Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.10.2 (focal adhesion kinase)
44,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Electron microscopic visualization of molecular hybrids formed in situ is feasible at the present time. It can be accomplished by two alternative approaches. In one, the in situ hybridization is carried out on ultrathin sections of target embedded in glycol methacrylate. In the other, whole cells are used for hybridization and they are subsequently prepared for electron microscopy. The choice of the method to be adopted depends on the type of target tissue. When there is a choice, the second approach seems preferable. Some of the important technical steps in the hybridization procedure, such as DNA denaturation in ultrathin sections, have been discussed and attention has been drawn to practical problems that may arise during the preparatory steps. Our light microscope experiments demonstrate that preparations made after glutaraldehyde fixation have a lower hybridization efficiency than those fixed with 3 : 1 methanol-acetic acid. Attempts are therefore being made to explore the possibility of using methanol-acetic acid for electron microscope in situ hybridization. First results of straight-forward fixation show that the preservation of nuclear structure may be fairly satisfactory for the purpose. However, the cumultative effects of subsequent treatments in the procedure still remain to be examined. For electron microscope autoradiograph (EM ARG) of hybridized preparations, the most suitable emulsion at present appears to be Ilford L4. Various factors conductive to optimum resolution consistent with maximum efficiency in this emulsion have been pointed out. Practical problems that may arise in autoradiographs of hybridized preparations such as background and variation of grain density in adjacent sections have also been considered.
...
PMID:Molecular hybridization of RNA and DNA in situ" visualization at the electron microscope level. 94 30

To obtain insight into the identity of chemicals associated with the mutagenicity of United States National Institute of Standards and Technology (NIST) Standard Reference Materials SRM 1649 (urban dust) and SRM 1650 (diesel particulate), parallel mutagenicity tests and chemical analyses were performed on dichloromethane and sequential organic extracts of these samples. SRM 1649 and 1650 were sequentially extracted with five organic solvents of increasing polarity, in order to partition mutagenic components into discrete fractions. The solvents (with associated polarity index) were as follows: (1) hexane (0.0); (2) hexane:diethyl ether 9:1 (0.29); (3) hexane:diethyl ether 1:1 (1.45); (4) diethyl ether (2.9); (5) methanol (6.6). 0.9270 g of SRM 1649, and 0.0510 g of SRM 1650 were each extracted three times with 8 ml of each of the solvents, the three aliquots were pooled, and analysed for target organics or solvent-exchanged into DMSO for mutagenicity testing in Salmonella typhimurium strains TA98 and TA100. The dichloromethane extracts of SRM 1649 and SRM 1650 contained direct-acting mutagens in Salmonella strains TA98 and TA100; SRM 1650 was significantly more potent than SRM 1649 in either strain. Addition of S9 caused a large decrease in mutagenicity of each extract, although SRM 1650 remained more potent. An interesting pattern of mutagenicity was observed for the sequential extracts of SRM 1649 and SRM 1650: the mutagenic potency of SRM 1649 extracts increased with increasing polarity of the extraction solvent while the response of the SRM 1650 extracts was the opposite. This suggests that the direct-acting mutagens in SRM 1650 are unlike those in SRM 1649. The response, though diminished, was largely unchanged when S9 was included in the test mixture. Chemical analyses on the various extracts were performed using a Hewlett-Packard model 5890 gas chromatograph equipped with a model 5970B mass selective detector (GC-MSD), and a 0.3 microns film thickness cross-linked methyl silicone capillary column (HP 1909A-101). Selected ion monitoring (SIM) methods were used to analyze for 105 target compounds including PAHs and nitro-PAHs. Chemical analysis of the dichloromethane extracts of SRM 1649 and SRM 1650 identified three main classes of compounds: polyaromatic hydrocarbons (PAH), nitro-polyaromatic hydrocarbons (NO2-PAHs) and heterocyclics. The concentration of target compounds and the proportion of nitro-PAHs and heterocyclic compounds were considerably greater in SRM 1650 than in SRM 1649, consistent with the observed differences in their mutagenic potency. However, the different responses of the dichloromethane extracts in TA98 and TA100 suggest the presence of different (unidentified) compounds.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Mutagenicity and chemical analysis of sequential organic extracts of airborne particulates. 137 Jan

