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Beaumont NJ, Austen MC, Atkins JP, Burdon D, Degraer S, Dentinho TP, Derous S, Holm P, Horton T, van Ierland E, Marboe AH, Starkey DJ, Townsend M, Zarzycki T. Identification, definition and quantification of goods and services provided by marine biodiversity: implications for the ecosystem approach. MARINE POLLUTION BULLETIN 2007; 54:253-65. [PMID: 17266994 DOI: 10.1016/j.marpolbul.2006.12.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Accepted: 12/03/2006] [Indexed: 05/13/2023]
Abstract
This paper identifies and defines ecosystem goods and services provided by marine biodiversity. Case studies have been used to provide an insight into the practical issues associated with the assessment of marine ecosystem goods and services at specific locations. The aim of this research was to validate the definitions of goods and services, and to identify knowledge gaps and likely difficulties of quantifying the goods and services. A validated theoretical framework for the assessment of goods and services is detailed, and examples of the goods and services at a variety of case study areas are documented. These results will enable future assessments of marine ecosystem goods and services. It is concluded that the utilisation of this goods and services approach has the capacity to play a fundamental role in the Ecosystem Approach, by enabling the pressures and demands of society, the economy and the environment to be integrated into environmental management.
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Babbage G, Townsend M, Zojer N, Mockridge IC, Garand R, Barlogie B, Shaughnessy J, Stevenson FK, Sahota SS. IgM-expressing Waldenstrom's macroglobulinemia tumor cells reveal a potential for isotype switch events in vivo. Leukemia 2007; 21:827-30. [PMID: 17287856 DOI: 10.1038/sj.leu.2404538] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Walsh DM, Klyubin I, Shankar GM, Townsend M, Fadeeva JV, Betts V, Podlisny MB, Cleary JP, Ashe KH, Rowan MJ, Selkoe DJ. The role of cell-derived oligomers of Abeta in Alzheimer's disease and avenues for therapeutic intervention. Biochem Soc Trans 2006; 33:1087-90. [PMID: 16246051 DOI: 10.1042/bst20051087] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Burgeoning evidence suggests that soluble oligomers of Abeta (amyloid beta-protein) are the earliest effectors of synaptic compromise in Alzheimer's disease. Whereas most other investigators have employed synthetic Abeta peptides, we have taken advantage of a beta-amyloid precursor protein-overexpressing cell line (referred to as 7PA2) that secretes sub-nanomolar levels of low-n oligomers of Abeta. These are composed of heterogeneous Abeta peptides that migrate on SDS/PAGE as dimers, trimers and tetramers. When injected into the lateral ventricle of rats in vivo, these soluble oligomers inhibit hippocampal long-term potentiation and alter the memory of a complex learned behaviour. Biochemical manipulation of 7PA2 medium including immunodepletion with Abeta-specific antibodies and fractionation by size-exclusion chromatography allowed us to unambiguously attribute these effects to low-n oligomers. Using this paradigm we have tested compounds directed at three prominent amyloid-based therapeutic targets: inhibition of the secretases responsible for Abeta production, inhibition of Abeta aggregation and immunization against Abeta. In each case, compounds capable of reducing oligomer production or antibodies that avidly bind Abeta oligomers also ameliorate the synaptotoxic effects of these natural, cell-derived oligomers.
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Wilcock A, Chelin M, Hall M, Hamley N, Morrison B, Scrivener L, Townsend M, Treen K. The relationship between occupational balance and health: a pilot study. Occup Ther Int 2006. [DOI: 10.1002/oti.45] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Townsend M, MacIver DH, Bilku R. Platypnoea-orthodeoxia syndrome in association with an ascending aortic aneurysm. EUROPEAN JOURNAL OF ECHOCARDIOGRAPHY 2005; 8:50-2. [PMID: 16275101 DOI: 10.1016/j.euje.2005.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2005] [Revised: 09/17/2005] [Accepted: 09/29/2005] [Indexed: 10/25/2022]
Abstract
Platypnoea-orthodeoxia syndrome is a uncommon condition presenting with dyspnoea and cyanosis that are characteristically worse in the upright posture and improved by lying supine. We present the case of a patient with a thoracic aortic aneurysm and a patent foramen ovale who presented with platypnoea-orthodeoxia syndrome. Diagnosis was established using transoesophageal echocardiography. We suggest a mechanism for the development of dyspnoea and hypoxia in patients with this disorder.
