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Raymond J, Gentric JC, Magro E, Nico L, Bacchus E, Klink R, Cognard C, Januel AC, Sabatier JF, Iancu D, Weill A, Roy D, Bojanowski MW, Chaalala C, Barreau X, Jecko V, Papagiannaki C, Derrey S, Shotar E, Cornu P, Eker OF, Pelissou-Guyotat I, Piotin M, Aldea S, Beaujeux R, Proust F, Anxionnat R, Costalat V, Corre ML, Gauvrit JY, Morandi X, Brunel H, Roche PH, Graillon T, Chabert E, Herbreteau D, Desal H, Trystram D, Barbier C, Gaberel T, Nguyen TN, Viard G, Gevry G, Darsaut TE, _ _, _ _, Raymond J, Roy D, Weill A, Iancu D, Bojanowski MW, Chaalala C, Darsaut TE, O’Kelly CJ, Chow MMC, Findlay JM, Rempel JL, Fahed R, Lesiuk H, Drake B, Santos MD, Gentric JC, Nonent M, Ognard J, El-Aouni MC, Magro E, Seizeur R, Timsit S, Pradier O, Desal H, Boursier R, Thillays F, Roualdes V, Piotin M, Blanc R, Aldea S, Cognard C, Januel AC, Sabatier JF, Calviere L, Gauvrit JY, Raoult H, Eugene F, Bras AL, Ferre JC, Paya C, Morandi X, Lecouillard I, Nouhaud E, Ronziere T, Trystram D, Naggara O, Rodriguez-Regent C, Kerleroux B, Barbier C, Gaberel T, Emery E, Touze E, Papagiannaki C, Derrey S, Eker OF, Riva R, Pellisou-Guyotat I, Guyotat J, Berhouma M, Dumot C, Biondi A, Thines L, Bougaci N, Charbonnier G, Bracard S, Anxionnat R, Gory B, Civit T, Bernier-Chastagner V, Barreau X, Marnat G, Jecko V, Penchet G, Gimbert E, Huchet A, Herbreteau D, Boulouis G, Bibi R, Ifergan H, Janot K, Velut S, Brunel H, Roche PH, Graillon T, Peyriere H, Kaya JM, Touta A, Troude L, Boissonneau S, Clarençon F, Shotar E, Sourour N, Lenck S, Premat K, Boch AL, Cornu P, Nouet A, Costalat V, Bonafe A, Dargazanli C, Gascou G, Lefevre PH, Riquelme C, Corre ML, Beaujeux R, Pop R, Proust F, Cebula H, Ollivier I, Spatola G, Spell L, Chalumeau V, Gallas S, Ikka L, Mihalea C, Ozanne A, Caroff J, Chabert E, Mounayer C, Rouchaud A, Caire F, Ricolfi F, Thouant P, Cao C, Mourier KL, Farah W, Nguyen TN, Abdalkader M, Huynh T, Tawk RG, Carlson AP, Silva LAO, Froio NDL, Silva GS, Mont’Alverne FJA, Martins JL, Mendes GN, Miranda RR. Endovascular treatment of brain arteriovenous malformations: clinical outcomes of patients included in the registry of a pragmatic randomized trial. J Neurosurg 2022; 138:1393-1402. [PMID: 37132535 DOI: 10.3171/2022.9.jns22987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 09/01/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVE
The role of endovascular treatment in the management of patients with brain arteriovenous malformations (AVMs) remains uncertain. AVM embolization can be offered as stand-alone curative therapy or prior to surgery or stereotactic radiosurgery (SRS) (pre-embolization). The Treatment of Brain AVMs Study (TOBAS) is an all-inclusive pragmatic study that comprises two randomized trials and multiple registries.
METHODS
Results from the TOBAS curative and pre-embolization registries are reported. The primary outcome for this report is death or dependency (modified Rankin Scale [mRS] score > 2) at last follow-up. Secondary outcomes include angiographic results, perioperative serious adverse events (SAEs), and permanent treatment-related complications leading to an mRS score > 2.
RESULTS
From June 2014 to May 2021, 1010 patients were recruited in TOBAS. Embolization was chosen as the primary curative treatment for 116 patients and pre-embolization prior to surgery or SRS for 92 patients. Clinical and angiographic outcomes were available in 106 (91%) of 116 and 77 (84%) of 92 patients, respectively. In the curative embolization registry, 70% of AVMs were ruptured, and 62% were low-grade AVMs (Spetzler-Martin grade I or II), while the pre-embolization registry had 70% ruptured AVMs and 58% low-grade AVMs. The primary outcome of death or disability (mRS score > 2) occurred in 15 (14%, 95% CI 8%–22%) of the 106 patients in the curative embolization registry (4 [12%, 95% CI 5%–28%] of 32 unruptured AVMs and 11 [15%, 95% CI 8%–25%] of 74 ruptured AVMs) and 9 (12%, 95% CI 6%–21%) of the 77 patients in the pre-embolization registry (4 [17%, 95% CI 7%–37%] of 23 unruptured AVMs and 5 [9%, 95% CI 4%–20%] of 54 ruptured AVMs) at 2 years. Embolization alone was confirmed to occlude the AVM in 32 (30%, 95% CI 21%–40%) of the 106 curative attempts and in 9 (12%, 95% CI 6%–21%) of 77 patients in the pre-embolization registry. SAEs occurred in 28 of the 106 attempted curative patients (26%, 95% CI 18%–35%, including 21 new symptomatic hemorrhages [20%, 95% CI 13%–29%]). Five of the new hemorrhages were in previously unruptured AVMs (n = 32; 16%, 95% CI 5%–33%). Of the 77 pre-embolization patients, 18 had SAEs (23%, 95% CI 15%–34%), including 12 new symptomatic hemorrhages [16%, 95% CI 9%–26%]). Three of the hemorrhages were in previously unruptured AVMs (3/23; 13%, 95% CI 3%–34%).
