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1.
Osteoarthr Cartil Open ; 1(3-4): 100017, 2020.
Article in English | MEDLINE | ID: mdl-36475004

ABSTRACT

Objective: Fluorescence Optical Imaging (FOI) demonstrates indocyanine green (ICG)-enhanced microcirculation in wrist and finger joints, as a sign of inflammation. We wanted to assess the reliability of three FOI scoring methods from Berlin, Stockholm, and Copenhagen, to assess the validity of FOI with MRI as reference and to compare enhancement in hand joints in erosive hand osteoarthritis (OA) vs. rheumatoid arthritis (RA). Design: Five readers scored all finger and wrist joints of 26 patients with erosive hand OA and RA on semi-quantitative 0-3 scales using three different FOI scoring methods. To evaluate inter-reader reliability, we calculated the intraclass correlation coefficients (ICC) for sum scores and prevalence and bias adjusted kappa values for ordinal scales (Pabak-OS) on joint level. Enhancement in joint groups in erosive hand OA vs. RA was compared using Mann-Whitney test. Sensitivities and specificities of FOI was calculated with MRI as reference for hand OA patients only. Results: We found moderate to good inter-reader reliability for all FOI scoring methods (Pabak-OS: 0.50-0.78, ICC: 0.43-0.85) and different patterns of enhancement in erosive hand OA vs. RA with significantly more FOI enhancement in DIP joints in erosive hand OA across all methods. With MRI as reference the different FOI scoring methods reached similar sensitivities (63-65%) and specificities (76-91%). Conclusion: FOI enhancement can be measured reliably in erosive hand OA and RA using three different scoring methods. More DIP enhancement in erosive hand OA patients and good agreement with MRI support the diagnostic performance of FOI.

2.
Food Chem ; 271: 488-496, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-30236707

ABSTRACT

The capabilities of dynamic headspace entrainment followed by thermal desorption in combination with gas chromatography (GC) coupled to single quadrupole mass spectrometry (MS) have been tested for the determination of volatile components of olive oil. This technique has shown a great potential for olive oil quality classification by using an untargeted approach. The data processing strategy consisted of three different steps: component detection from GC-MS data using novel data treatment software PARADISe, a multivariate analysis using EZ-Info, and the creation of the statistical models. The great number of compounds determined enabled not only the development of a quality classification method as a complementary tool to the official established method "PANEL TEST" but also a correlation between these compounds and different types of defect. Classification method was finally validated using blind samples. An accuracy of 85% in oil classification was obtained, with 100% of extra virgin samples correctly classified.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Olive Oil/chemistry , Volatile Organic Compounds/analysis , Mass Spectrometry , Multivariate Analysis , Plant Oils , Sensation
3.
Lupus ; 27(1): 33-39, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28385125

ABSTRACT

Objective The aim of this study was to measure presenteeism (productivity impairment while the patient is at work) and the related risk factors in patients with systemic lupus erythematosus (SLE) from Argentina. Methods A total of 130 consecutive (1997 American College of Rheumatology (ACR) criteria) working patients with SLE were assessed using a standardized data collection form. Sociodemographic, disease and work-related variables were collected. The Work Productivity and Activity Impairment (WPAI) questionnaire was performed. Results Overall, 130 patients were included in the analysis; 91% were women, and the mean age was 39 years (range 19-77). A total of 43% were White, 43% Mestizo and 13% Amerindian. Overall, 38% were single and 38% were married. A total of 75% had more than 12 years of formal education. The median disease duration was 7 years (interquartile range 25-75 (IQR) 4-13). Median Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score was 0 (IQR 0-2), and median Systemic Lupus International Collaborating Clinics/ACR Damage Index (SLICC-SDI) score was 0 (IQR 0-1). Lupus quality of life (LupusQoL) domains scores were: physical health 87 (IQR 70-96), emotional health 78 (IQR 54-91), burden to others 75 (IQR 50-92), intimate relationships 87 (IQR 50-100), and body image 85 (IQR 70-100). Absenteeism was 8%, presenteeism was 19%, and overall work impairment (absenteeism + presenteeism) was 26%. In the multiple regression analysis, considering presenteeism as dependent variable, (adjusting by age, disease duration, >12 years of education, Non-white race, Visual Analogue Scale (VAS) pain, VAS fatigue, SLICC-SDI, LupusQoL, physical and emotional domains), we found that SLICC-SDI (odds ratio (OR) 1.68, confidence interval (CI) 1-2.7) and Non-white race (OR 3.27, CI 1.04-10) were related to presenteeism and >12 years of education (OR 0.30, CI 0.09-0.98) and higher scores of LupusQoL emotional health domain (OR 0.95, CI 0.92-0.98) were protective. Conclusions organ damage and Non-white race were significantly associated with presenteeism while >12 years of education and higher scores of LupusQoL emotional health domain were protective.


