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1.
Int Endod J ; 54(5): 682-692, 2021 May.
Article in English | MEDLINE | ID: mdl-33300172

ABSTRACT

AIM: To characterize plasma cell subsets in chronic periapical lesions affecting permanent and primary teeth. METHODOLOGY: Only chronic periapical lesions without root canal treatment were selected. Twenty-one radicular cysts and 7 periapical granulomas affecting permanent teeth and 19 radicular cysts and 4 periapical granulomas affecting primary teeth were assessed for immunoglobulin (Ig) light chain (kappa and lambda), Ig heavy chain (IgG, IgG4, IgA, IgM and IgD) and plasma cell immunohistochemical markers (MUM1/IRF4, EMA and CD138). The data acquired were analysed by Student's t test, Mann-Whitney U, Friedman test followed by Dunn's multiple comparison test and Spearman's rank correlation. RESULTS: All cases were polyclonal (having similar kappa/lambda light chain ratios). IgG was most abundant compared to other Ig heavy chains (all, P < 0.001); like Ig light chains, but unlike IgA, there was greater expression of IgG in the primary compared to the permanent dentition, for both radicular cysts (P < 0.001) and periapical granulomas (P = 0.53). Notably, IgG4 expression was greater in the permanent than the primary dentition, for both radicular cyst (P < 0.05) and periapical granuloma (P = 0.65). IgM and IgD expression was scarce and variable, whereas plasma cell populations were detected efficiently through EMA, CD138 and MUM1/IRF4 markers, the latter being more sensitive in both dentitions. CONCLUSIONS: There were slight variations in the Ig light and heavy chain profiles in chronic periapical lesions when comparing the permanent and primary dentitions. The ability of IgG4+ plasma cell infiltration to modulate inflammatory responses in chronic periapical lesions arising from permanent as opposed to primary teeth should be considered in future studies.


Subject(s)
Periapical Granuloma , Radicular Cyst , Humans , Immunoglobulin G , Plasma Cells , Tooth, Deciduous
2.
Int Endod J ; 53(5): 627-635, 2020 May.
Article in English | MEDLINE | ID: mdl-31845371

ABSTRACT

AIM: To quantify M1 and M2 macrophages in radicular cysts of permanent (n = 14 cases) and primary teeth (n = 15 cases). METHODOLOGY: All patients who attended the School of Dentistry Ribeirão Preto, University of São Paulo with primary teeth or permanent molars that were scheduled for extraction and fulfilled the inclusion criteria: absence of pain; presence/absence of fistulae; extensive coronal destruction due to caries lesions without possibility of restoration; pulp necrosis; radiographically visible apical periodontitis; and no previous treatment, were selected. The radicular cysts were removed and subsequently submitted to histopathologic analysis in order to classify the type of inflammatory infiltrate. In addition, CD68 (M1+, M2+) and CD163 (M1-, M2+) markers were quantified through an immunohistochemistry analysis. The data acquired were submitted to a Mann-Whitney test, with a 5% significance level. RESULTS: The patients had a mean age of 38.6 years and 5.9 years for cysts associated with permanent and primary teeth, respectively. In the histopathological analysis, no significant difference (P = 0.87) was found between radicular cysts in primary and permanent teeth regarding the intensity of the chronic inflammatory infiltrate. A significantly greater prevalence of M2 macrophages (P < 0.05) was observed in the lesions of both permanent and primary teeth, even though both M1 and M2 macrophages were detected. No significant difference (P > 0.05) was found for M1 and M2 macrophages associated with the cysts of primary and permanent teeth. CONCLUSION: M1 and M2 macrophages were present in radicular cysts associated with primary and permanent teeth, with a greater quantity of M2 cells. The immunophenotypic quantification of M1 and M2 macrophage polarization in radicular cysts associated with primary and permanent teeth were similar.


