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We developed a simple, paper‐based device that enables sensitive detection by mass spectrometry (MS) without solid phase extraction or other sample preparation. Using glass fiber filter papers within a 3D printed holder, the device employs electrokinetic manipulations to stack, separate, and desalt charged molecules on paper prior to spray into the MS. Due to counter‐balanced electroosmotic flow and electrophoresis, charged analytes stack on the paper and desalting occurs in minutes. One end of the paper strip was cut into a sharp point and positioned near the inlet of a MS. The stacked analyte bands move toward the paper tip with the EOF where they are ionized by paper spray. The device was applied to analysis of PFAS in tap water with sub part‐per‐trillion detection limits in less than ten minutes with no sample pretreatment. Analysis of opioids in urine also occurs in minutes. The crucial parameters to enable stacking, separation, and MS ionization of both positively and negatively charged analytes were determined and optimized. Experimental and computational modeling studies confirm the electrokinetic stacking and analyte transport mechanisms. On‐paper separations were carried out by stacking analyte bands at different locations depending on their electrophoretic mobility, achieving baseline separation in some cases. [ABSTRACT FROM AUTHOR]

Microfluidic free‐flow electrophoresis (μ‐FFE) is widely used for continuous separation of charged analytes. However, μ‐FFE is limited in the separation of analytes with the same electrophoretic mobility. In this work, we developed a novel microfluidic free‐flow paper electrochromatography (μ‐FFPE) by combining μ‐FFE with filter paper‐based chromatography, enabling continuous separation of analytes through the mechanism of both μ‐FFE and paper chromatography. Numerical simulation was applied to demonstrate the advantages of adding filter paper as the stationary phase of μ‐FFE. With the filter paper, a more stable separation system was achieved. The device was applied to the separation of simple mixtures of dyes and complex mixtures of glycans. With the μ‐FFPE fractionation, much more glycans and glycan types can be identified by LC‐MS, demonstrating the value of the method in biological analysis. The μ‐FFPE can provide a new platform for the separation and analysis of various biological molecules. [ABSTRACT FROM AUTHOR]

Plasmonic metal nanostructures generate vivid colors with high spatial resolution. Active control of plasmonic pixels by electrical means, which is compatible with integrated circuit technologies, is a promising technique for dynamic full color reflective display. However, the development of electrical plasmonic display is still limited by the difficulties in cost‐effective construction of active plasmonic pixels over large areas. This study demonstrates the achievement of electrical plasmonic display in full color by electrophoretic movement control of plasmonic noble metal nanocrystals in an organic electrolyte solvent. The persistent issues of nanoparticle aggregation and irreversible deposition in electrophoresis are addressed through appropriate surface modifications of the plasmonic nanocrystals, enabling them as advantageous nanoscale colorful pigments with long‐term durability. A weak electric field therefore allows color display with high contrast, high saturation, and electrical reconfigurability. The ink containing plasmonic pigments is further assembled into microfluidic chips to display different characters. The strategy will pave the way towards the development of plasmonic electronic paper in full color. [ABSTRACT FROM AUTHOR]

The article focuses on the development and applications of bright electronic skin technology. It presents simplified electrode geometries and transparency, a novel concept for built-in gray levels, and aperiodic cell geometries. It reveals that in electronic-paper displays, gray scale is basically realized by the addition of patterned electrodes and detailed driving schemes.

A common drawback of paper-based separation devices is their poor detection limit. In this study, we combined field-amplified sample stacking with moving reaction boundary electrophoresis on a paper chip with six array channels for the parallel separation and concentration of multiple samples. With a new hyphenated technique, the brown I2 from the Fe3+/I− oxidation-reduction reaction emerged near the boundary between the dilute ethylene diamine tetraacetic acid and potassium iodide and highly concentrated KCl solutions. For the separation and concentration of three components, Cr3+, Cu2+, and Fe3+, the Fe3+ detection limit was improved at least 266-fold by comparing the hyphenated technique with moving reaction boundary electrophoresis. The detection limit of Fe3+ was found to be as low as 0.34 ng (20 μM) on the paper chip. We also demonstrated the analysis of a real sample of four metal ions, with detection limits as follows: 0.16 μg Cr3+, 1.5 μg Ni2+, 0.64 μg Cu2+, and 1.5 μg Co2+. The synergy of field-amplified sample stacking and moving reaction boundary electrophoresis in the micron paper-based array channels dramatically improved the detection limit and throughput of paper-based electrophoresis. [ABSTRACT FROM AUTHOR]

The world's first mass production three-particle electrophoretic display has been launched. E Ink SpectraTM displays utilize black, white and red engineered particles in a colorless solvent to achieve red plus black/white independent optical states without a color filter array. The three types of particles have different properties and are well controlled so they respond differently to various electric fields. The Spectra electrophoretic ink is filled and then sealed in a thin film Microcup® structure using a roll to roll process and the output imaging film can be easily cut to any shape and size and then laminated to TFT or segmented backplanes to form display modules. [ABSTRACT FROM AUTHOR]

