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1.
Mar Pollut Bull ; 179: 113659, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35483245

ABSTRACT

Microplastics (MPs) are widely distributed in marine ecosystems, and their ubiquitous presence is raising concern, particularly about possible impacts on fisheries resources. In tropical regions, shellfish fisheries represent an essential source of income and subsistence for traditional communities, and adverse effects on these resources may have severe consequences on human health. In the present study, bivalve molluscs of the species Anomalocardia flexuosa, captured in the region of the Itapessoca estuary in Pernambuco, Brazil, were analysed. A total of 90% of the individuals presented MP particles in their tissue. We observed an average of 5.15 ± 3.80 MP particles per individual, and for each gram of soft tissue, 3.66 ± 2.59 MP particles were found. Our results showed that MPs are present in clams captured on the Pernambuco coast and that the species studied proved to be suitable for monitoring the levels of microplastic pollution.


Subject(s)
Bivalvia , Water Pollutants, Chemical , Animals , Brazil , Ecosystem , Environmental Monitoring , Humans , Microplastics , Plastics/analysis , Water Pollutants, Chemical/analysis
2.
Clin Exp Allergy ; 47(12): 1661-1670, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28756650

ABSTRACT

BACKGROUND: German cockroach (GCr) allergen extracts are complex and heterogeneous products, and methods to better assess their potency and composition are needed for adequate studies of their safety and efficacy. OBJECTIVE AND METHODS: The objective of this study was to develop an assay based on liquid chromatography and multiple reaction monitoring mass spectrometry (LC-MRM MS) for rapid, accurate, and reproducible quantification of 5 allergens (Bla g 1, Bla g 2, Bla g 3, Bla g 4, and Bla g 5) in crude GCr allergen extracts. RESULTS: We first established a comprehensive peptide library of allergens from various commercial extracts as well as recombinant allergens. Peptide mapping was performed using high-resolution MS, and the peptide library was then used to identify prototypic and quantotypic peptides to proceed with MRM method development. Assay development included a systematic optimization of digestion conditions (buffer, digestion time, and trypsin concentration), chromatographic separation, and MS parameters. Robustness and suitability were assessed following ICH (Q2 [R1]) guidelines. The method is precise (RSD < 10%), linear over a wide range (r > 0.99, 0.01-1384 fmol/µL), and sensitive (LLOD and LLOQ <1 fmol/µL). Having established the parameters for LC-MRM MS, we quantified allergens from various commercial GCr extracts and showed considerable variability that may impact clinical efficacy. CONCLUSIONS AND CLINICAL RELEVANCE: Our data demonstrate that the LC-MRM MS method is valuable for absolute quantification of allergens in GCr extracts and likely has broader applicability to other complex allergen extracts. Definitive quantification provides a new standard for labelling of allergen extracts, which will inform patient care, enable personalized therapy, and enhance the efficacy of immunotherapy for environmental and food allergies.


Subject(s)
Allergens/analysis , Allergens/immunology , Blattellidae/immunology , Mass Spectrometry , Animals , Chromatography, Liquid , Complex Mixtures/analysis , Complex Mixtures/immunology , Epitope Mapping , Humans , Mass Spectrometry/methods , Peptide Library , Peptides/analysis , Peptides/immunology , Reproducibility of Results
3.
Chem Sci ; 7(6): 3869-3878, 2016 Jun 01.
Article in English | MEDLINE | ID: mdl-30155031

ABSTRACT

We present a summary of the National Compound Collection (NCC) pilot; which harvested chemical structure data from 746 publicly-available PhD theses to create an enhanced database of diverse and interesting (largely organic) molecular entities. The database comprised ∼75 000 structure entries, of which 70% were new to ChemSpider at the time of upload. The dataset was evaluated for structural uniqueness by twelve external drug discovery groups from the pharmaceutical, biotech, academic and not-for-profit sectors. These partners generated data reported here comparing the NCC pilot with their in-house compound collections. The proportion of NCC structures considered to be useful for drug discovery ranged from 5-80% depending on the strictness of the filters used; most interestingly from a drug discovery standpoint ∼13k NCC compounds (18% of the NCC) passed the filters and were of good diversity. These compounds are quite different from those that are already present in the screening collections but not so different that they are no longer considered to be drug-like. In general, the drug discovery teams would consider these compounds to be high value molecules for inclusion in their screening collections. This pilot addressed the potential value of unpublished data and explored the practicalities of large-scale data extraction, to inform both retrospective and prospective extraction of chemical data from theses.

