Publications by authors named "Veronica Moreno"

15 Publications

  • Page 1 of 1

A non-homogeneous Markov early epidemic growth dynamics model. Application to the SARS-CoV-2 pandemic.

Chaos Solitons Fractals 2020 Oct 18;139:110297. Epub 2020 Sep 18.

Universidad Nacional de Tres de Febrero, Argentina.

This work introduces a new markovian stochastic model that can be described as a non-homogeneous Pure Birth process. We propose a functional form of birth rate that depends on the number of individuals in the population and on the elapsed time, allowing us to model a contagion effect. Thus, we model the early stages of an epidemic. The number of individuals then becomes the infectious cases and the birth rate becomes the incidence rate. We obtain this way a process that depends on two competitive phenomena, infection and immunization. Variations in those rates allow us to monitor how effective the actions taken by government and health organizations are. From our model, three useful indicators for the epidemic evolution over time are obtained: the immunization rate, the infection/immunization ratio and the mean time between infections (MTBI). The proposed model allows either positive or negative concavities for the mean value curve, provided the infection/immunization ratio is either greater or less than one. We apply this model to the present SARS-CoV-2 pandemic still in its early growth stage in Latin American countries. As it is shown, the model accomplishes a good fit for the real number of both positive cases and deaths. We analyze the evolution of the three indicators for several countries and perform a comparative study between them. Important conclusions are obtained from this analysis.
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http://dx.doi.org/10.1016/j.chaos.2020.110297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7500902PMC
October 2020

SNCA and mTOR Pathway Single Nucleotide Polymorphisms Interact to Modulate the Age at Onset of Parkinson's Disease.

Mov Disord 2019 09 24;34(9):1333-1344. Epub 2019 Jun 24.

Department of Biomedicine, Unit of Biochemistry, Universitat de Barcelona, Barcelona, Catalonia, Spain.

Background: Single nucleotide polymorphisms (SNPs) in the α-synuclein (SNCA) gene are associated with differential risk and age at onset (AAO) of both idiopathic and Leucine-rich repeat kinase 2 (LRRK2)-associated Parkinson's disease (PD). Yet potential combinatory or synergistic effects among several modulatory SNPs for PD risk or AAO remain largely underexplored.

Objectives: The mechanistic target of rapamycin (mTOR) signaling pathway is functionally impaired in PD. Here we explored whether SNPs in the mTOR pathway, alone or by epistatic interaction with known susceptibility factors, can modulate PD risk and AAO.

Methods: Based on functional relevance, we selected a total of 64 SNPs mapping to a total of 57 genes from the mTOR pathway and genotyped a discovery series cohort encompassing 898 PD patients and 921 controls. As a replication series, we screened 4170 PD and 3014 controls available from the International Parkinson's Disease Genomics Consortium.

Results: In the discovery series cohort, we found a 4-loci interaction involving STK11 rs8111699, FCHSD1 rs456998, GSK3B rs1732170, and SNCA rs356219, which was associated with an increased risk of PD (odds ratio = 2.59, P < .001). In addition, we also found a 3-loci epistatic combination of RPTOR rs11868112 and RPS6KA2 rs6456121 with SNCA rs356219, which was associated (odds ratio = 2.89; P < .0001) with differential AAO. The latter was further validated (odds ratio = 1.56; P = 0.046-0.047) in the International Parkinson's Disease Genomics Consortium cohort.

Conclusions: These findings indicate that genetic variability in the mTOR pathway contributes to SNCA effects in a nonlinear epistatic manner to modulate differential AAO in PD, unraveling the contribution of this cascade in the pathogenesis of the disease. © 2019 International Parkinson and Movement Disorder Society.
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http://dx.doi.org/10.1002/mds.27770DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7322732PMC
September 2019

[Medical audit guideline about rheumatoid arthritis diagnosis and treatment.]

