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Rup B, Pallardy M, Sikkema D, Albert T, Allez M, Broet P, Carini C, Creeke P, Davidson J, De Vries N, Finco D, Fogdell-Hahn A, Havrdova E, Hincelin-Mery A, C Holland M, H Jensen PE, Jury EC, Kirby H, Kramer D, Lacroix-Desmazes S, Legrand J, Maggi E, Maillère B, Mariette X, Mauri C, Mikol V, Mulleman D, Oldenburg J, Paintaud G, R Pedersen C, Ruperto N, Seitz R, Spindeldreher S, Deisenhammer F. Standardizing terms, definitions and concepts for describing and interpreting unwanted immunogenicity of biopharmaceuticals: recommendations of the Innovative Medicines Initiative ABIRISK consortium. Clin Exp Immunol 2015; 181:385-400. [PMID: 25959571 PMCID: PMC4557374 DOI: 10.1111/cei.12652] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2015] [Indexed: 12/17/2022] Open
Abstract
Biopharmaceuticals (BPs) represent a rapidly growing class of approved and investigational drug therapies that is contributing significantly to advancing treatment in multiple disease areas, including inflammatory and autoimmune diseases, genetic deficiencies and cancer. Unfortunately, unwanted immunogenic responses to BPs, in particular those affecting clinical safety or efficacy, remain among the most common negative effects associated with this important class of drugs. To manage and reduce risk of unwanted immunogenicity, diverse communities of clinicians, pharmaceutical industry and academic scientists are involved in: interpretation and management of clinical and biological outcomes of BP immunogenicity, improvement of methods for describing, predicting and mitigating immunogenicity risk and elucidation of underlying causes. Collaboration and alignment of efforts across these communities is made difficult due to lack of agreement on concepts, practices and standardized terms and definitions related to immunogenicity. The Innovative Medicines Initiative (IMI; http://www.imi-europe.org), ABIRISK consortium [Anti-Biopharmaceutical (BP) Immunization Prediction and Clinical Relevance to Reduce the Risk; http://www.abirisk.eu] was formed by leading clinicians, academic scientists and EFPIA (European Federation of Pharmaceutical Industries and Associations) members to elucidate underlying causes, improve methods for immunogenicity prediction and mitigation and establish common definitions around terms and concepts related to immunogenicity. These efforts are expected to facilitate broader collaborations and lead to new guidelines for managing immunogenicity. To support alignment, an overview of concepts behind the set of key terms and definitions adopted to date by ABIRISK is provided herein along with a link to access and download the ABIRISK terms and definitions and provide comments (http://www.abirisk.eu/index_t_and_d.asp).
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Affiliation(s)
- B Rup
- Pfizer, Immunogenicity Sciences Disciple, Pharmacokinetics, Dynamics and Metabolism
| | - M Pallardy
- INSERM, UMR996, Faculté Pharmacie, Université Paris Sud, France
| | - D Sikkema
- GlaxoSmithKline, Clinical Immunology-Biopharm, King of Prussia, PA, USA
| | - T Albert
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - M Allez
- Hôpital Saint-Louis, Department of Gastroenterology, GETAID, Paris, France
| | - P Broet
- INSERM, UMR669, University of Paris Sud, France
| | - C Carini
- Pfizer, Early Biotech Clinical Development, Cambridge, MA, USA
| | - P Creeke
- Centre for Neuroscience and Trauma, Blizard Institute, Queen Mary University of London, London, UK
| | - J Davidson
- GlaxoSmithKline, Worldwide Epidemiology, Southall, UK
| | - N De Vries
- Clinical Immunology and Rheumatology, University of Amsterdam, Amsterdam, the Netherlands
| | - D Finco
- Pfizer, Drug Safety R&D, Groton, CT, USA
| | - A Fogdell-Hahn
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - E Havrdova
- Department of Neurology and Center for Clinical Neuroscience, MS Center, Charles University in Prague, Prague, Czech Republic
| | - A Hincelin-Mery
- Sanofi-Aventis, Clinical Exploratory and Pharmacology, Chilly-Mazerin, FR
