The history of liquid chromatography started more than a century ago and miniaturization and automation are two leading trends in this field. Nanocolumn liquid chromatography (nano LC) and largely synonymous capillary liquid chromatography (capillary LC) are the most recent results of this process where miniaturization of column dimensions and sorbent particle size play crucial role. Very interesting results achieved in the research of extremely miniaturized LC columns at the end of the last century lacked distinctive raison d'être and only advances in mass spectrometry brought a real breakthrough. Configuration of nano LC-electrospray ionization mass spectrometry (LC-ESI-MS) has become a basic tool in bioanalytical chemistry, especially in proteomics. This review discusses and summarizes past and current trends in the realization of nano liquid chromatography (nano LC) platforms. Special attention is given to the mobile phase delivery under nanoflow rates (isocratic, gradient) and sample injection to the nanocolumn. Available detection techniques applied in nano LC separations are also briefly discussed. We followed up the key themes from the original scientific reports over gradual improvements up to the contemporary commercial solutions.
Komplementový systém je vnímám jako jeden z hlavních pilířů vrozené imunity, ale zároveň má také zásadní vliv na formování imunity adaptivní. V článku jsou, kromě významu komplementového systému, popsány jeho hlavní složky a jejich názvosloví, základní tři aktivační cesty, faktory a způsoby regulace jeho aktivity a klinické indikace k jeho vyšetřování. V části věnované laboratorní diagnostice komplementového systému je nejprve zdůrazněn význam preanalytické fáze, která hraje zásadní úlohu při jeho analýze, dále pak popsány jednotlivé metody jeho testování včetně doporučeného postupu od screeningu po podrobnou analýzu.
The complement system is an essential component of the innate immune system, but it also has a major impact in the formation of adaptive immunity. Its main components and their nomenclature, the three basic activation pathways, factors and regulation modes of its activity and clinical indications for its investigation are described. The importance of preanalytical phase, which plays a crucial role in analysis of complement system, following the methods and recommendations from screening to detailed analysis are delineated in the complement laboratory diagnosis section.
- MeSH
- Complement Activation physiology MeSH
- Enzyme-Linked Immunosorbent Assay MeSH
- Immune System Phenomena MeSH
- Immunodiffusion MeSH
- Clinical Laboratory Techniques * methods MeSH
- Complement System Proteins * physiology immunology MeSH
- Humans MeSH
- Microchemistry MeSH
- Guidelines as Topic MeSH
- Complement Hemolytic Activity Assay MeSH
- Check Tag
- Humans MeSH
Microreactor technology is an interdisciplinary field that combines science and engineering. This new concept in production, analysis and research is finding increasing application in many different fields. Benefits of this new technology pose a vital influence on chemical industry, biotechnology, the pharmaceutical industry and medicine, life science, clinical and environmental diagnostic. In the last few years, together with microplant development, a great part of research investigation is focused on integrated micro-systems, the so called micro-total-analysis-systems (μ-TAS) or lab-on-chip (LOC). They are devices that perform sampling, sample preparation, detection and date processing in integrated model. Cell sorting, cell lysis, single cell analysis and non-destructive single cell experiments on just one microreactor, makes the LOC platform possible. Clinical diagnostic devices are also leaning towards completely integrated, multiple sophisticated biochemical analyses (PCR amplification, cell lysis, separation and detection) all on a single platform and in real time. Special attention is also paid to the usage of microdevices in tissue. Tissue engineering is one of the most promising fields that can lead to in vitro tissue and organ reconstruction ready for implantation and microdevices can be used to promote the migration, proliferation and the differentiation of cells in controlled situations.
