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1.
Chmelík J  Mazanec K  Slais K 《Electrophoresis》2007,28(18):3315-3323
A new proteomic staining-free method for simultaneous identification of proteins and determination of their pI values by using low-molecular-mass pI markers is described. It is based on separation of proteins in gels by IEF in combination with mass spectrometric analysis of both peptides derived by in-gel digestion and low-molecular-mass pI markers extracted form the same piece excised from the gel. In this method, the pI markers are mixed with a protein mixture (a commercial malted barley protein extract) deposited on a gel and separated in a pH gradient. Color pI markers enable supervision of progress of focusing process. Several separated bands of the pI markers (including separated proteins) were excised and the pI markers were eluted from each gel piece by water/ethanol and identified by MALDI-TOF/TOF MS. The remaining carrier ampholytes were then washed out from gel pieces and proteins were in-gel digested with trypsin or chymotrypsin. Obtained peptides were measured by MALDI-TOF/TOF MS and proteins were identified via protein database search. This procedure allows omitting time-consuming protein staining and destaining procedures, which shortens the analysis time. For comparison, other IEF gels were stained with CBB R 250 and proteins in the gel bands were identified. Similarity of the results confirmed that our approach can give information about the correct pI values of particular proteins in complex samples at significantly shorter analysis times. This method can be very useful for identification of proteins and their post-translational modifications in prefractioned samples, where post-translational modifications (e.g., glycation) are frequent.  相似文献   

2.
The analysis of controlled drugs in forensic matrices, i.e., urine, blood, plasma, saliva, and hair, is one of the current hot topics in the clinical and toxicological context. The use of microextraction-based approaches has gained considerable notoriety, mainly due to the great simplicity, cost-benefit, and environmental sustainability. For this reason, the application of these innovative techniques has become more relevant than ever in programs for monitoring priority substances such as the main illicit drugs, e.g., opioids, stimulants, cannabinoids, hallucinogens, dissociative drugs, and related compounds. The present contribution aims to make a comprehensive review on the state-of-the art advantages and future trends on the application of microextraction-based techniques for screening-controlled drugs in the forensic context.  相似文献   

3.
Forensic applications of ambient ionization mass spectrometry   总被引:1,自引:0,他引:1  
This review highlights and critically assesses forensic applications in the developing field of ambient ionization mass spectrometry. Ambient ionization methods permit the ionization of samples outside the mass spectrometer in the ordinary atmosphere, with minimal sample preparation. Several ambient ionization methods have been created since 2004 and they utilize different mechanisms to create ions for mass-spectrometric analysis. Forensic applications of these techniques—to the analysis of toxic industrial compounds, chemical warfare agents, illicit drugs and formulations, explosives, foodstuff, inks, fingerprints, and skin—are reviewed. The minimal sample pretreatment needed is illustrated with examples of analysis from complex matrices (e.g., food) on various substrates (e.g., paper). The low limits of detection achieved by most of the ambient ionization methods for compounds of forensic interest readily offer qualitative confirmation of chemical identity; in some cases quantitative data are also available. The forensic applications of ambient ionization methods are a growing research field and there are still many types of applications which remain to be explored, particularly those involving on-site analysis. Aspects of ambient ionization currently undergoing rapid development include molecular imaging and increased detection specificity through simultaneous chemical reaction and ionization by addition of appropriate chemical reagents.  相似文献   

4.
An overview is given of the existing standards and guidelines for analytical toxicology. Details about guidelines concerning forensic toxicology, clinical toxicology, point-of-care testing, and an area of overlap are provided. Guidelines and standards exist for forensic toxicological analysis in general and for specific situations, e.g., workplace drug testing and driving under the influence of drugs and alcohol. For workplace drug testing, detailed guidelines exist in the U.S.A., Australia, and Europe describing for example the methods used, their cut-off and the process of sample handling. Some governments describe the methods and quality requirements for blood alcohol testing for driving under the influence of alcohol in detail in their laws. In the area of clinical toxicology, guidelines not only focus on the analytical aspects of analysis but also on the timeliness of results. According to the US- and UK-based practice guidelines for the emergency department, the turn-around time should be 1 or 2 h, respectively, for a specific set of analytes. Guidelines are either being developed now or already available (e.g., workplace drug testing, breath alcohol analysis) for point-of-care testing in analytical toxicology. In the context of brain death and sexual assault cases, specific demands need to be imposed because of the unique aspects of drug analysis in these situations (variety of drugs used, low concentrations). Many guidelines and standards are available and it is up to every laboratory to choose the best ones depending on the area of activity and the legal and regulatory environment.Presented at the 10th Conference Quality in the Spotlight, March 2005, Antwerp, Belgium  相似文献   

