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1.
Phys Rev Lett ; 130(20): 203401, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37267577

ABSTRACT

We determine the phase diagram of strongly correlated fermions in the crossover from Bose-Einstein condensates of molecules (BEC) to Cooper pairs of fermions (BCS) utilizing an artificial neural network. By applying advanced image recognition techniques to the momentum distribution of the fermions, a quantity which has been widely considered as featureless for providing information about the condensed state, we measure the critical temperature and show that it exhibits a maximum on the bosonic side of the crossover. Additionally, we backanalyze the trained neural network and demonstrate that it interprets physically relevant quantities.

2.
Respir Med ; 192: 106726, 2022 02.
Article in English | MEDLINE | ID: mdl-35032737

ABSTRACT

RATIONALE: Recent guidelines consider chronic cough to be a unique clinical entity with different phenotypes. We aimed to investigate them in a general population and to describe prevalence, distribution, and characteristics of these phenotypes within the Austrian general population. METHODS: From the LEAD study, a longitudinal observational population-based cohort, data from questionnaires and spirometry of 10,057 adult participants was analysed. Chronic cough was defined as coughing nearly every day during the last 12 months for at least 3 months (>12 weeks). RESULTS: The prevalence of chronic cough was 9% and increased with age. We found no sex predominance but a female preponderance (68%) in never smokers. A presumable cause was identified in 85% of which more than half (53.9%) had two phenotypes, 36.9% belonged to one only and 9.2% to three or more. Regarding the distribution of phenotypes, 40.8% were current smokers, 32.6% had an ACE inhibitor intake, 18.2% GERD, 17.6% asthmatic cough, 9.7% UACS and 28.3% other diseases associated with chronic cough. 15% had unexplained chronic cough with no identifiable phenotype. Current smoking, low socioeconomic status, obesity, COPD and obstructive sleep apnea were associated factors with chronic cough. CONCLUSION: Chronic cough is common among adults in Austria and highly prevalent in the older population. Most participants can be phenotyped with simple questionnaire-based assessment and can therefore potentially receive specific treatment without intensive clinical workup.


Subject(s)
Cough , Pulmonary Disease, Chronic Obstructive , Austria/epidemiology , Cough/epidemiology , Cough/etiology , Cross-Sectional Studies , Female , Humans , Phenotype , Prevalence , Spirometry
3.
Rev Sci Instrum ; 92(9): 093202, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-34598519

ABSTRACT

Cold atom experiments commonly use broad magnetic Feshbach resonances to manipulate the interaction between atoms. In order to induce quantum dynamics by a change in the interaction strength, rapid (∼µs) magnetic field changes over several tens of Gauss are required. Here, we present a compact design of a coil and its control circuit for a change in the magnetic field up to 36 G in 3 µs. The setup comprises two concentric solenoids with minimal space requirements, which can be readily added to existing apparatuses. This design makes the observation of non-equilibrium physics with broad Feshbach resonances accessible.

4.
Sci Rep ; 7(1): 7899, 2017 08 11.
Article in English | MEDLINE | ID: mdl-28801620

ABSTRACT

Aldosterone antagonists slow the progression of chronic kidney disease (CKD), but their use is limited by hyperkalemia, especially when associated with RAS inhibitors. We examined the renoprotective effects of Ly, a novel non-steroidal mineralocorticoid receptor (MR) blocker, through two experimental protocols: In Protocol 1, male Munich-Wistar rats underwent 5/6 renal ablation (Nx), being divided into: Nx+V, receiving vehicle, Nx+Eple, given eplerenone, 150 mg/kg/day, and Nx+Ly, given Ly, 20 mg/kg/day. A group of untreated sham-operated rats was also studied. Ly markedly raised plasma renin activity (PRA) and aldosterone, and exerted more effective anti-albuminuric and renoprotective action than eplerenone. In Protocol 2, Nx rats remained untreated until Day 60, when they were divided into: Nx+V receiving vehicle; Nx+L treated with losartan, 50 mg/kg/day; Nx+L+Eple, given losartan and eplerenone, and Nx+L+Ly, given losartan and Ly. Treatments lasted for 90 days. As an add-on to losartan, Ly normalized blood pressure and albuminuria, and prevented CKD progression more effectively than eplerenone. This effect was associated with strong stimulation of PRA and aldosterone. Despite exhibiting higher affinity for the MR than either eplerenone or spironolactone, Ly caused no hyperkalemia. Ly may become a novel asset in the effort to detain the progression of CKD.


