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1.
Health Econ ; 30(12): 3186-3202, 2021 12.
Article in English | MEDLINE | ID: mdl-34585467

ABSTRACT

This paper is one of the first to investigate mobility in overall health using high-quality administrative data. The attractiveness of this approach lies in objective health measures and large sample sizes allowing twin analyses. I operationalize health mobility by a variety of statistics: rank-rank slopes, intergenerational correlations (IGCs) and sibling and identical twin correlations. I find rank-rank slopes and IGCs in the range 0.11-0.15 and sibling correlations in the range 0.14-0.20. Mobility in health is thus relatively high, both when compared to similar US-based studies, and when contrasted with outcomes such as educational attainment and income. Comparing sibling and identical twin correlations with parent-child associations confirms earlier findings in the literature on equality of opportunity, namely that sibling correlations capture far more variation than traditional IGCs. I conclude that 14%-38% of the variation in individual health outcomes can be attributed to family background and genes, factors which the individual cannot be held accountable for. This finding suggests that simple parent-child associations may be a poor metric for measuring health mobility.


Subject(s)
Income , Social Mobility , Denmark , Educational Status , Humans , Intergenerational Relations , Socioeconomic Factors
2.
Article in English | MEDLINE | ID: mdl-32730916

ABSTRACT

It is thought that the hippocampal neurogenesis is an important mediator of the antidepressant effect of electroconvulsive therapy (ECT). However, most previous studies failed to demonstrate the relationship between the increase in the hippocampal volume and the antidepressant effect. We reinvestigated this relationship by looking at distinct hippocampal subregions and applying repeated measures correlation. Using a 3 Tesla MRI-scanner, we scanned 22 severely depressed in-patients at three time points: before the ECT series, after the series, and at six-month follow-up. The depression severity was assessed by the 17-item Hamilton Rating Scale for Depression (HAMD-17). The hippocampus was segmented into subregions using Freesurfer software. The dentate gyrus (DG) was the primary region of interest (ROI), due to the role of this region in neurogenesis. The other major hippocampal subregions were the secondary ROIs (n = 20). The general linear mixed model and the repeated measures correlation were used for statistical analyses. Immediately after the ECT series, a significant volume increase was present in the right DG (Cohen's d = 1.7) and the left DG (Cohen's d = 1.5), as well as 15 out of 20 secondary ROIs. The clinical improvement, i.e., the decrease in HAMD-17 score, was correlated to the increase in the right DG volume (rrm = -0.77, df = 20, p < .001), and the left DG volume (rrm = -0.75, df = 20, p < .001). Similar correlations were observed in 14 out of 20 secondary ROIs. Thus, ECT induces an increase not only in the volume of the DG, but also in the volume of other major hippocampal subregions. The volumetric increases may reflect a neurobiological process that may be related to the ECT's antidepressant effect. Further investigation of the relationship between hippocampal subregions and the antidepressant effect is warranted. A statistical approach taking the repeated measurements into account should be preferred in the analyses.


Subject(s)
Depressive Disorder, Major/diagnostic imaging , Electroconvulsive Therapy , Hippocampus/diagnostic imaging , Adult , Depressive Disorder, Major/therapy , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Organ Size , Treatment Outcome
3.
Clin Epidemiol ; 12: 95-103, 2020.
Article in English | MEDLINE | ID: mdl-32158272