Rev Fac Cien Med Univ Nac Cordoba 2019 02 27;76(1):68-76. Epub 2019 Feb 27.

Hospital Italiano de Córdoba.

Introduction: rheumatoid arthritis is a frequent inflammatory disease and a leading cause of potentially-treatable disability. Rheumatoid arthritis is associated with an increased risk of general morbidity and mortality. New therapeutic options have dramatically improved the evolution of patients.

Objectives: in this joint work of the Association of Auditing and Quality of Medical Care of Córdoba (ASACAM) and the Argentine Society of Rheumatology (SAR), we generated recommendations to especially assist medical auditors in making decisions to improve the quality of the medical and life care of patients and reduce costs in the management of rheumatoid arthritis patients. in addition to medical auditors, these recommendations can be expanded to general practitioners, rheumatologists and clinicians, and eventually to the general public. Conclusions: suggestions for the diagnosis and treatment of patients with rheumatoid arthritis (including biological therapies) are described, based on the Clinical Practice Guidelines for the Treatment of Rheumatoid Arthritis (SAR, 2013), the resolutions of the Compulsory Medical Program and the Unique Reimbursement System currently used in

Intended Population: in addition to medical auditors, these recommendations can be expanded to general practitioners, rheumatologists and clinicians, and eventually to the general public.

Conclusions: suggestions for the diagnosis and treatment of patients with rheumatoid arthritis (including biological therapies) are described, based on the Clinical Practice Guidelines for the Treatment of Rheumatoid Arthritis (SAR, 2013), the resolutions of the Compulsory Medical Program and the Unique Reimbursement System currently used in Argentina.
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http://dx.doi.org/10.31053/1853.0605.v76.n1.22218DOI Listing
February 2019

A Long-Acting PYY Analog Mediates Robust Anorectic Efficacy with Minimal Emesis in Nonhuman Primates.

Cell Metab 2019 04 14;29(4):837-843.e5. Epub 2019 Feb 14.

Discovery Biology, Cardiovascular and Metabolic Therapeutic Areas, Janssen Research and Development, Spring House, PA, USA. Electronic address:

The gut hormone PYY reduces food intake in humans and exhibits at least additive efficacy in combination with GLP-1. However, the utility of PYY analogs as anti-obesity agents has been severely limited by emesis and rapid proteolysis, a profile similarly observed with native PYY in obese rhesus macaques. Here, we found that antibody conjugation of a cyclized PYY analog achieved high NPY2R selectivity, unprecedented in vivo stability, and gradual infusion-like exposure. These properties permitted profound reduction of food intake when administered to macaques for 23 days without a single emetic event in any animal. Co-administration with the GLP-1 receptor agonist liraglutide for an additional 5 days further reduced food intake with only one animal experiencing a single bout of emesis. This antibody-conjugated PYY analog therefore may enable the long-sought potential of GLP-1/PYY-based combination treatment to achieve robust, well-tolerated weight reduction in obese patients.
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http://dx.doi.org/10.1016/j.cmet.2019.01.017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6701930PMC
April 2019

MTOR Pathway-Based Discovery of Genetic Susceptibility to L-DOPA-Induced Dyskinesia in Parkinson's Disease Patients.

Mol Neurobiol 2019 Mar 10;56(3):2092-2100. Epub 2018 Jul 10.

Department of Biomedicine, Unit of Biochemistry, Faculty of Medicine, Universitat de Barcelona, 08036, Barcelona, Catalonia, Spain.