A method is described for detection of nonoxynol in condoms, based on methanol-water extraction followed by reverse-phase high-performance liquid chromatography. Using this method, we found that approximately 50% of the nonionic surfactant lubricant nonoxynol migrated into elastomers (rubber latex), resulting in a concentration of nonoxynol insufficient to inhibit human immunodeficiency virus (HIV) (less than 0.05%). In order to minimize the risk of sexual transmission of HIV, and to ensure spermicidal effect and optimal rubber properties, the concentration of nonoxynol in condoms, therefore, should either be increased, or nonoxynol should be packed separately. Further studies are needed to clarify and determine the solubility and migration of nonoxynols into elastomers.
Int J STD AIDS 1990 Sep
PMID:Evaluation of the amount of nonoxynol available in condoms for the inhibition of HIV using a method based on HPLC. 196 70

Biochemical analysis of the kinetics of assembly of two cytoplasmic plaque proteins of the desmosome, desmoplakins I (250,000 Mr) and II (215,000 Mr), in Madin-Darby canine kidney (MDCK) epithelial cells, demonstrated that these proteins exist in a soluble and insoluble pool, as defined by their extract ability in a Triton X-100 high salt buffer (CSK buffer). Upon cell-cell contact, there is a rapid increase in the capacity of the insoluble pool at the expense of the soluble pool; subsequently, the insoluble pool is stabilized, while proteins remaining in the soluble pool continue to be degraded rapidly (Pasdar, M., and W. J. Nelson. 1988. J. Cell Biol. 106:677-685). In this paper, we have sought to determine the spatial distribution of the soluble and insoluble pools of desmoplakins I and II, and their organization in the absence and presence of cell-cell contact by using differential extraction procedures and indirect immunofluorescence microscopy. In the absence of cell-cell contact, two morphologically and spatially distinct patterns of staining of desmoplakins I and II were observed: a pattern of discrete spots in the cytoplasm and perinuclear region, which is insoluble in CSK buffer; and a pattern of diffuse perinuclear staining, which is soluble in CSK buffer, but which is preserved when cells are fixed in 100% methanol at -20 degrees C. Upon cell-cell contact, in the absence or presence of protein synthesis, the punctate staining pattern of desmoplakins I and II is cleared rapidly and efficiently from the cytoplasm to the plasma membrane in areas of cell-cell contact (less than 180 min). The distribution of the diffuse perinuclear staining pattern remains relatively unchanged and becomes the principal form of desmoplakins I and II in the cytoplasm 180 min after induction of cell-cell contact. Thereafter, the relative intensity of staining of the diffuse pattern gradually diminishes and is completely absent 2-3 d after induction of cell-cell contact. Significantly, double immunofluorescence shows that during desmosome assembly on the plasma membrane both staining patterns coincide with a subpopulation of cytokeratin intermediate filaments. Taken together with the preceding biochemical analysis, we suggest that the assembly of desmoplakins I and II in MDCK epithelial cells is regulated at three discrete stages during the formation of desmosomes.
...
PMID:Kinetics of desmosome assembly in Madin-Darby canine kidney epithelial cells: temporal and spatial regulation of desmoplakin organization and stabilization upon cell-cell contact. II. Morphological analysis. 327 50

Chemical fractions from 4 shale oils including one produced in an above-ground retort (Paraho), 2 produced below ground by in situ method (Occidental and Geokinetics), and 1 produced by a simulated modified in situ process (Livermore), were tested for mutagenicity against Salmonella typhimurium TA98 in the Ames assay system. Their mutagenic activities were compared with 2 other complex materials: a high-boiling coal distillate (The Solvent Refined Coal Process I (SRC II) heavy distillate), and a crude petroleum (Prudhoe Bay). Each material was fractionated by Sephadex LH-20 partition chromatography and by acid-base solvent extraction to provide chemical fractions for bioassay. Mutagenic activity was detected in the coal liquid (and their fractions), but not in the natural crude oil nor in any of its fractions. The basic and tar fractions derived by solvent extraction, and the LH-20 methanol fractions contained most of the mutagenic activity recovered from the unfractionated material. The heavy distillate was approx. 10 times more active in the Ames assay than the most mutagenically active shale oil. The most mutagenically active of the shale oils was about 10 times more active than the least active shale oil.
...
PMID:Comparison of the mutagenicities of fossil fuels. 703 38

