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Techniques used in the quantitative evaluation of thin-layer chromatograms are compared. The quantitation of tubular thin-layer chromatograms by means of vapor-phase detectors is emphasized, and typical examples of the use of this method are outlined. Applications of tubular thin-layer chromatography (TTLC) in the quantitative analysis of fish liver oils are described.
The raw materials of retinol acetate and retinol palmitate were examined for the preparation of the "Retinol Acetate Reference Standard for Thin-layer Chromatography" and "Retinol Palmitate Reference Standard for Thin-layer Chromatography", respectively. Analytical data obtained were as follows: thin-layer chromatography, no impurities were detected in retinol acetate and one impurities was detected in retinol palmitate; The Rf values of retinol acetate and retinol palmitate were consistent with those of Reference Standards (Control 713), respectively; ultraviolet spectrum, lambda max = 326 approximately 327 nm; relative extinction, within the range reported in JPXI; weight variation of capsules, retinol acetate 224.0 +/- 15.5 mg (RSD 6.9%), retinol palmitate 222.0 +/- 13.8 mg (RSD 6.2%); assay, retinol acetate 57000 I.U./g, retinol palmitate 57000 I.U./g. Based on the above results, these raw materials were authorized to be the Reference Standards of the National Institute of Hygienic Sciences.
A stairlike colloidal crystal thin film composed of poly(styrene-methyl methacrylate-acrylic acid) (P(St-MMA-AA)) monodispersed colloids was fabricated on an inclined silicon substrate. Different bright colors were observed on the various parts of the film with different layers as white light irradiated perpendicularly on it. The relationship between the colors and layers of the film was investigated and discussed according to the principle of thin film interference. On the basis of the phenomenon of thin film interference, a one-layer colloidal film having uniform color was researched and it would display diverse colors before and after swollen by styrene (St). A circular stairlike colloidal film was achieved to mimic the colors of the peacock tail feather.
Birefringence of the I-band of glycerinated myofibrils of the walking legs of the crab, Plagusia dentipes was examined by rectified polarization optics. The coefficient of birefringence of the I-band was estimated to be 1.64 X 10(-3), which attained about 60% of the birefringence of the H-zone. The number ratio of thin filaments to thick filaments in the A-band was six according to electron microscopy and the spacing between neighbouring thick filaments was about 56 nm according to X-ray diffraction. From these values, the protein concentration in the I-band was estimated to be 91 mg/ml. Thus, the birefringence of the I-band was found to be of the same order as the birefringence of the reconstituted thin filaments oriented by flow at the same protein concentration. The ratio of protein concentration in the I-band to that in the H-zone was determined by interferometry. The ratio of birefringence of the I-band to that of the H-zone per unit protein concentration was found to be about 0.9, which was comparable to the ratio of birefringence of the thin filaments and thick filaments in solution. The imbibition experiment showed that 70% of the total birefringence of the I-band is form birefringence and remaining 30% comes from intrinsic birefringence.
In the heart, the contractile apparatus is adapted to the specific demands of the organ for continuous rhythmic contraction. The specialized contractile properties of heart muscle are attributable to the expression of cardiac-specific isoforms of contractile proteins. This review describes the isoforms of the thin filament proteins actin and tropomyosin and the three troponin subunits found in human heart muscle, how the isoform profiles of these proteins change during development and disease, and the possible functional consequences of these changes. During development of the heart, there is a distinctive switch of isoform expression at or shortly after birth; however, during adult life, thin filament protein isoform composition seems to be stable despite protein turnover rates of 3 to 10 days. The pattern of isoforms of actin, tropomyosin, troponin I, troponin C, and troponin T is not affected by aging or heart disease (ischemia and dilated cardiomyopathy). The evidence for proteolysis of thin filament proteins in situ during ischemia and stunning is evaluated, and it is concluded that C-terminal cleavage of troponin I is a feature of irreversibly injured myocardium but may not play a role in reversible stunning.
The acrylic denture bases are most commonly used as compared with metallic denture bases at present. For this reason, it is due to many excellent properties, for example, simple processing, easy repair, cheapness and so on. But an inherent disadvantage is liability of an acrylic denture base to make thick so as to maintain stiffness and strength and it makes patients uncomfortable. Therefore, the purpose of this paper is to make the palatal region of the upper complete denture thin with about 0.7 mm in thickness, and to keep the same mechanical properties as the normal resin dentures using the composites materials with carbon cloth. Tensils test of the plate test-piece and uniform bending test of the upper complete denture with steel wings were respectively performed. The results obtained in this investigation are as follows: 1) The acrylic composites reinforced with carbon cloth have shown the superior mechanical properties to be compared with the acrylic resin to be generally used. 2) The thickness of the reinforced thin denture is decreased to 0.7 mm (its thickness is 60% of the normal thickness of the one), nevertheless, the stiffness and strength are increased with the using of the composite materials. 3) The region of highest surface tensile stress in the denture was on the polished surface of the palatal aspect of the denture in the area immediately behind the anteriors, but at this region, the strain of the reinforced thin denture base decreased its strain 10% in comparison with the non-reinforced normal thick one.