Subject(s)
Periapical Periodontitis , Radicular Cyst , Adult , Dental Pulp Necrosis , Humans , Macrophages , Molar
3.
HIV Med ; 12(1): 31-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20497250

ABSTRACT

OBJECTIVE: The aim of the study was to compare the metabolic and morphological effects of enfuvirtide plus an optimized background (OB) regimen vs. OB alone (control group) in treatment-experienced patients in the T-20 vs. Optimized Regimen Only (TORO) studies. METHODS: Body composition and metabolic changes were investigated in patients over 48 weeks, based on fasting chemistries, body weight, and other anthropometric measurements. Dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT) scans were performed in a patient subgroup (n=155) at baseline and at weeks 24 and 48. RESULTS: At week 48, mean changes from baseline were similar between treatment groups for glucose, insulin, C-peptide, total cholesterol, low-density lipoprotein (LDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglyceride levels. The enfuvirtide group experienced a significant increase in body weight [mean change from baseline +0.99 kg; 95% confidence interval (CI) +0.54, +1.44] and, in those who had body scans, there was a significant increase in truncal fat (by DEXA: median change +419.4 g; 95% CI+71.3, +767.5) and total fat [visceral adipose tissue (VAT)+subcutaneous adipose tissue (SAT) by single-slice abdominal CT scan: median change +25.5 cm(2) ; 95% CI+8.9, +42.0] over 48 weeks; significant increases in these parameters were not seen in the control group. There was no significant change in truncal:peripheral fat ratio in either the enfuvirtide or the control group. CONCLUSION: The addition of enfuvirtide to an OB regimen does not appear to have unfavourable effects on fat distribution or metabolic parameters.


Subject(s)
Body Composition/drug effects , Dyslipidemias/chemically induced , HIV Envelope Protein gp41/adverse effects , HIV Fusion Inhibitors/adverse effects , HIV Infections/drug therapy , Peptide Fragments/adverse effects , Absorptiometry, Photon , Adolescent , Adult , Aged , Aged, 80 and over , Antiretroviral Therapy, Highly Active/adverse effects , Antiretroviral Therapy, Highly Active/methods , Body Weight/drug effects , Dyslipidemias/epidemiology , Enfuvirtide , Female , HIV Envelope Protein gp41/pharmacology , HIV Fusion Inhibitors/pharmacology , HIV Infections/metabolism , HIV-Associated Lipodystrophy Syndrome/chemically induced , Humans , Male , Middle Aged , Peptide Fragments/pharmacology , Tomography, X-Ray Computed , Waist Circumference/drug effects , Waist-Hip Ratio , Young Adult
4.
Ann Rheum Dis ; 69(2): 364-7, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19357113

ABSTRACT

OBJECTIVE: To determine the efficacy and safety of pamapimod in adult patients with active rheumatoid arthritis (RA) who had an inadequate clinical response to methotrexate (MTX). METHODS: Patients receiving stable doses of MTX were randomised to one of six dose groups and received 12 weeks of double-blind pamapimod (up to 300 mg once daily) or matching placebo. The primary efficacy measure was the proportion of patients with > or =20% improvement in RA based on the American College of Rheumatology criteria (ACR20) at 12 weeks. Secondary measures were ACR50, Disease Activity Score (DAS)/European League Against Rheumatism (EULAR) responses and the individual ACR core set of parameters. Safety measures included adverse events (AEs), laboratory testing and immunology assessments. RESULTS: On a background of MTX, the percentage of patients with an ACR20 response at week 12 in the pamapimod groups (31% to 43%) was not significantly different from placebo (34%). Secondary efficacy end points showed a similar pattern. AEs were typically mild and included infections, gastrointestinal disturbances, dizziness and rashes; AEs resulting in discontinuation of study drug were primarily attributed to infections. CONCLUSION: In patients with active RA receiving stable doses of MTX, pamapimod showed non-significant improvement in efficacy outcomes compared to placebo.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Methotrexate/therapeutic use , Pyridones/therapeutic use , Pyrimidines/therapeutic use , Adolescent , Adult , Aged , Antirheumatic Agents/adverse effects , Arthritis, Rheumatoid/blood , Biomarkers/blood , C-Reactive Protein/metabolism , Double-Blind Method , Drug Therapy, Combination , Humans , Methotrexate/adverse effects , Middle Aged , Protein Kinase Inhibitors/adverse effects , Protein Kinase Inhibitors/therapeutic use , Pyridones/adverse effects , Pyrimidines/adverse effects , Severity of Illness Index , Treatment Outcome , Young Adult , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors
5.
Onderstepoort J Vet Res ; 72(3): 207-17, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16300189