ABSTRACT

AIM: The prevalence and mortality of abdominal aortic aneurysms (AAA) has been reported to decline. The aim of this study is to compare survival, prevalence, and repair rate of AAA in Denmark in the 1990s, the 2000s and the 2010s - and to examine any change in factors known to influence the prevalence. METHODS: Baseline status and up to 5-year outcomes of 34,079 general population men aged 65-74 were obtained from three RCTs; the Viborg study (1994-1998, n=4,860), the Viborg Vascular (VIVA) trial (2008-2011, n=18,748), and the Danish Cardiovascular (DANCAVAS) trial (2015-2018, n=10,471). After the millennium (VIVA and DANCAVAS) men with AAA were further offered low dose aspirin and statins. Follow-up data were not available for the DANCAVAS trial yet. RESULTS: Across the three decades, the AAA prevalence was 3.8% (Reference), 3.3% (p<0.001) and 4.2% (p=0.882), the proportion of smokers were 62%, 42% and 34% (p<0.001) amongst men with AAA, but AAA risk associations with smoking increased during the decades suggesting increased tobacco consumption of smokers. In addition, the proportions of attenders with ischemic heart disease or stroke increased significantly. The aneurysmal progression rate in the 1990s was 2.90 vs 2.98 mm/year in the 2000s (p=0.91). The need for preventive AAA repair increased insignificantly in the 2000s (Age adj. HR= 1.29, 95% C.I.: 0.95; 1.71, p=0.10), and mortality of men with screen-detected AAA was lower in the 2000s compared to the 1990s (Age-adj. HR= 0.28, 95% C.I.: 0.22; 0.36, p<0.001). CONCLUSION: The Danish prevalence of AAA today compares to the nineties. Unchanged aneurysmal progression rates combined with improved survival of men at risk of AAA leave them in longer time to develop an AAA, be diagnosed and to need later aneurysmal repair or experience rupture. CLINICAL TRIAL REGISTRATIONS: Viborg study: No possibility of registration in the nineties. VIVA: NCT00662480, URL: https://clinicaltrials.gov/show/NCT00662480, DANCAVAS: ISRCTN12157806, URL: http://www.isrctn.com/ISRCTN12157806.

4.
J Vasc Surg ; 71(6): 1921-1929, 2020 06.
Article in English | MEDLINE | ID: mdl-31784280

ABSTRACT

OBJECTIVE: Identifying biomarkers for abdominal aortic aneurysms (AAA) could prove beneficial in prognosis of AAA and thus the selection for treatment. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein that is highly expressed in aorta. MFAP4 is involved in several tissue remodeling-related diseases. We aimed to investigate the potential role of plasma MFAP4 (pMFAP4) as a biomarker of AAA. METHODS: Plasma samples and data were obtained for 504 male AAA patients and 188 controls in the Viborg Vascular (VIVA) screening trial. The pMFAP4 levels were measured by Alphalisa. The Mann-Whitney U test assessed differences in pMFAP4 levels between the presence and absence of different exposures of interest. The correlation between pMFAP4 and aorta growth rate were investigated through spearman's correlation analysis. Immunohistochemistry and multiple logistic regression adjusted for potential confounders assessed the association between pMFAP4 and AAA. Multiple linear regression assessed the correlation between pMFAP4 and aorta growth rate. Cox regression and competing risk regression were used to investigate the correlation between AAA patients with upper tertile pMFAP4 and the risk of undergoing later surgical repair. RESULTS: A significant negative correlation between pMFAP4 and aorta growth rate was observed using spearman's correlation analysis (ρ = -0.14; P = .0074). However, this finding did not reach significance when applying multiple linear regression. A tendency of decreased pMFAP4 was observed in AAA using immunohistochemistry. Competing risk regression adjusted for potential confounders indicated that patients with upper tertile pMFAP4 had a hazard ratio of 0.51 (P = .001) for risk of undergoing later surgical repair. CONCLUSIONS: High levels of pMFAP4 are associated with a decreased likelihood of receiving surgical repair in AAA. This observation warrants confirmation in an independent cohort.


Subject(s)
Aortic Aneurysm, Abdominal/blood , Aortic Aneurysm, Abdominal/surgery , Carrier Proteins/blood , Extracellular Matrix Proteins/blood , Glycoproteins/blood , Aged , Aortic Aneurysm, Abdominal/diagnostic imaging , Biomarkers/blood , Denmark , Disease Progression , Humans , Male , Predictive Value of Tests , Prospective Studies , Risk Assessment , Risk Factors , Time Factors , Up-Regulation
5.
Int J Mol Sci ; 20(19)2019 Oct 03.
Article in English | MEDLINE | ID: mdl-31623309

ABSTRACT

Amylases are probably the best studied glycoside hydrolases and have a huge biotechnological value for industrial processes on starch. Multiple amylases from fungi and microbes are currently in use. Whereas bacterial amylases are well suited for many industrial processes due to their high stability, fungal amylases are recognized as safe and are preferred in the food industry, although they lack the pH tolerance and stability of their bacterial counterparts. Here, we describe three amylases, two of which have a broad pH spectrum extending to pH 8 and higher stability well suited for a broad set of industrial applications. These enzymes have the characteristic GH13 α-amylase fold with a central (ß/α)8-domain, an insertion domain with the canonical calcium binding site and a C-terminal ß-sandwich domain. The active site was identified based on the binding of the inhibitor acarbose in form of a transglycosylation product, in the amylases from Thamnidium elegans and Cordyceps farinosa. The three amylases have shortened loops flanking the nonreducing end of the substrate binding cleft, creating a more open crevice. Moreover, a potential novel binding site in the C-terminal domain of the Cordyceps enzyme was identified, which might be part of a starch interaction site. In addition, Cordyceps farinosa amylase presented a successful example of using the microseed matrix screening technique to significantly speed-up crystallization.