In this paper, succeeding the study of the part 1 on the thinning of the upper acrylic resin complete denture with the reinforced palate, it was investigated to keep the same stiffness and strength as the normal resin dentures, and to make the patient comfortable. Besides, many different palate forms exist in the patient's mouth in clinical cases, and so, influence of these forms on the thin plate dentures comes into question. Therefore, 3 types of the palate forms (the standard shape, the extremely large torus and the generally shallow shape) were established, and then the flexural stiffness and strength, and the deformation of the denture bases were scrutinized in this paper. The results obtained in this investigation are as follows: 1) The maxillary torus with sheer bulk had little influence on the flexural stiffness and strength. But, about the generally shallow-shaped denture bases, the mechanical properties dropped a little as compared the normal resin denture bases. The reinforced thin denture bases of which thickness was 60% of the normal one, showed the excellent mechanical properties in spite of the difference of the palate forms. 2) In the upper complete denture base, in spite of the palate forms, anteriority and posteriority of the one were deformed against the load direction around the frontal section through the bilateral canines, and the bilateral ridges of the one were deformed to the load direction around the midline of the denture base. The deformation was extremely decreased by not only the palate but also the whole of the denture base as the reinforced one.
Methods of thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) were developed for the determination of estrogens and antithyroid drugs in extracts of animal tissues. TLC proved to be suitable for quantities in the range of 200-2000 ng, with a detection limit of 50-200 ng, HPTLC in the range of 10-200 ng, showing calibration curves of good linearity even in extracts. By HPTLC better detection limits, better separation and faster ascending could be achieved than by TLC.
A rapid, non-hydrolytic thin-film fluorescence scanning method is described for the quantitation of adriamycin and metabolites in tissues. Adriamycin, with daunomycin added as the internal standard, was extracted from tissue homogenate which contained 500 micrograms of oxalic acid, with ice-cold 0.5 N hydrochloric acid--85% isopropanol, separated by thin-layer chromatography, and quantitated in situ via a fluorescence scanning technique. This method has a sensitivity to 0.05 microgram per gram of tissue.
An analytical scheme composed of one normal-phase thin-layer chromatographic (TLC) method, one reversed-phase thin-layer chromatographic (RPTLC) method, and sequential analyte detection through four stages of color reactions is described. Eighty-one basic or neutral drugs were analyzed with this scheme and seventy-four were uniquely characterized with 95% confidence. Six of the remaining seven formed three unresolved pairs. The scheme was evaluated by mean list length analysis and shown to offer analyte resolution similar to that of a scheme of TLC and gas chromatography (GC) with nonspecific detection. Nine out of ten unknowns from the field of eighty-one drugs were uniquely identified with 95% confidence by the TLC/RPTLC scheme. The tenth unknown was not completely resolved from its isomer, but was statistically the more probable candidate.
A new track etch autoradiographic technique for quantitating boron-10 containing compounds used for neutron capture therapy is described. Instead of applying solutions of Cs2B12H11SH and its oxidation products directly to solid-state nuclear track detectors, diethylaminoethyl cellulose thin layer chromatography (TLC) plates are utilized as sample matrices. The plates are juxtaposed with Lexan polycarbonate detectors and irradiated in a beam of thermal neutrons. The detectors are then chemically etched, and the resultant tracks counted with an optoelectronic image analyzer. Sensitivity to boron-10 in solution reaches the 1 pg/microliter level, or 1 ppb. In heparinized blood samples, 100 pg boron-10/microliter are detected. This TLC matrix method has the advantage that sample plates can be reanalyzed under different reactor conditions to optimize detector response to the boron-10 carrier material. Track etch/TLC allows quantitation of the purity of boron neutron capture therapy compounds by utilizing the above method with TLC plates developed in solvent systems that resolve Cs2B12H11SH and its oxidative analogs. Detectors irradiated in juxtaposition to the thin layer chromatograms are chemically etched, and the tracks are counted in the sample lane from the origin of the plate to the solvent front. A graphic depiction of the number of tracks per field yields a quantitative analysis of compound purity.
