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Edwards T, Williams C, Teethaisong Y, Sealey J, Sasaki S, Hobbs G, Cuevas LE, Evans K, Adams ER. A highly multiplexed melt-curve assay for detecting the most prevalent carbapenemase, ESBL, and AmpC genes. Diagn Microbiol Infect Dis 2020; 97:115076. [PMID: 32521424 DOI: 10.1016/j.diagmicrobio.2020.115076] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 05/01/2020] [Accepted: 05/03/2020] [Indexed: 01/12/2023]
Abstract
Resistance to third-generation cephalosporins and carbapenems in Gram-negative bacteria is chiefly mediated by beta-lactamases including extended-spectrum beta-lactamase (ESBL), AmpC, and carbapenemase enzymes. Routine phenotypic detection methods do not provide timely results, and there is a lack of comprehensive molecular panels covering all important markers. An ESBL/carbapenemase high-resolution melt analysis (HRM) assay (SHV, TEM, CTX-M ESBL families, and NDM, IMP, KPC, VIM and OXA-48-like carbapenemases) and an AmpC HRM assay (16S rDNA control, FOX, MOX, ACC, EBC, CIT, and DHA) were designed and evaluated on 111 Gram-negative isolates with mixed resistance patterns. The sensitivity for carbapenemase, ESBL, and AmpC genes was 96.7% (95% confidence interval [CI]: 82.8-99.9%), 93.6% (95% CI: 85.7-97.9%), and 93.8% (95% CI: 82.8-98.7%), respectively, with a specificity of 100% (95% CI: 95.6-100%), 93.9% (95% CI: 79.8-99.3%), and 93.7% (95% CI: 84.5-98.2%). The HRM assays enable the simultaneous detection of the 14 most important ESBL, carbapenemase, and AmpC genes and could be used as a molecular surveillance tool or to hasten detection of antimicrobial resistance for treatment management.
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Affiliation(s)
- T Edwards
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.
| | - C Williams
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Y Teethaisong
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - J Sealey
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - S Sasaki
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - G Hobbs
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - L E Cuevas
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - K Evans
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - E R Adams
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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2
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Isgren CM, Edwards T, Pinchbeck GL, Winward E, Adams ER, Norton P, Timofte D, Maddox TW, Clegg PD, Williams NJ. Emergence of carriage of CTX-M-15 in faecal Escherichia coli in horses at an equine hospital in the UK; increasing prevalence over a decade (2008-2017). BMC Vet Res 2019; 15:268. [PMID: 31357996 PMCID: PMC6664770 DOI: 10.1186/s12917-019-2011-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 07/16/2019] [Indexed: 11/23/2022] Open
Abstract
Background This study investigated changes over time in the epidemiology of extended-spectrum β-lactamase (ESBL) producing Escherichia coli within a single equine referral hospital in the UK. Faecal samples were collected from hospitalised horses in 2008 and 2017, processed using selective media and standard susceptibility laboratory methods. A novel real-time PCR with high resolution melt analysis was used to distinguish blaCTX-M-1 and blaCTX-M-15 within CTX-M-1 group. Results In 2008, 457 faecal samples from 103 horses were collected, with ESBL-producing E. coli identified in 131 samples (28.7, 95% CI 24.6–33.1). In 2017, 314 faecal samples were collected from 74 horses with ESBL-producing E. coli identified in 157 samples (50.0, 95% CI 44.5–55.5). There were 135 and 187 non-duplicate ESBL-producing isolates from 2008 and 2017, respectively. In 2008, 12.6% of isolates belonged to CTX-M-1 group, all carrying blaCTX-M-1, whilst in 2017, 94.1% of isolates were CTX-M-1 group positive and of these 39.2 and 60.8% of isolates carried blaCTX-M-1 and blaCTX-M-15, respectively. In addition, the prevalence of doxycycline, gentamicin and 3rd generation cephalosporin resistance increased significantly from 2008 to 2017 while a decreased prevalence of phenotypic resistance to potentiated sulphonamides was observed. Conclusions The real-time PCR proved a reliable and high throughput method to distinguish between blaCTX-M-1 and blaCTX-M-15. Furthermore, its use in this study demonstrated the emergence of faecal carriage of CTX-M-15 in hospitalised horses, with an increase in prevalence of ESBL-producing E. coli as well as increased antimicrobial resistance to frequently used antimicrobials.
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Affiliation(s)
- C M Isgren
- Institute of Infection and Global Health, University of Liverpool, Neston, England.