ABSTRACT

Seasonal surveys were conducted at the Vaal Dam between April 2000 and January 2001. Twenty smallmouth yellowfish (Labeobarbus aeneus) and 20 largemouth yellowfish (Labeobarbus kimberleyensis) were collected with the aid of gill nets. Surface water quality variables were included. The cestodes were identified as either Bothriocephalus acheilognathi Yamaguti, 1934 or "other cestode spp.". The majority (99.8%) of the cestodes found in both yellowfish species were identified as B. acheilognathi (Asian tapeworm). The prevalence, mean intensity and abundance of B. acheilognathi in both yellowfish species were calculated. Ecological parameters including species specificity, seasonality, gender specificity and relationships between fish size and the Asian tapeworm prevalence were also included. In this study, B. acheilognathi preferred L. kimberleyensis over L. aeneus although a low intensity was observed in smallmouth yellowfish. Furthermore, the infection (in terms of prevalence, abundance and mean intensity) in largemouth yellowfish was markedly higher. Seasonal patterns observed in the Asian tapeworm's infection of smallmouth yellowfish are attributed to breeding and subsequent feeding patterns of this fish species with relatively high infections recorded in winter and spring. For L. kimberleyensis no explanation can be given regarding the seasonal patterns observed for the mean intensity and abundance of B. acheilognathi. The maximum and minimum mean intensity and abundance values in largemouth yellowfish were recorded in autumn and spring, respectively. In addition, the prevalence of B. acheilognathi was consistently high in all four seasons.


Subject(s)
Cestoda/isolation & purification , Cestode Infections/veterinary , Fish Diseases/epidemiology , Animals , Cestoda/classification , Cestoda/growth & development , Cestode Infections/epidemiology , Cestode Infections/parasitology , Female , Fish Diseases/parasitology , Fishes , Male , Population Dynamics , Prevalence , Seasons , South Africa/epidemiology , Species Specificity
6.
Antimicrob Agents Chemother ; 39(2): 564-6, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7726536

ABSTRACT

Four spontaneous, single-step mutants of Escherichia coli K-12 resistant to low levels of the cephalosporin 3'-quinolone ester Ro 23-9424 were isolated at a frequency of 10(-10) to 10(-11) mutants per CFU plated. The mutants were cross-resistant to both cephalosporin (cefotaxime) and quinolone (fleroxacin) components. Accordingly, they had altered porins and replicative DNA biosynthesis resistant to fleroxacin. There was no increase in beta-lactamase activity when tested with nitrocephin, and the penicillin-binding protein profiles were normal.


Subject(s)
Anti-Infective Agents/pharmacology , Cefotaxime/analogs & derivatives , Escherichia coli/drug effects , Fleroxacin/analogs & derivatives , Fluoroquinolones , Cefotaxime/pharmacology , Drug Resistance, Microbial , Fleroxacin/pharmacology , Microbial Sensitivity Tests
7.
FEMS Microbiol Lett ; 108(2): 183-7, 1993 Apr 01.
Article in English | MEDLINE | ID: mdl-8387443

ABSTRACT

The lipopolysaccharide and porin profile of Escherichia coli ATCC 25922, a smooth strain commonly used in antibiotic susceptibility testing, and five isogenic rough mutants was examined. The lipopolysaccharide of the parent strain had the characteristic ladder pattern on polyacrylamide gels, while that of the mutants appeared similar to chemotypes Ra and Rc of Salmonella typhimurium with some changes in chemical composition. Of the porins, OmpC appeared markedly reduced in the parent strain while OmpF appeared markedly reduced in the mutants. In addition, a new outer-membrane protein of size intermediate to that of OmpC and OmpF was detected in all mutants. Neither parent nor mutants were susceptible to the LPS core-specific P1 phage or the porin-specific PA2 and K20 phages.


