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PubMed2001

Evaluation of guideline quality using GEM-Q.

A variety of rating instruments that evaluate the quality of practice guidelines have been published. Application of these instruments can be difficult and time-consuming. In a literature review, we identified two evaluation instruments that are comprehensive, have clearly defined constructs, and have undergone validation/testing-the Guidelines Quality Assessment Questionnaire (GQAQ) and the Appraisal Instrument for Clinical Guidelines (AICG). Overall, the AICG is more comprehensive. The AICG addresses the implementability of a guideline, which is not evaluated by the GQAQ. However, the GQAQ is more amenable to computerization. GEM-Q is a Guideline Elements Model (GEM)-derived application intended to facilitate automated evaluation of guideline quality using one of the published instruments. To develop GEM-Q, various items in the GQAQ were mapped to corresponding elements in the GEM hierarchy and a customized XSL stylesheet was designed based on this mapping. GEM-Q selectively extracts text components of the guideline relevant to quality evaluation and displays the results in HTML format. GEM-Q was applied to a set of six guidelines to test its reliability. It ranked two guidelines as of "good" quality, two as "intermediate", and two as "poor". In all six instances, GEM-Q ranked guidelines in the same order of quality as the experts who validated the GQAQ. This work demonstrates the feasibility of developing an application to facilitate automated guideline quality evaluation.

Evaluation Studies as Topic↗
PubMed2002

Clonality analysis of follicular lymphoma using laser capture microdissection method.

Whether a common and a single clone present, or not, among follicles of follicular lymphoma (FL) was examined in 12 cases with FL. Histologic grade was I in 6 cases, II in 3, and III in 3. DNA was selectively extracted from the neoplastic follicles of paraffin-embedded samples with use of laser capture microdissection method, and used for PCR-based analysis of rearrangement of immunoglobulin heavy chain variable region gene. Three different follicles in each case of FL were microdissected. Semi-nested PCR was performed using two sets of primers (Fr2A and Fr3A). In PCR with Fr2A primers, nine of 12 cases showed a common band among neoplastic follicles. The remaining three cases showed no PCR products. With Fr3A primers, eight of 12 cases showed a common band among follicles of the same case. The other four cases showed oligoclonal bands, among them presence of a common band was difficult to assess. Oligoclonal bands were more frequently observed in PCR with Fr3A than that with Fr2A and in grade I or II than in grade III cases. In total, 11 of 12 cases showed a common band in PCR with either Fr2A or Fr3A primers. In two cases, DNA extracted from whole section was amplified with both Fr2A and Fr3A or only Fr3A primers, showing smear or oligoclonal bands. These results showed the presence of a single clone of cells in neoplastic follicles of FL and the usefulness of PCR-based rearrangement analysis of immunoglobulin heavy chain gene combined with microdissection methods for differential diagnosis of FL from follicular hyperplasia.

Adult↗
PubMed2002

[Technology and analysis of Ginkgo tincture].

The article deals with the production of the tincture of Ginkgo leaves while selecting extractant, the size of particles in a raw material, and the method of extraction. The optimal concentration of the extract was established by experiment and was the following: ethanol of 70 percent (V/V), the particles size 2-3 mm, the production method percolation, and the flow speed of tincture 0.5 ml/min. The tinctura was analyzed at determination of the sum of flavonoids in terms of quercetin, dry residue, the concentration of ethanol, density, refraction index, heavy metals and microbe pollution. The stability of the tincture and its expiry date were fixed.

Chromatography, Thin Layer↗
PubMed1992

Membrane insertion of the mannitol permease of Escherichia coli occurs under conditions of impaired SecA function.