| | - T Edwards
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, England
| | - G L Pinchbeck
- Institute of Infection and Global Health, University of Liverpool, Neston, England
| | - E Winward
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, England
| | - E R Adams
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, England
| | - P Norton
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, England
| | - D Timofte
- Institute of Infection and Global Health, University of Liverpool, Neston, England.,Institute of Veterinary Science, University of Liverpool, Neston, England
| | - T W Maddox
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, England
| | - P D Clegg
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, England
| | - N J Williams
- Institute of Infection and Global Health, University of Liverpool, Neston, England
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3
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Santos VS, Goletti D, Kontogianni K, Adams ER, Molina-Moya B, Dominguez J, Crudu V, Martins-Filho PRS, Ruhwald M, Lawson L, Bimba JS, Garcia-Basteiro AL, Petrone L, Kabeer BS, Reither K, Cuevas LE. Acute phase proteins and IP-10 as triage tests for the diagnosis of tuberculosis: systematic review and meta-analysis. Clin Microbiol Infect 2018; 25:169-177. [PMID: 30076971 DOI: 10.1016/j.cmi.2018.07.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/26/2018] [Accepted: 07/18/2018] [Indexed: 01/23/2023]
Abstract
OBJECTIVES We examined the data reported in studies for diagnostic purposes and to discuss whether their intended use could be extended to triage, as rule-in or rule-out tests to select individuals who should undergo further confirmatory tests. METHODS We searched Scopus, PubMed and Web of Science with the terms 'acute phase proteins,' 'IP-10,' 'tuberculosis,' 'screening' and 'diagnosis,' extracted the sensitivity and specificity of the biomarkers and explored methodologic differences to explain performance variations. Summary estimates were calculated using random-effects models for overall pooled accuracy. The hierarchical summary receiver operating characteristic model was used for meta-analysis. RESULTS We identified 14, four and one studies for C-reactive protein (CRP), interferon γ-induced protein 10 (IP-10) and alpha-1-acid glycoprotein (AGP). The pooled CRP sensitivity/specificity (95% confidence interval) was 89% (80-96) and 57% (36-65). Sensitivity/specificity were higher in high-tuberculosis-burden countries (90%/64%), HIV-infected individuals (91%/61%) and community-based studies (90%/62%). IP-10 sensitivity/specificity in TB vs. non-TB studies was 85%/63% and in TB and HIV coinfected vs. other lung conditions 94%/21%. However, IP-10 studies included diverse populations and a high risk of bias, resulting in very low-quality evidence. AGP had 86%/93% sensitivity/specificity. CONCLUSIONS Few studies have evaluated CRP, IP-10 and AGP for the triage of symptomatic patients. Their high sensitivity and moderate specificity warrant further prospective studies exploring whether their combined use could optimize performance.
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Affiliation(s)
- V S Santos
- Centre for Epidemiology and Public Health, Federal University of Alagoas, Arapiraca, Brazil
| | - D Goletti
- Department of Clinical and Clinical Research, 'L. Spallanzani' National Institute for Infectious Diseases (INMI), IRCCS, Rome, Italy
| | - K Kontogianni
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - E R Adams
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - B Molina-Moya
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d'Investigació Germans Trias i Pujol, Universitat Autònoma de Barcelona, Carretera del Canyet s/n, 08916, Badalona, Spain
| | - J Dominguez
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d'Investigació Germans Trias i Pujol, Universitat Autònoma de Barcelona, Carretera del Canyet s/n, 08916, Badalona, Spain
| | - V Crudu
- National TB Reference Laboratory, Phthisiopneumology Institute 'Chiril Draganiuc,' Chişinău, Republic of Moldova
| | - P R S Martins-Filho
- Investigative Pathology Laboratory, Federal University of Sergipe, Aracaju, Brazil
| | - M Ruhwald
- Center for Vaccine Research, Statens Serum Institut, Copenhagen, Denmark
| | - L Lawson
- Zankli Research Laboratory, Bingham University, Nassarawa State, Nigeria
| | - J S Bimba
- Zankli Research Laboratory, Bingham University, Nassarawa State, Nigeria
| | - A L Garcia-Basteiro
- Centro de Investigação em Saude de Manhiça (CISM), Rua 12, Cambeve CP 1929, Maputo, Mozambique; Amsterdam Institute for Global Health (AIGHD), Amsterdam, The Netherlands; Barcelona Institute for Global Health (ISGLobal), Barcelona, Spain
| | - L Petrone
- Department of Clinical and Clinical Research, 'L. Spallanzani' National Institute for Infectious Diseases (INMI), IRCCS, Rome, Italy
| | - B S Kabeer
- Department of Clinical and Clinical Research, 'L. Spallanzani' National Institute for Infectious Diseases (INMI), IRCCS, Rome, Italy
| | - K Reither
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - L E Cuevas
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom.
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van den Bogaart E, de Bes HM, Balraadjsing PPS, Mens PF, Adams ER, Grobusch MP, van Die I, Schallig HDFH. Leishmania donovani infection drives the priming of human monocyte-derived dendritic cells during Plasmodium falciparum co-infections. Parasite Immunol 2015; 37:453-69. [PMID: 26173941 DOI: 10.1111/pim.12214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/07/2015] [Indexed: 11/28/2022]
Abstract
Functional impairment of dendritic cells (DCs) is part of a survival strategy evolved by Leishmania and Plasmodium parasites to evade host immune responses. Here, the effects of co-exposing human monocyte-derived DCs to Leishmania donovani promastigotes and Plasmodium falciparum-infected erythrocytes were investigated. Co-stimulation resulted in a dual, dose-dependent effect on DC differentiation which ranged from semi-mature cells, secreting low interleukin(-12p70 levels to a complete lack of phenotypic maturation in the presence of high parasite amounts. The effect was mainly triggered by the Leishmania parasites, as illustrated by their ability to induce semi-mature, interleukin-10-producing DCs, that poorly responded to lipopolysaccharide stimulation. Conversely, P. falciparum blood-stage forms failed to activate DCs and only slightly interfered with lipopolysaccharide effects. Stimulation with high L. donovani concentrations triggered phosphatidylserine translocation, whose onset presented after initiating the maturation impairment process. When added in combination, the two parasites could co-localize in the same DCs, confirming that the leading effects of Leishmania over Plasmodium may not be due to mutual exclusion. Altogether, these results suggest that in the presence of visceral leishmaniasis-malaria co-infections, Leishmania-driven effects may overrule the more silent response elicited by P. falciparum, shaping host immunity towards a regulatory pattern and possibly delaying disease resolution.