Subject(s)
Lupus Erythematosus, Systemic/psychology , Work Performance/statistics & numerical data , Adult , Aged , Argentina/epidemiology , Cross-Sectional Studies , Female , Humans , Lupus Erythematosus, Systemic/epidemiology , Male , Middle Aged , Young Adult
4.
Eat Weight Disord ; 17(1): e70-7, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22751276

ABSTRACT

BACKGROUND/AIM: In order to get more detailed information about exercise regimes and disturbances among patients with eating disorders, a new self report questionnaire was developed. The Exercise and Eating Disorders (EED) was developed to capture aspects not included in existing questionnaires. The aim of this study was to test the internal consistency and concurrent validity of the EED, and to investigate to what extent the questionnaire discriminates between inpatients and controls. METHOD: Fifty female eating disorder patients (anorexia nervosa n=25, bulimia nervosa n=10, EDNOS n=15) in a specialized inpatient unit and 51 female age-matched student controls were assessed with the EED and the Body Attitude Test (BAT). RESULTS: The results indicate satisfactory internal consistency (Cronbach's Alpha 0.92) of the sum score of the whole sample. The validity of the EED was supported by the correlation analysis between EED and Body Attitude Test (BAT) (Spearman's rho=0.84, p<0.01). There was a significant statistical difference between patients and controls in total score and subscales of the EED (p<0.001). CONCLUSION: The preliminary test of the EED questionnaire was promising. It is a short instrument, and seems to distinguish well between patients and controls. EED captures other dimensions of physical activity and exercise disturbances not captured in other questionnaires related to exercise. Further research is needed to test the psychometric properties of EED in bigger samples.


Subject(s)
Anorexia Nervosa/diagnosis , Behavior, Addictive/diagnosis , Bulimia Nervosa/diagnosis , Exercise , Feeding and Eating Disorders/diagnosis , Adolescent , Adult , Anorexia Nervosa/physiopathology , Behavior, Addictive/physiopathology , Bulimia Nervosa/physiopathology , Case-Control Studies , Female , Humans , Inpatients , Pilot Projects , Psychometrics/instrumentation , Reproducibility of Results , Surveys and Questionnaires
5.
Plasmid ; 58(2): 115-26, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17395262

ABSTRACT

The complete nucleotide sequence of pEOC01, a plasmid (11,661 bp) from Pediococcus acidilactici NCIMB 6990 encoding resistance to clindamycin, erythromycin, and streptomycin was determined. The plasmid, which also replicates in Lactococcus and Lactobacillus species contains 16 putative open reading frames (ORFs), including regions annotated to encode replication, plasmid maintenance and multidrug resistance functions. Based on an analysis the plasmid replicates via a theta replicating mechanism closely related to those of many larger Streptococcus and Enterococcus plasmids. Interestingly, genes homologous to a toxin/antitoxin plasmid maintenance system are present and are highly similar to the omega-epsilon-zeta operon of Streptococcus plasmids. The plasmid contains two putative antibiotic resistance homologs, an ermB gene encoding erythromycin and clindamycin resistance, and a streptomycin resistance gene, aadE. Of particular note is the aadE gene which holds 100% identity to an aadE gene found in Campylobacter jejuni plasmid but which probably originated from a Gram-positive source. This observation is significant in that it provides evidence for recent horizontal transfer of streptomycin resistance from a lactic acid bacterium to a Gram-negative intestinal pathogen and as such infers a role for such plasmids for dissemination of antibiotic resistance genes possibly in the human gut.