Subject(s)
Bacterial Outer Membrane Proteins/chemistry , Escherichia coli/chemistry , Escherichia coli/genetics , Lipopolysaccharides/chemistry , Bacterial Outer Membrane Proteins/genetics , Genes, Bacterial/genetics , Genetic Variation , Mutation , Porins
8.
Antimicrob Agents Chemother ; 37(3): 559-65, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8384817

ABSTRACT

Cephalosporin 3'-quinolone esters, carbamates, and tertiary amines are potent antibiotics whose antibacterial activities reflect the action of both the beta-lactam and the quinolone components. The biological properties of representative compounds from each class were compared in Escherichia coli. All compounds bound to the essential PBP 3, inhibited DNA gyrase, and caused filamentation in growing cells. To distinguish between cephalosporin- and quinolone-induced filaments, nucleoid segregation was also examined, as quinolones disrupt nucleoid segregation while the beta-lactams do not (N. H. Georgopapadakou and A. Bertasso, Antimicrob. Agents Chemother. 35:2645-2648, 1991). The cephalosporin quinolone esters Ro 23-9424 and Ro 24-6392, at concentrations causing filamentation in E. coli ATCC 25922, did not affect nucleoid segregation after 1 h of incubation (cephalosporin response) but did not affect it after 2 h (quinolone response), indicating the release of free quinolone. Accordingly, only the quinolone response was produced in a strain possessing TEM-3, an expanded-spectrum beta-lactamase. The cephalosporin carbamate Ro 24-4383 and the tertiary amine Ro 24-8138 produced a quinolone response in E. coli ATCC 25922, though they produced a cephalosporin response in a quinolone-resistant strain. Carbamate and tertiary amine linkages are chemically more stable than the ester linkage, and both cephalosporin 3'-quinolone carbamates and tertiary amines are more potent inhibitors of DNA gyrase than are the corresponding esters. The results suggest that, while intact cephalosporin 3'-quinolone esters act as cephalosporins, carbamates and amines may possess both cephalosporin and quinolone activity in the intact molecule.


Subject(s)
Anti-Infective Agents/pharmacology , Bacterial Proteins , Cephalosporins/pharmacology , Escherichia coli/drug effects , Hexosyltransferases , Peptidyl Transferases , Amines/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacokinetics , Carrier Proteins/metabolism , Cefotaxime/chemistry , Cefotaxime/pharmacokinetics , Cefotaxime/pharmacology , Ceftriaxone/chemistry , Ceftriaxone/pharmacokinetics , Ceftriaxone/pharmacology , Cell Nucleus/drug effects , Cephalosporins/chemistry , Cephalosporins/pharmacokinetics , Ciprofloxacin/chemistry , Ciprofloxacin/pharmacokinetics , Ciprofloxacin/pharmacology , Escherichia coli/growth & development , Muramoylpentapeptide Carboxypeptidase/metabolism , Penicillin-Binding Proteins , Structure-Activity Relationship , Topoisomerase II Inhibitors
10.
Antimicrob Agents Chemother ; 36(8): 1601-5, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1416840

ABSTRACT

The accumulation of quinolones by Escherichia coli JF568, Pseudomonas aeruginosa PAO1, and Staphylococcus aureus ATCC 29213 was measured by a modified fluorometric assay (J. S. Chapman and N. H. Georgopapadakou, Antimicrob. Agents Chemother. 33:27-29, 1989). The quinolones examined were fleroxacin, pefloxacin, norfloxacin, difloxacin, A56620, ciprofloxacin, ofloxacin, and Ro 09-1168. In all three organisms, uptake was complete in less than 5 min and was proportional to extracellular quinolone concentrations between 2 and 50 micrograms/ml, which is consistent with simple diffusion. Washing cells with quinolone-free buffer decreased accumulation by up to 70% in E. coli and P. aeruginosa but not in S. aureus. Similarly, incubation with the uncouplers 2,4-dinitrophenol and carbonyl cyanide m-chlorophenylhydrazone increased accumulation up to fourfold in E. coli and P. aeruginosa, though not in S. aureus, suggesting endogenous, energy-dependent efflux. High quinolone hydrophobicity was generally associated with decreased accumulation in E. coli and P. aeruginosa (except in the case of pefloxacin) but was associated with increased accumulation in S. aureus (except in the case of difloxacin). Ciprofloxacin had the highest accumulation in E. coli and P. aeruginosa, while pefloxacin had the highest accumulation in S. aureus.


