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PubMed2005

Survey of albumin purification methods for the analysis of albumin-organic toxicant adducts by liquid chromatography-electrospray ionization-tandem mass spectrometry.

HSA has been shown to react with many organic toxicants to form adducts that are useful biomarkers for exposure. Albumin isolation is an important first step for the analysis of these protein-toxicant adducts. We tested several approaches to isolate albumin from serum treated with an electrophilic organic toxicant known to form adducts with albumin, i.e., sulfur mustard agent (HD) (2,2'-dichloroethyl sulfide), in order to evaluate these techniques as purification methods. To select the most efficient isolation strategy, methods were evaluated using gel electrophoresis, total protein quantitation, and peptide-adduct identification by MS. Results suggest that the albumin-rich fractions obtained can be used to identify exposure by quantitating the albumin adducts to electrophilic organic toxicants such as HD. The HiTrap Blue HP albumin isolation system appears to display the most promising results for purifying albumin to detect HD-adducts, exhibiting high purification efficiency, satisfactory albumin recovery, promising specificity, and a higher loading capacity for serum.

Chromatography, Liquid↗
PubMed2004

Folic acid and vitamin E supplementation effects on homocysteinemia, endothelial function and plasma antioxidant capacity in young myocardial-infarction patients.

We examined the effects of folate (either alone or co-supplemented with Vitamin E) on endothelial function in hyperhomocysteinimic patients and correlated results with serum antioxidant capacity. A randomized trial was carried out in 30 young patients with recent acute myocardial infarction (AMI) and high plasma homocysteine concentrations. Intervention consisted of high doses of folate, either alone (group A) or in combination with Vitamin E (group B), for three months. Main outcome measures were endothelial function, serum antioxidant capacity, and homocysteinemia. Folic acid treatment reduced plasma homocysteine concentrations in both groups by 41% and, as compared with baseline values, was associated with a significant (P<0.001) improvement of endothelial function (from 0.322 (0.03) to 0.450 (0.02)mm in group A and from 0.338 (0.03) to 0.584 (0.04)mm in group B). However, there was no difference in endothelial function improvement between folic acid and folic acid plus Vitamin E group. Plasma antioxidant capacity significantly (P<0.001) increased in both groups. In conclusion, beneficial effects of folic acid on vasomotion appear to be independent of antioxidant action but, rather, seem to be strongly associated with reduction of homocysteinemia. Confirming previous reports, the effects of Vitamin E are still equivocal.

Adult↗
PubMed2000

Very rare complementation between mitochondria carrying different mitochondrial DNA mutations points to intrinsic genetic autonomy of the organelles in cultured human cells.

In the present work, a large scale investigation was done regarding the capacity of cultured human cell lines (carrying in homoplasmic form either the mitochondrial tRNA(Lys) A8344G mutation associated with the myoclonic epilepsy and ragged red fiber (MERRF) encephalomyopathy or a frameshift mutation, isolated in vitro, in the gene for the ND4 subunit of NADH dehydrogenase) to undergo transcomplementation of their recessive mitochondrial DNA (mtDNA) mutations after cell fusion. The presence of appropriate nuclear drug resistance markers in the two cell lines allowed measurements of the frequency of cell fusion in glucose-containing medium, non-selective for respiratory capacity, whereas the frequency of transcomplementation of the two mtDNA mutations was determined by growing the same cell fusion mixture in galactose-containing medium, selective for respiratory competence. Transcomplementation of the two mutations was revealed by the re-establishment of normal mitochondrial protein synthesis and respiratory activity and by the relative rates synthesis of two isoforms of the ND3 subunit of NADH dehydrogenase. The results of several experiments showed a cell fusion frequency between 1.4 and 3.4% and an absolute transcomplementation frequency that varied between 1.2 x 10(-5) and 5.5 x 10(-4). Thus, only 0.3-1.6% of the fusion products exhibited transcomplementation of the two mutations. These rare transcomplementing clones were very sluggish in developing, grew very slowly thereafter, and showed a substantial rate of cell death (22-28%). The present results strongly support the conclusion that the capacity of mitochondria to fuse and mix their contents is not a general intrinsic property of these organelles in mammalian cells, although it may become activated in some developmental or physiological situations.