Subject(s)
Campylobacter jejuni/genetics , Drug Resistance, Multiple, Bacterial/genetics , Genes, Bacterial , Pediococcus/genetics , Plasmids/genetics , Base Sequence , Chromosome Mapping , Chromosomes, Bacterial , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Molecular Sequence Data , Open Reading Frames , Phylogeny , Plasmids/drug effects , Plasmids/isolation & purification , Repetitive Sequences, Nucleic Acid , Replication Origin , Sequence Analysis, DNA , Streptomycin/pharmacology
7.
J Appl Microbiol ; 102(2): 384-9, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17241343

ABSTRACT

AIM: To investigate the susceptibility of Pediococcus species to antimicrobial agents. METHODS AND RESULTS: The susceptibility to 14 antimicrobial agents of 31 genotypically distinct strains of six Pediococcus species was assessed by using Etests on ISO-sensitest agar supplemented with horse blood. The species included were Pediococcus acidilactici, Pediococcus damnosus, Pediococcus dextrinicus, Pediococcus inopinatus, Pediococcus parvulus and Pediococcus pentosaceus. For several antimicrobial agents, some species were more susceptible than others. The two industrially important species, P. acidilactici and P. pentosaceus, differed with respect to erythromycin and trovafloxacin susceptibility, and in general both species had higher minimum inhibitory concentrations than the other species. In an erythromycin-resistant P. acidilactici, an erythromycin resistance methylase B [erm(B)] gene was identified by PCR. Using a plasmid preparation from strain P. acidilactici 6990, a previously erythromycin-sensitive Lactococcus lactis strain was made resistant. Transformants harboured a single plasmid, sized at 11.6 kb through sequence analysis. In addition, the erm(B) gene was identified within the plasmid sequence. CONCLUSIONS: The phenotypic test indicated the absence of acquired antimicrobial resistance genes in 30 of the strains. SIGNIFICANCE AND IMPACT OF THE STUDY: These results will help in selection of the best Pediococcus strains for use as starter cultures.


Subject(s)
Anti-Infective Agents/pharmacology , Industrial Microbiology , Pediococcus/drug effects , Bacteriological Techniques , DNA Fingerprinting , Drug Resistance, Bacterial , Microbial Sensitivity Tests , Microbial Viability/drug effects , RNA, Ribosomal, 16S/analysis , Species Specificity
8.
Lett Appl Microbiol ; 38(3): 206-10, 2004.
Article in English | MEDLINE | ID: mdl-14962041

ABSTRACT

AIM: Lactobacilli have been reported to have intrinsic resistance to trimethoprim. The susceptibility of lactobacilli to trimethoprim on different media was investigated in order to search for a phenotypic test method that could indicate the presence of acquired resistance genes. METHODS AND RESULTS: Strains of Lactobacillus acidophilus, Lact. paracasei, Lact. rhamnosus and Lact. plantarum were susceptibility tested with E-tests on folic acid casei medium (FACM), MRS and defined medium 1. The effects of addition or removal of nucleosides and thymidine phosphorylase were investigated. E-tests on FACM yielded reproducible minimal inhibitory concentrations (MICs) for trimethoprim but addition of nucleosides was necessary for growth of Lact. acidophilus. MICs for the tested strains were 0.125-0.19, 0.25-3 and 0.064-0.19 microg ml(-1) for Lact. paracasei, Lact. rhamnosus and Lact. plantarum, respectively. With the addition of deoxyuridine and deoxyadenosine to FACM the MICs of Lact. acidophilus were 0.064-1 microg ml(-1). CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacilli do not have intrinsic resistance to trimethoprim. The results show that trimethoprim susceptibility testing of the tested Lactobacillus species is possible and indicate that transferable resistance genes are absent in all the tested strains.