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Lim SH, Zhang Y, Wang Z, Esler WV, Beggs D, Pruitt B, Hancock P, Townsend M. Maintenance rituximab after autologous stem cell transplant for high-risk B-cell lymphoma induces prolonged and severe hypogammaglobulinemia. Bone Marrow Transplant 2005; 35:207-8. [PMID: 15531902 DOI: 10.1038/sj.bmt.1704742] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Townsend M, MacIver DH. Constrictive pericarditis and pleuropulmonary fibrosis secondary to cabergoline treatment for Parkinson's disease. Heart 2004; 90:e47. [PMID: 15253989 PMCID: PMC1768376 DOI: 10.1136/hrt.2004.036236] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
A 63 year old man with a six year history of Parkinson's disease presented with signs of right heart failure following a knee replacement. Constrictive pericarditis was diagnosed and a radical pericardectomy performed. Six months later, the patient remained unwell with raised inflammatory markers. An inflammatory fibrotic reaction caused by cabergoline was diagnosed. He improved after cessation of cabergoline.
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Casey M, Finch CF, Mahoney M, Townsend M. Sport safety policies and practices in two rural Victorian communities. J Sci Med Sport 2004; 7:226-31. [PMID: 15362319 DOI: 10.1016/s1440-2440(04)80013-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Australian football and netball are the predominant sports played in rural Victoria, Australia. This exploratory study is the first to report the sport safety policies and practices adopted by junior Australian football and netball clubs in small rural communities. Eleven informants from four clubs completed a semi-structured interview and survey. Whilst the clubs performed a range of injury prevention activities, they did not have formal sports safety policies. Generally, netball informants reported fewer safety practices than football informants. Crucial factors influencing safety policies and practices were the reliance on volunteers and a lack of senior players. Barriers towards the adoption of safety policies and practices appeared to be related to rural population declines, a lack of qualified people and attitudes to injury in rural areas. Future research needs to identify how widespread this lack of sport safety policies and practices is across rural Australia and to identify strategies to overcome barriers to implementing them.
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Lim SH, Zhang Y, Wang Z, Varadarajan R, Smith P, Burris C, Townsend M. Umbilical cord blood transplant in hepatitis C-associated severe aplastic anemia. Bone Marrow Transplant 2003; 33:565-7. [PMID: 14688818 DOI: 10.1038/sj.bmt.1704390] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Townsend M, Burtchaell S, Shackleford J, James M. 3.6 The significance of atrial fibrillation occurring during acute myocardial infarction. Europace 2003. [DOI: 10.1016/eupace/4.supplement_1.a5-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Townsend M, Mahoney M, Jones JA, Ball K, Salmon J, Finch CF. Too hot to trot? exploring potential links between climate change, physical activity and health. J Sci Med Sport 2003; 6:260-5. [PMID: 14609142 DOI: 10.1016/s1440-2440(03)80019-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Based on an analysis of existing literature, this paper explores the links between climate change, physical activity and health. It highlights the importance of physical activity for health, explores current understandings of factors influencing participation in sport and physical activity, and develops some hypotheses about the ways in which climate change may impact on the factors influencing physical activity and thereby on the level of participation in physical activity. The paper argues that climate change has the potential to be a barrier to participation in physical activity, particularly in areas where temperatures are already relatively high, and that a reduction in physical activity across the population is likely to have detrimental health impacts. The need for research to clarify the nature and extent of the threat posed to physical activity participation is highlighted, as is the need to take into account the direct and indirect costs of any changes or reductions in physical activity in any assessment of the costs of climate change and/or its mitigation.
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Finch C, Mahoney M, Townsend M, Zazryn T. RURAL SPORTS AND RECREATIONAL INJURIES IN AUSTRALIA: WHAT DO WE KNOW? Aust J Rural Health 2003. [DOI: 10.1111/j.1440-1584.2003.tb00526.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Townsend M, Moore J, Mahoney M. Playing their part: the role of physical activity and sport in sustaining the health and well being of small rural communities. Rural Remote Health 2002; 2:109. [PMID: 15876137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023] Open
Abstract
It is widely recognised that the health of rural Australians is poor in comparison with their urban counterparts. Similarly, the role played by physical activity in maintaining health has been well researched and is well documented. However, little appears to have been published in recent years about the links between physical activity and health in rural communities. The objective of this article was to begin to address that gap. To achieve this, the article drew on research conducted in two small rural communities in Victoria Australia, and highlighted the role that physical activity and sport played in sustaining the health and wellbeing of individuals and communities in rural areas. Taking the World Health Organisation's definition of health (a state of complete physical, mental and social well-being and not merely the absence of disease) as its measure, the paper highlighted the many ways in which physical activity and sport in rural communities contribute to physical health, mental wellbeing and social cohesiveness. Based this finding, the authors suggest that physical activity and sport make a significant contribution to the health and wellbeing of rural people and their communities and suggest that further research is necessary to better define this apparent contribution.