The membrane insertion of the mannitol permease (MtlA protein) of Escherichia coli, a polytopic cytoplasmic membrane protein possessing an uncleaved amphiphilic signal sequence, was studied using a cell-free protein synthesis system. The MtlA protein synthesized in the presence of inside-out cytoplasmic membrane vesicles was shown to insert into the membranes based on the following criteria: (a) co-sedimentation of the majority of the MtlA protein with the vesicles; (b) selective extraction of the membrane-associated MtlA by doxycholate but not by urea treatment; and (c) protease resistance of a defined MtlA fragment observed exclusively in the presence of membranes. Post-translational addition of membrane vesicles allowed membrane association of MtlA but did not allow efficient integration. In cell-free systems having reduced levels of the export factors SecA and SecB and exhibiting defective translocation of preOmpA and preLamB, insertion of the in vitro synthesized MtlA apparently occurred normally. In contrast, when membranes from the secY24ts mutant or trypsin-treated membranes were used, insertion of MtlA was reduced. In vivo experiments monitoring the permease activity of MtlA in the secA and secY mutants supported the conclusions of the in vitro results. Thus, the insertion of MtlA is essentially SecA- and SecB-independent but may be dependent on SecY and/or an as yet unidentified membrane protein. The requirements for the insertion of the mannitol permease are therefore clearly different from those for the translocation of most proteins having a cleavable hydrophobic signal sequence.

Adenosine Triphosphatases↗
PubMedDate not supplied

Effect of surface chemistry on the rate of osseointegration of sintered porous-surfaced Ti-6Al-4V implants.

PURPOSE: The effect of adding a thin sol-gel-formed calcium phosphate (CaP) coating to sintered porous-surfaced titanium alloy (Ti-6Al-4V) implants on rates of initial bone ingrowth was investigated. MATERIALS AND METHODS: Control implants (as manufactured) and similar implants with sol-gel CaP coatings were randomly placed in distal femoral rabbit condyles (1 implant/leg). After healing for 6, 9, 12, and 16 days, 8 of 10 rabbits in each time group were assessed for maximum implant pullout force (N) and interface stiffness (N/mm). Selected extracted implants also were examined by secondary electron imaging to characterize affected surfaces. The implants of the remaining 2 rabbits in each group were examined by backscattered scanning electron microscopy (BSEM). RESULTS: Significantly greater pullout forces and interface stiffness were found for CaP-coated implants at 6 and 9 days. At 6 days, BSEM revealed bone ingrowth on CaP-coated implants but not on control implants. Secondary electron imaging and BSEM observations also suggested greater bone ingrowth with CaP-coated porous implants at 9, 12, and 16 days. DISCUSSION: Sol-gel-formed CaP surface films significantly enhance rates of bone ingrowth into sintered porous-surfaced implants. CONCLUSION: This surface treatment may have a number of clinical benefits, including shortening the period prior to functional loading of such implants and improving treatment outcomes in situations of poor bone quality and/or quantity. (More than 50 references).

Alloys↗
PubMedDate not supplied

Critical evaluation of the standard hydrolytic resistance test for glasses used for containers for blood and parenteral formulations.

As prescribed by pharmacopoeias, containers should meet certain condition of stability to be used for pharmaceutical products. Glass containers are classified according to their resistance to chemical attack, a test executed by heating the glass in contact with water for 30 min at 121 degrees C. The USP powdered glass test for glass containers was applied to different kinds of glasses used as containers for parenteral formulations. In this experiment not only the released alkalinity was measured but also the release of glass constituents: silicate, borate, sodium, and aluminum, and also the release of some impurities as copper and lead. The USP powdered glass test was also carried out with glass ampoules, clear and amber, in the presence of solution of some inorganic salts, NaCl, KCl, CaCl2, MgCl2, NaHCO3, NaH2PO4, KH2PO4, and sodium gluconate, citric acid and glucose. The results showed that even when releasing very low alkalinity, glasses also released their constituents, in concentration ranges from 8.8 to 33 mg/l for silicate, 0.9 to 6.9 mg/l for borate, 3 to 37 for mg/l for sodium and 0.5 to 2.4 mg/l for aluminum. More expressive results were found, however, for the tests done with solutions instead of pure water. The tests showed that, for most of the solutions, while the measured alkalinity was very low, high levels of the other constituents were found. Basic solutions of bicarbonate and gluconate presented the higher levels of all investigated constituents, confirming the ability of basic solutions to attack and dissolve the glass network. Glucose and citric acid interacted with the glass surface, selectively extracting aluminum, copper, and lead. Whereas silicate, borate and sodium found in these solutions were at levels similar to those found with pure water, the aluminum level was almost 20 times higher. This specific action of citrate and glucose could be related to their metal-complexing ability. The results indicate that even so-called "chemical-resistant glasses," as measured by the hydrolytic resistance test, react with many substances when packaged in contact with them. The hydrolytic resistance test, when used as the sole measure of potential drug-container compatibility, is not reliable.