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Affiliation(s)
- E van den Bogaart
- Parasitology Unit, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, the Netherlands
| | - H M de Bes
- Parasitology Unit, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, the Netherlands
| | - P P S Balraadjsing
- Parasitology Unit, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, the Netherlands
| | - P F Mens
- Parasitology Unit, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, the Netherlands.,Division of Internal Medicine, Department of Infectious Diseases, Center of Tropical Medicine and Travel Medicine, Academic Medical Center, Amsterdam, the Netherlands
| | - E R Adams
- Parasitology Unit, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, the Netherlands
| | - M P Grobusch
- Division of Internal Medicine, Department of Infectious Diseases, Center of Tropical Medicine and Travel Medicine, Academic Medical Center, Amsterdam, the Netherlands
| | - I van Die
- Department of Molecular Cell Biology, VU University Medical Centre (VUMC), Amsterdam, the Netherlands
| | - H D F H Schallig
- Parasitology Unit, Department of Biomedical Research, Royal Tropical Institute (KIT), Amsterdam, the Netherlands
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5
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Mans DRA, Kent AD, Hu RV, Lai A. Fat EJ, Schoone GJ, Adams ER, Rood EJ, Alba S, Sabajo LOA, Lai A Fat RF, de Vries HJC, Schallig HDFH. Monitoring the response of patients with cutaneous leishmaniasis to treatment with pentamidine isethionate by quantitative real-time PCR, and identification ofLeishmaniaparasites not responding to therapy. Clin Exp Dermatol 2015; 41:610-5. [DOI: 10.1111/ced.12786] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2015] [Indexed: 11/29/2022]
Affiliation(s)
- D. R. A. Mans
- Anton de Kom University of Suriname; Paramaribo Suriname
| | - A. D. Kent
- Anton de Kom University of Suriname; Paramaribo Suriname
| | - R. V. Hu
- Dermatological Service; Ministry of Health; Paramaribo Suriname
| | - E. J. Lai A. Fat
- Department of Dermatology; Academic Hospital Paramaribo; Paramaribo Suriname
| | | | - E. R. Adams
- Royal Tropical Institute; Amsterdam The Netherlands
| | - E. J. Rood
- Royal Tropical Institute; Amsterdam The Netherlands
| | - S. Alba
- Royal Tropical Institute; Amsterdam The Netherlands
| | - L. O. A. Sabajo
- Dermatological Service; Ministry of Health; Paramaribo Suriname
| | - R. F. Lai A Fat
- Department of Dermatology; Academic Hospital Paramaribo; Paramaribo Suriname
| | - H. J. C. de Vries
- Department of Dermatology; Academic Medical Center; Amsterdam The Netherlands
- Center for Infection and Immunology Amsterdam (CINIMA); University of Amsterdam; Amsterdam The Netherlands
- STI Outpatient Clinic; Public Health Service of Amsterdam (GGD Amsterdam); Amsterdam The Netherlands
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6
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Adams ER. Molecular Diagnostics - Current Research and Applications. Clin Infect Dis 2015. [DOI: 10.1093/cid/civ218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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7
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Chaouch M, Adams ER, Driss M, Ben Abderrazak S. LATENT CLASS ANALYSIS IN DIAGNOSTIC TESTS EVALUATION FOR CANINE LEISHMANIA INFANTUM INFECTION. Arch Inst Pasteur Tunis 2014; 91:51-55. [PMID: 26402970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Accurate assessment of diagnostic tests may be biased if an imperfect reference test is used for comparison; such a situation exists for the diagnosis of canine leishmaniasis. We compared classical diagnostic tests for Leishmania infantum with Latent Class Analysis (LCA), to assess whether we could make a more accurate calculation of diagnostic accuracy. Microscopy (Lymph node aspirate), serological test (IFAT), and molecular tests (LAMP and PCR) data were recorded for 75 dogs captured in Tunisian endemic area and suspected of leishmaniasis. Sensitivity and specificity estimates with the 2 x 2 contingency tables (Microscopy as gold standard) were broadly corroborated by LCA. However, the LCA provided a way to control the study limitations (small sample size) as well as for confounding factors. It also produces consistent estimates of the test characteristics. LCA estimation of the sensitivity and specifcity of the LAMP cpb assay (se: 68.7% [95% CI 573-80%] and sp: 86.2 [95% CI 749-975%]) is higher as compared to classical calculations (se: 54.2% [95% CI 38.2-69.5%] and sp: 80% [95% CI 65.2-89.5%). Considering the lack of an adequate reference standard, LCA proved to be a useful tool to independently evaluate diagnostic methods.
