as 0.06 microL. We validated the feasibility of evaluating soft-tissue samples by comparing volumes of freshly dissected ant brains measured with the MVM and by confocal reconstruction.

  20. Preparative divergent flow IEF without carrier ampholytes for separation of complex biological samples.

    Science.gov (United States)

    Stastna, Miroslava; Slais, Karel

    2010-01-01

    Efficient separation method is a crucial part of the process in which components of highly complex biological sample are identified and characterized. Based on the principles of recently newly established electrophoretic method called divergent flow IEF (DF IEF), we have tested the DF IEF instrument which is able to operate without the use of background carrier ampholytes. We have verified that during separation and focusing of sample consisting of high numbers of proteins (yeast lysate and wheat flour extract), the pH gradient of preparative DF IEF can be created by autofocusing of the sample components themselves without any addition of carrier ampholytes. In DF IEF, the proteins are separated, desalted and concentrated in one step. The fractions of yeast lysate sample, collected at the DF IEF output and subjected to gel IEF, contained the zones of proteins gradually covering the pI values from 3.7 to 8.5. In our experimental arrangement, the highest number of proteins has been found in fractions with pI values around 5.3 as detected by polyacrylamide gel IEF with CBB staining. During DF IEF, the selected protein bands have been concentrated up to 16.8-fold.

  1. What is human in humans? Responses from biology, anthropology, and philosophy.

    Science.gov (United States)

    Bibeau, Gilles

    2011-08-01

    Genomics has brought biology, medicine, agriculture, psychology, anthropology, and even philosophy to a new threshold. In this new context, the question about "what is human in humans" may end up being answered by geneticists, specialists of technoscience, and owners of biotech companies. The author defends, in this article, the idea that humanity is at risk in our age of genetic engineering, biotechnologies, and market-geared genetic research; he also argues that the values at the very core of our postgenomic era bring to its peak the science-based ideology that has developed since the time of Galileo, Newton, Descartes, and Harvey; finally, it shows that the bioindustry has invented a new genomythology that goes against the scientific evidence produced by the research in human sciences in which life is interpreted as a language.

  2. Analysis of inorganic elements in biological samples of C57BL/6J mouse strain using INAA

    Energy Technology Data Exchange (ETDEWEB)

    Metairon, Sabrina; Zamboni, Cibele B.; Suzuki, Miriam F.; Kovacs, Luciana, E-mail: metairon@usp.br, E-mail: czamboni@ipen.br, E-mail: mfsuzuki@ipen.br, E-mail: lukovacs@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Bueno Junior, Carlos R., E-mail: carmao11@yahoo.com.br [Universidade de Sao Paulo (IB/USP), Sao Paulo, SP (Brazil). Instituto de Biociencias. Centro de Estudos do Genoma Humano

    2013-07-01

    The research for new medicine, vaccines and other products of interest in health area, for any disease, requires several in vivo tests using animal models on experiments for clinical analysis of actions in organism, focusing on the relation between these and the responses or reactions to their use, allowing or not their use in human being. The present investigation deals with the determination of elements concentration (Ca, Cl, K, Mg and Na) of clinical relevance in kidney and liver of C57BL/6J mice strain using the Instrumental Neutron Activation Analysis technique. Particularly, the C57BL/6J strain is one of the most widely used mice genetically modified for human disease studies. The biological samples were collected from 2 month old adult mice bred in the Biotherium (animal breeding) of UNIFESP (Federal University of Sao Paulo, Brasil) and at Human Genome Research Center (University of Sao Paulo, Brasil) and Biotechnology Center (IPEN, Sao Paulo, Brasil). The measurements were performed in the nuclear reactor IEA-R1 (3.5-4.5MW, pool type) at IPEN. These data will allow researchers to optimize their studies, both in terms of cost and time, by knowing the basal reference values in blood and organs of this strain. Additionally, this analytical procedure meets the needs of the world tendency that emphasizes the requirements to propose alternative methods for clinical research that contribute to animal welfare. (author)

  3. The preparation of albumin as a biological drug from human plasma by fiber filtration

    Directory of Open Access Journals (Sweden)

    Mousavi Hosseini K

    2011-08-01

    Full Text Available "nBackground: In recent years, consumption of whole-blood for the treatment of patients has decreased but use of biological plasma-derived medicines such as albumin, immunoglobulin and coagulation factors have increased instead. Paying attention to albumin molecular structure is important for its isolation from human plasma. Albumin is a single-chain protein consisting of about 585 amino acids and a molecular weight of 66500 Daltons. Albumin is a stable molecule and it is spherical in shape. There are different methods for human albumin preparation. Considering the large consumption of this biological drug in clinical settings, methods with fewer steps in production line are of big advantage in saving time and manufacturing more products."n "nMethods: In this project, we prepared human albumin using hollow fiber cartridges in order to omit the rework on fraction V+VI. Human albumin is usually produced by the application of cold ethanol method, where albumin is obtained from fraction V by doing a rework on fraction V+VI to separate fraction V."n "nResults: In the current work, human albumin was prepared from fraction V+VI by the help of hollow fiber cartridges. With a concentration of 20%, the obtained albumin had 96.5% of monomer and 3.5% of polymer and polymer aggregate."n "nConclusion: Comparing the obtained human albumin with a number of commercial human albumin samples by the use of SDS-page, the results were satisfactory regarding the 3.5 percent polymer and aggregate rate for the prepared albumin.

  4. An enzyme-based DNA preparation method for application to forensic biological samples and degraded stains.

    Science.gov (United States)

    Lounsbury, Jenny A; Coult, Natalie; Miranian, Daniel C; Cronk, Stephen M; Haverstick, Doris M; Kinnon, Paul; Saul, David J; Landers, James P

    2012-09-01

    Extraction of DNA from forensic samples typically uses either an organic extraction protocol or solid phase extraction (SPE) and these methods generally involve numerous sample transfer, wash and centrifugation steps. Although SPE has been successfully adapted to the microdevice, it can be problematic because of lengthy load times and uneven packing of the solid phase. A closed-tube enzyme-based DNA preparation method has recently been developed which uses a neutral proteinase to lyse cells and degrade proteins and nucleases [14]. Following a 20 min incubation of the buccal or whole blood sample with this proteinase, DNA is polymerase chain reaction (PCR)-ready. This paper describes the optimization and quantitation of DNA yield using this method, and application to forensic biological samples, including UV- and heat-degraded whole blood samples on cotton or blue denim substrates. Results demonstrate that DNA yield can be increased from 1.42 (±0.21)ng/μL to 7.78 (±1.40)ng/μL by increasing the quantity of enzyme per reaction by 3-fold. Additionally, there is a linear relationship between the amount of starting cellular material added and the concentration of DNA in the solution, thereby allowing DNA yield estimations to be made. In addition, short tandem repeat (STR) profile results obtained using DNA prepared with the enzyme method were comparable to those obtained with a conventional SPE method, resulting in full STR profiles (16 of 16 loci) from liquid samples (buccal swab eluate and whole blood), dried buccal swabs and bloodstains and partial profiles from UV or heat-degraded bloodstains on cotton or blue denim substrates. Finally, the DNA preparation method is shown to be adaptable to glass or poly(methyl methacrylate) (PMMA) microdevices with little impact on STR peak height but providing a 20-fold reduction in incubation time (as little as 60 s), leading to a ≥1 h reduction in DNA preparation time.

  5. Exploring Earth's Atmospheric Biology using a Platform-Extensible Sampling Payload

    Science.gov (United States)

    Gentry, D.; Rothschild, L.

    2012-12-01

    The interactions between Earth's atmosphere and its biosphere, or aerobiology, remain a significant unknown. What few studies have been done conclusively show that Earth's atmosphere has a rich and dynamic microbial presence[Bowers et al., 2010]; that microbes suspended in air survive over long times (1-2 weeks)[Smith et al., 2010] and travel great distances (>5000 km)[Kellogg and Griffin, 2006]; that some airborne bacteria actively nucleate ice crystals, affecting meteorology[Delort et al., 2010]; and that the presence of microbes in the atmosphere has other planetary-scale effects[Delort et al., 2010]. Basic questions, however, such as the number of microbes present, their activity level and state, the different species present and their variance over time and space, remain largely unquantified. Compounding the significant physical and environmental challenges of reliable aerobiological sampling, collection and analysis of biological samples at altitudes above ~10-20 km has traditionally used ad hoc instrumentation and techniques, yielding primarily qualitative analytical results that lack a common basis for comparison[Bowers et al., 2010]. There is a strong need for broad-basis, repeatable, reliably comparable data about aerobiological basics. We describe here a high-altitude environmental and biological sampling project designed specifically to address these issues. The goal is a robust, reliable, re-usable sampling system, with open reproducibility and adaptability for multiple low-cost flight platforms (including ground-tethered systems, high-altitude balloons, and suborbital sounding rockets); by establishing a common modular payload structure for high-altitude sampling with appeal to a broad user base, we hope to encourage widespread collection of comparable aerobiological data. We are on our third prototype iteration, with demonstrated function of two sample capture modules, a support backbone (tracking, data logging, event response, etc.), a simple ground

  6. Investigation of resins suitable for the preparation of biological sample for 3-D electron microscopy.

    Science.gov (United States)

    Kizilyaprak, Caroline; Longo, Giovanni; Daraspe, Jean; Humbel, Bruno M

    2015-02-01

    In the last two decades, the third-dimension has become a focus of attention in electron microscopy to better understand the interactions within subcellular compartments. Initially, transmission electron tomography (TEM tomography) was introduced to image the cell volume in semi-thin sections (∼ 500 nm). With the introduction of the focused ion beam scanning electron microscope, a new tool, FIB-SEM tomography, became available to image much larger volumes. During TEM tomography and FIB-SEM tomography, the resin section is exposed to a high electron/ion dose such that the stability of the resin embedded biological sample becomes an important issue. The shrinkage of a resin section in each dimension, especially in depth, is a well-known phenomenon. To ensure the dimensional integrity of the final volume of the cell, it is important to assess the properties of the different resins and determine the formulation which has the best stability in the electron/ion beam. Here, eight different resin formulations were examined. The effects of radiation damage were evaluated after different times of TEM irradiation. To get additional information on mass-loss and the physical properties of the resins (stiffness and adhesion), the topography of the irradiated areas was analysed with atomic force microscopy (AFM). Further, the behaviour of the resins was analysed after ion milling of the surface of the sample with different ion currents. In conclusion, two resin formulations, Hard Plus and the mixture of Durcupan/Epon, emerged that were considerably less affected and reasonably stable in the electron/ion beam and thus suitable for the 3-D investigation of biological samples.

  7. Quantitation of enniatins in biological samples of Wistar rats after oral administration by LC-MS/MS.

    Science.gov (United States)

    Escrivá, Laura; Font, Guillermina; Manyes, Lara

    2015-01-01

    The emerging Fusarium mycotoxins enniatins (ENNs) have diverse biological properties, mainly due to their ionophoric activity, and represent a potential risk to human and animal health since they are commonly found in food and feed. In vivo toxicity studies are scarce and limited to the major mycotoxins. Until now, any method for the simultaneous analysis of these compounds in plasma, serum and feces from rat has been reported. A method for the extraction and determination of ENNs A, A1, B and B1 from Wistar rat samples by liquid chromatography tandem mass spectrometry has been developed. The method was successfully validated with satisfactory recoveries (70-106%), good intraday (rat samples that were administered a mixture of ENNs containing 1.19, 2.16, 1.03 and 1.41 mg/kg body weight of ENN A, A1, B and B1, respectively. Blood, urine and feces samples collected every 2 h during the 8-h duration of the experiment were analyzed. The administered dose of the mixture of ENNs did not cause observable adverse effects on the animals. ENNs concentrations detected in serum and urine were below LOQs. The four ENNs were detected in feces reaching the maximum concentration at 6 h after administration.

  8. Serum Albumin Domain Structures in Human Blood Serum by Mass Spectrometry and Computational Biology.

    Science.gov (United States)

    Belsom, Adam; Schneider, Michael; Fischer, Lutz; Brock, Oliver; Rappsilber, Juri

    2016-03-01

    Chemical cross-linking combined with mass spectrometry has proven useful for studying protein-protein interactions and protein structure, however the low density of cross-link data has so far precluded its use in determining structures de novo. Cross-linking density has been typically limited by the chemical selectivity of the standard cross-linking reagents that are commonly used for protein cross-linking. We have implemented the use of a heterobifunctional cross-linking reagent, sulfosuccinimidyl 4,4'-azipentanoate (sulfo-SDA), combining a traditional sulfo-N-hydroxysuccinimide (sulfo-NHS) ester and a UV photoactivatable diazirine group. This diazirine yields a highly reactive and promiscuous carbene species, the net result being a greatly increased number of cross-links compared with homobifunctional, NHS-based cross-linkers. We present a novel methodology that combines the use of this high density photo-cross-linking data with conformational space search to investigate the structure of human serum albumin domains, from purified samples, and in its native environment, human blood serum. Our approach is able to determine human serum albumin domain structures with good accuracy: root-mean-square deviation to crystal structure are 2.8/5.6/2.9 Å (purified samples) and 4.5/5.9/4.8Å (serum samples) for domains A/B/C for the first selected structure; 2.5/4.9/2.9 Å (purified samples) and 3.5/5.2/3.8 Å (serum samples) for the best out of top five selected structures. Our proof-of-concept study on human serum albumin demonstrates initial potential of our approach for determining the structures of more proteins in the complex biological contexts in which they function and which they may require for correct folding. Data are available via ProteomeXchange with identifier PXD001692.

  9. Estimation of the fraction of biologically active methyl tert-butyl ether degraders in a heterogeneous biomass sample

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2008-01-01

    The fraction of biologically active methyl tert-butyl ether degraders in reactors is just as important for prediction of removal rates as knowledge of the kinetic parameters. The fraction of biologically active methyl tert-butyl ether degraders in a heterogeneous biomass sample, taken from a packed...

  10. The Constitutive Content of the Crime of Refusal or Evasion from Collecting Biological Samples in the Romanian Criminal Law

    National Research Council Canada - National Science Library

    Minodora-Ioana BĂLAN-RUSU

    2015-01-01

    In the paper we have examined the constitutive content of the offense of refusal or evasion from collecting biological samples, with elements of similarity and differences between the current and the old law...

  11. The DNA sequence and biology of human chromosome 19.

    Science.gov (United States)

    Grimwood, Jane; Gordon, Laurie A; Olsen, Anne; Terry, Astrid; Schmutz, Jeremy; Lamerdin, Jane; Hellsten, Uffe; Goodstein, David; Couronne, Olivier; Tran-Gyamfi, Mary; Aerts, Andrea; Altherr, Michael; Ashworth, Linda; Bajorek, Eva; Black, Stacey; Branscomb, Elbert; Caenepeel, Sean; Carrano, Anthony; Caoile, Chenier; Chan, Yee Man; Christensen, Mari; Cleland, Catherine A; Copeland, Alex; Dalin, Eileen; Dehal, Paramvir; Denys, Mirian; Detter, John C; Escobar, Julio; Flowers, Dave; Fotopulos, Dea; Garcia, Carmen; Georgescu, Anca M; Glavina, Tijana; Gomez, Maria; Gonzales, Eidelyn; Groza, Matthew; Hammon, Nancy; Hawkins, Trevor; Haydu, Lauren; Ho, Isaac; Huang, Wayne; Israni, Sanjay; Jett, Jamie; Kadner, Kristen; Kimball, Heather; Kobayashi, Arthur; Larionov, Vladimer; Leem, Sun-Hee; Lopez, Frederick; Lou, Yunian; Lowry, Steve; Malfatti, Stephanie; Martinez, Diego; McCready, Paula; Medina, Catherine; Morgan, Jenna; Nelson, Kathryn; Nolan, Matt; Ovcharenko, Ivan; Pitluck, Sam; Pollard, Martin; Popkie, Anthony P; Predki, Paul; Quan, Glenda; Ramirez, Lucia; Rash, Sam; Retterer, James; Rodriguez, Alex; Rogers, Stephanine; Salamov, Asaf; Salazar, Angelica; She, Xinwei; Smith, Doug; Slezak, Tom; Solovyev, Victor; Thayer, Nina; Tice, Hope; Tsai, Ming; Ustaszewska, Anna; Vo, Nu; Wagner, Mark; Wheeler, Jeremy; Wu, Kevin; Xie, Gary; Yang, Joan; Dubchak, Inna; Furey, Terrence S; DeJong, Pieter; Dickson, Mark; Gordon, David; Eichler, Evan E; Pennacchio, Len A; Richardson, Paul; Stubbs, Lisa; Rokhsar, Daniel S; Myers, Richard M; Rubin, Edward M; Lucas, Susan M

    2004-04-01

    Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G + C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.

  12. Can Chimpanzee Biology Highlight Human Origin and Evolution?

    Directory of Open Access Journals (Sweden)

    Itai Roffman

    2010-07-01

    Full Text Available The closest living relatives of humans are their chimpanzee/bonobo (Pan sister species, members of the same subfamily “Homininae”. This classification is supported by over 50 years of research in the fields of chimpanzee cultural diversity, language competency, genomics, anatomy, high cognition, psychology, society, self-consciousness and relation to others, tool use/production, as well as Homo level emotions, symbolic competency, memory recollection, complex multifaceted problem-solving capabilities, and interspecies communication. Language competence and symbolism can be continuously bridged from chimpanzee to man. Emotions, intercommunity aggression, body language, gestures, facial expressions, and vocalization of intonations seem to parallel between the sister taxa Homo and Pan. The shared suite of traits between Pan and Homo genus demonstrated in this article integrates old and new information on human–chimpanzee evolution, bilateral informational and cross-cultural exchange, promoting the urgent need for Pan cultures in the wild to be protected, as they are part of the cultural heritage of mankind. Also, we suggest that bonobos, Pan paniscus, based on shared traits with Australopithecus, need to be included in Australopithecine’s subgenus, and may even represent living-fossil Australopithecines. Unfolding bonobo and chimpanzee biology highlights our common genetic and cultural evolutionary origins.

  13. The DNA sequence and biology of human chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Grimwood, J; Gordon, L A; Olsen, A; Terry, A; Schmutz, J; Lamerdin, J; Hellsten, U; Goodstein, D; Couronne, O; Tran-Gyamfi, M

    2004-04-06

    Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high GC content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in Mendelian disorders, including familial hypercholesterolemia and insulin-resistant diabetes. Nearly one quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.

  14. The DNA sequence and biology of human chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Grimwood, Jane; Gordon, Laurie A.; Olsen, Anne; Terry, Astrid; Schmutz, Jeremy; Lamerdin, Jane; Hellsten, Uffe; Goodstein, David; Couronne, Olivier; Tran-Gyamfi, Mary; Aerts, Andrea; Altherr, Michael; Ashworth, Linda; Bajorek, Eva; Black, Stacey; Branscomb, Elbert; Caenepeel, Sean; Carrano, Anthony; Caoile, Chenier; Chan, Yee Man; Christensen, Mari; Cleland, Catherine A.; Copeland, Alex; Dalin, Eileen; Dehal, Paramvir; Denys, Mirian; Detter, John C.; Escobar, Julio; Flowers, Dave; Fotopulos, Dea; Garcia, Carmen; Georgescu, Anca M.; Glavina, Tijana; Gomez, Maria; Gonzales, Eldelyn; Groza, Matthew; Hammon, Nancy; Hawkins, Trevor; Haydu, Lauren; Ho, Issac; Huang, Wayne; Israni, Sanjay; Jett, Jamie; Kadner, Kristen; Kimball, Heather; Kobayashi, Arthur; Larionov, Vladimer; Leem, Sun-Hee; Lopez, Frederick; Lou, Yunian; Lowry, Steve; Malfatti, Stephanie; Martinez, Diego; McCready, Paula; Medina, Catherine; Morgan, Jenna; Nelson, Kathryn; Nolan, Matt; Ovcharenko, Ivan; Pitluck, Sam; Pollard, Martin; Popkie, Anthony P.; Predki, Paul; Quan, Glenda; Ramirez, Lucia; Rash, Sam; Retterer, James; Rodriguez, Alex; Rogers, Stephanine; Salamov, Asaf; Salazar, Angelica; She, Xinwei; Smith, Doug; Slezak, Tom; Solovyev, Victor; Thayer, Nina; Tice, Hope; Tsai, Ming; Ustaszewska, Anna; Vo, Nu; Wagner, Mark; Wheeler, Jeremy; Wu, Kevin; Xie, Gary; Yang, Joan; Dubchak, Inna; Furey, Terrence S.; DeJong, Pieter; Dickson, Mark; Gordon, David; Eichler, Evan E.; Pennacchio, Len A.; Richardson, Paul; Stubbs, Lisa; Rokhsar, Daniel S.; Myers, Richard M.; Rubin, Edward M.; Lucas, Susan M.

    2003-09-15

    Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G1C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9 percent of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25 percent of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, a nd segments of coding and non-coding conservation with the distant fish species Takifugu.

  15. Molecular dynamics simulations of biological membranes and membrane proteins using enhanced conformational sampling algorithms.

    Science.gov (United States)

    Mori, Takaharu; Miyashita, Naoyuki; Im, Wonpil; Feig, Michael; Sugita, Yuji

    2016-07-01

    This paper reviews various enhanced conformational sampling methods and explicit/implicit solvent/membrane models, as well as their recent applications to the exploration of the structure and dynamics of membranes and membrane proteins. Molecular dynamics simulations have become an essential tool to investigate biological problems, and their success relies on proper molecular models together with efficient conformational sampling methods. The implicit representation of solvent/membrane environments is reasonable approximation to the explicit all-atom models, considering the balance between computational cost and simulation accuracy. Implicit models can be easily combined with replica-exchange molecular dynamics methods to explore a wider conformational space of a protein. Other molecular models and enhanced conformational sampling methods are also briefly discussed. As application examples, we introduce recent simulation studies of glycophorin A, phospholamban, amyloid precursor protein, and mixed lipid bilayers and discuss the accuracy and efficiency of each simulation model and method. This article is part of a Special Issue entitled: Membrane Proteins edited by J.C. Gumbart and Sergei Noskov.

  16. Troubleshooting digital macro photography for image acquisition and the analysis of biological samples.

    Science.gov (United States)

    Liepinsh, Edgars; Kuka, Janis; Dambrova, Maija

    2013-01-01

    For years, image acquisition and analysis have been an important part of life science experiments to ensure the adequate and reliable presentation of research results. Since the development of digital photography and digital planimetric methods for image analysis approximately 20 years ago, new equipment and technologies have emerged, which have increased the quality of image acquisition and analysis. Different techniques are available to measure the size of stained tissue samples in experimental animal models of disease; however, the most accurate method is digital macro photography with software that is based on planimetric analysis. In this study, we described the methodology for the preparation of infarcted rat heart and brain tissue samples before image acquisition, digital macro photography techniques and planimetric image analysis. These methods are useful in the macro photography of biological samples and subsequent image analysis. In addition, the techniques that are described in this study include the automated analysis of digital photographs to minimize user input and exclude the risk of researcher-generated errors or bias during image analysis.

  17. Mercury speciation and total trace element determination of low-biomass biological samples.

    Science.gov (United States)

    Taylor, Vivien F; Jackson, Brian P; Chen, Celia Y

    2008-12-01

    Current approaches to mercury speciation and total trace element analysis require separate extraction/digestions of the sample. Ecologically important aquatic organisms--notably primary consumers such as zooplankton, polychaetes and amphipods--usually yield very low biomass for analysis, even with significant compositing of multiple organisms. Individual organisms in the lower aquatic food chains (mussels, snails, oysters, silversides, killifish) can also have very low sample mass, and analysis of whole single organisms is important to metal uptake studies. A method for the determination of both methyl Hg and total heavy metal concentrations (Zn, As, Se, Cd, Hg, Pb) in a single, low-mass sample of aquatic organisms was developed. Samples (2 to 50 mg) were spiked with enriched with (201)MeHg and (199)Hg, then leached in 4 M HNO(3) at 55 degrees C for extraction of MeHg. After 16 h, an aliquot (0.05 mL) was removed to determine mercury species (methyl and inorganic Hg) by isotope dilution gas chromatography inductively coupled plasma mass spectrometry (ICP-MS). The leachate was then acidified to 9 M HNO(3) and digested in a microwave at 150 degrees C for 10 min, and total metal concentrations were determined by collision cell ICP-MS. The method was validated by analyzing five biological certified reference materials. Average percent recoveries for Zn, As, Se, Cd, MeHg, Hg(total) and Pb were 99.9%, 103.5%, 100.4%, 103.3%, 101%, 97.7%, and 97.1%, respectively. The correlation between the sum of MeHg and inorganic Hg from the speciation analysis and total Hg by conventional digestion of the sample was determined for a large sample set of aquatic invertebrates (n = 285). Excellent agreement between the two measured values was achieved. This method is advantageous in situations where sample size is limited, and where correlations between Hg species and other metals are required in the same sample. The method also provides further validation of speciation data, by

  18. Optimization of a Pre-MEKC Separation SPE Procedure for Steroid Molecules in Human Urine Samples

    Directory of Open Access Journals (Sweden)

    Ilona Olędzka

    2013-11-01

    Full Text Available Many steroid hormones can be considered as potential biomarkers and their determination in body fluids can create opportunities for the rapid diagnosis of many diseases and disorders of the human body. Most existing methods for the determination of steroids are usually time- and labor-consuming and quite costly. Therefore, the aim of analytical laboratories is to develop a new, relatively low-cost and rapid implementation methodology for their determination in biological samples. Due to the fact that there is little literature data on concentrations of steroid hormones in urine samples, we have made attempts at the electrophoretic determination of these compounds. For this purpose, an extraction procedure for the optimized separation and simultaneous determination of seven steroid hormones in urine samples has been investigated. The isolation of analytes from biological samples was performed by liquid-liquid extraction (LLE with dichloromethane and compared to solid phase extraction (SPE with C18 and hydrophilic-lipophilic balance (HLB columns. To separate all the analytes a micellar electrokinetic capillary chromatography (MECK technique was employed. For full separation of all the analytes a running buffer (pH 9.2, composed of 10 mM sodium tetraborate decahydrate (borax, 50 mM sodium dodecyl sulfate (SDS, and 10% methanol was selected. The methodology developed in this work for the determination of steroid hormones meets all the requirements of analytical methods. The applicability of the method has been confirmed for the analysis of urine samples collected from volunteers—both men and women (students, amateur bodybuilders, using and not applying steroid doping. The data obtained during this work can be successfully used for further research on the determination of steroid hormones in urine samples.

  19. Electrochemical Analysis of Antichemotherapeutic Drug Zanosar in Pharmaceutical and Biological Samples by Differential Pulse Polarography

    Directory of Open Access Journals (Sweden)

    Chennupalle Nageswara Reddy

    2013-01-01

    Full Text Available The electrochemical reduction of zanosar was investigated systematically by direct current polarography, cyclic voltammetry, and differential pulse polarography (DPP. A simple DPP technique was proposed for the direct quantitative determination of anticancer drug zanosar in pharmaceutical formulation and spiked human urine samples for the first time. The reduction potential was −0.28 V versus Ag/AgCl with a hanging mercury drop electrode in Britton-Robinson buffer as supporting electrolyte. The dependence of the intensities of currents and potentials on pH, concentration, scan rate, deposition time, and nature of the supporting electrolyte was investigated. The calibration curve was found to be linear with the following equation: y=0.4041x+0.012, with a correlation coefficient of 0.992 (R2 over a concentration range from 1.0×10-7 M to 1.0×10-3 M. In the present investigation, the achieved limit of detection (LOD and limit of quantization (LQD were 7.42×10-8 M and 2.47×10-8 M; respectively. Excipients did not interfere with the determination of zanosar in pharmaceutical formulation and spiked urine samples. Precision and accuracy of the developed method were checked by recovery studies in pharmaceutical formulation and spiked human urine samples.

  20. Evaluation of cadmium, lead, nickel and zinc status in biological samples of smokers and nonsmokers hypertensive patients

    OpenAIRE

    H. I. Afridi; Kazi, T G; Kazi, N G; Jamali, M K; Arain, M B; Sirajuddin,; Baig, J. A.; Kandhro, G A; Wadhwa, S K; Shah, A Q

    2009-01-01

    The objective of this study was to evaluate the association between trace and toxic elements zinc (Zn), cadmium (Cd), nickel (Ni) and lead (Pb) in biological samples (scalp hair, blood and urine) of smoker and nonsmoker hypertensive patients (n=457), residents of Hyderabad, Pakistan. For the purpose of comparison, the biological samples of age-matched healthy controls were selected as referents. The concentrations of trace and toxic elements were measured by atomic absorption spectrophotomete...