Blood Preservation↗
PubMed1992

Evaluation of a photodiode array/HPLC-based system for the detection and quantitation of basic drugs in postmortem blood.

A systematic analytical approach has been developed for liquid chromatography determination of a number of basic drugs in postmortem blood. Using selective extraction, that is, back extraction into 0.2N sulfuric acid and 6N hydrochloric acid after the initial extraction with toluene under basic conditions (from 2 mL of blood), basic and weakly basic drugs, such as propranolol and diazepam, can be simultaneously quantitated and identified with a high degree of confidence. A microcomputer-based photodiode array detector was used to evaluate peak purity and facilitate peak identification. An automatic library search was performed at the end of each analysis using the system software. The method was validated for within-day and between-day precision for ten basic drugs at two concentrations. The coefficient of variation for the between-day precision was less than 8.7%. Accuracy of the assay was tested at four concentrations using linear regression analysis. The coefficients of determination (r2) for all ten drugs were greater than 0.99, and their slopes were close to unity. The chromatographic conditions developed are suitable for the screening of several basic, acidic, amphoteric, and neutral drugs. Retention data and ultraviolet spectral data for 119 drugs on two reversed-phase columns, using acidic mobile phases, are also presented.

Blood Chemical Analysis↗
PubMed1992

Electron microscopy of native cartilage oligomeric matrix protein purified from the Swarm rat chondrosarcoma reveals a five-armed structure.

Cartilage oligomeric matrix protein was isolated in the native state from the Swarm rat chondrosarcoma. A crucial step was its selective extraction with EDTA-containing buffer. The purified protein was subjected to electron microscopy using rotary shadowing and negative stain. The images allowed the construction of a structural model. The bouquet-like protein consists of five 28-nm-long arms containing a peripheral globular domain, a flexible strand, and a central assembly domain, where the five arms meet in a cylindrical structure.

Animals↗
PubMed1992

Microtubules and microtubule-associated proteins in resting and mitogenically activated normal human peripheral blood T cells.

The binding of an appropriate ligand to its specific receptor on the membrane of T cells triggers a cascade of events involved in T cell activation. An important yet unanswered question is how the mitogenic signals are transmitted through the cytoplasm and into the nucleus. The present study was carried out to determine changes in the microtubule (MT) system, following T cell activation. Fluorescence microscopy was employed to examine the organization of the microtubule network in human peripheral blood T cells in response to four different mitogens (phytohemagglutinin, concanavalin A, anti-CD3, and phorbol 12-myristate 13-acetate). The microtubules increase in length, number, and complexity of distribution 20 h after mitogenic stimulation. Using an in situ direct analysis protocol consisting of selective extraction of cells with detergent and Ca2+, 11 protein species, which fulfill the operational definition of microtubule-associated proteins (MAPs), were identified in resting human T cells. Alterations in the expression of these protein species were studied following mitogenic stimulation. These alterations in MAPs expression were also found in purified blast cell fractions indicating that they were specific changes occurring in activated T cell populations. These observations suggest a role for MT and MAPs in the cascade of human T cell activation.

Cell Cycle↗
PubMed1992

[Purification, amino acid composition and N-terminal sequence of the major protein (protein H) of the outer membrane of Pasteurella multocida].

The major protein (protein H) of the outer membrane of Pasteurella multocida was purified by size-exclusion chromatography after selective extraction with detergents. The protein forms homotrimers which are stable in the presence of SDS at room temperature. Upon treatment at 100 degrees C, the protein is fully dissociated by the detergent into monomers exhibiting an apparent molecular mass of 37 kDa as estimated by electrophoresis. The amino acid composition of protein H is characterized by a low hydropathy index (HI = -0.40) and is strongly related to the compositions of bacterial porins, notably porins P2 (Haemophilus influenzae), PIA (Neisseria gonorrhoeae) and Cl.2 ("class 2 porin" of N. meningitidis). The N-terminal amino acid sequence of protein H shares a strong homology with those of porins OmpC (Escherichia coli) and P2. These data indicate that protein H of P. multocida is a porin belonging to the superfamily of the non-specific porins of Gram-negative eubacteria outer membrane.