| | - M C Holland
- GlaxoSmithKline, Clinical Immunology-Biopharm R&D, King of Prussia, PA, USA
| | - P E H Jensen
- Department of Neurology, University of Copenhagen, Copenhagen, Denmark
| | - E C Jury
- Centre for Rheumatology, University College London, London, UK
| | - H Kirby
- UCB Pharma, Bioanalytical R&D, Slough, UK
| | - D Kramer
- Merck-Serono, Institute of Drug Metabolism and Pharmacokinetics, Grafing, Germany
| | | | - J Legrand
- Ipsen Innovation, Pharmacokinetics Drug Metabolism Department, Les Ulis, France
| | - E Maggi
- Dipartimento di Medicina Sperimentale e Clinica, Universita di Firenze, Firenze, Italy
| | - B Maillère
- CEA-Saclay Institute of Biology and Technologies, Gif sur Yvette, France
| | - X Mariette
- INSERM, U1012, Hôpitaux Universitaires Paris Sud, Rhumatologie, Paris, France
| | - C Mauri
- Centre for Rheumatology Research, University College London, London, UK
| | - V Mikol
- Sanofi Aventis, Structural Biology, Paris, France
| | - D Mulleman
- University of Tours Francois Rabelais, CNRS UMR 7292, Tours, France
| | - J Oldenburg
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - G Paintaud
- CNRS UMR 7292 'GICC', Faculty of Medicine, Tours, France
| | | | - N Ruperto
- Istituto Giannina Gaslini, Pediatria II, Rheumatology, Genova, Italy
| | - R Seitz
- Division of Haematology/Transfusion Medicine, Paul-Ehrlich-Institut, Langen, Germany
| | - S Spindeldreher
- Drug Metabolism Pharmacokinetics-Biologics, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - F Deisenhammer
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
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Thiehoff C, Holland MC, Daniliuc C, Houk KN, Gilmour R. Can acyclic conformational control be achieved via a sulfur-fluorine gauche effect? Chem Sci 2015; 6:3565-3571. [PMID: 29511517 PMCID: PMC5659174 DOI: 10.1039/c5sc00871a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [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: 03/10/2015] [Accepted: 04/16/2015] [Indexed: 01/04/2023] Open
Abstract
The gauche conformation of the 1,2-difluoroethane motif is known to involve stabilising hyperconjugative interactions between donor (bonding, σC-H) and acceptor (antibonding, σ*C-F) orbitals. This model rationalises the generic conformational preference of F-Cβ-Cα-X systems (φFCCX ≈ 60°), where X is an electron deficient substituent containing a Period 2 atom. Little is known about the corresponding Period 3 systems, such as sulfur and phosphorus, where multiple oxidation states are possible. Conformational analyses of β-fluorosulfides, -sulfoxides and -sulfones are disclosed here, thus extending the scope of the fluorine gauche effect to the 3rd Period (F-C-C-S(O) n ; φFCCS ≈ 60°). Synergy between experiment and computation has revealed that the gauche effect is only pronounced in structures bearing an electropositive vicinal sulfur atom (S+-O-, SO2).
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Affiliation(s)
- C Thiehoff
- Organisch Chemisches Institut, and Excellence Cluster EXC 1003 , Cells in Motion , Westfälische Wilhelms-Universität Münster , Corrensstrasse 40 , Münster , Germany .
| | - M C Holland
- Organisch Chemisches Institut, and Excellence Cluster EXC 1003 , Cells in Motion , Westfälische Wilhelms-Universität Münster , Corrensstrasse 40 , Münster , Germany .
- Department of Chemistry and Biochemistry , University of California Los Angeles , 607 Charles E. Young Drive East , Los Angeles 90095-1569 , USA .
| | - C Daniliuc
- Organisch Chemisches Institut, and Excellence Cluster EXC 1003 , Cells in Motion , Westfälische Wilhelms-Universität Münster , Corrensstrasse 40 , Münster , Germany .
| | - K N Houk
- Department of Chemistry and Biochemistry , University of California Los Angeles , 607 Charles E. Young Drive East , Los Angeles 90095-1569 , USA .
| | - R Gilmour
- Organisch Chemisches Institut, and Excellence Cluster EXC 1003 , Cells in Motion , Westfälische Wilhelms-Universität Münster , Corrensstrasse 40 , Münster , Germany .