Subject(s)
Anti-Infective Agents/metabolism , Escherichia coli/metabolism , Pseudomonas aeruginosa/metabolism , Staphylococcus aureus/metabolism , 4-Quinolones , Anti-Infective Agents/chemistry , Chemical Phenomena , Chemistry, Physical
11.
Antimicrob Agents Chemother ; 36(8): 1779-81, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1416865

ABSTRACT

The relationship between sterol biosynthesis inhibition, membrane integrity, and cell growth inhibition in Candida albicans was examined for five squalene epoxidase inhibitors. The compounds were the thiocarbamates tolnaftate and tolciclate and the allylamines naftifine, terbinafine, and SDZ 87-469. All compounds inhibited sterol biosynthesis, with the concentrations that caused a 50% decrease in the total sterol-to-squalene ratio ranging from less than or equal to 0.01 microM for terbinafine and SDZ 87-469 to 500 microM for tolnaftate. At 100 microM, the compounds also caused up to a 30% release of intracellular [14C]aminoisobutyric acid. With terbinafine and SD2 87-469, aminoisobutyric acid release further increased in cells grown at concentrations that inhibited ergosterol biosynthesis. It is suggested that inhibition of ergosterol synthesis may render the C. albicans membrane susceptible to further damage, including direct damage from squalene epoxidase inhibitors.


Subject(s)
Antifungal Agents/pharmacology , Candida albicans/drug effects , Oxygenases/antagonists & inhibitors , Candida albicans/growth & development , Candida albicans/metabolism , Cell Membrane/drug effects , Microbial Sensitivity Tests , Squalene Monooxygenase , Sterols/biosynthesis
12.
Antimicrob Agents Chemother ; 35(12): 2645-8, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1810201

ABSTRACT

The effects of quinolone antibiotics on nucleoid segregation in growing Escherichia coli were examined by using fleroxacin (Ro 23-6240, AM 833) as a prototype compound. At levels that were close to its MIC and induced growth arrest and filamentation, fleroxacin caused large nucleoids to appear in midcell, suggesting inhibition of nucleoid segregation. With increasing fleroxacin concentrations, nucleoids became progressively smaller, suggesting inhibition of DNA replication. Removal of fleroxacin restored normal cell and nucleoid morphology in filaments with large nucleoids but not in filaments with small nucleoids. The results are consistent with inhibition of chromosome decatenation at low quinolone concentrations (bacteriostatic effect) and DNA supercoiling at high concentrations (bactericidal effect).


Subject(s)
Anti-Infective Agents/pharmacology , DNA, Bacterial/drug effects , Escherichia coli/drug effects , Aztreonam/analogs & derivatives , Aztreonam/pharmacology , Cell Nucleus/drug effects , DNA, Bacterial/biosynthesis , Dose-Response Relationship, Drug , Escherichia coli/growth & development , Fleroxacin/pharmacology , Photomicrography
13.
Antimicrob Agents Chemother ; 35(5): 910-5, 1991 May.
Article in English | MEDLINE | ID: mdl-1649574