Subject(s)
Amylases/chemistry , Amylases/metabolism , Fungi/enzymology , Binding Sites , Catalytic Domain , Enzyme Activation , Enzyme Stability , Glucose/chemistry , Glucose/metabolism , Glycosylation , Hydrogen-Ion Concentration , Models, Molecular , Molecular Conformation , Protein Binding , Structure-Activity Relationship , alpha-Amylases/chemistry , alpha-Amylases/metabolism
6.
Acta Crystallogr D Struct Biol ; 75(Pt 1): 1-7, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30644839

ABSTRACT

α-Amylases are glycoside hydrolases that break the α-1,4 bonds in starch and related glycans. The degradation of starch is rendered difficult by the presence of varying degrees of α-1,6 branch points and their possible accommodation within the active centre of α-amylase enzymes. Given the myriad industrial uses for starch and thus also for α-amylase-catalysed starch degradation and modification, there is considerable interest in how different α-amylases might accommodate these branches, thus impacting on the potential processing of highly branched post-hydrolysis remnants (known as limit dextrins) and societal applications. Here, it was sought to probe the branch-point accommodation of the Alicyclobacillus sp. CAZy family GH13 α-amylase AliC, prompted by the observation of a molecule of glucose in a position that may represent a branch point in an acarbose complex solved at 2.1 Šresolution. Limit digest analysis by two-dimensional NMR using both pullulan (a regular linear polysaccharide of α-1,4, α-1,4, α-1,6 repeating trisaccharides) and amylopectin starch showed how the Alicyclobacillus sp. enzyme could accept α-1,6 branches in at least the -2, +1 and +2 subsites, consistent with the three-dimensional structures with glucosyl moieties in the +1 and +2 subsites and the solvent-exposure of the -2 subsite 6-hydroxyl group. Together, the work provides a rare insight into branch-point acceptance in these industrial catalysts.


Subject(s)
Alicyclobacillus/enzymology , alpha-Amylases/chemistry , Acarbose , Glycoside Hydrolase Inhibitors , Magnetic Resonance Spectroscopy , Starch/metabolism , Substrate Specificity
7.
J Cardiovasc Surg (Torino) ; 60(2): 221-229, 2019 Apr.
Article in English | MEDLINE | ID: mdl-28847145

ABSTRACT

BACKGROUND: The role of the intraluminal thrombus (ILT) in abdominal aortic aneurysm (AAA) growth remains incompletely understood. MRI is superior to other methods in depicting the morphology of the ILT. This study brings preliminary, but novel information on the presence and morphological characteristics of the ILT and AAA growth rates in a screening cohort. METHODS: Cohort study with 46 patients from the Viborg Vascular Trial. All underwent one non-contrast-enhanced magnetic resonance imaging (MRI) at the end of follow-up. ILT presence was noted and, if present, it was allocated to one of four morphological categories based on visual appearance and signal intensity on T2 weighted images. RESULTS: The mean growth rate was 1.95 mm/year ±0.87 (SD). The observation time was 5.59±0.63 (SD) years. ILT was present in AAA size groups as follows: 30-34.9 mm 20.00%, 35-39.9 mm 88.89%, 40-44.9 mm 81.25%, 45-49.9 mm 100% and 50-54.9 mm 100%. Out of 46, 8 had no ILT at the time of MRI. The presence of any sort of ILT yielded a significantly increased unadjusted and an adjusted growth rate of 1.09 mm/year (95% CI: 0.48; 1.70) and 1.24 mm/year (95% CI: 0.64; 1.83), respectively. All four thrombus types were retrospectively associated with an increased recorded growth rate compared with "no thrombus". Presence of a thin circumferential thrombus was retrospectively associated with the highest increase in growth rate, viz. 2.09 mm/year (95% CI: 1.23; 2.95). CONCLUSIONS: We observed faster growth rate in those AAA that had developed an ILT. Even faster growth was observed amongst those AAA containing a thin ILT located along the inner circumference.