  1. Monitoring prion protein expression in complex biological samples by SERS for diagnostic applications

    Energy Technology Data Exchange (ETDEWEB)

    Manno, D; Filippo, E; Fiore, R; Serra, A [Dipartimento di Scienza dei Materiali, Universita del Salento, Lecce (Italy); Urso, E; Rizzello, A; Maffia, M [Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Universita del Salento, Lecce (Italy)

    2010-04-23

    Surface-enhanced Raman spectroscopy (SERS) allows a new insight into the analysis of cell physiology. In this work, the difficulty of producing suitable substrates that, besides permitting the amplification of the Raman signal, do not interact with the biological material causing alteration, has been overcome by a combined method of hydrothermal green synthesis and thermal annealing. The SERS analysis of the cell membrane has been performed with special attention to the cellular prion protein PrP{sup C}. In addition, SERS has also been used to reveal the prion protein-Cu(II) interaction in four different cell models (B104, SH-SY5Y, GN11, HeLa), expressing PrP{sup C} at different levels. A significant implication of the current work consists of the intriguing possibility of revealing and quantifying prion protein expression in complex biological samples by a cheap SERS-based method, replacing the expensive and time-consuming immuno-assay systems commonly employed.

  2. Differential scanning calorimetry as a complementary diagnostic tool for the evaluation of biological samples.

    Science.gov (United States)

    Garbett, Nichola C; Brock, Guy N

    2016-05-01

    Differential scanning calorimetry (DSC) is a tool for measuring the thermal stability profiles of complex molecular interactions in biological fluids. DSC profiles (thermograms) of biofluids provide specific signatures which are being utilized as a new diagnostic approach for characterizing disease but the development of these approaches is still in its infancy. This article evaluates several approaches for the analysis of thermograms which could increase the utility of DSC for clinical application. Thermograms were analyzed using localized thermogram features and principal components (PCs). The performance of these methods was evaluated alongside six models for the classification of a data set comprised of 300 systemic lupus erythematosus (SLE) patients and 300 control subjects obtained from the Lupus Family Registry and Repository (LFRR). Classification performance was substantially higher using the penalized algorithms relative to localized features/PCs alone. The models were grouped into two sets, the first having smoother solution vectors but lower classification accuracies than the second with seemingly noisier solution vectors. Coupling thermogram technology with modern classification algorithms provides a powerful diagnostic approach for analysis of biological samples. The solution vectors from the models may reflect important information from the thermogram profiles for discriminating between clinical groups. DSC thermograms show sensitivity to changes in the bulk plasma proteome that correlate with clinical status. To move this technology towards clinical application the development of new approaches is needed to extract discriminatory parameters from DSC profiles for the comparison and diagnostic classification of patients. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Trace Level Arsenic Quantification through Cloud Point Extraction: Application to Biological and Environmental Samples

    Directory of Open Access Journals (Sweden)

    Kempahanumakkagari Suresh Kumar

    2012-01-01

    Full Text Available A sensitive solvent-free extraction protocol for the quantification of arsenic at trace level has been described. It is based on the reaction of arsenic (V with molybdate in acidic medium in presence of antimony (III and ascorbic acid as a reducing agent to form a blue-colored arsenomolybdenum blue complex. The complex has been extracted into surfactant phase using Triton X-114, and its absorbance was measured at 690 nm. The detection limit, working range, and the relative standard deviation were found to be 1 ng mL−1, 10–200 ng mL−1, and 1.2%, respectively. The effect of common ions was studied, and the method has been applied to determine trace levels of As(III and As(V from a variety of samples like environmental, biological, and commercially procured chemicals.

  4. Determination of Sodium Cromoglycate by a New Kinetic Spectrophotometric Method in Biological Samples

    Directory of Open Access Journals (Sweden)

    Mohsen Keyvanfard

    2013-01-01

    Full Text Available A new kinetic spectrophotometric method is described for the determination of ultratrace amounts of sodium cromoglycate (SCG. The method based on catalytic action of SCG on the oxidation of amaranth with periodate in acidic and micellar medium. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of the amaranth at 518 nm, for the first 4 min from initiation of the reaction. Calibration curve was linear in the range of 4.0−36.0 ng mL−1 SCG. The limit of detection is 2.7 ng mL−1 SCG. The relative standard deviation (RSD for ten replicate analyses of 12, 20, and 28 ng mL−1 SCG was 0.40%, 0.32%, and 0.53%, respectively. The proposed method was used for the determination of SCG in biological samples.

  5. Selective spectrofluorimetric determination of zinc in biological samples by Flow Injection Analysis (FIA)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, P.; Perez Conde, C.; Gutierrez, A.; Camara, C. (Universidad Complutense, Madrid (Spain). Dept. de Quimica Analitica)

    1992-03-01

    The automatization of a spectrofluorimetric method for the determination of zinc at trace level is described. It is based on the formation of the fluorescent complex Zn(II)-5,7-dibromo-8-quinolinol (Zn(II)-DBQ) followed by extraction into diethylether using flow injection analysis. The optimum fluorescent emission is reached in hexamethylenetetramine (H{sub 2}MTA{sup +}/HMTA) buffer pH 6.0. A membrane phase separator was used. The calibration graph is linear up to 1.5 {mu}g/ml of Zn(II). The proposed method (detection limit 3 ng/ml) is very selective and has been successfully applied to determine Zn(II) in biological samples, tap waters and various food items. (orig.).

  6. Determination of gadolinium-based MRI contrast agents in biological and environmental samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Telgmann, Lena [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany); Sperling, Michael [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany); European Virtual Institute for Speciation Analysis (EVISA), Münster (Germany); Karst, Uwe, E-mail: uk@uni-muenster.de [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany)

    2013-02-18

    Highlights: ► All major methods for the analysis of Gd-based MRI contrast agents are discussed. ► Biological and environmental samples are covered. ► Pharmacokinetics and species transformation can be investigated. ► The figures of merit as limit of detection and analysis time are described. -- Abstract: The development of analytical methods and strategies to determine gadolinium and its complexes in biological and environmental matrices is evaluated in this review. Gadolinium (Gd) chelates are employed as contrast agents for magnetic resonance imaging (MRI) since the 1980s. In general they were considered as safe and well-tolerated, when in 2006, the disease nephrogenic systemic fibrosis (NSF) was connected to the administration of MRI contrast agents based on Gd. Pathogenesis and etiology of NSF are yet unclear and called for the development of several analytical methods to obtain elucidation in this field. Determination of Gd complex stability in vitro and in vivo, as well as the quantification of Gd in body fluids like blood and urine was carried out. Separation of the Gd chelates was achieved with high performance liquid chromatography (HPLC) and capillary electrophoresis (CE). For detection, various methods were employed, including UV–vis absorbance and fluorescence spectroscopy, electrospray ionization mass spectrometry (ESI-MS) and inductively coupled plasma mass spectrometry (ICP-MS). A second challenge for analysts was the discovery of high concentrations of anthropogenic Gd in surface waters draining populated areas. The source could soon be determined to be the increasing administration of Gd complexes during MRI examinations. Identification and quantification of the contrast agents was carried out in various surface and groundwater samples to determine the behavior and fate of the Gd chelates in the environment. The improvement of limits of detection (LOD) and limits of quantification (LOQ) was and still is the goal of past and ongoing

  7. Human development I: twenty fundamental problems of biology, medicine, and neuro-psychology related to biological information.

    Science.gov (United States)

    Hermansen, Tyge Dahl; Ventegodt, Søren; Rald, Erik; Clausen, Birgitte; Nielsen, Maj Lyck; Merrick, Joav

    2006-07-06

    In a new series of papers, we address a number of unsolved problems in biology today. First of all, the unsolved enigma concerning how the differentiation from a single zygote to an adult individual happens has been object for severe research for decades. By uncovering a new holistic biological paradigm that introduces an energetic-informational interpretation of reality as a new way to experience biology, these papers will try to solve the problems connected with the events of biological ontogenesis involving a fractal hierarchy, from a single cell to the function of the human brain. The problems discussed are interpreted within the frames of a universe of roomy fractal structures containing energetic patterns that are able to deliver biological information. We think biological organization is guided by energetic changes on the level of quantum mechanics, interacting with the intention that again guides the energetic conformation of the fractal structures to gain disorders or healthiness. Furthermore, we introduce two new concepts: "metamorphous top down" evolution and "adult human metamorphosis". The first is a new evolutionary theory involving metamorphosis as a main concept of evolution. The last is tightly linked to the evolutionary principle and explains how human self-recovery is governed. Other subjects of special interest that we shall look deeper into are the immunological self-nonself discrimination, the structure and function of the human brain, the etiology and salutogenesis of mental and somatic diseases, and the structure of the consciousness of a human being. We shall criticize Szentagothai's model for the modulated structure of the human cerebral cortex and Jerne's theory of the immunological regulatory anti-idiotypic network.

  8. Human development I: Twenty Fundamental Problems of Biology, Medicine, and Neuro-Psychology Related to Biological Information

    Directory of Open Access Journals (Sweden)

    Tyge Dahl Hermansen

    2006-01-01

    Full Text Available In a new series of papers, we address a number of unsolved problems in biology today. First of all, the unsolved enigma concerning how the differentiation from a single zygote to an adult individual happens has been object for severe research for decades. By uncovering a new holistic biological paradigm that introduces an energetic-informational interpretation of reality as a new way to experience biology, these papers will try to solve the problems connected with the events of biological ontogenesis involving a fractal hierarchy, from a single cell to the function of the human brain. The problems discussed are interpreted within the frames of a universe of roomy fractal structures containing energetic patterns that are able to deliver biological information. We think biological organization is guided by energetic changes on the level of quantum mechanics, interacting with the intention that again guides the energetic conformation of the fractal structures to gain disorders or healthiness. Furthermore, we introduce two new concepts: “metamorphous top down” evolution and “adult human metamorphosis”. The first is a new evolutionary theory involving metamorphosis as a main concept of evolution. The last is tightly linked to the evolutionary principle and explains how human self-recovery is governed. Other subjects of special interest that we shall look deeper into are the immunological self-nonself discrimination, the structure and function of the human brain, the etiology and salutogenesis of mental and somatic diseases, and the structure of the consciousness of a human being. We shall criticize Szentagothai’s model for the modulated structure of the human cerebral cortex and Jerne’s theory of the immunological regulatory anti-idiotypic network.

  9. Phase microscopy of technical and biological samples through random phase modulation with a difuser

    DEFF Research Database (Denmark)

    Almoro, Percival; Pedrini, Giancarlo; Gundu, Phanindra Narayan

    2010-01-01

    A technique for phase microscopy using a phase diffuser and a reconstruction algorithm is proposed. A magnified specimen wavefront is projected on the diffuser plane that modulates the wavefront into a speckle field. The speckle patterns at axially displaced planes are sampled and used...... in an iterative phase retrieval algorithm based on a wave-propagation equation. The technique offers a whole-field and high-resolution wavefront reconstruction of unstained microstructures. Phase maps of photoresist targets and human cheek cells are obtained to demonstrate the effectiveness of our method. (C......) 2010 Optical Society of America...

  10. Determination of trace lead in biological and water samples with dispersive liquid-liquid microextraction preconcentration.

    Science.gov (United States)

    Liang, Pei; Sang, Hongbo

    2008-09-01

    A new method for the determination of trace lead was developed by dispersive liquid-liquid microextraction preconcentration and graphite furnace atomic absorption spectrometry. In the proposed approach, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was used as a chelating agent, and carbon tetrachloride and ethanol were selected as extraction and dispersive solvents. Some factors influencing the extraction efficiency of lead and its subsequent determination, including extraction and dispersive solvent type and volume, pH of sample solution, concentration of the chelating agent, and extraction time, were studied and optimized. Under the optimum conditions, the enrichment factor of this method for lead was reached at 78. The detection limit for lead was 39 ng L(-1) (3 sigma), and the relative standard deviation (RSD) was 3.2% (n=7, c=10 ng mL(-1)). The method was successfully applied to the determination of trace amounts of lead in human urine and water samples.

  11. Comparative quantification of Campylobacter jejuni from environmental samples using traditional and molecular biological techniques.

    Science.gov (United States)

    Rothrock, Michael J; Cook, Kimberly L; Bolster, Carl H

    2009-06-01

    Campylobacter jejuni is one of the most common causes of gastroenteritis in the world. Given the potential risks to human, animal, and environmental health, the development and optimization of methods to quantify this important pathogen in environmental samples is essential. Two of the most commonly used methods for quantifying C. jejuni are selective plate counting and quantitative real-time PCR (qPCR). Unfortunately, little comparative research has been performed to evaluate the accuracy of these methods for quantification of C. jejuni in aqueous and solid matricies. In this study, the limit of detection and the level of resolution obtained using these 2 methods was evaluated for C. jejuni and compared with that of the common indicator organism Escherichia coli. The use of selective plate count media for quantification of C. jejuni resulted in a 0.7-1.2 log underestimation of cell concentrations, compared with qPCR in both water and column leachate samples, whereas E. coli concentrations were found to be similar with either technique. For C. jejuni, only the qPCR assay accurately measured 2-fold changes in cell concentrations in water samples, whereas concentrations of E. coli were accurately measured regardless of method. Based on these data, qPCR assays were found to be more accurate than selective plate counts for quantification of C. jejuni from environmental samples.

  12. A simple sample preparation method for measuring amoxicillin in human plasma by hollow fiber centrifugal ultrafiltration.

    Science.gov (United States)

    Dong, Wei-Chong; Hou, Zi-Li; Jiang, Xin-Hui; Jiang, Ye

    2013-02-01

    A simple sample preparation method has been developed for the determination of amoxicillin in human plasma by hollow fiber centrifugal ultrafiltration (HF-CF-UF). A 400-μL plasma sample was placed directly into the HF-CF-UF device, which consisited of a slim glass tube and a U-shaped hollow fiber. After centrifugation at 1.25 × 10(3) g for 10 min, the filtrate was withdrawn from the hollow fiber and 20 µL was directly injected into the high-performance liquid chromatography (HPLC) for analysis. The calibration curve was linear over the range of 0.1-20 µg/mL (r = 0.9996) and the limit of detection was as low as 0.025 µg/mL. The average recovery and absolute recovery were 99.9% and 84.5%, respectively. Both the intra-day and inter-day precisions (relative standard deviation) were less than 3.1% for three concentrations (0.25, 2.5 and 10 µg/mL). The sample preparation process was simplified. Only after a single centrifugal ultrafiltration can the filtrate be injected directly into HPLC. The present method is simple, sensitive and accurate. It could be effective for the analysis of biological samples with high protein contents, especially for the biopharmaceutical analysis of drugs that use traditional isolation techniques for sample preparation such as the protein precipitation method.

  13. Small Sample Kernel Association Tests for Human Genetic and Microbiome Association Studies.

    Science.gov (United States)

    Chen, Jun; Chen, Wenan; Zhao, Ni; Wu, Michael C; Schaid, Daniel J

    2016-01-01

    Kernel machine based association tests (KAT) have been increasingly used in testing the association between an outcome and a set of biological measurements due to its power to combine multiple weak signals of complex relationship with the outcome through the specification of a relevant kernel. Human genetic and microbiome association studies are two important applications of KAT. However, the classic KAT framework relies on large sample theory, and conservativeness has been observed for small sample studies, especially for microbiome association studies. The common approach for addressing the small sample problem relies on computationally intensive resampling methods. Here, we derive an exact test for KAT with continuous traits, which resolve the small sample conservatism of KAT without the need for resampling. The exact test has significantly improved power to detect association for microbiome studies. For binary traits, we propose a similar approximate test, and we show that the approximate test is very powerful for a wide range of kernels including common variant- and microbiome-based kernels, and the approximate test controls the type I error well for these kernels. In contrast, the sequence kernel association tests have slightly inflated genomic inflation factors after small sample adjustment. Extensive simulations and application to a real microbiome association study are used to demonstrate the utility of our method. © 2015 WILEY PERIODICALS, INC.

  14. Synchrotron-based X-ray fluorescence, imaging and elemental mapping from biological samples

    Indian Academy of Sciences (India)

    D V Rao; M Swapna; R Cesareo; A Brunetti; T Akatsuka; T Yuasa; T Takeda; G E Gigante

    2011-02-01

    The present study utilized the new hard X-ray microspectroscopy beamline facility, X27A, available at NSLS, BNL, USA, for elemental mapping. This facility provided the primary beam in a small spot of the order of ∼ 10 m, for focussing. With this spatial resolution and high flux throughput, the synchrotron-based X-ray fluorescent intensities for Mn, Fe, Zn, Cr, Ti and Cu were measured using a liquid-nitrogen-cooled 13-element energy-dispersive high-purity germanium detector. The sample is scanned in a `step-and-repeat’ mode for fast elemental mapping measurements and generated elemental maps at 8, 10 and 12 keV, from a small animal shell (snail). The accumulated trace elements, from these biological samples, in small areas have been identified. Analysis of the small areas will be better suited to establish the physiology of metals in specific structures like small animal shell and the distribution of other elements.

  15. A new HPLC method for the direct analysis of triglycerides of dicarboxylic acids in biological samples.

    Science.gov (United States)

    Capristo, E; Mingrone, G; De Gaetano, A; Addolorato, G; Greco, A V; Gasbarrini, G

    1999-11-01

    Dicarboxylic acids (DA) are alternate lipid substrates recently proposed in parenteral nutrition. Two new derivatives of DA, a triglyceride of sebacic (TGC10) and one of dodecanedioic (TGC12) acid have been synthesised in order to reduce the amount of sodium given with the unesterified forms. The present paper describes a rapid and direct high-performance liquid chromatographic method (HPLC) for the analysis of these substances in both plasma and urine. Thirty-six male Wistar rats were rapidly injected with 64 mg of TGC10 or 53 mg of TGC12. The triglycerides and their products of hydrolysis were measured in plasma samples taken at different times. For the dose of 500 ng the intra-assay variations ranged from 6. 80+/-0.35% for TGC10 to 18.6+/-3.20% for TGC12 and the inter-assay variations were from 4.44+/-2.21% for TGC10 to 15.0+/-6.72% for TGC12. The detection limit for both triglycerides was 5 ng. This rapid and direct HPLC method could have practical implications in monitoring the concentration of both triglycerides and free forms of DA in biological samples of patients who might benefit from the administration of these substances during parenteral nutrition regimens.

  16. Assessment of DDT levels in selected environmental media and biological samples from Mexico and Central America.

    Science.gov (United States)

    Pérez-Maldonado, Iván N; Trejo, Antonio; Ruepert, Clemens; Jovel, Reyna del Carmen; Méndez, Mónica Patricia; Ferrari, Mirtha; Saballos-Sobalvarro, Emilio; Alexander, Carlos; Yáñez-Estrada, Leticia; Lopez, Dania; Henao, Samuel; Pinto, Emilio R; Díaz-Barriga, Fernando

    2010-03-01

    Taking into account the environmental persistence and the toxicity of DDT, the Pan American Health Organization (PAHO) organized a surveillance program in Mesoamerica which included the detection of residual DDT in environmental (soil) and biological samples (fish tissue and children's blood). This program was carried out in communities from Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. This paper presents the first report of that program. As expected, the results show that the levels for [summation operator] DDT in soil (outdoor or indoor) and fish samples in the majority of the locations studied are below guidelines. However, in some locations, we found children with high concentrations of DDT as in Mexico (mean level 50.2 ng/mL). Furthermore, in some communities and for some matrices, the DDT/DDE quotient is higher than one and this may reflect a recent DDT exposure. Therefore, more efforts are needed to avoid exposure and to prevent the reintroduction of DDT into the region. In this regard it is important to know that under the surveillance of PAHO and with the support of UNEP, a regional program in Mesoamerica for the collection and disposal of DDT and other POPs stockpiles is in progress. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  17. Synchrotron-based X-ray fluorescence imaging and elemental mapping from biological samples

    Energy Technology Data Exchange (ETDEWEB)

    D Rao; M Swapna; R Cesareo; A Brunetti; T Akatsuka; T Yuasa; T Takeda; G Gigante

    2011-12-31

    The present study utilized the new hard X-ray microspectroscopy beamline facility, X27A, available at NSLS, BNL, USA, for elemental mapping. This facility provided the primary beam in a small spot of the order of {approx}10 {mu}m, for focussing. With this spatial resolution and high flux throughput, the synchrotron-based X-ray fluorescent intensities for Mn, Fe, Zn, Cr, Ti and Cu were measured using a liquid-nitrogen-cooled 13-element energy-dispersive high-purity germanium detector. The sample is scanned in a 'step-and-repeat' mode for fast elemental mapping measurements and generated elemental maps at 8, 10 and 12 keV, from a small animal shell (snail). The accumulated trace elements, from these biological samples, in small areas have been identified. Analysis of the small areas will be better suited to establish the physiology of metals in specific structures like small animal shell and the distribution of other elements.

  18. Towards a system level understanding of non-model organisms sampled from the environment: a network biology approach.

    Science.gov (United States)

    Williams, Tim D; Turan, Nil; Diab, Amer M; Wu, Huifeng; Mackenzie, Carolynn; Bartie, Katie L; Hrydziuszko, Olga; Lyons, Brett P; Stentiford, Grant D; Herbert, John M; Abraham, Joseph K; Katsiadaki, Ioanna; Leaver, Michael J; Taggart, John B; George, Stephen G; Viant, Mark R; Chipman, Kevin J; Falciani, Francesco

    2011-08-01

    The acquisition and analysis of datasets including multi-level omics and physiology from non-model species, sampled from field populations, is a formidable challenge, which so far has prevented the application of systems biology approaches. If successful, these could contribute enormously to improving our understanding of how populations of living organisms adapt to environmental stressors relating to, for example, pollution and climate. Here we describe the first application of a network inference approach integrating transcriptional, metabolic and phenotypic information representative of wild populations of the European flounder fish, sampled at seven estuarine locations in northern Europe with different degrees and profiles of chemical contaminants. We identified network modules, whose activity was predictive of environmental exposure and represented a link between molecular and morphometric indices. These sub-networks represented both known and candidate novel adverse outcome pathways representative of several aspects of human liver pathophysiology such as liver hyperplasia, fibrosis, and hepatocellular carcinoma. At the molecular level these pathways were linked to TNF alpha, TGF beta, PDGF, AGT and VEGF signalling. More generally, this pioneering study has important implications as it can be applied to model molecular mechanisms of compensatory adaptation to a wide range of scenarios in wild populations.

  19. Towards a system level understanding of non-model organisms sampled from the environment: a network biology approach.

    Directory of Open Access Journals (Sweden)

    Tim D Williams

    2011-08-01

    Full Text Available The acquisition and analysis of datasets including multi-level omics and physiology from non-model species, sampled from field populations, is a formidable challenge, which so far has prevented the application of systems biology approaches. If successful, these could contribute enormously to improving our understanding of how populations of living organisms adapt to environmental stressors relating to, for example, pollution and climate. Here we describe the first application of a network inference approach integrating transcriptional, metabolic and phenotypic information representative of wild populations of the European flounder fish, sampled at seven estuarine locations in northern Europe with different degrees and profiles of chemical contaminants. We identified network modules, whose activity was predictive of environmental exposure and represented a link between molecular and morphometric indices. These sub-networks represented both known and candidate novel adverse outcome pathways representative of several aspects of human liver pathophysiology such as liver hyperplasia, fibrosis, and hepatocellular carcinoma. At the molecular level these pathways were linked to TNF alpha, TGF beta, PDGF, AGT and VEGF signalling. More generally, this pioneering study has important implications as it can be applied to model molecular mechanisms of compensatory adaptation to a wide range of scenarios in wild populations.

  20. Full-field quantitative phase imaging by white-light interferometry with active phase stabilization and its application to biological samples

    Science.gov (United States)

    Li, Xinhong; Yamauchi, Toyohiko; Iwai, Hidenao; Yamashita, Yutaka; Zhang, Haijun; Hiruma, Teruo

    2006-06-01

    We report a Koehler-illumination-based full-field, actively stabilized, low-coherence phase-shifting interferometer, which is built on a white-light Michelson interferometer. By using a phase-stepping technique we can obtain full-field phase images of the sample. An actively stabilized phase-lock circuit is employed in the system to reduce phase noise. An application to human epithelial cells (HeLa cells) is achieved in our experiment. The advancement of this technique rests in its ability to take images of unstained biological samples quantitatively and on a nanometer scale.

  1. Believe it or not: Moving non-biological stimuli believed to have human origin can be represented as human movement.

    Science.gov (United States)

    Gowen, E; Bolton, E; Poliakoff, E

    2016-01-01

    Does our brain treat non-biological movements (e.g. moving abstract shapes or robots) in the same way as human movements? The current work tested whether the movement of a non-biological rectangular object, believed to be based on a human action is represented within the observer's motor system. A novel visuomotor priming task was designed to pit true imitative compatibility, due to human action representation against more general stimulus response compatibility that has confounded previous belief experiments. Stimulus response compatibility effects were found for the object. However, imitative compatibility was found when participants repeated the object task with the belief that the object was based on a human finger movement, and when they performed the task viewing a real human hand. These results provide the first demonstration that non-biological stimuli can be represented as a human movement if they are believed to have human agency and have implications for interactions with technology and robots.

  2. Copper, chromium, manganese, iron, nickel, and zinc levels in biological samples of diabetes mellitus patients.

    Science.gov (United States)

    Kazi, Tasneem Gul; Afridi, Hassan Imran; Kazi, Naveed; Jamali, Mohammad Khan; Arain, Mohammad Bilal; Jalbani, Nussarat; Kandhro, Ghulam Abbas

    2008-04-01

    There is accumulating evidence that the metabolism of several trace elements is altered in diabetes mellitus and that these nutrients might have specific roles in the pathogenesis and progress of this disease. The aim of present study was to compare the level of essential trace elements, chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn) in biological samples (whole blood, urine, and scalp hair) of patients who have diabetes mellitus type 2 (n = 257), with those of nondiabetic control subjects (n = 166), age ranged (45-75) of both genders. The element concentrations were measured by means of an atomic absorption spectrophotometer after microwave-induced acid digestion. The validity and accuracy was checked by conventional wet-acid-digestion method and using certified reference materials. The overall recoveries of all elements were found in the range of (97.60-99.49%) of certified values. The results of this study showed that the mean values of Zn, Mn, and Cr were significantly reduced in blood and scalp-hair samples of diabetic patients as compared to control subjects of both genders (p < 0.001). The urinary levels of these elements were found to be higher in the diabetic patients than in the age-matched healthy controls. In contrast, high mean values of Cu and Fe were detected in scalp hair and blood from patients versus the nondiabetic subjects, but the differences found in blood samples was not significant (p < 0.05). These results are consistent with those obtained in other studies, confirming that deficiency and efficiency of some essential trace metals may play a role in the development of diabetes mellitus.

  3. Biologic effect of a hybrid preparation of human chorionic gonadotropin in human subjects.

    Science.gov (United States)

    Rosemberg, E

    1982-01-01

    Alpha and beta-hCG subunits were recombined generating a hybrid hCG preparation (AB1ER-CR-2XY) which met the required specifications of a pharmaceutical product. The biologic activity contained in each vial of AB1ER-CR-2XY was equivalent to 10 000IU of hCG-IS. This preparation was given as a single dose of 10 000IU by the i.m. route to four female subjects presenting unexplained infertility. The hCG hybrid was demonstrated to effect gonadal stimulation in humans.

  4. Genetic identification of missing persons: DNA analysis of human remains and compromised samples.

    Science.gov (United States)

    Alvarez-Cubero, M J; Saiz, M; Martinez-Gonzalez, L J; Alvarez, J C; Eisenberg, A J; Budowle, B; Lorente, J A

    2012-01-01

    Human identification has made great strides over the past 2 decades due to the advent of DNA typing. Forensic DNA typing provides genetic data from a variety of materials and individuals, and is applied to many important issues that confront society. Part of the success of DNA typing is the generation of DNA databases to help identify missing persons and to develop investigative leads to assist law enforcement. DNA databases house DNA profiles from convicted felons (and in some jurisdictions arrestees), forensic evidence, human remains, and direct and family reference samples of missing persons. These databases are essential tools, which are becoming quite large (for example the US Database contains 10 million profiles). The scientific, governmental and private communities continue to work together to standardize genetic markers for more effective worldwide data sharing, to develop and validate robust DNA typing kits that contain the reagents necessary to type core identity genetic markers, to develop technologies that facilitate a number of analytical processes and to develop policies to make human identity testing more effective. Indeed, DNA typing is integral to resolving a number of serious criminal and civil concerns, such as solving missing person cases and identifying victims of mass disasters and children who may have been victims of human trafficking, and provides information for historical studies. As more refined capabilities are still required, novel approaches are being sought, such as genetic testing by next-generation sequencing, mass spectrometry, chip arrays and pyrosequencing. Single nucleotide polymorphisms offer the potential to analyze severely compromised biological samples, to determine the facial phenotype of decomposed human remains and to predict the bioancestry of individuals, a new focus in analyzing this type of markers.