Subject(s)
Mineralocorticoid Receptor Antagonists/administration & dosage , Renal Insufficiency, Chronic/drug therapy , Albuminuria/prevention & control , Aldosterone/blood , Animals , Blood Pressure , Eplerenone/administration & dosage , Losartan/administration & dosage , Nephrectomy , Rats, Wistar , Renin/blood , Treatment Outcome
5.
Pneumologie ; 69(8): 459-62, 2015 Aug.
Article in German | MEDLINE | ID: mdl-26258419

ABSTRACT

More research is needed to elucidate natural history and underlying pathomechanisms of the most common airway diseases, Asthma and COPD. In the last decade risk factors affecting the natural history of lung function, defined by the decline of lung function over time, have been evaluated. Moreover, scientific methods have been extended and novel biomarkers, genetics, metabolomics, and epidemiology are dominant tools for investigating the natural history of lung function and potential risk factors. Evidence shows that lung function in childhood is a predictor for lung function in adulthood and risk factors starting in utero contribute to lung function decline during life. Therefore, recently it has been hypothesized that COPD begins in childhood. Thus, prospective investigation of lung function changes including novel scientific methodology has been advocated. The Austrian LEAD  study has been initiated in the general population 2012 to investigate the natural history of obstructive airway diseases.


Subject(s)
Aging , Asthma/epidemiology , Asthma/physiopathology , Lung/physiopathology , Pulmonary Disease, Chronic Obstructive/epidemiology , Pulmonary Disease, Chronic Obstructive/physiopathology , Asthma/diagnosis , Austria/epidemiology , Cohort Studies , Disease Progression , Humans , Life Style , Longitudinal Studies , Prevalence , Pulmonary Disease, Chronic Obstructive/diagnosis , Respiratory Function Tests
6.
Int J Clin Pract ; 69(8): 871-82, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26011029

ABSTRACT

AIMS: To examine the rates of diabetic kidney disease (DKD) progression and associated factors, we undertook a study of estimated glomerular filtration rate (eGFR) in a historical cohort of UK primary care patients with type 2 diabetes mellitus (T2DM) and associated DKD from the Clinical Practice Research Datalink. METHODS: Our eligible population were patients with definitive T2DM from a recorded diagnostic code with either a diagnosis of chronic kidney disease (CKD) or renal function test values and renal abnormalities consistent with a CKD diagnosis, identified between 1 October 2006 and 31 December 2011. Only patients with albuminuria results reported in mg/l were used for the longitudinal statistical analyses of the eGFR rate of change using multilevel models. RESULTS: We identified 111,030 patients with T2DM. Among them 58.6% (95% confidence interval (CI): 58.3-58.9) had CKD and 37.2% (95% CI: 36.9-37.5%) had presumed DKD at baseline. Only 19.4% of patients had urinary albumin test results expressed as mg/l in the year prior to index date. Almost two-thirds (63.8%) of patients with T2DM and presumed DKD received prescriptions for angiotensin-converting enzyme (ACE) inhibitors or angiotensin type 1 receptor blockers (ARB) or both. Time-dependent variables that predict subsequent eGFR decline include increased albuminuria, time from index date and older age. CONCLUSION: Only a minority of diabetic patients with DKD had quantitative albuminuria assessments. The relatively low proportion of DKD patients with ACEi or ARB prescriptions suggests a gap between healthcare practice and available scientific evidence during the study period. Increased albuminuria and older age were the most consistent predictors of subsequent eGFR decline.


Subject(s)
Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/physiopathology , Glomerular Filtration Rate/physiology , Kidney Failure, Chronic/physiopathology , Age Factors , Aged , Albuminuria/diagnosis , Angiotensin II Type 1 Receptor Blockers/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/epidemiology , Disease Progression , Female , Humans , Kidney Failure, Chronic/drug therapy , Kidney Failure, Chronic/epidemiology , Male , Middle Aged , Prevalence , Primary Health Care/statistics & numerical data , Retrospective Studies , United Kingdom/epidemiology
7.
Eur Respir J ; 35(1): 88-94, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19541716

ABSTRACT

Weaning from mechanical ventilation was categorised as simple, difficult or prolonged by an international task force of the American Thoracic Society/European Respiratory Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine/Sociéte de Réanimation de Langue Française in 2007. This new classification has not been tested in clinical practice. The objective of the present study was to determine the incidence and outcome of weaning according to the new categories. We included medical and surgical patients who required mechanical ventilation in a prospective, multicentre, 6-month cohort study. From an initial cohort of 510 patients, 257 intubated patients started weaning. Of these patients, the cumulative incidences of simple, difficult, and prolonged weaning were 152 (59%), 68 (26%) and 37 (14%), respectively. Hospital mortality was increased in patients with prolonged (32%) but not difficult (9%) weaning in comparison with those with simple weaning (13%), overall p = 0.0205. In a multivariate logistic regression model, prolonged but not difficult weaning was associated with an increased risk of death. Ventilator-free days and intensive care unit (ICU)-free days were decreased in both difficult and prolonged weaning. In conclusion, the new weaning category prolonged weaning is associated with increased mortality and morbidity in the ICU. The new category difficult to wean was associated with increased morbidity, but not mortality.