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8
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Affiliation(s)
- L. H. Ginn
- USDA-ARS Soybean Res. Unit; P.O. Box 343 Stoneville MS 38776
| | - L. G. Heatherly
- USDA-ARS Soybean Res. Unit; P.O. Box 343 Stoneville MS 38776
| | - E. R. Adams
- USDA-ARS Applic. and Prod. Technol. Res. Unit; P.O. Box 36 Stoneville MS 38776
| | - R. A. Wesley
- USDA-ARS Applic. and Prod. Technol. Res. Unit; P.O. Box 36 Stoneville MS 38776
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Abstract
Trypanosomes are the causative agents of many diseases of medical and veterinary importance, including sleeping sickness and nagana in Africa, and Chagas disease in South America. Accurate identification of trypanosome species is essential, as some species are morphologically indistinguishable, yet differ greatly in their pathogenicity. A range of molecular tools has been developed for identification of species and strains of trypanosomes. PCR, using primer sets designed to amplify a specific DNA fragment from each trypanosome species, is frequently used. More recently, generic systems have been developed that can potentially recognize all trypanosome species, such as amplification of the internal transcribed spacer and fluorescent fragment length barcoding, both of which use interspecies size variation in PCR fragments amplified from the ribosomal RNA locus. Loop-mediated isothermal amplification is a promising technique and is able to detect trypanosomes in blood, serum and cerebrospinal fluid. The advantages of these techniques for high-throughput and sensitive molecular identification will be discussed.
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Affiliation(s)
- E R Adams
- School of Biological Sciences, University of Bristol, Bristol, BS8 1UG, UK.
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10
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Hamilton PB, Adams ER, Malele II, Gibson WC. A novel, high-throughput technique for species identification reveals a new species of tsetse-transmitted trypanosome related to the Trypanosoma brucei subgenus, Trypanozoon. Infect Genet Evol 2007; 8:26-33. [PMID: 17964224 DOI: 10.1016/j.meegid.2007.09.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 09/07/2007] [Accepted: 09/12/2007] [Indexed: 11/26/2022]
Abstract
We describe a novel method of species identification, fluorescent fragment length barcoding, based on length variation in regions of the 18S and 28Salpha ribosomal DNA. Fluorescently tagged primers, designed in conserved regions of the 18S and 28Salpha ribosomal DNA, were used to amplify fragments with inter-species size variation, and sizes determined accurately using an automated DNA sequencer. By using multiple regions and different fluorochromes, a barcode unique to each species was generated. The technique was developed for the identification of African tsetse-transmitted trypanosomes and validated using DNA from laboratory isolates representing known species, subspecies and subgroups. To test the methodology, we examined 91 trypanosome samples from infected tsetse fly midguts from Tanzania, most of which had already been identified by species-specific and generic PCR tests. Identifications were mainly in agreement, but the presence of an unknown trypanosome in several samples was revealed by its unique barcode. Phylogenetic analyses based on 18S rDNA and glycosomal glyceraldehyde phosphate dehydrogenase gene sequences confirmed that this trypanosome is a new species and it is within the Trypanosoma brucei clade, as a sister group of subgenus Trypanozoon. The overall identification rate of trypanosome-infected midgut samples increased from 78 to 96% using FFLB instead of currently available PCR tests. This was due to the high sensitivity of FFLB as well as its capacity to identify previously unrecognised species. FFLB also allowed the identification of multiple species in mixed infections. The method enabled high-throughput and accurate species identification and should be applicable to any group of organisms where there is length variation in regions of rDNA.
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Affiliation(s)
- P B Hamilton
- School of Biosciences, University of Exeter, Exeter EX4 4PS, UK.
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11
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Adams ER, Hamilton PB, Malele II, Gibson WC. The identification, diversity and prevalence of trypanosomes in field caught tsetse in Tanzania using ITS-1 primers and fluorescent fragment length barcoding. Infect Genet Evol 2007; 8:439-44. [PMID: 17826361 DOI: 10.1016/j.meegid.2007.07.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2007] [Revised: 07/26/2007] [Accepted: 07/30/2007] [Indexed: 10/23/2022]
Abstract
We report on the development of two generic, PCR-based methods, which replace the multiple species-specific PCR tests used previously to identify the trypanosome species carried by individual tsetse flies. The first method is based on interspecies size variation in the PCR product of the ITS-1 region of the ribosomal RNA (rRNA) locus. In the second approach, length variation of multiple fragments within the 18S and 28S rRNA genes is assayed by PCR amplification with fluorescent primers; products are subsequently sized accurately and rapidly by the use of an automated DNA sequencer. Both methods were used to identify samples collected during large-scale field studies of trypanosome-infected tsetse in Tanzania in the National Parks of Tarangire and Serengeti, and the coastal forest reserve of Msubugwe. The fluctuations of trypanosome prevalence over time and two different field seasons are discussed. As well as facilitating the identification of trypanosome species with increased speed, precision and sensitivity, these generic systems have enabled us to identify two new species of trypanosome.
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Affiliation(s)
- E R Adams
- School of Biological Sciences, University of Bristol, Bristol BS8 1UG, UK.