- MeSH
- Biophysics MeSH
- Biomedical Technology MeSH
- Biomedical Research MeSH
- Equipment Design MeSH
- DNA analysis MeSH
- Financing, Organized MeSH
- Immunoassay methods instrumentation MeSH
- Metabolomics methods MeSH
- Patch-Clamp Techniques instrumentation MeSH
- Microchemistry instrumentation MeSH
- Microchip Analytical Procedures MeSH
- Microfluidics methods instrumentation MeSH
- Microfluidic Analytical Techniques methods MeSH
- Microtechnology methods instrumentation MeSH
- Miniaturization methods instrumentation MeSH
- Polymerase Chain Reaction methods instrumentation MeSH
- Cell Separation methods instrumentation MeSH
- Tissue Engineering methods instrumentation MeSH
- Publication type
- Review MeSH
The use of trypsin for protein digestion is hampered by its autolysis and low thermostability. Chemical modifications have been employed to stabilize the enzyme. Modified trypsin (e.g. methylated) usually enables performing digestions at elevated temperatures, but it still produces autolytic peptides. In this work, unmodified bovine trypsin was subjected to a microscale affinity chromatography on Arginine Sepharose (ASE) or Benzamidine Sepharose (BSE), which utilized the principle of active-site ligand binding. Trypsin was retained on the sorbents in ammonium bicarbonate as a binding buffer. After washings to remove unbound impurities, the enzyme was eluted by arginine as a free ligand (from ASE) or by diluted hydrochloric acid (from BSE). MALDI-TOF mass spectrometry confirmed removal of large molecular fragments as well as autolytic and other background peptides. Consequently, the purified trypsin was tested for its performance in procedures of in-gel digestion of protein standards and selected urinary proteins from real samples. It has been shown that the affinity purification of trypsin decreases significantly the number of unmatched peptides in peptide mass fingerprints. The presence of arginine in the digestion buffer was found to reduce intensity of autolytic peptides. As a result, the described purification procedure is applicable in a common proteomic routine.
- MeSH
- Chromatography, Affinity MeSH
- Electrophoresis, Polyacrylamide Gel MeSH
- Microchemistry methods MeSH
- Peptide Mapping methods MeSH
- Protein Hydrolysates chemistry MeSH
- Proteinuria urine MeSH
- Cattle MeSH
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods MeSH
- Trypsin isolation & purification MeSH
- Animals MeSH
- Check Tag
- Cattle MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Nanomaterials are now produced in large quantities due to their useful properties different from other materials. Possible toxicity of nanomaterials is currently addressed and discussed. Using a modified Tollens process, an aqueous dispersion of Ag nanoparticles was prepared, on which their unique properties and changes of material characteristics when approaching nano dimensions can be demonstrated. Also, experiments regarding toxicity of nanoparticles were proposed. Toxicity of the nanoparticles was tested on Paramecium caudatum. Following the instruction, the students discover that the prepared Ag nanoparticles are much less toxic than ionic Ag. The proposed experiments bring interdisciplinary chemical, physical, and biological findings and knowledge.
- MeSH
- Anti-Infective Agents toxicity MeSH
- Chemistry Techniques, Analytical methods trends education MeSH
- Financing, Organized MeSH
- Colloids chemistry toxicity MeSH
- Humans MeSH
- Microchemistry methods education MeSH
- Nanoparticles microbiology toxicity utilization MeSH
- Nanotechnology methods trends education MeSH
- Paramecium caudatum drug effects MeSH
- Natural Science Disciplines methods trends education MeSH
- Silver toxicity MeSH
- Toxicity Tests methods utilization MeSH
- Education methods MeSH
- Check Tag
- Humans MeSH
The lipid components of pathogen cell membranes have been considered as a poor pharmacological target, due to their universal distribution and apparent homogeneity throughout living organisms. Among the rare exceptions to this view one could mention polyene antibiotics such as amphotericin, or peptide antibiotics such as the polymyxins and the gramicidins. In the last two decades, however, the above notion has been challenged by two main lines of discovery; first, natural antimicrobial peptides (AMPs) that kill pathogens by interaction with phospholipids and membrane permeabilization, and secondly, cell-penetrating peptides (CPPs), capable of introducing into cells a variety of cargoes in the absence of specific receptors, again by interaction at some point with membrane phospholipids. For both AMPs and CPPs, the pharmacological proof-of-concept has been successfully demonstrated, and promising applications as nanobiotechnological tools have been envisaged though not hitherto materialized in clinical settings. In this review we briefly examine the pros and cons of these two classes of therapeutic agents, as well as strategies aimed at rationalizing and expanding their potentiality.
- MeSH
- Drug Resistance, Microbial genetics immunology MeSH
- Financing, Organized MeSH
- Communicable Diseases drug therapy MeSH
- Antimicrobial Cationic Peptides genetics drug effects MeSH
- Humans MeSH
- Lipopolysaccharides biosynthesis MeSH
- Microchemistry methods trends MeSH
- Peptides genetics metabolism drug effects MeSH
- Cell Membrane Permeability genetics immunology drug effects MeSH
- Plants MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Review MeSH
Miniaturizace je jedním z velkých témat současnosti a v chemii se také uplatňuje. Z chemických reakcí ve větších měřítkách, v baňkách, se přechází na miniaturizované systémy mikroreaktorů. Postupným vývojem byly optimalizovány materiály i techniky pro práci v mikroměřítku. Mnohé studie se zabývají rozborem dokonce jednotlivých molekul, často se jedná o makromolekuly typu DNA, nebo proteinu. Je možné vytvářet reaktory s objemem attolitrů. Některé experimenty slibují do budoucna užitečnou aplikaci v medicíně, ale i dalších oborech.