Subject(s)
Culture Media/chemistry , Lactobacillus/drug effects , Microbial Sensitivity Tests/methods , Trimethoprim/pharmacology , Anti-Infective Agents/pharmacology , Deoxyribonucleosides/metabolism , Drug Resistance, Bacterial/genetics , Folic Acid/metabolism , Folic Acid Antagonists/pharmacology , Lactobacillus/genetics , Lactobacillus/growth & development , Thymidine Phosphorylase/metabolism , Thymine/metabolism
9.
J Theor Biol ; 222(3): 337-46, 2003 Jun 07.
Article in English | MEDLINE | ID: mdl-12732480

ABSTRACT

Recently, a mathematical model of the pumping heart has been proposed describing the heart as a pressure source depending on time, volume and flow. The underlying concept is based on a new two-step paradigm that allows separation between isovolumic (non-ejecting) and ejecting heart properties. The first step describes the ventricular pressure in the isovolumic ventricle. In the following step, the isovolumic description is extended with the ejection effect in order to embrace the pumping heart during actual blood ejection. The description of the isovolumic heart properties plays a crucial role in this paradigm. However, only a single isovolumic model has previously been used restricting the heart rate to 1 Hz. In this paper, a family of models describing the isovolumic contracting ventricle are critically examined. A characterization of what constitutes an optimal model is given and used as a criteria for choosing the optimal model in this family. Moreover, and this is indeed a point, the proposed model in this study is valid for arbitrary heart rates and based on experimental data. The model exhibits all major features of the ejecting heart, including how ventricular pressure and flow vary in time for various heart rates and how stroke volume and cardiac output vary with heart rate. The modeling strategy presented embraces the same steps and demarcations as those suitable for clinical examination whereby new experiments are suggested.


Subject(s)
Heart Rate/physiology , Models, Cardiovascular , Myocardial Contraction/physiology , Cardiac Output/physiology , Humans , Stroke Volume/physiology , Ventricular Function
10.
J Recept Signal Transduct Res ; 21(1): 71-84, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11693174

ABSTRACT

Chloramphenicol acetyltransferase (CAT) is widely used as a reporter to determine the transcriptional specificity of promoters and for the quantification of transcriptional activity of transcription factors such as nuclear receptors. However, large-scale quantification of CAT activity in transfected mammalian cells is still heavily labor-intensive, time-consuming and expensive. Here, we describe a simplified method that combined using multiwell tissue culture plates in transfection and sample preparation and a modified single step method for quantitatively assaying CAT activity. By using multiwell plates, the tedious sample preparation procedure was dramatically simplified. The CAT assay is performed by mixing cell lysate, chloramphenicol, 3H-acetyl co-enzyme A and non-aqueous scintillation fluid in scintillation vials, followed by automatically continuously counting samples two or three cycles at fixed time intervals. The catalytic reaction and determination of CAT activity are carried out in the vials simultaneously. This simplified protocol is faster, less expensive and more accurate than other CAT assay procedures and the results can be normalized easily. The utility of the assay is demonstrated by the analysis of the transcriptional activity of the glucocorticoid and androgen receptors cotransfected into cells with a CAT reporter.


Subject(s)
Chloramphenicol O-Acetyltransferase/analysis , Chloramphenicol O-Acetyltransferase/genetics , Receptors, Androgen/genetics , Receptors, Glucocorticoid/genetics , Transcription, Genetic , Animals , CHO Cells , COS Cells , Cell Line , Cricetinae , Dexamethasone/pharmacology , Genes, Reporter , Mice , Mutation , Progesterone/pharmacology , Scintillation Counting/methods , Transfection
13.
J Theor Biol ; 212(1): 71-81, 2001 Sep 07.
Article in English | MEDLINE | ID: mdl-11527446

ABSTRACT

The pumping heart is described by a new mathematical approach which considers the heart as a pressure source depending on time, volume and flow. This new approach allows a separation between isovolumic (non-ejecting) and ejecting heart properties. The computed results cover most of the features of the human ventricle during normal and altered vascular conditions. It is shown that the time-varying elastance concept is disqualified as an independent description of the heart, it follows from isovolumic heart properties and an ejection effect which consists of positive and negative effects of ventricular blood ejection.


Subject(s)
Heart/physiology , Models, Cardiovascular , Animals , Humans , Pressure , Stroke Volume/physiology , Vascular Resistance/physiology , Ventricular Function
14.
Stud Health Technol Inform ; 71: 13-28, 2000.
Article in English | MEDLINE | ID: mdl-10977595

ABSTRACT

A recently developed model of the left ventricle, based on experimental data, has been shown to exhibit the main features of the heart's ability to pump. Two special cases during blood ejection, termed pressure deactivation and hyperactivation, were identified. This study proposes an 'ejection effect' correction to the model that addresses deactivation, hyperactivation and adjusts the shape of the computed ventricular ejection curve in late systole. Also, a new approach based on new animal experiments is proposed to identify the ejection effect mechanism(s).