- Excellence Cluster EXC 1003 , Cells in Motion , Westfälische Wilhelms-Universität Münster , Münster , Germany
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3
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Holland MC, Metternich JB, Mück-Lichtenfeld C, Gilmour R. Cation–π interactions in iminium ion activation: correlating quadrupole moment & enantioselectivity. Chem Commun (Camb) 2015; 51:5322-5. [DOI: 10.1039/c4cc08520e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A cation–π interaction is operational in the addition of uncharged nucleophiles to iminium salts derived from MacMillan's 1st generation catalyst.
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Affiliation(s)
- M. C. Holland
- Organisch Chemisches Institut
- and Excellence Cluster EXC 1003
- Cells in Motion
- Westfälische Wilhelms-Universität Münster
- Münster
| | - J. B. Metternich
- Organisch Chemisches Institut
- and Excellence Cluster EXC 1003
- Cells in Motion
- Westfälische Wilhelms-Universität Münster
- Münster
| | - C. Mück-Lichtenfeld
- Organisch Chemisches Institut
- and Excellence Cluster EXC 1003
- Cells in Motion
- Westfälische Wilhelms-Universität Münster
- Münster
| | - R. Gilmour
- Organisch Chemisches Institut
- and Excellence Cluster EXC 1003
- Cells in Motion
- Westfälische Wilhelms-Universität Münster
- Münster
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Bush MA, Matthews JE, De Boever EH, Dobbins RL, Hodge RJ, Walker SE, Holland MC, Gutierrez M, Stewart MW. Safety, tolerability, pharmacodynamics and pharmacokinetics of albiglutide, a long-acting glucagon-like peptide-1 mimetic, in healthy subjects. Diabetes Obes Metab 2009; 11:498-505. [PMID: 19187286 DOI: 10.1111/j.1463-1326.2008.00992.x] [Citation(s) in RCA: 142] [Impact Index Per Article: 9.5] [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] [Indexed: 11/26/2022]
Abstract
AIMS Albiglutide is a glucagon-like peptide-1 (GLP-1) mimetic generated by genetic fusion of a dipeptidyl peptidase-IV-resistant GLP-1 dimer to human albumin. Albiglutide was designed to retain the therapeutic effects of native GLP-1 while extending its duration of action. This study was conducted to determine the pharmacokinetics and initial safety/tolerability profile of albiglutide in non-diabetic volunteers. METHODS In this single-blind, randomized, placebo-controlled trial, 39 subjects (18-60 years, body mass index 19.9-35.0 kg/m(2)) received placebo (n = 10) or escalating doses of albiglutide (n = 29) on days 1 and 8 in the following sequential cohorts: cohort 1: 0.25 + 1 mg; cohort 2: 3 + 6 mg; cohort 3: 16 + 24 mg; cohort 4: 48 + 60 mg; and cohort 5: 80 + 104 mg. Dose proportionality was evaluated based on area under the plasma drug concentration versus time curve [area under the curve (AUC((0-7 days)))] and maximum plasma drug concentration (C(max)) for cohorts 2-5 during week 1. RESULTS Albiglutide had a terminal elimination half-life (T(1/2)) of 6-8 days and time to maximum observed plasma drug concentration (T(max)) of 3-4 days. A greater-than-dose proportional increase in albiglutide exposure was observed. Albiglutide demonstrated a dose-dependent trend in reductions of glucose weighted mean AUC and fructosamine levels in healthy subjects. The incidence and severity of adverse events (AEs) was similar between placebo and albiglutide groups. Headache was the most frequent drug-related AE, followed by constipation, flatulence and nausea. CONCLUSIONS Albiglutide has a half-life that favours once weekly or less frequent dosing with an acceptable safety/tolerability profile in non-diabetic subjects.