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Haldeman S, Carey P, Townsend M, Papadopoulos C. Arterial dissections following cervical manipulation: the chiropractic experience. CMAJ 2001; 165:905-6. [PMID: 11599329 PMCID: PMC81498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
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Miller ED, Duus KM, Townsend M, Yi Y, Collman R, Reitz M, Su L. Human immunodeficiency virus type 1 IIIB selected for replication in vivo exhibits increased envelope glycoproteins in virions without alteration in coreceptor usage: separation of in vivo replication from macrophage tropism. J Virol 2001; 75:8498-506. [PMID: 11507195 PMCID: PMC115095 DOI: 10.1128/jvi.75.18.8498-8506.2001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Analysis of viral replication and pathogenicity after in vivo selection of human immunodeficiency virus type 1 (HIV-1) attenuated in vitro will help to define the functions involved in replication and pathogenesis in vivo. Using the SCID-hu Thy/Liv mouse and human fetal thymus organ culture as in vivo models, we previously defined HIV-1 env determinants (HXB2/LW) which were reverted for replication in vivo (L. Su et al., Virology 227:46-52, 1997). In this study, we examined the replication of four highly related HIV-1 clones directly derived from Lai/IIIB or after selection in vivo to investigate the envelope gp120 determinants associated with replication in macrophages and in the thymus models in vivo. The LW/C clone derived from the IIIB-infected laboratory worker and HXB2/LW both efficiently infected monocyte-derived macrophages (MDM) and the human thymus. Although the laboratory worker (LW) isolates showed altered tropism from IIIB, they still predominantly used CXCR4 as coreceptors for infecting peripheral blood mononuclear cells, macrophages, and the thymus. Interestingly, a single amino acid mutation in the V3 loop associated with resistance to neutralizing antibodies was also essential for the replication activity of the LW virus in the thymus models but not for its activity in infecting MDM. The LW virions were equally sensitive to a CXCR4 antagonist. We further demonstrated that the LW HIV-1 isolate selected in vivo produced more infectious viral particles that contained higher levels of the Env protein gp120. Thus, selection of the laboratory-attenuated Lai/IIIB isolate in vivo leads to altered tropism but not coreceptor usage of the virus. The acquired replication activity in vivo is correlated with an early A-to-T mutation in the V3 loop and increased virion association of HIV-1 Env gp120, but it is genetically separable from the acquired replication activity in macrophages.
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Shi J, Aamodt SM, Townsend M, Constantine-Paton M. Developmental depression of glutamate neurotransmission by chronic low-level activation of NMDA receptors. J Neurosci 2001; 21:6233-44. [PMID: 11487646 PMCID: PMC6763141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Slabs of slow-release plastic (Elvax) containing NMDA or solvent were implanted over the rat colliculus beginning on postnatal day 8 (P8). Whole-cell patch clamping in the superficial superior collicular layers (sSCs) from P10 to P21 demonstrated a severe decrease in spontaneous EPSC frequency after chronic NMDA treatment. The decrease was not attributable to an increase in GABA(A) receptor-mediated inhibition and was present only when NMDA receptor (NMDAR) current was blocked by Mg(2+). Analysis of miniature EPSCs indicated that many active sites on NMDA-treated neurons lacked functional AMPA and kainate receptor (AMPA/KAR) currents, and AMPA/KAR:NMDAR current ratios of evoked EPSCs were also significantly reduced. In addition, the normal downregulation of NMDAR decay time in sSC neurons at P11 was absent after NMDA treatment. Nevertheless, neither AMPA nor NMDA receptor subunit expression was altered by NMDA treatment, and experiments with the NMDAR antagonist ifenprodil suggested that incorporation of NR2A-containing NMDARs at the sSC synapses was unperturbed. Thus, disrupting but not blocking NMDARs suppresses the development of AMPA/KAR currents. The absence of the P11 NMDAR current downregulation is likely a secondary effect resulting from the reduction of AMPA/KAR function. Chronic agonist application reduces but does not eliminate NMDAR conductances. Therefore these data support an active role for NMDAR currents in synaptic development. Prolonged NMDA treatment in vivo, which couples reduced postsynaptic Ca(2+) responses with normally developing afferent activity, produces a long-lasting synaptic depression and stalls glutamatergic synaptogenesis, suggesting that the correlation between robust NMDAR activation and afferent activity is an essential component during normal development.