CONCLUSIONS
Embolization as a curative treatment for brain AVMs was often incomplete. Hemorrhagic complications were frequent, even when the specified intent was pre-embolization before surgery or SRS. Because the role of endovascular treatment remains uncertain, it should preferably, when possible, be offered in the context of a randomized trial.
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Affiliation(s)
- Jean Raymond
- Department of Radiology, Service of Neuroradiology, Centre hospitalier de l’Université de Montréal (CHUM), and CHUM Research Centre, Montréal, Québec, Canada
| | | | - Elsa Magro
- Department of Neurosurgery, CHU Cavale Blanche, INSERM UMR 1101 LaTIM, Brest, France
| | - Lorena Nico
- Department of Radiology, CHU Saint-Etienne, France
| | - Emma Bacchus
- Division of Neurosurgery, Department of Surgery, University of Alberta Hospital, Mackenzie Health Sciences Centre, Edmonton, Alberta, Canada
| | - Ruby Klink
- Department of Radiology, Service of Neuroradiology, Centre hospitalier de l’Université de Montréal (CHUM), and CHUM Research Centre, Montréal, Québec, Canada
| | | | | | - Jean-François Sabatier
- Neurosurgery, Pierre-Paul Riquet Hospital, Toulouse University Hospital, Toulouse, France
| | - Daniela Iancu
- Department of Radiology, Service of Neuroradiology, Centre hospitalier de l’Université de Montréal (CHUM), and CHUM Research Centre, Montréal, Québec, Canada
| | - Alain Weill
- Department of Radiology, Service of Neuroradiology, Centre hospitalier de l’Université de Montréal (CHUM), and CHUM Research Centre, Montréal, Québec, Canada
| | - Daniel Roy
- Department of Radiology, Service of Neuroradiology, Centre hospitalier de l’Université de Montréal (CHUM), and CHUM Research Centre, Montréal, Québec, Canada
| | - Michel W. Bojanowski
- Department of Surgery, Division of Neurosurgery, Centre hospitalier de l’Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Chiraz Chaalala
- Department of Surgery, Division of Neurosurgery, Centre hospitalier de l’Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Xavier Barreau
- Neuroradiology Department, Pellegrin Hospital Group, CHU Bordeaux, France
| | - Vincent Jecko
- Neurosurgery Department A, Pellegrin Hospital Group, CHU Bordeaux, France
| | | | - Stéphane Derrey
- Neurosurgery, Charles Nicolle Hospital, Rouen Normandy University Hospital, Rouen, France
| | | | - Philippe Cornu
- Neurosurgery, Mercy Salpetriere Hospital AP-HP, Paris, France
| | | | | | | | - Sorin Aldea
- Neurosurgery, Adolphe de Rothschild Foundation Hospital, Paris, France
| | | | - François Proust
- Neurosurgery, Strasbourg University Hospitals, Strasbourg, France
| | - René Anxionnat
- Interventional Neuroradiology Department, University of Lorraine, Laboratory IADI INSERM U1254, CHRU Nancy, France
| | | | | | | | | | - Hervé Brunel
- Departments of Interventional Neuroradiology and
| | | | | | - Emmanuel Chabert
- Interventional Neuroradiology Department, CHU Clermont-Ferrand, France
| | - Denis Herbreteau
- Interventional Neuroradiology Department, Bretonneau Hospital, Tours, France
| | - Hubert Desal
- Interventional Neuroradiology Department, CHU de Nantes, France
| | - Denis Trystram
- Interventional Neuroradiology Department, University of Paris, INSERM U1266, IPNP, GHU Paris, France
- Psychiatry and Neurosciences, Sainte-Anne Hospital, Paris, France
| | | | | | - Thanh N. Nguyen
- Departments of Radiology,
- Neurology, and
- Neurosurgery, Boston Medical Center, Boston University School of Medicine, Boston, Massachusetts; and
| | | | - Guylaine Gevry
- Department of Radiology, Service of Neuroradiology, Centre hospitalier de l’Université de Montréal (CHUM), and CHUM Research Centre, Montréal, Québec, Canada
| | - Tim E. Darsaut
- Division of Neurosurgery, Department of Surgery, University of Alberta Hospital, Mackenzie Health Sciences Centre, Edmonton, Alberta, Canada
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Howson CP, Cedergren B, Giugliani R, Huhtinen P, Padilla CD, Palubiak CS, Santos MD, Schwartz IVD, Therrell BL, Umemoto A, Wang J, Zeng X, Zhao X, Zhong N, McCabe ERB. Corrigendum to Universal newborn screening: A roadmap for action molecular genetics and metabolism 124 (2018) 177-183. Mol Genet Metab 2019; 127:216-217. [PMID: 31230977 DOI: 10.1016/j.ymgme.2019.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- C P Howson
- Howson & Partners for Global Health, Santa Fe, NM, USA.