5.
In the clinical laboratory, one of the most objective ways to perform the final review of patients’ measured values is the use of computerized plausibility control (i.e., set of procedures used to decide whether a patient’s measured value is valid according to established clinical and biological criteria). This study is focused on the estimation of alert and change limits to be applied to detect doubtful patients’ measured values. These limits are useful to improve the final review of patients’ measured values since these limits are produced objectively and are selected according to the clinical laboratory needs, letting the clinical laboratory professional staff to save time and effort.  相似文献   

6.
In the last decade, liquid chromatography coupled to (tandem) mass spectrometry (LC-MS(-MS)) has become a versatile technique with many routine applications in clinical and forensic toxicology. However, it is well-known that ionization in LC-MS(-MS) is prone to so-called matrix effects, i.e., alteration in response due to the presence of co-eluting compounds that may increase (ion enhancement) or reduce (ion suppression) ionization of the analyte. Since the first reports on such matrix effects, numerous papers have been published on this matter and the subject has been reviewed several times. However, none of the existing reviews has specifically addressed aspects of matrix effects of particular interest and relevance to clinical and forensic toxicology, for example matrix effects in methods for multi-analyte or systematic toxicological analysis or matrix effects in (alternative) matrices almost exclusively analyzed in clinical and forensic toxicology, for example meconium, hair, oral fluid, or decomposed samples in postmortem toxicology. This review article will therefore focus on these issues, critically discussing experiments and results of matrix effects in LC-MS(-MS) applications in clinical and forensic toxicology. Moreover, it provides guidance on performance of studies on matrix effects in LC-MS(-MS) procedures in systematic toxicological analysis and postmortem toxicology.  相似文献   

7.
Patients with advanced prostate cancer can develop painful and debilitating bone metastases. Currently available interventions for prostate cancer bone metastases, including chemotherapy, bisphosphonates, and radiopharmaceuticals, are only palliative. They can relieve pain, reduce complications (e.g., bone fractures), and improve quality of life, but they do not significantly improve survival times. Therefore, additional strategies to enhance the diagnosis and treatment of prostate cancer bone metastases are needed. Nanotechnology is a versatile platform that has been used to increase the specificity and therapeutic efficacy of various treatments for prostate cancer bone metastases. In this review, we summarize preclinical research that utilizes nanotechnology to develop novel diagnostic imaging tools, translational models, and therapies to combat prostate cancer bone metastases.  相似文献   

8.
Bone metastasis remains a major cause of death in cancer patients, and current therapies for bone metastatic disease are mainly palliative. Bone metastases arise after cancer cells have colonized the bone and co-opted the normal bone remodeling process. In addition to bone-targeted therapies (e.g., bisphosphonate and denosumab), hormone therapy, chemotherapy, external beam radiation therapy, and surgical intervention, attempts have been made to use systemic radiotherapy as a means of delivering cytocidal radiation to every bone metastatic lesion. Initially, several bone-seeking beta-minus-particle-emitting radiopharmaceuticals were incorporated into the treatment for bone metastases, but they failed to extend the overall survival in patients. However, recent clinical trials indicate that radium-223 dichloride (223RaCl2), an alpha-particle-emitting radiopharmaceutical, improves the overall survival of prostate cancer patients with bone metastases. This success has renewed interest in targeted alpha-particle therapy development for visceral and bone metastasis. This review will discuss (i) the biology of bone metastasis, especially focusing on the vicious cycle of bone metastasis, (ii) how bone remodeling has been exploited to administer systemic radiotherapies, and (iii) targeted radiotherapy development and progress in the development of targeted alpha-particle therapy for the treatment of prostate cancer bone metastasis.  相似文献   

9.
This review deals with the emerging field of fluorescent conjugated polymers for the development of chemical and/or biochemical sensors. As a result of their amplified physical properties due to a “molecular wire effect”, these materials offer excellent characteristics to develop different sensing schemes (e.g., employing direct superquenching or relying on development of fluorescence-resonance-energy-transfer formats). The versatility of their synthesis procedures allows us to introduce the desired functional groups to achieve analytically useful interactions with analytes [e.g., from transition-metal ions to explosives, or even, in recent years, relevant biomolecules (e.g., proteins or DNA, where conformational changes play a decisive role in detection)].  相似文献   