Hereditary hemolytic anemia (HHA) is a heterogeneous group of disorders due to genetically caused defects in red blood cell membrane structure, enzymes, heme and globin synthesis, erythroid proliferation, and differentiation. Traditionally, the diagnostic process is complex and includes a plethora of tests from routine to highly specialized ones. The inclusion of molecular testing has significantly improved the diagnostic yield. The value of molecular testing is broader than just rendering the correct diagnosis, as it may also guide therapeutic decisions. As more molecular modalities become available for clinical use, it is imperative to understand their benefits and disadvantages pertaining to the HHA diagnostics. Re‐evaluation of the traditional diagnostic workflow may also bring forth additional benefits. This review focuses on the current state of molecular testing for HHA. [ABSTRACT FROM AUTHOR]

We have successfully demonstrated a control device for viewing angle that enables switching two states between a wide-viewing angle and a narrow-viewing angle. It consists of a light-transmitting portion formed with an array of optical micro-rods and shielding/transmitting changeable portion designed with electrophoretic materials. The response time from the narrow-viewing to wide-viewing angle was one second at 20 V of applied voltage. [ABSTRACT FROM AUTHOR]

This article discusses paper electrophoresis patterns of enzymes involved in polyglucoside synthesis in oscillatoria princeps and its low temperature strains. The technique of paper partition chromatography and paper electrophoresis for the study of genetically different tissues have recently found application in the field of genetic studies. These methods should prove of considerable interest in the detection of differences between enzymes having the same properties and functions in the different species.

The role of Β-glucose 1,6-bisphosphate as a cofactor in the reaction catalyzed by the phosphoglucomutase for Β-glucose 1-phosphate (Β-phosphoglucomutase) has been examined in purified extracts of Euglena gracilis var. bacillaris. 1. The incubation of Β-glucose 1-[32P]phosphate with Β-phosphoglucomutase in presence of high concentrations (0.1 mM) of a commercial preparation of α-D(+)-glucose 1,6-bisphosphate (prepared synthetically) yielded a labelled compound running electrophoretically and chromatographically as the sugar bisphosphate. Specificity studies with Β-phosphoglucomutase and muscle phosphoglucomutase (α-phosphoglucomutase) strongly suggest that the compound formed is Β-glucose 1,6-[32P]bisphosphate. The results would also indicate that the commercial preparation of α-D(+)-glucose 1,6-bisphosphate contains Β-glucose 1,6-bisphosphate as contaminant. 2. When synthetic Β-glucose 1-phosphate preparations were purified by paper chromatography and then incubated with Β-phosphoglucomutase, no glucose 6-phosphate could be detected. On the other hand the reaction readily took place when challenged with the chromatographic fraction that runs as sugar bisphosphate. Upon analysis with etectrophoresis, chromatography and weak acid hydrolysis, and experiments with Β-phosphoglucomutase and α-phosphoglucomutase it was concluded that this compound is Β-glucose 1,6-bisphosphate. 3. It was established that the natural α-D(+)-glucose 1,6-bisphosphate not only fails to sustain the reaction catalyzed by Β-phosphoglucomutase but rather inhibits the reaction when added to the whole Β-phosphoglucomutase system, it was also demonstrated that Β-glucose 1,6-bisphosphate acts as inhibitor of the α-phosphoglucomutase system. 4. These results show for the first time that Β-glucose 1,6-bisphosphate is an active and necessary participant in the reaction catalyzed by Β-phosphoglucomutase. The role played by Β-glucose 1,6-bisphosphate in this reaction would be essentially the same as that of the α-anomer in the reaction catalyzed by α-phosphoglucomutase. [ABSTRACT FROM AUTHOR]

The stretchable and flexible electrophoretic image display device using the stretchable polymer film coated with the electrically conductive layer was produced. The stretchable polymer film was composed primarily of epoxy resin and used carbon nanotube for an electrically conductive layer. This stretchable polymer film has the property of an electrical insulation, a high heat-resistance, a low elasticity and a good elastic recovery. [ABSTRACT FROM AUTHOR]

Succinate dehydrogenase flavocoenzyme (‘SD-flavin’), previously shown to be an 8α-substituted riboflavin derivative containing a tertiary nitrogen homoconjugated to the flavin nucleus, was subjected to further hydrolysis and to reduction under acid conditions. Both conditions resulted in the liberation of 1 mole of histidine per mole of flavin. This proves histidine to be the covalent link between flavin and peptide backbone in succinate dehydrogenase and imidazole to be the tertiary nitrogen function homoconjugated to the flavin. 8α-Histidyl-riboflavin has been synthesized starting from riboflavin chemically and shown to be completely identical with the natural product in optical, ESR and NMR spectra, pH-fluorescence curve and behavior on thin-layer and paper chromatography, as well as paper electrophoresis. [This equation cannot be represented into ASCII Text] 3. Both the natural compound isolated by acid hydrolysis of flavin peptide and the synthetic one contain two isomers, which may be separated by high voltage electrophoresis. The isomers appear to be the N(1)- and N(3)-imidazole substituted compounds. Digestion of the flavin peptide with aminopeptidase M yields only one isomer but on treatment with 6-N HCl this is gradually converted to a mixture of the two isomers. The absolute assignment of the natural isomer is suggested as 8α-[N(3)-histidyl]-riboflavin on the basis of imidazole quaternization with CH3I, reductive cleavage of the flavin-imidazole bond and identification of the methyl-histidine liberated as 1-methyl-histidine. [ABSTRACT FROM AUTHOR]