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Affiliation(s)
- M A Bush
- GlaxoSmithKline, Research Triangle Park, NC, USA
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Long AR, Hogg WR, Holland MC, Balkan N, Ferrier RP. Frequency-dependent loss in sputtered amorphous germanium films Measurements at low temperatures. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01418618508242765] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- A. R. Long
- a Department of Natural Philosophy , University of Glasgow , Glasgow , G12 SQQ , Scotland
| | - W. R. Hogg
- b Department of Physics , University of Essex , Wivenhoe Park, Colchester , Essex , England
| | - M. C. Holland
- a Department of Natural Philosophy , University of Glasgow , Glasgow , G12 SQQ , Scotland
| | - N. Balkan
- a Department of Natural Philosophy , University of Glasgow , Glasgow , G12 SQQ , Scotland
| | - R. P. Ferrier
- a Department of Natural Philosophy , University of Glasgow , Glasgow , G12 SQQ , Scotland
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Fu KMC, Santori C, Stanley C, Holland MC, Yamamoto Y. Coherent population trapping of electron spins in a high-purity n-type GaAs semiconductor. Phys Rev Lett 2005; 95:187405. [PMID: 16383948 DOI: 10.1103/physrevlett.95.187405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Indexed: 05/05/2023]
Abstract
In high-purity n-type GaAs under a strong magnetic field, we are able to isolate a lambda system composed of two Zeeman states of neutral-donor-bound electrons and the lowest Zeeman state of bound excitons. When the two-photon detuning of this system is zero, we observe a pronounced dip in the excited-state photoluminescence, indicating the creation of the coherent population-trapped state. Our data are consistent with a steady-state three-level density-matrix model. The observation of coherent population trapping in GaAs indicates that this and similar semiconductor systems could be used for various electromagnetically induced transparency type experiments.
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Affiliation(s)
- Kai-Mei C Fu
- Quantum Entanglement Project, ICORP, JST, Edward L. Ginzton Laboratory, Stanford University, California 94305-4085, USA.
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Abstract
With an ever-increasing wealth of information made available to researchers from expanding genomic sequence and protein structure databases, traditional experimentation and research are being drastically revisited. The unidirectional study of single molecules and pathways is being replaced by a combinatorial and cross-disciplinary platform that investigates interactive biological systems and dynamic networks. The complement system constitutes an ideal paradigm of how this concept is being applied in the field of contemporary immunology. Our laboratory has adopted such a cross-disciplinary approach in elucidating key aspects of complement functions and determining the role of several complement proteins in both inflammatory and developmental processes. Here we discuss recent findings pertaining to the rational development of complement inhibitors, our studies on protein-protein interactions and our progress in the study of viral immune evasion and complement evolution. Furthermore, we present recent studies implicating complement components in complex developmental processes, such as organ regeneration, hematopoietic development, and stem cell engraftment.
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Affiliation(s)
- D Mastellos
- Protein Chemistry Laboratory, Department of Pathology and Laboratory Medicine, University of Pennsylvania, 401 Stellar-Chance Laboratories, Philadelphia, PA 19104, USA
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8
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Holland MC, Hassin S, Zohar Y. Seasonal fluctuations in pituitary levels of the three forms of gonadotropin-releasing hormone in striped bass, Morone saxatilis (Teleostei), during juvenile and pubertal development. J Endocrinol 2001; 169:527-38. [PMID: 11375123 DOI: 10.1677/joe.0.1690527] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [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] [Indexed: 11/27/2022]
Abstract
In most vertebrates, the development of a mature gonadotropin-releasing hormone (GnRH) secretory system is pivotal for the onset of puberty. The role of the three native GnRH forms, seabream (sb) GnRH, chicken (c) GnRH-II and salmon GnRH, in striped bass puberty remains elusive. This study examined the changes in pituitary GnRH levels throughout juvenile and pubertal development, a period encompassing 3 to 4 years. The levels of the two most abundant forms in the pituitary, sbGnRH and cGnRH-II (10:1), increased during the Fall and peaked prior to (cGnRH-II) or during (sbGnRH) the natural breeding season in March to May. In most cases, sbGnRH and cGnRH-II levels of maturing fish correlated to changes in oocyte diameter, gonadosomatic index and LH pituitary content. Interestingly, pituitaries of immature and maturing 2- and 3-year-old males and females contained similar amounts of all three GnRH forms. Additionally, pituitary sbGnRH and cGnRH-II levels in juvenile fish were relatively high and GnRH profiles showed a clear seasonality, similar to those of older, mature fish. These findings suggest a role for both sbGnRH and cGnRH-II in the regulation of gonadal development and indicate that, unlike some mammalian species, the timing of puberty in striped bass is not limited by a low activity of the GnRH system.