Dyskinesia induced by L-DOPA administration (LID) is one of the most invalidating adverse effects of the gold standard treatment restoring dopamine transmission in Parkinson's disease (PD). However, LID manifestation in parkinsonian patients is variable and heterogeneous. Here, we performed a candidate genetic pathway analysis of the mTOR signaling cascade to elucidate a potential genetic contribution to LID susceptibility, since mTOR inhibition ameliorates LID in PD animal models. We screened 64 single nucleotide polymorphisms (SNPs) mapping to 57 genes of the mTOR pathway in a retrospective cohort of 401 PD cases treated with L-DOPA (70 PD with moderate/severe LID and 331 with no/mild LID). We performed classic allelic, genotypic, and epistatic analyses to evaluate the association of individual or combinations of SNPs with LID onset and with LID severity after initiation of L-DOPA treatment. As for the time to LID onset, we found significant associations with SNP rs1043098 in the EIF4EBP2 gene and also with an epistatic interaction involving EIF4EBP2 rs1043098, RICTOR rs2043112, and PRKCA rs4790904. For LID severity, we found significant association with HRAS rs12628 and PRKN rs1801582 and also with a four-loci epistatic combination involving RPS6KB1 rs1292034, HRAS rs12628, RPS6KA2 rs6456121, and FCHSD1 rs456998. These findings indicate that the mTOR pathway contributes genetically to LID susceptibility. Our study could help to identify the most susceptible PD patients to L-DOPA in order to prevent the appearance of early and/or severe LID in a future. This information could also be used to stratify PD patients in clinical trials in a more accurate way.
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http://dx.doi.org/10.1007/s12035-018-1219-1DOI Listing
March 2019

Immunological memory to hyperphosphorylated tau in asymptomatic individuals.

Acta Neuropathol 2017 05 24;133(5):767-783. Epub 2017 Mar 24.

Janssen Prevention Center, Janssen Pharmaceutical Companies of Johnson & Johnson, 2 Royal College Street, London, NW1 0NH, UK.

Several reports have described the presence of antibodies against Alzheimer's disease-associated hyperphosphorylated forms of tau in serum of healthy individuals. To characterize the specificities that can be found, we interrogated peripheral IgG memory B cells from asymptomatic blood donors for reactivity to a panel of phosphorylated tau peptides using a single-cell screening assay. Antibody sequences were recovered, cloned, and expressed as full-length IgGs. In total, 52 somatically mutated tau-binding antibodies were identified, corresponding to 35 unique clonal families. Forty-one of these antibodies recognize epitopes in the proline-rich and C-terminal domains, and binding of 26 of these antibodies is strictly phosphorylation dependent. Thirteen antibodies showed inhibitory activity in a P301S lysate seeded in vitro tau aggregation assay. Two such antibodies, CBTAU-7.1 and CBTAU-22.1, which bind to the proline-rich and C-terminal regions of tau, respectively, were characterized in more detail. CBTAU-7.1 recognizes an epitope that is similar to that of murine anti-PHF antibody AT8, but has different phospho requirements. Both CBTAU-7.1 and CBTAU-22.1 detect pathological tau deposits in post-mortem brain tissue. CBTAU-7.1 reveals a similar IHC distribution pattern as AT8, immunostaining (pre)tangles, threads, and neuritic plaques. CBTAU-22.1 shows selective detection of neurofibrillary changes by IHC. Taken together, these results suggest the presence of an ongoing antigen-driven immune response against tau in healthy individuals. The wide range of specificities to tau suggests that the human immune repertoire may contain antibodies that can serve as biomarkers or be exploited for therapy.
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http://dx.doi.org/10.1007/s00401-017-1705-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5390017PMC
May 2017

A single case report of MR-guided focused ultrasound thalamotomy for tremor in fragile X-associated tremor/ataxia.

Parkinsonism Relat Disord 2016 07 4;28:159-60. Epub 2016 Apr 4.

Parkinson's Disease and Movement Disorders Unit, Hospital Clinic, University of Barcelona, Villarroel 170, 08036, Barcelona, Spain; Institut d'investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Villarroel 170, 08036, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Spain. Electronic address:

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http://dx.doi.org/10.1016/j.parkreldis.2016.04.002DOI Listing
July 2016

Effects of meal size on the release of GLP-1 and PYY after Roux-en-Y gastric bypass surgery in obese subjects with or without type 2 diabetes.