RETRACTION: R. Bakalova, H. Ohba, Z. Zhelev, T. Kubo, M. Fujii, M. Ishikawa, Y. Shinohara, and Y. Baba, ‘Antisense inhibition of Bcr‐Abl/c‐Abl synthesis promotes telomerase activity and upregulates tankyrase in human leukemia cells,' FEBS Letters 564, no. 1–2 (2004): 73–84, https://doi.org/10.1016/S0014‐5793(04)00318‐7.The above article, published online on 9 April 2004 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors; the journal Editor‐in‐Chief, Michael Brunner; FEBS Press; the National Institute of Advanced Industrial Science and Technology (AIST); and John Wiley and Sons Ltd.Following publication, concerns were raised by a third‐party regarding several figures in the article. The subsequent institutional investigation conducted by the AIST revealed: Inappropriate duplication of image panels within the article, between the β‐actin loading controls for 4 and 6 days in the Western blot of Fig. 2A K‐562; between the subpanels of the electrophoresis blots in Fig. 4A K‐562 and Jurkat cells; and between the subpanels of the electrophoresis blots in Fig. 6B. Band insertion in the Western blot of Fig. 6A p210 Bcr‐Ab lane. Inappropriate duplication of images between this article (Fig. 2A K562 β‐actin and Fig. 4B K562 6 days treatment bands) and an earlier publication from 2003 by an overlapping group of authors representing different experimental conditions. Inappropriate duplication and modification of an image between this article (Figure 3A2) and an earlier publication from 2004 by an overlapping group of authors representing different experimental conditions. Therefore, the conclusions of the paper are substantially compromised and the institute has recommended the paper to be retracted. The editors of the journal agree with the retraction based on the institutional investigation. [ABSTRACT FROM AUTHOR]

The article presents information on various forthcoming papers to be published in the March 15, 1984 issue of the "European Journal of Biochemistry." Some of them are "Studies on the Structure and Expression of Escherichia Coli pyrC, pyrD and pyrF Using the Cloned Genes," "Rat-Liver Lysosomal Sialidase. Solubilization, Substrate Specificity and Comparison With the Cytosolic Sialidase," "Diamine-Induced Dissociation of the First Component of Human Complement," "Evidence for the Glycoprotein Nature of Retina Glycogen," and "Mapping of Surface Glycoproteins of Trypanosoma Cruzi by Two-Dimensional Electrophoresis. A Correlation With the Cell Invasion Capacity."

Exercise can alter gene transcriptional and protein translational rates leading to changes in protein abundance toward adaptation to exercise. We investigated the alterations in protein abundance in skeletal muscle after one bout of an exhaustive exercise through proteomic analysis. Gastrocnemius muscles were sampled from non-exercised control rats and from rats exercised on a treadmill with incremental increases in speed until exhaustion (approximately 30 min). Rats were sacrificed 3 and 24 h after exercise cessation. Two-dimensional gel electrophoresis was performed and spots with a significant alteration in relative volume were identified by mass spectrometry. Six spots presented statistically significant altered abundances after exercise. The spots identified as the metabolic related proteins triosephosphate isomerase 1, glyceraldehyde-3-phosphate dehydrogenase, the β subunit of pyruvate dehydrogenase E1 and carnitine palmitoyltransferase 2 were all more abundant after exercise. One spot identified as heat shock cognate 70 was also more abundant after exercise. One spot demonstrated a decreased abundance after exercise and was identified as α-actin. These results suggest that a single session of exhaustive incremental exercise in untrained muscle can alter thin filaments synthesis/degradation rate and enhance cytosolic and mitochondrial proteins synthesis. The identified proteins may be important to a general preconditioning of skeletal muscle for subsequent exercise sessions. [ABSTRACT FROM AUTHOR]

This paper uses zone electrophoresis, one of the most frequently used tools in molecular biology, to explore two ideas derived from Hans-Jörg Rheinberger's reflections on experiments. First, the constraining role played by technical objects--instrumentation and material conditions--in the production of knowledge or epistemic things. Second, the production of interconnected experimental systems by such technical objects, which results in the unexpected entanglement of research fields and experimental cultures. By the beginning of the 1960s, the inception of zone electrophoresis in laboratories around the world transformed--some say, revolutionized--the study of proteins. Even today, electrophoresis continues to open research venues and questions in biomedicine, molecular biology, human genetics, and in the field of molecular evolution. In my essay, I seek to look at the interconnected lives of zone electrophoresis and address the broader social, and even global context, in which this apparently humble technique became a salient tool in the production of biological knowledge. In so doing, I aim to take the past and present of the history and historiography of experimental systems to the future, where experiments and technologies are interrogated as they are used in different geographies and contexts, including contexts of poverty. [ABSTRACT FROM AUTHOR]

A neurodepressing hormone has been isolated and purified to homogeneity from aqueous extracts of 2000 eyestalks of the Mexican crayfish Procambarus bouvieri (Ortmann). Purification was achieved by gel filtration on Sephadex G-25 and G-15, and preparative paper electrophoresis at four pH values (1.8, 3.6, 6.0 and 10.0). The recovery of hormone activity was 85% and the specific activity was 4.0 × 104 limes that of the starting material. The hormone is a thermostable peptide of approximately 1200 molecular weight and composed of neutral amino acids. No N-terminal group could be found. From its electrophoretic behavior it is concluded that the C-terminal group is also blocked. [ABSTRACT FROM AUTHOR]