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12
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Adams ER, Malele II, Msangi AR, Gibson WC. Trypanosome identification in wild tsetse populations in Tanzania using generic primers to amplify the ribosomal RNA ITS-1 region. Acta Trop 2006; 100:103-9. [PMID: 17109808 DOI: 10.1016/j.actatropica.2006.10.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2006] [Revised: 09/25/2006] [Accepted: 10/04/2006] [Indexed: 10/23/2022]
Abstract
Tsetse flies transmit many species of trypanosomes in Africa, some of which are human and livestock pathogens of major medical and socio-economic impact. Identification of trypanosomes is essential to assess the disease risk posed by particular tsetse populations. We have developed a single generic PCR test to replace the multiple species-specific PCR tests used previously to identify the trypanosome species carried by individual tsetse flies. In the generic PCR test, inter-species size variation in the PCR product of the internal transcribed spacer (ITS-1) region of the ribosomal RNA repeat region enables species identification. The test was applied to identify trypanosomes in midgut samples stored on FTA cards from wild-caught flies in two regions of Tanzania. Identifications were verified by sequencing the amplified ITS-1 region and/or species-specific PCR tests. The method facilitated the identification of large numbers of field samples quickly and accurately. Whereas species-specific tests are incapable of recognising previously unknown species, the generic test enabled a new species to be identified by the unique size of the amplified product. Thus, even without access to any isolate of this new species, we could collect data on its distribution, prevalence and co-occurrence with other trypanosomes. The combined molecular and ecological profiles should facilitate the isolation and full biological characterization of this species in the future.
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Affiliation(s)
- E R Adams
- School of Biological Sciences, University of Bristol, Bristol, UK
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13
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Gulbis AAS, Elliot JL, Person MJ, Adams ER, Babcock BA, Emilio M, Gangestad JW, Kern SD, Kramer EA, Osip DJ, Pasachoff JM, Souza SP, Tuvikene T. Charon's radius and atmospheric constraints from observations of a stellar occultation. Nature 2006; 439:48-51. [PMID: 16397492 DOI: 10.1038/nature04276] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Accepted: 09/21/2005] [Indexed: 11/08/2022]
Abstract
The physical characteristics of Pluto and its moon, Charon, provide insight into the evolution of the outer Solar System. Although previous measurements have constrained the masses of these bodies, their radii and densities have remained uncertain. The observation of a stellar occultation by Charon in 1980 established a lower limit on its radius of 600 km (ref. 3) (later refined to 601.5 km; ref. 4) and suggested a possible atmosphere. Subsequent, mutual event modelling yielded a range of 600-650 km (ref. 5), corresponding to a density of 1.56 +/- 0.22 g cm(-3) (refs 2, 5). Here we report multiple-station observations of a stellar occultation by Charon. From these data, we find a mean radius of 606 +/- 8 km, a bulk density of 1.72 +/- 0.15 g cm(-3), and rock-mass fraction 0.63 +/- 0.05. We do not detect a significant atmosphere and place 3sigma upper limits on atmospheric number densities for candidate gases. These results seem to be consistent with collisional formation for the Pluto-Charon system in which the precursor objects may have been differentiated, and they leave open the possibility of atmospheric retention by the largest objects in the outer Solar System.
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Affiliation(s)
- A A S Gulbis
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA.
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Adams ER, Leffert JJ, Craig DJ, Spector T, Pizzorno G. In vivo effect of 5-ethynyluracil on 5-fluorouracil metabolism determined by 19F nuclear magnetic resonance spectroscopy. Cancer Res 1999; 59:122-7. [PMID: 9892196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Biochemical modulation of 5-fluorouracil (5-FU) has been used over the past 20 years to improve the therapeutic efficacy of this antineoplastic agent. Recently, modulation of the catabolic pathway of this fluoropyrimidine has been the focus of extensive preclinical and clinical investigation. Dihydropyrimidine dehydrogenase catalyzes the rate-limiting step in the catabolism of 5-FU and rapidly degrades 60-90% of the drug. An irreversible inactivating inhibitor of this enzyme, 5-ethynyluracil (EU), markedly improves the antitumor effect of 5-FU in animal models. Early clinical studies have shown a substantial alteration of the systemic disposition of 5-FU with an increase in 5-FU terminal half-life and have also indicated that EU allows safe oral administration of 5-FU by improving the oral bioavailability of the fluoropyrimidine, which is otherwise too erratic and unpredictable for a drug with such a limited therapeutic window. We evaluated the effect of EU on the metabolism of 5-FU in mice bearing colon 38 tumors using 19F nuclear magnetic resonance spectroscopy. Ex vivo measurements of tissue extracts from liver, kidney, and tumor indicated a >95% elimination of alpha-fluoro-beta-ureidopropionic acid and a-fluoro-beta-alanine signals in the tissues of mice that received 2 mg/kg of EU before administration of 5-FU. The spectra also showed an increased formation of fluoronucleotides in both normal and tumor tissues, a prolonged presence of 5-FU, and the accumulation of 5-fluorouridine that otherwise is undetectable, particularly in normal tissues. The in vivo NMR experiments on colon 38 tumors confirmed these findings, showing a complete elimination of the a-fluoro-beta-ureidopropionic acid and a-fluoro-beta-alanine signals in tumors treated with EU and a dramatic formation and accumulation of 5-fluorouridine mono-, di-, and triphosphates and 5-fluorouridine. Thus, by inactivating dihydropyrimidine dehydrogenase, EU prolonged the half-life for 5-FU, almost completely eliminated its catabolism for 4-6 h, which led to an increased accumulation of 5-fluorouridine mono-, di-, and triphosphates in both normal and tumor tissues.