| | - B Cedergren
- Evans School of Public Policy & Governance, University of Washington, Seattle, WA, USA
| | - R Giugliani
- Medical Genetics Service, HCPA, Brazil; Department of Genetics, UFRGS, Porto Alegre, Brazil
| | - P Huhtinen
- International Society for Neonatal Screening (ISNS), Turku, Finland
| | - C D Padilla
- Department of Pediatrics, College of Medicine, University of the Philippines, Manila, Philippines
| | | | - M D Santos
- PerkinElmer Diagnostics, Inc., São Paulo, SP, Brazil
| | - I V D Schwartz
- Medical Genetics Service, HCPA, Brazil; Department of Genetics, UFRGS, Porto Alegre, Brazil
| | - B L Therrell
- National Newborn Screening and Global Resource Center (NNSGRC), University of Texas Health Science Center at San Antonio, Austin, TX, USA
| | - A Umemoto
- Westchester Children's Association, White Plains, NY, USA
| | - J Wang
- China Alliance of Translational Medicine for Maternal and Children Health, Hainan Provincial Hospital for Maternal and Children's Health, Haikou, China
| | - X Zeng
- The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - X Zhao
- Peking University Center of Medical Genetics, China Alliance of Translational Medicine for Maternal and Children Health, Beijing, China
| | - N Zhong
- Southern Medical University, Guangzhou, China; China Alliance of Translational Medicine for Maternal and Children Health, Beijing, China; New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - E R B McCabe
- Department of Pediatrics, UCLA School of Medicine, Los Angeles, CA, USA
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Howson CP, Cedergren B, Giugliani R, Huhtinen P, Padilla CD, Palubiak CS, Santos MD, Schwartz IVD, Therrell BL, Umemoto A, Wang J, Zeng X, Zhao X, Zhong N, McCabe ERB. Universal newborn screening: A roadmap for action. Mol Genet Metab 2018; 124:177-183. [PMID: 29884465 DOI: 10.1016/j.ymgme.2018.04.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/23/2018] [Accepted: 04/24/2018] [Indexed: 11/30/2022]
Abstract
Newborn screening (NBS) prevents morbidity and mortality by screening babies for selected disorders in the first days of life so that early diagnosis and treatment can be initiated. Congenital disorders impact an estimated 8 million or 6% of annual births worldwide, and of the top five that contribute 25% to the global burden of these disorders, three can be identified and managed by NBS. There are determined pockets of activity in Latin America, Sub-Saharan Africa, and the Asia Pacific region, where partnerships among government, non-governmental organizations, academia, the private sector and civil society are developing novel NBS programs that are both saving lives and preventing disability in those who survive.
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Affiliation(s)
- C P Howson
- Howson & Partners for Global Health, Santa Fe, NM, USA.
| | - B Cedergren
- Evans School of Public Policy & Governance, University of Washington, Seattle, WA, USA
| | - R Giugliani
- Medical Genetics Service, HCPA, Brazil; Department of Genetics, UFRGS, Porto Alegre, Brazil
| | - P Huhtinen
- International Society for Neonatal Screening (ISNS), Turku, Finland
| | - C D Padilla
- Department of Pediatrics, College of Medicine, University of the Philippines, Manila, Philippines
| | | | - M D Santos
- PerkinElmer Diagnostics, Inc., São Paulo, SP, Brazil
| | - I V D Schwartz
- Medical Genetics Service, HCPA, Brazil; Department of Genetics, UFRGS, Porto Alegre, Brazil
| | - B L Therrell
- National Newborn Screening and Global Resource Center (NNSGRC), University of Texas Health Science Center at San Antonio, Austin, TX, USA
| | - A Umemoto
- Westchester Children's Association, White Plains, NY, USA
| | - J Wang
- China Alliance of Translational Medicine for Maternal and Children Health, Hainan Provincial Hospital for Maternal and Children's Health, Haikou, China
| | - X Zeng
- The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - X Zhao
- Peking University Center of Medical Genetics, China Alliance of Translational Medicine for Maternal and Children Health, Beijing, China
| | - N Zhong
- Southern Medical University, Guangzhou, China; China Alliance of Translational Medicine for Maternal and Children Health, Beijing, China; New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - E R B McCabe
- Department of Pediatrics, UCLA School of Medicine, Los Angeles, CA, USA
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Prado E, Herrera L, Vazquez V, Toscano MD, Santos MD. CP-210 Economic impact of obesity and overweight in the infliximab treatment in a tertiary hospital. Eur J Hosp Pharm 2016. [DOI: 10.1136/ejhpharm-2016-000875.210] [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: 11/03/2022] Open
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Pimentel MAF, Santos MD, Arteta C, Domingos JS, Maraci MA, Clifford GD. Respiratory rate estimation from the oscillometric waveform obtained from a non-invasive cuff-based blood pressure device. 2014 36TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY 2014; 2014:3821-4. [PMID: 25570824 DOI: 10.1109/embc.2014.6944456] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Santos MD, Dorogovtsev SN, Mendes JFF. Biased imitation in coupled evolutionary games in interdependent networks. Sci Rep 2014; 4:4436. [PMID: 24658580 PMCID: PMC3963071 DOI: 10.1038/srep04436] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 02/27/2014] [Indexed: 11/09/2022] Open
Abstract
We explore the evolutionary dynamics of two games—the Prisoner's Dilemma and the Snowdrift Game—played within distinct networks (layers) of interdependent networks. In these networks imitation and interaction between individuals of opposite layers is established through interlinks. We explore an update rule in which revision of strategies is a biased imitation process: individuals imitate neighbors from the same layer with probability p, and neighbors from the second layer with complementary probability 1 − p. We demonstrate that a small decrease of p from p = 1 (which corresponds to forbidding strategy transfer between layers) is sufficient to promote cooperation in the Prisoner's Dilemma subpopulation. This, on the other hand, is detrimental for cooperation in the Snowdrift Game subpopulation. We provide results of extensive computer simulations for the case in which layers are modelled as regular random networks, and support this study with analytical results for coupled well-mixed populations.