Subject(s)
Models, Cardiovascular , Stroke Volume/physiology , Ventricular Function, Left/physiology , Animals , Humans , Mathematics , Ventricular Pressure/physiology
15.
Exp Cell Res ; 260(1): 160-5, 2000 Oct 10.
Article in English | MEDLINE | ID: mdl-11010820

ABSTRACT

Inhibition of the ligand-activated androgen receptor (AR) by antiandrogens plays an important role in the treatment of various hyperandrogenic disorders including prostate cancer. However, the molecular mechanisms of antiandrogen activity in vivo remain unclear. In this study we analyzed the effects of cyproterone acetate (CPA), flutamide (F), and hydroxyflutamide (OHF) on transcriptional activation and chromatin remodeling of the genomically integrated mouse mammary tumor virus (MMTV) promoter. This promoter has provided an excellent model system to study the impact of steroid hormones on transcriptional activation in the context of a defined chromatin structure. The MMTV hormone response element is positioned on a phased nucleosome, which becomes remodeled in response to steroids. We utilized this model system in mouse L-cell fibroblasts that contain a stably integrated MMTV promoter. In these cells, dihydrotestosterone (DHT) induced a large increase of AR protein levels that correlated with transcriptional activation and chromatin remodeling of the MMTV promoter. Coadministration of DHT and CPA or DHT and OHF in these cells inhibited the increase of AR levels, which resulted in a strong blockage of transcriptional activation and chromatin remodeling of the MMTV promoter. In contrast, F had no significant influence on these activities. We conclude that a major portion of the antiandrogenic effects of CPA and OHF in vivo are mediated by the reduction of AR levels.


Subject(s)
Androgen Antagonists/pharmacology , Chromatin/drug effects , Mammary Tumor Virus, Mouse/drug effects , Mammary Tumor Virus, Mouse/genetics , Promoter Regions, Genetic/drug effects , Animals , Base Sequence , Cyproterone Acetate/pharmacology , DNA Probes/genetics , Female , Flutamide/analogs & derivatives , Flutamide/pharmacology , L Cells , Male , Mice , Receptors, Androgen/drug effects , Receptors, Androgen/metabolism , Transcriptional Activation/drug effects
16.
Mutat Res ; 448(1): 47-55, 2000 Mar 14.
Article in English | MEDLINE | ID: mdl-10751622

ABSTRACT

Owing to occasional spontaneous mutations in genes encoding DNA repair, any population of a reasonable size is expected to harbor a sub-population of genetic mutators. Using a genetically modified strain of Escherichia coli K-12, we have estimated the frequency of mutators to be about 3x10(-5). By and large, this corresponds to a mutation rate from non-mutators to mutators of 5x10(-6) per bacterium per generation. Using a mutS∷Tn10 derivative as representative for mutators, we estimated the increase in mutation rates in mutators to be 19- to 82-fold, depending on the test-mutation under consideration. The load associated with this increase in mutation rate resulted in a growth inhibition of 1%. From these data, we estimated that the rate of detrimental mutations in the non-mutators to be 2x10(-4)-8x10(-4). The situations where adaptive mutations may result in an increase in the frequency of mutators are discussed.


Subject(s)
Adenosine Triphosphatases , Bacterial Proteins/genetics , DNA-Binding Proteins , Escherichia coli Proteins , Escherichia coli/genetics , Genetics, Population , Mutation , Cell Division/genetics , Culture Media , DNA Repair/genetics , Escherichia coli/metabolism , Gene Frequency , Lac Repressors , Lactose/metabolism , MutS DNA Mismatch-Binding Protein , Repressor Proteins/genetics , Selection, Genetic
17.
Exp Cell Res ; 252(2): 471-8, 1999 Nov 01.
Article in English | MEDLINE | ID: mdl-10527637