Subject(s)
Aorta, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/diagnostic imaging , Magnetic Resonance Angiography , Thrombosis/diagnostic imaging , Aged , Aged, 80 and over , Disease Progression , Humans , Male , Predictive Value of Tests , Preliminary Data , Reproducibility of Results , Retrospective Studies , Time Factors , Ultrasonography, Interventional
8.
Arterioscler Thromb Vasc Biol ; 38(9): 2254-2267, 2018 09.
Article in English | MEDLINE | ID: mdl-30002058

ABSTRACT

Objective- Porosity of the intraluminal thrombus (ILT) is believed to convey biologically active components from the bloodstream toward the aneurismal wall. Accumulation of molecules in the abdominal aortic aneurysmatic tissue may influence vascular protein turnover and regulate abdominal aortic aneurysm growth. We sought to identify proteins with concentrations in the ILT and the abdominal aortic aneurysm wall which associate with aneurysmal expansion rate. Approach and Results- Proteomic analysis by liquid chromatography tandem-mass spectrometry of separated wall and ILT samples was correlated with preoperative aneurysmal growth rate in 24 individuals operated electively for infrarenal abdominal aortic aneurysm. The median preoperative growth rate was 3.8 mm/y (interquartile range, 3) and the mean observational time was 3.3±1.7 years. Plasma components dominated the group of proteins with tissue concentrations, which correlate positively with growth rates ( P<0.001, Fisher exact test, both in the ILT and the wall). In contrast, in the wall and thrombus samples, ECM (extracellular matrix) proteins were significantly more prevalent in the group of proteins with negative correlations to growth rates ( P<0.05, Fisher exact test). Similarly, a long series of proteins, related to cellular functions correlated negatively to growth rates. Conclusions- When the preoperative aneurysmatic growth rate has been high, the concentration of many plasma proteins residing in the ILT and the aneurysmatic tissue is also high, compatible with the hypothesis of increased tissue porosity and accumulation of plasma components as a driver of aneurysm expansion. Moreover, many matrix and cellular proteins which are found in high concentrations in slower-growing aneurysms provides new knowledge about potential treatment targets.


Subject(s)
Aorta, Abdominal/pathology , Aortic Aneurysm, Abdominal/blood , Aortic Aneurysm, Abdominal/pathology , Blood Proteins/metabolism , Aged , Chromatography, Liquid , Female , Humans , Male , Porosity , Proteomics , Tandem Mass Spectrometry
9.
J Med Chem ; 60(8): 3472-3483, 2017 04 27.
Article in English | MEDLINE | ID: mdl-28406621

ABSTRACT

A series of potent thienotriazolopyrimidinone-based PDE1 inhibitors was discovered. X-ray crystal structures of example compounds from this series in complex with the catalytic domain of PDE1B and PDE10A were determined, allowing optimization of PDE1B potency and PDE selectivity. Reduction of hERG affinity led to greater than a 3000-fold selectivity for PDE1B over hERG. 6-(4-Methoxybenzyl)-9-((tetrahydro-2H-pyran-4-yl)methyl)-8,9,10,11-tetrahydropyrido[4',3':4,5]thieno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidin-5(6H)-one was identified as an orally bioavailable and brain penetrating PDE1B enzyme inhibitor with potent memory-enhancing effects in a rat model of object recognition memory.


Subject(s)
Memory/drug effects , Phosphodiesterase Inhibitors/pharmacology , Crystallography, X-Ray , Drug Discovery , Phosphodiesterase Inhibitors/chemistry
10.
J Med Chem ; 60(5): 2037-2051, 2017 03 09.
Article in English | MEDLINE | ID: mdl-28165743

ABSTRACT

A series of potent and selective [1,2,4]triazolo[1,5-a]pyrimidine PDE2a inhibitors is reported. The design and improvement of the binding properties of this series was achieved using X-ray crystal structures in conjunction with careful analysis of electronic and structural requirements for the PDE2a enzyme. One of the lead compounds, compound 27 (DNS-8254), was identified as a potent and highly selective PDE2a enzyme inhibitor with favorable rat pharmacokinetic properties. Interestingly, the increased potency of compound 27 was facilitated by the formation of a halogen bond with the oxygen of Tyr827 present in the PDE2a active site. In vivo, compound 27 demonstrated significant memory enhancing effects in a rat model of novel object recognition. Taken together, these data suggest that compound 27 may be a useful tool to explore the pharmacology of selective PDE2a inhibition.