Obes Surg 2014 Nov;24(11):1969-74

Janssen Research & Development, LLC, 3210 Merryfield Row, San Diego, CA, 92121, USA,

Changes in gastrointestinal peptide release may play an important role in improving glucose control and reducing body weight following Roux-en-Y gastric bypass (RYGB), but the impact of low caloric intake on gut peptide release post-surgery has not been well characterized. The purpose of this study was to assess the relationships between low caloric intake and gut peptide release and how they were altered by RYGB. Obese females including ten normoglycemic (ON) and ten with type 2 diabetes mellitus (T2DM) (OD) were studied before, 1 week, and 3 months after RYGB. Nine lean, normoglycemic women were studied for comparison. Subjects were given three separate mixed meal challenges (MMCs; 75, 150, and 300 kcal). Plasma glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) were analyzed. Prior to surgery, only minimal increases in GLP-1 and PYY were observed in response to the MMCs. After surgery, the peak GLP-1 concentration was progressively elevated in response to increasing meal sizes. The meal sizes had a statistically significant impact on elevation of GLP-1 incremental areas under the curve (ΔAUC) in both ON and OD at 1 week and 3 months post-surgery visits (p < 0.05 for all comparisons). The PYY ∆AUC was also significantly increased in a meal size-dependent manner in both ON and OD at both post-surgery visits (p < 0.05 for all comparisons). Meal sizes as small as 75-300 kcal, which cause minimal stimulation in GLP-1 or PYY release in the subjects before RYGB, are sufficient to provide statistically significant, meal size-dependent increases in the peptides post-RYGB both acutely and after meaningful weight loss occurred.
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http://dx.doi.org/10.1007/s11695-014-1316-9DOI Listing
November 2014

JNJ-26070109 [(R)4-bromo-N-[1-(2,4-difluoro-phenyl)-ethyl]-2-(quinoxaline-5-sulfonylamino)-benzamide]: a novel, potent, and selective cholecystokinin 2 receptor antagonist with good oral bioavailability.

J Pharmacol Exp Ther 2011 Jul 14;338(1):328-36. Epub 2011 Apr 14.

Johnson & Johnson Pharmaceutical Research & Development, LLC San Diego, California 92101, USA.

JNJ-26070109 [(R)4-bromo-N-[1-(2,4-difluoro-phenyl)-ethyl]-2-(quinoxaline-5-sulfonylamino)-benzamide] is a representative of a new chemical class of competitive antagonists of cholecystokinin 2 (CCK2) receptors. In this study, the primary in vitro pharmacology of JNJ-26070109 was evaluated along with the pharmacokinetic and pharmacodynamic properties of this compound in rat and canine models of gastric acid secretion. JNJ-26070109 expressed high affinity for human (pK(I) = 8.49 ± 0.13), rat (pK(I) = 7.99 ± 0.08), and dog (pK(I) = 7.70 ± 0.14) CCK2 receptors. The selectivity of JNJ-26070109 at the CCK2 receptor versus the CCK1 receptor was species-dependent, with the greatest degree of selectivity (>1200-fold) measured at the human isoforms of the CCK1 receptor (selectivity at CCK2 versus CCK1 receptors: human, ∼1222-fold; rat, ∼324-fold; dog ∼336-fold). JNJ-26070109 behaved as a surmountable, competitive, antagonist of human CCK2 receptors in a calcium mobilization assay (pK(B) = 8.53 ± 0.05) and in pentagastrin-stimulated gastric acid secretion in the isolated, lumen-perfused, mouse stomach assay (pK(B) = 8.19 ± 0.13). The pharmacokinetic profile of this compound was determined in vivo in rats and dogs. JNJ-26070109 was shown to have high oral bioavailability (%F rat = 73 ± 16; %F dog = 92 ± 12) with half lives of 1.8 ± 0.3 and 1.2 ± 0.1 h in rat and dog, respectively. The pharmacodynamic properties of this compound were investigated using two in vivo models. In conscious rat and dog chronic gastric fistula models of pentagastrin-stimulated acid secretion, JNJ-26070109 had oral EC(50) values of 1.5 and 0.26 μM, respectively. Overall, we have demonstrated that JNJ-26070109 is a high-affinity, selective CCK2 receptor antagonist with good pharmacokinetic properties.
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http://dx.doi.org/10.1124/jpet.110.178483DOI Listing
July 2011