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Conway KP, Byrne J, Townsend M, Lane IF. Prognosis of patients turned down for conventional abdominal aortic aneurysm repair in the endovascular and sonographic era: Szilagyi revisited? J Vasc Surg 2001; 33:752-7. [PMID: 11296328 DOI: 10.1067/mva.2001.112800] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE The United Kingdom Small Aneurysm study has demonstrated the low risk of rupture in aneurysms less than 5.5 cm in diameter. With the advent of endoluminal techniques, patients considered unfit to undergo laparotomy are now considered for endovascular repair. However, the natural history of aneurysms larger than 5.5 cm remains uncertain, especially when severe comorbidity is present. In our center, we prospectively maintain records of all patients for whom elective aneurysm surgery was refused. This study documented the outcome of all patients referred with abdominal aortic aneurysms (AAAs) larger than 5.5 cm in diameter who were turned down for elective open repair and determined the cause of death and risk of rupture in all patients. METHODS Details of all patients with AAAs from January 5, 1989, to January 5, 1999, were recorded, and demographic details on all patients with AAAs larger than 5.5 cm were collected. Copies of death certificates were obtained from the Office of National Statistics, local in-hospital patient records, and general practitioner records. Results of postmortem examinations were also obtained. Aneurysms were stratified according to their size at presentation (5.5-5.9 cm, 6.0-7.0 cm, and > 7.0 cm), and the reasons no intervention was made were documented. RESULTS A total of 106 patients were turned down for elective aneurysm surgery in the 10-year period (10.6 per year). The mean age of the patients was 78.4 years (SD, 7.4), and 70 were men and 36 were women. At the end of the study, 76 patients (71.7%) had died. Overall, the 3-year survival rate was 17%. Patients with AAAs larger than 7.0 cm lived a median of 9 months. A ruptured aneurysm was certified as a cause of death in 36% of the patients with an AAA of 5.5 to 5.9 cm, in 50% of the patients with an AAA of 6 to 7.0 cm, and 55% of the patients with an AAA larger than 7.0 cm. Reasons given for not intervening were patient refusal (31 cases), the patient being "unfit for surgery" (18 cases), the "advanced age" of the patient (18 cases), cardiac disease (9 cases), cancer (9 cases), respiratory disease (6 cases), and other (15 cases). CONCLUSION Although we recognize the problems with death certification, we found that rupture was a significant cause of death in patients with an untreated AAA that was larger than 5.5 cm. Although little difference in outcome was observed in aneurysms in the 5.5 to 7.0 cm size range, patients with an AAA that was larger than 7.0 cm seemed to have a much poorer prognosis.
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Penn DL, Combs DR, Ritchie M, Francis J, Cassisi J, Morris S, Townsend M. Emotion recognition in schizophrenia: further investigation of generalized versus specific deficit models. JOURNAL OF ABNORMAL PSYCHOLOGY 2000. [PMID: 11016120 DOI: 10.1037//002i-843x.109.3.512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In this study, the authors examined the nature of emotion perception in schizophrenia. Two samples of people with schizophrenia, one receiving acute care for a recent exacerbation of symptoms and the other receiving extended care, were compared with a nonclinical control group on emotion perception and general perception measures. The nonclinical control group obtained the highest scores on all of the study measures, and the acutely ill group obtained the lowest scores. Furthermore, the acutely ill sample had a specific deficit in emotion perception that remained present after controlling for performance on the general perception tasks. Conversely, the deficits in emotion discrimination in the extended-care sample reflected generalized poor performance. Differences in performance on the emotion identification task between the 2 clinical groups were reduced when controlling for active symptoms.