Natural rubber is bio‐based rubber, which plays an important role in carbon neutralization to reduce carbon dioxide emissions. It is widely used in the national economy because of its strain‐induced crystallization properties. However, the preparation process for natural rubber is backward and in urgent need of reform. Electrophoretic coagulation, as a new natural rubber coagulation process, was proposed in this paper. We designed electrophoresis equipment and optimized it through finite element analysis. Compared with traditional coagulation methods electrophoretic coagulation has outstanding advantages: high efficiency, no wastewater, and low odor. Compared with commercial natural rubber, electrophoretic coagulated natural rubber has a stronger supramolecular structure, better mechanical performances, and dynamic compression heat buildup. We also revealed the relationship between the structure and properties of different natural rubber. [ABSTRACT FROM AUTHOR]

Kanamycin is an antibiotic, isolated from Streptomyces kanamyceticus, which is used to treat serious bacterial infections. The fact that the present radioligand 99mTc-kanamycin used for diagnosis is short-lived, raised a need to label and study kanamycin with one of the most important beta (β) radiation emitting isotope 177Lu. Labeling yield of 177Lu-kanamycin was confirmed by different chromatography techniques such as paper chromatography, TLC, HPLC. Several experiments were performed to optimize labeling with changing reaction conditions such as pH, temperature, amount of ligand, and reaction time. In vitro stability analysis was performed incubation with human serum. Electrophoresis analysis was also conducted to determine the charge on 177Lu-kanamycin. The biodistribution and scintigraphy were performed in normal mice and rabbit, respectively, at different time intervals of postinjection. 177Lu-kanamycin was prepared with very high yield (~100%), with excellent stability in vivo and in vitro (>99% 6 hr postprep.), at pH 7. Maximum labeling was achieved at less reaction time (15 min), with maximum conjugation of the ligand (12.5 mg) with 177Lu. Electrophoresis analysis showed net neutral charge. The radioligand showed rapid clearance from body in biodistribution and scintigraphy studies. The preparation 177Lu-kanamycin could be used as a radio-pharmaceutical for infection imaging purpose, especially when transporting the radioligand to long-range distances. [ABSTRACT FROM AUTHOR]

The nitrogenous materials released by the blue-green phycobiont (Nostoc sp.) of five lichens have been examined by means of high voltage paper electrophoresis. They were found to be a mixture of substances with similar electrophoretic characteristics to the materials released by the same algae when grown in pure culture, and were largely peptide in nature. A more detailed study was made of the components released into their growth media by the three strains of Nostoc isolated from Peltigera aphthosa, P. canina and P. polydactyla. From about twelve compounds demonstrable by electrophoresis, the six most abundant were examined for their amino acid composition. The only finding strikingly different from existing data was a generally low level of serine. Molecular weight estimates by means of gel filtration indicated that most of the substances had molecular weights of approximately 1100, with substances with molecular weights of about 300 forming a smaller important group, although materials with a wide range of molecular weights were evidently present and low molecular weight material could also be important. [ABSTRACT FROM AUTHOR]

Low molecular weight solutes released during mild acid hydrolysis of the lipopolysaccharide of Pseudontoytas aeruginosa were isolated from the fraction containing the partially degraded polysaceharide, by successive chromatography on columns of Sephadex G-75 and G-10, followed as necessary) by preparative high voltage paper electrophoresis The major components identified were 2-keto-3-deoxyoctonic acid, basic amino acids (free and bound), inorganic orthophosphate, ethanolamine phosphate and ethanolamine pyrophosphate. Ethanolamine pyrophosphate has not previously been found in acid hydrolysates of lipopolysaceharides. Ethanolamine phosphate and some of the orthophosphate were apparently produced by breakdown of ethanolamine pyrophosphate [ABSTRACT FROM AUTHOR]

Peptide B, the N-terminal fragment of thioredoxin obtained by cyanogens bromide treatment was aminoethylated and digested with pepsin. Eight peptides were separated by high voltage paper electrophoresis and chromatography and characterized with respect to amino acid sequence. The results account for all 37 residues peptide B. The N-terminal sequence of peptide B was determined as: Ser-Asp-Lys-Ile-Ile-His-Leu-Thr-Asp-Asp-Ser-Phe. [ABSTRACT FROM AUTHOR]

Synthetic active matters are perfect model systems for non‐equilibrium thermodynamics and of great potential for novel biomedical and environmental applications. However, most applications are limited by the complicated and low‐yield preparation, while a scalable synthesis for highly functional microswimmers is highly desired. In this paper, an all‐solution synthesis method is developed where the gold‐loaded titania‐silica nanotree can be produced as a multi‐functional self‐propulsion microswimmer. By applying light, heat, and electric field, the Janus nanotree demonstrated multi‐mode self‐propulsion, including photochemical self‐electrophoresis by UV and visible light radiation, thermophoresis by near‐infrared light radiation, and induced‐charge electrophoresis under AC electric field. Due to the scalable synthesis, the Janus nanotree is further demonstrated as a high‐efficiency, low‐cost, active adsorbent for water decontamination, where the toxic mercury ions can be reclaimed with enhanced efficiency. [ABSTRACT FROM AUTHOR]