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Affiliation(s)
- M C Holland
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, 701 East Pratt Street, Baltimore, Maryland 21202, USA
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Hassin S, Holland MC, Zohar Y. Early maturity in the male striped bass, Morone saxatilis: follicle-stimulating hormone and luteinizing hormone gene expression and their regulation by gonadotropin-releasing hormone analogue and testosterone. Biol Reprod 2000; 63:1691-7. [PMID: 11090437 DOI: 10.1095/biolreprod63.6.1691] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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: 11/01/2022] Open
Abstract
Striped bass are seasonal breeding fish, spawning once a year during the spring. All 3-yr-old males are sexually mature; however, 60-64% of the fish mature earlier as 1- or 2-yr-old animals. The endocrine basis underlying early maturity in 2-yr-old males was studied at the molecular level by monitoring changes in pituitary beta FSH and beta LH mRNA levels by ribonuclease protection assay, and correlating these changes to stages of testicular development. In maturing males, the mRNA levels of beta FSH were elevated during early spermatogenesis, whereas beta LH mRNA levels peaked during spermiation. The appearance of spermatozoa in the testis was associated with a decrease in beta FSH mRNA and a rise in beta LH mRNA abundance. Immature males had lower levels of beta LH mRNA than maturing males, but there were no differences in beta FSH mRNA levels between immature and maturing males. The regulation of gonadotropin gene expression in 2-yr-old males was studied by the chronic administration of GnRH analogue (GnRHa) and testosterone (T), with or without pimozide (P) supplementation. In immature males, the combination of T and GnRHa stimulated a three- to fivefold increase in beta FSH and beta LH mRNA levels, but the same treatment had no effect on gonadotropin gene expression in maturing males. In addition, the coadministration of P to immature males suppressed the stimulatory effect of GnRHa and T on beta FSH and beta LH mRNA levels, suggesting that dopamine may have a novel role in regulating gonadotropin gene expression.
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Affiliation(s)
- S Hassin
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, Maryland 21202, USA
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10
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Rodríguez L, Carrillo M, Sorbera LA, Soubrier MA, Mañanós E, Holland MC, Zohar Y, Zanuy S. Pituitary levels of three forms of GnRH in the male European sea bass (Dicentrarchus labrax, L.) during sex differentiation and first spawning season. Gen Comp Endocrinol 2000; 120:67-74. [PMID: 11042012 DOI: 10.1006/gcen.2000.7533] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [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] [Indexed: 11/22/2022]
Abstract
In the present study, levels of three GnRH forms [seabream GnRH (sbGnRH), chicken GnRH-II (cGnRH-II), and salmon GnRH (sGnRH)] were analyzed in the pituitary of male sea bass during sex differentiation and the first spawning season. Plasma levels of gonadotropin (GTH-2), testosterone (T), and 11-ketotestosterone (11-KT) were determined during the same periods. All GnRH forms were present in the pituitary. sbGnRH levels were 9-fold higher than cGnRH-II and 17-fold higher than sGnRH levels. The highest GnRHs levels were detected in November 1995, when fish were 9 months old and when the gonads started to differentiate. Levels of the three forms decreased and remained low during the first spawning season, with the exception of sbGnRH, which showed a significant increase in November 1996. Plasma GTH-2 levels were lowest in November 1995, later increasing 2.5 times during the next months. During the first spawning season, plasma GTH-2 levels peaked in December 1996, 1 month after the peak of sbGnRH. During sex differentiation, plasma T levels were high in November 1995 but decreased over the next months, while levels of 11-KT remained low and unchanged. During the first spawning season, both steroids peaked in January 1997. These results suggest a possible role for all three GnRH forms in achieving gonadal differentiation, while sbGnRH may be the most relevant form in the regulation of the first spawning season in male sea bass. Moreover, GTH-2 and 11-KT may play important roles in gonadal maturation, since plasma GTH-2 and 11-KT levels were high throughout the period of spermiation.