ABSTRACT

Ro 23-9424 is a broad-spectrum antibacterial agent consisting of a cephalosporin (desacetylcefotaxime) linked through an ester bond to a fluoroquinolone (fleroxacin). Its activity against mutants of Escherichia coli TE18 resistant to both antibacterial components was examined. E. coli TE18 overproduces the AmpC beta-lactamase and is resistant to several cephalosporins, including desacetylcefotaxime (MIC, 50 micrograms/ml), although it is still susceptible to Ro 23-9424 (MIC, 0.2 microgram/ml). Thirty-five spontaneous, two-step mutants of E. coli TE18 which were resistant to fleroxacin (MIC, 50 micrograms/ml) were isolated. In the mutants, replicative DNA biosynthesis (permeabilized cells) was resistant to fleroxacin, and some mutants had porin abnormalities. However, all remained susceptible to Ro 23-9424 (MIC, 0.5 microgram/ml). Examination of beta-lactamase activity in the parent strain revealed that it hydrolyzes desacetylcefotaxime more rapidly than it does Ro 23-9424. Thus, Ro 23-9424 may be less susceptible to the gram-negative, chromosomal beta-lactamases that hydrolyze several broad-spectrum cephalosporins and may be effective in cases in which neither of its two components is active.


Subject(s)
Anti-Infective Agents/pharmacology , Bacterial Proteins , Cefotaxime/analogs & derivatives , Cephalosporins/pharmacology , Ciprofloxacin/analogs & derivatives , Escherichia coli/drug effects , Fluoroquinolones , Hexosyltransferases , Peptidyl Transferases , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/metabolism , Bacterial Outer Membrane Proteins/biosynthesis , Bacterial Outer Membrane Proteins/genetics , Carrier Proteins/genetics , Cefotaxime/pharmacology , Cell Membrane Permeability/physiology , Ciprofloxacin/pharmacology , Coliphages , DNA Replication , DNA, Bacterial/biosynthesis , Drug Resistance, Microbial , Escherichia coli/genetics , Escherichia coli/metabolism , Fleroxacin , Gene Expression Regulation, Bacterial , Microbial Sensitivity Tests , Muramoylpentapeptide Carboxypeptidase/genetics , Mutation , Penicillin-Binding Proteins , Porins , beta-Lactamases/genetics
14.
Antimicrob Agents Chemother ; 33(7): 1067-71, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2675755

ABSTRACT

Ro 23-9424 is a broad-spectrum antibacterial agent composed of a cephalosporin and a quinolone moiety. Its biological properties were compared with those of its two components and structurally related cephalosporins and quinolones. Like ceftriaxone and cefotaxime but unlike its decomposition product, desacetyl cefotaxime, Ro 23-9424 bound at less than or equal to 2 micrograms/ml to the essential penicillin-binding proteins 1b and 3 of Escherichia coli and 1, 2, and 3 of Staphylococcus aureus. In E. coli, Ro 23-9424 produced filaments exclusively and decreased cell growth; cefotaxime produced both filaments and lysis. Like its decomposition product fleroxacin but unlike quinolone esters, Ro 23-9424 also inhibited replicative DNA biosynthesis in E. coli. In an E. coli strain lacking OmpF, growth continued after addition of Ro 23-9424, decreased after addition of cefotaxime, and stopped immediately after addition of fleroxacin. The results, together with the chemical stability of Ro 23-9424 (half-life, approximately 3 h at pH 7.4 and 37 degrees C), suggest that in E. coli the compound acts initially as a cephalosporin with intrinsic activity comparable to that of cefotaxime but with poorer penetration. Subsequent to the decomposition of Ro 23-9424 to fleroxacin and desacetyl cefotaxime, quinolone activity appears. The in vitro antibacterial activity reflects both mechanisms of action.


Subject(s)
Bacterial Proteins , Cefotaxime/analogs & derivatives , Cephalosporins/pharmacology , Ciprofloxacin/analogs & derivatives , Fleroxacin/analogs & derivatives , Fluoroquinolones , Hexosyltransferases , Peptidyl Transferases , Anti-Infective Agents/pharmacology , Carrier Proteins/metabolism , Cefotaxime/pharmacology , Ciprofloxacin/pharmacology , DNA Replication/drug effects , DNA, Bacterial/biosynthesis , Enterobacter/drug effects , Enterobacter/metabolism , Escherichia coli/drug effects , Escherichia coli/metabolism , Microbial Sensitivity Tests , Muramoylpentapeptide Carboxypeptidase/metabolism , Penicillin-Binding Proteins , Staphylococcus aureus/drug effects , Staphylococcus aureus/metabolism , beta-Lactamases/metabolism
15.
Antimicrob Agents Chemother ; 33(2): 239-41, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2541657

ABSTRACT

Spontaneous fleroxacin-resistant mutants of Escherichia coli K-12 were isolated at a frequency of 10(-10) to 10(-11) mutants per CFU plated. All mutants exhibited quinolone-resistant replicative DNA biosynthesis, and 4 of 11 mutants also had decreased amounts of OmpF or OmpC porin. None of the mutants had changes solely in porin proteins.