10.
Amyotrophic lateral sclerosis, or Lou Gehrig's disease, is characterized by motor neuron death, with average survival times of two to five years. One cause of this disease is the misfolding of superoxide dismutase 1 (SOD1), a phenomenon influenced by point mutations spanning the protein. Herein, we used an epitope‐specific high‐throughput screen to identify a peptide ligand that stabilizes the SOD1 native conformation and accelerates its folding by a factor of 2.5. This strategy may be useful for fundamental studies of protein energy landscapes as well as designing new classes of therapeutics.  相似文献   

11.
Detection of a drug and its glucuronide metabolite(s) is of great importance in interpretive forensic and clinical toxicology. Until recently, glucuronides were determined by cleavage of the glucuronide with an enzyme (e.g., β-glucuronidase) to yield the parent compound, which was subsequently detected, or via derivatization to a more volatile or detectable analogue. Direct detection of the glucuronide conjugates overcomes the critical limitations of approaches that involve enzymatic cleavage procedures and/or derivatization. This review will focus on direct methods to determine glucuronides of various potentially abused drugs in human biological matrices. More specifically, this review will be restricted to methods that involve liquid chromatography (LC) coupled with various detectors. Papers are presented in chronological order for each compound class to emphasize the evolution of methodology and continued importance of the application.  相似文献   

12.
《Analytical letters》2012,45(3):436-445
The usefulness of VIS microspectrometry for comparison of very small car paint traces was studied. Eighteen samples of solid and metallic paints taken from new and repainted cars were examined. Each sample was measured in both transmittance and reflectance mode (on top surface and on cross-section). Using the CIELAB units the repeatability of the color measurement was assessed. A criterion allowing two parts of the same sample and two samples of the same color to be distinguished was established. The method was proved to be an useful instrumental tool–complementary to other analytical methods (e.g., IR spectrometry)–in examination of car paint traces for forensic purposes.  相似文献   

13.
Work in bioelectromagnetics has long been plagued by problems with replication. This includes experiments done on electromagnetic (EM) field-induced effects in chick embryos. Our laboratory investigated responses of embryos from two flocks of White Leghorn hens. Both flocks were studied simultaneously, and it was found that they responded differently to EM field exposures. Embryos were exposed to 60 Hz, 8 microT EM fields prior to placement in an anoxic chamber. Following re-oxygenation, survival in controls was 34.6%, exposed flock 1 survival was 62% (P < 0.0001) and exposed flock 2 survival was 43% (P < 0.0136). P values are from comparison of data between EM field exposed embryos (flocks 1 and 2) versus controls. In order to induce maximum protection in flock 2, (approximately 62% survival), embryos required a longer exposure time at higher magnetic field strengths. These results reinforce the concepts that genetics are important in determining whether or not chick embryos will respond to EM field stimulation. A broader look at the role of genetic factors emphasizes that these variations in response to external stimuli (e.g., drugs, radiation, and EM fields) are found in all areas of biological research (cell culture, chick, rat, and human studies). The present study suggests that genetics may be a prime cause of the difficulties encountered in replication studies in the field of bioelectromagnetics. We conclude that replication studies should not be undertaken unless care is taken to insure that exactly the same strains of cells or animals are used. Researchers should also first confirm that the responses of their model to non-EM field stimuli are similar to that obtained in the original study.  相似文献   

14.
Obesity is a foremost health issue that affects about 1.6 million people out of which 400 million worldwide. Epidemiological evidences prove obesity is the primary cause for various metabolic ailments e.g. diabetes. Poria cocos possess extensive biological actions, for instance, antioxidant, anti-inflammatory, antitumor, immunomodulatory actions. The primary limitation of all phytomedicine was their poor bioavailability hence in this investigation, we bio-fabricated the gold nanoparticles from Poria cocos aqueous extract and inspected their potency to treat obesity. Obese rat model were produced via fed the young female rats with high fat food for 8 weeks regimen. Further to confirm the potency of Poria cocos gold nanoparticles against obesity induced metabolic disorders we treated obese rats with low dose streptozotocin in the conclusion of the investigational time. The synthesis of Poria cocos gold-nanoparticles was evidenced via the UV-Spectroscopic study and characterized with SEM, TEM and EDAX studies. The anti-obesity actions of Poria cocos gold-nanoparticles were investigated by estimating the glucose profile, kidney markers, lipid profile, inflammatory cytokines, adipocyte markers, antioxidants in the Poria cocos gold nanoparticles treated obese rats. To confirm the Poria cocos gold nanoparticles role on inhibiting the obesity induced metabolic disorders we analyzed the histopathological changes in cardiac tissues. Our physical characterization confirms the synthesized Poria cocos gold nanoparticles assure the distinctions of influential nanoparticles to be utilized for the treatment. The results from biochemical and histopathological analysis confirms Poria cocos gold nanoparticles is a persuasive antidiabetic, anti-inflammatory, antioxidant, anti-obesity drug. Overall our results authentically confirm Poria cocos gold nanoparticles is a potent anti-obesity drug and it also protects from obesity induced metabolic disorders.  相似文献   