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Affiliation(s)
- E R Adams
- Yale University School of Medicine, Department of Internal Medicine, New Haven, Connecticut 06520, USA
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Holland SK, Bergman AM, Zhao Y, Adams ER, Pizzorno G. 19F NMR monitoring of in vivo tumor metabolism after biochemical modulation of 5-fluorouracil by the uridine phosphorylase inhibitor 5-benzylacyclouridine. Magn Reson Med 1997; 38:907-16. [PMID: 9402191 DOI: 10.1002/mrm.1910380609] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A uridine phosphorylase inhibitor, 5-benzylacyclouridine (BAU), has been utilized as biochemical modulator of 5-fluorouracil (5-FU) anti-tumor activity in a murine tumor model. The effect of BAU on 5-FU metabolism has been evaluated using in vitro and in vivo 19F NMR spectroscopy. The analysis of the NMR data revealed an increased formation and retention of fluorouracil nucleotides and fluorouridine in colon 38 tumors treated with the regimen containing BAU and a reduction in 5-FU catabolites (alpha-fluoro-beta-ureidopropionic acid and alpha-fluoro-beta-alanine). In the normal tissues evaluated, the presence of BAU did not significantly alter the metabolism and presence of fluoropyrimidine species, indicating a more selective effect on tumor tissues. Therapy experiments on C57/BL6 mice bearing colon 38 tumor showed that the administration of 120 mg/kg BAU 30 min before 5-FU at 85 mg/kg, on a weekly basis, resulted in an increased antineoplastic effect compared to the same dose of 5-FU alone. A smaller dose of 5-FU (60 mg/kg) also administered 30 min after 120 mg/kg BAU caused a reduction in tumor growth similar to 5-FU alone. The addition of BAU to 5-FU (85 mg/kg) resulted in a slight increase, although statistically nonsignificant, in host toxicity without causing any toxic death during the chemotherapeutic treatment. 19F NMR spectroscopy is here shown to be a powerful technique to evaluate changes in the metabolism of fluoropyrimidines after the use of biochemical modulator and to allow a correlation between improved therapeutic response with the biochemical effects generated in tissues.
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Affiliation(s)
- S K Holland
- Department of Radiology, Children's Hospital Medical Center, University of Cincinnati, Ohio, USA
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16
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Adams ER, Dratz EA, Gizachew D, Deleo FR, Yu L, Volpp BD, Vlases M, Jesaitis AJ, Quinn MT. Interaction of human neutrophil flavocytochrome b with cytosolic proteins: transferred-NOESY NMR studies of a gp91phox C-terminal peptide bound to p47phox. Biochem J 1997; 325 ( Pt 1):249-57. [PMID: 9224653 PMCID: PMC1218552 DOI: 10.1042/bj3250249] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
During activation of the neutrophil NADPH oxidase, cytosolic p47(phox) is translocated to the membrane where it associates with flavocytochrome b via multiple binding regions, including a site in the C-terminus of gp91(phox). To investigate this binding site further, we studied the three-dimensional structure of a gp91(phox) C-terminal peptide (551SNSESGPRGVHFIFNKEN568) bound to p47(phox) using transferred nuclear Overhauser effect spectroscopy (Tr-NOESY) NMR. Using MARDIGRAS analysis and simulated annealing, five similar sets of structures of the p47(phox)-bound peptide were obtained, all containing an extended open bend from Ser5 to Phe14 (corresponding to gp91(phox) residues 555-564). The ends of the peptide were poorly defined, however, suggesting they were more flexible. Therefore further refinement was performed on the Ser5-Phe14 region of the peptide after omitting the ends of the peptide from consideration. In this case, two similar structures were obtained. Both structures again exhibited extended open-bend conformations. In addition, the amino acid side chains that showed evidence of immobilization on binding to p47(phox) correlated directly with those that were found previously to be essential for biological activity. Thus during NADPH oxidase assembly, the C-terminus of gp91(phox) binds to 47(phox) in an extended conformation between gp91(phox) residues 555 and 564, with immobilization of all of the amino acid side chains in the 558RGVHFIF564 region except for His561.