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Affiliation(s)
- M D Santos
- Department of Physics & I3N, University of Aveiro, 3810-193 Aveiro, Portugal
| | - S N Dorogovtsev
- 1] Department of Physics & I3N, University of Aveiro, 3810-193 Aveiro, Portugal [2] A. F. Ioffe Physico-Technical Institute, 194021 St. Petersburg, Russia
| | - J F F Mendes
- Department of Physics & I3N, University of Aveiro, 3810-193 Aveiro, Portugal
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Santos MD, Gomes MTSR. Starch viscoelastic properties studied with an acoustic wave sensor. Carbohydr Polym 2013; 99:68-73. [PMID: 24274480 DOI: 10.1016/j.carbpol.2013.08.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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: 12/12/2012] [Revised: 07/31/2013] [Accepted: 08/07/2013] [Indexed: 11/28/2022]
Abstract
Gelatinization and retrogradation of starch was followed in real time with an acoustic wave sensor. This study relies on the monitorization of the frequency of oscillation of a piezoelectric quartz crystal in contact with a 2.5% emulsion of a commercial maize starch, during heating and cooling. The technique showed to be very powerful and sensitive to most of the changes described in the literature, which have been elucidated by some other techniques. The value for the temperature of gelatinization found using the sensor was confirmed by the analysis of the same starch emulsion by polarized light microscopy. Temperatures of gelatinization were found to vary with the sample heating rate, as follows: 73.5 °C at 2.0 °C/min, 66.0 °C at 1.0 °C/min, and 65.0 °C at 0.5 °C/min. Hysteresis of the studied system was evidenced by the frequency shift before heating and after cooling till the initial temperature. Analysis performed on a 1.5% emulsion of a rice starch heated at 2.0 °C/min and cooled as before, evidenced no hysteresis and showed complete reversibility, in which concerns to the series frequency of the piezoelectric quartz crystal.
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Affiliation(s)
- M D Santos
- CESAM/Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
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Willette DA, Santos MD, Aragon MA. First report of the Taiwan sardinella Sardinella hualiensis (Clupeiformes: Clupeidae) in the Philippines. J Fish Biol 2011; 79:2087-2094. [PMID: 22141909 DOI: 10.1111/j.1095-8649.2011.03133.x] [Citation(s) in RCA: 7] [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] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A range expansion of the Taiwan sardinella Sardinella hualiensis to the Philippines is reported. The data suggested that the southern translocation of S. hualiensis occurred across oceanographic features that are typically barriers to small, pelagic fish dispersal. With this addition, the Philippines is among the most diverse countries for Sardinella biodiversity in the world, second only to India.
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Affiliation(s)
- D A Willette
- Old Dominion University, Department of Biological Sciences, 207 Mills Godwin Building, Norfolk, VA 23508, USA.
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Quiazon KMA, Yoshinaga T, Santos MD, Ogawa K. Identification of larval Anisakis spp. (Nematoda: Anisakidae) in Alaska pollock (Theragra chalcogramma) in northern Japan using morphological and molecular markers. J Parasitol 2009; 95:1227-32. [PMID: 19413366 DOI: 10.1645/ge-1751.1] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Accepted: 04/30/2009] [Indexed: 11/10/2022] Open
Abstract
The Alaska pollock, Theragra chalcogramma (Pallas), is an important raw source for surimi and other food products in Japan. However, Alaska pollock caught in the Atlantic and Mediterranean regions has been reported to harbor Anisakis species that pose considerable food safety problems. Here, we identified the third-stage (L3) Anisakis spp. sampled from Alaska pollock caught in northern Japan using a combination of morphological and molecular analyses which included PCR-RFLP and sequencing of the ITS (ITS1-5.8S rDNA-ITS2) region and mtDNA cox2 gene markers. Four Anisakis spp. were confirmed, namely Anisakis simplex (sensu stricto [s.s.]), A. pegreffii, A. brevispiculata, and an Anisakis sp. belonging to the Anisakis Type II group. The identification of 4 different Anisakis spp. occurring in Alaska Pollock, and the identification of A. brevispiculata and an Anisakis sp. (Anisakis Type II) in the northwest Pacific region, are first reports. Anisakis simplex (s.s.) composed the majority of Anisakis spp. in Alaska pollock at 91.0%, followed by A. pegreffii (5.2%), Anisakis sp. (Anisakis Type II) (2.4%), and A. brevispiculata (1.4%).
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Affiliation(s)
- K M A Quiazon
- Freshwater Aquaculture Center and College of Fisheries, Central Luzon State University, Science City of Muñoz, Nueva Ecija 3120, Philippines
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Santos MD, Brasil-Sato MC. Parasitic community of Fransciscodoras marmoratus (Reinhardt, 1874) (Pisces: Siluriformes, Doradidae) from the upper São Francisco River, Brazil. BRAZ J BIOL 2007; 66:931-8. [PMID: 17119841 DOI: 10.1590/s1519-69842006000500019] [Citation(s) in RCA: 8] [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] [Received: 10/01/2004] [Accepted: 02/03/2005] [Indexed: 11/22/2022] Open
Abstract
One hundred and thirteen specimens of Franciscodoras marmoratus (Reinhardt, 1874) were collected in the upper São Francisco River (18 degrees 12' 32" S, 45 degrees 15' 41" W, state of Minas Gerais) between September, 1999 and January, 2004 to investigate their parasite fauna. From this total, 45 (39.8%) were afflicted by at least one parasite species. The parasitic richness consisted of six species represented by Hirudinea (n = 20), Monogenoidea (n = 25), Eucestoda (n = 55), Nematoda (n = 1, n = 2) and Acanthocephala (n = 41) found in the dry and wet periods making a total of 144 specimens. Proteocephalus renaudi Chambrier & Vaucher, 1994 was the only species with prevalence higher than 10% and a typical aggregate distribution pattern. The prevalence, intensity and abundance of P. renaudi were not influenced by the total length or sex of the hosts or by the collection periods. The relative condition factor indicated that the health of the P. renaudi hosts was not significantly affected in relation to fish not infected by parasites. The fish stocked in tanks before necropsy were opportunistically infested by Lernaea cyprinacea Yashuv, 1959. The various parasites found indicate that F. marmoratus is omnivorous and a potential definitive host. The parasite species, except for Acanthocephala, have expanded their known geographic distribution to the São Francisco River Basin. The parasite community was considered isolationist because of the low endoparasite diversity, infrapopulations with low intensity, lack of evidence of parasite interactions and sparse signs of parasite aggression against their hosts.