Subject(s)
Anti-Bacterial Agents/pharmacology , Ciprofloxacin/analogs & derivatives , Escherichia coli/drug effects , Bacterial Outer Membrane Proteins/analysis , Bacterial Outer Membrane Proteins/biosynthesis , Ciprofloxacin/pharmacology , DNA Topoisomerases, Type II/metabolism , DNA, Bacterial/biosynthesis , Drug Resistance, Microbial , Electrophoresis, Polyacrylamide Gel , Escherichia coli/metabolism , Fleroxacin , Microbial Sensitivity Tests
16.
Exp Eye Res ; 46(6): 871-80, 1988 Jun.
Article in English | MEDLINE | ID: mdl-3197757

ABSTRACT

The rhesus monkey lens exhibits two zones of discontinuity, one anteriorly and one posteriorly. They are first discernible by slit-lamp photography as performed in this study at around age 7 years in iridectomized eyes, and become more distinct with increasing age. Their thickness and distance from each other along the polar axis are independent of lens age, but their distance from the lens surface increases with increasing age. Upon accommodation, the distance between the two zones increases while all other distances along the polar axis remain unchanged, indicating that, as in the human, overall alterations in rhesus lenticular shape and thickness with accommodation primarily reflect changes in the shape of the central region. The curvature of each zone becomes sharper in a linear fashion with accommodation, with the slope of the relationship being similar to those for lens surfaces.


Subject(s)
Lens, Crystalline/physiology , Accommodation, Ocular , Aging/pathology , Animals , Light , Macaca mulatta , Scattering, Radiation
17.
Exp Eye Res ; 45(2): 317-26, 1987 Aug.
Article in English | MEDLINE | ID: mdl-3653294

ABSTRACT

Changes in crystalline lens shape and axial thickness, anterior chamber depth and anterior cornea-posterior lens distance during accommodation induced by corneal iontophoresis of carbachol or electrical stimulation of the Edinger-Westphal nucleus were studied in 25 living, surgically aniridic rhesus monkey eyes, aged 1-25 years. Intraocular distances and anterior and posterior lens surface curvatures were evaluated from slit-lamp Scheimpflug photographs; distances were also determined by A-scan ultrasonography. With increasing accommodation, both lens surfaces become more sharply curved, the lens thickens and the anterior chamber shallows, while the posterior lens surface remains fixed relative to the cornea. Within statistical limits, the respective curvature and distance changes are the same for a given dioptric accommodation induced by either stimulation technique. The respective intraocular distance-accommodation relationships are identical whether derived from photographic or ultrasonographic measurements. Temporal and contralateral reproducibility of all measurements is excellent. Each parameter-accommodation relationship is strikingly linear in all eyes, although above 20 D the slopes of the lens surface curvature-accommodation relationships may have decreased. The curvature change per D of accommodation averages approximately 20% more for the posterior than for the anterior lens surface. There is relatively little interindividual variation in the slope of each relationship despite the significant interindividual differences in age and accommodative amplitude, indicating that the relationships are independent of age. However, when extrapolated back to the non-accommodated resting state, the data indicate that the lens thickens, both its surfaces become more sharply curved, and the anterior chamber shallows with age in adult greater than 5 years, while opposite trends are seen in younger animals.