  5. In-focus electron microscopy of frozen-hydrated biological samples with a Boersch phase plate

    Energy Technology Data Exchange (ETDEWEB)

    Barton, B.; Rhinow, D.; Walter, A.; Schroeder, R. [Max Planck Institute of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main (Germany); Benner, G.; Majorovits, E.; Matijevic, M.; Niebel, H. [Carl Zeiss NTS GmbH, D-73447 Oberkochen (Germany); Mueller, H.; Haider, M. [CEOS GmbH, Englerstr. 26, 69126 Heidleberg (Germany); Lacher, M.; Schmitz, S.; Holik, P. [Caesar Research Center, Ludwig-Erhard-Allee 2, D-53175 Bonn (Germany); Kuehlbrandt, W., E-mail: werner.kuehlbrandt@mpibp-frankfurt.mpg.de [Max Planck Institute of Biophysics, Max-von-Laue Str. 3, 60438 Frankfurt am Main (Germany)

    2011-12-15

    We report the implementation of an electrostatic Einzel lens (Boersch) phase plate in a prototype transmission electron microscope dedicated to aberration-corrected cryo-EM. The combination of phase plate, C{sub s} corrector and Diffraction Magnification Unit (DMU) as a new electron-optical element ensures minimal information loss due to obstruction by the phase plate and enables in-focus phase contrast imaging of large macromolecular assemblies. As no defocussing is necessary and the spherical aberration is corrected, maximal, non-oscillating phase contrast transfer can be achieved up to the information limit of the instrument. A microchip produced by a scalable micro-fabrication process has 10 phase plates, which are positioned in a conjugate, magnified diffraction plane generated by the DMU. Phase plates remained fully functional for weeks or months. The large distance between phase plate and the cryo sample permits the use of an effective anti-contaminator, resulting in ice contamination rates of <0.6 nm/h at the specimen. Maximal in-focus phase contrast was obtained by applying voltages between 80 and 700 mV to the phase plate electrode. The phase plate allows for in-focus imaging of biological objects with a signal-to-noise of 5-10 at a resolution of 2-3 nm, as demonstrated for frozen-hydrated virus particles and purple membrane at liquid-nitrogen temperature. -- Highlights: Black-Right-Pointing-Pointer We implement an electrostatic Boersch phase plate into a dedicated prototypical TEM. Black-Right-Pointing-Pointer Phase contrast aberration-corrected electron microscope (PACEM) includes a diffraction magnification unit (DMU). Black-Right-Pointing-Pointer DMU minimizes obstruction of low spatial frequencies by the phase plate. Black-Right-Pointing-Pointer In-focus phase contrast generation is demonstrated for frozen-hydrated biological specimens.

  6. Determination of As, Cd, Cu, Hg and Pb in biological samples by modern electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sardans, Jordi, E-mail: j.sardans@creaf.uab.ca [Ecophysiological and Global Change Unit CSIC-CREAF, Edifici C, Universitat Autonoma de Barcelona, Bellaterra 08193, Barcelona (Spain); Montes, Fernando [Departamento de Ciencias Analiticas, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/ Senda del Rey 9. 28040 Madrid (Spain); Penuelas, Josep [Ecophysiological and Global Change Unit CSIC-CREAF, Edifici C, Universitat Autonoma de Barcelona, Bellaterra 08193, Barcelona (Spain)

    2010-02-15

    Pollution from heavy metals has increased in recent decades and has become an important concern for environmental agencies. Arsenic, cadmium, copper, mercury and lead are among the trace elements that have the greatest impact and carry the highest risk to human health. Electrothermal atomic absorption spectrometry (ETAAS) has long been used for trace element analyses and over the past few years, the main constraints of atomic absorption spectrometry (AAS) methods, namely matrix interferences that provoked high background absorption and interferences, have been reduced. The use of new, more efficient modifiers and in situ trapping methods for stabilization and pre-concentration of these analytes, progress in control of atomization temperatures, new designs of atomizers and advances in methods to correct background spectral interferences have permitted an improvement in sensitivity, an increase in detection power, reduction in sample manipulation, and increase in the reproducibility of the results. These advances have enhanced the utility of Electrothermal atomic absorption spectrometry (ETAAS) for trace element determination at mug L{sup -1} levels, especially in difficult matrices, giving rise to greater reproducibility, lower economic cost and ease of sample pre-treatment compared to other methods. Moreover, the recent introduction of high resolution continuum source Electrothermal atomic absorption spectrometry (HR-CS-ETAAS) has facilitated direct solid sampling, reducing background noise and opening the possibility of achieving even more rapid quantitation of some elements. The incorporation of flow injection analysis (FIA) systems for automation of sample pre-treatment, as well as chemical vapor generation renders (ETAAS) into a feasible option for detection of As and Hg in environmental and food control studies wherein large numbers of samples can be rapidly analyzed. A relatively inexpensive approach with low sample consumption provide additional advantages

  7. Decommissioning samples from the Ft. Lewis, WA, solvent refined coal pilot plant: chemical analysis and biological testing

    Energy Technology Data Exchange (ETDEWEB)

    Weimer, W.C.; Wright, C.W.

    1985-10-01

    This report presents the results from chemical analyses and limited biological assays of three sets of samples from the Ft. Lewis, WA solvent refined coal (SRC) pilot plant. The samples were collected during the process of decommissioning this facility. Chemical composition was determined for chemical class fractions of the samples by using high-resolution gas chromatography (GC), high-resolution GC/mass spectrometry (MS) and high-resolution MS. Biological activity was measuring using both the histidine reversion microbial mutagenicity assay with Salmonella typhimurium, TA98 and an initiation/promotion mouse-skin tumorigenicity assay. 19 refs., 7 figs., 27 tabs.

  8. Rapid Preparation Methods of Biological Samples for Ionic Compounds Using Ion Exchange Type Monolithic Silica Spin Column

    OpenAIRE

    宮崎, 将太; 山田, 智子; 太田, 茂徳; 斉藤, 剛; 奈女良, 昭; 大平, 真義

    2010-01-01

    We developed a device comprising a spin column packed with ion exchange type (SCX and SAX) monolithic silica for extracting ionic compounds from biological samples. The methods involving the use of these spin column are not useful for the extraction of ionic analytes, but are highly reproducible for the analysis in serum and urine. This spin column enabled sample preparation in less than 10 min. Handling such as sample loading, washing, and elution of analytes, was exhibited by the centrifuga...

  9. Nanoparticle sensor for label free detection of swine DNA in mixed biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Ali, M E; Hashim, U [Institute of Nano Electronic Engineering (INNE), Universiti Malaysia Perlis, Lot 104-108, Tingkat 1, Block A, Taman Pertiwi Indah, Jalan Kangar-Alor Star, Seriab, 01000 Kangar, Perlis (Malaysia); Mustafa, S; Che Man, Y B; Yusop, M H M [Halal Products Research Institute, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Bari, M F [School of Materials Engineering, University Malaysia Perlis, Seriab 01000, Kangar, Perlis (Malaysia); Islam, Kh N [Department of Preclinical Sciences, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Hasan, M F, E-mail: uda@unimap.edu.my [Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)

    2011-05-13

    We used 40 {+-} 5 nm gold nanoparticles (GNPs) as colorimetric sensor to visually detect swine-specific conserved sequence and nucleotide mismatch in PCR-amplified and non-amplified mitochondrial DNA mixtures to authenticate species. Colloidal GNPs changed color from pinkish-red to gray-purple in 2 mM PBS. Visually observed results were clearly reflected by the dramatic reduction of surface plasmon resonance peak at 530 nm and the appearance of new features in the 620-800 nm regions in their absorption spectra. The particles were stabilized against salt-induced aggregation upon the adsorption of single-stranded DNA. The PCR products, without any additional processing, were hybridized with a 17-base probe prior to exposure to GNPs. At a critical annealing temperature (55 {sup 0}C) that differentiated matched and mismatched base pairing, the probe was hybridized to pig PCR product and dehybridized from the deer product. The dehybridized probe stuck to GNPs to prevent them from salt-induced aggregation and retained their characteristic red color. Hybridization of a 27-nucleotide probe to swine mitochondrial DNA identified them in pork-venison, pork-shad and venison-shad binary admixtures, eliminating the need of PCR amplification. Thus the assay was applied to authenticate species both in PCR-amplified and non-amplified heterogeneous biological samples. The results were determined visually and validated by absorption spectroscopy. The entire assay (hybridization plus visual detection) was performed in less than 10 min. The LOD (for genomic DNA) of the assay was 6 {mu}g ml{sup -1} swine DNA in mixed meat samples. We believe the assay can be applied for species assignment in food analysis, mismatch detection in genetic screening and homology studies between closely related species.

  10. Nanoparticle sensor for label free detection of swine DNA in mixed biological samples

    Science.gov (United States)

    Ali, M. E.; Hashim, U.; Mustafa, S.; Che Man, Y. B.; Yusop, M. H. M.; Bari, M. F.; Islam, Kh N.; Hasan, M. F.

    2011-05-01

    We used 40 ± 5 nm gold nanoparticles (GNPs) as colorimetric sensor to visually detect swine-specific conserved sequence and nucleotide mismatch in PCR-amplified and non-amplified mitochondrial DNA mixtures to authenticate species. Colloidal GNPs changed color from pinkish-red to gray-purple in 2 mM PBS. Visually observed results were clearly reflected by the dramatic reduction of surface plasmon resonance peak at 530 nm and the appearance of new features in the 620-800 nm regions in their absorption spectra. The particles were stabilized against salt-induced aggregation upon the adsorption of single-stranded DNA. The PCR products, without any additional processing, were hybridized with a 17-base probe prior to exposure to GNPs. At a critical annealing temperature (55 °C) that differentiated matched and mismatched base pairing, the probe was hybridized to pig PCR product and dehybridized from the deer product. The dehybridized probe stuck to GNPs to prevent them from salt-induced aggregation and retained their characteristic red color. Hybridization of a 27-nucleotide probe to swine mitochondrial DNA identified them in pork-venison, pork-shad and venison-shad binary admixtures, eliminating the need of PCR amplification. Thus the assay was applied to authenticate species both in PCR-amplified and non-amplified heterogeneous biological samples. The results were determined visually and validated by absorption spectroscopy. The entire assay (hybridization plus visual detection) was performed in less than 10 min. The LOD (for genomic DNA) of the assay was 6 µg ml - 1 swine DNA in mixed meat samples. We believe the assay can be applied for species assignment in food analysis, mismatch detection in genetic screening and homology studies between closely related species.

  11. Electronic noses for monitoring benzene occupational exposure in biological samples of Egyptian workers

    Directory of Open Access Journals (Sweden)

    Ehab I. Mohamed

    2013-02-01

    Full Text Available Objectives: Benzene is commonly emitted in several industries, leading to widespread environmental and occupational exposure hazards. While less toxic solvents have been substituted for benzene, it is still a component of petroleum products and is a trace impurity in industrial products resulting in continued higher occupational exposures in industrial settings in developing countries. Materials and Methods: We investigated the potential use of an electronic nose (e-nose to monitor the headspace volatiles in biological samples from benzene-exposed Egyptian workers and non-exposed controls. The study population comprised 150 non-smoking male workers exposed to benzene and an equal number of matching non-exposed controls. We determined biomarkers of benzene used to estimate exposure and risk including: benzene in exhaled air and blood; and its urinary metabolites such as phenol and muconic acid using gas chromatography technique and a portable e-nose. Results: The average benzene concentration measured in the ambient air of the workplace of all studied industrial settings in Alexandria, Egypt; was 97.56±88.12 μg/m3 (range: 4.69–260.86 μg/m3. Levels of phenol and muconic acid were signifi cantly (p < 0.001 higher in both blood and urine of benzene-exposed workers as compared to non-exposed controls. Conclusions: The e-nose technology has successfully classifi ed and distinguished benzene-exposed workers from non-exposed controls for all measured samples of blood, urine and the exhaled air with a very high degree of precision. Thus, it will be a very useful tool for the low-cost mass screening and early detection of health hazards associated with the exposure to benzene in the industry.

  12. Nanoparticle sensor for label free detection of swine DNA in mixed biological samples.

    Science.gov (United States)

    Ali, M E; Hashim, U; Mustafa, S; Man, Y B Che; Yusop, M H M; Bari, M F; Islam, Kh N; Hasan, M F

    2011-05-13

    We used 40 ± 5 nm gold nanoparticles (GNPs) as colorimetric sensor to visually detect swine-specific conserved sequence and nucleotide mismatch in PCR-amplified and non-amplified mitochondrial DNA mixtures to authenticate species. Colloidal GNPs changed color from pinkish-red to gray-purple in 2 mM PBS. Visually observed results were clearly reflected by the dramatic reduction of surface plasmon resonance peak at 530 nm and the appearance of new features in the 620-800 nm regions in their absorption spectra. The particles were stabilized against salt-induced aggregation upon the adsorption of single-stranded DNA. The PCR products, without any additional processing, were hybridized with a 17-base probe prior to exposure to GNPs. At a critical annealing temperature (55 °C) that differentiated matched and mismatched base pairing, the probe was hybridized to pig PCR product and dehybridized from the deer product. The dehybridized probe stuck to GNPs to prevent them from salt-induced aggregation and retained their characteristic red color. Hybridization of a 27-nucleotide probe to swine mitochondrial DNA identified them in pork-venison, pork-shad and venison-shad binary admixtures, eliminating the need of PCR amplification. Thus the assay was applied to authenticate species both in PCR-amplified and non-amplified heterogeneous biological samples. The results were determined visually and validated by absorption spectroscopy. The entire assay (hybridization plus visual detection) was performed in less than 10 min. The LOD (for genomic DNA) of the assay was 6 µg ml(-1) swine DNA in mixed meat samples. We believe the assay can be applied for species assignment in food analysis, mismatch detection in genetic screening and homology studies between closely related species.

  13. [Human papillomavirus infection, a possible biological marker of sexual behavior among university students].

    Science.gov (United States)

    Sánchez-Alemán, Miguel A; Uribe-Salas, Felipe; Conde-González, Carlos J

    2002-01-01

    To estimate the prevalence of Human papillomavirus (HPV) among university students and to use it as a biological marker to assess sexual behavior. A cross-sectional study was carried out between 2000 and 2001 among 194 students at Universidad Autónoma del Estado de Morelos, Mexico. A data collection instrument was applied and genital samples were taken to detect oncogenic HPV DNA. Data were analyzed using the chi-squared test and odds ratios. Overall HPV prevalence was 14.4%. Women who had had two or more sexual partners during the previous year showed a greater risk of HPV infection (OR 6.0, 95% CI 1.7-21.1), as did women who had used oral contraceptives and spermicides at their latest intercourse (OR 3.0, 95% CI 1.0-8.7). Males who consumed cocaine were at a greater risk of HPV infection (OR 7.6, 95% CI 1.3-45.1). HPV prevalence is relatively high. HPV is a reliable biological marker of sexual behavior among females. A greater sample size may be needed to assess its reliability among men.

  14. Kinetic spectrophotometric method for the determination of morphine in biological samples

    Science.gov (United States)

    Sheibani, A.; Shishehbore, M. Reza; Mirparizi, E.

    2010-10-01

    In this paper a simple, selective and inexpensive kinetic method was developed for the determination of morphine based on its inhibitory effect on the Janus green-bromate system in sulfuric acid media. The reaction was monitored spectrophotometrically at 618 nm by a fixed time method. The effect of different parameters such as concentration of reactants and temperature on the rate of reaction was investigated and optimum conditions were obtained. The calibration curve was linear in the concentration range 0.07-7.98 mg L -1 of morphine, and detection limit of the method was 3.0 × 10 -2 mg L -1. The relative standard deviation for five determinations of 3.74 mg L -1 of morphine was 0.57%. Finally, the proposed method was successfully applied to the determination of morphine in human urine and serum as real samples.

  15. Development of novel separation techniques for biological samples in capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Huan -Tsung [Iowa State Univ., Ames, IA (United States)

    1994-07-27

    This dissertation includes three different topics: general introduction of capillary electrophoresis (CE); gradient in CE and CE in biological separations; and capillary gel electrophoresis (CGE) for DNA separation. Factors such as temperature, viscosity, pH, and the surface of capillary walls affecting the separation performance are demonstrated. A pH gradient between 3.0 and 5.2 is useful to improve the resolution among eight different organic acids. A flow gradient due to the change in the concentration of surfactant, which is able to coat to the capillary wall to change the flow rate and its direction, is also shown as a good way to improve the resolution for organic compounds. A temperature gradient caused by joule heat is shown by voltage programming to enhance the resolution and shorten the separation time for several phenolic compounds. The author also shows that self-regulating dynamic control of electroosmotic flow in CE by simply running separation in different concentrations of surfactant has less matrix effect on the separation performance. One of the most important demonstrations in this dissertation is that the author proposes on-column reaction which gives several advantages including the use of a small amount of sample, low risk of contamination, and time saving and kinetic features. The author uses this idea with laser induced fluorescence (LIF) as a detection mode to detect an on-column digestion of sub-ng of protein. This technique also is applied to single cell analysis in the group.

  16. Analysis of six relevant toxaphene congeners in biological samples using ion trap MS/MS.

    Science.gov (United States)

    Gouteux, Bruno; Lebeuf, Michel; Trottier, Steve; Gagné, Jean-Pierre

    2002-10-01

    The quantification of six polychlorinated bornanes (CHBs) was studied using ion trap MS/MS. The significance of the selection of parent ions (Ip) and daughter ions (Id) on the detection of these toxaphene congeners was assessed in standard solution and biological samples. Our results indicate that different Ip and Id, selected at either low or high mass-to-charge (m/z) ratios, influence drastically the response factor of the CHBs and the chemical noise observed. For the octachlorinated toxaphene congeners (Parlar-26 (P-26), Parlar-40/41 (P-40/41), Parlar-44 (P-44)), the detection performance of the ion trap MS/MS is similar whether Ip and Id were chosen at low or high m/z ratios. However, the selection of Ip and Id at high m/z ratios clearly enhances the detection of the nonachlorinated toxaphene congeners (Parlar-50 (P-50), Parlar-62 (P-62)). The improved method, which selects Ip and Id at low m/z ratios for P-26, P-40/41 and P-44 and at high m/z ratios for P-50 and P-62, permitted to obtain low detection limits as well as repeatable and accurate results.

  17. Development of a new catalase activity assay for biological samples using optical CUPRAC sensor

    Science.gov (United States)

    Bekdeşer, Burcu; Özyürek, Mustafa; Güçlü, Kubilay; Alkan, Fulya Üstün; Apak, Reşat

    2014-11-01

    A novel catalase activity assay was developed for biological samples (liver and kidney tissue homogenates) using a rapid and low-cost optical sensor-based ‘cupric reducing antioxidant capacity' (CUPRAC) method. The reagent, copper(II)-neocuproine (Cu(II)-Nc) complex, was immobilized onto a cation-exchanger film of Nafion, and the absorbance changes associated with the formation of the highly-colored Cu(I)-Nc chelate as a result of reaction with hydrogen peroxide (H2O2) was measured at 450 nm. When catalase was absent, H2O2 produced the CUPRAC chromophore, whereas catalase, being an effective H2O2 scavenger, completely annihilated the CUPRAC signal due to H2O2. Thus, the CUPRAC absorbance due to H2O2 oxidation concomitant with Cu(I)-Nc formation decreased proportionally with catalase. The developed sensor gave a linear response over a wide concentration range of H2O2 (0.68-78.6 μM). This optical sensor-based method applicable to tissue homogenates proved to be efficient for low hydrogen peroxide concentrations (physiological and nontoxic levels) to which the widely used UV method is not accurately responsive. Thus, conventional problems of the UV method arising from relatively low sensitivity and selectivity, and absorbance disturbance due to gaseous oxygen evolution were overcome. The catalase findings of the proposed method for tissue homogenates were statistically alike with those of HPLC.

  18. Cyclopentanone thiosemicarbazone, a new complexing agent for copper determination in biological samples by adsorptive stripping voltammetry.

    Science.gov (United States)

    Mahajan, Rakesh Kumar; Walia, T P S; Sumanjit; Lobana, T S

    2006-03-01

    A selective and sensitive stripping voltammetric method for the determination of trace amounts of copper(II) with cyclopentanone thiosemicarbazone (CPTSC) is presented. The method is based on the adsorptive accumulation of the resulting copper-CPTSC complex on a hanging mercury drop electrode, followed by the stripping voltammetric measurements at the reduction current of the adsorbed complex at -0.37 V vs. Ag/AgCl. The optimal conditions for the stripping analysis of copper include pH 9.3, deposition time of 120 s, and a deposition potential of -0.1 V (vs. Ag/AgCl). The peak current is linearly proportional to the copper concentration over a range 3.14 x 10(-9) M to 1.57 x 10(-6) M with a limit of detection of 1.57 x 10(-9) M. The technique has been applied to the determination of copper in biological samples, like urine and whole blood.

  19. Metabolic adaptation of a human pathogen during chronic infections - a systems biology approach

    DEFF Research Database (Denmark)

    Thøgersen, Juliane Charlotte

    by classical molecular biology approaches where genes and reactions typically are investigated in a one to one relationship. This thesis is an example of how mathematical approaches and modeling can facilitate new biologi-­‐ cal understanding and provide new surprising ideas to important biological processes....... modeling to uncover how human pathogens adapt to the human host. Pseudomonas aeruginosa infections in cystic fibrosis patients are used as a model system for under-­‐ standing these adaptation processes. The exploratory systems biology approach facilitates identification of important phenotypes...

  20. Frontiers in the bioarchaeology of stress and disease: cross-disciplinary perspectives from pathophysiology, human biology, and epidemiology.

    Science.gov (United States)

    Klaus, Haagen D

    2014-10-01

    Over the last four decades, bioarchaeology has experienced significant technical growth and theoretical maturation. Early 21st century bioarchaeology may also be enhanced from a renewed engagement with the concept of biological stress. New insights on biological stress and disease can be gained from cross-disciplinary perspectives regarding human skeletal variation and disease. First, pathophysiologic and molecular signaling mechanisms can provide more precise understandings regarding formation of pathological phenotypes in bone. Using periosteal new bone formation as an example, various mechanisms and pathways are explored in which new bone can be formed under conditions of biological stress, particularly in bone microenvironments that involve inflammatory changes. Second, insights from human biology are examined regarding some epigenetic factors and disease etiology. While epigenetic effects on stress and disease outcomes appear profoundly influential, they are mostly invisible in skeletal tissue. However, some indirect and downstream effects, such as the developmental origins of adult health outcomes, may be partially observable in bioarchaeological data. Emerging perspectives from the human microbiome are also considered. Microbiomics involves a remarkable potential to understand ancient biology, disease, and stress. Third, tools from epidemiology are examined that may aid bioarchaeologists to better cope with some of the inherent limitations of skeletal samples to better measure and quantify the expressions of skeletal stress markers. Such cross-disciplinary synergisms hopefully will promote more complete understandings of health and stress in bioarchaeological science.

  1. Spatially robust estimates of biological nitrogen (N) fixation imply substantial human alteration of the tropical N cycle

    OpenAIRE

    Sullivan, Benjamin W.; Smith, W. Kolby; Alan R. Townsend; Nasto, Megan K.; Sasha C. Reed; Chazdon, Robin L; Cleveland, Cory C

    2014-01-01

    Biological nitrogen fixation (BNF) is the largest natural source of new nitrogen (N) to terrestrial ecosystems. Tropical forest ecosystems are a putative global hotspot of BNF, but direct, spatially explicit measurements in the biome are virtually nonexistent. Nonetheless, robust estimates of tropical forest BNF are critical for understanding how these important ecosystems may respond to global change and assessing human perturbations to the N cycle. Here, we introduce a spatial sampling meth...

  2. Particle-based N-linked glycan analysis of selected proteins from biological samples using nonglycosylated binders.

    Science.gov (United States)

    Sroka-Bartnicka, Anna; Karlsson, Isabella; Ndreu, Lorena; Quaranta, Alessandro; Pijnappel, Matthijs; Thorsén, Gunnar

    2017-01-05

    Glycosylation is one of the most common and important post-translational modifications, influencing both the chemical and the biological properties of proteins. Studying the glycosylation of the entire protein population of a sample can be challenging because variations in the concentrations of certain proteins can enhance or obscure changes in glycosylation. Furthermore, alterations in the glycosylation pattern of individual proteins, exhibiting larger variability in disease states, have been suggested as biomarkers for different types of cancer, as well as inflammatory and neurodegenerative diseases. In this paper, we present a rapid and efficient method for glycosylation analysis of individual proteins focusing on changes in the degree of fucosylation or other alterations to the core structure of the glycans, such as the presence of bisecting N-acetylglucosamines and a modified degree of branching. Streptavidin-coated magnetic beads are used in combination with genetically engineered immunoaffinity binders, called VHH antibody fragments. A major advantage of the VHHs is that they are nonglycosylated; thus, enzymatic release of glycans from the targeted protein can be performed directly on the beads. After deglycosylation, the glycans are analyzed by MALDI-TOF-MS. The developed method was evaluated concerning its specificity, and thereafter implemented for studying the glycosylation pattern of two different proteins, alpha-1-antitrypsin and transferrin, in human serum and cerebrospinal fluid. To our knowledge, this is the first example of a protein array-type experiment that employs bead-based immunoaffinity purification in combination with mass spectrometry analysis for fast and efficient glycan analysis of individual proteins in biological fluid. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  3. State of the art of environmentally friendly sample preparation approaches for determination of PBDEs and metabolites in environmental and biological samples: A critical review.

    Science.gov (United States)

    Berton, Paula; Lana, Nerina B; Ríos, Juan M; García-Reyes, Juan F; Altamirano, Jorgelina C

    2016-01-28

    Green chemistry principles for developing methodologies have gained attention in analytical chemistry in recent decades. A growing number of analytical techniques have been proposed for determination of organic persistent pollutants in environmental and biological samples. In this light, the current review aims to present state-of-the-art sample preparation approaches based on green analytical principles proposed for the determination of polybrominated diphenyl ethers (PBDEs) and metabolites (OH-PBDEs and MeO-PBDEs) in environmental and biological samples. Approaches to lower the solvent consumption and accelerate the extraction, such as pressurized liquid extraction, microwave-assisted extraction, and ultrasound-assisted extraction, are discussed in this review. Special attention is paid to miniaturized sample preparation methodologies and strategies proposed to reduce organic solvent consumption. Additionally, extraction techniques based on alternative solvents (surfactants, supercritical fluids, or ionic liquids) are also commented in this work, even though these are scarcely used for determination of PBDEs. In addition to liquid-based extraction techniques, solid-based analytical techniques are also addressed. The development of greener, faster and simpler sample preparation approaches has increased in recent years (2003-2013). Among green extraction techniques, those based on the liquid phase predominate over those based on the solid phase (71% vs. 29%, respectively). For solid samples, solvent assisted extraction techniques are preferred for leaching of PBDEs, and liquid phase microextraction techniques are mostly used for liquid samples. Likewise, green characteristics of the instrumental analysis used after the extraction and clean-up steps are briefly discussed.

  4. Probing Human NK Cell Biology Using Human Immune System (HIS) Mice.

    Science.gov (United States)

    Li, Yan; Di Santo, James P

    2016-01-01

    Our incomplete understanding of the mechanisms that orchestrate human lymphocyte differentiation and condition human immune responses is in part due to the limited access to normal human tissue samples that can inform on these complex processes. In addition, in vitro culture conditions fail to recapitulate the three-dimensional microenvironments that influence cell-cell interactions and impact on immune outcomes. Small animals provide a preclinical model to dissect and probe immunity and over the past decades, development of immunodeficient hosts that can be engrafted with human hematopoietic precursors and mature cells have led to the development of new in vivo models to study human lymphocyte development and function. Natural killer (NK) cells are implicated in the recognition and elimination of pathogen-infected and transformed cells and belong to a family of diverse innate lymphoid cells (ILCs) that provide early immune defense against disease. Here, we summarize the use of humanized mouse models for the study of NK cell and group 1 ILCs and their respective roles in immunity and tissue homeostasis.

  5. Scientific controversies on biological knowledge construction: investigating a continued formation course for teachers with respect for human biological evolution

    Directory of Open Access Journals (Sweden)

    Marcelo Erdmann Bulla

    2016-08-01

    Full Text Available The research here presented has as central theme the human biological evolution, its scientific controversies and the continued formation of science and biology teachers. We evaluate the development of a teaching sequence on the topic, emphasizing the scientific controversy regarding the supposed fossil hominid Ardipithecus ramidus (“Ardi” in a continued formation course for teachers of science and biology of basic public network Cascavel-PR and region. The empirical work involved collecting data from the responses provided by teachers to an initial questionnaire and a final. The analysis and data discussion has highlighted the importance of scientific controversy for the development of scientific knowledge and the urgency to insert the contents of human evolution in subjects on the initial formation of courses in licentiate of Biological Sciences. It is necessary also to offer continued formation courses to include such content for teachers already inserted in schools. We conclude that teaching biology and science using scientific controversies may be in satisfactory teaching tool to introduce the history and nature of science, since scientific activity is permeated by conflicts.

  6. SLEPR: a sample-level enrichment-based pathway ranking method -- seeking biological themes through pathway-level consistency.