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Affiliation(s)
- M D Santos
- Departamento de Parasitologia Animal, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brazil
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Albuquerque EX, Santos MD, Alkondon M, Pereira EF, Maelicke A. Modulation of nicotinic receptor activity in the central nervous system: a novel approach to the treatment of Alzheimer disease. Alzheimer Dis Assoc Disord 2001; 15 Suppl 1:S19-25. [PMID: 11669505 DOI: 10.1097/00002093-200108001-00004] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [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: 11/25/2022]
Abstract
Impaired cholinergic function in the central nervous system is an early feature of Alzheimer disease (AD). Currently, cholinergic deficit is usually corrected by increasing the amount of acetylcholine in the synapse by inhibiting acetylcholinesterase (AChE). One of the most consistent cholinergic deficits in AD is the reduced expression of nicotinic acetylcholine receptors (nAChR) in the brain. Since these receptors are essential for learning and memory, restoring nicotinic cholinergic function is a promising approach to treating AD. Allosteric modulation of nAChR is a novel approach, which circumvents development of tolerance through long-term use of conventional nicotinic agonists. Allosteric modulators interact with receptor-binding sites distinct from those capable of recognizing the natural agonist. Positive allosteric modulation of nAChR activity has no effect on conductance of single channels; instead, by facilitating channel opening, it potentiates responses evoked by the interaction of the natural agonist with presynaptic and postsynaptic nAChR. Allosteric modulation of nAChR activity could therefore potentially produce a significant benefit in AD. One such allosteric modulator is galantamine. In addition to increasing nAChR activity, galantamine also inhibits AChE. This novel, dual mechanism of action distinguishes galantamine from many other AChE inhibitors. Galantamine has been shown to improve cognitive and daily function for at least 6 months in placebo-controlled trials, and to maintain these functions at baseline levels for at least 12 months in a 6-month open-label extension study. Galantamine has positive effects on nAChR expression, which are likely to contribute to its sustained efficacy in the treatment of AD patients.
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Affiliation(s)
- E X Albuquerque
- Department of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore 21201, USA.
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12
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García MJ, Santos MD, Fernández De Gatta MM, Otero MJ, Domínguez-Gil A. [Populational pharmacokinetics: An approach to the]. Enferm Infecc Microbiol Clin 2001; 19:219-28. [PMID: 11446910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- M J García
- Departamento de Farmacia y Tecnología Farmacéutica. Universidad de Salamanca. Servicio de Farmacia. Hospital Universitario de Salamanca
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13
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Santos MD, de la Matta M, Velasco I, Marenco ML. [Disseminated intravascular coagulation associated with the application of dinoprostone gel to the cervix uteri]. Med Clin (Barc) 2000; 115:518. [PMID: 11093878 DOI: 10.1016/s0025-7753(00)71611-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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14
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Chebabo SR, Santos MD, Albuquerque EX. The organophosphate sarin, at low concentrations, inhibits the evoked release of GABA in rat hippocampal slices. Neurotoxicology 1999; 20:871-82. [PMID: 10693968] [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: 02/15/2023]
Abstract
In the present study, the whole-cell mode of the patch-clamp technique was applied to neurons of the CA1 pyramidal layer of rat hippocampal slices to investigate the effects of the organophosphate (OP) sarin on field stimulation-evoked and on tetrodotoxin (TTX)-insensitive postsynaptic currents (PSCs) mediated by activation of type A gamma-aminobutyric acid (GABA) receptors or AMPA-type glutamate receptors. At 0.3-1 nM, sarin reduced the amplitude of GABA-mediated PSCs and had no effect on the amplitude of glutamatergic PSCs evoked by field stimulation of neurons synaptically connected to the neuron under study. The effect of sarin on evoked GABAergic PSCs was unrelated to cholinesterase inhibition, was partially reversed upon washing of the neurons with sarin-free external solution, and was mediated by a direct interaction of the OP with muscarinic acetylcholine receptors present on presynaptic GABAergic neurons. Sarin had no effect on the amplitude or kinetics of GABA- or glutamate-mediated miniature postsynaptic currents (MPSCs) recorded in the presence of the Na+-channel blocker TTX (300 nM), indicating that the OP does not interact with GABA(A) or glutamate receptors. Further, sarin did not alter the frequency of GABAergic or glutamatergic MPSCs, a finding that led to the conclusion that this OP does not affect the TTX-insensitive release of neurotransmitters. A selective reduction by sarin of the action potential-dependent release of GABA in the hippocampus can account for the occurrence of seizures in intoxicated subjects.