Agarose gel electrophoresis is the most useful and revolutionary process for separating, analyzing, identifying, and purifying different DNA fragments (in shape or size) from any cell or organism. This process is an amalgamation of four associated techniques viz. gel casting, electrophoresis, staining, and imaging, which are consecutively accomplished to get desired results. Various types of commercialized/non‐commercialized device and reagent kits are available with manufacturers to perform the associated techniques with simplicity. All these devices need secure space, separate operating procedures, and timely maintenance for the long run. In the absence of a low‐cost integrated electrophoresis device that can be utilized for the complete gel electrophoresis process, untimely operational failure of any individual equipment affects the experiment. In this paper, we describe an integrated gel electrophoresis instrument, which provides all facilities for agarose gel casting, electrophoresis, staining, and imaging techniques without any exposure to harmful chemicals. Construction of this four‐in‐one instrument in the laboratory requires off‐the‐shelf and pre‐existing components. Overall estimated cost is nearly US$ ∼222.00; and it can be assembled within 1 h, which makes it an inexpensive, user‐friendly, and effortless system. It has proved to be advantageous for researchers working in wide varieties of laboratories on the evaluation of nucleic acids. [ABSTRACT FROM AUTHOR]

Programmed step electric field strength is a simple-to-use technique that has already been reported to be effective to enhance the efficiency or speed of DNA electrophoresis. However, a global understanding and the details of this technique are still vague. In this paper, we investigated the influence of programmed step electric field strength by theoretical calculation and concentrated on a basic format named as two-step electric field strength. Both subtypes of two-step electric field strength conditions were considered. The important parameters, such as peak spacing, peak width, resolution, and migration time, were calculated in theory to understand the performance of DNA electrophoresis under programmed step electric field strength. The influence of two-step electric field strength on DNA electrophoresis was clearly revealed on a diagram of resolution versus migration time. Both resolution and speed of DNA electrophoresis under two-step electric field strength conditions are simply expressed by the shape of curves in the diagram. The possible shapes of curve were explored by calculation and shown in this paper. The subtype II of two-step electric field strength brings drastic variation on the resolution. Its limitations of enhancement and deterioration of resolution were predicted in theory. [ABSTRACT FROM AUTHOR]

Capillary electrophoresis coupled with electrochemical detection can be a powerful analysis tool; however, previous methods developed to integrate these two techniques can often times be fragile and have alignment issues such that there are no commercially available approaches. In this paper, we present the use of a 3D‐printed Wall‐Jet Electrode device for integrating capillary electrophoresis with electrochemical detection. A pressure mobilization step was also utilized to further reduce noise by allowing the electrophoresis separation step to continue only until the first analyte was close to elution. Then, the separation voltage was terminated and pressure‐based flow was used for elution of the analyte bands onto the electrode surface with a wall‐jet configuration. It is shown that the pressure‐based elution is beneficial for the reduction of baseline noise and elimination of field effects. A mixture of catecholamines were separated to demonstrate effectiveness of the system. In addition, the system was coupled with a Beckman Coulter commercial capillary electrophoresis instrument in a straightforward manner. The system was also shown to be effective in separations done with a high ionic strength physiological buffer. This 3D printing approach can be used by researchers to utilize electrochemical detection on commercial capillary electrophoresis systems by downloading the provided STL and/or CAD files. [ABSTRACT FROM AUTHOR]

Abnormally high amounts of low molecular weight mannose-rich carbohydrate material were found in the urine of an Angus calf with mannosidosis. At least five oligosaccharide fractions were detected by paper chromatography. The most abundant compound was purified by gel chromatography, zone electrophoresis, and two consecutive preparative paper chromatographic steps. The yield was 10 mg/liter of urine. From structural studies including nuclear magnetic resonance spectroscopy, optical rotation, sugar analysis, methylation analysis, and partial enzymatic degradation the following structure was deduced: α-D-Manp- (1 → 6)-β-D-Manp-(1 → 4)-β-D-GlcNAcp-(1 → 4)-β-D-GlcNAcp-(1 → 4)-D-GlcNAc. This oligosaccharide is distinct from all the oligosaccharides previously described which are excreted by patients with mannosidosis. [ABSTRACT FROM AUTHOR]

The methylation of HeLa cell ribosomal proteins has been studied by paper electrophoresis separation of the peptides produced after trypsin digestion of individual ribosomal proteins. Methylation in vivo was detected by 3H labeling of peptides from cells that had been incubated with a mixture of [methyl-3H]methionine plus [35S]methionine, the incorporation of the 3H-labeled amino acid methionine being corrected by the 35S uptake. Each methylated peptide thus represented at least one methylation site (one or more methylated amino acids and their adjacent amino acid sequence). Eleven ribosomal proteins were found to be methylated. As many as five methylation sites were present in one ribosomal protein. In several ribosomal proteins some sites were methylated when ribosome synthesis was suppressed with low levels of actinomycin D, while other sites were not. Therefore, some of the sites in a given protein were apparently methylated in mature ribosomes, while other sites were methylated during ribosome processing. The methyl-group-specific labeling of some sites, but not others, was suppressed by cycloheximide, thus suggesting that the methylation of some sites was dependent on protein synthesis. A cell-free system from cultured HeLa cells is described, which reproduces the methylation pattern of ribosomal proteins in vivo in two ways: methylation was observed both in vivo and in vitro (a) in the same ribosomal proteins; and (b) in the same methylation sites of a given ribosomal protein. In addition, our data in vitro suggest that the methylation of some human ribosomal protein sites may involve a methyl donor other than S-adenosylmethionine. [ABSTRACT FROM AUTHOR]