4.
West Afr J Med ; 30(2): 99-103, 2011.
Article in English | MEDLINE | ID: mdl-21984456

ABSTRACT

BACKGROUND: Body mass index is often used to assess adiposity but it does not differentiate between fat and non-fat components of body mass. However, body fat composition may be assessed using bioelectrical impedance analysis. OBJECTIVE: The study aimed to relate body mass index to fat in the assessment of overweight and obesity among adolescent Nigerians. METHODS: Adolescent pupils aged 10 years to 18 years from randomly selected secondary schools in Lagos, Nigeria were studied. Body mass index was calculated while percentage body fat was measured using Tanita body® fat scale model BF 681. Overweight and obesity were defined using age and sex specific criteria for body mass index and for body fat. RESULTS: There were 753 pupils {377(50.1%) males and 376(49.9%) females}. The overall mean values of body mass index for males and females were 18.1±2.72 and 18.9±3.41 (p < 0.05) respectively. The corresponding figures for body fat were 9.5±4.48 and 18.9±7.51 (p<0.05) respectively. About three quarters (76.2%) of the females who had body mass index in the overweight and obesity range had high body fat in comparison to 44.4% of males (p < 0.05). CONCLUSION: Body mass index is more related to body fat in adolescent females than in their male counterparts.


Subject(s)
Adipose Tissue/anatomy & histology , Black People , Body Composition , Body Mass Index , Electric Impedance , Adolescent , Child , Female , Humans , Male , Nigeria/epidemiology , Obesity/epidemiology , Overweight/epidemiology , Prevalence , Sex Distribution , Urban Population
5.
Bioorg Med Chem Lett ; 21(19): 5939-43, 2011 Oct 01.
Article in English | MEDLINE | ID: mdl-21885277

ABSTRACT

The discovery of a series of highly potent and novel TLR7 agonist interferon inducers is described. Structure-activity relationships are presented, along with pharmacokinetic studies of a lead molecule from this series of N9-pyridylmethyl-8-oxo-3-deazapurine analogues. A rationale for the very high potency observed is offered. An investigation of the clearance mechanism of this class of compounds in rat was carried out, resulting in aldehyde oxidase mediated oxidation being identified as a key component of the high clearance observed. A possible solution to this problem is discussed.


Subject(s)
Antiviral Agents/chemical synthesis , Antiviral Agents/pharmacology , Hepacivirus/drug effects , Hepatitis C/drug therapy , Interferons/agonists , Toll-Like Receptor 7/agonists , Aldehyde Oxidase/metabolism , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacokinetics , Dose-Response Relationship, Drug , Drug Discovery , Drug Evaluation, Preclinical , Hepacivirus/physiology , Hepatitis C/virology , Humans , Injections, Intravenous , Interferon Inducers/chemical synthesis , Interferon Inducers/chemistry , Interferon Inducers/pharmacokinetics , Interferon Inducers/pharmacology , Microsomes, Liver/metabolism , Molecular Targeted Therapy , Molecular Weight , Purines/chemical synthesis , Purines/metabolism , Rats , Solubility , Stereoisomerism , Structure-Activity Relationship
6.
Trends Parasitol ; 27(12): 523-9, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21943801

ABSTRACT

The 'hygiene hypothesis', or lack of microbial and parasite exposure during early life, is postulated as an explanation for the recent increase in autoimmune and allergic diseases in developed countries. The favored mechanism is that microbial and parasite-derived products interact directly with pathogen recognition receptors to subvert proinflammatory signaling via T regulatory cells, thereby inducing anti-inflammatory effects and control of autoimmune disease. Parasites, such as helminths, are considered to have a major role in the induction of immune regulatory mechanisms among children living in developing countries. Invoking Occam's razor, we believe we can select an alternative mechanism to explain the hygiene hypothesis, based on antibody-mediated inhibition of immune responses that may more simply explain the available evidence.


Subject(s)
Antibodies/immunology , Autoimmune Diseases/immunology , Hygiene Hypothesis , Hypersensitivity/immunology , T-Lymphocytes, Regulatory/immunology , Adaptive Immunity/immunology , Animals , Antigen-Antibody Complex/immunology , Child , Developed Countries , Developing Countries , Humans , Hypergammaglobulinemia/complications , Hypergammaglobulinemia/immunology , Models, Immunological , Parasites/immunology , Parasitic Diseases/immunology
7.
Bioorg Med Chem Lett ; 21(21): 6515-8, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21924901

ABSTRACT

A series of acidic triazoles with activity as soluble guanylate cyclase stimulators is described. Incorporation of the CF(3) triazole improved the overall physicochemical and drug-like properties of the molecule and is exemplified by compound 25.