    Science.gov (United States)

    Yi, Ming; Stephens, Robert M

    2008-09-26

    Analysis of microarray and other high throughput data often involves identification of genes consistently up or down-regulated across samples as the first step in extraction of biological meaning. This gene-level paradigm can be limited as a result of valid sample fluctuations and biological complexities. In this report, we describe a novel method, SLEPR, which eliminates this limitation by relying on pathway-level consistencies. Our method first selects the sample-level differentiated genes from each individual sample, capturing genes missed by other analysis methods, ascertains the enrichment levels of associated pathways from each of those lists, and then ranks annotated pathways based on the consistency of enrichment levels of individual samples from both sample classes. As a proof of concept, we have used this method to analyze three public microarray datasets with a direct comparison with the GSEA method, one of the most popular pathway-level analysis methods in the field. We found that our method was able to reproduce the earlier observations with significant improvements in depth of coverage for validated or expected biological themes, but also produced additional insights that make biological sense. This new method extends existing analyses approaches and facilitates integration of different types of HTP data.

  7. SLEPR: a sample-level enrichment-based pathway ranking method -- seeking biological themes through pathway-level consistency.

    Directory of Open Access Journals (Sweden)

    Ming Yi

    Full Text Available Analysis of microarray and other high throughput data often involves identification of genes consistently up or down-regulated across samples as the first step in extraction of biological meaning. This gene-level paradigm can be limited as a result of valid sample fluctuations and biological complexities. In this report, we describe a novel method, SLEPR, which eliminates this limitation by relying on pathway-level consistencies. Our method first selects the sample-level differentiated genes from each individual sample, capturing genes missed by other analysis methods, ascertains the enrichment levels of associated pathways from each of those lists, and then ranks annotated pathways based on the consistency of enrichment levels of individual samples from both sample classes. As a proof of concept, we have used this method to analyze three public microarray datasets with a direct comparison with the GSEA method, one of the most popular pathway-level analysis methods in the field. We found that our method was able to reproduce the earlier observations with significant improvements in depth of coverage for validated or expected biological themes, but also produced additional insights that make biological sense. This new method extends existing analyses approaches and facilitates integration of different types of HTP data.

  8. Dimensional comparison between amplitude-modulation atomic force microscopy and scanning ion conductance microscopy of biological samples

    Science.gov (United States)

    Kim, Joonhui; Choi, MyungHoon; Jung, Goo-Eun; Rahim Ferhan, Abdul; Cho, Nam-Joon; Cho, Sang-Joon

    2016-08-01

    The range of scanning probe microscopy (SPM) applications for atomic force microscopy (AFM) is expanding in the biological sciences field, reflecting an increasing demand for tools that can improve our fundamental understanding of the physics behind biological systems. However, the complexity associated with applying SPM techniques in biomedical research hampers the full exploitation of its capabilities. Recently, the development of scanning ion conductance microscopy (SICM) has overcome these limitations and enabled contact-free, high resolution imaging of live biological specimens. In this work, we demonstrate the limitation of AFM for imaging biological samples in liquid due to artifacts arising from AFM tip-sample interaction, and how SICM imaging is able to overcome those limitations with contact-free scanning. We also demonstrate that SICM measurements, when compared to AFM, show better fit to the actual dimensions of the biological samples. Our results highlight the superiority of SICM imaging, enabling it to be widely adopted as a general and versatile research tool for biological studies in the nanoscale.

  9. Interests of 5th through 10th Grade Students toward Human Biology

    Science.gov (United States)

    Erten, Sinan

    2008-01-01

    This study investigated the middle and high school students' interests towards the subjects of human biology, specifically, "Human Health and Nutrition" and "Human Body and Organs." The study also investigated sources of their interests and factors that impact their interests, namely people that they interact and courses that…

  10. Polymer monolithic capillary microextraction on-line coupled with inductively coupled plasma-mass spectrometry for the determination of trace Au and Pd in biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaolan; He, Man; Chen, Beibei; Hu, Bin, E-mail: binhu@whu.edu.cn

    2014-11-01

    A novel method based on on-line polymer monolithic capillary microextraction (CME)-inductively coupled plasma mass spectrometry (ICP-MS) was developed for the determination of trace Au and Pd in biological samples. For this purpose, poly(glycidyl methacrylate-ethylene dimethacrylate) monolith was prepared and functionalized with mercapto groups. The prepared monolith exhibited good selectivity to Au and Pd, and good resistance to strong acid with a long life span. Factors affecting the extraction efficiency of CME, such as sample acidity, sample flow rate, eluent conditions and coexisting ion interference were investigated in detail. Under the optimal conditions, the limits of detection (LODs, 3σ) were 5.9 ng L{sup −1} for Au and 8.3 ng L{sup −1} for Pd, and the relative standard deviations (RSDs, c = 50 ng L{sup −1}, n = 7) were 6.5% for Au and 1.1% for Pd, respectively. The developed method was successfully applied to the determination of Au and Pd in human urine and serum samples with the recovery in the range of 84–118% for spiked samples. The developed on-line polymer monolithic CME-ICP-MS method has the advantages of rapidity, simplicity, low sample/reagent consumption, high sensitivity and is suitable for the determination of trace Au and Pd in biological samples with limited amount available and complex matrix. - Highlights: • An on-line CME-ICP-MS method was developed for Au and Pd analysis in human fluids. • Poly(GMA-EDMA-SH) monolith exhibited good selectivity for Au/Pd and acid-resistance. • The method is rapid, simple, and sensitive with low sample/reagents consumption.

  11. 33S nuclear magnetic resonance spectroscopy of biological samples obtained with a laboratory model 33S cryogenic probe.

    Science.gov (United States)

    Hobo, Fumio; Takahashi, Masato; Saito, Yuta; Sato, Naoki; Takao, Tomoaki; Koshiba, Seizo; Maeda, Hideaki

    2010-05-01

    (33)S nuclear magnetic resonance (NMR) spectroscopy is limited by inherently low NMR sensitivity because of the quadrupolar moment and low gyromagnetic ratio of the (33)S nucleus. We have developed a 10 mm (33)S cryogenic NMR probe, which is operated at 9-26 K with a cold preamplifier and a cold rf switch operated at 60 K. The (33)S NMR sensitivity of the cryogenic probe is as large as 9.8 times that of a conventional 5 mm broadband NMR probe. The (33)S cryogenic probe was applied to biological samples such as human urine, bile, chondroitin sulfate, and scallop tissue. We demonstrated that the system can detect and determine sulfur compounds having SO(4)(2-) anions and -SO(3)(-) groups using the (33)S cryogenic probe, as the (33)S nuclei in these groups are in highly symmetric environments. The NMR signals for other common sulfur compounds such as cysteine are still undetectable by the (33)S cryogenic probe, as the (33)S nuclei in these compounds are in asymmetric environments. If we shorten the rf pulse width or decrease the rf coil diameter, we should be able to detect the NMR signals for these compounds.

  12. Human diseases through the lens of network biology.

    Science.gov (United States)

    Furlong, Laura I

    2013-03-01

    One of the challenges raised by next generation sequencing (NGS) is the identification of clinically relevant mutations among all the genetic variation found in an individual. Network biology has emerged as an integrative and systems-level approach for the interpretation of genome data in the context of health and disease. Network biology can provide insightful models for genetic phenomena such as penetrance, epistasis, and modes of inheritance, all of which are integral aspects of Mendelian and complex diseases. Moreover, it can shed light on disease mechanisms via the identification of modules perturbed in those diseases. Current challenges include understanding disease as a result of the interplay between environmental and genetic perturbations and assessing the impact of personal sequence variations in the context of networks. Full realization of the potential of personal genomics will benefit from network biology approaches that aim to uncover the mechanisms underlying disease pathogenesis, identify new biomarkers, and guide personalized therapeutic interventions.

  13. Multiple changes in sialic acid biology during human evolution.

    Science.gov (United States)

    Varki, Ajit

    2009-04-01

    Humans are genetically very similar to "great apes", (chimpanzees, bonobos, gorillas and orangutans), our closest evolutionary relatives. We have discovered multiple genetic and biochemical differences between humans and these other hominids, in relation to sialic acids and in Siglecs (Sia-recognizing Ig superfamily lectins). An inactivating mutation in the CMAH gene eliminated human expression of N-glycolylneuraminic acid (Neu5Gc) a major sialic acid in "great apes". Additional human-specific changes have been found, affecting at least 10 of the dietary sources, particularly red meat and milk products. As humans also have varying and sometime high levels of circulating anti-Neu5Gc antibodies, there are implications for biotechnology products, and for some human diseases associated with chronic inflammation.

  14. A reconfigurable real-time compressive-sampling camera for biological applications.

    Directory of Open Access Journals (Sweden)

    Bo Fu

    Full Text Available Many applications in biology, such as long-term functional imaging of neural and cardiac systems, require continuous high-speed imaging. This is typically not possible, however, using commercially available systems. The frame rate and the recording time of high-speed cameras are limited by the digitization rate and the capacity of on-camera memory. Further restrictions are often imposed by the limited bandwidth of the data link to the host computer. Even if the system bandwidth is not a limiting factor, continuous high-speed acquisition results in very large volumes of data that are difficult to handle, particularly when real-time analysis is required. In response to this issue many cameras allow a predetermined, rectangular region of interest (ROI to be sampled, however this approach lacks flexibility and is blind to the image region outside of the ROI. We have addressed this problem by building a camera system using a randomly-addressable CMOS sensor. The camera has a low bandwidth, but is able to capture continuous high-speed images of an arbitrarily defined ROI, using most of the available bandwidth, while simultaneously acquiring low-speed, full frame images using the remaining bandwidth. In addition, the camera is able to use the full-frame information to recalculate the positions of targets and update the high-speed ROIs without interrupting acquisition. In this way the camera is capable of imaging moving targets at high-speed while simultaneously imaging the whole frame at a lower speed. We have used this camera system to monitor the heartbeat and blood cell flow of a water flea (Daphnia at frame rates in excess of 1500 fps.

  15. Characterization of the myometrial transcriptome and biological pathways of spontaneous human labor at term

    Science.gov (United States)

    Mittal, Pooja; Romero, Roberto; Tarca, Adi L.; Gonzalez, Juan; Draghici, Sorin; Xu, Yi; Dong, Zhong; Nhan-Chang, Chia-Ling; Chaiworapongsa, Tinnakorn; Lye, Stephen; Kusanovic, Juan Pedro; Lipovich, Leonard; Mazaki-Tovi, Shali; Hassan, Sonia S.; Mesiano, Sam; Kim, Chong Jai

    2011-01-01

    Aims To characterize the transcriptome of human myometrium during spontaneous labor at term. Methods Myometrium was obtained from women with (n=19) and without labor (n=20). Illumina® HumanHT-12 microarrays were utilized. Moderated t-tests and False Discovery Rate adjustment of p-values were applied. qRT-PCR was performed for a select set of differentially expressed genes in a separate set of samples. ELISA and Western Blot were utilized to confirm differential protein production in a third sample set. Results 1) 471 genes were differentially expressed; 2) Gene Ontology analysis indicated enrichment of 103 biological processes and 18 molecular functions including: a) inflammatory response; b) cytokine activity; and c) chemokine activity; 3) systems biology pathway analysis using Signaling Pathway Impact Analysis indicated 6 significant pathways: a) cytokine-cytokine receptor interaction; b) Jak-Stat signaling; and c) complement and coagulation cascades; d) NOD-like receptor signaling pathway; e) Systemic Lupus Erythematosus; and f) Chemokine signaling pathway; 3) qRT-PCR confirmed over-expression of prostaglandin-endoperoxide synthase-2 (PTGS2/COX2), heparin binding EGF-like growth factor (HBEGF), chemokine C-C motif ligand 2 (CCL2/MCP1), leukocyte immunoglobulin-like receptor, subfamily A member 5 (LILRA5/LIR9), IL-8, IL-6, chemokine C-X-C motif ligand 6 (CXCL6/GCP2), nuclear factor of kappa light chain gene enhancer in B-cells inhibitor zeta (NFKBIZ), suppressor of cytokine signaling 3 (SOCS3) and decreased expression of FK506 binding-protein 5 (FKBP5) and aldehyde dehydrogenase (ALDH2) in labor; 4) IL-6, CXCL6, CCL2 and SOCS3 protein expression was significantly higher in the term labor group compared to the term not in labor group. Conclusions Myometrium of women in spontaneous labor at term is characterized by a stereotypic gene expression pattern consistent with over-expression of the inflammatory response and leukocyte chemotaxis. Differential gene

  16. Humidity-controlled preparation of frozen-hydrated biological samples for cryogenic coherent x-ray diffraction microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, Yuki; Nakasako, Masayoshi [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522 (Japan); RIKEN Harima Institute/SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148 (Japan)

    2012-05-15

    Coherent x-ray diffraction microscopy (CXDM) has the potential to visualize the structures of micro- to sub-micrometer-sized biological particles, such as cells and organelles, at high resolution. Toward advancing structural studies on the functional states of such particles, here, we developed a system for the preparation of frozen-hydrated biological samples for cryogenic CXDM experiments. The system, which comprised a moist air generator, microscope, micro-injector mounted on a micromanipulator, custom-made sample preparation chamber, and flash-cooling device, allowed for the manipulation of sample particles in the relative humidity range of 20%-94%rh at 293 K to maintain their hydrated and functional states. Here, we report the details of the system and the operation procedure, including its application to the preparation of a frozen-hydrated chloroplast sample. Sample quality was evaluated through a cryogenic CXDM experiment conducted at BL29XUL of SPring-8. Taking the performance of the system and the quality of the sample, the system was suitable to prepare frozen-hydrated biological samples for cryogenic CXDM experiments.

  17. The physical characteristics of human proteins in different biological functions.

    Science.gov (United States)

    Wang, Tengjiao; Tang, Hailin

    2017-01-01

    The physical properties of gene products are the foundation of their biological functions. In this study, we systematically explored relationships between physical properties and biological functions. The physical properties including origin time, evolution pressure, mRNA and protein stability, molecular weight, hydrophobicity, acidity/alkaline, amino acid compositions, and chromosome location. The biological functions are defined from 4 aspects: biological process, molecular function, cellular component and cell/tissue/organ expression. We found that the proteins associated with basic material and energy metabolism process originated earlier, while the proteins associated with immune, neurological system process etc. originated later. Tissues may have a strong influence on evolution pressure. The proteins associated with energy metabolism are double-stable. Immune and peripheral cell proteins tend to be mRNA stable/protein unstable. There are very few function items with double-unstable of mRNA and protein. The proteins involved in the cell adhesion tend to consist of large proteins with high proportion of small amino acids. The proteins of organic acid transport, neurological system process and amine transport have significantly high hydrophobicity. Interestingly, the proteins involved in olfactory receptor activity tend to have high frequency of aromatic, sulfuric and hydroxyl amino acids.

  18. Accelerator mass spectrometry analysis of 14C-oxaliplatin concentrations in biological samples and 14C contents in biological samples and antineoplastic agents

    Science.gov (United States)

    Toyoguchi, Teiko; Kobayashi, Takeshi; Konno, Noboru; Shiraishi, Tadashi; Kato, Kazuhiro; Tokanai, Fuyuki

    2015-10-01

    Accelerator mass spectrometry (AMS) is expected to play an important role in microdose trials. In this study, we measured the 14C concentration in 14C-oxaliplatin-spiked serum, urine and supernatant of fecal homogenate samples in our Yamagata University (YU) - AMS system. The calibration curves of 14C concentration in serum, urine and supernatant of fecal homogenate were linear (the correlation coefficients were ⩾0.9893), and the precision and accuracy was within the acceptance criteria. To examine a 14C content of water in three vacuum blood collection tubes and a syringe were measured. 14C was not detected from water in these devices. The mean 14C content in urine samples of 6 healthy Japanese volunteers was 0.144 dpm/mL, and the intra-day fluctuation of 14C content in urine from a volunteer was little. The antineoplastic agents are administered to the patients in combination. Then, 14C contents of the antineoplastic agents were quantitated. 14C contents were different among 10 antineoplastic agents; 14C contents of paclitaxel injection and docetaxel hydrate injection were higher than those of the other injections. These results indicate that our quantitation method using YU-AMS system is suited for microdosing studies and that measurement of baseline and co-administered drugs might be necessary for the studies in low concentrations.

  19. Accelerator mass spectrometry analysis of {sup 14}C-oxaliplatin concentrations in biological samples and {sup 14}C contents in biological samples and antineoplastic agents

    Energy Technology Data Exchange (ETDEWEB)

    Toyoguchi, Teiko, E-mail: tteiko@med.id.yamagata-u.ac.jp [Department of Pharmacy, Yamagata University Hospital, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585 (Japan); Kobayashi, Takeshi; Konno, Noboru; Shiraishi, Tadashi [Department of Pharmacy, Yamagata University Hospital, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585 (Japan); Kato, Kazuhiro; Tokanai, Fuyuki [Department of Physics, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata-shi, Yamagata 990-8560 (Japan)

    2015-10-15

    Accelerator mass spectrometry (AMS) is expected to play an important role in microdose trials. In this study, we measured the {sup 14}C concentration in {sup 14}C-oxaliplatin-spiked serum, urine and supernatant of fecal homogenate samples in our Yamagata University (YU) – AMS system. The calibration curves of {sup 14}C concentration in serum, urine and supernatant of fecal homogenate were linear (the correlation coefficients were ⩾0.9893), and the precision and accuracy was within the acceptance criteria. To examine a {sup 14}C content of water in three vacuum blood collection tubes and a syringe were measured. {sup 14}C was not detected from water in these devices. The mean {sup 14}C content in urine samples of 6 healthy Japanese volunteers was 0.144 dpm/mL, and the intra-day fluctuation of {sup 14}C content in urine from a volunteer was little. The antineoplastic agents are administered to the patients in combination. Then, {sup 14}C contents of the antineoplastic agents were quantitated. {sup 14}C contents were different among 10 antineoplastic agents; {sup 14}C contents of paclitaxel injection and docetaxel hydrate injection were higher than those of the other injections. These results indicate that our quantitation method using YU-AMS system is suited for microdosing studies and that measurement of baseline and co-administered drugs might be necessary for the studies in low concentrations.

  20. Biological Activity of Sour Cherry Fruit on the Bacterial Flora of Human Saliva in vitro

    Directory of Open Access Journals (Sweden)

    Anna Blázovics

    2012-01-01

    Full Text Available This study is the first report on the antibacterial effect of Hungarian sour cherry cultivars. Biological activity of sour cherry juices prepared from fruits Érdi jubileum, Érdi bőtermő, Maliga emléke and Kántorjánosi 3 harvested at different maturity stages was investigated on bacteria present in human saliva. The influence of sour cherry on a mixed bacterial flora of human saliva of 10 volunteers was determined by different experimental approaches. Bactericidal effects were evaluated by minimum inhibitory concentration (MIC using agar diffusion methods and by minimum bactericidal dilution (MBD assays counting the number of surviving bacterial cells in the diluted juices. Time-dependent antibacterial effects were also determined by monitoring the decrease in bacterial cell numbers after the treatment with undiluted juices. The investigated sour cherry juices displayed an impressive bactericidal effect against human saliva bacteria (10–100× reduction of cell numbers within a short time frame (10–40 min. Érdi jubileum was more effective (100 000× reduction of cell number after 270 min than the other studied cultivars. Bactericidal effect was influenced by ripening of samples of Érdi jubileum obtained at different harvesting dates. Biologically active components were effective against a large spectrum of opportunistic bacterial pathogens such as Pseudomonas, Klebsiella, Pantoea spp. and Escherichia coli, including the antibiotic-resistant Pseudomonas aeruginosa but they were ineffective against beneficial probiotic Lactobacillus spp. Results confirmed the antibacterial potential of all the investigated sour cherry fruits, therefore the consumption of the fruit or its juice for positive influence on oral hygiene is highly recommended.

  1. Dimeric ligands for GPCRs involved in human reproduction : synthesis and biological evaluation

    NARCIS (Netherlands)

    Bonger, Kimberly Michelle

    2008-01-01

    Dimeric ligands for G-protein coupled receptors that are involved in human reproduction, namely the gonadotropin releasing hormone receptor, the luteinizing hormone receptor and the follicle-stimulating hormone receptor, were synthesized and biologically evaluated.

  2. A SIMPLE COLORIMETRIC METHOD TO DETECT BIOLOGICAL EVIDENCE OF HUMAN EXPOSURE TO MICROCYSTINS

    Science.gov (United States)

    Toxic cyanobacteria are contaminants of surface waters worldwide. Microcystins are some of the most commonly detected toxins. Biological evidence of human exposure may be difficult to obtain due to limitations associated with cost, laboratory capacity, analytic support, and exp...

  3. Biological properties of dehydrated human amnion/chorion composite graft: implications for chronic wound healing.

    Science.gov (United States)

    Koob, Thomas J; Rennert, Robert; Zabek, Nicole; Massee, Michelle; Lim, Jeremy J; Temenoff, Johnna S; Li, William W; Gurtner, Geoffrey

    2013-10-01

    Human amnion/chorion tissue derived from the placenta is rich in cytokines and growth factors known to promote wound healing; however, preservation of the biological activities of therapeutic allografts during processing remains a challenge. In this study, PURION® (MiMedx, Marietta, GA) processed dehydrated human amnion/chorion tissue allografts (dHACM, EpiFix®, MiMedx) were evaluated for the presence of growth factors, interleukins (ILs) and tissue inhibitors of metalloproteinases (TIMPs). Enzyme-linked immunosorbent assays (ELISA) were performed on samples of dHACM and showed quantifiable levels of the following growth factors: platelet-derived growth factor-AA (PDGF-AA), PDGF-BB, transforming growth factor α (TGFα), TGFβ1, basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), placental growth factor (PLGF) and granulocyte colony-stimulating factor (GCSF). The ELISA assays also confirmed the presence of IL-4, 6, 8 and 10, and TIMP 1, 2 and 4. Moreover, the relative elution of growth factors into saline from the allograft ranged from 4% to 62%, indicating that there are bound and unbound fractions of these compounds within the allograft. dHACM retained biological activities that cause human dermal fibroblast proliferation and migration of human mesenchymal stem cells (MSCs) in vitro. An in vivo mouse model showed that dHACM when tested in a skin flap model caused mesenchymal progenitor cell recruitment to the site of implantation. The results from both the in vitro and in vivo experiments clearly established that dHACM contains one or more soluble factors capable of stimulating MSC migration and recruitment. In summary, PURION® processed dHACM retains its biological activities related to wound healing, including the potential to positively affect four distinct and pivotal physiological processes intimately involved in wound healing: cell proliferation, inflammation, metalloproteinase activity and recruitment of progenitor cells. This suggests

  4. Multifunctional liposomes interact with Abeta in human biological fluids: Therapeutic implications for Alzheimer's disease.

    Science.gov (United States)

    Conti, Elisa; Gregori, Maria; Radice, Isabella; Da Re, Fulvio; Grana, Denise; Re, Francesca; Salvati, Elisa; Masserini, Massimo; Ferrarese, Carlo; Zoia, Chiara Paola; Tremolizzo, Lucio

    2017-02-23

    The accumulation of extracellular amyloid beta (Abeta42) both in brain and in cerebral vessels characterizes Alzheimer's disease (AD) pathogenesis. Recently, the possibility to functionalize nanoparticles (NPs) surface with Abeta42 binding molecules, making them suitable tools for reducing Abeta42 burden has been shown effective in models of AD. Aim of this work consisted in proving that NPs might be effective in sequestering Abeta42 in biological fluids, such as CSF and plasma. This demonstration is extremely important considering that these Abeta42 pools are in continuum with the brain parenchyma with drainage of Abeta from interstitial brain tissue to blood vessel and plasma. In this work, liposomes (LIP) were functionalized as previously shown in order to promote high-affinity Abeta binding, i.e., either with, phosphatidic acid (PA), or a modified Apolipoprotein E-derived peptide (mApo), or with a curcumin derivative (TREG); Abeta42 levels were determined by ELISA in CSF and plasma samples. mApo-PA-LIP (25 and 250 μM) mildly albeit significantly sequestered Abeta42 proteins in CSF samples obtained from healthy subjects (p < 0.01). Analogously a significant binding (∼20%) of Abeta42 (p < 0.001) was demonstrated following exposure to all functionalized liposomes in plasma samples obtained from selected AD or Down's syndrome patients expressing high levels of Abeta42. The same results were obtained by quantifying Abeta42 content after removal of liposome-bound Abeta by using gel filtration chromatography or ultracentrifugation on a discontinuous sucrose density gradient. In conclusion, we demonstrate that functionalized liposomes significantly sequester Abeta42 in human biological fluids. These data may be critical for future in vivo administration tests using NPs for promoting sink effect.

  5. Biological Effects of TMPRSS2/ERG Fusion Isoforms in Human Prostate Cancer

    Science.gov (United States)

    2009-02-01

    TITLE: Biological Effects of TMPRSS2/ERG Fusion Isoforms in Human Prostate Cancer PRINCIPAL INVESTIGATOR: Jianghua Wang, M.D...6 JAN 2009 / / /4. TITLE AND SUBTITLE Biological Effects of TMPRSS2/ERG Fusion Isoforms in Human Prostate Cancer 5a. CONTRACT NUMBER W81XWH...quantitative RT-PCR arrays we have identified candidate mediators of these phenotypic effects . We propose to extend these studies to primary prostate epithelial

  6. Critical tests for determination of microbiological quality and biological activity in commercial vermicompost samples of different origins.

    Science.gov (United States)

    Grantina-Ievina, Lelde; Andersone, Una; Berkolde-Pīre, Dace; Nikolajeva, Vizma; Ievinsh, Gederts

    2013-12-01

    The aim of the present paper was to show that differences in biological activity among commercially produced vermicompost samples can be found by using a relatively simple test system consisting of microorganism tests on six microbiological media and soilless seedling growth tests with four vegetable crop species. Significant differences in biological properties among analyzed samples were evident both at the level of microbial load as well as plant growth-affecting activity. These differences were mostly manufacturer- and feedstock-associated, but also resulted from storage conditions of vermicompost samples. A mature vermicompost sample that was produced from sewage sludge still contained considerable number of Escherichia coli. Samples from all producers contained several potentially pathogenic fungal species such as Aspergillus fumigatus, Pseudallescheria boidii, Pseudallescheria fimeti, Pseudallescheria minutispora, Scedosporium apiospermum, Scedosporium prolificans, Scopulariopsis brevicaulis, Stachybotrys chartarum, Geotrichum spp., Aphanoascus terreus, and Doratomyces columnaris. In addition, samples from all producers contained plant growth-promoting fungi from the genera Trichoderma and Mortierella. The described system can be useful both for functional studies aiming at understanding of factors affecting quality characteristics of vermicompost preparations and for routine testing of microbiological quality and biological activity of organic waste-derived composts and vermicomposts.

  7. Hanging drop cultures of human testis and testis cancer samples

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Young, J; Nielsen, J E

    2014-01-01

    limited by the lack of experimental models. The aim of this study was to establish an experimental tissue culture model to maintain normal and malignant germ cells within their niche and allow investigation of treatment effects. METHODS: Human testis and testis cancer specimens from orchidectomies were...

  8. Feto-maternal biology and ethics of human society

    Science.gov (United States)

    Paulesu, Luana; Ietta, Francesca; Petraglia, Felice

    2005-01-01

    The growing interest in human reproduction and the identity of the embryo have prompted us to bring some considerations to the attention of scientists. In particular, we focus on the interactive relationship between the embryo and the mother starting from the earliest stages of development. Principles governing the acceptance and growth of the embryo in the uterus may represent a model for mutual tolerance and peaceful co-existence in human society. PMID:16232317

  9. Feto-maternal biology and ethics of human society

    Directory of Open Access Journals (Sweden)

    Petraglia Felice

    2005-10-01

    Full Text Available Abstract The growing interest in human reproduction and the identity of the embryo have prompted us to bring some considerations to the attention of scientists. In particular, we focus on the interactive relationship between the embryo and the mother starting from the earliest stages of development. Principles governing the acceptance and growth of the embryo in the uterus may represent a model for mutual tolerance and peaceful co-existence in human society.

  10. Acanthamoeba: biology and increasing importance in human health.

    Science.gov (United States)

    Khan, Naveed Ahmed

    2006-07-01

    Acanthamoeba is an opportunistic protozoan that is widely distributed in the environment and is well recognized to produce serious human infections, including a blinding keratitis and a fatal encephalitis. This review presents our current understanding of the burden of Acanthamoeba infections on human health, their pathogenesis and pathophysiology, and molecular mechanisms associated with the disease, as well as virulence traits of Acanthamoeba that may be targets for therapeutic interventions and/or the development of preventative measures.

  11. Systematic approach to optimize a pretreatment method for ultrasensitive liquid chromatography with tandem mass spectrometry analysis of multiple target compounds in biological samples.