Aging↗
PubMed1978

Effect of ritodrine on the bladder capacity in unanaesthetized pigs.

A cystometric investigation was carried out in unanaesthetized pigs. During intravenous infusion of ritodrine (10, 30 and 50 microgram/kg/min.) a dose-dependent and significant increase of the bladder capacity was obtained. A concomitant significant elevation of the heart rate followed the administration of the drug.

Animals↗
PubMed1991

Repair capacity and kinetics in spheroids from a lung metastasis of a human soft tissue sarcoma: a growth delay study.

Spheroids grown from the human cell line EF8 of a lung metastasis of a human malignant fibrous histiocytoma were given fractionated irradiation with 60Co gamma rays at passages 31 and 32. The mean diameter of the spheroids at the time of treatment was 250 microns. Growth delay was used as the end point in these studies. Two experiments were carried out to determine the capacity and kinetics of repair of sublethal damage. In the first experiment, one, two, and five fractions were given at three or four dose levels with fixed intervals of 360 min. In the second experiment, schedules with two and four dose fractions and intervals of 0, 20, 60, 120, and 360 min were used, each at two dose levels. Data analysis was performed by a direct method based on the alpha/beta model and first-order repair kinetics of radiation damage. In both experiments, the alpha/beta value of EF8 spheroids was estimated to be about 8 (6-10) Gy. The rate constant of repair, mu, and its 95% confidence interval were estimated to be 0.62 (0.40-0.84) 10(-2) min-1, equivalent to a half-time of repair (T1/2) of 112 (83-172) min. A more detailed analysis of the data of the second experiment revealed a significant dependence of the rate constant of repair, mu, on the total radiation effect induced by the fractionated radiation treatments with short overall times. With increasing level of effect, mu decreased. These data indicate that the half-time of recovery of a human tumor can be longer than that of the surrounding normal tissue, in this case lung, at least for a limited range of doses and for some fractionation schedules.

Cobalt Radioisotopes↗
PubMed1996

Permissible errors in managing property: an approach to the threshold of capacity.

OBJECTIVE: To demonstrate a practical approach to describing the threshold of mental capacity. METHOD: A retrospective analysis of 62 cases of assessments for capacity to manage property was carried out to record the type and frequency of errors. RESULTS: For items on the Mini-Mental State Examination (MMSE), there was no clear demarcation of items associated with a judgement of capable. On the clinical criteria, several items almost completely distinguished capable from incapable subjects. CONCLUSIONS: The permissible error approach makes the threshold of capacity explicit. It is well suited to the emphasis put on functional performance in the evaluation of mental capacity.

Canada↗
PubMed2005

Study of the removal of mercury(II) and chromium(VI) from aqueous solutions by Moroccan stevensite.

The objective of the present study was to investigate the adsorption of the heavy metals mercury(II) and chromium(VI), from aqueous solutions, onto Moroccan stevensite. A mineralogical and physicochemical characterization of natural stevensite was carried out. In order to improve the adsorption capacity of stevensite for Cr(VI), a preparation of stevensite was carried out. It consists in saturating the stevensite by ferrous iron Fe(II) and reducing the total Fe by Na(2)S(2)O(4). Then, the adsorption experiments were studied in batch reactors at 25+/-3 degrees C. The influence of the pH solution on the Cr(VI) and Hg(II) adsorption was studied in the pH range of 1.5-7.0. The optimum pH for the Cr(VI) adsorption is in the pH range of 2.0-5.0 while that of Hg(II) is at the pH values above 4.0. The adsorption kinetics were tested by a pseudo-second-order model. The adsorption rate of Hg(II) is 54.35 mmol kg(-1)min(-1) and that of Cr(VI) is 7.21 mmol kg(-1)min(-1). The adsorption equilibrium time for Hg(II) and Cr(VI) was reached within 2 and 12 h, respectively. The adsorption isotherms were described by the Dubinin-Radushkevich model. The maximal adsorption capacity for Cr(VI) increases from 13.7 (raw stevensite) to 48.86 mmol kg(-1) (modified stevensite) while that of Hg(II) decreases from 205.8 to 166.9 mmol kg(-1). The mechanism of Hg(II) and Cr(VI) adsorption was discussed.