A previous formulation of the field correlation function G1(tau) of light quasielastically scattered from suspensions of rigid rods undergoing anisotropic translational as well as rotational diffusion (T. Maeda and S. Fujime, Macromolecules 17 (1984) 1157) was extended to the cases of suspensions of cylinders (length L and radius R), ellipsoids and ellipsoidal shells of revolution (x2/b2 + y2/b2 + z2/a2 = 1). The present formulation includes that for suspensions of rigid rods in the limit of KR 1 or in the limit of b/a 1 and Kb 1 (an extremely prolate ellipsoid), and also that for suspensions of discs in the limit of KL 1 or in the limit of b/a 1 and Ka 1 (an extremely oblate ellipsoid), where K is the length of the scattering vector. Explicit forms of G1(tau), of the first cumulant Gamma of G1(tau) and of the dynamic form factors will be given, and numerical methods suitable for computation of dynamic form factors will be discussed. The present results can be applied to the analysis of experimental data for dilute suspensions of thin rods and thin discs. When the situation is favorable, our method can provide transport coefficients D1, D3, and Theta from dynamic light-scattering data only, where D(1) and D(3) are, respectively, the translational diffusion coefficients parallel with the x (y) and z axes, and Theta the rotational diffusion coefficient around the x (y) axis.
As functional metal complexes, copper phthalocyanine (CuPc) and Cobalt (II) meso-tetraphenylporphyrin (CoTPP) were chosen to prepare metal complex/polymer hybrid thin films which were prepared by metal complex sublimation and reactive monomer evaporation onto the glass substrate in the bell jar reactor in vacuum conditions. The polarized transmission micrograph images show that the film deposited at 80 degrees C contains uniformly dispersed tiny grains and the film deposited at 30 degrees C is amorphous and homogeneous. As the deposition rate increases, the crystalline clusters were found and were dispersed uniformly. Those crystalline clusters are not to be developed by recrystallization process. Deposited metal complex/acrylate hybrid thin films were in situ photopolymerized. The kinetics of photopolymerization was investigated by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The thickness of the films was about 200 nm. The reactive monomer acts as a solvent to avoid the recrystallization of metal complexes and to have two-compositional continuous phase. The percent of metal complex can be adjusted up to 60% by controlling the metal complex sublimation rate. A good achievement in the uniformity and continuity of the film matrix has been made and the recrystallization of metal complex in the hybrid films has not been observed.
Troponin C (TnC) is the Ca(2+)-sensing subunit of troponin responsible for initiating the cascade of events resulting in contraction of striated muscle. This protein can be readily extracted from myofibrils with low-ionic-strength EDTA-containing buffers. The properties of TnC extraction have not been characterized at the structural level, nor have the interactions of TnC with the native myofibrillar thin filament been studied. To address these issues, fluorescein-labeled TnC, in conjunction with high-resolution digital fluorescence microscopy, was used to characterize TnC binding to myofibrils and to determine the randomness of TnC extraction. Fluorescein-5-maleimide TnC (F5M TnC) retained biological activity, as evidenced by reconstitution of Ca(2+)-dependent ATPase activity in extracted myofibrils and binding to TnI in a Ca(2+)-sensitive manner. The binding of F5M TnC to highly extracted myofibrils at low Ca2+ was restricted to the overlap region under rigor conditions, and the location of binding was not influenced by F5M TnC concentration. The addition of myosin subfragment 1 to occupy all actin sites resulted in F5M TnC being bound in both the overlap and nonoverlap regions. However, very little F5M TnC was bound to myofibrils under relaxing conditions. These results suggest that strong binding of myosin heads enhances TnC binding. At high Ca2+, the pattern of F5M TnC binding was concentration dependent: binding was restricted to the overlap region at low F5M TnC concentration, whereas the binding propagated into the nonoverlap region at higher levels. Analysis of fluorescence intensity showed the greatest binding of F5M TnC at high Ca2+ with S1, and these conditions were used to characterize partially TnC-extracted myofibrils. Comparison of partially extracted myofibrils showed that low levels of extraction were associated with greater F5M TnC being bound in the nonoverlap region than in the overlap region relative to higher levels of extraction. These results show that TnC extraction is not random along the length of the thin filament, but occurs more readily in the nonoverlap region. This observation, in conjunction with the influence of rigor heads on the pattern of F5M TnC binding, suggests that strong myosin binding to actin stabilizes TnC binding at low Ca2+.