Amino Acid Sequence↗
PubMed1991

Improved light microscopic demonstration of D-amino acid oxidase activity in cryotome sections using cerium ions as capturing and amplifying agent--the Ce/Ce-H2O2-DAB procedure.

The light microscopical demonstration of D-amino acid oxidase (AAOX) activity with cerium (Ce III) as the capturing agent was improved. The incubation medium was stabilized by the employment of triethanolamine and detrane complexed cerium. A considerable increase in intensity of the reaction was accomplished by treatment of the AAOX-incubated sections with Ce III which reacted with the primary reaction product Ce IV-perhydroxide to form Ce IV-hydroxide. In this way the primary reaction product was reduced and enlarged concomitantly. The Ce IV-hydroxide was converted into Ce IV-perhydroxide by H2O2, which was visualized by blue-black stained Ni-DAB complexes. Thus, Ce III is used as capturing agent as well as amplifier (Ce/Ce-H2O2-DAB method). The primary reaction product Ce III-phosphate formed by coreacting phosphatases was selectively extracted by citrate containing glycine-NaOH buffer while Ce IV-perhydroxide remained in the sections. In model experiments it was proven that the perhydroxide groups in the Ce IV-perhydroxide compound initiate predominantly the DAB polymerization while the contribution of Ce III and Ce IV is small.

3,3'-Diaminobenzidine↗
PubMed2006

[Changes of nuclear matrix proteins during differentiation of human osteosarcoma MG-63 cells induced by HMBA].

Human osteosarcoma MG-63 cells were induced into differentiation by hexamethylene bisacetamide (HMBA). Its nuclear matrix proteins were selectively extracted, and subjected to two dimensional gel electrophoresis analysis. The resulted protein patterns were analyzed by Melanie software. There were 12 spots changed remarkably during the differentiation induced by HMBA, nine of which were identified. The up-regulated proteins were identified as MHC class II antigen, interferon-stimulated gene factor 3d, hypothetical protein DKFZp434M2221.1,8-hydroxy-guanine glycosylase homolog ogg1, and vimentin. The down-regulated ones were hnRNP A2/B1 and actin; and two newly expressed proteins under induction were 60S ribosomal protein L21 and ST2 protein. This study suggests that the induced differentiation of carcinoma cells is accompanied with changes of nuclear matrix proteins, and confirms the presence of some specific nuclear matrix proteins associated with carcinoma cell growth and differentiation. The changed nuclear matrix proteins are potential markers for cancer diagnosis or targets for cancer therapy.

Acetamides↗
PubMed1991

[Immunosorption of individual HIV proteins and virions].

Immunosorbents specifically binding native (gp160, gp120, gp41) and recombinant env proteins and HIV-I virions were synthesized on the basis of Sepharose 4B and Silica with immobilized ligands such as gamma-fraction of rabbit antiserum to HIV-I proteins and purified antibodies to env proteins of HIV-I. The possibility was shown of selective extraction of HIV-I virions and individual HIV proteins both in vitro and in vivo. The titer of virus antigens (in ELISA) after perfusion via an immunosorbent of patterns with a high content of virions and HIV-I proteins was 8 times as low as the starting titer (after perfusion via the control sorbent it was 2-fold decreased). Extracorporeal immunosorption in animals after intravenous injection of recombinant env protein permitted the latter's titer to be 5 times lower. After perfusion via the control sorbent the titer dropped by at least 20% as compared with the starting titer. The possibility of using immunosorption in multimodality therapy of AIDS is under discussion.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

[Radiation-induced disorders of steroid-metabolizing function of the liver].

A study was made of metabolic derangement of exogenous cortisol in isolated perfused liver of irradiated rats. The animals were exposed to x-radiation at doses of 2, 4, 8, 10 and 12 Gy. A 72 h irradiation was followed by decapitation and perfusion of the liver with cortisol. Cortisol and its metabolites in a perfusion medium were determined by thin-layer chromatography. Irradiation at the doses of 2 and 4 Gy resulted in no noticeable changes of steroid-metabolizing liver function. At the lethal doses of 8, 10 and 12 Gy cortisol absorption by the liver was gradually decreased and accompanied by accumulation in the perfusion medium of excessive amounts (as compared to control) of tetrahydrocortisone, cortisone, and unidentified metabolites that may be associated with disorder of their conversion at subsequent stages of metabolism. A method of selective extraction of varied polarity fractions of hydrocortisone metabolites from a perfusate has also shown that irradiation inhibits transformation of steroids into more polar compounds.