15.
In the clinical laboratory, one of the most objective ways to perform the final review of measurement results is the use of the so-called plausibility control (i.e., set of procedures used to decide if a measurement result is valid or not according to established clinical and biological criteria). The present study is focused on the estimation of several prediction equations derived from pairs of biological quantities having a pathophysiological relationship and statistically correlated to detect objectively doubtful results in the context of plausibility control. These prediction intervals, that may be used alone or combined with other procedures involved in the plausibility control, are a very useful tool for the improvement of the final review of the laboratory results.  相似文献   

16.
In the present study we show that two-dimensional (2-D) maps together with immuno-detection allow the precise identification of important leukocyte differentiation and tumor markers (e.g., CD3 and CD5), and important cell cycle regulatory molecules such as cyclin dependent kinases, notably CDK6. In addition, the comparative evaluation of molecular expression (e.g., CD5) in maps developed with normal and lymphoma samples can provide reproducible and precise information regarding the molecular expression in different cell populations. Accordingly, we could detect a much increased level of expression of CD5 in mantle cell lymphoma, up to ten times higher than in the control. In addition, CD5 in tumor tissues seems to be microheterogeneous as compared to normal samples.  相似文献   

17.
Simple closed-form expressions are presented for the time-dependent rate coefficients of diffusion-influenced reactions in the presence of spherically symmetric potentials. For diffusion-controlled contact reactions, our expression reproduces the first two terms in both the short- and long-time expansions of the rate coefficient. At intermediate times, agreement with numerical results for the Debye-Hückel potential is found to be within a few percent for a wide range of parameters. For diffusion-influenced contact reactions (described by the radiation boundary condition), the agreement is even better. When the reactivity depends on the distance between the reactants (e.g., exponentially), our analytic result is less accurate, because it reproduces the two terms in the long-time expansion only to the linear order of the reciprocal of the diffusion coefficient. Our results should prove useful in the analysis of experimental data for diffusion-influenced reactions with centrosymmetric interaction potentials.  相似文献   

18.
通过对34例实施临终关怀的晚期患者回顾性讨论,体会到服务模式、死亡教育、心理安慰、环境因素及规范化管理是实施临终关怀的关键。  相似文献   

19.
Chemiluminescent reactions have found application in a number of commercial point-of-care and on-site testing devices. Notable examples include allergy tests (e.g., MASTpette, OPTIGEN® systems), flu tests (e.g., ZstatFlu®-II), cartridge-based immunoassay systems (FastPack® IP System, PATHFAST®), forensic tests for bloodstains, portable analyzers for biochip array assays (Evidence MultiStat), water quality tests (Eclox), air pollutants (e.g., oxides of nitrogen), and handheld devices for detecting explosives (e.g., E3500 Chemilux®). Many other point-of-care or on-site testing devices with a chemiluminescent end point have been devised on the basis of a variety of formats (e.g., cuvette, cassette, dipstick, test strip, microchip), but most have not progressed beyond a proof-of-principle or prototype stage.  相似文献   

20.
《Electrophoresis》2017,38(24):3155-3160
Messenger RNA (mRNA) profiling is a technique increasingly applied for the forensic identification of body fluids and skin. More recently, an mRNA‐based organ typing assay was developed which allows for the inference of brain, lung, liver, skeletal muscle, heart, kidney, and skin tissue. When applying this organ typing system in forensic casework for the presence of animal, rather than human, tissue is an alternative scenario to be proposed, for instance that bullets carry cell material from a hunting event. Even though mRNA profiling systems are commonly in silico designed to be primate specific, physical testing against other animal species is generally limited. In this study, human specificity of the organ tissue inferring system was assessed against organ tissue RNAs of various animals. Results confirm human specificity of the system, especially when utilizing interpretation rules considering multiple markers per cell type. Besides, we cross‐tested our organ and body fluid mRNA assays against the target types covered by the other assay. Marker expression in the nontarget organ tissues and body fluids was observed to a limited extent, which emphasizes the importance of involving the case‐specific context of the forensic samples in deciding which mRNA profiling assay to use and when for interpreting results.  相似文献   

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