    Science.gov (United States)

    Togashi, Kazutaka; Mutaguchi, Kuninori; Komuro, Setsuko; Kataoka, Makoto; Yamazaki, Hiroshi; Yamashita, Shinji

    2016-08-01

    In current approaches for new drug development, highly sensitive and robust analytical methods for the determination of test compounds in biological samples are essential. These analytical methods should be optimized for every target compound. However, for biological samples that contain multiple compounds as new drug candidates obtained by cassette dosing tests, it would be preferable to develop a single method that allows the determination of all compounds at once. This study aims to establish a systematic approach that enables a selection of the most appropriate pretreatment method for multiple target compounds without the use of their chemical information. We investigated the retention times of 27 known compounds under different mobile phase conditions and determined the required pretreatment of human plasma samples using several solid-phase and liquid-liquid extractions. From the relationship between retention time and recovery in a principal component analysis, appropriate pretreatments were categorized into several types. Based on the category, we have optimized a pretreatment method for the identification of three calcium channel blockers in human plasma. Plasma concentrations of these drugs in a cassette-dose clinical study at microdose level were successfully determined with a lower limit of quantitation of 0.2 pg/mL for diltiazem, 1 pg/mL for nicardipine, and 2 pg/mL for nifedipine.

  12. H2S Analysis in Biological Samples Using Gas Chromatography with Sulfur Chemiluminescence Detection

    OpenAIRE

    Vitvitsky, Victor; Banerjee, Ruma

    2015-01-01

    Hydrogen sulfide (H2S) is a metabolite and signaling molecule in biological tissues that regulates many physiological processes. Reliable and sensitive methods for H2S analysis are necessary for a better understanding of H2S biology and for the pharmacological modulation of H2S levels in vivo. In this chapter, we describe the use of gas chromatography coupled to sulfur chemiluminescence detection to measure the rates of H2S production and degradation by tissue homogenates at physiologically r...

  13. Assessment of uranium and selenium speciation in human and bacterial biological models to probe changes in their structural environment

    Energy Technology Data Exchange (ETDEWEB)

    Avoscan, L.; Milgram, S.; Untereiner, G.; Collins, R.; Khodja, H.; Carriere, M.; Gouget, B. [Lab. Pierre Sue, CEA-CNRS UMR 9956, CEA/Saclay, Gif-sur-Yvette (France); Coves, J. [Inst. de Biologie Structurale - J.-P. Ebel, Lab. des Proteines Membranaires, Grenoble (France); Hazemann, J.L. [Lab. de Geophysique Interne et Tectonopbysique, UMR CNRS/Univ. Joseph Fourier, Saint-Martin-D' Heres (France)

    2009-07-01

    This study illustrates the potential of physicochemical techniques to speciate uranium (U) and selenium (Se) in biological samples. Speciation, defined he0re as the study of structural environment, of both toxic elements, was characterized at several levels in biological media and directly in human cells or bacteria once the metal(loid)s were internalized. External speciation that is extracellular speciation in culture media was predicted by thermodynamic equilibrium computer modelling using the JChess software and validated by spectroscopic measurements (XANES and EXAFS). Internal speciation that is intracellular speciation in eukaryotic and prokaryotic cells was studied in vitro with a soil bacterium Cupriavidus metallidurans CH34 and ROS 17/2.8 osteoblasts, human cells responsible for bone formation. XANES, EXAFS, HPLC-ICP-MS and SDS-PAGE coupled to particle induced X-ray emission (PIXE) permitted the identification and quantification of complexes formed with organic or inorganic molecules and/or larger proteins. (orig.)

  14. Applying systems biology methods to the study of human physiology in extreme environments.

    Science.gov (United States)

    Edwards, Lindsay M; Thiele, Ines

    2013-03-22

    Systems biology is defined in this review as 'an iterative process of computational model building and experimental model revision with the aim of understanding or simulating complex biological systems'. We propose that, in practice, systems biology rests on three pillars: computation, the omics disciplines and repeated experimental perturbation of the system of interest. The number of ethical and physiologically relevant perturbations that can be used in experiments on healthy humans is extremely limited and principally comprises exercise, nutrition, infusions (e.g. Intralipid), some drugs and altered environment. Thus, we argue that systems biology and environmental physiology are natural symbionts for those interested in a system-level understanding of human biology. However, despite excellent progress in high-altitude genetics and several proteomics studies, systems biology research into human adaptation to extreme environments is in its infancy. A brief description and overview of systems biology in its current guise is given, followed by a mini review of computational methods used for modelling biological systems. Special attention is given to high-altitude research, metabolic network reconstruction and constraint-based modelling.

  15. Characterizing healthy samples for studies of human cognitive aging

    OpenAIRE

    Geldmacher, David S.; Levin, Bonnie E.; Wright, Clinton B.

    2012-01-01

    Characterizing the cognitive declines associated with aging, and differentiating them from the effects of disease in older adults, are important goals for human neuroscience researchers. This is also an issue of public health urgency in countries with rapidly aging populations. Progress toward understanding cognitive aging is complicated by numerous factors. Researchers interested in cognitive changes in healthy older adults need to consider these complexities when they design and interpre...

  16. Speed of human biological form and motion processing.

    Directory of Open Access Journals (Sweden)

    George Buzzell

    Full Text Available Recent work suggests that biological motion processing can begin within ~110 ms of stimulus onset, as indexed by the P1 component of the event-related potential (ERP. Here, we investigated whether modulation of the P1 component reflects configural processing alone, rather than the processing of both configuration and motion cues. A three-stimulus oddball task was employed to evaluate bottom-up processing of biological motion. Intact point-light walkers (PLWs or scrambled PLWs served as distractor stimuli, whereas point-light displays of tool motion served as standard and target stimuli. In a second experiment, the same design was used, but the dynamic stimuli were replaced with static point-light displays. The first experiment revealed that dynamic PLWs elicited a larger P1 as compared to scrambled PLWs. A similar P1 increase was also observed for static PLWs in the second experiment, indicating that these stimuli were more salient than static, scrambled PLWs. These findings suggest that the visual system can rapidly extract global form information from static PLWs and that the observed P1 effect for dynamic PLWs is not dependent on the presence of motion cues. Finally, we found that the N1 component was sensitive to dynamic, but not static, PLWs, suggesting that this component reflects the processing of both form and motion information. The sensitivity of P1 to static PLWs has implications for dynamic form models of biological motion processing that posit temporal integration of configural cues present in individual frames of PLW animations.

  17. In vivo biological response to extracorporeal shockwave therapy in human tendinopathy

    Directory of Open Access Journals (Sweden)

    CM Waugh

    2015-05-01

    Full Text Available Extracorporeal shock wave therapy (ESWT is a non-invasive treatment for chronic tendinopathies, however little is known about the in-vivo biological mechanisms of ESWT. Using microdialysis, we examined the real-time biological response of healthy and pathological tendons to ESWT. A single session of ESWT was administered to the mid-portion of the Achilles tendon in thirteen healthy individuals (aged 25.7 ± 7.0 years and patellar or Achilles tendon of six patients with tendinopathies (aged 39.0 ± 14.9 years. Dialysate samples from the surrounding peri-tendon were collected before and immediately after ESWT. Interleukins (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-17A, vascular endothelial growth factor and interferon-γ were quantified using a cytometric bead array while gelatinase activity (MMP-2 and -9 was examined using zymography. There were no statistical differences between the biological tissue response to ESWT in healthy and pathological tendons. IL-1β, IL-2, IL-6 and IL-8 were the cytokines predominantly detected in the tendon dialysate. IL-1β and IL-2 did not change significantly with ESWT. IL-6 and IL-8 concentrations were elevated immediately after ESWT and remained significantly elevated for four hours post-ESWT (p < 0.001. Pro-forms of MMP-2 and -9 also increased after ESWT (p < 0.003, whereas there were no significant changes in active MMP forms. In addition, the biological response to ESWT treatment could be differentiated between possible responders and non-responders based on a minimum 5-fold increase in any inflammatory marker or MMP from pre- to post-ESWT. Our findings provide novel evidence of the biological mechanisms underpinning ESWT in humans in vivo. They suggest that the mechanical stimulus provided by ESWT might aid tendon remodelling in tendinopathy by promoting the inflammatory and catabolic processes that are associated with removing damaged matrix constituents. The non-response of some individuals may

  18. In vivo biological response to extracorporeal shockwave therapy in human tendinopathy.

    Science.gov (United States)

    Waugh, C M; Morrissey, D; Jones, E; Riley, G P; Langberg, H; Screen, H R C

    2015-05-15

    Extracorporeal shock wave therapy (ESWT) is a non-invasive treatment for chronic tendinopathies, however little is known about the in-vivo biological mechanisms of ESWT. Using microdialysis, we examined the real-time biological response of healthy and pathological tendons to ESWT. A single session of ESWT was administered to the mid-portion of the Achilles tendon in thirteen healthy individuals (aged 25.7 ± 7.0 years) and patellar or Achilles tendon of six patients with tendinopathies (aged 39.0 ± 14.9 years). Dialysate samples from the surrounding peri-tendon were collected before and immediately after ESWT. Interleukins (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-17A, vascular endothelial growth factor and interferon-γ were quantified using a cytometric bead array while gelatinase activity (MMP-2 and -9) was examined using zymography. There were no statistical differences between the biological tissue response to ESWT in healthy and pathological tendons. IL-1β, IL-2, IL-6 and IL-8 were the cytokines predominantly detected in the tendon dialysate. IL-1β and IL-2 did not change significantly with ESWT. IL-6 and IL-8 concentrations were elevated immediately after ESWT and remained significantly elevated for four hours post-ESWT (p < 0.001). Pro-forms of MMP-2 and -9 also increased after ESWT (p < 0.003), whereas there were no significant changes in active MMP forms. In addition, the biological response to ESWT treatment could be differentiated between possible responders and non-responders based on a minimum 5-fold increase in any inflammatory marker or MMP from pre- to post-ESWT. Our findings provide novel evidence of the biological mechanisms underpinning ESWT in humans in vivo. They suggest that the mechanical stimulus provided by ESWT might aid tendon remodelling in tendinopathy by promoting the inflammatory and catabolic processes that are associated with removing damaged matrix constituents. The non-response of some individuals may help to

  19. Discoveries of rhythms in human biological functions: a historical review.

    Science.gov (United States)

    Lemmer, Björn

    2009-08-01

    Though there are very early and ancient observations on the daily variation in physiological and pathophysiological functions (e.g., bronchial asthma), more detailed and scientific reports were not published until the beginning of the 17th century. The aim of this review is to bring those reports to the attention of researchers of chronobiology and chronopharmacology. The ancient books and their contents, which constitute the basis for this review, are part of the personal library collection of the author; numerous observations and reports on biologic rhythms in man are presented here for the first time. The intent of this review is to demonstrate that the fields of chronobiology and chronopharmacology are not only a new and modern branch of science, but that it stands on the shoulders of wonderful and insightful observations and explanations made by our scientific forefathers. It is the hope that the reader will enjoy the richness of the ancient reports that contribute to our present knowledge achieved through astute early biologic rhythm research.

  20. Preference for Point-Light Human Biological Motion in Newborns: Contribution of Translational Displacement

    Science.gov (United States)

    Bidet-Ildei, Christel; Kitromilides, Elenitsa; Orliaguet, Jean-Pierre; Pavlova, Marina; Gentaz, Edouard

    2014-01-01

    In human newborns, spontaneous visual preference for biological motion is reported to occur at birth, but the factors underpinning this preference are still in debate. Using a standard visual preferential looking paradigm, 4 experiments were carried out in 3-day-old human newborns to assess the influence of translational displacement on perception…

  1. Human embryonic stem cells : advancing biology and cardiogenesis towards functional applications l

    NARCIS (Netherlands)

    Braam, Stefan Robbert

    2010-01-01

    Human embryonic stem cells (hESC) hold great potential as a model for human development, disease pathology, drug discovery and safety pharmacology. All these applications will depend on comprehensive knowledge of their biology and control of their signaling mechanisms and fate choices. To begin to a

  2. 75 FR 33312 - Indexing Structured Product Labeling for Human Prescription Drug and Biological Products; Request...

    Science.gov (United States)

    2010-06-11

    ... HUMAN SERVICES Food and Drug Administration Indexing Structured Product Labeling for Human Prescription... Evaluation and Research (CDER) and Center for Biologics Evaluation and Research (CBER) are indexing certain... class as a top priority for indexing of product labeling information. FDA is now announcing that...

  3. Preference for Point-Light Human Biological Motion in Newborns: Contribution of Translational Displacement

    Science.gov (United States)

    Bidet-Ildei, Christel; Kitromilides, Elenitsa; Orliaguet, Jean-Pierre; Pavlova, Marina; Gentaz, Edouard

    2014-01-01

    In human newborns, spontaneous visual preference for biological motion is reported to occur at birth, but the factors underpinning this preference are still in debate. Using a standard visual preferential looking paradigm, 4 experiments were carried out in 3-day-old human newborns to assess the influence of translational displacement on perception…

  4. Preconcentration and determination of heavy metals in water, sediment and biological samples

    OpenAIRE

    Shirkhanloo Hamid; Mousavi Zavvar Hassan; Rouhollahi Ahmad

    2011-01-01

    In this study, a simple, sensitive and accurate column preconcentration method was developed for the determination of Cd, Cu and Pb ions in river water, urine and sediment samples by flame atomic absorption spectrometry. The procedure is based on the retention of the analytes on a mixed cellulose ester membrane (MCEM) column from buffered sample solutions and then their elution from the column with nitric acid. Several parameters, such as pH of the sample solution, volume of the sample ...

  5. Sampling Based Trajectory Planning for Robots in Dynamic Human Environments

    DEFF Research Database (Denmark)

    Svenstrup, Mikael

    2010-01-01

    Open-ended human environments, such as pedestrian streets, hospital corridors, train stations etc., are places where robots start to emerge. Hence, being able to plan safe and natural trajectories in these dynamic environments is an important skill for future generations of robots. In this work...... method for selecting the best trajectory in the RRT, according to the cost of traversing a potential field. Furthermore the RRT expansion is enhanced to direct the search and account for the kinodynamic robot constraints. A model predictive control (MPC) approach is taken to accommodate...

  6. "Eve" in Africa: Human Evolution Meets Molecular Biology.

    Science.gov (United States)

    Seager, Robert D.

    1990-01-01

    Presented is a discussion of recent evidence on the evolution of human forms on earth gathered and evaluated using mitochondrial DNA techniques. Theories regarding the possibility that a common female ancestor existed in Africa about 200,000 years ago are discussed. A list of teaching aids is provided. (CW)

  7. Computational biology in human aging : an omics data integration approach

    NARCIS (Netherlands)

    Akker, Erik Ben van den

    2015-01-01

    Throughout this thesis, human aging and its relation to health are studied in the context of two parallel though complementary lines of research: biomarkers and genetics. The search for informative biomarkers of aging focuses on easy accessible and quantifiable substances of the body that can be u

  8. Chiral analysis of amphetamines, methadone and metabolites in biological samples by electrodriven methods.

    Science.gov (United States)

    Mandrioli, Roberto; Mercolini, Laura; Raggi, Maria A

    2011-10-01

    Amphetamines and methadone are synthetic chiral drugs with a high potential for abuse. As such, several analytical methods have been developed for their enantioseparation and analysis in biological tissues, and some of these are based on electrodriven techniques. In this review, the most important and recent of these latter methods are reviewed and their main advantages and disadvantages are discussed. Particular attention is paid to the suitability of each method for the application to the biological matrix of interest: while all methods have been successfully applied for one or more biological tissues, to reach this goal they must overcome the sensitivity problem that is common to almost all capillary electrophoretic techniques. Most methods use one or more cyclodextrin derivatives as the chiral selector, thus the separation mechanism is not particularly complicated or unusual.

  9. Sampling

    CERN Document Server

    Thompson, Steven K

    2012-01-01

    Praise for the Second Edition "This book has never had a competitor. It is the only book that takes a broad approach to sampling . . . any good personal statistics library should include a copy of this book." —Technometrics "Well-written . . . an excellent book on an important subject. Highly recommended." —Choice "An ideal reference for scientific researchers and other professionals who use sampling." —Zentralblatt Math Features new developments in the field combined with all aspects of obtaining, interpreting, and using sample data Sampling provides an up-to-date treat

  10. [Effects of culture supernatant of human amnion mesenchymal stem cells on biological characteristics of human fibroblasts].

    Science.gov (United States)

    Wu, Qi'er; Lyu, Lu; Xin, Haiming; Luo, Liang; Tong, Yalin; Mo, Yongliang; Yue, Yigang

    2016-06-01

    To investigate the effects of culture supernatant of human amnion mesenchymal stem cells (hAMSCs-CS) on biological characteristics of human fibroblasts. (1) hAMSCs were isolated from deprecated human fresh amnion tissue of placenta and then sub-cultured. The morphology of hAMSCs on culture day 3 and hAMSCs of the third passage were observed with inverted phase contrast microscope. (2) Two batches of hAMSCs of the third passage were obtained, then the expression of vimentin of cells was observed with immunofluorescence method, and the expression of cell surface marker CD90, CD73, CD105, and CD45 was detected by flow cytometer. (3) hAMSCs-CS of the third passage at culture hour 72 were collected, and the content of insulin-like growth factor Ⅰ (IGF-Ⅰ), vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), and basic fibroblast growth factor (bFGF) were detected by enzyme-linked immunosorbent assay. (4) Human fibroblasts were isolated from deprecated human fresh prepuce tissue of circumcision and then sub-cultured. Human fibroblasts of the third passage were used in the following experiments. Cells were divided into blank control group and 10%, 30%, 50%, and 70% hAMSCs-CS groups according to the random number table (the same grouping method below), with 48 wells in each group. Cells in blank control group were cultured with DMEM/F12 medium containing 2% fetal bovine serum (FBS), while cells in the latter 4 groups were cultured with DMEM/F12 medium containing corresponding volume fraction of hAMSCs-CS and 2% FBS. The proliferation activity of cells was detected by cell counting kit 8 and microplate reader at culture hour 12, 24, 48, and 72, respectively, and corresponding volume fraction of hAMSCs-CS which causing the best proliferation activity of human fibroblasts was used in the following experiments. (5) Human fibroblasts were divided into blank control group and 50% hAMSCs-CS group and treated as in (4), with 4 wells in each group, at post

  11. Integration of systems biology with organs-on-chips to humanize therapeutic development

    Science.gov (United States)

    Edington, Collin D.; Cirit, Murat; Chen, Wen Li Kelly; Clark, Amanda M.; Wells, Alan; Trumper, David L.; Griffith, Linda G.

    2017-02-01

    "Mice are not little people" - a refrain becoming louder as the gaps between animal models and human disease become more apparent. At the same time, three emerging approaches are headed toward integration: powerful systems biology analysis of cell-cell and intracellular signaling networks in patient-derived samples; 3D tissue engineered models of human organ systems, often made from stem cells; and micro-fluidic and meso-fluidic devices that enable living systems to be sustained, perturbed and analyzed for weeks in culture. Integration of these rapidly moving fields has the potential to revolutionize development of therapeutics for complex, chronic diseases, including those that have weak genetic bases and substantial contributions from gene-environment interactions. Technical challenges in modeling complex diseases with "organs on chips" approaches include the need for relatively large tissue masses and organ-organ cross talk to capture systemic effects, such that current microfluidic formats often fail to capture the required scale and complexity for interconnected systems. These constraints drive development of new strategies for designing in vitro models, including perfusing organ models, as well as "mesofluidic" pumping and circulation in platforms connecting several organ systems, to achieve the appropriate physiological relevance.

  12. Automatic instrument for chemical processing to detect microorganism in biological samples by measuring light reactions

    Science.gov (United States)

    Kelbaugh, B. N.; Picciolo, G. L.; Chappelle, E. W.; Colburn, M. E. (Inventor)

    1973-01-01

    An automated apparatus is reported for sequentially assaying urine samples for the presence of bacterial adenosine triphosphate (ATP) that comprises a rotary table which carries a plurality of sample containing vials and automatically dispenses fluid reagents into the vials preparatory to injecting a light producing luciferase-luciferin mixture into the samples. The device automatically measures the light produced in each urine sample by a bioluminescence reaction of the free bacterial adenosine triphosphate with the luciferase-luciferin mixture. The light measured is proportional to the concentration of bacterial adenosine triphosphate which, in turn, is proportional to the number of bacteria present in the respective urine sample.

  13. [Analysis of human tissue samples for volatile fire accelerants].

    Science.gov (United States)

    Treibs, Rudolf

    2014-01-01

    In police investigations of fires, the cause of a fire and the fire debris analysis regarding traces of fire accelerants are important aspects for forensic scientists. Established analytical procedures were recently applied to the remains of fire victims. When examining lung tissue samples, vapors inhaled from volatile ignitable liquids could be identified and differentiated from products of pyrolysis caused by the fire. In addition to the medico-legal results this evidence allowed to draw conclusions as to whether the fire victim was still alive when the fire started.

  14. Biological effects of Echinacea purpurea on human blood cells.

    Science.gov (United States)

    Joksić, Gordana; Petrović, Sandra; Joksić, Ivana; Leskovac, Andreja

    2009-06-01

    The aim of this study was to investigate radioprotective properties of Echinacea purpurea tablets in vivo. We analysed lymphocyte chromosome aberrations (CA), micronuclei (MN), apoptosis of leukocytes and haematological parameters in a group of radiation workers who were identified as carrying dicentric chromosomes in their lymphocytes. All radiation workers were taking two 275 mg Echinacea tablets b.i.d., according to a pharmacist's recommendation. All parameters were analysed before and after the two-week treatment. At the end of the treatment lymphocyte CA frequency dropped significantly, and the number of apoptotic cells increased. The inverse lymphocyte-to-granulocyte ratio at the beginning of the study changed to normal at its end. In conclusion, biological effects observed after administration of Echinacea purpurea preparation suggest that it may be beneficial for the prevention of adverse health effects in workers exposed to ionising radiation.

  15. Human mast cell tryptase in biology and medicine.

    Science.gov (United States)

    Vitte, Joana

    2015-01-01

    The most abundant prestored enzyme of human mast cell secretory granules is the serine-protease tryptase. In humans, there are four tryptase isoforms, but only two of them, namely the alpha and beta tryptases, are known as medically important. Low levels of continuous tryptase production as an immature monomer makes up the major part of the baseline serum tryptase levels, while transient release of mature tetrameric tryptase upon mast cell degranulation accounts for the anaphylactic rise of serum tryptase levels. Serum tryptase determination contributes to the diagnosis or monitoring of mast cell disorders including mast cell activation - induced anaphylaxis, mastocytosis and a number of myeloproliferative conditions with mast cell lineage involvement. Baseline serum tryptase levels are predictive of the severity risk in some allergic conditions.

  16. Constant-Distance Mode Nanospray Desorption Electrospray Ionization Mass Spectrometry Imaging of Biological Samples with Complex Topography

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Son N.; Liyu, Andrey V.; Chu, Rosalie K.; Anderton, Christopher R.; Laskin, Julia

    2017-01-17

    A new approach for constant distance mode mass spectrometry imaging of biological samples using nanospray desorption electrospray ionization (nano-DESI MSI) was developed by integrating a shear-force probe with nano-DESI probe. The technical concept and basic instrumental setup as well as general operation of the system are described. Mechanical dampening of resonant oscillations due to the presence of shear forces between the probe and the sample surface enables constant-distance imaging mode via a computer controlled closed feedback loop. The capability of simultaneous chemical and topographic imaging of complex biological samples is demonstrated using living Bacillus Subtilis ATCC 49760 colonies on agar plates. The constant-distance mode nano-DESI MSI enabled imaging of many metabolites including non-ribosomal peptides (surfactin, plipastatin and iturin) and iron-bound heme on the surface of living bacterial colonies ranging in diameter from 10 mm to 13 mm with height variations of up to 0.8 mm above the agar plate. Co-registration of ion images to topographic images provided higher-contrast images. Constant-mode nano-DESI MSI is ideally suited for imaging biological samples of complex topography in their native state.

  17. Nitrous oxide determination in postmortem biological samples: a case of serial fatal poisoning in a public hospital.

    Science.gov (United States)

    Poli, Diana; Gagliano-Candela, Roberto; Strisciullo, Giuseppe; Colucci, Anna P; Strada, Luigi; Laviola, Domenica; Goldoni, Matteo; Mutti, Antonio

    2010-01-01

    In a public hospital, eight cases of fatal poisoning by nitrous oxide (N(2)O) occurred under oxygen administration, due to an erroneous swapping of the lines in the gas system. The aim of the study was to clarify the factors involved in asphyxia by characterizing gases from different lines and measuring N(2)O concentrations in postmortem biological samples from bodies exhumed. Analyses carried out on the gas system confirmed the erroneous substitution of O(2) line with N(2)O and air line with O(2). Consequently, high N(2)O amounts were revealed in several tissues and gaseous biological samples. All specimens were analyzed by headspace gas chromatography technique. A rigorous quantitative analysis was possible only in blood (11.29-2152.04 mg/L) and urine (95.11 mg/L) and in air samples from stomach and trachea (from 5.28 to 83.63 g/m(3)). This study demonstrates that N(2)O can be detected in biological samples even 1 month after death.

  18. Constant-Distance Mode Nanospray Desorption Electrospray Ionization Mass Spectrometry Imaging of Biological Samples with Complex Topography.

    Science.gov (United States)

    Nguyen, Son N; Liyu, Andrey V; Chu, Rosalie K; Anderton, Christopher R; Laskin, Julia

    2017-01-17

    A new approach for constant-distance mode mass spectrometry imaging (MSI) of biological samples using nanospray desorption electrospray ionization (nano-DESI) was developed by integrating a shear-force probe with the nano-DESI probe. The technical concept and basic instrumental setup, as well as the general operation of the system are described. Mechanical dampening of resonant oscillations due to the presence of shear forces between the probe and the sample surface enabled the constant-distance imaging mode via a computer-controlled closed-feedback loop. The capability of simultaneous chemical and topographic imaging of complex biological samples is demonstrated using living Bacillus subtilis ATCC 49760 colonies on agar plates. The constant-distance mode nano-DESI MSI enabled imaging of many metabolites, including nonribosomal peptides (surfactin, plipastatin, and iturin) on the surface of living bacterial colonies, ranging in diameter from 10 to 13 mm, with height variations up to 0.8 mm above the agar plate. Co-registration of ion images to topographic images provided higher-contrast images. Based on this effort, constant-mode nano-DESI MSI proved to be ideally suited for imaging biological samples of complex topography in their native states.

  19. THERMOREGULATION AND HUMAN PERFORMANCE: PHYSIOLOGICAL AND BIOLOGICAL ASPECTS

    Directory of Open Access Journals (Sweden)

    Frank E Marino

    2008-12-01

    Full Text Available Vol 53 (Medicine & Sport Science This collection on the latest interpretation of research data about the relationship between thermoregulation, exercise performance and fatigue is published as the 53rd volume of Medicine and Sport Science Journal. PURPOSE The book aims to explain how the advances in technology and methodology allowed studying the affects of the changing body temperature on metabolism and the role played by the nervous system in shaping human performance under challenging thermal situations. FEATURES This publication provides different interpretations of recent research for a better understanding of the limitations of thermoregulation in nine titles. The presented titles are: The Evolutionary Basis of Thermoregulation and Exercise Performance; Comparative Thermoregulation and the Quest for Athletic Supremacy; Thermoregulation, Fatigue and Exercise Modality; Neuromuscular Response to Exercise Heat Stress; Intestinal Barrier Dysfunction, Endotoxemia and Gastrointestinal Symptoms: The 'Canary in the Coal Mine' during Exercise-Heat Stress?; Effects of Peripheral Cooling on Characteristics of Local Muscle; Cooling Interventions for the Protection and Recovery of Exercise Performance from Exercise-Induced Heat Stress; Ethnicity and Temperature Regulation; Exercise Heat Stress and Metabolism. The evidence for the human's ability to adjust their performance according to the thermal limits in order to preserve cellular homeostasis is particularly noteworthy. AUDIENCE This is a fundamental book for any students and/or researchers involved in the fields of medicine, exercise physiology and human performance with special reference to thermal regulation. ASSESSMENT This publication is a must-read text for all those working in thermal medicine, exercise physiology and human performance fields

  20. Role of Epigenetics in Biology and Human Diseases

    OpenAIRE

    Moosavi, Azam; Ardekani, Ali Motevalizadeh

    2016-01-01

    For a long time, scientists have tried to describe disorders just by genetic or environmental factors. However, the role of epigenetics in human diseases has been considered from a half of century ago. In the last decade, this subject has attracted many interests, especially in complicated disorders such as behavior plasticity, memory, cancer, autoimmune disease, and addiction as well as neurodegenerative and psychological disorders. This review first explains the history and classification o...

  1. How Parents Influence School Grades: Hints from a Sample of Adoptive and Biological Families

    Science.gov (United States)

    Johnson, Wendy; McGue, Matt; Iacono, William G.