Subject(s)
Ventilator Weaning/classification , Female , Humans , Incidence , Male , Middle Aged , Prospective Studies , Time Factors , Treatment Outcome , Ventilator Weaning/adverse effects , Ventilator Weaning/mortality
8.
Respiration ; 78(2): 161-7, 2009.
Article in English | MEDLINE | ID: mdl-19174602

ABSTRACT

BACKGROUND: The prevalence of asthma and chronic obstructive pulmonary disease (COPD) is high ( approximately 7.4-18%) in the general population, but less than half are diagnosed. Several studies have shown FEV(6) as a good surrogate marker for forced vital capacity (FVC) to detect airflow limitations. OBJECTIVES: The aim of this study was to evaluate if it is possible to simplify and improve the diagnosis of so far undiagnosed asthma or COPD in the primary care setting by measuring FEV(6) with a new simple screening device (PiKo-6). METHODS: 507 patients were recruited from three general practices from May to June 2005. Patients with any known pulmonary disease were excluded by questionnaire. FEV(1), FEV(6) and FEV(1)/FEV(6) were determined using a PiKo-6 device. Patients with an FEV(1)/FEV(6) <80% (PiKo positive) were invited to a standardized pulmonary function test to confirm or rule out airflow limitation. RESULTS: 401 (79.1%) patients showed FEV(1)/FEV(6) > or =80% (PiKo negative), and 106 (20.9%) patients were PiKo positive. Of the 106 PiKo-positive patients, 74 patients (14.7% of total) agreed to further studies and 18 patients (3.6%) of them suffered from COPD [COPD 0: 5 (1.0%); COPD I: 9 (1.8%); COPD II: 4 (0.8%), and none with COPD III or IV] and 14 patients (2.8%) suffered from bronchial hyperresponsiveness or asthma. In 42 patients (8.3%), the pulmonary function test was normal. CONCLUSIONS: Measurement of FEV(6) using a new simple screening device (PiKo-6) may improve the detection rate of undiagnosed airflow limitation in the primary care setting. However, patients should be carefully selected.


Subject(s)
Airway Obstruction/diagnosis , Forced Expiratory Volume , Mass Screening/instrumentation , Primary Health Care , Adult , Aged , Female , Humans , Male , Middle Aged , Surveys and Questionnaires
9.
Kidney Int ; 71(11): 1105-15, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17361113

ABSTRACT

Small lipids such as eicosanoids exert diverse and complex functions. In addition to their role in regulating normal kidney function, these lipids also play important roles in the pathogenesis of kidney diseases. Cyclooxygenase (COX)-derived prostanoids play important role in maintaining renal function, body fluid homeostasis, and blood pressure. Renal cortical COX2-derived prostanoids, particularly (PGI2) and PGE2 play critical roles in maintaining blood pressure and renal function in volume contracted states. Renal medullary COX2-derived prostanoids appear to have antihypertensive effect in individuals challenged with a high salt diet. 5-Lipoxygenase (LO)-derived leukotrienes are involved in inflammatory glomerular injury. LO product 12-hydroxyeicosatetraenoic acid (12-HETE) is associated with pathogenesis of hypertension, and may mediate angiotensin II and TGFbeta induced mesengial cell abnormality in diabetic nephropathy. P450 hydroxylase-derived 20-HETE is a potent vasoconstrictor and is involved in the pathogenesis of hypertension. P450 epoxygenase derived epoxyeicosatrienoic acids (EETs) have vasodilator and natriuretic effect. Blockade of EET formation is associated with salt-sensitive hypertension. Ceramide has also been demonstrated to be an important signaling molecule, which is involved in pathogenesis of acute kidney injury caused by ischemia/reperfusion, and toxic insults. Those pathways should provide fruitful targets for intervention in the pharmacologic treatment of renal disease.


Subject(s)
Arachidonic Acids/metabolism , Kidney/metabolism , Animals , Arachidonic Acids/chemistry , Blood Pressure , Ceramides/metabolism , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/metabolism , Cytochrome P-450 Enzyme System/metabolism , Humans , Hypertension/metabolism , Kidney/enzymology , Kidney/physiology , Kidney/physiopathology , Models, Biological
10.
Diabetologia ; 50(2): 452-60, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17151860