Adsorption↗
PubMed1988

Tracing tissues with 4-ipomeanol-metabolizing capacity in rats.

Rats were given 3H-labelled 4-ipomeanol intravenously and whole-body autoradiography with freeze-dried sections, or with sections extracted with trichloroacetic acid, water and organic solvents, was performed to examine the disposition of unbound and bound radioactivity in various tissues. Microautoradiography with glutaraldehyde-fixed, resin-embedded material was used to investigate the cellular distribution of bound metabolites. Based on the data obtained from these experiments in vitro incubations with tissue-slices were carried out to examine the capacity by various tissues to form tissue-bound 3H from the 3H-labelled 4-ipomeanol and autoradiography of isolated organs after incubation with 3H-labelled 4-ipomeanol was performed to study the localization of radioactivity under in vitro conditions. The results showed a high formation of tissue-bound 3H in the lung in vitro and a localization of bound metabolites in several structures of the lung in vivo. In vitro formation of tissue-bound 3H was also found in the nasal olfactory and respiratory mucosa, the hard palate, the trachea, the liver and the kidney and this was also correlated with a localization of bound 3H in these tissues in vivo. Incubations of the lung, the nasal olfactory mucosa, the hard palate and the liver in CO- or N2-atmospheres or in the presence of the cytochrome P-450-inhibitor metyrapone showed decreased formation of tissue-bound 3H from the 3H-labelled 4-ipomeanol, indicating a role of cytochrome P-450 in the metabolism of 4-ipomeanol in the various tissues. The correlation between the in vitro capacity of various tissues to metabolize the 4-ipomeanol and the in vivo accumulation of tissue-bound metabolites in the same tissues indicate that a local bioactivation of the 4-ipomeanol takes place in these tissues in vivo.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1986

The NADPH:O2 oxidoreductase of human neutrophils. Stoichiometry of univalent and divalent reduction of O2.

The ratio of superoxide production to oxidation of NADPH affected by the NADPH:O2 oxidoreductase of human neutrophils is strongly influenced by pH, NADPH substrate concentration, aging of the enzyme, or its exposure to excess deoxycholate. Freshly prepared enzyme exhibited a Km for NADPH of 52 microM as determined by assaying NADPH oxidase activity, or approximately 33 microM by measurement of superoxide formation. In the range of 100-150 microM NADPH at pH 7.6 and in the presence of 0.06% deoxycholate, the univalent flux of electron equivalents given up by NADPH to O2 was 99%. Following storage of the oxidoreductase overnight on ice, its Km for NADPH rose to 125 microM as determined by monitoring oxidation of NADPH but was unaltered when measured in terms of superoxide production. Concomitantly, its capacity to affect univalent reduction of O2 fell approximately 20-30% under the same assay conditions. Univalent flux rates of less than 40% were observed with exposure of the enzyme to concentrations of deoxycholate in excess of 0.1% or to pH values below 6.0 or above 8.0. The capacity of the enzyme to carry out univalent reduction fell with increasing NADPH concentrations in a manner resembling that previously reported with increasing concentrations of xanthine in the case of xanthine oxidase (Fridovich, I. (1970) J. Biol. Chem. 245, 4053-4057). The reduced form of the neutrophil oxidoreductase, like xanthine oxidase, thus appears to be capable of conducting both 1- and 2-electron transfer steps in reducing O2. Its capacity to affect univalent reduction of O2 depends upon the concentration of electron donor (NADPH) supplied as well as conditions of storage and assay of the native enzyme.

Deoxycholic Acid↗
PubMed1984

Visual cycle in the mammalian eye. Retinoid-binding proteins and the distribution of 11-cis retinoids.