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Affiliation(s)
- L Rodríguez
- Instituto de Acuicultura de Torre la Sal (CSIC), 12595 Ribera de Cabanes, Castellón, Spain
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Abstract
Puberty is the period during which full sexual development occurs and the capacity to reproduce is acquired. Despite its importance, our understanding of the endocrine regulation of puberty in lower vertebrates is still limited. The objective of the present study was to describe the changes in gonadal development and plasma steroid levels in a relatively late maturing species, the striped bass, during the first four years of life. In about 65% of the females, puberty was initiated during the third year. Although gonadosomatic index (GSI) and oocyte diameter increased during this year, this first cycle was characterized by a heterogeneous population of developing oocytes, a relatively low mean maximum oocyte diameter, and an absence of yolk granules in the oocytes. Plasma 17beta-estradiol (E(2)) levels were low in all three-year-old fish, suggesting that an insufficient stimulation of vitellogenin production by E(2) may underlie the lack of vitellogenin incorporation into developing oocytes. All monitored parameters increased during the fourth year, but were still below the values attained by older females. In about 60% of the males, puberty was initiated during the first year and all males were mature by the third year. During the first two years, several immature males initiated spermatogenesis without reaching full maturity. In mature males, mean GSI, plasma testosterone, and 11-ketotestosterone levels increased simultaneously, reaching higher values each subsequent year. Our results indicate that, similar to the situation in mammals, more than one reproductive cycle is required in striped bass before complete adulthood is reached.
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Affiliation(s)
- M C Holland
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, Maryland 21202, USA
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12
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Holland MC, Gothilf Y, Meiri I, King JA, Okuzawa K, Elizur A, Zohar Y. Levels of the native forms of GnRH in the pituitary of the gilthead seabream, Sparus aurata, at several characteristic stages of the gonadal cycle. Gen Comp Endocrinol 1998; 112:394-405. [PMID: 9843645 DOI: 10.1006/gcen.1998.7138] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.4] [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] [Indexed: 11/22/2022]
Abstract
Brains of the gilthead seabream, Sparus aurata, contain three different forms of gonadotropin-releasing hormone (GnRH): seabream (sb) GnRH, chicken (c) GnRH-II, and salmon (s) GnRH. In the present study, we developed three specific enzyme-linked-immunosorbent assays (ELISA) for sbGnRH, cGnRH-II, and sGnRH and used them to measure the levels of each GnRH form in the pituitary of male and female seabream at different stages of gametogenesis. The sensitivity was 6 pg/well for the sbGnRH assay, 7 pg/well for the cGnRH-II assay, and 2 pg/well for the sGnRH assay. Levels of each of the three GnRH forms were measured in pituitaries from fish sampled at the beginning of gonadal recrudescence and during the spawning season. Of the three forms, only sbGnRH and cGnRH-II were detected in the pituitary, irrespective of reproductive state or sex. Recrudescent fish had similar levels of sbGnRH and cGnRH-II in the pituitary. In sexually mature fish, the levels of sbGnRH were higher than those in recrudescent fish while pituitary cGnRH-II content remained unchanged. Consequently, sbGnRH levels were 3- to 17-fold higher than cGnRH-II levels in mature fish. Positive correlations also existed between pituitary sbGnRH content and pituitary and plasma gonadotropin (GtH) II levels. Surprisingly, mature 1-year-old males had significantly higher levels of sbGnRH in the pituitary than mature 3-year-old males, while pituitary and plasma GtH II levels were similar between these two groups. Although the reason for this difference in sbGnRH levels is unclear, a possible role of sbGnRH in the processes of puberty or sex-inversion is implied. Based on the present results, it can be suggested that in the gilthead seabream, sbGnRH is the most relevant form of GnRH in the control of reproduction.