ABSTRACT

AIMS/HYPOTHESIS: In the current study, the effect of a highly specific peptide inhibitor of glycogen synthase kinase 3 (GSK3) (L803-mts) on glucose metabolism and BP was examined in a high-fat (HF) fed mouse model of diabetes. METHODS: C57/BL6J mice were placed on an HF diet for 3 months and treated with L803-mts for 20 days, following which glucose metabolism was examined by euglycaemic-hyperinsulinaemic clamp studies. BP and heart rate were measured by radio-telemetry. RESULTS: The HF mice were obese, with impaired glucose tolerance and high plasma insulin and leptin levels. L803-mts treatment significantly reduced the insulin levels and doubled the glucose infusion rate required to maintain a euglycaemic condition in the HF+L803-mts group compared with the HF group. Insulin failed to suppress the endogenous glucose production rate in the HF group while decreasing it by 75% in the HF+L803-mts group, accompanied by increased liver glycogen synthase activity and net hepatic glycogen synthesis. GSK3 inhibition also reduced peripheral insulin resistance. Plasma glucose disappearance rate increased by 60% in the HF+L803-mts group compared with the HF group. In addition, glucose uptake in heart and gastrocnemius muscle was markedly improved. Although mean arterial pressure increased following the HF diet, it did not change significantly during the 12 days of L803-mts treatment. CONCLUSIONS/INTERPRETATION: These studies demonstrate that GSK3 inhibition improved hepatic and peripheral insulin resistance in a mouse model of HF-induced diabetes, but it failed to have an effect on BP. GSK3 may represent an important therapeutic target for insulin resistance.


Subject(s)
Blood Glucose/metabolism , Dietary Fats , Glycogen Synthase Kinase 3/antagonists & inhibitors , Hypertension/physiopathology , Insulin/pharmacology , Animals , Blood Glucose/drug effects , Glucagon/blood , Glycogen Synthase Kinase 3/metabolism , Male , Mice , Mice, Inbred C57BL , Muscle, Skeletal/enzymology , Oligopeptides/pharmacology
11.
Kidney Int ; 70(3): 460-70, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16775606

ABSTRACT

Excessive glomerular collagen IV and reactive oxygen species (ROS) production are key factors in the development of diabetic nephropathy. Integrin alpha1beta1, the major collagen IV receptor, dowregulates collagen IV and ROS production, suggesting this integrin might determine the severity of diabetic nephropathy. To test this possibility, wild-type and integrin alpha1-null mice were rendered diabetic with streptozotocin (STZ) (100 mg/kg single intraperitoneal injection), after which glomerular filtration rate (GFR), glomerular collagen deposition, and glomerular basement membrane (GBM) thickening were evaluated. In addition, ROS and collagen IV production by mesangial cells as well as their proliferation was measured in vitro. Diabetic alpha1-null mice developed worse renal disease than diabetic wild-type mice. A significant increase in GFR was evident in the alpha1-null mice at 6 weeks after the STZ injection; it started to decrease by week 24 and reached levels of non-diabetic mice by week 36. In contrast, GFR only increased in wild-type mice at week 12 and its elevation persisted throughout the study. Diabetic mutant mice also showed increased glomerular deposition of collagen IV and GBM thickening compared to diabetic wild-type mice. Primary alpha1-null mesangial cells exposed to high glucose produced more ROS than wild-type cells, which led to decreased proliferation and increased collagen IV synthesis, thus mimicking the in vivo finding. In conclusion, this study suggests that lack of integrin alpha1beta1 exacerbates the glomerular injury in a mouse model of diabetes by modulating GFR, ROS production, cell proliferation, and collagen deposition.


Subject(s)
Diabetic Nephropathies/metabolism , Diabetic Nephropathies/pathology , Integrin alpha1/genetics , Integrin alpha1beta1/metabolism , Mesangial Cells/metabolism , Mesangial Cells/pathology , Animals , Basement Membrane/metabolism , Basement Membrane/pathology , Cell Division , Cell Movement , Cells, Cultured , Collagen Type IV/metabolism , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Disease Models, Animal , Glomerular Filtration Rate , Glucose/pharmacology , Glycation End Products, Advanced/metabolism , Integrin alpha1/metabolism , Male , Mesangial Cells/drug effects , Mice , Mice, Inbred BALB C , Mice, Knockout , Oxidative Stress/drug effects , Oxidative Stress/physiology , Reactive Oxygen Species/metabolism
12.
Kidney Int ; 69(9): 1511-7, 2006 May.
Article in English | MEDLINE | ID: mdl-16672921