Subject(s)
Exonucleases/drug effects , Memory Disorders/drug therapy , Phosphodiesterase Inhibitors/chemical synthesis , Phosphodiesterase Inhibitors/pharmacology , Chromatography, Liquid , Humans , Proton Magnetic Resonance Spectroscopy
11.
Eur J Pharmacol ; 592(1-3): 158-9, 2008 Sep 11.
Article in English | MEDLINE | ID: mdl-18644363

ABSTRACT

To understand the contribution of the estrogen receptor beta, the potent and selective agonist ERb-131 was evaluated in animal models of inflammatory pain. In paradigms of acute and persistent inflammatory pain, ERb-131 did not alleviate the nociception induced by either carrageenan or formalin. However, in the chronic complete Freund's adjuvant model, ERb-131 resolved both inflammatory and hyperalgesic components. Thus, ERb-131 is sufficient to alleviate chronic but not acute inflammatory pain states.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Estrogen Receptor beta/agonists , Inflammation/drug therapy , Pain/drug therapy , Acute Disease , Animals , Carrageenan , Chronic Disease , Formaldehyde , Freund's Adjuvant , Hyperalgesia/chemically induced , Hyperalgesia/drug therapy , Inflammation/chemically induced , Inflammation/etiology , Male , Pain/chemically induced , Pain/etiology , Pain Measurement/drug effects , Rats , Rats, Sprague-Dawley
12.
Eur J Pharmacol ; 590(1-3): 423-9, 2008 Aug 20.
Article in English | MEDLINE | ID: mdl-18559275

ABSTRACT

The effects of estrogens on pain perception remain controversial. In animal models, both beneficial and detrimental effects of non-selective estrogens have been reported. ERb-131 a non-steroidal estrogen receptor beta ligand was evaluated in several pain animal models involving nerve injury or sensitization. Using functional and binding assays, ERb-131 was characterized as a potent and selective estrogen receptor beta agonist. In vivo, ERb-131 was devoid of estrogen receptor alpha activity as assessed in a rat uterotrophic assay. ERb-131 alleviated tactile hyperalgesia induced by capsaicin, and reversed tactile allodynia caused by spinal nerve ligation and various chemical insults. Moreover, ERb-131 did not influence the pain threshold of normal healthy animals. Thus, estrogen receptor beta agonism is a critical effector in attenuating a broad range of anti-nociceptive states.


Subject(s)
Estrogen Receptor beta/agonists , Pain/drug therapy , Peripheral Nervous System Diseases/drug therapy , Animals , Cells, Cultured , Dose-Response Relationship, Drug , Estradiol/analogs & derivatives , Estradiol/pharmacology , Female , Fulvestrant , Humans , Male , Mice , Mice, Inbred BALB C , Pain Threshold/drug effects , Rats , Rats, Sprague-Dawley , Uterus/drug effects
13.
Nat Chem Biol ; 4(6): 347-56, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18454143

ABSTRACT

Calcium-dependent protein kinases play a crucial role in intracellular calcium signaling in plants, some algae and protozoa. In Plasmodium falciparum, calcium-dependent protein kinase 1 (PfCDPK1) is expressed during schizogony in the erythrocytic stage as well as in the sporozoite stage. It is coexpressed with genes that encode the parasite motor complex, a cellular component required for parasite invasion of host cells, parasite motility and potentially cytokinesis. A targeted gene-disruption approach demonstrated that pfcdpk1 seems to be essential for parasite viability. An in vitro biochemical screen using recombinant PfCDPK1 against a library of 20,000 compounds resulted in the identification of a series of structurally related 2,6,9-trisubstituted purines. Compound treatment caused sudden developmental arrest at the late schizont stage in P. falciparum and a large reduction in intracellular parasites in Toxoplasma gondii, which suggests a possible role for PfCDPK1 in regulation of parasite motility during egress and invasion.