    2007-01-01

    Using the biological and adoptive families in the Minnesota-based Sibling Interaction and Behavior Study, we investigated the associations among genetic and environmental influences on IQ, parenting, parental expectations for offspring educational attainment, engagement in school, and school grades. All variables showed substantial genetic…

  2. Microwave-ultrasound combined reactor suitable for atmospheric sample preparation procedure of biological and chemical products

    NARCIS (Netherlands)

    Lagha, A.; Chemat, S.; Bartels, P.V.; Chemat, F.

    1999-01-01

    A compact apparatus in which a specific position can be irradiated by microwaves (MW) and ultrasound (US) simultaneously has been developed. The MW-US reactor has been designed for atmospheric pressure digestion and dissolution of biological and chemical products. The reactor can treat a range of th

  3. New frontiers in human cell biology and medicine: can pluripotent stem cells deliver?

    Science.gov (United States)

    Goldstein, Lawrence S B

    2012-11-12

    Human pluripotent stem cells provide enormous opportunities to treat disease using cell therapy. But human stem cells can also drive biomedical and cell biological discoveries in a human model system, which can be directly linked to understanding disease or developing new therapies. Finally, rigorous scientific studies of these cells can and should inform the many science and medical policy issues that confront the translation of these technologies to medicine. In this paper, I discuss these issues using amyotrophic lateral sclerosis as an example.

  4. AutoMate Express™ forensic DNA extraction system for the extraction of genomic DNA from biological samples.

    Science.gov (United States)

    Liu, Jason Y; Zhong, Chang; Holt, Allison; Lagace, Robert; Harrold, Michael; Dixon, Alan B; Brevnov, Maxim G; Shewale, Jaiprakash G; Hennessy, Lori K

    2012-07-01

    The AutoMate Express™ Forensic DNA Extraction System was developed for automatic isolation of DNA from a variety of forensic biological samples. The performance of the system was investigated using a wide range of biological samples. Depending on the sample type, either PrepFiler™ lysis buffer or PrepFiler BTA™ lysis buffer was used to lyse the samples. After lysis and removal of the substrate using LySep™ column, the lysate in the sample tubes were loaded onto AutoMate Express™ instrument and DNA was extracted using one of the two instrument extraction protocols. Our study showed that DNA was recovered from as little as 0.025 μL of blood. DNA extracted from casework-type samples was free of detectable PCR inhibitors and the short tandem repeat profiles were complete, conclusive, and devoid of any PCR artifacts. The system also showed consistent performance from day-to-day operation. 2012 American Academy of Forensic Sciences. Published 2012. This article is a U.S. Government work and is in the public domain in the U.S.A.

  5. Human papillomavirus self-sampling for screening nonattenders

    DEFF Research Database (Denmark)

    Lam, Janni Uyen Hoa; Rebolj, Matejka; Ejegod, Ditte Møller

    2017-01-01

    In organized cervical screening programs, typically 25% of the invited women do not attend. The Copenhagen Self-sampling Initiative (CSi) aimed to gain experiences on participation among screening nonattenders in the Capital Region of Denmark. Here, we report on the effectiveness of different...... region of Denmark were identified via the organized national invitation module. Screening history was obtained via the nationwide pathology registry. Twenty-four thousand women were invited, and as an alternative to the regular communication platforms (letter and phone), women could request a home test...... via a mobile-friendly webpage. Instruction material and video-animation in several languages were made available online. Chi-square test was used to test differences. Out of all invited, 31.7% requested a home test, and 20% returned it to the laboratory. In addition, 10% were screened at the physician...

  6. The importance of selecting a proper biological milieu for protein corona analysis in vitro: Human plasma versus human serum.

    Science.gov (United States)

    Mirshafiee, Vahid; Kim, Raehyun; Mahmoudi, Morteza; Kraft, Mary L

    2016-06-01

    Nanoparticle (NP) exposure to biological fluids in the body results in protein binding to the NP surface, which forms a protein coating that is called the "protein corona". To simplify studies of protein-NP interactions and protein corona formation, NPs are incubated with biological solutions, such as human serum or human plasma, and the effects of this exposure are characterized in vitro. Yet, how NP exposure to these two different biological milieus affects protein corona composition and cell response has not been investigated. Here, we explore the differences between the protein coronas that form when NPs are incubated in human serum versus human plasma. NP characterization indicated that NPs that were exposed to human plasma had higher amounts of proteins bound to their surfaces, and were slightly larger in size than those exposed to human serum. In addition, significant differences in corona composition were also detected with gel electrophoresis and liquid chromatography-mass spectrometry/mass spectrometry, where a higher fraction of coagulation proteins and complement factors were found on the plasma-exposed NPs. Flow cytometry and confocal microscopy showed that the uptake of plasma-exposed NPs was higher than that of serum-exposed NPs by RAW 264.7 macrophage immune cells, but not by NIH 3T3 fibroblast cells. This difference is likely due to the elevated amounts of opsonins, such as fibrinogen, on the surfaces of the NPs exposed to plasma, but not serum, because these components trigger NP internalization by immune cells. As the human plasma better mimics the composition of the in vivo environment, namely blood, in vitro protein corona studies should employ human plasma, and not human serum, so the biological phenomena that is observed is more similar to that occurring in vivo.

  7. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  8. Reducing sample complexity of polyclonal human autoantibodies by chromatofocusing.

    Science.gov (United States)

    Hagemann, Sascha; Faude, Alexander; Rabenstein, Monika; Balzer-Geldsetzer, Monika; Nölker, Carmen; Bacher, Michael; Dodel, Richard

    2010-08-15

    Chromatofocusing was performed in order to separate a polyclonal antigen-specific mixture of human immunoglobulins (IgGs) that would then allow for further analyses of as few different IgGs as possible. Because polyclonal IgGs only differ by amino acid sequence and possible post-translational modifications but not by molecular weight, we chose chromatofocusing for protein separation by different isoelectric points. We isolated antigen-specific IgGs from commercially available intravenous immunoglobulins (IVIG) using a combination of affinity- and size exclusion-chromatography and in order to reduce the complexity of the starting material IVIG was then replaced by single-donor plasmapheresis material. Using two-dimensional gel electrophoresis (2-DE), we observed a clear decrease in the number of different light and heavy chains in the chromatofocusing peak as compared to the starting material. In parallel, we monitored slight problems with the selected peak in isoelectric focusing as the first dimension of 2-DE, displayed in by the less proper focusing of the spots. When we tested whether IgGs were binding to their specific antigen after chromatofocusing, we were able to show that they were still in native conformation. In conclusion, we showed that chromatofocusing can be used as a first step in the analysis of mixtures of very similar proteins, e.g. polyclonal IgG preparations, in order to minimize the amount of different proteins in separated fractions in a reproducible way. Copyright 2010 Elsevier B.V. All rights reserved.

  9. A high performance liquid chromatographic method of analysis of 4'-O-tetrahydropyranyladriamycin and their metabolites in biological samples.

    Science.gov (United States)

    Matsushita, Y; Iguchi, H; Kiyosaki, T; Tone, H; Ishikura, T; Takeuchi, T; Umezawa, H

    1983-07-01

    A method for measuring 4'-O-tetrahydropyranyladriamycin (THP) and its metabolites in biological samples are described. By reversed-phase high performance liquid chromatography using fluorescence detection, THP and its metabolites were all separated on a single chromatogram within 18 minutes. A linear calibration curve was obtained up to 2,000 ng/ml of THP in plasma. The recovery of THP in the analysis was more than 95% above 5 ng/ml and 87.1% even at 1.25 ng/ml. Thus the lower limit was 1.25 ng/ml in biological samples. Blood levels and urinary excretion in mice and dogs were satisfactory measured by this analytical method.

  10. Environmental Sampling Procedures and Methods to Respond to Biological Contamination (White Powder)

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.; Amidan, Brett G.; Matzke, Brett D.

    2008-11-01

    This is a contribution to the annual report for the DHS Standards Office. It summarizes statistics-focused work associated with developing validated sampling procedures and methods. The main focus is on the experimental and sampling design constructed for contamination and decontamination field tests conducted during September 2007 in a remote, unused office building on the Idaho National Laboratory site.

  11. An Activity To Demonstrate the Concept of Sampling Error for the Introductory Biology Classroom.

    Science.gov (United States)

    Rutledge, Michael L.

    2001-01-01

    This activity makes students a part of an investigation that determines the frequency of a particular plant variety in a simulated population. Provides an opportunity for students to observe the inherent variability of estimates, observe the relationship between sample size and sampling error, and consider aspects of research design. (Author/SAH)

  12. Assessment of human exposure to airborne fungi in agricultural confinements: personal inhalable sampling versus stationary sampling.

    Science.gov (United States)

    Adhikari, Atin; Reponen, Tiina; Lee, Shu-An; Grinshpun, Sergey A

    2004-01-01

    Accurate exposure assessment to airborne fungi in agricultural environments is essential for estimating the associated occupational health hazards of workers. The objective of this pilot study was to compare personal and stationary sampling for assessing farmers' exposure to airborne fungi in 3 different agricultural confinements located in Ohio, USA (hog farm, dairy farm, and grain farm), using Button Personal Inhalable Samplers. Personal exposures were measured with samplers worn by 3 subjects (each carrying 2 samplers) during 3 types of activities, including animal feeding in the hog farm, cleaning and animal handling in the dairy farm, and soybean unloading and handling in the grain farm. Simultaneously, the stationary measurements were performed using 5 static Button Samplers and 1 revolving Button Sampler. The study showed that the total concentration of airborne fungi ranged from 1.4 x 10(4)-1.2 x 10(5) spores m(-3) in 3 confinements. Grain unloading and handling activity generated highest concentrations of airborne fungi compared to the other 2 activities. Prevalent airborne fungi belonged to Cladosporium, Aspergillus/Penicillium, Ascospores, smut spores, Epicoccum, Alternaria, and Basidiospores. Lower coefficients of variations were observed for the fungal concentrations measured by personal samplers (7-12%) compared to the concentrations measured by stationary samplers (27-37%). No statistically significant difference was observed between the stationary and personal measurement data for the total concentrations of airborne fungi (p > 0.05). Revolving stationary and static stationary Button Samplers demonstrated similar performance characteristics for the collection of airborne fungi. This reflects the low sensitivity of the sampler's efficiency to the wind speed and direction. The results indicate that personal exposure of agricultural workers in confinements may be adequately assessed by placing several Button Samplers simultaneously operating in a

  13. A 96-well screen filter plate for high-throughput biological sample preparation and LC-MS/MS analysis.

    Science.gov (United States)

    Peng, Sean X; Cousineau, Martin; Juzwin, Stephen J; Ritchie, David M

    2006-01-01

    A novel 96-well screen filter plate (patent pending) has been invented to eliminate a time-consuming and labor-intensive step in preparation of in vivo study samples--to remove blood or plasma clots. These clots plug the pipet tips during a manual or automated sample-transfer step causing inaccurate pipetting or total pipetting failure. Traditionally, these blood and plasma clots are removed by picking them out manually one by one from each sample tube before any sample transfer can be made. This has significantly slowed the sample preparation process and has become a bottleneck for automated high-throughput sample preparation using robotic liquid handlers. Our novel screen filter plate was developed to solve this problem. The 96-well screen filter plate consists of 96 stainless steel wire-mesh screen tubes connected to the 96 openings of a top plate so that the screen filter plate can be readily inserted into a 96-well sample storage plate. Upon insertion, the blood and plasma clots are excluded from entering the screen tube while clear sample solutions flow freely into it. In this way, sample transfer can be easily completed by either manual or automated pipetting methods. In this report, three structurally diverse compounds were selected to evaluate and validate the use of the screen filter plate. The plasma samples of these compounds were transferred and processed in the presence and absence of the screen filter plate and then analyzed by LC-MS/MS methods. Our results showed a good agreement between the samples prepared with and without the screen filter plate, demonstrating the utility and efficiency of this novel device for preparation of blood and plasma samples. The device is simple, easy to use, and reusable. It can be employed for sample preparation of other biological fluids that contain floating particulates or aggregates.

  14. Slow-spinning low-sideband HR-MAS NMR spectroscopy: delicate analysis of biological samples

    Science.gov (United States)

    Renault, Marie; Shintu, Laetitia; Piotto, Martial; Caldarelli, Stefano

    2013-11-01

    High-Resolution Magic-Angle Spinning (HR-MAS) NMR spectroscopy has become an extremely versatile analytical tool to study heterogeneous systems endowed with liquid-like dynamics. Spinning frequencies of several kHz are however required to obtain NMR spectra, devoid of spinning sidebands, with a resolution approaching that of purely isotropic liquid samples. An important limitation of the method is the large centrifugal forces that can damage the structure of the sample. In this communication, we show that optimizing the sample preparation, particularly avoiding air bubbles, and the geometry of the sample chamber of the HR-MAS rotor leads to high-quality low-sideband NMR spectra even at very moderate spinning frequencies, thus allowing the use of well-established solution-state NMR procedures for the characterization of small and highly dynamic molecules in the most fragile samples, such as live cells and intact tissues.

  15. Slow-spinning low-sideband HR-MAS NMR spectroscopy: delicate analysis of biological samples

    Science.gov (United States)

    Renault, Marie; Shintu, Laetitia; Piotto, Martial; Caldarelli, Stefano

    2013-01-01

    High-Resolution Magic-Angle Spinning (HR-MAS) NMR spectroscopy has become an extremely versatile analytical tool to study heterogeneous systems endowed with liquid-like dynamics. Spinning frequencies of several kHz are however required to obtain NMR spectra, devoid of spinning sidebands, with a resolution approaching that of purely isotropic liquid samples. An important limitation of the method is the large centrifugal forces that can damage the structure of the sample. In this communication, we show that optimizing the sample preparation, particularly avoiding air bubbles, and the geometry of the sample chamber of the HR-MAS rotor leads to high-quality low-sideband NMR spectra even at very moderate spinning frequencies, thus allowing the use of well-established solution-state NMR procedures for the characterization of small and highly dynamic molecules in the most fragile samples, such as live cells and intact tissues. PMID:24284435

  16. Prospects of use of cobalt nitrate as a contrast medium in electron microscopy of biological samples

    Directory of Open Access Journals (Sweden)

    I. O. Tikhankov

    2008-01-01

    Full Text Available The method of cobalt nitrate impregnation of ultrathin sections of plant and animal tissues, which are embedded in epoxy resin, has been worked out. Various aspects of such handling of specimens have been examined. Best conditions for the sections staining were determined. The advantage of this method was analyzed. The estimation of the possibilities to implicate this method for the morphological and histochemical study of various biological specimens has been made.

  17. Comparative systems biology between human and animal models based on next-generation sequencing methods.

    Science.gov (United States)

    Zhao, Yu-Qi; Li, Gong-Hua; Huang, Jing-Fei

    2013-04-01

    Animal models provide myriad benefits to both experimental and clinical research. Unfortunately, in many situations, they fall short of expected results or provide contradictory results. In part, this can be the result of traditional molecular biological approaches that are relatively inefficient in elucidating underlying molecular mechanism. To improve the efficacy of animal models, a technological breakthrough is required. The growing availability and application of the high-throughput methods make systematic comparisons between human and animal models easier to perform. In the present study, we introduce the concept of the comparative systems biology, which we define as "comparisons of biological systems in different states or species used to achieve an integrated understanding of life forms with all their characteristic complexity of interactions at multiple levels". Furthermore, we discuss the applications of RNA-seq and ChIP-seq technologies to comparative systems biology between human and animal models and assess the potential applications for this approach in the future studies.

  18. The Constitutive Content of the Crime of Refusal or Evasion from Collecting Biological Samples According to the New Criminal Code

    OpenAIRE

    Minodora-Ioana BALAN-RUSU

    2014-01-01

    The purpose and the objectives of the research consist of examining the constitutive content of the crime of refusal or evasion from collecting biological samples according to the New Criminal Code, thus presenting some recent examples of judicial practice that may be applied in terms of new regulations imposed by the entry into force of the New Romanian Criminal Code. The research results consist of examining the constitutive content referring to judicial practice, and highlig...

  19. Active learning not associated with student learning in a random sample of college biology courses.

    Science.gov (United States)

    Andrews, T M; Leonard, M J; Colgrove, C A; Kalinowski, S T

    2011-01-01

    Previous research has suggested that adding active learning to traditional college science lectures substantially improves student learning. However, this research predominantly studied courses taught by science education researchers, who are likely to have exceptional teaching expertise. The present study investigated introductory biology courses randomly selected from a list of prominent colleges and universities to include instructors representing a broader population. We examined the relationship between active learning and student learning in the subject area of natural selection. We found no association between student learning gains and the use of active-learning instruction. Although active learning has the potential to substantially improve student learning, this research suggests that active learning, as used by typical college biology instructors, is not associated with greater learning gains. We contend that most instructors lack the rich and nuanced understanding of teaching and learning that science education researchers have developed. Therefore, active learning as designed and implemented by typical college biology instructors may superficially resemble active learning used by education researchers, but lacks the constructivist elements necessary for improving learning.

  20. Metabolomics identifies a biological response to chronic low-dose natural uranium contamination in urine samples.

    Science.gov (United States)

    Grison, Stéphane; Favé, Gaëlle; Maillot, Matthieu; Manens, Line; Delissen, Olivia; Blanchardon, Eric; Banzet, Nathalie; Defoort, Catherine; Bott, Romain; Dublineau, Isabelle; Aigueperse, Jocelyne; Gourmelon, Patrick; Martin, Jean-Charles; Souidi, Maâmar

    2013-01-01

    Because uranium is a natural element present in the earth's crust, the population may be chronically exposed to low doses of it through drinking water. Additionally, the military and civil uses of uranium can also lead to environmental dispersion that can result in high or low doses of acute or chronic exposure. Recent experimental data suggest this might lead to relatively innocuous biological reactions. The aim of this study was to assess the biological changes in rats caused by ingestion of natural uranium in drinking water with a mean daily intake of 2.7 mg/kg for 9 months and to identify potential biomarkers related to such a contamination. Subsequently, we observed no pathology and standard clinical tests were unable to distinguish between treated and untreated animals. Conversely, LC-MS metabolomics identified urine as an appropriate biofluid for discriminating the experimental groups. Of the 1,376 features detected in urine, the most discriminant were metabolites involved in tryptophan, nicotinate, and nicotinamide metabolic pathways. In particular, N-methylnicotinamide, which was found at a level seven times higher in untreated than in contaminated rats, had the greatest discriminating power. These novel results establish a proof of principle for using metabolomics to address chronic low-dose uranium contamination. They open interesting perspectives for understanding the underlying biological mechanisms and designing a diagnostic test of exposure.

  1. A high-performance direct transmethylation method for total fatty acids assessment in biological and foodstuff samples.

    Science.gov (United States)

    Castro-Gómez, Pilar; Fontecha, Javier; Rodríguez-Alcalá, Luis M

    2014-10-01

    Isolation is the main bottleneck in the analysis of fatty acids in biological samples and foods. In the last few decades some methods described direct derivatization procedures bypassing these steps. They involve the utilization of methanolic HCL or BF3 as catalysts, but several evidences from previous works suggest these reagents are unstable, lead to the formation of artifacts and alter the distribution of specific compounds as hydroxy fatty acids or CLA. However, the main issue is that they are excellent esterification reagents but poor in transterification, being not suitable for the analysis of all lipid classes and leading to erroneous composition quantitations. The present research work is a comprehensive comparison of six general methylation protocols using base, acid or base/acid catalysts plus a proposed method in the analysis of total fatty acids in lipid standards mixtures, foodstuff and biological samples. The addition of aprotic solvents to the reaction mixture to avoid alterations was also tested. Results confirmed that procedures solely involving acid catalyst resulted in incomplete derivatizations and alteration of the fatty acid profile, partially corrected by addition of the aprotic solvent. The proposed method combining sodium methoxyde and sulfuric acid showed absence of alteration of the FAME profile and the best values for response factors (short chain fatty acids to PUFA), accuracy in the determination of total cholesterol and derivatization performance, thus showing a high reliability in the determination of the total fatty acid composition in biological samples and foods.

  2. Capillary zone electrophoresis for analysis of phytochelatins and other thiol peptides in complex biological samples derivatized with monobromobimane.

    Science.gov (United States)

    Perez-Rama, Mónica; Torres Vaamonde, Enrique; Abalde Alonso, Julio

    2005-02-01

    A new method to improve the analysis of phytochelatins and their precursors (cysteine, gamma-Glu-Cys, and glutathione) derivatized with monobromobimane (mBrB) in complex biological samples by capillary zone electrophoresis is described. The effects of the background electrolyte pH, concentration, and different organic additives (acetonitrile, methanol, and trifluoroethanol) on the separation were studied to achieve optimum resolution and number of theoretical plates of the analyzed compounds in the electropherograms. Optimum separation of the thiol peptides was obtained with 150 mM phosphate buffer at pH 1.60. Separation efficiency was improved when 2.5% v/v methanol was added to the background electrolyte. The electrophoretic conditions were 13 kV and capillary dimensions with 30 cm length from the inlet to the detector (38 cm total length) and 50 microm inner diameter. The injection was by pressure at 50 mbar for 17 s. Under these conditions, the separation between desglycyl-peptides and phytochelatins was also achieved. We also describe the optimum conditions for the derivatization of biological samples with mBrB to increase electrophoretic sensitivity and number of theoretical plates. The improved method was shown to be simple, reproducible, selective, and accurate in measuring thiol peptides in complex biological samples, the detection limit being 2.5 microM glutathione at a wavelength of 390 nm.

  3. Evaluation of cadmium, lead, nickel and zinc status in biological samples of smokers and nonsmokers hypertensive patients.

    Science.gov (United States)

    Afridi, H I; Kazi, T G; Kazi, N G; Jamali, M K; Arain, M B; Sirajuddin; Baig, J A; Kandhro, G A; Wadhwa, S K; Shah, A Q

    2010-01-01

    The objective of this study was to evaluate the association between trace and toxic elements zinc (Zn), cadmium (Cd), nickel (Ni) and lead (Pb) in biological samples (scalp hair, blood and urine) of smoker and nonsmoker hypertensive patients (n=457), residents of Hyderabad, Pakistan. For the purpose of comparison, the biological samples of age-matched healthy controls were selected as referents. The concentrations of trace and toxic elements were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference materials and by the conventional wet acid digestion method on the same certified reference materials and real samples. The recovery of all the studied elements was found to be in the range of 97.8-99.3% in certified reference materials. The results of this study showed that the mean values of Cd, Ni and Pb were significantly higher in scalp hair, blood and urine samples of both smoker and nonsmoker patients than in referents (P<0.001), whereas the concentration of Zn was lower in the scalp hair and blood, but higher in the urine samples of hypertensive patients. The deficiency of Zn and the high exposure of toxic metals as a result of tobacco smoking may be synergistic with risk factors associated with hypertension.

  4. Biological psychological and social determinants of old age: Bio-psycho-social aspects of human aging

    Directory of Open Access Journals (Sweden)

    Małgorzata Dziechciaż

    2014-11-01

    Full Text Available Biological psychological and social determinants of old age: Bio-psycho-social aspects of human aging. The aging of humans is a physiological and dynamic process ongoing with time. In accordance with most gerontologists’ assertions it starts in the fourth decade of life and leads to death. The process of human aging is complex and individualized, occurs in the biological, psychological and social sphere. Biological aging is characterized by progressive age-changes in metabolism and physicochemical properties of cells, leading to impaired self-regulation, regeneration, and to structural changes and functional tissues and organs. It is a natural and irreversible process which can run as successful aging, typical or pathological. Biological changes that occur with age in the human body affect mood, attitude to the environment, physical condition and social activity, and designate the place of seniors in the family and society. Psychical ageing refers to human awareness and his adaptability to the ageing process. Among adaptation attitudes we can differentiate: constructive, dependence, hostile towards others and towards self attitudes. With progressed age, difficulties with adjustment to the new situation are increasing, adverse changes in the cognitive and intellectual sphere take place, perception process involutes, perceived sensations and information received is lowered, and thinking processes change. Social ageing is limited to the role of an old person is culturally conditioned and may change as customs change. Social ageing refers to how a human being perceives the ageing process and how society sees it.

  5. Mitochondrial biology. Replication-transcription switch in human mitochondria.

    Science.gov (United States)

    Agaronyan, Karen; Morozov, Yaroslav I; Anikin, Michael; Temiakov, Dmitry

    2015-01-30

    Coordinated replication and expression of the mitochondrial genome is critical for metabolically active cells during various stages of development. However, it is not known whether replication and transcription can occur simultaneously without interfering with each other and whether mitochondrial DNA copy number can be regulated by the transcription machinery. We found that interaction of human transcription elongation factor TEFM with mitochondrial RNA polymerase and nascent transcript prevents the generation of replication primers and increases transcription processivity and thereby serves as a molecular switch between replication and transcription, which appear to be mutually exclusive processes in mitochondria. TEFM may allow mitochondria to increase transcription rates and, as a consequence, respiration and adenosine triphosphate production without the need to replicate mitochondrial DNA, as has been observed during spermatogenesis and the early stages of embryogenesis.

  6. Fabrication of diverse pH-sensitive functional mesoporous silica for selective removal or depletion of highly abundant proteins from biological samples.

    Science.gov (United States)

    Wang, Jiaojiao; Lan, Jingfeng; Li, Huihui; Liu, Xiaoyan; Zhang, Haixia

    2017-01-01

    In proteomic studies, poor detection of low abundant proteins is a major problem due to the presence of highly abundant proteins. Therefore, the specific removal or depletion of highly abundant proteins prior to analysis is necessary. In response to this problem, a series of pH-sensitive functional mesoporous silica materials composed of 2-(diethylamino)ethyl methacrylate and methacrylic acid units were designed and synthesized via atom transfer radical polymerization. These functional mesoporous silica materials were characterized and their ability for adsorption and separation of proteins was evaluated. Possessing a pH-sensitive feature, the synthesized functional materials showed selective adsorption of some proteins in aqueous or buffer solutions at certain pH values. The specific removal of a particular protein from a mixed protein solution was subsequently studied. The analytical results confirmed that all the target proteins (bovine serum albumin, ovalbumin, and lysozyme) can be removed by the proposed materials from a five-protein mixture in a single operation. Finally, the practical application of this approach was also evaluated by the selective removal of certain proteins from real biological samples. The results revealed that the maximum removal efficiencies of ovalbumin and lysozyme from egg white sample were obtained as 99% and 92%, respectively, while the maximum removal efficiency of human serum albumin from human serum sample was about 80% by the proposed method. It suggested that this treatment process reduced the complexity of real biological samples and facilitated the identification of hidden proteins in chromatograms. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Cytochrome c oxidase subunit 1-based human RNA quantification to enhance mRNA profiling in forensic biology

    Directory of Open Access Journals (Sweden)

    Dong Zhao

    2017-01-01

    Full Text Available RNA analysis offers many potential applications in forensic science, and molecular identification of body fluids by analysis of cell-specific RNA markers represents a new technique for use in forensic cases. However, due to the nature of forensic materials that often admixed with nonhuman cellular components, human-specific RNA quantification is required for the forensic RNA assays. Quantification assay for human RNA has been developed in the present study with respect to body fluid samples in forensic biology. The quantitative assay is based on real-time reverse transcription-polymerase chain reaction of mitochondrial RNA cytochrome c oxidase subunit I and capable of RNA quantification with high reproducibility and a wide dynamic range. The human RNA quantification improves the quality of mRNA profiling in the identification of body fluids of saliva and semen because the quantification assay can exclude the influence of nonhuman components and reduce the adverse affection from degraded RNA fragments.

  8. Human pressures predict species' geographic range size better than biological traits.

    Science.gov (United States)

    Di Marco, Moreno; Santini, Luca

    2015-06-01

    Geographic range size is the manifestation of complex interactions between intrinsic species traits and extrinsic environmental conditions. It is also a fundamental ecological attribute of species and a key extinction risk correlate. Past research has primarily focused on the role of biological and environmental predictors of range size, but macroecological patterns can also be distorted by human activities. Here, we analyse the role of extrinsic (biogeography, habitat state, climate, human pressure) and intrinsic (biology) variables in predicting range size of the world's terrestrial mammals. In particular, our aim is to compare the predictive ability of human pressure vs. species biology. We evaluated the ability of 19 intrinsic and extrinsic variables in predicting range size for 4867 terrestrial mammals. We repeated the analyses after excluding restricted-range species and performed separate analyses for species in different biogeographic realms and taxonomic groups. Our model had high predictive ability and showed that climatic variables and human pressures are the most influential predictors of range size. Interestingly, human pressures predict current geographic range size better than biological traits. These findings were confirmed when repeating the analyses on large-ranged species, individual biogeographic regions and individual taxonomic groups. Climatic and human impacts have determined the extinction of mammal species in the past and are the main factors shaping the present distribution of mammals. These factors also affect other vertebrate groups globally, and their influence on range size may be similar as well. Measuring climatic and human variables can allow to obtain approximate range size estimations for data-deficient and newly discovered species (e.g. hundreds of mammal species worldwide). Our results support the need for a more careful consideration of the role of climate change and human impact - as opposed to species biological

  9. Automatic sampling for unbiased and efficient stereological estimation using the proportionator in biological studies

    DEFF Research Database (Denmark)

    Gardi, Jonathan Eyal; Nyengaard, Jens Randel; Gundersen, Hans Jørgen Gottlieb

    2008-01-01

    cerebellum, total number of orexin positive neurons in transgenic mice brain, and estimating the absolute area and the areal fraction of β islet cells in dog pancreas.  The proportionator was at least eight times more efficient (precision and time combined) than traditional computer controlled sampling.......Quantification of tissue properties is improved using the general proportionator sampling and estimation procedure: automatic image analysis and non-uniform sampling with probability proportional to size (PPS). The complete region of interest is partitioned into fields of view, and every field...