ABSTRACT

Peroxisome proliferator-activated receptor alpha (PPARalpha) is a member of the ligand-activated nuclear receptor superfamily, and plays an important role in lipid metabolism and glucose homeostasis. The purpose of this study is to determine whether the activation of PPARalpha by fenofbrate would improve diabetes and its renal complications in type II diabetes mellitus. Male C57 BLKS db/db mice and db/m controls at 8 weeks of age were divided to receive either a regular diet chow (db/db, n=8; db/m, n=6) or a diet containing fenofibrate (db/db, n=8; db/m, n=7). Mice were followed for 8 weeks. Fenofibrate treatment dramatically reduced fasting blood glucose (P<0.001) and HbA1c levels (P<0.001), and was associated with decreased food intake (P<0.01) and slightly reduced body weight. Fenofibrate also ameliorated insulin resistance (P<0.001) and reduced plasma insulin levels (P<0.05) in db/db mice. Hypertrophy of pancreatic islets was decreased and insulin content markedly increased (P<0.05) in fenofibrate-treated diabetic animals. In addition, fenofibrate treatment significantly reduced urinary albumin excretion (P<0.001). This was accompanied by dramatically reduced glomerular hypertrophy and mesangial matrix expansion. Furthermore, the addition of fenofibrate to cultured mesangial cells, which possess functional active PPARalpha, decreased type I collagen production. Taken together, the PPARalpha agonist fenofibrate dramatically improves hyperglycemia, insulin resistance, albuminuria, and glomerular lesions in db/db mice. The activation of PPARalpha by fenofibrate in mesangial cells may partially contribute to its renal protection. Thus, fenofibrate may serve as a therapeutic agent for type II diabetes and diabetic nephropathy.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Diabetic Nephropathies/drug therapy , Fenofibrate/therapeutic use , Hypolipidemic Agents/therapeutic use , PPAR alpha/agonists , Albuminuria/drug therapy , Animals , Blood Glucose/analysis , Body Weight/drug effects , Cells, Cultured , Collagen Type I/antagonists & inhibitors , Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/pathology , Fenofibrate/pharmacology , Glycated Hemoglobin/analysis , Hyperglycemia/drug therapy , Hypolipidemic Agents/pharmacology , Insulin/blood , Insulin Resistance , Islets of Langerhans/drug effects , Islets of Langerhans/pathology , Kidney Glomerulus/chemistry , Kidney Glomerulus/drug effects , Kidney Glomerulus/pathology , Male , Mesangial Cells/chemistry , Mesangial Cells/drug effects , Mesangial Cells/pathology , Mice , Mice, Mutant Strains , PPAR alpha/analysis , PPAR alpha/metabolism , Treatment Outcome
14.
Am J Physiol Renal Physiol ; 281(6): F1036-46, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11704554

ABSTRACT

Peroxisome proliferator-activated receptor-gamma (PPAR gamma) is a nuclear transcription factor and the pharmacological target for antidiabetic thiazolidinediones (TZDs). TZDs ameliorate diabetic nephropathy and have direct effects on cultured mesangial cells (MCs); however, in situ hybridization failed to detect expression of PPAR gamma in glomeruli in vivo. The purpose of this study was to determine whether PPAR gamma is expressed in renal glomeruli. Two rabbit PPAR gamma isoforms were cloned. Nuclease protection assays demonstrate that both PPAR gamma isoforms are expressed in freshly isolated glomeruli. Treatment of rabbits with the TZD troglitazone selectively induced expression of an endogenous PPAR gamma target gene, adipocyte fatty acid-binding protein (A-FABP), in renal glomerular cells and renal medullary microvascular endothelial cells, demonstrated by both in situ hybridization and immunostain. Troglitazone also dramatically increased A-FABP expression in cultured MCs. Constitutive PPAR gamma expression was detected in cultured rabbit MCs. Endogenous MC PPAR gamma can also drive PPAR gamma reporter. Troglitazone and 15-deoxy-Delta 12,14 prostaglandin J(2) at low concentrations reduced mesangial cell [(3)H]thymidine incorporation without affecting viability. These data suggest that constitutive PPAR gamma activity exists in renal glomeruli in vivo and could provide a pharmacological target to directly modulate glomerular injury.


Subject(s)
Kidney Glomerulus/blood supply , Kidney Glomerulus/metabolism , Neoplasm Proteins , Prostaglandin D2/analogs & derivatives , Receptors, Cytoplasmic and Nuclear/metabolism , Thiazolidinediones , Transcription Factors/metabolism , Amino Acid Sequence , Animals , Base Sequence , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Division/drug effects , Cell Survival/drug effects , Cells, Cultured , Chromans/pharmacology , Cloning, Molecular , Endothelium, Vascular/metabolism , Fatty Acid-Binding Proteins , Glomerular Mesangium/drug effects , Glomerular Mesangium/metabolism , Hypoglycemic Agents/pharmacology , Kidney Glomerulus/drug effects , Molecular Sequence Data , Prostaglandin D2/pharmacology , RNA, Messenger/biosynthesis , Rabbits , Receptors, Cytoplasmic and Nuclear/agonists , Receptors, Cytoplasmic and Nuclear/genetics , Thiazoles/pharmacology , Transcription Factors/agonists , Transcription Factors/genetics , Transcriptional Activation , Troglitazone
15.
Am J Physiol Renal Physiol ; 281(6): F1173-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11704570