Vitamin A deficiency increases protein catabolism and induces urea cycle enzymes in rats.

J Nutr 2010 Apr 24;140(4):792-8. Epub 2010 Feb 24.

Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Valencia, Valencia, Spain.

Chronic vitamin A deficiency induces a substantial delay in the rates of weight and height gain in both humans and experimental animals. This effect has been associated with an impaired nutrient metabolism and loss of body protein. Therefore, we analyzed the effect of vitamin A deficiency on endogenous proteolysis and nitrogen metabolism and its reversibility with all-trans retinoic acid (RA). Male weanling rats, housed in pairs, were pair-fed a vitamin A-deficient (VAD) or control diet until they were 60 d old. A group of deficient rats were further treated with daily intraperitoneal injections of all-trans RA for 10 d. Final body and tissue (i.e. liver and heart) weights were significantly lower and tissue:body weight ratios were similar in VAD rats and in controls. Conversely, the epididymal white fat:body weight ratio and the plasma concentrations of alanine aminotransferase and adiponectin were significantly higher in VAD rats, which also had hepatic macrovesicular lipid accumulations. Plasma and gastrocnemius muscle 3-methylhistidine, urine nitrogen, and plasma and urine urea concentrations were all significantly higher in the VAD group. The expression of the genes encoding urea cycle enzymes and their activities increased in VAD livers. These changes were partially reverted by all-trans RA. We propose that fuel partitioning in vitamin A deficiency may shift from fatty acids to protein catabolism as an energy source. Our results emphasize the importance of vitamin A on the energy balance control system and they provide an explanation for the role of vitamin A in protein turnover, development, and growth.
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http://dx.doi.org/10.3945/jn.109.119388DOI Listing
April 2010

3-[5-(3,4-Dichloro-phenyl)-1-(4-methoxy-phenyl)-1H-pyrazol-3-yl]-2-m-tolyl-propionate (JNJ-17156516), a novel, potent, and selective cholecystokinin 1 receptor antagonist: in vitro and in vivo pharmacological comparison with dexloxiglumide.

J Pharmacol Exp Ther 2007 Nov 7;323(2):562-9. Epub 2007 Aug 7.

Johnson & Johnson Pharmaceutical Research & Development L.L.C., San Diego, California 92121, USA.

3-[5-(3,4-Dichloro-phenyl)-1-(4-methoxy-phenyl)-1H-pyrazol-3-yl]-2-m-tolyl-propionate (JNJ-17156516) is a novel, potent, and selective cholecystokinin (CCK)1-receptor antagonist. In this study, the pharmacology of JNJ-17156516 was investigated both in vitro and in vivo, and the pharmacokinetic profile was evaluated in rats. JNJ-17156516 expressed high-affinity at the cloned human (pK(I) = 7.96 +/- 0.11), rat (pK(I) = 8.02 +/- 0.11), and canine (pK(I) = 7.98 +/- 0.04) CCK1 receptors, and it was also highly selective for the CCK1 receptor compared with the CCK2 receptor across the same species ( approximately 160-, approximately 230-, and approximately 75-fold, respectively). The high affinity of JNJ-17156516 at CCK1 receptors in vitro was confirmed in radioligand binding studies on fresh human gallbladder tissue (pK(I) = 8.22 +/- 0.05). In a functional in vitro assay of guinea pig gallbladder contraction, JNJ-17156516 behaved as a competitive antagonist, with a pK(B) value of 8.00 +/- 0.07. In vivo, JNJ-17156516 produced a parallel, rightward shift in the CCK-8S-evoked contraction of the guinea pig gallbladder. The dose required to shift the CCK-8S dose-response curve was 240 nmol kg(-1) i.v. In the anesthetized rat, JNJ-17156516 produced a dose-related decrease in the number of duodenal contractions evoked by infusion of CCK-8S, with an ED(50) = 484 nmol kg(-1). Pharmacokinetic analysis of JNJ-17156516 in rats, revealed that JNJ-17156516 had a half-life of 3.0 +/- 0.5 h and a very high bioavailability (108 +/- 10%) in this species. Overall, we have demonstrated that JNJ-17156516 is a high-affinity selective human CCK1 receptor antagonist with good pharmacokinetic properties in rats.
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http://dx.doi.org/10.1124/jpet.107.124578DOI Listing
November 2007