Subject(s)
Acids/chemistry , Enzyme Activators/pharmacology , Guanylate Cyclase/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Triazoles/pharmacology , Soluble Guanylyl Cyclase , Triazoles/chemistry
8.
Bioorg Med Chem Lett ; 21(11): 3404-6, 2011 Jun 01.
Article in English | MEDLINE | ID: mdl-21515054

ABSTRACT

Heteroarylalanine derivatives 4 were designed as potential inhibitors of neutral endopeptidase (NEP EC 3.4.24.11). Selectivity over other zinc metalloproteinases was explored through occupation of the S2' subsite within NEP. Structural optimisation led to the identification of 5-phenyl oxazole 4f, a potent and selective NEP inhibitor. A crystal structure of the inhibitor bound complex is reported.


Subject(s)
Acids/chemical synthesis , Alanine/chemical synthesis , Neprilysin/antagonists & inhibitors , Oxazoles/chemistry , Oxazoles/pharmacology , Protease Inhibitors/chemical synthesis , Protease Inhibitors/pharmacology , Acids/chemistry , Acids/pharmacology , Alanine/chemistry , Alanine/pharmacology , Crystallography, X-Ray , Enzyme Activation/drug effects , Humans , Inhibitory Concentration 50 , Models, Molecular , Molecular Structure , Protease Inhibitors/chemistry
10.
Sci Rep ; 1: 124, 2011.
Article in English | MEDLINE | ID: mdl-22355641

ABSTRACT

The success of Fc-fusion bio-therapeutics has spurred the development of other Fc-fusion products for treating and/or vaccinating against a range of diseases. We describe a method to modulate their function by converting them into well-defined stable polymers. This strategy resulted in cylindrical hexameric structures revealed by tapping mode atomic force microscopy (AFM). Polymeric Fc-fusions were significantly less immunogenic than their dimeric or monomeric counterparts, a result partly owing to their reduced ability to interact with critical Fc-receptors. However, in the absence of the fusion partner, polymeric IgG1-Fc molecules were capable of binding selectively to FcγRs, with significantly increased affinity owing to their increased valency, suggesting that these reagents may prove of immediate utility in the development of well-defined replacements for intravenous immunoglobulin (IVIG) therapy. Overall, these findings establish an effective IgG Fc-fusion based polymeric platform with which the therapeutic and vaccination applications of Fc-fusion immune-complexes can now be explored.


Subject(s)
Immunoglobulin Fc Fragments/metabolism , Animals , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Base Sequence , Biological Therapy , Complement System Proteins/metabolism , DNA Primers/genetics , Female , Histocompatibility Antigens Class I/metabolism , Humans , Immunization , Immunoglobulin Fc Fragments/chemistry , Immunoglobulin Fc Fragments/genetics , Immunoglobulin Fc Fragments/therapeutic use , Immunoglobulin G/chemistry , Immunoglobulin G/genetics , Immunoglobulin G/metabolism , Malaria/immunology , Malaria/parasitology , Malaria/therapy , Mice , Mice, Inbred BALB C , Models, Molecular , Plasmodium berghei , Protein Binding , Protein Multimerization , Receptors, Fc/metabolism , Receptors, IgG/metabolism , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/therapeutic use
11.
Bioorg Med Chem Lett ; 20(10): 3120-4, 2010 May 15.
Article in English | MEDLINE | ID: mdl-20443228

ABSTRACT

1H-Pyrazolo[4,3-d]pyrimidines are a class of potent and selective second generation phosphodiesterase 5 (PDE5) inhibitors. This work explores the potency, selectivity and efficacy of 1-(2-ethoxyethyl)-1H-pyrazolo[4,5-d]pyrimidines as PDE5 inhibitors resulting in the advancement of a clinical candidate.


Subject(s)
Enzyme Inhibitors/chemistry , Phosphodiesterase 5 Inhibitors , Pyrimidines/chemistry , Animals , Cyclic Nucleotide Phosphodiesterases, Type 5/metabolism , Dogs , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacokinetics , Humans , Microsomes, Liver/metabolism , Pyrimidines/chemical synthesis , Pyrimidines/pharmacokinetics , Structure-Activity Relationship
13.
Bioorg Med Chem Lett ; 19(15): 4088-91, 2009 Aug 01.
Article in English | MEDLINE | ID: mdl-19540112

ABSTRACT

A new class of potent and selective PDE5 inhibitors is disclosed. Guided by X-ray crystallographic data, optimization of an HTS lead led to the discovery of a series of 2-aryl, (N8)-alkyl substituted-6-aminosubstituted pyrido[3,2b]pyrazinones which show potent inhibition of the PDE5 enzyme. Synthetic details and some structure-activity relationships are also presented.