ABSTRACT

PGE(2) plays a critical role in regulating renal function and facilitating reproduction. One of the rate-limiting biosynthetic enzymes in PGE(2) synthesis is the terminal PGE(2) synthase (PGES). In the present studies, we report the functional expression of a membrane-associated murine PGES (mPGES) and its expression in urogenital tissues. Two independent cDNA clones sharing an identical open reading frame of 459 bp and encoding a peptide of 153 amino acids, but differing in the 3'-untranslated region, were identified. Assays for enzymatic activity, using microsomes prepared from cells transfected with mPGES cDNA, showed that these cDNA sequences encode a functional protein that catalyzes the conversion of PGH(2) to PGE(2). Constitutive expression of mPGES was highest in the mouse kidney, ovary, and urinary bladder but was also expressed at lower levels in uterus and testis. Renal mPGES expression was predominantly localized to epithelia of distal tubules and medullary collecting ducts. High expression was also seen in transitional epithelial cells of bladder and ureter and in the primary and secondary follicles in the ovary. In conclusion, mPGES is constitutively expressed along the urogenital tract, where it may have important roles in normal physiology and disease.


Subject(s)
Intramolecular Oxidoreductases/metabolism , Urogenital System/enzymology , Amino Acid Sequence , Animals , Base Sequence , COS Cells , Cloning, Molecular , Immunohistochemistry , In Situ Hybridization , Intracellular Membranes/enzymology , Intramolecular Oxidoreductases/genetics , Intramolecular Oxidoreductases/immunology , Kidney Tubules/enzymology , Kinetics , Mice , Microsomes/enzymology , Molecular Sequence Data , Prostaglandin-E Synthases , RNA, Messenger/biosynthesis , Transfection
16.
Neoplasia ; 3(4): 287-303, 2001.
Article in English | MEDLINE | ID: mdl-11571629

ABSTRACT

Recent studies in prostate tissues and especially cell lines have suggested roles for arachidonic acid (AA) metabolizing enzymes in prostate adenocarcinoma (Pca) development or progression. The goal of this study was to more fully characterize lipoxygenase (LOX) and cyclooxygenase-2 (COX-2) gene expression and AA metabolism in benign and malignant prostate using snap-frozen tissues obtained intraoperatively and mRNA analyses and enzyme assays. Formation of 15-hydroxyeicosatetraenoic acid (15-HETE) was detected in 23/29 benign samples and 15-LOX-2 mRNA was detected in 21/25 benign samples. In pairs of pure benign and Pca from the same patients, 15-HETE production and 15-LOX-2 mRNA were reduced in Pca versus benign in 9/14 (P=.04) and 14/17 (P=.002), respectively. Under the same conditions, neither 5-HETE nor 12-HETE formation was detectable in 29 benign and 24 tumor samples; with a more sensitive assay, traces were detected in some samples, but there was no clear association with tumor tissue. COX-2 mRNA was detected by nuclease protection assay in 7/16 benign samples and 5/16 tumors. In benign and tumor pairs from 10 patients, COX-2 was higher in tumor versus benign in only 2, with similar results by in situ hybridization. Paraffin immunoperoxidase for COX-2 was performed in whole mount sections from 87 additional radical prostatectomy specimens, with strong expression in ejaculatory duct as a positive control and corroboration with in situ hybridization. No immunostaining was detected in benign prostate or tumor in 45% of cases. Greater immunostaining in tumor versus benign was present in only 17% of cases, and correlated with high tumor grade (Gleason score 8 and 9 vs. 5 to 7). In conclusion, reduced 15-LOX-2 expression and 15-HETE formation is the most characteristic alteration of AA metabolism in Pca. Increased 12-HETE and 5-HETE formation in Pca were not discernible. Increased COX-2 expression is not a typical abnormality in Pca in general, but occurs in high-grade tumors.


Subject(s)
Adenocarcinoma/enzymology , Isoenzymes/genetics , Lipoxygenase/genetics , Prostaglandin-Endoperoxide Synthases/genetics , Prostatic Neoplasms/enzymology , RNA, Messenger/metabolism , RNA, Neoplasm/metabolism , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Arachidonic Acid/metabolism , Blotting, Northern , Chromatography, High Pressure Liquid , Cyclooxygenase 2 , Dinoprostone/metabolism , Humans , Hydroxyeicosatetraenoic Acids/metabolism , Immunoenzyme Techniques , In Situ Hybridization , Isoenzymes/metabolism , Lipoxygenase/metabolism , Male , Membrane Proteins , Paraffin Embedding , Prostaglandin-Endoperoxide Synthases/metabolism , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology
17.
Am J Physiol Renal Physiol ; 281(1): F1-11, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11399641