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Affiliation(s)
- M C Holland
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, Maryland, 21202, USA
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Abstract
Although the literature records instances of acute epidural haematoma and acute subdural haematoma related to playing basketball, there has not been a report of chronic subdural haematoma as a basketball injury. With the burgeoning interest in this sport in the United Kingdom and Europe, the possibility of this particular neurotrauma increases. Such an injury, along with the diagnosis and management of this often insidious lesion, is documented in this case report.
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Affiliation(s)
- T M Keller
- Pacific Neurosciences Institute, Orinda, CA 94563, USA
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14
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Holland MC, Hassin S, Zohar Y. Effects of long-term testosterone, gonadotropin-releasing hormone agonist, and pimozide treatments on gonadotropin II levels and ovarian development in juvenile female striped bass (Morone saxatilis). Biol Reprod 1998; 59:1153-62. [PMID: 9780322 DOI: 10.1095/biolreprod59.5.1153] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [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: 11/01/2022] Open
Abstract
The ability of the juvenile female reproductive axis to respond to hormonal stimulation was investigated in a Perciform fish, the striped bass (Morone saxatilis) using various combinations of testosterone (T), GnRH agonist (GnRHa), and pimozide. A long-term treatment with T alone, or T in combination with GnRHa, increased pituitary gonadotropin II (GtH II) levels 2- and 3-fold, respectively, suggesting that T and GnRHa each stimulate GtH II accumulation. Release of the accumulated GtH II could be induced only by high doses of GnRHa in combination with T, indicating that GtH II synthesis and release require different levels of GnRH stimulation. The addition of the dopamine antagonist pimozide did not affect pituitary and plasma GtH II levels but, in response to an additional acute GnRHa challenge, inhibited the release of GtH II. Although ovarian development was slightly stimulated by a combined T and GnRHa treatment, vitellogenesis was generally not initiated. The present study demonstrated that the juvenile striped bass pituitary is responsive to hormonal stimulation, resulting in elevated levels of GtH II in the pituitary and plasma. However, increased plasma levels of GtH II did not result in precocious puberty, suggesting that additional factors are required for the initiation of ovarian development in this teleost.
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Affiliation(s)
- M C Holland
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, Maryland 21202, USA
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Undar A, Holland MC, Howelton RV, Benson CK, Ybarra JR, Miller OL, Rossbach MM, Runge TM, Johnson SB, Sako EY, Calhoon JH. Testing neonate-infant membrane oxygenators with the University of Texas neonatal pulsatile cardiopulmonary bypass system in vitro. Perfusion 1998; 13:346-52. [PMID: 9778720 DOI: 10.1177/026765919801300511] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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: 11/16/2022]
Abstract
Neurologic complications are already well documented after cardiopulmonary bypass (CPB) procedures in neonates and infants. Physiologic pulsatile flow CPB systems may be the alternative to the currently used steady-flow CPB circuits. In addition to the pulsatile pump, a membrane oxygenator should be chosen carefully, because only a few membrane oxygenators are suitable for physiologic pulsatile flow. We have tested four different types of neonate-infant membrane oxygenators for physiologic pulsatility with The University of Texas neonate-infant pulsatile CPB system in vitro. Evaluation criteria were based on mean ejection time, extracorporeal circuit (ECC) pressure, and upstroke of dp/dt. The results suggested that the Capiox 308 hollow-fibre membrane oxygenator produced the best physiologic pulsatile waveform according to the ejection time, ECC pressure, and the upstroke of dp/dt. The Minimax Plus and Masterflo Infant hollow-fibre membrane oxygenators also produced adequate pulsatile flow. Only the Variable Prime Cobe Membrane Lung (VPCML) Plus flat-sheet membrane oxygenator failed to reach the criteria for physiologic pulsatility. Depending on the oxygenator used, the lowest priming volume of the infant CPB circuit was 415 ml and the highest 520 ml.
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Affiliation(s)
- A Undar
- Department of Surgery, University of Texas Health Science Center at San Antonio 78284-7841, USA.