Subject(s)
Adenine/analogs & derivatives , Antimalarials/pharmacology , Cyclohexylamines/pharmacology , Gene Expression Regulation, Enzymologic/genetics , Malaria/parasitology , Plasmodium falciparum/enzymology , Protein Kinases/drug effects , Protein Kinases/genetics , Protozoan Proteins/antagonists & inhibitors , Adenine/chemistry , Adenine/pharmacology , Adenine/therapeutic use , Animals , Antimalarials/chemistry , Antimalarials/therapeutic use , CHO Cells , Cell Line , Cell Proliferation/drug effects , Cricetinae , Cricetulus , Cyclohexylamines/chemistry , Cyclohexylamines/therapeutic use , Drug Evaluation, Preclinical , Enzyme Activation/drug effects , Gene Expression Regulation, Enzymologic/drug effects , HeLa Cells , Humans , Life Cycle Stages/drug effects , Malaria/drug therapy , Malaria/immunology , Male , Mice , Mice, Inbred BALB C , Models, Molecular , Molecular Structure , Molecular Weight , Movement/drug effects , Oligonucleotide Array Sequence Analysis/methods , Parasitic Sensitivity Tests , Plasmodium falciparum/growth & development , Protein Kinases/physiology , Protozoan Proteins/genetics , Protozoan Proteins/physiology , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/genetics , Small Molecule Libraries , Stereoisomerism , Structure-Activity Relationship , Tissue Distribution
14.
ACS Chem Biol ; 3(3): 180-92, 2008 Mar 20.
Article in English | MEDLINE | ID: mdl-18307303

ABSTRACT

Aurora family kinases regulate important events during mitosis including centrosome maturation and separation, mitotic spindle assembly, and chromosome segregation. Misregulation of Aurora kinases due to genetic amplification and protein overexpression results in aneuploidy and may contribute to tumorigenesis. Here we report the discovery of new small molecule aminothiazole inhibitors of Aurora kinases with exceptional kinase selectivity and report a 1.7 A cocrystal structure with the Aurora B:INCENP complex from Xenopus laevis. The compounds recapitulate the hallmarks of Aurora kinase inhibition, including decreased histone H3 serine 10 phosphorylation, failure to complete cytokinesis, and endoreduplication.


Subject(s)
Amines/chemistry , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Thiazoles/chemistry , Thiazoles/pharmacology , Animals , Aurora Kinases , Cyanates/chemistry , Models, Molecular , Molecular Structure , Protein Binding , Protein Serine-Threonine Kinases/chemistry , Sensitivity and Specificity , Structure-Activity Relationship , Xenopus laevis
15.
Mol Pharmacol ; 73(3): 900-8, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18055761

ABSTRACT

Steroidogenic factor SF-1, a constitutively active nuclear hormone receptor, is essential to the development of adrenal and gonadal glands and acts as a shaping factor of sexual determination and differentiation. Its effects are exerted primarily through the control of the synthesis of steroid hormones. The functional cell-based assay Receptor Selection and Amplification Technology (R-SAT) was used to identify potent and selective SF-1 inverse agonists through the screening of a chemical library of drug-like small-molecule entities. Among them, 4-(heptyloxy)phenol (AC-45594), a prototype inverse agonist lead, was used to show that SF-1 constitutive activity can be pharmacologically modulated by a synthetic ligand. In a physiological system of endocrine function, the expression of several reported SF-1 target genes, including SF-1 itself, was inhibited by treatment with AC-45594 and analogs. Thus, pharmacological modulation of SF-1 is critical to its function as an endocrine master regulator and has potentially important consequences to diseases in which SF-1 activity is critical.


Subject(s)
Cholesterol Side-Chain Cleavage Enzyme/genetics , Drug Evaluation, Preclinical/methods , Phenols/pharmacology , Steroidogenic Factor 1/agonists , Steroidogenic Factor 1/chemical synthesis , Adrenal Gland Neoplasms/pathology , Animals , Carcinoma/pathology , Cell Proliferation/drug effects , Cholesterol Side-Chain Cleavage Enzyme/metabolism , Cyclic AMP/pharmacology , Genes, Reporter , Humans , Inhibitory Concentration 50 , Ligands , Luciferases/metabolism , Mice , Mutation , NIH 3T3 Cells , RNA, Messenger/metabolism , Steroidogenic Factor 1/chemistry , Steroidogenic Factor 1/genetics , Transcription, Genetic , Transcriptional Activation , Transfection , Tumor Cells, Cultured
16.
EMBO J ; 25(24): 5716-25, 2006 Dec 13.
Article in English | MEDLINE | ID: mdl-17124499