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Affiliation(s)
- S R Chebabo
- Department of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore 21201, USA
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15
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Abstract
This study evaluated the sectional gutta-percha obturation technique advocated by Lightspeed Technology, Inc. Single relatively straight-canaled teeth were prepared with rotary instruments and divided into three groups. Groups A and B served as controls and were obturated using laterally condensed gutta-percha and either Roth's 801 or Ketac-Endo sealer. Group C was obturated using the Lightspeed technique that included placement of a 5-mm apical section of gutta-percha, followed by backfill with Ketac-Endo sealer and a single gutta-percha cone. All teeth were suspended in India ink for 14 days then cleared. Four additional teeth, which were obturated as in group C then sectioned, revealed a tightly adapted apical section of gutta-percha with a very thin layer of sealer. However, voids were noted in the middle and coronal areas. There was no significant difference in apical microleakage among the three groups. The sectional method was significantly faster than lateral condensation and seems to offer promise as an effective obturation method.
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Affiliation(s)
- M D Santos
- Department of Endodontics, Wilford Hall Medical Center, Lackland AFB, TX, USA
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16
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Rocha ES, Santos MD, Chebabo SR, Aracava Y, Albuquerque EX. Low concentrations of the organophosphate VX affect spontaneous and evoked transmitter release from hippocampal neurons: toxicological relevance of cholinesterase-independent actions. Toxicol Appl Pharmacol 1999; 159:31-40. [PMID: 10448123 DOI: 10.1006/taap.1999.8733] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [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: 11/22/2022]
Abstract
In the present study, the patch-clamp technique was applied to cultured hippocampal neurons to evaluate the effects of the nerve agent VX on evoked and spontaneous postsynaptic currents mediated by gamma-aminobutyric acid (GABA) and glutamate. At 0.01 nM, VX reduced the amplitude of evoked GABAergic currents, and only at concentrations >1 nM did it decrease the amplitude of evoked glutamatergic currents. The effect of VX on GABAergic currents, which was partially reversible upon washing of the neurons with VX-free external solution, could be prevented by the muscarinic antagonist atropine. In contrast, the effect of VX on glutamatergic currents, which was not reversible upon washing, appears to be related to the VX-induced reduction of the amplitude and frequency of repetitively firing by action potentials. In the presence of the Na(+)-channel blocker tetrodotoxin (TTX), VX (>/=10 nM) increased the frequency of GABA- and glutamate-mediated miniature postsynaptic currents (MPSCs). This effect of VX was unrelated to cholinesterase inhibition and was Ca(2+) dependent. The lack of effect of VX on MPSC kinetics indicates that VX-induced alterations of evoked and spontaneous currents are exclusively due to alterations of the transmitter release processes. The ability of VX to affect transmitter release in the brain may underlie some of its neurotoxic effects and may provide the basis for the development of therapeutic countermeasures to treat and/or prevent VX-induced neurotoxicity.
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Affiliation(s)
- E S Rocha
- Department of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore, Maryland, 21201, USA
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17
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Rocha ES, Chebabo SR, Santos MD, Aracava Y, Albuquerque EX. An analysis of low level doses of cholinesterase inhibitors in cultured neurons and hippocampal slices of rats. Drug Chem Toxicol 1999; 21 Suppl 1:191-200. [PMID: 10028411 DOI: 10.3109/01480549809007411] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [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: 11/13/2022]
Abstract
Recent data indicate that the neurotoxic effects of organophosphate compounds, including those of the nerve agents VX and sarin, are not solely due to irreversible cholinesterase inhibition. In this study we applied the patch clamp technique to hippocampal neurons in culture and slices to investigate the effects of VX, sarin and huperzine A on transmitter release and the mechanisms related with such effects. The nerve agents VX and sarin at very low concentrations significantly reduced the evoked release of GABA and glutamate. This effect was dependent of the activation of muscarinic receptors. In the presence or absence of the Na(+)-channel blocker tetrodotoxin (TTX), VX increased the frequency of spontaneous glutamate and GABA-induced postsynaptic currents. The effect of VX on TTX-insensitive spontaneous currents appears to be unrelated to cholinesterase inhibition, because it could be detected even after cholinesterase was blocked by high concentrations of the nerve agent soman. The ability of the nerve gases to decrease evoked release of GABA and increase spontaneous transmitter release may underlie some of the neurotoxic effects of the compounds. Huperzine A did not affect spontaneous or evoked release of GABA and glutamate, suggesting that this compound may be a pure cholinesterase inhibitor and had no effect on postsynaptic GABAA or AMPA receptors.
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Affiliation(s)
- E S Rocha
- Department of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore 21201, USA
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18
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Schultz CS, Rodriguez RA, Chew EA, Dimaano C, Li FM, Santos MD, Nieto MC. Effects of beta2-microglobulin mutations on the alpha-1 helical region of H2-Ld. Immunogenetics 1998; 48:273-82. [PMID: 9716647 DOI: 10.1007/s002510050432] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 02/08/2023]
Abstract
Beta-2 microglobulin (beta2m)has been shown to have an effect on the structural and functional constraints that facilitate proper class I antigen presentation. To date, no evidence has pinpointed the beta2m-specific amino acids that play an integral role in affecting structure in and around the peptide binding region of class I. To delineate beta2m amino acid positions that affect the alpha-1 helical region, we generated a series of mutant beta2m proteins bearing precise amino acid substitutions. The amino acid positions chosen were based upon previous results which demonstrated that human beta2m association with H2-Ld altered the structure of the alpha-1/alpha-2 super-domain. beta2m mutant proteins were used in beta2m exchange assays with cells expressing H2-Ld. Following exchange, cells were assayed to determine whether mutant beta2m association resulted in structural alteration of class I extracellular domains. The alteration in H2-Ld structure was evidenced by an increase in the binding of an antibody (34-1-2), specific for the alpha-1 helical region of H2-Ld. Results demonstrated that amino acid substitutions in beta2m positions 33 and 53 led to a dramatic increase in the reactivity of the alpha-1 domain-specific antibody 34-1-2. Identifying beta2m amino acid positions that influence the structure of the peptide binding region may allow for a better understanding of cellular immune responses that center upon class I/beta2m expression.