Animals↗
PubMed1991

[Factual databanks of the International Register of Potentially Toxic Chemicals].

The computerized IRPTC data bank will cover the needs for factual information of the Toxicological Information System established in the Institute of Occupational Medicine. The conception and principles of the International Register of Potentially Toxic Chemicals (IRPTC) have been discussed. The main aim of the data bank is providing its users with information necessary to assess the potential threat posed by chemicals to man and his environment. The structure of the data bank, the rules for selection, extraction and presentation of data have been discussed as well as data sources, data management and dissemination of information.

Databases, Factual↗
PubMed1991

Immunoaffinity partitioning: synthesis and use of polyethylene glycol-oxirane for coupling to bovine serum albumin and monoclonal antibodies.

Polyethylene glycol (PEG)-oxirane was synthesized by reacting aminated monomethoxy-PEG 5000 (NH2-MPEG 5000) with butanediol diglycidyl ether and used to derivatize bovine serum albumin (BSA) and monoclonal antibodies (mAb) against horseradish peroxidase (HRP) and porcine lactate dehydrogenase isoenzyme 5, respectively. Determination of oxirane end groups revealed a very high number, which arise from the chain breaks of the polymer. Covalent coupling of PEG-oxirane to BSA resulted in 30-50 times higher partition coefficients under optimized conditions. The mAb investigated could be modified with PEG-oxirane while retaining its binding properties and could be used as an affinity ligand for selective extraction of Ag in immunoaffinity partitioning. However, a high degree of modification results in a lower binding constant of mAb anti-HRP and higher [mAb]/[Ag] concentration ratios in immunoaffinity partition experiments.

Antibodies, Monoclonal↗
PubMed1991

[Determination of 3,3'-dichlorodibenzoyl peroxide impurity in 3-chloroperbenzoic acid].

An ultraviolet spectrophotometric method has been developed for the determination of 3,3'-dichloro dibenzoyl peroxide impurity in 3-chloroperbenzoic acid, an important epoxidation agent in drug (especially steroid) syntheses. The method is based on the selective extraction of the main component by aqueous alkali from a chloroformic solution. The solution of the test substance (0.05-0.1 g in 50 ml chloroform) is extracted four times with 20 ml portions of 0.1 M aqueous sodium hydroxide and the absorbance of the resulting chloroformic solution in measured at 286 nm to calculate the content of 3,3'-dichloro dibenzoyl peroxide impurity. Beer's law is obeyed in the 0-10% impurity range. The A10/01 cm.value is 77.9 and the correlation coefficient of the regression equation was found to be 0.995. The relative standard deviation of the measurement in the case of 2% impurity was +/- 0.43%.

Benzoyl Peroxide↗
PubMed1991

Acute histopathological changes produced by Penicillium aurantiogriseum nephrotoxin in the rat.

Shredded wheat moulded by an isolate of Penicillium aurantiogriseum elicited progressive histopathological changes at the rat renal cortico-medullary junction during 5 days of dosing, when incorporated into diet as a 20% component. The changes of acute tubular necrosis and regeneration were seen in the P3 segment of the nephron. In rats exposed to contaminated diet for 5 days the histopathological changes regressed in severity by about one-half within a further 4 days on normal diet and by 7 days the tubular epithelium was nearly normal. A partially purified fraction of an alcohol extract, selected by preparative high-voltage electrophoresis and anion exchange and notably rich in amino-compounds, was typically nephrotoxic when given in diet over 4 days. Acute marked tubular necrosis also occurred when the same fraction was given intraperitoneally over a similar period. The acute histological changes provide a rapid bioassay for this Penicillium nephrotoxicity and facilitate the search for the toxic metabolite(s). The cumulative expression of necrosis and repair over only a few days in tubular epithelium suggests that chronic exposure will elicit a more complex pathology which might serve as an experimental model for the idiopathic Balkan endemic nephropathy.

Animals↗