Subject(s)
Accommodation, Ocular , Aging/physiology , Anterior Chamber/physiology , Lens, Crystalline/physiology , Accommodation, Ocular/drug effects , Animals , Carbachol/pharmacology , Electric Stimulation , Female , Humans , Macaca mulatta , Male , Refraction, Ocular
18.
Exp Eye Res ; 44(2): 307-18, 1987 Feb.
Article in English | MEDLINE | ID: mdl-3582515

ABSTRACT

Slit-lamp photographic studies of 144 caged rhesus monkeys, aged 2 months to 35 years, show age-related changes in anterior-chamber depth, lens thickness, anterior and posterior curvatures of the lens, and location of the posterior lens surface relative to the anterior corneal surface. For these parameters, as well as for those measured by other techniques, a difference in slope magnitude and (or) slope sign was found between the growth phase which lasts for 5-6 years, and the adult phase (greater than 5-6 years). Age-related changes in the adult rhesus eye are qualitatively similar in almost all aspects to those observed in the human eye, indicating that the rhesus is a good animal model for the study of human loss of accommodative amplitude.


Subject(s)
Anterior Eye Segment/anatomy & histology , Lens, Crystalline/anatomy & histology , Aging , Animals , Anterior Chamber/anatomy & histology , Biometry , Cornea/anatomy & histology , Female , Macaca mulatta , Male
19.
Biophys J ; 37(2): 433-40, 1982 Feb.
Article in English | MEDLINE | ID: mdl-6895856

ABSTRACT

The aggregation properties of column-purified rabbit skeletal myosin at pH 7.0 were investigated as functions of ionic strength, protein concentration, and time. Filaments prepared by dialysis exhibited the same average length and population distribution at 0.10 and 0.15 M KCl at protein concentrations greater than 0.10 mg/ml; similar results were obtained at .0.20 M KCl, although average filament length was approximately 0.5 micrometer shorter. Once formed, these length distributions remained virtually unchanged over an 8-d period. At and below 0.10 mg/ml, average filament length decreased as a function of protein concentration; filaments prepared from an initial concentration of 0.02 mg/ml were half the length of those prepared at 0.2 mg/ml. Filaments prepared by dilution exhibited a sharp increase in average length as the time-course increased up to 40 s, then altered only slightly over a further period of 4 min. Addition of C-protein in a molar ratio of 1-3.3 myosin molecules affected most of these results. Average filament length was affected neither by ionic strength nor by initial protein concentration down to 0.04 mg/ml or over an 8-d period. Filaments formed by dilution in the presence of C-protein exhibited a constant average length and hypersharp length distribution over variable time courses up to 7 min. It is possible that C-protein acts to stabilize the antiparallel intermediate during filamentogenesis, and may also affect subunit addition to this nucleus.


Subject(s)
Muscle Proteins/metabolism , Muscles/anatomy & histology , Myosins/metabolism , Animals , Carrier Proteins , Dialysis , Hydrogen-Ion Concentration , Microscopy, Electron , Nephelometry and Turbidimetry , Osmolar Concentration , Potassium Chloride/metabolism , Rabbits , Time Factors
20.
Cancer Res ; 40(3): 634-41, 1980 Mar.
Article in English | MEDLINE | ID: mdl-6937240

ABSTRACT

Human embryonic lung fibroblasts (F-136-35-56) capable of growing in medium containing DL-homocysteine instead of L-methionine and human acute lymphoblastic leukemia cells (CCRF-HSB-2) with absolute methionine requirement exhibited dose-dependent growth inhibition when semipurified L-methionine-degrading enzyme (L-methioninase, EC 4.4.1.11) was added to the tissue cultures. When D-homocystine was added to the cultures together with L-methioninase (0.1 units/ml, which completely degraded the available L-methionine in tissue culture), the F-136-35-56 cells continued to grow whereas the CCRF-HSB-2 cells were completely inhibited. In mixed cultures of the two cell lines with added L-methioninase + D-homocystine or L-methioninase + L-homocysteine thiolactone, the normal fibroblasts grew and synthesized DNA vigorously, whereas the lymphocytic malignant cells lost their viability completely and died within 3 to 4 days.


Subject(s)
Leukemia, Lymphoid/metabolism , Methionine/metabolism , Carbon-Sulfur Lyases/metabolism , Cell Division , Cell Line , Homocystine/metabolism , Humans , Neoplasm Proteins/metabolism , Neoplasms, Experimental/metabolism
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