The aim of the present study was the quantification of proteins present in crevicular fluid obtained from individual sulci, and to this effect simplified micromethods for the quantification of individual proteins were developed. Unstimulated, resting crevicular fluid from healthy crevicular spaces (i.e. in the absence of clinically detectable inflammation) of dogs and humans was collected for 3 minutes, either in microcapillary glass tubes or with the aid of filter paper strips. Quantification of proteins was done by radial immunodiffusion without the pooling of samples or by immunoelectrophoresis, without eluting from the papers. The concentrations of albumin and fibrinogen in crevicular fluid so determined proved to be significantly lower than plasma concentrations. These results strengthen the concept that capillary dynamics in healthy gingivae are similar to those in general tissue capillary beds and that gingival fluid is a plasma transudate. However, due to ever present sub-clinical inflammation and other factors, it is improbable that fluid from even healthy sulci is a true transudate. [ABSTRACT FROM AUTHOR]

Mild acid hydrolysis of the glycolipid derived @om a Salmonella Rd2 mutant led to the liberation of three major split products which, after separation by electrophoresis, were identified as free 2-keto-3-deoxyoctonate (KDO), KDO-7-phosphorylethanolamine, and L-glycero-α-D-mannoheptosyl-l,5-KDO. [ABSTRACT FROM AUTHOR]

In order to reveal the genetic relationship of tetraploids and pentaploids in the agamospermous species Taraxacum albidum Dahlst., an allozyme study was carried out. Approximately 200 plants putatively identified as T. albidum were collected mainly from the Kyushu Island of Japan, and analyzed by enzyme electrophoresis. Two multilocus genotypes at 14 presumptive loci of nine enzymes, Type A and Type B, were detected. Most of the sample plants showed uniclonal Type A, which corresponds to "T. albidum" as reported in our previous paper. Type B, which is also uniclonal, was found at fewer localities and was clearly different from Type A in the allele composition of pgi‐2 and pgm‐1, as well as in the allele dosage at mdh and sod‐1. By means of flow cytometry and chromosome count, the ploidy levels of Type A and Type B were shown to be pentaploid and tetraploid, respectively. A comparison of the allele composition suggests a hybrid origin of pentaploid T. albidum (Type A) from an unreduced gamete of Type B and a reduced gamete of any diploid Taraxacum species. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) suspended in an N, N′-dimethylformamide (DMF) solvent underwent electrophoretic deposition (EPD) on carbon paper (CP) electrodes. X-ray computed micro-tomography (XMT) indicates a 24 % increase in the specific surface area of CP modified with rGO in comparison to the untreated sample. Furthermore, XMT confirms that the deposition also penetrates into the substrate. Raman analysis shows that the rGO deposited is more amorphous than the CP electrode. A significant reduction in charge-transfer resistance of the VO2+/VO2+ reaction is also observed (from impedance measurements) in modified samples in comparison to untreated CP electrodes. [ABSTRACT FROM AUTHOR]

- The active-matrix electrophoretic display (AMEPD) has been commonly used for the applications of smart handheld reading devices such as e-books and e-newspapers. This paper presents a controller IC design for the AMEPD backend system which reduces the total hardware cost compared to that of the conventional design. By contrast, this study also provides a driving method for image displays. The prototyped controller is connected to a 6-in. AMEPD panel, and good display quality has demonstrated the effectiveness of the proposed controller design. [ABSTRACT FROM AUTHOR]

Activity of mammalian pyruvate dehydrogenase complexes from all sources so far tested is regulated by phosphorylation involving three sites. To facilitate understanding of the precise biological roles of the individual phosphorylation sites a method has now been developed, using pig heart [32P]phosphorylated complexes, which enables unambigous measurement of their occupancies. Established methods of tryptic digestion give two peptides that contain the three phosphorylation sites: TA contains sites 1 and 2; TB contains site 3. Thus, while occupancy of site 3 may be determined unequivocally by tryptic digestion, occupancies of sites 1 and 2 cannot. The present paper shows that peptide TA may be specifically and quantitatively cleaved by formic acid at an Asp-Pro bond located between the two phosphorylation sites. Equal amounts of two new peptides each containing a different phosphorylation site (site 1 or site 2) are produced. The 32P-labelled peptides may be completely separated and quantified by high-voltage paper electrophoresis at pH 2. A combination of tryptic digestion (determination of 32P in site 3) and-formic acid cleavage of peptide TA (determination of 32P in sites 1 and 2) thus enables unequivocal assignment of occupancies of individual phosphorylation sites to >95 % accuracy. This method has been used to show that during phosphorylation and inactivation of pig heart complexes (inactivated to between 1.5% and 90%) >98% of the observed inactivation was primarily attributable to phosphorylation of site 1; the contribution of site 2 was <2 % if at all. Relative initial rates of phosphorylation, site 1:site 2:site 3 were approximately 90:3:1. [ABSTRACT FROM AUTHOR]