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Affiliation(s)
- E R Adams
- Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT59717, USA
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17
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Francis PC, Carlson KH, Owen NV, Adams ER. Preclinical toxicology studies with the new dopamine agonist pergolide. Acute, subchronic, and chronic evaluations. Arzneimittelforschung 1994; 44:278-84. [PMID: 8192691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Pergolide (LY127809, CAS 66104-23-2), a dopamine agonist for the treatment of Parkinson's disease, was evaluated for toxicity in acute, subchronic, and chronic studies. Acute toxicity tests using oral, intravenous and intraperitoneal routes were conducted in rats, mice, rabbits, and dogs. The acute oral median lethal doses (MLD) ranged from 8.4 to 33.6 mg/kg in Wistar and Fischer 344 rats, and from 54.0 to 87.2 mg/kg in ICR mice. Oral doses of 20 and 25 mg/kg produced no mortality in rabbits or dogs, respectively. The MLD by the iv route ranged from 0.59 to 0.87 mg/kg for Fischer 344 rats and from 11.6 to 37.1 mg/kg for ICR mice. The predominant signs of toxicity in the acute studies included hyperactivity, poor grooming, ptosis, aggressive behavior, increased gnawing activity, tremors, convulsions, and emesis. In the subchronic and chronic studies, Fischer 344 rats, B6C3F1 mice, and beagle dogs were administered pergolide either by gavage or in the diet for up to 1 year. Daily doses in these studies ranged up to 20 mg/kg for rats, 45 mg/kg for mice, and 5 mg/kg for dogs. The predominant treatment-related effects seen in these studies were attributable to the pharmacologic activity of pergolide. These consisted primarily of CNS-mediated clinical signs in rats and dogs, weight loss or decreased weight gain, emesis in dogs, and inhibition of lysis of corpora lutea with a corresponding increase in the weight of the uterus and ovaries. Pergolide treatment was not associated with any specific target organ toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P C Francis
- Toxicology Research Laboratories, Eli Lilly and Company, Greenfield, Indiana
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Bendele RA, Adams ER, Hoffman WP, Gries CL, Morton DM. Carcinogenicity studies of fluoxetine hydrochloride in rats and mice. Cancer Res 1992; 52:6931-5. [PMID: 1458482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The antidepressant drug fluoxetine HCl was tested for carcinogenicity in three well designed and controlled studies in Fischer rats and C57BL/6 x C3H F1 mice. The compound was administered to the animals for 24 months at dietary doses of approximately 0, 0.5, 2.0, or 10.0 mg/kg body weight in rats and 1.0, 5.0, or 10.0 mg/kg in mice. The highest dose tested was a maximum tolerated dose for both species as evidenced by clinical signs (rats and mice) and some mortality (mice) referable to central nervous system pharmacological effects, decreased weight gain (rats), and histopathological changes of phospholipidosis (rats) and hepatic fatty change (mice). There was no evidence of an increased incidence of any type of unusual or commonly occurring spontaneous neoplasm in either rats or mice. There were statistically significant decreases in a few commonly occurring neoplasms. The data reported herein provide convincing evidence that fluoxetine is neither a complete carcinogen nor a tumor promoter.
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Affiliation(s)
- R A Bendele
- Toxicology Research Laboratories, Division of Eli Lilly and Company, Greenfield, Indiana 46140
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19
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Abstract
B6C3F1 mice were maintained for 24 months on diets containing 0, 563, 2250 or 4500 ppm trifluralin. These dietary concentrations corresponded to daily doses of approximately 70, 285 or 570 mg/kg body weight, respectively. The control group contained 120 mice/sex and treated groups consisted of 80 mice/sex. There were no treatment-related effects on the survival, appearance or behaviour of the mice. Survival at test termination was at least 67% in each group. Compared with controls, mean body weight was significantly reduced in a dose-related manner in mice of both sexes given the 2250 and 4500 ppm diets. At 21 months, the reduction in body weight was greater than or equal to 15 and greater than or equal to 30%, respectively. At study termination, dose-related decreases in erythrocytic and leucocytic values were also observed at dietary levels of 2250 and 4500 ppm. In clinical chemistry evaluations, blood urea nitrogen levels and alkaline phosphatase activity in mice of both sexes were significantly increased at trifluralin levels of 2250 and 4500 ppm. Blood urea nitrogen also showed a marginal increase in females given the low dose of trifluralin. Alanine aminotransferase activity was significantly increased in males at all treatment levels. Although there were a number of absolute and relative organ weight changes in all three treatment groups that were significantly different from the control values, the reduced relative kidney weights in males and the increased relative liver weights in both sexes at dietary levels of 2250 and 4500 ppm were the only changes that could be correlated with altered clinical chemistry values.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P C Francis
- Toxicology Research Laboratories, Lilly Research Laboratories, Division of Eli Lilly and Company, Greenfield, IN 46140
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Garriott ML, Adams ER, Probst GS, Emmerson JL, Oberly TJ, Kindig DE, Neal SB, Bewsey BJ, Rexroat MA. Genotoxicity studies on the preemergence herbicide trifluralin. Mutat Res 1991; 260:187-93. [PMID: 2046699 DOI: 10.1016/0165-1218(91)90007-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- M L Garriott
- Toxicology Division, Eli Lilly and Company, Greenfield, IN 46140
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Probst KS, Higdon GL, Fisher LF, McGrath JP, Adams ER, Emmerson JL. Preclinical toxicology studies with nizatidine, a new H2-receptor antagonist: acute, subchronic, and chronic toxicity evaluations. Fundam Appl Toxicol 1989; 13:778-92. [PMID: 2576009 DOI: 10.1016/0272-0590(89)90333-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Nizatidine (NIZ), a new antiulcer drug, was evaluated for toxicity in acute, subchronic, and chronic tests. Acute toxicity studies were conducted in rats, mice, dogs, and monkeys. Median lethal doses (MLD) in rodents were greater than 1600, 230, and 1000 mg/kg by oral (po), iv, and sc administration, respectively. No deaths occurred in dogs given single doses of 800 mg/kg (po), 75 mg/kg (iv), or 225 mg/kg (im) or in monkeys given 1200 mg/kg (po) or 200 mg/kg (iv). Rats survived up to 1.0% dietary NIZ (daily intake ranging from 24 to 800 mg/kg/day) for 1 year. Slight decreases in body weight gain and increases in liver and kidney weights occurred. Slight decreases in erythrocytic parameters at 3 months were not present at 6 or 12 months. Mice survived up to 1.5% dietary NIZ for 3 months and effects were limited to slight decreases in body weight gain and increases in relative liver weight. Dogs survived oral doses up to 800 mg/kg/day for 3 months but had numerous clinical signs of toxicity and body weight loss. All dogs given oral NIZ doses up to 400 mg/kg/day survived except for one high-dose dog that was killed in a moribund condition following convulsions in the 41st week of treatment. Effects in dogs included miosis, body weight loss, increased thrombocyte counts, and decreased hepatic microsomal enzyme activity and P450 content. The increase in thrombocyte counts was unaccompanied by changes in thrombocyte function and did not reoccur in a subsequent study. A decrease in plasma testosterone in two of three surviving male dogs given 400 mg/kg/day for 1 year was unaccompanied by effects on the size or morphology of testes or prostate. Peak plasma levels of NIZ in all species tested were in excess of human plasma levels after therapeutic doses. In conclusion, there was no evidence of significant toxicity in organs or tissues including those sites (gastric mucosa, male sex organs, and liver) that have been affected by some agents of this therapeutic class.