An automated gas chromatographic method for the simultaneous determination of cholesterol, alpha-tocopherol and alpha-tocopheryl acetate in edible oils and fats without derivatization is reported. Interferences from lipid material are avoided by using a continuous system to transesterify triglycerides with potassium methylate in methanol. The precision of the method is 1.9, 2.2 and 3.1% for cholesterol, alpha-tocopherol and alpha-tocopheryl acetate, respectively. The proposed methods was validated by analysing a standard reference material of coconut oil (SRM 1563-2) with good results. The method features a high throughput, minimal sample handling and analyte specificity (lipid material does not interfere).
...
PMID:Gas chromatographic determination of cholesterol and tocopherols in edible oils and fats with automatic removal of interfering triglycerides. 858 31

The photodynamic properties and biodistribution pattern of zinc dodecafluoro-4-sulphophthalocyanine (ZnPcF12S1), zinc hexadecafluorophthalocyanine (ZnPcF16) and zinc phthalocyanine (ZnPc) were evaluated in the murine EMT-6 tumour model. All 3 dyes were formulated as a Cremophor oil-water emulsion after initial solubilization in methanol, acetone and pyridine, respectively. Comparison of their phototoxicity after in vitro incubation with EMT-6 cells and exposure to various fluences of red light showed that ZnPcF12S1 is about 50 times more active than ZnPcF16, reflecting better cell-penetrating properties. Solubilisation of ZnPc in 1-methyl-2-pyrrolidinone prior to formulation resulted in loss of photoactivity upon dilution in serum due to precipitation of the dye in the aqueous environment. In contrast, initial solubilisation in pyridine likely forms a ZnPc-pyridinium salt, and this preparation was 6 times more phototoxic than ZnPcF12S1. In vivo comparison of monosulphonated ZnPcF12S1 with perfluorinated ZnPcF16 showed improved pharmacokinetics in mice, including lower liver and spleen retentions and higher tumour-to-non-target tissue ratios. However, photodynamic therapy (PDT) of the EMT-6 tumour in BALB/c mice with red light, 24 or 48 hr post-injection of 1 micromol x kg(-1) of ZnPcF12S1 induced mortality. Lowering the drug and/or light dose or extending the time interval between drug administration and irradiation to 72 hr avoided adverse effects but also resulted in poor tumour response. The best tumour control (25% of animals) was obtained at 0.1 micromol x kg(-1) and a fluence of 400 J x cm(-2) at 24 hr post-injection. In contrast, ZnPcF16 required a 20-fold higher drug dose to induce a similar tumour response. The systemic shock following PDT with the amphiphilic ZnPcF12S1 likely results from extensive cellular effects.
...
PMID:Photodynamic activities and biodistribution of fluorinated zinc phthalocyanine derivatives in the murine EMT-6 tumour model. 921 35