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Affiliation(s)
- C S Schultz
- Department of Biological Sciences, California State University, Hayward, 25800 Carlos Bee Blvd., Hayward, CA 94542, USA
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Croubels S, Vermeersch H, De Backer P, Santos MD, Remon JP, Van Peteghem C. Liquid chromatographic separation of doxycycline and 4-epidoxycycline in a tissue depletion study of doxycycline in turkeys. J Chromatogr B Biomed Sci Appl 1998; 708:145-52. [PMID: 9653956 DOI: 10.1016/s0378-4347(97)00644-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Liver and muscle tissue residues of doxycycline in turkeys were determined following administration of 25 mg doxycycline x HCl/kg BW in the drinking water under field conditions. Quantitation was performed using a validated HPLC method with fluorescence detection. The method was able to separate doxycycline and its 4-epimer, 4-epidoxycycline. This epimer was found in both liver and muscle tissue. The detection limits of the method were estimated at 1.2 ng/g and 1.0 ng/g of doxycycline in liver and muscle tissue, respectively, using a signal-to-noise ratio of 3:1. The recovery of doxycycline was determined from spiked tissues and was 63+/-3.8% and 66+/-3.1% for liver and muscle, respectively (n = 6). Within-day and between-day imprecision, expressed as the R.S.D. was below 7.4%. Linear calibration curves (r>0.997) were obtained in spiked liver between 0 and 1500 ng/g and in spiked muscle between 0 and 500 ng/g. A good stability of doxycycline was observed in liver samples after storage for 22 days at -20 degrees C. The correlation between the residues in the liver and the muscle was expressed as the correlation coefficient r and was 0.9884. The depletion kinetics of doxycycline fitted a one-compartment model. The elimination half-life (T1/2) of doxycycline was 77.7 h and 78.0 h in muscle and liver, respectively. Furthermore, the residue depletion kinetics were used to establish a withdrawal period in conformity with official guidelines. The withdrawal times necessary to reach concentrations below maximum residue limits (MRLs), as imposed by the EU, were 12 days and 17 days for liver and muscle tissue, respectively.
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Affiliation(s)
- S Croubels
- Department of Pharmacology, Pharmacy and Toxicology, Faculty of Veterinary Medicine, University of Ghent, Merelbeke, Belgium
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Santos MD, Vermeersch H, Remon JP, Schelkens M, De Backer P, Ducatelle R, Haesebrouck F. Administration of doxycycline hydrochloride via drinking water to turkeys under laboratory and field conditions. Poult Sci 1997; 76:1342-8. [PMID: 9316108 DOI: 10.1093/ps/76.10.1342] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [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: 02/05/2023] Open
Abstract
A series of experiments were carried out in order to determine doxycycline hydrochloride (DoxHCl) plasma levels in 6-wk-old turkeys medicated via drinking water containing DoxHCl at a concentration of 250 mg/L under laboratory and field conditions. Maximal plasma concentration (Cmax) values of 5.7 (+/-1.0) microgram/mL and 4.9 (+/-1.4) micrograms/mL obtained after DoxHCl administration during 2 and 7 d, respectively, were not significantly different. A significant difference was found between the area under the plasma concentration-time profile, calculated between 0 and 168 h (AUC(0-168)), Cmax, and the minimal plasma concentration (Cmin) values obtained after medication with a DoxHCl solution at a concentration of 250 mg/L (431.9 +/- 96.6 micrograms.h/mL, 4.9 +/- 1.4 micrograms/mL and 0.7 +/- 0.3 microgram/mL) and after medication with a DoxHCl solution at a concentration of 750 mg/L (1,176.5 +/- 201.8 micrograms.h/mL, 12.5 +/- 2.7 micrograms/mL and 2.9 +/- 0.4 micrograms/mL), respectively. The increase in body weight was also significantly higher for turkeys medicated with a DoxHCl solution at a concentration of 750 mg/L (83.7 g/d) than for the lower concentration (35.6 g/d). The DoxHCl solution uptake significantly decreased with the increase of DoxHCl concentration. A Cmax value of 1.7 +/- 0.6 micrograms/mL and a Cmin value of 0.5 +/- 0.1 microgram/mL were observed during the field experiment. Water consumption under laboratory conditions was followed for tap water (70 +/- 50 mL/kg.d) and for a DoxHCl solution at a concentration of 250 mg/L supplemented with 1 g anhydrous citric acid/L (119 +/- 6 mL/kg.d) and revealed to be not significantly different. The variability was significantly higher for tap water than for the DoxHCl solution. The stability of the DoxHCl solution containing 1 g citric acid/L over 24 h was 99% expressed as the percentage of the initial concentration.