ABSTRACT

cGMP-inhibited cAMP phosphodiesterase 3A (PDE3A) is expressed in mouse oocytes, and its function is indispensable for meiotic maturation as demonstrated by genetic ablation. Moreover, PDE3 activity is required for insulin/insulin-like growth factor-1 stimulation of Xenopus oocyte meiotic resumption. Here, we investigated the cAMP-dependent protein kinase B (PKB)/Akt regulation of PDE3A and its impact on oocyte maturation. Cell-free incubation of recombinant mouse PDE3A with PKB/Akt or cAMP-dependent protein kinase A catalytic subunits leads to phosphorylation of the PDE3A protein. Coexpression of PDE3A with constitutively activated PKB/Akt (Myr-Akt) increases PDE activity as well as its phosphorylation state. Injection of pde3a mRNA potentiates insulin-dependent maturation of Xenopus oocytes and rescues the phenotype of pde3(-/-) mouse oocytes. This effect is greatly decreased by mutation of any of the PDE3A serines 290-292 to alanine in both Xenopus and mouse. Microinjection of myr-Akt in mouse oocytes causes in vitro meiotic maturation and this effect requires PDE3A. Collectively, these data indicate that activation of PDE3A by PKB/Akt-mediated phosphorylation plays a role in the control of PDE3A activity in mammalian oocytes.


Subject(s)
3',5'-Cyclic-AMP Phosphodiesterases/metabolism , Oocytes/cytology , Oogenesis/physiology , Proto-Oncogene Proteins c-akt/metabolism , 3',5'-Cyclic-AMP Phosphodiesterases/chemistry , 3',5'-Cyclic-AMP Phosphodiesterases/deficiency , Amino Acid Sequence , Animals , Cyclic AMP-Dependent Protein Kinases/metabolism , Cyclic Nucleotide Phosphodiesterases, Type 3 , Enzyme Activation/drug effects , Female , Humans , Insulin/pharmacology , Isoenzymes/metabolism , Maturation-Promoting Factor/metabolism , Mice , Molecular Sequence Data , Oocytes/drug effects , Oogenesis/drug effects , Phenotype , Phosphorylation/drug effects , Phosphoserine/metabolism , Xenopus
17.
Expert Opin Drug Deliv ; 2(5): 927-33, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16296787

ABSTRACT

A few decades ago, chewing gum was rarely considered when industry searched for an applicable delivery vehicle for an active pharmaceutical substance. Yet, the 1980s and 1990s saw gum become the most successful nicotine delivery form; unawareness changed to cautious scepticism, and today the merits of chewing gum drug delivery technologies are generally appreciated. MediChew is the registered trademark of Fertin Pharma's medical chewing gum technology platform. Based on patent-protected technologies, it offers unique taste-masking possibilities and allows control of drug molecule release. Medical chewing gum products based on these technologies are specifically suitable for convenient administration on demand, for active substances providing a topical effect in the oral cavity and throat, and for systemic delivery of drug molecules that readily cross the oromucosal membranes.


Subject(s)
Chewing Gum , Drug Delivery Systems , Excipients , Humans , Pharmaceutical Preparations/administration & dosage
18.
Protein Sci ; 14(3): 743-55, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15722449

ABSTRACT

The mechanism of allosteric activation of alpha-amylase by chloride has been studied through structural and kinetic experiments focusing on the chloride-dependent N298S variant of human pancreatic alpha-amylase (HPA) and a chloride-independent TAKA-amylase. Kinetic analysis of the HPA variant clearly demonstrates the pronounced activating effect of chloride ion binding on reaction rates and its effect on the pH-dependence of catalysis. Structural alterations observed in the N298S variant upon chloride ion binding suggest that the chloride ion plays a variety of roles that serve to promote catalysis. One of these is having a strong influence on the positioning of the acid/base catalyst residue E233. Absence of chloride ion results in multiple conformations for this residue and unexpected enzymatic products. Chloride ion and N298 also appear to stabilize a helical region of polypeptide chain from which projects the flexible substrate binding loop unique to chloride-dependent alpha-amylases. This structural feature also serves to properly orient the catalytically essential residue D300. Comparative analyses show that the chloride-independent alpha-amylases compensate for the absence of bound chloride by substituting a hydrophobic core, altering the manner in which substrate interactions are made and shifting the placement of N298. These evolutionary differences presumably arise in response to alternative operating environments or the advantage gained in a particular product profile. Attempts to engineer chloride-dependence into the chloride-independent TAKA-amylase point out the complexity of this system, and the fact that a multitude of factors play a role in binding chloride ion in the chloride-dependent alpha-amylases.