Today, miniaturization is one of the top topics and chemistry undergoes it as well. Chemical reactions were usually performed in flasks but at the present time, there are many endeavours to miniaturize them to microreactor systems. Used methods and materials are still being optimised to be able to work in this micro and nano-scale volume. There are many experiments studying even single molecules (often macromolecules like DNA or proteins). It is possible to create reactors even of attoliter volume. Therefore applications in medicine and other disciplines can be expected in the future.
Microparticles are an intensively studied field of pharmaceutical technology. Reduced side effects and new drug delivery methods are some of the advantages they offer. The aim of this study was to develop and optimize the preparation of Eudragit® RS 100 microparticles containing diclofenac sodium. The emulsification - solvent evaporation method is one of the most common and widely used microencapsulation techniques. The influence of few selected processes and formulation variables on the microparticle characteristics was investigated for the emulsion of methanol in liquid paraffin. The following conditions were selected: polymer-to-drug ratio 2:1, emulsification with 1% Span® 80 at 19000 rpm and 40 °C. The dissolution of the drug from microparticles was controlled by diffusion.
- MeSH
- Administration, Oral MeSH
- Diclofenac administration & dosage pharmacokinetics pharmacology MeSH
- Microscopy, Electron methods utilization MeSH
- Emulsions MeSH
- Drug Industry methods trends MeSH
- Gastrointestinal Tract drug effects MeSH
- Clinical Laboratory Techniques instrumentation utilization MeSH
- Dosage Forms MeSH
- Delayed-Action Preparations pharmacokinetics pharmacology MeSH
- Humans MeSH
- Methanol MeSH
- Methylmethacrylates pharmacokinetics pharmacology MeSH
- Microchemistry history methods MeSH
- Drug Carriers pharmacokinetics pharmacology MeSH
- Polymers therapeutic use MeSH
- Solubility MeSH
- Statistics as Topic MeSH
- Check Tag
- Humans MeSH
OBJECTIVES: Some individually-housed male mice behave aggressively during encounters with strange males, while others are timid or sociable in the same situation. The objective of the present study was to examine concentrations of glutamate, aspartate, and GABA in the brain of aggressive, timid, and sociable mice. METHODS: Random-bred albino mice were housed individually for three weeks and then classified in three groups (aggressive, timid, and sociable mice) according to their behavior during social interaction with non-aggressive group-housed male mice in a neutral cage. One week after categorization, by means of the social conflict test, levels of glutamate, aspartate, and GABA were measured by in vivo microdialysis of the medial prefrontal cortex (mPFC) of the isolated and group-housed mice. RESULTS: Sociable mice had almost triple the levels of GABA in their mPFC than aggressive or timid mice. No significant differences in aspartate and glutamate levels were found in these three types of individually-housed mice. Forebrain chemistry of group-housed mice did not differ from that of individually-housed mice with the exception of levels of glutamate and GABA which were significantly lower in group-housed mice than in sociable individually-housed mice. CONCLUSION: The present results suggest that GABA might play a role in sociable behavior. Results also corroborate other findings indicating that the GABAergic system represents an important molecular and neuronal substrate for the selective attenuation of anxiety and aggression.
- MeSH
- Aggression physiology MeSH
- Models, Biological MeSH
- Behavior, Animal physiology MeSH
- Excitatory Amino Acids analysis metabolism MeSH
- gamma-Aminobutyric Acid analysis metabolism MeSH
- Aspartic Acid analysis metabolism MeSH
- Glutamic Acid analysis metabolism MeSH
- Microchemistry methods MeSH
- Microdialysis methods MeSH
- Brain metabolism MeSH
- Mice, Inbred ICR MeSH
- Mice MeSH
- Shyness MeSH
- Social Behavior MeSH
- Social Desirability MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
32 s. : il. ; 21 cm
- MeSH
- Biophysics MeSH
- Biosensing Techniques MeSH
- Microchemistry MeSH
- Optical Phenomena MeSH
- Surface Plasmon Resonance MeSH
- Publication type
- Academic Dissertation MeSH
- Conspectus
- Biochemie. Molekulární biologie. Biofyzika
- NML Fields
- fyzika, biofyzika