ABSTRACT

The integrated mouse mammary tumor virus (MMTV) promoter has provided an excellent model system with which to study the impact of steroid hormones on transcriptional activation in the context of a defined chromatin structure. The hormone response element (HRE) of this promoter is positioned on a phased nucleosome which becomes remodeled in response to steroids. One possible mechanism of chromatin remodeling by steroid receptors could involve recruitment of coactivators which alter the histone acetylation status of the HRE nucleosome. To examine how the androgen receptor (AR) influences transcription and chromatin remodeling and to assess whether changes in histone acetylation are involved in these effects, we determined whether the specific histone deacetylase inhibitor trichostatin A (TSA) influenced basal- and androgen-mediated transcriptional activation of the integrated MMTV promoter in the mouse L-cell fibroblast cell line 29+. These cells harbor the MMTV promoter integrated in the genome and express only one steroid hormone receptor subtype, i.e., the AR. Surprisingly, we found that treatment of the cells with TSA alone had virtually no effect on transcription and chromatin remodeling of the MMTV promoter nor on AR levels. However, pretreatment with TSA augmented the DHT effects on all three parameters. These results suggest that histone acetylation changes at the MMTV B nucleosome per se are not alone sufficient to induce chromatin remodeling and subsequent induction of MMTV transcription. Rather, the histone deacetylase inhibitor TSA exerts a portion of its effect on MMTV chromatin remodeling and transcriptional activation indirectly through increases in AR levels.


Subject(s)
Chromatin/genetics , Chromatin/metabolism , Enzyme Inhibitors/pharmacology , Histones/genetics , Histones/metabolism , Hydroxamic Acids/pharmacology , Receptors, Androgen/metabolism , Transcription, Genetic/drug effects , Acetylation , Androgens/pharmacology , Animals , Fibroblasts , Mammary Tumor Virus, Mouse/genetics , Mice , Promoter Regions, Genetic , Transcription, Genetic/genetics
18.
Gastroenterology ; 117(5): 1147-54, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10535878

ABSTRACT

BACKGROUND & AIMS: Transient lower esophageal sphincter relaxation (TLESR) appears to be the most frequent motor event responsible for gastroesophageal reflux. Because TLESRs are considered to be triggered by activation of gastric mechanoreceptors, and because the gamma-aminobutyric acid type B (GABA(B))-receptor agonist baclofen is known to inhibit transmitter release from mechanosensitive afferents, the effects of baclofen on TLESRs in the dog were assessed. METHODS: A total of 183 recordings of the pharyngeal, esophageal, lower esophageal sphincter, and gastric pressures as well as measurement of esophageal pH were performed in 15 awake dogs. Racemic baclofen, its enantiomers, and the GABA(B)-receptor antagonist CGP36742 were administered before stimulation of TLESRs by a liquid meal and air insufflation. The pharmacodynamics of baclofen were compared with its pharmacokinetics. RESULTS: Baclofen dose-dependently inhibited TLESRs, with a 50% effective dose (ED(50)) of 1.0 micromol/kg after intravenous administration. The maximal inhibition amounted to approximately 80%. Intragastric baclofen was almost equally effective (ED(50), 1.8 micromol/kg), compatible with the complete oral availability of the drug (100%). The inhibitory effect of baclofen resided in the pharmacologically active R enantiomer, and CGP36742 reduced some of the effects of baclofen. CONCLUSIONS: Baclofen is a potent and efficacious inhibitor of TLESRs and reflux in the dog. Activation of the GABA(B) receptor may be a new approach to the treatment of reflux disease.


Subject(s)
Esophagogastric Junction/physiology , Muscle Relaxation/physiology , Receptors, GABA-B/physiology , Animals , Baclofen/chemistry , Baclofen/pharmacokinetics , Baclofen/pharmacology , Dogs , Esophagogastric Junction/drug effects , Female , GABA Agonists/chemistry , GABA Agonists/pharmacokinetics , GABA Agonists/pharmacology , GABA Antagonists/pharmacology , GABA-B Receptor Antagonists , Male , Muscle Relaxation/drug effects , Organophosphorus Compounds/pharmacology , Peristalsis/physiology , Pressure , Stereoisomerism , Stomach/drug effects , Stomach/physiology , Time Factors
19.
Gene Ther ; 6(2): 245-52, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10435109