This work was designed to provide an insight into the mammalian visual cycle by investigating the possible function of retinoid-binding proteins in this system, and the distribution and type of 11-cis retinoids present in the interphotoreceptor matrix and the cytosols of the retinal pigment epithelium and retina. The total retinol and retinal in the soluble fractions from these three compartments was 8% (3.31 nmol/eye) of the retinyl palmitate and stearate stored in the pigment epithelium membrane fractions (39 nmol/eye). Only small amounts of retinoids were detected in the rod outer segment cytosol. The insoluble fractions also contained retinol, nearly all of which was found in the retina. The retinoids in the soluble fractions appeared to be bound to cellular retinol-binding protein (CRBP), cellular retinal-binding protein (CRA1BP) and interstitial retinol-binding protein (IRBP, a high-Mr glycoprotein). Using immunospecific precipitation, immunoblot and immunocytochemical techniques it was demonstrated that IRBP was localized in the interphotoreceptor matrix and was synthesized and secreted by the retina, a process that did not require the protein to be glycosylated. The amount of retinol bound to IRBP increased if the eyes were exposed to light, when it was estimated that the protein carried up to 30% of its full capacity for all-trans retinol. In addition to all-trans retinol, IRBP carried smaller amounts of 11-cis retinol. The proportion of 11-cis retinol was frequently higher in eyes that had been protected from illumination, suggesting that IRBP plays a role in rhodopsin regeneration during dark-adaptation. Additionally, endogenous 11-cis retinoids in the retina and RPE cytosols were bound to an Mr 33,000 protein tentatively identified as CRA1BP. The 11-cis retinoid in the retina cytosol was mainly in the form of retinol, while in the RPE cytosol it was mainly in the form of retinal. Substantial amounts of 11-cis retinol were also found in the insoluble (membrane) fraction from the retina. It is suggested that in the mammalian retina 11-cis retinol is generated from all-trans retinol (possibly in the Muller cells). Lack of an 11-cis retinol oxidoreductase in the retina prevents it from being utilized for rhodopsin regeneration until it has been transported to the pigment epithelium, where it is converted to 11-cis retinal and returned to the rod outer segments. It is also suggested that IRBP may be implicated in the transport of retinoids between the rod outer segments, the Muller cells and the pigment epithelium.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2006

[Streptococcus agalactiae in nonpregnant adults].

UNLABELLED: The pathogenic capacity of streptococcus agalactiae or Group B Streptococcus (GBS) has been increasing in nonpregnant adults. We carried out a study about the pathogenic capacity and susceptibility to antibiotics of GBS strains isolated between January 2003 and June 2004 in Farhat Hached hospital of Sousse (Tunisian general hospital). METHODS: Identification of strains was carried out according to usual bacteriological characters. Susceptibility of GBS to antibiotics was carried out according to CA-SFM recommendations. RESULTS: during the study period, sixty strains were isolated. They were essentially isolated from the urinary tract (52%) and the skin (36.2%). Women accounted for 68 percent of the cases. Among the 30 hospitalized patients, 20 (66%) had serious underlying disease. Diabetes mellitus was predominant (80%). All group B streptococci isolates were susceptible to amoxicillin, penicillin G, vancomycin and to pristinamycin. Sixty four percent of isolates were susceptible to erythromycin. Among the invasive infection, caused by GBS in nonpregnant adults, skin and urinary tract infections were the most common. All isolates were susceptible to amoxicillin, penicillin G. vancomycin and to pristinamycin.

Anti-Bacterial Agents↗
PubMedDate not supplied

Local health departments in Washington State use APEX to assess capacity.

THE ASSESSMENT PROTOCOL for EXCELLENCE in PUBLIC HEALTH process was carried out in the state of Washington to assess local health department capacity and to identify their self-perceived strengths and weaknesses. Staff from 24 of the 32 local health departments in Washington completed organizational capacity assessments. Fifty percent or more of the health departments identified the following eight indicators as strengths: legal authority, public policy and implementation, budget development, financial reporting and administration, audit, financial documentation, organization and structure of program management, and policy board procedures. Seven indicators were identified as weaknesses by 50% or more of the respondents: legal counsel, mission and role, data collection and analysis, planning and development, evaluation and assurance of community health assessment, community health assessment and planning, and community health policy. The results of the assessment highlight the traditional organizational and service delivery strengths of the local health departments and point out weaknesses in their ability to assess community health and to develop communitywide health policy.