  10. Fluorometric quantification of protoporphyrin IX in biological skin samples from in vitro penetration/permeation studies

    Directory of Open Access Journals (Sweden)

    Fábia Cristina Rossetti

    2010-12-01

    Full Text Available A fluorometric analytical method was developed for quantification of protoporphyrin IX (PpIX in skin samples and receptor phase solution after in vitro cutaneous penetration/permeation studies. Analytical conditions used were: excitation and emission wavelengths: 400 nm and 632 nm; bandwidth: 0.5 nm; excitation and emission slits: 10/10. PpIX was recovered from two different layers of skin, the stratum corneum (SC and the epidermis plus dermis ([E+D], by vortex homogenization, probe and bath sonication, using DMSO as an extraction solvent. The detection and quantification limits were 0.002 and 0.005 μg/mL, respectively. The assay was linear from 0.005 - 0.5 μg/mL. The within-day and between-day assay precision and accuracy in DMSO and receptor phase solution were each studied at the two concentration levels 0.04 and 0.2 μg/mL, and 0.01 and 0.08 μg/mL, respectively. The coefficients of variation and deviation from the theoretical values were lower than 5%. The skin recovery of PpIX from SC and [E+D] layers using two different concentrations (0.5 and 1.0 μg/mL were all above 90.0%. The method described has potential application to in vitro penetration/permeation studies of PpIX using porcine skin as a biological membrane model.Um método analítico por espectrofluorimetria foi desenvolvido para quantificar a protoporfirina IX (Pp IX em amostras de pele e fase receptora após a realização de testes in vitro de penetração/permeação cutâneas. As condições analíticas utilizadas foram: comprimentos de onda de excitação e emissão: 400 nm e 632 nm; largura de banda: 0,5 nm; fendas de excitação e emissão: 10/10. A PpIX foi extraída de amostras de estrato córneo (EC e da epiderme sem estrato córneo + derme ([E+D] através da agitação em vórtex e sonicação por haste e banho, utilizando-se o DMSO como solvente extrator. O limite de detecção e quantificação foram, respectivamente, de 0,002 e 0,005 μg/mL. O método mostrou

  11. Environmental contaminants in water, sediment and biological samples from Playa Lakes in southeastern New Mexico - 1992

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Sediment, water, bird tissue, and invertebrates were collected from 10 playa lakes in Southeastern New Mexico in 1991 and 1992. These samples were analyzed for a...

  12. MORPHIN: a web tool for human disease research by projecting model organism biology onto a human integrated gene network.

    Science.gov (United States)

    Hwang, Sohyun; Kim, Eiru; Yang, Sunmo; Marcotte, Edward M; Lee, Insuk

    2014-07-01

    Despite recent advances in human genetics, model organisms are indispensable for human disease research. Most human disease pathways are evolutionally conserved among other species, where they may phenocopy the human condition or be associated with seemingly unrelated phenotypes. Much of the known gene-to-phenotype association information is distributed across diverse databases, growing rapidly due to new experimental techniques. Accessible bioinformatics tools will therefore facilitate translation of discoveries from model organisms into human disease biology. Here, we present a web-based discovery tool for human disease studies, MORPHIN (model organisms projected on a human integrated gene network), which prioritizes the most relevant human diseases for a given set of model organism genes, potentially highlighting new model systems for human diseases and providing context to model organism studies. Conceptually, MORPHIN investigates human diseases by an orthology-based projection of a set of model organism genes onto a genome-scale human gene network. MORPHIN then prioritizes human diseases by relevance to the projected model organism genes using two distinct methods: a conventional overlap-based gene set enrichment analysis and a network-based measure of closeness between the query and disease gene sets capable of detecting associations undetectable by the conventional overlap-based methods. MORPHIN is freely accessible at http://www.inetbio.org/morphin.

  13. Evaluation of the biological differences of canine and human factor VIII in gene delivery: Implications in human hemophilia treatment

    Science.gov (United States)

    The canine is the most important large animal model for testing novel hemophilia A(HA) treatment. It is often necessary to use canine factor VIII (cFIII) gene or protein for the evaluation of HA treatment in the canine model. However, the different biological properties between cFVIII and human FVII...

  14. Sources of technical variability in quantitative LC-MS proteomics: human brain tissue sample analysis.

    Science.gov (United States)

    Piehowski, Paul D; Petyuk, Vladislav A; Orton, Daniel J; Xie, Fang; Moore, Ronald J; Ramirez-Restrepo, Manuel; Engel, Anzhelika; Lieberman, Andrew P; Albin, Roger L; Camp, David G; Smith, Richard D; Myers, Amanda J

    2013-05-03

    To design a robust quantitative proteomics study, an understanding of both the inherent heterogeneity of the biological samples being studied as well as the technical variability of the proteomics methods and platform is needed. Additionally, accurately identifying the technical steps associated with the largest variability would provide valuable information for the improvement and design of future processing pipelines. We present an experimental strategy that allows for a detailed examination of the variability of the quantitative LC-MS proteomics measurements. By replicating analyses at different stages of processing, various technical components can be estimated and their individual contribution to technical variability can be dissected. This design can be easily adapted to other quantitative proteomics pipelines. Herein, we applied this methodology to our label-free workflow for the processing of human brain tissue. For this application, the pipeline was divided into four critical components: Tissue dissection and homogenization (extraction), protein denaturation followed by trypsin digestion and SPE cleanup (digestion), short-term run-to-run instrumental response fluctuation (instrumental variance), and long-term drift of the quantitative response of the LC-MS/MS platform over the 2 week period of continuous analysis (instrumental stability). From this analysis, we found the following contributions to variability: extraction (72%) > instrumental variance (16%) > instrumental stability (8.4%) > digestion (3.1%). Furthermore, the stability of the platform and its suitability for discovery proteomics studies is demonstrated.

  15. Sources of Technical Variability in Quantitative LC-MS Proteomics: Human Brain Tissue Sample Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Piehowski, Paul D.; Petyuk, Vladislav A.; Orton, Daniel J.; Xie, Fang; Moore, Ronald J.; Ramirez Restrepo, Manuel; Engel, Anzhelika; Lieberman, Andrew P.; Albin, Roger L.; Camp, David G.; Smith, Richard D.; Myers, Amanda J.

    2013-05-03

    To design a robust quantitative proteomics study, an understanding of both the inherent heterogeneity of the biological samples being studied as well as the technical variability of the proteomics methods and platform is needed. Additionally, accurately identifying the technical steps associated with the largest variability would provide valuable information for the improvement and design of future processing pipelines. We present an experimental strategy that allows for a detailed examination of the variability of the quantitative LC-MS proteomics measurements. By replicating analyses at different stages of processing, various technical components can be estimated and their individual contribution to technical variability can be dissected. This design can be easily adapted to other quantitative proteomics pipelines. Herein, we applied this methodology to our label-free workflow for the processing of human brain tissue. For this application, the pipeline was divided into four critical components: Tissue dissection and homogenization (extraction), protein denaturation followed by trypsin digestion and SPE clean-up (digestion), short-term run-to-run instrumental response fluctuation (instrumental variance), and long-term drift of the quantitative response of the LC-MS/MS platform over the 2 week period of continuous analysis (instrumental stability). From this analysis, we found the following contributions to variability: extraction (72%) >> instrumental variance (16%) > instrumental stability (8.4%) > digestion (3.1%). Furthermore, the stability of the platform and its’ suitability for discovery proteomics studies is demonstrated.

  16. Oxygen bomb combustion of biological samples for inductively coupled plasma optical emission spectrometry

    Science.gov (United States)

    Souza, Gilberto B.; Carrilho, Elma Neide V. M.; Oliveira, Camila V.; Nogueira, Ana Rita A.; Nóbrega, Joaquim A.

    2002-12-01

    A rapid sample preparation method is proposed for decomposition of milk powder, corn bran, bovine and fish tissues, containing certified contents of the analytes. The procedure involves sample combustion in a commercial stainless steel oxygen bomb operating at 25 bar. Most of the samples were decomposed within 5 min. Diluted nitric acid or water-soluble tertiary amines 10% v/v were used as absorption solutions. Calcium, Cu, K, Mg, Na, P, S and Zn were recovered with the bomb washings and determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Ethanol mixed with paraffin was used as a combustion aid to allow complete combustion. A cooling step prior releasing of the bomb valve was employed to increase the efficiency of sample combustion. Iodine was also determined in milk samples spiked with potassium iodide to evaluate the volatilization and collection of iodine in amine CFA-C medium and the feasibility of its determination by ICP-OES with axial view configuration. Most of the element recoveries in the samples were between 91 and 105% and the certified and found contents exhibited a fair agreement at a 95% confidence level.

  17. The latest advancements in proteomic two-dimensional gel electrophoresis analysis applied to biological samples.

    Science.gov (United States)

    Santucci, Laura; Bruschi, Maurizio; Ghiggeri, Gian Marco; Candiano, Giovanni

    2015-01-01

    Two-dimensional gel electrophoresis (2DE) is one of the fundamental approaches in proteomics for the separation and visualization of complex protein mixtures. Proteins can be analyzed by 2DE using isoelectric focusing (IEF) in the first dimension, combined to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the second dimension, gel staining (silver and Coomassie), image analysis, and 2DE gel database. High-resolution 2DE can resolve up to 5,000 different proteins simultaneously (∼2,000 proteins routinely), and detect and quantify <1 ng of protein per spot. Here, we describe the latest developments for a more complete analysis of biological fluids.

  18. Biological Effects of Culture Substrates on Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Yohei Hayashi

    2016-01-01

    Full Text Available In recent years, as human pluripotent stem cells (hPSCs have been commonly cultured in feeder-free conditions, a number of cell culture substrates have been applied or developed. However, the functional roles of these substrates in maintaining hPSC self-renewal remain unclear. Here in this review, we summarize the types of these substrates and their effect on maintaining hPSC self-renewal. Endogenous extracellular matrix (ECM protein expression has been shown to be crucial in maintaining hPSC self-renewal. These ECM molecules interact with integrin cell-surface receptors and transmit their cellular signaling. We discuss the possible effect of integrin-mediated signaling pathways on maintaining hPSC self-renewal. Activation of integrin-linked kinase (ILK, which transmits ECM-integrin signaling to AKT (also known as protein kinase B, has been shown to be critical in maintaining hPSC self-renewal. Also, since naïve pluripotency has been widely recognized as an alternative pluripotent state of hPSCs, we discuss the possible effects of culture substrates and integrin signaling on naïve hPSCs based on the studies of mouse embryonic stem cells. Understanding the role of culture substrates in hPSC self-renewal and differentiation enables us to control hPSC behavior precisely and to establish scalable or microfabricated culture technologies for regenerative medicine and drug development.

  19. A quantum biological hypothesis of human secondary dentinogenesis.

    Science.gov (United States)

    Moss, M L; Moss-Salentijn, L; Hasselgren, G; Ling, H

    2005-01-01

    It is hypothesized that human coronal secondary dentin (SD) is a final classical mechanical (CM) response to a chain of prior quantum mechanical (QM) transductions of the information of initial CM occlusal loadings of enamel. Such CM energy is transduced into QM quanta (as protons) that are translocated centripetally via clustered water (CW), (as "proton wires"), that is structurally related to both enamel prism sheath and hydroxyapatite crystal hydration shells. These quanta pass into odontoblastic cell processes (OP), lying within dentinal tubules (DT). OP's contain abundant parallel arrays of cylindrical microtubules (MT). These are the sites of two further CW-related QM events: (i) proton translocation associated with conformal changes of MT tubulin protein dimers; and (ii) coherent energetic oscillations within the CW filling the MT's hollow cores. Finally, these quanta pass into the odontoblastic soma, where QM wave function collapse transduces this information into a final CM state that initiates the processes of SD formation. A critical portion of this hypothesis may be experimentally tested.

  20. A biologically plausible model of human shape symmetry perception.

    Science.gov (United States)

    Poirier, Frédéric J A M; Wilson, Hugh R

    2010-01-19

    Symmetry is usually computationally expensive to encode reliably, and yet it is relatively effortless to perceive. Here, we extend F. J. A. M. Poirier and H. R. Wilson's (2006) model for shape perception to account for H. R. Wilson and F. Wilkinson's (2002) data on shape symmetry. Because the model already accounts for shape perception, only minimal neural circuitry is required to enable it to encode shape symmetry as well. The model is composed of three main parts: (1) recovery of object position using large-scale non-Fourier V4-like concentric units that respond at the center of concentric contour segments across orientations, (2) around that recovered object center, curvature mechanisms combine multiplicatively the responses of oriented filters to encode object-centric local shape information, with a preference for convexities, and (3) object-centric symmetry mechanisms. Model and human performances are comparable for symmetry perception of shapes. Moreover, with some improvement of edge recovery, the model can encode symmetry axes in natural images such as faces.

  1. Structural biology of human H3K9 methyltransferases.

    Directory of Open Access Journals (Sweden)

    Hong Wu

    Full Text Available UNLABELLED: SET domain methyltransferases deposit methyl marks on specific histone tail lysine residues and play a major role in epigenetic regulation of gene transcription. We solved the structures of the catalytic domains of GLP, G9a, Suv39H2 and PRDM2, four of the eight known human H3K9 methyltransferases in their apo conformation or in complex with the methyl donating cofactor, and peptide substrates. We analyzed the structural determinants for methylation state specificity, and designed a G9a mutant able to tri-methylate H3K9. We show that the I-SET domain acts as a rigid docking platform, while induced-fit of the Post-SET domain is necessary to achieve a catalytically competent conformation. We also propose a model where long-range electrostatics bring enzyme and histone substrate together, while the presence of an arginine upstream of the target lysine is critical for binding and specificity. ENHANCED VERSION: This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

  2. Below the Callus Surface: Applying Paleohistological Techniques to Understand the Biology of Bone Healing in Skeletonized Human Remains.

    Science.gov (United States)

    Assis, Sandra; Keenleyside, Anne

    2016-01-01

    Bone trauma is a common occurrence in human skeletal remains. Macroscopic and imaging scrutiny is the approach most currently used to analyze and describe trauma. Nevertheless, this line of inquiry may not be sufficient to accurately identify the type of traumatic lesion and the associated degree of bone healing. To test the usefulness of histology in the examination of bone healing biology, we used an integrative approach that combines gross inspection and microscopy. Six bone samples belonging to 5 adult individuals with signs of bone trauma were collected from the Human Identified Skeletal Collection from the Museu Bocage (Lisbon, Portugal). Previous to sampling, the lesions were described according to their location, morphology, and healing status. After sampling, the bone specimens were prepared for plane light and polarized light analysis. The histological analysis was pivotal: (1) to differentiate between types of traumatic lesions; (2) to ascertain the posttraumatic interval, and (3) to diagnose other associated pathological conditions. The outer surface of a bone lesion may not give a complete picture of the biology of the tissue's response. Accordingly, microscopic analysis is essential to differentiate, characterize, and classify trauma signs. © 2016 S. Karger AG, Basel.

  3. Human urinary biomarkers of dioxin exposure: analysis by metabolomics and biologically driven data dimensionality reduction.

    Science.gov (United States)

    Jeanneret, Fabienne; Boccard, Julien; Badoud, Flavia; Sorg, Olivier; Tonoli, David; Pelclova, Daniela; Vlckova, Stepanka; Rutledge, Douglas N; Samer, Caroline F; Hochstrasser, Denis; Saurat, Jean-Hilaire; Rudaz, Serge

    2014-10-15

    Untargeted metabolomic approaches offer new opportunities for a deeper understanding of the molecular events related to toxic exposure. This study proposes a metabolomic investigation of biochemical alterations occurring in urine as a result of dioxin toxicity. Urine samples were collected from Czech chemical workers submitted to severe dioxin occupational exposure in a herbicide production plant in the late 1960s. Experiments were carried out with ultra-high pressure liquid chromatography (UHPLC) coupled to high-resolution quadrupole time-of-flight (QTOF) mass spectrometry. A chemistry-driven feature selection was applied to focus on steroid-related metabolites. Supervised multivariate data analysis allowed biomarkers, mainly related to bile acids, to be highlighted. These results supported the hypothesis of liver damage and oxidative stress for long-term dioxin toxicity. As a second step of data analysis, the information gained from the urine analysis of Victor Yushchenko after his poisoning was examined. A subset of relevant urinary markers of acute dioxin toxicity from this extreme phenotype, including glucuro- and sulfo-conjugated endogenous steroid metabolites and bile acids, was assessed for its ability to detect long-term effects of exposure. The metabolomic strategy presented in this work allowed the determination of metabolic patterns related to dioxin effects in human and the discovery of highly predictive subsets of biologically meaningful and clinically relevant compounds. These results are expected to provide valuable information for a deeper understanding of the molecular events related to dioxin toxicity. Furthermore, it presents an original methodology of data dimensionality reduction by using extreme phenotype as a guide to select relevant features prior to data modeling (biologically driven data reduction).

  4. Biospheric Life Support - integrating biological regeneration into protection of humans in space.

    Science.gov (United States)

    Rocha, Mauricio; Iha, Koshun

    2016-07-01

    A biosphere stands for a set of biomes (regional biological communities) interacting in a materially closed (though energetically open) ecological system (CES). Earth's biosphere, the thin layer of life on the planet's surface, can be seen as a natural CES- where life "consumables" are regenerated/restored via biological, geological and chemical processes. In Life Sciences, artificial CESs- local ecosystems extracts with varying scales and degrees of closure, are considered convenient/representatives objects of study. For outer space, these concepts have been applied to the issue of life support- a significant consideration as long as distance from Earth increases. In the nineties, growing on the Russian expertise on biological life support, backed by a multidisciplinary science team, the famous Biosphere 2 appeared. That private project innovated, by assembling a set of Earth biomes samples- plus an organic ag one, inside a closed Mars base-like structure, next to 1.5 ha under glass, in Arizona, US. The crew of 8 inside completed their two years contract, though facing setbacks- the system failed, e.g., to produce enough food/air supplies. But their "failures"- if this word can be fairly applied to science endeavors, were as meaningful as their achievements for the future of life support systems (LSS) research. By this period, the Russians had accumulated experience in extended orbital stays, achieving biological outcomes inside their stations- e.g. complete wheat cycles. After reaching the Moon, the US administration decided to change national priorities, putting the space program as part of a "détente" policy, to relieve international tensions. Alongside the US space shuttle program, the Russians were invited to join the new International Space Station (ISS), bringing to that pragmatic project, also their physical/chemical LSS- top air/water regenerative technology at the time. Present US policy keeps the ISS operational, extending its service past its planned

  5. Establishing a cell biology platform: isolation and preservation of human blood products

    OpenAIRE

    2014-01-01

    Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina The use of human primary cells provide researchers in different areas with irrefutable more biologically relevant data than using cell lines or animal blood cells. The work was performed in the scope of the Cell Biology Services @ CEDOC, aiming to provide viable and trustful human primary cells and products. We had three main objectives: protocol optimizations for blood cell isolation, culture and cryopre...

  6. A new liquid chromatography-tandem mass spectrometry method for determination of parabens in human placental tissue samples.

    Science.gov (United States)

    Jiménez-Díaz, I; Vela-Soria, F; Zafra-Gómez, A; Navalón, A; Ballesteros, O; Navea, N; Fernández, M F; Olea, N; Vílchez, J L

    2011-05-15

    Endocrine disruptors are a group of organic compounds widely used, which are ubiquitous in the environment and in biological samples. The main effect of these compounds is associated with their ability to mimic or block the action of natural hormones in living organisms, including humans. Parabens (esters of p-hydroxybenzoic acid) belong to this group of compounds. In this work, we propose a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to asses the presence of parabens most commonly used in industrial applications (methyl-, ethyl-, propyl- and butyl-paraben) in samples of human placental tissue. The method involves the extraction of the analytes from the samples using ethyl acetate, followed by a clean-up step using centrifugation prior to their quantification by LC-MS/MS using an atmospheric pressure chemical ionization (APCI) interface in the negative mode. Deuterated bisphenol A (BPA-d(16)) was used as surrogate. Found detection limits (LOD) ranged from 0.03 to 0.06 ng g(-1) and quantification limits (LOQ) from 0.1 to 0.2 ng g(-1), while inter- and intra-day variability was under 13.8%. The method was validated using standard addition calibration and a spike recovery assay. Recovery rates for spiked samples ranged from 82% to 108%. This method was satisfactorily applied for the determination of parabens in 50 placental tissue samples collected from women who live in the province of Granada (Spain).

  7. Towards a systems biology understanding of human health: interplay between genotype, environment and nutrition.

    Science.gov (United States)

    Desiere, Frank

    2004-01-01

    Sequencing of the human genome has opened the door to the most exciting new era for the holistic system description of human health. It is now possible to study the underlying mechanisms of human health in relation to diet and other environmental factors such as drugs and toxic pollutants. Technological advances make it feasible to envisage that in the future personalized drug treatment and dietary advice and possibly tailored food products can be used for promoting optimal health on an individual basis, in relation to genotype and lifestyle. Life-Science research has in the past very much focused on diseases and how to reestablish human health after illness. Today, the role of food and nutrition in human health and especially prevention of illness is gaining recognition. Diseases of modern civilization, such as diabetes, heart disease and cancer have been shown to be effected by dietary patterns. The risk of disease is often associated with genetic polymorphisms, but the effect is dependent on dietary intake and nutritional status. To understand the link between diet and health, nutritional-research must cover a broad range of areas, from the molecular level to whole body studies. Therefore it provides an excellent example of integrative biology requiring a systems biology approach. The current state and implications of systems biology in the understanding of human health are reviewed. It becomes clear that a complete mechanistic description of the human organism is not yet possible. However, recent advances in systems biology provide a trajectory for future research in order to improve health of individuals and populations. Disease prevention through personalized nutrition will become more important as the obvious avenue of research in life sciences and more focus will need to be put upon those natural ways of disease prevention. In particular, the new discipline of nutrigenomics, which investigates how nutrients interact with humans, taking predetermined genetic

  8. Development of a radioimmunoassay for the determination of buprenorphine in biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Debrabandere, L.; Boven, M. Van; Daenens, P. (Louvain Univ. (Belgium))

    1993-02-01

    The development of a specific and sensitive radioimmunoassay for the detection of buprenorphine in urine samples is described. With minor adjustments, the assay was also applied to the analysis for buprenorphine in plasma samples. The 2-diazobenzoic acid derivative of buprenorphine has been prepared as a hapten. The immunization of rabbits with the hapten-bovine serum albumin conjugate resulted in the production of antibodies, which cross-reacted with N-dealkylbuprenophine up to about the 90% level. The antibodies showed very low cross-reactivities with the 3-O-glucuronides and with the structural analogue etorphine. The assay was mainly used to prescreen for buprenorphine in urine samples of persons suspected of Temgesic misuse and to determine buprenorphine in plasma samples. A linear calibration graph for buprenorphine was obtained after logit-log regression. The spiking recovery study showed a linear regression. Intra-and inter-assay relative standard deviations were < 4.35 and < 6.36%, respectively. A comparison study of the high-performance liquid chromatographic determination (X) to the radioimmunoassay (Y) resulted in the following regression equation for the urine samples: Y = 1.44 + 1.64 X (n = 32; r 0.910) and Y = 0.007 + 1.58 X (n = 10; r = 0.930) for plasma specimens. The minimum detectable dose of the immunoassay was calculated to be 10 pg ml[sup -1] (Student's t-distribution, p 0.01, degrees of freedom = 8). (Author).

  9. A brief history of the Human Biology Association: 1974-2004.

    Science.gov (United States)

    Little, Michael A; James, Gary D

    2005-01-01

    Originally incorporated as the Human Biology Council in 1974, the Human Biology Association, as it has been known since 1994, has matured in the intervening 30 years to become a society that represents broadly the interests of human biologists in the U.S. and throughout the world. The purpose of this paper is to trace the development of the Association from its foundation to the present in the context of changes in the organization of the Association and in its By-Laws, officers, committees, and membership; the history of the two journals that served as the Association's official organs (Human Biology and American Journal of Human Biology); and how the annual meetings have evolved from a modest one-day plenary session to meetings that last more than two days and include a variety of scientific contributions. Highlights of the national meetings include the Raymond Pearl Memorial Lecture, the Franz Boas Distinguished Achievement Award, and the Edward E. Hunt, Jr. Student Prize. Copyright 2005 Wiley-Liss, Inc.

  10. Supercritical Fluid Extraction and Ultra Performance Liquid Chromatography of Respiratory Quinones for Microbial Community Analysis in Environmental and Biological Samples

    Directory of Open Access Journals (Sweden)

    Koichi Fujie

    2012-03-01

    Full Text Available Microbial community structure plays a significant role in environmental assessment and animal health management. The development of a superior analytical strategy for the characterization of microbial community structure is an ongoing challenge. In this study, we developed an effective supercritical fluid extraction (SFE and ultra performance liquid chromatography (UPLC method for the analysis of bacterial respiratory quinones (RQ in environmental and biological samples. RQ profile analysis is one of the most widely used culture-independent tools for characterizing microbial community structure. A UPLC equipped with a photo diode array (PDA detector was successfully applied to the simultaneous determination of ubiquinones (UQ and menaquinones (MK without tedious pretreatment. Supercritical carbon dioxide (scCO2 extraction with the solid-phase cartridge trap proved to be a more effective and rapid method for extracting respiratory quinones, compared to a conventional organic solvent extraction method. This methodology leads to a successful analytical procedure that involves a significant reduction in the complexity and sample preparation time. Application of the optimized methodology to characterize microbial communities based on the RQ profile was demonstrated for a variety of environmental samples (activated sludge, digested sludge, and compost and biological samples (swine and Japanese quail feces.

  11. Supercritical fluid extraction and ultra performance liquid chromatography of respiratory quinones for microbial community analysis in environmental and biological samples.

    Science.gov (United States)

    Hanif, Muhammad; Atsuta, Yoichi; Fujie, Koichi; Daimon, Hiroyuki

    2012-03-05

    Microbial community structure plays a significant role in environmental assessment and animal health management. The development of a superior analytical strategy for the characterization of microbial community structure is an ongoing challenge. In this study, we developed an effective supercritical fluid extraction (SFE) and ultra performance liquid chromatography (UPLC) method for the analysis of bacterial respiratory quinones (RQ) in environmental and biological samples. RQ profile analysis is one of the most widely used culture-independent tools for characterizing microbial community structure. A UPLC equipped with a photo diode array (PDA) detector was successfully applied to the simultaneous determination of ubiquinones (UQ) and menaquinones (MK) without tedious pretreatment. Supercritical carbon dioxide (scCO(2)) extraction with the solid-phase cartridge trap proved to be a more effective and rapid method for extracting respiratory quinones, compared to a conventional organic solvent extraction method. This methodology leads to a successful analytical procedure that involves a significant reduction in the complexity and sample preparation time. Application of the optimized methodology to characterize microbial communities based on the RQ profile was demonstrated for a variety of environmental samples (activated sludge, digested sludge, and compost) and biological samples (swine and Japanese quail feces).

  12. Measurement of the unstained biological sample by a novel scanning electron generation X-ray microscope based on SEM.

    Science.gov (United States)

    Ogura, Toshihiko

    2009-08-01

    We introduced a novel X-ray microscope system based on scanning electron microscopy using thin film, which enables the measurement of unstained biological samples without damage. An unstained yeast sample was adsorbed under a titanium (Ti)-coated silicon nitride (Si3N4) film 90 nm thick. The X-ray signal from the film was detected by an X-ray photodiode (PD) placed below the sample. With an electron beam at 2.6 kV acceleration and 6.75 nA current, the yeast image is obtained using the X-ray PD. The image is created by soft X-rays from the Ti layer. The Ti layer is effective in generating the characteristic 2.7-nm wavelength X-rays by the irradiation of electrons. Furthermore, we investigated the electron trajectory and the generation of the characteristic X-rays within the Ti-coated Si3N4 film by Monte Carlo simulation. Our system can be easily utilized to observe various unstained biological samples of cells, bacteria, and viruses.