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Affiliation(s)
- K S Probst
- Toxicology Division, Lilly Research Laboratories, Eli Lilly and Company, Greenfield, Indiana 46140
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Dill K, Adams ER, Davis SD, O'Connor RJ, McGown EL, Hallowell SF. Reaction of trans-2-chlorovinylarsine oxide with polydeoxynucleotides. Drug Chem Toxicol 1989; 12:337-43. [PMID: 2561097 DOI: 10.3109/01480548908999163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Trans-2-chlorovinylarsine oxide (in DCl/acetone-d6) was added to various polydeoxynucleotides. The arsenical did react with poly[dG].poly[dC], releasing guanine, and resulting in a partial apurinic duplex.
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Affiliation(s)
- K Dill
- Department of Chemistry, Clemson University, SC 29634-1905
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Abstract
The lipoic acid-phenyldichloroarsine adduct was prepared in methanol, and the structure and molecular motions of this adduct were studied. The results showed that a six-membered heteroatom adduct was formed. One-dimensional and two-dimensional NMR spectroscopy was used to confirm the structure and assign some of the resonances in the proton and carbon spectra. Spin-lattice relaxation times of the various carbon atoms indicated that the overall molecular reorientation time (tau R) of the molecule is 0.02 ns at 30 degrees C. An Arrhenius plot of the data showed that the activation energy (Ea) for molecular tumbling is 13.4 kJ/mol.
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Affiliation(s)
- K Dill
- Department of Chemistry, Clemson University, South Carolina 29634
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Adams ER. Multivariate statistical methods for EEG analysis. Boll Soc Ital Biol Sper 1988; 64:101-8. [PMID: 3077905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Dill K, Adams ER, O'Connor RJ, Chong S, McGown EL. One-dimensional and two-dimensional nuclear magnetic resonance studies of the reaction of phenyldichloroarsine with glutathione. Arch Biochem Biophys 1987; 257:293-301. [PMID: 3662527 DOI: 10.1016/0003-9861(87)90569-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
14C-labeled phenyldichloroarsine (PDA) enters the red blood cell and forms a 1:2 adduct with intracellular glutathione. Upon gel filtration of the hemolysate, [14C]PDA was recovered with the glutathione-containing fractions. One-dimensional and two-dimensional nuclear magnetic resonance spectroscopy were used to confirm the structure of the adduct and elucidate its stereochemistry, stability, and reactivity.
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Affiliation(s)
- K Dill
- Department of Chemistry, Clemson University, South Carolina 29634-1905
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Hirsch KS, Adams ER, Hoffman DG, Markham JK, Owen NV. Studies to elucidate the mechanism of fenarimol-induced infertility in male rats. Toxicol Appl Pharmacol 1986; 86:391-9. [PMID: 3787632 DOI: 10.1016/0041-008x(86)90366-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Fenarimol (alpha-(2-chlorophenyl)-alpha-(4-chlorophenyl)-5- pyrimidinemethanol a pyrimidine carbinol fungicide, caused a dose-related decrease in male fertility in Wistar rats. The effect was particularly evident in the anatomically normal progeny of dams treated with fenarimol throughout gestation and lactation. Based on the observation that the infertility was associated with the absence of vaginal sperm at the time of mating, the effect appeared to be the result of an absence of male sexual behavior. Fenarimol does not readily cross the placenta but does concentrate in milk, reaching three- to fivefold higher concentrations than those observed in the maternal plasma. These results suggest that fenarimol might be acting to block the perinatal development of male patterns of sexual behavior which involves the action of gonadal steroids within the central nervous system (CNS). To test this hypothesis, [14C]fenarimol was administered to dams and the radioactivity measured in the brains of the neonates. Radioactivity in the hypothalamus was three- to fourfold higher and the half-life four times longer than that observed in the remainder of the brain. Since the hypothalamus is believed to play a key role in the development and expression of male sexual behavior, it appears likely that fenarimol is acting centrally to decrease male sexual behavior, thereby decreasing male fertility.
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Adams ER. Electrosurgery is an aid to gingival retraction. Dent Stud 1973; 52:30-1, 84. [PMID: 4529790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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