Community Health Services↗
PubMed1999

The implant neck: smooth or provided with retention elements. A biomechanical approach.

A combined three-dimensional and axisymmetric finite element analysis was made of the effect upon the peak interfacial shear stress of providing an axially loaded mandibular dental implant with retention elements all the way up to the crest of the implant as opposed to a smooth neck. The effect of increased wall thickness of the implant and of using bi-cortical fixation as opposed to uni-cortical fixation was also studied. Retention elements at the implant neck were found to bring about a major decrease in the peak interfacial shear stress. Increased wall thickness and bi-cortical fixation also resulted in decreased peak interfacial shear stress but this effect was minor. The interpretation of this was that all these three measures increase the capacity of the implant to carry axial loads. Thus from a biomechanical viewpoint it appears to be advantageous to provide the neck of screw-shaped implants with retention elements, for example a rough surface of suitable micro-architecture and/or a micro-thread. It is furthermore suggested that retention elements at the implant neck will counteract marginal bone resorption in accordance with Wolff's law. This paper is a revision of: Hansson, S. (1997) Some steps to improve the capacity of dental implants to resist axial loads. In: Hansson, S., ed. Towards an optimized dental implant and implant bridge design: A biomechanical approach. Thesis. Göteborg: Chalmers University of Technology.

Alveolar Process↗
PubMed2006

Assessing community needs and agency capacity--an integral part of implementing effective evidence-based interventions.

Community-based organizations and public health departments have historically applied for and received funding to implement a variety of HIV prevention interventions, but it is unclear how they make decisions regarding which interventions to implement or whether their agency has sufficient capacity and/or resources to effectively carry them out. Assessment activities can play a valuable role in helping agencies make these decisions by providing information to better target services. Recent funding efforts supporting the Diffusion of Effective Behavioral Interventions Project and other evidence-based approaches for HIV prevention require that agencies possess basic skills to effectively conduct individual-, group-, or community-level interventions, as well as the specific activities associated with an evidence-based intervention (EBI). We examine the link among community assessment, agency capacity, and intervention effectiveness, and provide resources to better guide programs in assessing their communities and organizations in order to implement the most effective EBI.

Efficiency, Organizational↗
PubMed2006

Continuous fixed bed biosorption of reactive dyes by dried Rhizopus arrhizus: determination of column capacity.

A continuous fixed bed study was carried out by using dried Rhizopus arrhizus as a biosorbent for the removal of three reactive dyes; Gemacion (Procion) Red H-E7B (GR), a monoclorotriazine mono-azo type reactive dye; Gemazol Turquise Blue-G (GTB), a vinyl sulfone mono-azo type reactive dye and Gemactive (Reactive) Black HFGR (GB), a vinyl sulfone di-azo type reactive dye from aqueous solution. The effect of operating parameters such as flow rate and inlet dye concentration on the sorption characteristics of R. arrhizus was investigated at pH 2.0 and at 25 degrees C for each dye. Data confirmed that the total amount of sorbed dye decreased with increasing flow rate and increased with increasing inlet dye concentration for each dye. The column biosorption capacity of dried R. arrhizus was 1007.8 mg g(-1) for GR dye, 823.8 mg g(-1) for GTB dye and 635.7 mg g(-1) for GB dye at the highest inlet dye concentration of approximately 750 mg l(-1) and at the minimum flow rate of 0.8 ml min(-1). Thomas and Yoon-Nelson models were applied to experimental data to predict the breakthrough curves and to determine the biosorption capacity of the column for each dye useful for process design. Both models were found suitable for describing the whole dynamic behavior of the column with respect to flow rate and inlet dye concentration.

Adsorption↗
PubMed1995

Ultrarapid hydroxylation of debrisoquine in a Swedish population. Analysis of the molecular genetic basis.