ABSTRACT

Glucocorticoids (GC) are commonly used as anti-inflammatory drugs in asthma, but can produce serious secondary effects and, moreover, be inefficient in corticoresistant asthmatics. After binding to the glucocorticoid receptor (GR), they repress the synthesis of proinflammatory cytokines via inhibition of the transcription factors AP-1 and NF-kappa B. Since qualitative and quantitative defects of the GR have been reported in corticoresistant patients, the transfer of the GR gene in the lung epithelium, the primary site of inflammation in asthma, may restore sensitivity to GC in these patients. As a prerequisite to in vivo studies, we have transfected A549 human lung epithelial cells with a GR expression vector. Using AP-1 and NF-kappa B-dependent reporter gene assays and an immunoassay for the pro-inflammatory cytokine RANTES, we show that the over-expressed GR significantly repressed AP-1 and NF-kappa B activities in the absence of hormone and that the GC dexamethasone produced an additive inhibitory effect. The GC-independent repression of AP-1 and NF-kappa B activities was further demonstrated by overexpressing a ligand-binding deficient GR mutant. Our data suggest that delivery of the GR gene in vivo may reduce inflammation without recourse to GC and may constitute an alternative therapeutic approach for corticoresistant asthma.


Subject(s)
Asthma/therapy , Gene Transfer Techniques , Genetic Therapy/methods , Lung/metabolism , Receptors, Glucocorticoid/genetics , Animals , COS Cells , Chemokine CCL5/metabolism , Dexamethasone/pharmacology , Epithelium/immunology , Epithelium/metabolism , Gene Expression/drug effects , Genes, Reporter , Glucocorticoids/pharmacology , Humans , Luciferases/genetics , Lung/immunology , NF-kappa B/genetics , Transcription Factor AP-1/genetics , Tumor Cells, Cultured , beta-Galactosidase/genetics
20.
Exp Cell Res ; 250(2): 414-22, 1999 Aug 01.
Article in English | MEDLINE | ID: mdl-10413595

ABSTRACT

We examined the interaction between the androgen (AR) and glucocorticoid receptor (GR) at the transcriptional level using mouse fibroblast cell lines harboring an integrated mouse mammary tumor virus (MMTV) promoter. We found that the AR, after induction with dihydrotestosterone (DHT), caused a progressive increase in MMTV-CAT reporter activity over 72 h which was correlated to an increase in chromatin remodeling of the MMTV promoter in the vicinity of the hormone response element (HRE). In contrast, stimulation of the GR by the synthetic glucocorticoid dexamethasone (Dex) caused a transient increase in MMTV transcriptional activity which returned to basal levels after 72 h. These changes were correlated to a transient increase in chromatin remodeling in the region of the HRE. Neither cotreatment nor pretreatment with Dex affected the DHT response. In fact, there was a more than additive effect of the two hormones on transcription at early time points. This suggests that the inability of GR to remodel chromatin, after 24 h of hormone treatment, is most likely related to changes in the GR itself and not the chromatin remodeling process. Consistent with this, nuclear GR levels dropped by greater than 50% after Dex treatment whereas the AR was induced fourfold after 24 h of DHT treatment. We conclude that a promoter with an ordered chromatin structure can still respond to androgens even after its glucocorticoid responsiveness is lost. This may be one mechanism cells utilize to establish target gene specificity for nuclear receptors that recognize identical DNA sequences.


Subject(s)
Chromatin/genetics , Mammary Tumor Virus, Mouse/genetics , Promoter Regions, Genetic/genetics , Receptors, Androgen/metabolism , Receptors, Glucocorticoid/metabolism , Transcriptional Activation/genetics , Animals , Blotting, Western , Cell Nucleus/drug effects , Cell Nucleus/metabolism , Chromatin/chemistry , Chromatin/metabolism , Deoxyribonucleases, Type II Site-Specific/metabolism , Dexamethasone/pharmacology , Dihydrotestosterone/pharmacology , Genes, Reporter , L Cells , Mice , Molecular Structure , Time Factors , Transcriptional Activation/drug effects , Transfection
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