  13. Diffraction enhanced imaging and x-ray fluorescence microtomography for analyzing biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, H.S.; Pereira, G.R.; Lopes, R.T. [Laboratorio de Instrumentacao Nuclear-COPPE/UFRJ-RJ (Brazil); Anjos, M.J. [Instituto de Fisica-UERJ-RJ (Brazil); Faria, P. [Instituto Nacional do Cancer-INCa-RJ (Brazil); Kellermann, G.; Perez, C.A. [Laboratorio Nacional de Luz Sincrotron-Campinas-SP (Brazil); Tirao, G. [Faculdad de Mat. Astronomia y Fisica (FAMAF), UNC. Cordoba (Argentina); Mazzaro, I. [Laboratorio de Optica de Raios X e Instrumentacao-UFPR-Curitiba-PR (Brazil); Giles, C. [Laboratorio de Cristalografia Aplicada e Raios X-UNICAMP-Campinas-SP (Brazil)

    2007-07-15

    In this work, breast tissue samples were investigated in order to verify the distribution of certain elements by x-ray fluorescence computed tomography (XRFCT) correlated with the characteristics and pathology of each tissue observed by diffraction enhanced imaging (DEI). The DEI system can show details in low attenuation tissues. It is based on the contrast imaging obtained by extinction, diffraction and refraction characteristics and can improve reduction in false positive and false negative diagnoses. XRFCT allows mapping of all elements within the sample, since even a minute fluorescence signal can be detected. DEI imaging techniques revealed the complex structure of the disease, confirmed by the histological section, and showed microstructures in all planes of the sample. The XRFCT showed the distribution of Zn, Cu and Fe at higher concentration. (authors)

  14. A combined method for correlative 3D imaging of biological samples from macro to nano scale

    Science.gov (United States)

    Kellner, Manuela; Heidrich, Marko; Lorbeer, Raoul-Amadeus; Antonopoulos, Georgios C.; Knudsen, Lars; Wrede, Christoph; Izykowski, Nicole; Grothausmann, Roman; Jonigk, Danny; Ochs, Matthias; Ripken, Tammo; Kühnel, Mark P.; Meyer, Heiko

    2016-10-01

    Correlative analysis requires examination of a specimen from macro to nano scale as well as applicability of analytical methods ranging from morphological to molecular. Accomplishing this with one and the same sample is laborious at best, due to deformation and biodegradation during measurements or intermediary preparation steps. Furthermore, data alignment using differing imaging techniques turns out to be a complex task, which considerably complicates the interconnection of results. We present correlative imaging of the accessory rat lung lobe by combining a modified Scanning Laser Optical Tomography (SLOT) setup with a specially developed sample preparation method (CRISTAL). CRISTAL is a resin-based embedding method that optically clears the specimen while allowing sectioning and preventing degradation. We applied and correlated SLOT with Multi Photon Microscopy, histological and immunofluorescence analysis as well as Transmission Electron Microscopy, all in the same sample. Thus, combining CRISTAL with SLOT enables the correlative utilization of a vast variety of imaging techniques.

  15. Set-up and calibration of a method to measure 10B concentration in biological samples by neutron autoradiography

    Science.gov (United States)

    Gadan, M. A.; Bortolussi, S.; Postuma, I.; Ballarini, F.; Bruschi, P.; Protti, N.; Santoro, D.; Stella, S.; Cansolino, L.; Clerici, A.; Ferrari, C.; Zonta, A.; Zonta, C.; Altieri, S.

    2012-03-01

    A selective uptake of boron in the tumor is the base of Boron Neutron Capture Therapy, which can destroy the tumor substantially sparing the normal tissue. In order to deliver a lethal dose to the tumor, keeping the dose absorbed by normal tissues below the tolerance level, it is mandatory to know the 10B concentration present in each kind of tissue at the moment of irradiation. This work presents the calibration procedure adopted for a boron concentration measurement method based on neutron autoradiography, where biological samples are deposited on sensitive films and irradiated in the thermal column of the TRIGA reactor (University of Pavia). The latent tracks produced in the film by the charged particles coming from the neutron capture in 10B are made visible by a proper etching, allowing the measurement of the track density. A calibration procedure with standard samples provides curves of track density as a function of boron concentration, to be used in the measurement of biological samples. In this paper, the bulk etch rate parameter and the calibration curves obtained for both liquid samples and biological tissues with known boron concentration are presented. A bulk etch rate value of (1.64 ± 0.02) μm/h and a linear dependence with etching time were found. The plots representing the track density versus the boron concentration in a range between 5 and 50 μg/g (ppm) are linear, with an angular coefficient of (1.614 ± 0.169)·10-3 tracks/(μm2 ppm) for liquids and (1.598 ± 0.097)·10-2 tracks/(μm2 ppm) for tissues.

  16. Mouse xenograft modeling of human adult acute lymphoblastic leukemia provides mechanistic insights into adult LIC biology

    Science.gov (United States)

    Dey, Aditi; Castleton, Anna Z.; Schwab, Claire; Samuel, Edward; Sivakumaran, Janani; Beaton, Brendan; Zareian, Nahid; Zhang, Christie Yu; Rai, Lena; Enver, Tariq; Moorman, Anthony V.; Fielding, Adele K.

    2014-01-01

    The distinct nature of acute lymphoblastic leukemia (ALL) in adults, evidenced by inferior treatment outcome and different genetic landscape, mandates specific studies of disease-initiating mechanisms. In this study, we used NOD/LtSz-scid IL2Rγ nullc (NSG) mouse xenotransplantation approaches to elucidate leukemia-initiating cell (LIC) biology in primary adult precursor B (pre-B) ALL to optimize disease modeling. In contrast with xenografting studies of pediatric ALL, we found that modification of the NSG host environment using preconditioning total body irradiation (TBI) was indispensable for efficient engraftment of adult non-t(4;11) pre-B ALL, whereas t(4;11) pre-B ALL was successfully reconstituted without this adaptation. Furthermore, TBI-based xenotransplantation of non-t(4;11) pre-B ALL enabled detection of a high frequency of LICs (<1:6900) and permitted frank leukemic engraftment from a remission sample containing drug-resistant minimal residual disease. Investigation of TBI-sensitive stromal-derived factor-1/chemokine receptor type 4 signaling revealed greater functional dependence of non-t(4;11) pre-B ALL on this niche-based interaction, providing a possible basis for the differential engraftment behavior. Thus, our studies establish the optimal conditions for experimental modeling of human adult pre-B ALL and demonstrate the critical protumorogenic role of microenvironment-derived SDF-1 in regulating adult pre-B LIC activity that may present a therapeutic opportunity. PMID:24825861

  17. Phase microscopy of technical and biological samples through random phase modulation with a difuser

    DEFF Research Database (Denmark)

    Almoro, Percival; Pedrini, Giancarlo; Gundu, Phanindra Narayan

    2010-01-01

    A technique for phase microscopy using a phase diffuser and a reconstruction algorithm is proposed. A magnified specimen wavefront is projected on the diffuser plane that modulates the wavefront into a speckle field. The speckle patterns at axially displaced planes are sampled and used in an iter...

  18. Detection of mutant protein in complex biological samples: Glucocerebrosidase mutations in Gaucher’s disease

    NARCIS (Netherlands)

    Bleijlevens, B.; van Breemen, M.J.; Donker-Koopman, W.E.; de Koster, C.G.; Aerts, J.M.F.G.

    2008-01-01

    We report a sensitive method to detect point mutations in proteins from complex samples. The method is based on surface-enhanced laser desorption/ionization time-of-flight (SELDI-ToF) MS but can be extended to other MS platforms. The target protein in this study is the lysosomal enzyme glucocerebros

  19. Determination of total magnesium in biological samples using electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Hulanicki, Adam; Godlewska, Beata; Brzóska, Malgorzata

    1995-11-01

    Magnesium content is an important diagnostic parameter in medicine. It is recognized that its determination in one compartment is not sufficient for reliable information about the magnesium status in the body. In addition to the common procedures of magnesium determination in blood by flame atomic absorption spectrometry, the procedure of electrothermal atomization has also been developed and applied to the analysis of blood fractions, mononuclear cells and isolated nuclei of liver cells. Electrothermal atomization is preferred in cases where the sample size is limited and the magnesium content low. The total errors are in the order of 3-4%. Various techniques of sample pretreatment have been tested and direct dilution with 0.05 mol l -1 nitric acid was optimal when the samples were not mineralized. The calibration graph based on standards containing albumin was found to give the best results, as the form of magnesium in the samples may influence the ashing and atomization processes. Good agreement was obtained for determination of magnesium in standard serum. The results are compared with those obtained by the standard flame atomization technique.

  20. Sample Preparation and Identification of Biological, Chemical and Mid-Spectrum Agents

    Science.gov (United States)

    2005-10-01

    substrate molecule is called a hydrolase. Substrates commonly used are sodium hippurate, DNA, urea, esculin, starch , casein, lecithin and polysorbate-80...processed sample are first denatured and separated by gel electrophoresis [usually sodium dodecyl polyacrylamide gel electrophoresis (SDS-PAGE)] and

  1. Solid-phase extraction and liquid chromatographic quantitation of quinfamide in biological samples.

    Science.gov (United States)

    Morales, J M; Jung, C H; Alarcón, A; Barreda, A

    2000-09-15

    This paper describes a high-performance liquid chromatographic method for the assay of quinfamide and its main metabolite, 1-(dichloroacetyl)-1,2,3,4,-tetrahydro-6-quinolinol, in plasma, urine and feces. It requires 1 ml of biological fluid, an extraction using Sep-Pack cartridges and acetonitrile for drug elution. Analysis was performed on a CN column (5 microm) using water-acetonitrile-methanol (40:50:10) as a mobile phase at 269 nm. Results showed that the assay was linear in the range between 0.08 and 2.0 microg/ml. The limit of quantitation was 0.08 microg/ml. Maximum assay coefficient of variation was 14%. Recovery obtained in plasma, urine and feces ranged from 82% to 98%.

  2. Contrastive analysis of hedges in a sample of Chinese and English molecular biology papers.

    Science.gov (United States)

    Gao, Xiaofang

    2004-10-01

    Hedge is defined as the expression of provisionalness and possibility that makes scientific messages tentative, vague, and imprecise, thereby reducing the force of claims scientists make. Linguistic study of hedges began in the early 1970s in generative semantics. Since then, the focus has shifted from seeking linguistic properties in spoken discourse to analyzing its pragmatic functions in written contextual communication. The purpose of this paper was to analyze hedges in Chinese and English scientific articles from the perspective of contrastive pragmatics. Based on a contextual analysis of 5 Chinese and 5 English scientific articles, selected randomly, from two journals in molecular biology--Science in China and Proceedings of the National Academy of Sciences of the United States of America, there were significant differences between Chinese and English scientific articles in use of hedges.

  3. Human DNA quantification and sample quality assessment: Developmental validation of the PowerQuant(®) system.

    Science.gov (United States)

    Ewing, Margaret M; Thompson, Jonelle M; McLaren, Robert S; Purpero, Vincent M; Thomas, Kelli J; Dobrowski, Patricia A; DeGroot, Gretchen A; Romsos, Erica L; Storts, Douglas R

    2016-07-01

    Quantification of the total amount of human DNA isolated from a forensic evidence item is crucial for DNA normalization prior to short tandem repeat (STR) DNA analysis and a federal quality assurance standard requirement. Previous commercial quantification methods determine the total human DNA and total human male DNA concentrations, but provide limited information about the condition of the DNA sample. The PowerQuant(®) System includes targets for quantification of total human and total human male DNA as well as targets for evaluating whether the human DNA is degraded and/or PCR inhibitors are present in the sample. A developmental validation of the PowerQuant(®) System was completed, following SWGDAM Validation Guidelines, to evaluate the assay's specificity, sensitivity, precision and accuracy, as well as the ability to detect degraded DNA or PCR inhibitors. In addition to the total human DNA and total human male DNA concentrations in a sample, data from the degradation target and internal PCR control (IPC) provide a forensic DNA analyst meaningful information about the quality of the isolated human DNA and the presence of PCR inhibitors in the sample that can be used to determine the most effective workflow and assist downstream interpretation.

  4. Human evolution, life history theory, and the end of biological reproduction.

    Science.gov (United States)

    Last, Cadell

    2014-01-01

    Throughout primate history there have been three major life history transitions towards increasingly delayed sexual maturation and biological reproduction, as well as towards extended life expectancy. Monkeys reproduce later and live longer than do prosimians, apes reproduce later and live longer than do monkeys, and humans reproduce later and live longer than do apes. These life history transitions are connected to increased encephalization. During the last life history transition from apes to humans, increased encephalization co-evolved with increased dependence on cultural knowledge for energy acquisition. This led to a dramatic pressure for more energy investment in growth over current biological reproduction. Since the industrial revolution socioeconomic development has led to even more energy being devoted to growth over current biological reproduction. I propose that this is the beginning of an ongoing fourth major primate life history transition towards completely delayed biological reproduction and an extension of the evolved human life expectancy. I argue that the only fundamental difference between this primate life history transition and previous life history transitions is that this transition is being driven solely by cultural evolution, which may suggest some deeper evolutionary transition away from biological evolution is already in the process of occurring.

  5. Kant on epigenesis, monogenesis and human nature: the biological premises of anthropology.

    Science.gov (United States)

    Cohen, Alix A

    2006-12-01

    The aim of this paper is to show that for Kant, a combination of epigenesis and monogenesis is the condition of possibility of anthropology as he conceives of it and that moreover, this has crucial implications for the biological dimension of his account of human nature. More precisely, I begin by arguing that Kant's conception of mankind as a natural species is based on two premises: firstly the biological unity of the human species (monogenesis of the human races); and secondly the existence of 'seeds' which may or may not develop depending on the environment (epigenesis of human natural predispositions). I then turn to Kant's account of man's natural predispositions and show that far from being limited to the issue of races, it encompasses unexpected human features such as gender, temperaments and nations. These predispositions, I argue, are means to the realisation of Nature's overall purpose for the human species. This allows me to conclude that man's biological determinism leads to the species' preservation, cultivation and civilisation.

  6. A comparison of sample preparation strategies for biological tissues and subsequent trace element analysis using LA-ICP-MS.

    Science.gov (United States)

    Bonta, Maximilian; Török, Szilvia; Hegedus, Balazs; Döme, Balazs; Limbeck, Andreas

    2017-03-01

    Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is one of the most commonly applied methods for lateral trace element distribution analysis in medical studies. Many improvements of the technique regarding quantification and achievable lateral resolution have been achieved in the last years. Nevertheless, sample preparation is also of major importance and the optimal sample preparation strategy still has not been defined. While conventional histology knows a number of sample pre-treatment strategies, little is known about the effect of these approaches on the lateral distributions of elements and/or their quantities in tissues. The technique of formalin fixation and paraffin embedding (FFPE) has emerged as the gold standard in tissue preparation. However, the potential use for elemental distribution studies is questionable due to a large number of sample preparation steps. In this work, LA-ICP-MS was used to examine the applicability of the FFPE sample preparation approach for elemental distribution studies. Qualitative elemental distributions as well as quantitative concentrations in cryo-cut tissues as well as FFPE samples were compared. Results showed that some metals (especially Na and K) are severely affected by the FFPE process, whereas others (e.g., Mn, Ni) are less influenced. Based on these results, a general recommendation can be given: FFPE samples are completely unsuitable for the analysis of alkaline metals. When analyzing transition metals, FFPE samples can give comparable results to snap-frozen tissues. Graphical abstract Sample preparation strategies for biological tissues are compared with regard to the elemental distributions and average trace element concentrations.

  7. A rapid method for assaying thiaminase I activity in diverse biological samples.

    Directory of Open Access Journals (Sweden)

    Clifford E Kraft

    Full Text Available Vitamin B1 (thiamine deficiencies can lead to neurological disorders, reproductive failure and death in wild and domestic animal populations. In some cases, disease is brought about by the consumption of foods high in thiaminase I activity. Levels of thiaminase activity in these foods are highly variable and the factors leading to production of this enzyme are poorly understood. Here we describe improvements in a spectrophotometric thiaminase I activity assay that measures the disappearance of 4-nitrothiophenol, a favored nucleophile co-substrate that replaces the thiazole portion of thiamine during the inactivation of thiamine by the enzyme. Scalable sample processing protocols and a 96-well microtiter plate format are presented that allow the rapid evaluation of multiple, replicated samples in the course of only a few hours. Observed levels of activity in bacterial culture supernatant, fish, ferns and molluscs using this colorimetric assay were similar to previously published reports that employed a radiometric method. Organisms devoid of thiaminase I, based upon previous work, showed no activity with this assay. In addition, activity was found in a variety of fishes and one fern species from which this enzyme had not previously been reported. Overall, we demonstrate the suitability of this technique for measuring thiaminase I activity within small amounts of tissue and environmental samples with replication levels that were heretofore prohibitive. The assay provides a considerable improvement in the ability to examine and understand the properties of an enzyme that has a substantial influence on organism and ecosystem health.

  8. Label-free quantification of Tacrolimus in biological samples by atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Menotta, Michele, E-mail: michele.menotta@uniurb.it [Department of Biomolecular Sciences, University of Urbino “Carlo Bo” via Saffi 2, Urbino (Italy); Biagiotti, Sara [Department of Biomolecular Sciences, University of Urbino “Carlo Bo” via Saffi 2, Urbino (Italy); Streppa, Laura [Physics Laboratory, CNRS-ENS, UMR 5672, Lyon (France); Cell and Molecular Biology Laboratory, CNRS-ENS Lyon, UMR 5239, IFR128, Lyon (France); Rossi, Luigia; Magnani, Mauro [Department of Biomolecular Sciences, University of Urbino “Carlo Bo” via Saffi 2, Urbino (Italy)

    2015-07-16

    Highlights: • Tacrolimus is a potent immunosuppressant drug that has to be continually monitored. • We present an atomic force microscope approach for quantification of Tacrolimus in blood samples. • Detection and quantification have been successfully achieved. - Abstract: In the present paper we describe an atomic force microscopy (AFM)-based method for the quantitative analysis of FK506 (Tacrolimus) in whole blood (WB) samples. Current reference methods used to quantify this immunosuppressive drug are based on mass spectrometry. In addition, an immunoenzymatic assay (ELISA) has been developed and is widely used in clinic, even though it shows a small but consistent overestimation of the actual drug concentration when compared with the mass spectrometry method. The AFM biosensor presented herein utilises the endogen drug receptor, FKBP12, to quantify Tacrolimus levels. The biosensor was first assayed to detect the free drug in solution, and subsequently used for the detection of Tacrolimus in blood samples. The sensor was suitable to generate a dose–response curve in the full range of clinical drug monitoring. A comparison with the clinically tested ELISA assay is also reported.

  9. HPD: an online integrated human pathway database enabling systems biology studies.

    Science.gov (United States)

    Chowbina, Sudhir R; Wu, Xiaogang; Zhang, Fan; Li, Peter M; Pandey, Ragini; Kasamsetty, Harini N; Chen, Jake Y

    2009-10-08

    Pathway-oriented experimental and computational studies have led to a significant accumulation of biological knowledge concerning three major types of biological pathway events: molecular signaling events, gene regulation events, and metabolic reaction events. A pathway consists of a series of molecular pathway events that link molecular entities such as proteins, genes, and metabolites. There are approximately 300 biological pathway resources as of April 2009 according to the Pathguide database; however, these pathway databases generally have poor coverage or poor quality, and are difficult to integrate, due to syntactic-level and semantic-level data incompatibilities. We developed the Human Pathway Database (HPD) by integrating heterogeneous human pathway data that are either curated at the NCI Pathway Interaction Database (PID), Reactome, BioCarta, KEGG or indexed from the Protein Lounge Web sites. Integration of pathway data at syntactic, semantic, and schematic levels was based on a unified pathway data model and data warehousing-based integration techniques. HPD provides a comprehensive online view that connects human proteins, genes, RNA transcripts, enzymes, signaling events, metabolic reaction events, and gene regulatory events. At the time of this writing HPD includes 999 human pathways and more than 59,341 human molecular entities. The HPD software provides both a user-friendly Web interface for online use and a robust relational database backend for advanced pathway querying. This pathway tool enables users to 1) search for human pathways from different resources by simply entering genes/proteins involved in pathways or words appearing in pathway names, 2) analyze pathway-protein association, 3) study pathway-pathway similarity, and 4) build integrated pathway networks. We demonstrated the usage and characteristics of the new HPD through three breast cancer case studies. HPD http://bio.informatics.iupui.edu/HPD is a new resource for searching, managing

  10. Critical values of the external magnetic field leading biological effects in the human organism

    CERN Document Server

    Kanokov, Zakirjon

    2013-01-01

    In the framework of the simplified stochastic model the critical values of an induction of the external magnetic field leading to sharp increase of fluctuations of a casual current of biologically important ions in different blood vessels of a human body are calculated.

  11. 78 FR 32668 - Draft Guidance for Industry: Changes to an Approved Application: Biological Products: Human Blood...

    Science.gov (United States)

    2013-05-31

    ...The Food and Drug Administration (FDA) is announcing the availability of a draft document entitled ``Guidance for Industry: Changes to an Approved Application: Biological Products: Human Blood and Blood Components Intended for Transfusion or for Further Manufacture'' dated June 2013. The draft guidance document provides manufacturers of licensed Whole Blood and blood components intended for......

  12. Nutrition and the biology of human ageing: Proceedings of the ninth nestle international nutrition symposium

    Science.gov (United States)

    This 9th Nestle Nutrition Symposium on “Nutrition and the Biology of Human Ageing” is presented at a time of unprecedented demographic change worldwide. The UN population division forecasts that the number of people living over age 65 will rise to almost 1 billion (12% percent of the world’s populat...

  13. The Use of Ethical Frameworks for Implementing Science as a Human Endeavour in Year 10 Biology

    Science.gov (United States)

    Yap, Siew Fong; Dawson, Vaille

    2014-01-01

    This research focuses on the use of ethical frameworks as a pedagogical model for socio-scientific education in implementing the "Science as a Human Endeavour" (SHE) strand of the Australian Curriculum: Science in a Year 10 biology class in a Christian college in metropolitan Perth, Western Australia. Using a case study approach, a mixed…

  14. Human biological monitoring for exposure assessment in response to an incident involving hazardous materials

    NARCIS (Netherlands)

    Scheepers, P.T.J.; Brederode, N.E. van; Bos, P.M.J.; Nijhuis, N.J.; Weerdt, R.H. van de; Woude, I. van der; Eggens, M.L.

    2014-01-01

    Biological monitoring in humans (HBM) is widely used in the field of occupational and environmental health. In the situation of an unexpected release of hazardous materials HBM may contribute to the medical support and treatment of exposed individuals from the general population or of emergency

  15. Biohorizons: An eConference to Assess Human Biology in Large, First-Year Classes

    Science.gov (United States)

    Moni, Roger W.; Moni, Karen B.; Poronnik, Philip; Lluka, Lesley J.

    2007-01-01

    The authors detail the design, implementation and evaluation of an eConference entitled "Biohorizons," using a presage-process-product model to describe the development of an eLearning community. Biohorizons was a summative learning and assessment task aiming to introduce large classes of first-year Human Biology students to the practices of…

  16. Evaluation of an ultrasonic acid digestion procedure for total heavy metals determination in environmental and biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Kazi, Tasneem G. [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: tgkazi@yahoo.com; Jamali, Mohammad K. [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: mkhanjamali@yahoo.com; Arain, Mohammad B. [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: bilal_ku2004@yahoo.com; Afridi, Hassan I. [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: hassanimranafridi@yahoo.com; Jalbani, Nusrat [Pakistan Council for Scientific and Industrial Research, University Road, Karachi 75280 (Pakistan)], E-mail: nusratjalbani_21@yahoo.com; Sarfraz, Raja A. [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: rajaadilsarfraz@gmail.com; Ansari, Rehana [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)], E-mail: rehana_ansari_57@yahoo.com

    2009-01-30

    In this study, a sample preparation method based on ultrasonic assisted acid digestion (UAD) has been evaluated for total heavy metals (Cd, Cr, Ni and Pb) determination in different environmental (soil, sediment and sewage sludge), and biological (fish muscles, vegetables and grains) samples, using electrothermal atomic absorption spectrometry (ETAAS). The investigated parameters influencing UAD such as presonication time, sonication time, temperature of ultrasonic bath, and different acid mixtures were fully optimized, whereas power was maintained constant at 100% of nominal power of ultrasonic bath. Six different sets of above parameters were applied on six certified reference materials (CRMs) having different matrices. The accuracy of the method was also tested by comparing the results with those obtained from conventional hot plate assisted acid digestion method on same CRMs. Analytical results for HMs by both methods showed no significant difference at 95% confidence limit (p < 0.05). Recoveries of HMs ranging from 96.2% to 102% and 96.3% to 98.6% were obtained from biological and environmental samples, respectively. The average relative standard deviation of UAD method varied between 3.5% and 8.2%, depending on the analyte.

  17. A signature-based method to distinguish time-of-flight secondary-ion mass spectra from biological samples.

    Science.gov (United States)

    Quong, Judy N; Quong, Andrew A; Wu, Kuang Jen; Kercher, James R

    2005-11-01

    Time-Of-Flight Mass Spectrometry (TOF-SIMS) was used to determine elemental and biomolecular ions from isolated protein samples. We identified a set of 23 mass-to-charge ratio (m/z) peaks that represent signatures for distinguishing biological samples. The 23 peaks were identified by Singular Value Decomposition (SVD) and Canonical Analysis (CA) to find the underlying structure in the complex mass-spectra data sets. From this modified data, SVD was used to identify sets of m/z peaks, and we used these patterns from the TOF-SIMS data to predict the biological source from which individual mass spectra were generated. The signatures were validated using an additional data set different from the initial training set used to identify the signatures. We present a simple method to identify multiple variables required for sample classification based on mass spectra that avoids overfit. This is important in a variety of studies using mass spectrometry, including the ability to identify proteins in complex mixtures and for the identification of new biomarkers.

  18. Determination of lead in biological samples of children with different physiological consequences using cloud point extraction method.

    Science.gov (United States)

    Shah, Faheem; Kazi, Tasneem Gul; Ullah, Naeem; Afridi, Hassan Imran

    2013-06-01

    In present study, lead (Pb) level in biological samples of children with physiological disorders (liver, bone, and gastrointestinal; age ranged 1-10 years) have been assessed. For comparison purpose, age-matched healthy children were also selected. Cloud point extraction (CPE) was employed for preconcentration of Pb in acid-digested biological samples prior to its determination by flame atomic absorption spectrometry (FAAS). Dithizone (diphenylthiocarbazone) and nonionic surfactant Triton X-114 (TX-114) were used as complexing reagent and extractant, respectively. The effects of several experimental variables on proposed CPE were evaluated. Under the optimum experimental conditions, the observed detection limit (LOD) and the enhancement factor (EF) were 0.08 μg L(-1) and 53, respectively. Relative standard deviation (RSD) of 10 μg L(-1) Pb was 3.4 %. It was observed that children with liver-, bone-, and gastrointestinal-related disorders had three- to fourfold higher Pb level in blood and scalp hair samples.

  19. Correlation of Arsenic Levels in Smokeless Tobacco Products and Biological Samples of Oral Cancer Patients and Control Consumers.

    Science.gov (United States)

    Arain, Sadaf S; Kazi, Tasneem G; Afridi, Hassan I; Talpur, Farah N; Kazi, Atif G; Brahman, Kapil D; Naeemullah; Panhwar, Abdul H; Kamboh, Muhammad A

    2015-12-01

    It has been extensively reported that chewing of smokeless tobacco (SLT) can lead to cancers of oral cavity. In present study, the relationship between arsenic (As) exposure via chewing/inhaling different SLT products in oral cancer patients have or/not consumed SLT products was studied. The As in different types of SLT products (gutkha, mainpuri, and snuff) and biological (scalp hair and blood) samples of different types of oral cancer patients and controls were analyzed. Both controls and oral cancer patients have same age group (ranged 30-60 years), socio-economic status, localities, and dietary habits. The concentrations of As in SLT products and biological samples were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials. The resulted data of present study indicates that the concentration of As was significantly higher in scalp hair and blood samples of oral cancer patients than those of controls (p0.01). The intake of As via consuming different SLT may have synergistic effects, in addition to other risk factors associated with oral cancer.

  20. How do precision medicine and system biology response to human body's complex adaptability?

    Science.gov (United States)

    Yuan, Bing

    2016-12-01

    In the field of life sciences, although system biology and "precision medicine" introduce some complex scientifific methods and techniques, it is still based on the "analysis-reconstruction" of reductionist theory as a whole. Adaptability of complex system increase system behaviour uncertainty as well as the difficulties of precise identifification and control. It also put systems biology research into trouble. To grasp the behaviour and characteristics of organism fundamentally, systems biology has to abandon the "analysis-reconstruction" concept. In accordance with the guidelines of complexity science, systems biology should build organism model from holistic level, just like the Chinese medicine did in dealing with human body and disease. When we study the living body from the holistic level, we will fifind the adaptability of complex system is not the obstacle that increases the diffificulty of problem solving. It is the "exceptional", "right-hand man" that helping us to deal with the complexity of life more effectively.