ABSTRACT

In adult mammalian kidney, cyclooxygenase-2 (COX-2) expression is found in a restricted subpopulation of cells. The two sites of renal COX-2 localization detected in all species to date are the macula densa (MD) and associated cortical thick ascending limb (cTALH) and medullary interstitial cells (MICs). Physiological regulation of COX-2 in these cellular compartments suggests functional roles for eicosanoid products of the enzyme. COX-2 expression increases in high-renin states (salt restriction, angiotensin-converting enzyme inhibition, renovascular hypertension), and selective COX-2 inhibitors significantly decrease plasma renin levels, renal renin activity, and mRNA expression. There is evidence for negative regulation of MD/cTALH COX-2 by angiotensin II and by glucocorticoids and mineralocorticoids. Conversely, nitric oxide generated by neuronal nitric oxide synthase is a positive modulator of COX-2 expression. Decreased extracellular chloride increases COX-2 expression in cultured cTALH, an effect mediated by increased p38 mitogen-activated protein kinase activity, and, in vivo, a sodium-deficient diet increases expression of activated p38 in MD/cTALH. In contrast to COX-2 in MD/cTALH, COX-2 expression increases in MICs in response to a high-salt diet as well as water deprivation. Studies in cultured MICs have confirmed that expression is increased in response to hypertonicity and is mediated, at least in part, by nuclear factor-kappaB activation. COX-2 inhibition leads to apoptosis of MICs in response to hypertonicity in vitro and after water deprivation in vivo. In addition, COX-2 metabolites appear to be important mediators of medullary blood flow and renal salt handling. Therefore, there is increasing evidence that COX-2 is an important physiological mediator of kidney function.


Subject(s)
Gene Expression Regulation, Enzymologic , Isoenzymes/metabolism , Kidney/physiology , Prostaglandin-Endoperoxide Synthases/metabolism , Animals , Cyclooxygenase 2 , Humans , Isoenzymes/genetics , Kidney/enzymology , Kidney Cortex/enzymology , Kidney Medulla/enzymology , Membrane Proteins , Prostaglandin-Endoperoxide Synthases/genetics , Transcription, Genetic
18.
Kidney Int ; 60(1): 14-30, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11422732

ABSTRACT

Peroxisome proliferator-activated receptors (PPARs): Novel therapeutic targets in renal disease. Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand-dependent transcription factors. PPARs play an important role in the general transcriptional control of numerous cellular processes, including lipid metabolism, glucose homeostasis, cell cycle progression, cell differentiation, inflammation and extracellular matrix remodeling. Three PPAR isoforms, designated PPARalpha, PPARbeta and PPARgamma, have been cloned and are differentially expressed in several tissues including the kidney. PPARalpha primary regulates lipid metabolism and modulates inflammation. PPARalpha is the molecular target of the hypolipidemic fibrates including bezafibrate and clofibrate. PPARbeta participates in embryonic development, implantation and bone formation. PPARgamma is a key factor in adipogenesis and also plays an important role in insulin sensitivity, cell cycle regulation and cell differentiation. Antidiabetic thiazolidinediones (TZDs) such as troglitazone and rosiglitazone are specific ligands of PPARgamma, and this interaction is responsible for the insulin-sensitizing and hypoglycemic effect of these drugs. The kidney has been shown to differentially express all PPAR isoforms. PPARalpha is predominantly expressed in proximal tubules and medullary thick ascending limbs, while PPARgamma is expressed in medullary collecting ducts, pelvic urothelium and glomerular mesangial cells. PPARbeta is ubiquitously expressed at low levels in all segments of nephron. Accumulating data has begun to emerge suggesting physiological and pathophysiological roles of PPARs in several tissues including the kidney. The availability of PPAR-selective agonists and antagonists may provide a new approach to modulate the renal response to diseases including glomerulonephritis, glomerulosclerosis and diabetic nephropathy.


Subject(s)
Kidney Diseases/drug therapy , Receptors, Cytoplasmic and Nuclear/therapeutic use , Transcription Factors/therapeutic use , Animals , Cloning, Molecular , Humans , Kidney/metabolism , Ligands , Protein Isoforms/physiology , Receptors, Cytoplasmic and Nuclear/genetics , Receptors, Cytoplasmic and Nuclear/physiology , Tissue Distribution , Transcription Factors/genetics , Transcription Factors/physiology
19.
J Biol Chem ; 276(27): 25467-79, 2001 Jul 06.
Article in English | MEDLINE | ID: mdl-11328810