The polysaccharide moiety of the lipopolysaccharide (polysaccharide I) from Escherichia coli F492 (08:K27-:H-) and the polysaccharide (polysaccharide II) from the rfa mutant F612 (derived from F492) were isolated by extraction with 450% aqueous phenol at 65 °C. Polysaccharide I was obtained in 1–2% yield (based on dry bacteria). It contained mannose (83.5%), glucose (5.7%), galactose (3.4%), heptose (4.6%) and 2-keto-3-deoxy-mannosulonic acid (0.8%). Polysaccharide II was obtained in 0.8–1% yield (based on dry bacteria). It contained 99.2% mannose. With the method of Yphantis it was found that the molecular weights of polysaccharides I and II were 12400 and 10400, respectively. The difference accounted for the core oligosaccharide which was present in polysaccharide I and absent in polysaccharide II. The specific optical rotation was 43 °C for polysaccharide I and 42 °C for polysaccharide II. Both polysaccharides were permethylated. Subsequent hydrolysis, reduction and acetylation, followed by gas-liquid chromatography and mass spectrometry indicated that in both polysaccharides two-thirds of the mannose units were substituted at C-2 and one-third at C-3. These results were confirmed by periodate oxidation. From polysaccharide II nine oligosaccharides were obtained after partial acid hydrolysis by chromatography on Biogel P2, paper chromatography and paper electrophoresis of the borate complexes. The oligosaccharides were reduced with sodium borodeuterate (which labelled the reducing mannose units) and methylated. After hydrolysis, reduction and acetylation the products were analyzed by gas chromatography and mass spectrometry. It is concluded that the poIysaccharides I and II contain about 20 repeating units of α-mannosyl-1,2-α-mannosyl-1,2-α-mannose which are joined through &alph;-1,3 linkages. [ABSTRACT FROM AUTHOR]

An inhibitor from Pinus radiata was separated using paper chromatography from an acidic ether fraction of a stem tissue extract. Using electrophoresis the inhibitory activity was resolved into two parts. One part remained at the origin. The second part behaved similarly to ABA, in electrophoresis and was investigated further. The inhibitor has similar properties to ABA in electrophoresis; TLC using a number of solvent systems; UV fluorescence spectra: UV absorption; ORD spectra and gas chromatography. Final proof of the identity of the natural inhibitor as ABA was obtained by gas chromatography-mass spectrometry. [ABSTRACT FROM AUTHOR]

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Recently, it has been found that nonionic aliphatic and aromatic poly(ester sulfone)s show anode selective electrophoretic behavior, and it is shown that the electrophoresis is induced by a partial charge separation of the protic solvent at the dispersion interface. In this paper, the first example of temperature- responsive electrophoretic deposition (EPD) is reported. Electrophoresis of a nonionic sulfone-containing poly(N-isopropylacrylamide) [poly(NIPAM)] is performed above the lower critical solution temperature. The poly(NIPAM) is prepared via reversible addition--fragmentation chain transfer radical copoly merization of NIPAM with a sulfone-containing methacrylate. After EPD, adhesion of human umbilical vein endothelial cells on the deposited surfaces is also demonstrated, aiming at the subsequent temperature-sensitive detachment. [ABSTRACT FROM AUTHOR]

Contents The objective of this work was to describe the presence of osteopontin (OPN) in canine seminal plasma and sperm membranes. A pool of seminal plasma and sperm membrane extract from 30 dogs was used. Polyacrylamide electrophoresis gels were performed and the bands were transferred to nitrocellulose paper and Western blot was undertaken using an antibody anti-OPN. Two and 12 bands were marked in the seminal plasma (77.2 and 15.6 kDa) and sperm membrane extracts (70.6–26.6 kDa), respectively. However, from 12 marked bands in the sperm membrane extract, only three (46.4, 37.7 and 36.5 kDa) were strongly marked. We conclude that, seminal plasma and sperm membranes from dogs contain different isoforms of OPN; yet, further studies will be necessary to determine their function in this species. [ABSTRACT FROM AUTHOR]

Transporting microdroplets using electric fields can be accomplished with several mechanisms, the primary methods being dielectrophoresis (DEP) for electrically insulating liquids, and electrowetting on dielectric for conducting fluids. In both cases, an electric field is applied near the leading edge of the droplet using patterned electrodes, giving rise to an electrostatic pressure that induces droplet transport. This paper examines the nature of the force distribution for DEP-actuated droplets in several electrode configurations, calculated using a numerical method designed for handling jump conditions in the Poisson equation. The numerical method is described and verified by comparison with known analytical results. The net force acting upon a DEP droplet is investigated, with the effect of electrode configuration presented for several cases, demonstrating some beneficial aspects for engineering applications. [ABSTRACT FROM AUTHOR]

Art extremely simple, inexpensive, and safe method is presented, which emulates nucleic acids isolation and electrophoretic analysis as performed in a research environment, in the context of a secondary school hands-on activity. The protocol is amenable to an interdisciplinary approach, taking into consideration the electrical and chemical parameters of the electrophoretic system. Furthermore, the laboratory is framed in a more comprehensive pedagogical setting, which addresses the methodological aspects of a pivotal scientific enterprise such as the Human Genome Project. In this setting, the hands-on activity is complemented with animations, paper models, and discussions. Additionally, our results indicate that the use of borate buffer and agar-agar gels suits many of the experiments included in college-level laboratory activities, which currently make use of more expensive agarose gels and TBE or TAE buffers. [ABSTRACT FROM AUTHOR]