The glass transition temperature T(g) and the temperature T(alpha) corresponding to the peak in the dielectric loss due to the alpha process have been simultaneously determined as functions of film thickness d through dielectric measurements for polystyrene thin films supported on glass substrate. The dielectric loss peaks have also been investigated as functions of frequency for a given temperature. A decrease in T(g) was observed with decreasing film thickness, while T(alpha) was found to remain almost constant for d>d(c) and to decrease drastically with decreasing d for d<d(c). Here, d(c) is a critical thickness dependent on molecular weight. The relaxation time tau(alpha) of the alpha process, which was measured as the frequency at which the dielectric loss realizes its peak value at a given temperature, was found to have a d dependence similar to that of T(alpha). The relaxation function for the alpha process was obtained by using the observed frequency dependence of the peak profile of the dielectric loss. The exponent beta(KWW), which was obtained from the relaxation functions, decreases as thickness decreases. This suggests that the distribution of relaxation times for the alpha process broadens with decreasing thickness. The thickness dependence of T(g) is directly related to the distribution of relaxation times for the alpha process, not to the relaxation time itself. The value of the thermal expansion coefficient normal to the film surface was found to increase with decreasing film thickness below T(g), but to decrease with decreasing film thickness above T(g). These experimental results are discussed in the context of a three-layer model in which within thin films there are three layers with different mobilities and glass transition temperatures.
Thin oxide films grown on metal substrates are widely used in surface science to model bulk oxides, assuming their chemical and electronic properties to be similar. In some cases, however, this might not be justified as the present scanning tunneling microscopy studies demonstrate for Au atoms on a thin alumina film on NiAl(110). Au atoms were evaporated onto the oxide film at a sample temperature of approximately 10 K. At low coverage, this leads to the formation of one-dimensional clusters with unusually large Au-Au distances of 5.6-6.0 A. A direct interaction between the Au atoms can be excluded, and a substrate-mediated mechanism is supposed instead. This assumption is strengthened by the finding that the Au chains exhibit a preferential orientation: They are almost aligned with the [001] direction of the NiAl(110) substrate, clearly indicating that the metal substrate participates in the binding of the Au atoms.
The exact measurement of the thickness of semi-thin and ultra-thin sections is of importance for some stereological methods. Although section thickness can be measured with great precision and accuracy using suitable microinterferometers, such instruments are expensive and not easily available to many laboratories. This paper describes a simple method of measuring the thickness of sections actually used for stereological counting procedures. It involves the division of any given section into two portions, one of which is used for the counting procedures. The other portion is re-embedded and re-sectioned through its thickness making it a simple task to measure its thickness.
The spatial relationships between Lys-61, Cys-374 on actin or SH1 on myosin subfragment-1 (S1) and Cys-190 on tropomyosin or Cys-133 on troponin-I (TnI) in a reconstituted thin filament were studied by fluorescence resonance energy transfer. 5-(2-Iodoacetylaminoethyl)aminonaphthalene 1-sulfonic acid (IAEDANS) attached to Lys-190 on tropomyosin or to Cys-133 on TnI was used as a donor. Fluorescein 5-isothiocyanate (FITC) attached to Lys-61 or 5-(iodoacetoamido)fluorescein (IAF) attached to Cys-374 on actin and 4-dimethylaminophenyl-azophenyl 4'-maleimide (DABMI) attached to SH1 on S1 were used as an acceptor. The transfer efficiency between AEDANS attached to Cys-190 on tropomyosin and FITC attached to Lys-61 on actin was 0.42 in the absence of troponin, 0.46 in the presence of troponin and Ca2+ and 0.55 in the presence of troponin and absence of Ca2+. The corresponding distances between the probes were calculated to be 4.7 nm, 4.6 nm and 4.3 nm respectively, assuming a random orientation factor K2 = 2/3. A large difference in the transfer efficiency from AEDANS attached to Cys-133 on TnI to FITC attached to Lys-61 on actin was observed between in the presence (0.52) and absence (0.70) of Ca2+. The corresponding distances between the probes were calculated to be 4.5 nm in the presence of Ca2+ and 3.9 nm in the absence of Ca2+. The distance between Cys-190 on tropomyosin and Cys-374 on actin was measured to be 5.1 nm and the transfer efficiency (0.35) did not change upon addition of troponin whether Ca2+ is present or not, in agreement with the previous report [Tao, T., Lamkin, M. & Lehrer, S. S. (1983) Biochemistry 22, 3059-3064]. The distance between Cys-133 on TnI and Cys-374 on actin was measured to be 4.4 nm. No detectable change in transfer efficiency (0.58) was observed between values in the presence and absence of Ca2+. These results suggest that a relative movement of the two domains of actin monomer in a reconstituted thin filament occurs in response to a change in Ca2+ concentration. The transfer efficiencies between DABMI attached to SH1 on S1 and AEDANS attached to Cys-190 on tropomyosin or Cys-133 on TnI were too small (less than 2%) for an accurate estimation of the distances, suggesting the distances are longer than 7.3 nm.