Hydroxylation of debrisoquine, catalyzed by the cytochrome P450 CYP2D6 exhibits genetic polymorphism, with large inter-individual differences in metabolic capacity. About 7% of Caucasians carry deficient CYP2D6 alleles and lack the CYP2D6 enzyme (poor metabolizers). We have shown in two Swedish families, individuals carrying duplicated or amplified functional CYP2D6L-genes (CYP2D6L2), causing the opposite phenomenon, ultrarapid metabolism of debrisoquine. In the present study, the occurrence of extra copies of CYP2D6L-alleles was studied in relation to debrisoquine metabolic ratio (MR) in 270 Swedish Caucasians including 64 selected subjects with very rapid metabolism (MR < or = 0.2). Thirteen of the 64 subjects carried a duplicated CYP2D6-gene as identified by EcoRI and XbaI restriction fragment length polymorphism and allele-specific polymerase chain reaction-amplification of genomic DNA. A new allele with three active CYP2D6L-genes was identified, characterized by an XbaI 54 kilobase fragment. This indicates a preference of the CYP2D6L-gene to be amplified compared to other CYP2D6 genes. Only one subject with an MR higher than 0.2 carried the duplicated CYP2D6L-allele, also being heterozygous for the defect CYP2D6B-allele. The overall frequency of the duplicated/amplified CYP2D6-allele was about 1%, and was present in 40% of subjects with MRs < or = 0.1. Thus, other variant CYP2D6-genes may exist that cause increased CYP2D6 activity. In conclusion, a haplotype with duplicated or amplified functional CYP2D6 genes predicts, with high accuracy, ultrarapid metabolism of debrisoquine. Genotyping for this CYP2D locus variant might be of value in patients not responding to generally recommended doses of CYP2D6 substrates, to distinguish between high metabolic capacity and noncompliance.

Cytochrome P-450 CYP2D6↗
PubMedDate not supplied

The protective effect of Ketotifen in respiratory allergy.

During the last two years many works have dealt with the anti-anaphylactic properties of HC 20-511, which chemically belongs to the cycloheptathiophene group of drugs. The excellent results obtained by different authors using this drug in various allergies, decided us to study its protective use in patients affected by rhinitis and/or extrinsec bronchial asthma, especially in connection with pollinoisis. We selected a group of patients of both sexes over 12 years of age, including those who had already received immunotherapy treatment. Diagnosis was determined by means of a clear clinical history, skin tests, and exposure tests to specific antigens, using the Gronemeyer and Fuchs method. The drug was administered orally (1 mg./twice a day) for 3 months. Exposition tests were carried out before beginning treatment and at 30 and 90 days, and measurement of vital capacity, FEV1, Maximal flow and Pneumometry were carried out. A check on the clinical state of the patient, as well as on his tolerance to the drug, and on additional intake of other anti-asthmatic drugs (corticoids, Beta-stimulants) was made every 15 days. The results were highly satisfactory and a positive improvement in the clinical state of 70% of the patients after three months of treatment was noticed. When carrying out bronchial provocation tests, a minor decrease in FEV1 as well as in bronchopneumetric values were undoubtedly noticed in the patients under treatment when compared with the basal tests. Tolerance to the drug was excellent, its undesirable effects being secondary to its antihistaminic activity.

Administration, Oral↗
PubMed1983

[Interaction of Shigella sonnei phase-I strains carrying F'- or R386 plasmids with continuous HeLa- and L-line cells].

The region of S. sonnei chromosome, located to the left of the gene lac I, has been found to be linked with the capacity of these bacteria for penetrating epithelial cells: this capacity is sharply suppressed in transconjugates carrying plasmids F' which cover the above-mentioned chromosomal region in recipients. The loss of virulence by transconjugates with transferred plasmids F'lac is not linked with the transfer of F factor proper, as those transconjugates which have acquired plasmids F' from E. coli donor strains K = 12 X 363 or F'his 131, not covering the lactose region to the left of the gene lac I, retain their virulence. The transfer of plasmid R 386 having no analogs of bacterial chromosomal genes leads to the loss of virulence due to the oss of the invasive capacity of bacteria.

Animals↗

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