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Abstract
In the 19th century, American physicians were drawn to the renowned medical centers of Europe, beacons of excellence in all areas of clinical science, to complement and supplement medical education and training. Such Old World master surgeons as Victor Horsley and William Macewen constantly reported novel and innovative operative procedures, including a significant number of operations on the spine and spinal cord. In this same era, a number of American surgeons made important contributions to the emerging specialty of spine surgery. The lives and work of Alban Smith, Berthold Hadra, DeForest Willard, and Robert Abbe are submitted in this report as examples.
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Affiliation(s)
- T Keller
- Pacific Neurosciences Institute, Orinda, California, USA
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Rahman M, Davies JH, Larkin IA, Holland MC, Long AR, Williamson JG. Edge and bulk transport in variably connected quantum Hall conductor. Phys Rev B Condens Matter 1996; 54:16409-16412. [PMID: 9985756 DOI: 10.1103/physrevb.54.16409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Quest DO, Kindt GW, Holland MC, Spetzler RF, Sousa AA, Awad IA, Meyer FB, Ogilvy CS, Ojemann RG, Field EM. Indications for carotid endarterectomy. Surg Neurol 1996; 46:540-544. [PMID: 8956885] [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: 05/22/2023]
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Holland MC, Spetzler RF. Carotid endartectomy. Neuroimaging Clin N Am 1996; 6:939-56. [PMID: 8824142] [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: 02/02/2023]
Abstract
This article provides an in-depth review of carotid endarterectomy for the treatment of occlusive carotid disease. Topics range from preoperative diagnostic assessment to postoperative complications. Key issues related to operative management, including anesthetic technique, intraoperative monitoring, cerebral protection, anticoagulation therapy, and intraluminal shunting, are emphasized. Operative techniques are discussed and illustrated in detail.
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Affiliation(s)
- M C Holland
- Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona 85013, USA
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20
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Undar A, Runge TM, Miller OL, Felger MC, Lansing R, Korvick DL, Bohls FO, Ottmers SE, O'Dell BJ, Ybarra JR, Howelton RV, Mireles RZ, Benson CK, Holland MC, Calhoon JH. Design of a physiologic pulsatile flow cardiopulmonary bypass system for neonates and infants. Int J Artif Organs 1996; 19:170-6. [PMID: 8675361] [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: 02/01/2023]
Abstract
Cardiopulmonary bypass surgical techniques that allow a surgeon to operate on the infant's heart use an extracorporeal circuit consisting of a pump, oxygenator, arterial and venous reservoirs, cannulae, an arterial filter, and tubing. The extracorporeal technique currently used in infants and neonates is sometimes associated with neurologic damage. We are developing a modified cardiopulmonary bypass system for neonates that has been tested in vitro and in one animal in vivo. Unlike other extracorporeal circuits which use steady flow, this system utilizes pulsatile flow, a low prime volume (500 ml) and a closed circuit. During in vitro experiments, the pseudo patient's mean arterial pressure was kept constant at 40 mmHg and the extracorporeal circuit pressure did not exceed a mean pressure of 200 mmHg. In our single in vivo experiment, the primary objective was to determine whether physiologic pulsatility with a 10 F (3.3 mm) aortic cannula could be achieved. The results suggest that this is possible.
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Affiliation(s)
- A Undar
- Biomedical Engineering Program, College of Engineering, University of Texas at Austin, USA
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Hol V, Darhuber AA, Bauer G, Wang PD, Song YP, Torres CM, Holland MC. Elastic strains in GaAs/AlAs quantum dots studied by high-resolution x-ray diffraction. Phys Rev B Condens Matter 1995; 52:8348-8357. [PMID: 9979837 DOI: 10.1103/physrevb.52.8348] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Gumbs G, Huang D, Qiang H, Pollak FH, Wang PD, Holland MC. Electromodulation spectroscopy of an array of modulation-doped GaAs/Ga1-xAlxAs quantum dots: Experiment and theory. Phys Rev B Condens Matter 1994; 50:10962-10969. [PMID: 9975202 DOI: 10.1103/physrevb.50.10962] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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