Subject(s)
Chlorides/metabolism , Pancreas/enzymology , alpha-Amylases/chemistry , Acarbose/metabolism , Amino Acid Sequence , Amino Acid Substitution , Aspergillus oryzae/enzymology , Aspergillus oryzae/genetics , Enzyme Activation/physiology , Humans , Hydrogen Bonding , Kinetics , Mutagenesis , Pancreas/metabolism , Protein Structure, Tertiary , Sequence Alignment , alpha-Amylases/genetics , alpha-Amylases/metabolism
19.
Structure ; 12(3): 487-94, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15016364

ABSTRACT

AvrB is a Pseudomonas syringae type III effector protein that is translocated into host plant cells during attempted pathogenesis. Arabidopsis harboring the corresponding resistance protein RPM1 can detect AvrB and mount a rapid host defense response, thus avoiding active infection. In the plant cell, AvrB induces phosphorylation of RIN4, a key component in AvrB/RPM1 recognition. Although the AvrB/RPM1 system is among the best characterized of the numerous bacterial effector/plant resistance protein systems involved in plant disease resistance and pathogenesis, the details of the molecular recognition mechanism are still unclear. To gain further insights, the crystal structure of AvrB was determined. The 2.2 A structure exhibits a novel mixed alpha/beta bilobal fold. Aided by the structural information, we demonstrate that one lobe is the determinant of AvrB/RPM1 recognition specificity. This structural information and preliminary structure-function studies provide a framework for the future understanding of AvrB function on the molecular level.


Subject(s)
Bacterial Proteins/chemistry , Amino Acid Sequence , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Crystallography, X-Ray , Models, Molecular , Molecular Sequence Data , Protein Folding , Protein Structure, Secondary , Protein Structure, Tertiary , Pseudomonas syringae/chemistry , Pseudomonas syringae/genetics , Pseudomonas syringae/metabolism , Sequence Alignment
20.
Biochem J ; 369(Pt 2): 227-38, 2003 Jan 15.
Article in English | MEDLINE | ID: mdl-12374568

ABSTRACT

In the present study, we have characterized the Xenopus Akt expressed in oocytes from the African clawed frog Xenopus laevis and tested whether its activity is required for the insulin- and progesterone-stimulated resumption of meiosis. A cDNA encoding the Xenopus Akt was isolated and sequenced, and its expression in the Xenopus oocyte was confirmed by reverse transcription PCR and Northern blotting. Using phosphospecific antibodies and enzyme assays, a large and rapid activation of the Xenopus Akt was observed upon insulin stimulation of the oocytes. In contrast, progesterone caused a modest activation of this kinase with a slower time course. To test whether the activation of Akt was required in the stimulation of the resumption of meiosis, we have utilized two independent approaches: a functional dominant negative Akt mutant and an inhibitory monoclonal antibody. Both the mutant Akt, as well as the inhibitory monoclonal antibody, completely blocked the insulin-stimulated resumption of meiosis. In contrast, both treatments only partially inhibited (by approx. 30%) the progesterone-stimulated resumption of meiosis when submaximal doses of this hormone were utilized. These data demonstrate a crucial role for Akt in the insulin-stimulated cell cycle progression of Xenopus oocytes, whereas Akt may have an ancillary function in progesterone signalling.


Subject(s)
Insulin/pharmacology , Meiosis/physiology , Progesterone/pharmacology , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins/metabolism , Xenopus laevis/physiology , Amino Acid Sequence , Animals , Antibodies, Monoclonal/metabolism , COS Cells , Dose-Response Relationship, Drug , Female , Insulin/metabolism , Meiosis/drug effects , Microinjections , Molecular Sequence Data , Oocytes/drug effects , Oocytes/physiology , Phylogeny , Progesterone/metabolism , Proto-Oncogene Proteins/classification , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-akt , RNA, Messenger/metabolism , Sequence Alignment , Signal Transduction/physiology
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