The change in amino acid enrichment, an indicator of a change in protein synthesis and/or degradation, is usually measured using gas chromatography-mass spectrometry and/or (GC-combustion) isotope ratio mass spectrometry. Unfortunately, often a complex and sensitive derivatization procedure and/or a large amount of sample is required. Also, these techniques are less suited to study intermediary metabolism, in which the simultaneous application (and thus measurement) of multiple amino acid tracers is preferred. Alternatively, in this study the possibilities of the coupling of liquid chromatography and mass spectrometry were explored, resulting in the measurement of both the concentration and isotope enrichment of o-phthaldialdehyde (OPA)-derivatizated plasma amino acids in one run. This was achieved by the injection of OPA-derivatizated amino acids into an automated HPLC system. After the elution of buffer salts and reagent excess to drain using column switching, the column effluent was directed via a fluorescence detector into a Thermoquest Model LCQ benchtop LC-MS. Mass spectrometric measurements were performed in "zoom-scan" mode, employing multiple scan events if the target components were not baseline separated. Best signal-to-noise ratio's were obtained using the LCQ's electrospray probe in the negative mode. Still, when working under standard conditions the total ion current of OPA-amino acid derivatives eluting at the beginning of the chromatogram (e.g., citrulline, arginine and glycine) was by a factor of 5 lower, compared to components eluting in the last part of the chromatogram (leucine, valine, and ornithine). These differences could be minimized by increasing the temperature of the heated capillary to 260 degrees C and by applying 5% collision energy (between the skimmer and the first octapole) to the first eluting components. A further improvement could not be obtained by the addition of makeup liquids like ammonia, acetic acid, methanol, or acetonitrile (up to 25% of column effluent flow). Considering these results and the fact that the first eluting amino acid derivatives are the most polar ones, we hypothesized that hydration of these components interferes with the ionization process. A linear calibration curve was obtained for both fluorescent response and total ion current (TIC) for all amino acids in the range from 5 to 1000 pmol per injection. The coefficient of variation of the fluorescent response was typically on the order of 1-4%, for the TIC this was between 4 and 9%. However, measurement of isotope ratios requires not only the determination of the area of the base peak, but also of the area of the (enriched) isotopomeric peak(s), having a much lower abundance. Therefore, isotope ratio measurements require the injection of at least 25 pmol of the amino acid derivative of interest (except for ARG 50 pmol) to obtain true ratio's. The accuracy of the isotope enrichment measurement was determined by the injection of a standard containing all major physiological amino acids (400 pmol each) and a standard at physiological concentrations (ranging from 50 pmol (CIT) to 350 pmol (VAL). Standard deviation of the isotopic ratios ranged from 0.1 to 0. 5% for the high (400 pmol) standards and from 0.2 to 0.8% for the low (physiological) standard, which is comparable with GC-MS. A plot of the results against the theoretical values gave a linear curve for all isotopes studied (R2 ranged from 0.9984 to 0.9997). However, the [1-13C]-enriched amino acids measured (LEU, GLY, and VAL) gave a closer agreement to the expected values as was found for [ureido-13C-5,5-2H2]-enriched citrulline and [guanidino-15N2]-enriched arginine. We could not determine whether this was due to the measurement procedure itself or resulting from an instability of the tracers in solution. Nevertheless, the results were reproducible and the theoretical value could be calculated using the tangent of the enrichment curves. (ABSTRACT TRUNCATED)
...
PMID:Determination of amino acid isotope enrichment using liquid chromatography-mass spectrometry. 1036 Sep 99

This work describes the unambiguous evaluation of the presence of oleuropein in virgin olive oils by ionspray tandem mass spectrometry (ISI-MS/MS). The oil samples obtained from different cultivars, such as Carolea, Cassanese, Coratina, Dolce di Rossano, Roggianella, and Tonda di Strongoli, grown in different geographical areas of Calabria, Italy, have shown an average content of oleuropein ranging from 1 ppb to 11 ppm. Commercial virgin oil samples, blended in some cases, contain significant amounts of this pharmacologically important antioxidant. The MS/MS methodology was applied in a triple-quadrupole instrument, through continuous scanning of the third analyzer to detect oleuropein in methanol extracts and in selected ion monitoring (SRM) for its quantitative assay.
...
PMID:Quantitation of oleuropein in virgin olive oil by ionspray mass spectrometry-selected reaction monitoring. 1055 83

The crystal structure of the title compound, C(16)H(16)N(3)O(3)(+). Cl(-).CH(4)O (WHI-P131, an inhibitor of Janus kinase 3), contains four hydrogen bonds. There are two hydrogen bonds within the asymmetric unit, i.e. interactions between WHI-P131 OH and Cl(-), and between methanol and Cl(-). There is a third interaction between WHI-P131 NH and Cl(-) (related by a 2(1) screw) and a fourth between WHI-P131 NH and methanol (related by an n-glide). The hydrogen-bond pattern for these interactions can be described by the first-level hydrogen-bond graph-set notation D(1)(1)(2)D(1)(1)(2)D(1)(1)(2)D(1)(1)(2). The second-level graph-set notation (for combinations of two hydrogen bonds) was determined to be D(1)(2)(3)D(1)(2)(3)D(2)(2)(4)D(2)(2)(9)D(2)(2)(14)C(1)(2)(9).
...
PMID:An inhibitor of Janus kinase 3:4-(4-hydroxyphenylamino)-6, 7-dimethoxyquinazolin-1-ium chloride methanol solvate. 1102 27


1 2 3 4 5 6 7 8 9 Next >>

---