Protein extracts originally prepared for isozyme electrophoresis two decades ago contain surviving DNA sequences susceptible to amplification by the polymerase chain reaction (PCR). Amplification was also possible after stabilization of such extracts on filter paper and immersion under mineral oil without refrigeration. [ABSTRACT FROM AUTHOR]

Investigations were performed to study the chemical form in which nickel and cobalt are transported in sieve tubes, Ricinus communis plants were used since they allow easy collection of relatively pure phloem sap. In the experiments labelled nickel or cobalt were given to the nutrient solution. The tapped phloem exudate was separated by gel filtration on Sephadex or by paper electrophoresis. Nickel and cobalt were bound to complexing organic compounds with a molecular weight in the range of 1000- 5000. The overall charge of the nickel complex was negative, and the bulk of cobalt also appeared to complex to a compound with negative overall charge. [ABSTRACT FROM AUTHOR]

From the lipopolysaccharide of the gram-negative bacterium Rhodopseudomonas capsulata (Athiorhodaceae) a lipophilic sugar was isolated by chromatographic procedures and characterized by mass spectrometry as belonging to the group of 3-O-methyl-6-deoxy-hexoses. Demethylation showed that the parental sugar had the same properties in borate electrophoresis as rhamnose. Comparison with an authentic sample of 3-O-methyl-rhamnose in gas liquid chromatography, paper chromatography and borate electrophoresis showed that the sugar under examination is 3-O-methylrhamnose (acofriose). Investigation of its optical rotation indicates that the sugar has the L-configuration. L-Acofriose (3-O-methyl-L-rhamnose) has not hitherto been found in lipopolysaccharides of gram-negative bacteria. [ABSTRACT FROM AUTHOR]

From Escherichia coli 0124 two lipopolysaccharide preparations were obtained with phenol/water extraction and cetavlon precipitation. Polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate and chemical analysis showed that the two preparations differed only in the extent of the O-specific polysaccharide moiety. In passive haemagglutination and gel precipitation the two lipopolysaccharide preparations from E. coli 0124 and the corresponding preparations from Shigella dysenteriae type 3 reacted alike. The O-specific polysaccharide moiety was characterized with proton magnetic resonance spectroscopy, optical rotation and paper electrophoresis. The constituents were determined by gas chromatography and ion-exchange chromatography. The polysaccharide contained glucose (Glc), gatactose (Gal), galactosamine (GalN) and 4-O-(1′-carboxyethyl)-D-glucopyranose (glucolactilic acid, GIcLA) in the molar ratios of 1 : 2 : 1 : 1. Glucolactilic acid, which has a structure similar to muramic acid, was first found in Sh. dysenteriae. The polysaccharide from E. coli 0124 and oligosaccharides obtained from it by partial acid hydrolysis were subjected to methylation analysis using the method of combined gas chromatography—mass spectrometry. The results indicated that the pentasaccharide repeating unit of the polysaccharide is[This symbol cannot be presented in ASCII format] In the polysaccharide the repeating units are joined through galactofuranosidic linkages. This structure is identical with that of the somatic polysaccharide of Sh. dysenterae type 3. [ABSTRACT FROM AUTHOR]

We have analysed limit digests of mini-circles from kinetoplast DNA of Crithidia luciliae by gel electrophoresis. Endonucleases HapII and AluI cut the circles into at least 37 and 21 fragments, respectively, and leave no circles intact. In both cases the added molecular weights of the fragments, estimated from mobility in gets, exceeds 18 × 106, i.e. more than 12 times the molecular weight of the mini-circle DNA. Endonucleases HindII + III, EcoRI and HpaI cut only part of the circles. These results show that the mini-circles are heterogeneous in base sequence. Different sequence classes are present in different amounts. DNA-DNA renaturation analysis of mini-circle DNA yields a complexity of about 3 × 106, i.e. twice the molecular weight of one mini-circle. The &Deltm of native and renatured duplexes is about 1°C, showing that the sequence heterogeneity is a micro-heterogeneity. Electron microscopy, get electrophoresis and sedimentation analysis show that the circles that are not cut by endonucleases HindII + III remain catenated in very large associations. These associations lack the ‘rosette’ structures and the long edge loops characteristic of intact kinetoptast DNA. This suggests that the mini-circle classes cut by endonucleases HindII + III are present throughout the network and that the maxi-circle component of the network (see accompanying paper) is not essential to hold the network together: Prolonged electrophoresis on 1.5% or 2% agarose gels resolves the open mini-circles into three and linearized mini-circles into four bands, present in different amounts. We conclude that the mini-circles are also heterogeneous in size, the difference in size between the two extreme size classes being 4% of the contour length. Digestion with endonuclease HapII shows that at least three out of these four bands differ in sequence, Possible mechanisms that could account for the micro-heterogeneity in sequence of mini-circles are discussed. [ABSTRACT FROM AUTHOR]

Several large oligonucleotides obtained by partial digestion of tRNAIIArg from brewers' yeast with ribonnclease T1 have been isolated and their sequences have been established. These results and those described in the preceding paper permitted the derivation of the complete primary structure of this tRNA. [ABSTRACT FROM AUTHOR]