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Affiliation(s)
- M D Santos
- Laboratory of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, University of Gent, Belgium
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21
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Camara AL, Braga MF, Rocha ES, Santos MD, Cortes WS, Cintra WM, Aracava Y, Maelicke A, Albuguergue EX. Methamidophos: an anticholinesterase without significant effects on postsynaptic receptors or transmitter release. Neurotoxicology 1997; 18:589-602. [PMID: 9291508] [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: 02/05/2023]
Abstract
Methamidophos (O,S-dimethyl phosphoroamidothiolate, Tamaron), an organophosphate (OP) anticholinesterase of limited toxicity, is widely used as an insecticide and acaricide. To provide additional insight into the molecular basis of its action, we have used electrophysiological and biochemical techniques to study the effects of methamidophos on the neuromuscular junction of rat and frog and on the central nervous system of rat. Methamidophos has a relatively weak inhibitory action on cholinesterases in rat diaphragm muscle, brain and hippocampal homogenates, with IC50 values on the order of 20-20 microM. An even weaker anticholinesterase activity was found in frog muscle homogenates, with the IC50 being above 300 microM. As further evidence of anticholinesterase activity, methamidophos (1-100 microM) was able to reverse the blockade by d-tubocurarine (0.5-0.7 microM) of neuromuscular transmission in rat phrenic nerve-hemidiaphragm preparations. Inhibition of cholinesterase activity by methamidophos was long lasting, which is consistent with the formation by the agent of a covalent bond with the enzyme's active serine residue. The action was also slowly reversible, which suggests spontaneous reactivation of the enzyme. electrophysiological studies at the rat neuromuscular junction showed that, due to its anticholinesterase activity, methamidophos increased the amplitude and prolonged the decay phase of nerve-evoked and spontaneous miniature end-plate potentials. In contrast to other OP compounds, e.g., paraoxon (Rocha et al., 1996a), methamidophos did not affect neurotransmitter release, nor did it interact directly with the muscle nicotinic acetylcholine receptor. Moreover, it contrast to paraoxon, methamidophos did not affect the whole-cell currents induced by application of acetylcholine, glutamate or gamma-aminobutyric acid recorded to cultured hippocampal neurons. Based on these data, methamidophos appears to have a selective effect on cholinesterase.
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Affiliation(s)
- A L Camara
- Laboratory of Molecular Pharmacology II, Institute of Biophysics, Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil
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Santos MD, Vermeersch H, Remon JP, Schelkens M, De Backer P, Van Bree HJ, Ducatelle R, Haesebrouck F. Pharmacokinetics and bioavailability of doxycycline in turkeys. J Vet Pharmacol Ther 1996; 19:274-80. [PMID: 8866455 DOI: 10.1111/j.1365-2885.1996.tb00049.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [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: 02/02/2023]
Abstract
The pharmacokinetic parameters of doxycycline (DOX) were determined in 3 day, 3-, 6- and 12-week-old fasted turkeys, after a single intravenous (i.v.) dose of 25 mg doxycycline. HCl/kg body weight. Doxycycline disposition fitted an open two-compartment model. The mean (+/-SD) elimination half-life was 10.6 +/- 0.7, 10.8 +/- 1.5, 7.9 +/- 1.4 and 10.0 +/- 0.9 h in 3 day, 3-, 6- and 12-week-old turkeys, respectively. Mean (+/- SD) total body clearance was 0.19 (+/-0.01), 0.27 (+/-0.03), 0.11 (+/-0.03) and 0.06 (+/-0.01) L/h.kg in 3 day, 3-, 6- and 12-week-old turkeys, respectively. The steady-state volume of distribution was 1.77 (+/-0.2), 2.1 (+/-0.2), 0.7 (+/-0.4) and 0.5 (+/-0.2) L/kg in turkeys of the above mentioned ages, respectively. The AUC value significantly increased with the age of the turkeys. An oral doxycycline solution at a single dose of 25 mg/kg of body weight was administered to 3 day. 3-, 6- and 12-week-old turkeys. The maximal plasma concentrations in fasted turkeys were 3.8, 5.6, 7.4 and 5.7 micrograms/mL. with tmax values of 4.7, 1.5, 2.8 and 5.4 h, for the different ages, respectively. In fed turkeys the Cmax values were 2.5, 6.1, 4.8 and 3.0 micrograms/mL. with tmax values of 4.2, 5.3, 4.5 and 7.5 h, respectively. The absolute bioavailability in fasted turkeys varied between 25.0 +/- 9.0% (for 12-week-old birds) and 63.5 +/- 7.1% (for 3-week-old birds). The relative bioavailability varied between 40.0 +/- 13.0% (for 12-week-old birds) and 83.7 +/- 14.3% (for 3-week-old birds).
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Affiliation(s)
- M D Santos
- Laboratory of Pharmaceutical Technology, Faculty of Pharmacy, University of Gent, Belgium
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Santos MD, Vermeersch H, Remon JP, Schelkens M, De Backer P, Ducatelle R, Haesebrouck F. Validation of a high-performance liquid chromatographic method for the determination of doxycycline in turkey plasma. J Chromatogr B Biomed Appl 1996; 682:301-8. [PMID: 8844423 DOI: 10.1016/0378-4347(96)00076-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A high-performance liquid chromatographic method for the analysis of doxycycline in turkey plasma samples using demeclocycline hydrochloride as the internal standard was developed, optimized and validated. A one-step extraction procedure and an isocratic HPLC method with UV detection were used. No interferences with endogenous compounds or with the anticoagulant were observed. Linear calibration curves (r2 > 0.99) were obtained in water and plasma between 0 and 600 micrograms ml-1. Good recoveries for doxycycline (> 66%) and demeclocycline (> 72%) were seen both in water and in plasma. The coefficient of variation was < 9.86% for within-day reproducibility and < 7.53% for the between-day reproducibility. The deviation between the mean value found and the true value was < 14.5% (accuracy). The limit of detection was 0.1 microgram ml-1 in plasma samples. A good stability of doxycycline was observed in water and in plasma samples after storage for six months at -20 degrees C (recovery > 91%).
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Affiliation(s)
- M D Santos
- Laboratory of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, University of Ghent, Belgium
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