Pharmacological analysis of CCK2 receptors up-regulated using engineered transcription factors.

Regul Pept 2005 Jul;129(1-3):227-32

Johnson & Johnson Pharmaceutical Research & Development, LLC., 3210 Merryfield Row, San Diego, CA, 92121, USA.

Designed zinc finger proteins (ZFPs) regulate expression of target genes when coupled to activator or repressor domains. Transfection of ZFPs into cell lines can create expression systems where the targeted endogenous gene is transcribed and the protein of interest can be investigated in its own cellular context. Here we describe the pharmacological investigation of an expression system generated using CCK2 receptor-selective ZFPs transfected into human embryonic kidney cells (HEKZFP system). The receptors expressed in this system, in response to ZFP expression, were functional in calcium mobilization studies and the potency of the agonists investigated was consistent with their action at CCK2 receptors (CCK-8S pA50 = 9.05+/-0.11, pentagastrin pA50 = 9.11+/-0.13). In addition, binding studies were conducted using [125I]-BH-CCK-8S as radioligand. The saturation binding analysis of this radioligand was consistent with a single population of high affinity CCK receptors (pK(D) = 10.24). Competition studies were also conducted using a number of previously well-characterized CCK-receptor selective ligands; JB93182, YF476, PD-134,308, SR27897, dexloxiglumide, L-365,260 and L-364,718. Overall, the estimated affinity values for these ligands were consistent with their interaction at CCK2 receptors. Therefore, CCK2 receptors up-regulated using zinc finger protein technology can provide an alternative to standard transfection techniques for the pharmacological analysis of compounds.
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http://dx.doi.org/10.1016/j.regpep.2005.02.013DOI Listing
July 2005

Molecular cloning, expression and pharmacological characterization of the canine cholecystokinin 1 receptor.

Br J Pharmacol 2005 Jun;145(3):374-84

Johnson & Johnson Pharmaceutical Research & Development, L.L.C, 3210 Merryfield Row, San Diego, CA 92121, USA.