Subject(s)
Cyclic Nucleotide Phosphodiesterases, Type 5/chemistry , Phosphodiesterase 5 Inhibitors , Pyrazines/chemical synthesis , 3',5'-Cyclic-GMP Phosphodiesterases , Animals , Catalytic Domain , Chemistry, Pharmaceutical/methods , Crystallography, X-Ray/methods , Cyclic Nucleotide Phosphodiesterases, Type 6/antagonists & inhibitors , Cyclic Nucleotide Phosphodiesterases, Type 6/chemistry , Drug Design , Humans , Hydrogen-Ion Concentration , Inhibitory Concentration 50 , Phosphodiesterase Inhibitors/chemical synthesis , Phosphodiesterase Inhibitors/pharmacology , Phosphoric Diester Hydrolases/chemistry , Protein Structure, Tertiary , Pyrazines/pharmacology , Rats , Structure-Activity Relationship
14.
Curr Top Med Chem ; 7(4): 405-19, 2007.
Article in English | MEDLINE | ID: mdl-17305582

ABSTRACT

The clinical significance of phosphodiesterase 5 (PDE5) inhibition is increasingly understood following the pioneering work with sildenafil, and the continuing development programmes for both sildenafil and other marketed inhibitors. Since the initial launch of sildenafil for male erectile dysfunction (MED), approval has now been granted for treatment of pulmonary hypertension, whilst ongoing studies have indicated the potential of PDE5 inhibition for the treatment of a range of additional indications including cardioprotection, memory retention and diabetes. Many of these additional indications are best suited to chronic oral dosing and emphasise the need for highly selective inhibitors with extended duration of action. This article will focus on a research programme aimed at the discovery of improved second-generation PDE5 inhibitors. Essential features of these new PDE5 inhibitors would be enhanced selectivity across the whole PDE family and pharmacokinetics compatible with once daily dosing. Key elements used in this programme are high throughput screening (HTS), exploitation of co-crystal structural information for bound inhibitor in the PDE5 active site, and employment of parallel chemistry to speed progress. Under the guidance of co-crystal structural information, a non-selective HTS hit with poor physicochemistry was initially modified using parallel chemistry to give a lead compound (3) that established a new PDE5 inhibitor series. Notably, (3) displayed physicochemistry compatible with a long plasma half-life, and wide chemical scope. Subsequent optimisation of (3) using crystal structure information to guide design, led rapidly to highly potent and selective PDE5 inhibitors (47, 50). Continued focus on physical properties through ligand efficiency evaluation and lipophilicity (cLogP), maintained the inherently desirable physicochemistry of the initial lead.


Subject(s)
3',5'-Cyclic-GMP Phosphodiesterases/drug effects , Drug Design , Phosphodiesterase Inhibitors/pharmacology , Crystallography, X-Ray , Cyclic Nucleotide Phosphodiesterases, Type 5 , Molecular Structure , Phosphodiesterase Inhibitors/chemistry , Structure-Activity Relationship
15.
Health Phys ; 84(6): 737-46, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12822583

ABSTRACT

Lead is a hazardous material, and the U.S. Congress has mandated the rapid reduction of all hazardous waste generation as a matter of national policy. With the large amount of plutonium handling in numerous projects including the development of mixed oxide (MOX) fuel, 238Pu power sources, etc., hand glove protection for the emitted alpha, beta, and low energy photons is an important issue. Leaded gloves are the prime shields used for radiological hand protection. U.S. Department of Energy laboratories require a substitute material for the lead oxide in the gloves as a way to reduce mixed waste. To solve this problem, a new blend of non-hazardous materials that have the same radiological properties and approximately the same cost of production have been investigated. The investigations have produced alternative materials using calculations and experiments. The selection of the constituent compounds for the new composite materials was based on the k-absorption edge energy of the main constituent element(s) in the compounds. The formulations of these composites were fashioned on the principle of blending Neoprene rubber formulation with several constituent compounds. Calculations based on the Lambert-Beer attenuation law together with the mass attenuation coefficient values from the XCOM cross section database program were used to determine the transmission fractions of these proposed composite materials. Selected composite materials that compared favorably with the leaded-Neoprene were fabricated. These fabricated composite materials were tested with attenuation experiments and the results were in excellent agreement with the calculations using the Lambert-Beer attenuation law.


Subject(s)
Gloves, Protective , Manufactured Materials/radiation effects , Materials Testing/methods , Radiation Protection/instrumentation , Radiometry/methods , Computer-Aided Design , Equipment Design , Humans , Lead , Models, Chemical , Neoprene , Occupational Health , Plutonium , Radiation Dosage , Radiation Protection/methods , Scattering, Radiation
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