ABSTRACT

A cDNA encoding a new cytochrome P450 was isolated from a mouse brain library. Sequence analysis reveals that this 1,958-base pair cDNA encodes a 57-58-kDa 502-amino acid polypeptide that is 70-91% identical to CYP2J subfamily P450s and is designated CYP2J9. Recombinant CYP2J9 was co-expressed with NADPH-cytochrome P450 oxidoreductase (CYPOR) in Sf9 cells using a baculovirus system. Microsomes of CYP2J9/CYPOR-transfected cells metabolize arachidonic acid to 19-hydroxyeicosatetraenoic acid (HETE) thus CYP2J9 is enzymologically distinct from other P450s. Northern analysis reveals that CYP2J9 transcripts are present at high levels in mouse brain. Mouse brain microsomes biosynthesize 19-HETE. RNA polymerase chain reaction analysis demonstrates that CYP2J9 mRNAs are widely distributed in brain and most abundant in the cerebellum. Immunoblotting using an antibody raised against human CYP2J2 that cross-reacts with CYP2J9 detects a 56-kDa protein band that is expressed in cerebellum and other brain segments and is regulated during postnatal development. In situ hybridization of mouse brain sections with a CYP2J9-specific riboprobe and immunohistochemical staining with the anti-human CYP2J2 IgG reveals abundant CYP2J9 mRNA and protein in cerebellar Purkinje cells. Importantly, 19-HETE inhibits the activity of recombinant P/Q-type Ca(2+) channels that are known to be expressed preferentially in cerebellar Purkinje cells and are involved in triggering neurotransmitter release. Based on these data, we conclude that CYP2J9 is a developmentally regulated P450 that is abundant in brain, localized to cerebellar Purkinje cells, and active in the biosynthesis of 19-HETE, an eicosanoid that inhibits activity of P/Q-type Ca(2+) channels. We postulate that CYP2J9 arachidonic acid products play important functional roles in the brain.


Subject(s)
Brain/enzymology , Mixed Function Oxygenases/genetics , Amino Acid Sequence , Animals , Arachidonic Acid/metabolism , Baculoviridae , Base Sequence , Calcium Channels/metabolism , Cell Line , DNA, Complementary/chemistry , DNA, Complementary/isolation & purification , Hydroxyeicosatetraenoic Acids/metabolism , In Situ Hybridization , Mice , Microsomes/enzymology , Mixed Function Oxygenases/isolation & purification , Mixed Function Oxygenases/metabolism , Molecular Sequence Data , Molecular Weight , Purkinje Cells/metabolism , RNA, Messenger/metabolism , Sequence Analysis, DNA , Spodoptera , Transfection
20.
Proc Natl Acad Sci U S A ; 98(9): 5211-6, 2001 Apr 24.
Article in English | MEDLINE | ID: mdl-11320253

ABSTRACT

Hypertension is a leading cause of cardiovascular, cerebral, and renal disease morbidity and mortality. Here we show that disruption of the Cyp 4a14 gene causes hypertension, which is, like most human hypertension, more severe in males. Male Cyp 4a14 (-/-) mice show increases in plasma androgens, kidney Cyp 4a12 expression, and the formation of prohypertensive 20-hydroxyarachidonate. Castration normalizes the blood pressure of Cyp 4a14 (-/-) mice and minimizes Cyp 4a12 expression and arachidonate omega-hydroxylation. Androgen replacement restores hypertensive phenotype, Cyp 4a12 expression, and 20-hydroxy-arachidonate formation. We conclude that the androgen-mediated regulation of Cyp 4a arachidonate monooxygenases is an important component of the renal mechanisms that control systemic blood pressures. These results provide direct evidence for a role of Cyp 4a isoforms in cardiovascular physiology, establish Cyp 4a14 (-/-) mice as a monogenic model for the study of cause/effect relationships between blood pressure, sex hormones, and P450 omega-hydroxylases, and suggest the human CYP 4A homologues as candidate genes for the analysis of the genetic and molecular basis of human hypertension.


Subject(s)
Androgens/pharmacology , Cytochrome P-450 Enzyme System/metabolism , Hypertension/enzymology , Mixed Function Oxygenases/metabolism , Androgens/blood , Animals , Arachidonic Acid/metabolism , Blood Pressure , Castration , Cytochrome P-450 CYP4A , Cytochrome P-450 Enzyme System/genetics , Dihydrotestosterone/pharmacology , Enzyme Induction/drug effects , Female , Gene Deletion , Hydroxyeicosatetraenoic Acids/metabolism , Hypertension/chemically induced , Hypertension/genetics , Kidney/blood supply , Kidney/drug effects , Kidney/enzymology , Kidney/metabolism , Male , Mice , Mice, Knockout , Microsomes/drug effects , Microsomes/enzymology , Mixed Function Oxygenases/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Renal Circulation/physiology , Sex Characteristics , Testosterone/pharmacology , Vascular Resistance
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