1 The full-length, canine cholecystokinin 1 (CCK1) receptor was cloned from gallbladder tissue using RT-PCR with a combination of primers designed to interact with conserved regions of the human and rat CCK1 receptor, which also shared homology with the canine genomic sequence. 2 Analysis of the sequence of the canine CCK1 receptor revealed a 1287 base pair product, which encoded a 429 amino-acid protein. This protein was 89% identical to the human and 85% identical to the rat CCK1 receptor. 3 The canine CCK1 receptor was expressed in CHO-K cells for pharmacological characterization. In competition studies, using [(125)I]BH-CCK-8S as radioligand, the affinity values estimated for CCK receptor-selective compounds were not significantly different between the canine and human CCK1 receptors (pK(I)+/-s.e.m. at canine CCK1 receptor; L-364,718=8.82+/-0.08, L-365,260=6.61+/-0.05, YF476=7.91+/-0.15, YM022=8.28+/-0.06 and dexloxiglumide=7.53+/-0.11). Furthermore, the selectivity of these compounds between canine CCK1 and CCK2 receptors was consistent with the selectivity between the human CCK1 and CCK2 receptors. 4 Two additional forms of the canine CCK1 receptor were identified during the cloning procedure. These had three (variant #1) and six (variant #2) amino-acid differences from the wild-type canine CCK1 receptor. Variant #1 bound [(125)I]BH-CCK-8S and displayed an identical pharmacological profile to the wild-type receptor using the ligands described above. No significant binding was measured with variant #2. 5 In conclusion, we have cloned and pharmacologically characterized the canine CCK1 receptor. The data obtained will facilitate the interpretation of numerous pharmacological experiments that have been performed using canine tissue to elucidate the actions of CCK and gastrin.
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http://dx.doi.org/10.1038/sj.bjp.0706196DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1576148PMC
June 2005

Cell lines for drug discovery: elevating target-protein levels using engineered transcription factors.

J Biomol Screen 2004 Feb;9(1):44-51

Sangamo BioSciences, Inc., Point Richmond Technology Center, Richmond, CA 94804, USA.

Drug discovery requires high-quality, high-throughput bioassays for lead identification and optimization. These assays are usually based on immortalized cell lines, which express the selected drug target either naturally or as a consequence of transfection with the cDNA encoding the target. Natural untransfected cell lines often fail to achieve the levels of expression required to provide assays of sufficient quality with a high enough signal-to-noise ratio. Unfortunately, the use of cDNA is increasingly restricted, as the sequences for more and more genes become subject to patent restrictions. To overcome these limitations, the authors demonstrate that engineered transcription factors with Cys2-His2 zinc finger DNA-binding domains can be used to effectively activate an endogenous gene of interest without the use of isolated cDNA of the target gene. Using this approach, the authors have generated a cell line that provides a high-quality and pharmacologically validated G-protein-coupled receptor bioassay. In principle, this technology is applicable to any gene of pharmaceutical importance in any cell type.
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http://dx.doi.org/10.1177/1087057103260115DOI Listing
February 2004

Catalytic activity of ADAM8, ADAM15, and MDC-L (ADAM28) on synthetic peptide substrates and in ectodomain cleavage of CD23.

J Biol Chem 2003 Aug 30;278(33):30469-77. Epub 2003 May 30.

Johnson & Johnson Pharmaceutical Research and Development, San Diego, California 92121, USA.

The ADAM family of disintegrin metalloproteases plays important roles in "ectodomain shedding," the process by which biologically active, soluble forms of cytokines, growth factors, and their receptors are released from membrane-bound precursors. Whereas ADAM8, ADAM15, and MDC-L (ADAM28) are expressed in specific cell types and tissues, their in vivo functions and substrates are not known. By screening a library of synthetic peptides as potential substrates, we show that soluble recombinant forms of these enzymes have similar proteolytic substrate specificity, clearly distinct from that of ADAM17 (TNFalpha-converting enzyme). A number of tumor necrosis factor (TNF) family proteins and CD23 were screened as potential substrates for ectodomain cleavage. We found that ADAM8, ADAM15, and MDC-L, but not ADAM17, catalyzed ectodomain shedding of CD23, the low affinity IgE receptor. ADAM8-dependent, soluble CD23 release required proteolytically active ADAM8, and a physical association of ADAM8 was observed with the membrane-bound form of CD23. The ADAM8-dependent release of sCD23 and the endogenous release from B cell lines could be similarly inhibited by a hydroxamic acid, metalloprotease inhibitor compound. We conclude that ADAM8 could contribute to ectodomain shedding of CD23 and may thus be a potential target for therapeutic intervention in allergy and inflammation.
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http://dx.doi.org/10.1074/jbc.M213157200DOI Listing
August 2003
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