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Shi J, Townsend M, Constantine-Paton M. Activity-dependent induction of tonic calcineurin activity mediates a rapid developmental downregulation of NMDA receptor currents. Neuron 2000; 28:103-14. [PMID: 11086987 DOI: 10.1016/s0896-6273(00)00089-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Whole-cell recording in the superficial layers of the developing superior colliculus (sSC) reveals a large drop in NMDA receptor (NMDAR) current decay time synchronized across all neurons and occurring consistently between P10 and P11. We show that blocking the Ca2+/calmodulin-dependent phosphatase calcineurin (CaN) in the postsynaptic neuron can abolish this drop. The regulation is induced prematurely by 1-2 hr of electrical stimulation in P10 collicular slices only if CaN and NMDAR currents can be activated in the neuron. These data suggest that a long-lasting, CaN-mediated control of NMDAR kinetics is rapidly initiated by heightened activity of the NMDAR itself and demonstrate a novel developmental and tonic function of CaN that can play an important role in modulating the plasticity of the developing CNS.
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Penn DL, Combs DR, Ritchie M, Francis J, Cassisi J, Morris S, Townsend M. Emotion recognition in schizophrenia: further investigation of generalized versus specific deficit models. JOURNAL OF ABNORMAL PSYCHOLOGY 2000. [PMID: 11016120 DOI: 10.1037/002i-843x.109.3.512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In this study, the authors examined the nature of emotion perception in schizophrenia. Two samples of people with schizophrenia, one receiving acute care for a recent exacerbation of symptoms and the other receiving extended care, were compared with a nonclinical control group on emotion perception and general perception measures. The nonclinical control group obtained the highest scores on all of the study measures, and the acutely ill group obtained the lowest scores. Furthermore, the acutely ill sample had a specific deficit in emotion perception that remained present after controlling for performance on the general perception tasks. Conversely, the deficits in emotion discrimination in the extended-care sample reflected generalized poor performance. Differences in performance on the emotion identification task between the 2 clinical groups were reduced when controlling for active symptoms.
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Kenley RA, Tracht S, Stepanenko A, Townsend M, L'Italien J. Kinetics of pramlintide degradation in aqueous solution as a function of temperature and pH. AAPS PharmSciTech 2000; 1:E7. [PMID: 14727840 PMCID: PMC2784819 DOI: 10.1208/pt010207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The stability of the 37-amino acid peptide pramlintide, in aqueous solution, was studied as a function of pH and temperature. Samples of pramlintide formulated as a parenteral product were exposed to elevated temperatures and to realistic storage conditions for as long as 30 months. Pramlintide degradation was monitored by three high-performance liquid chromatography (HPLC) methods: a reversed-phase (RP-HPLC) and a strong-cation exchange (SCX-HPLC) method for percentage purity determination by area normalization, plus a second RP-HPLC method for potency determination versus external standards. The pH-rate profile for pramlintide shows increasing degradation rate constants with increasing pH over the range pH = 3.5 to 5.0. The Arrhenius expression for pramlintide degradation at pH = 4.0 over the temperature range 5 degrees C to 50 degrees C is ln(k(0))= 37.39-21.900/RT, where k(0) is the zero-order rate constant (in %/mo) for pramlintide degradation. The pramlintide parenteral product formulated at pH = 4.0 is extremely stable, with percentage purity and percentage potency loss of only approximately 2% over 30 months at 5 degrees C. The formulated pramlintide drug product has acceptable shelf life for long-term storage at 5 degrees C and up to a 30-day patient use when stored at ambient temperature.
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Kenley RA, Bancroft F, L'Italien J, Stepanenko A, Townsend M, Dixit T. Pramlintide injection drug product robustness studies. AAPS PharmSciTech 2000; 1:E8. [PMID: 14727841 PMCID: PMC2784827 DOI: 10.1208/pt010208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The article examines the effects of temperature excursions and actual dose withdrawal on the quality of pramlintide injection, a multidose liquid parenteral formulation. Studies were designed to demonstrate product robustness under conditions that may occur during patient use. Pramlintide %Purity was determined by two high-performance liquid chromatography (HPLC) methods, a reversed-phase (RP-HPLC) and a strong-cation exchange (SCX-HPLC) method. A second RP-HPLC method was used to determine pramlintide potency and the concentration of the m-cresol preservative. Antimicrobial preservative effectiveness testing was per USP and European Pharmacopeia (Ph. Eur.). Short-term stability studies were undertaken to probe the effects of the following conditions: 5 degrees C to 40 degrees C and 5 degrees C to -20 degrees C temperature cycling over 10 days; once daily or four-times daily dose withdrawal over 12 or 42 days; and combined 30 degrees C storage and four-times daily dose withdrawal over 42 days. In all cases, pramlintide %Purity and potency values remained essentially unchanged or unchanged relative to controls. Similarly, product appearance, and m-cresol concentration and preservative effectiveness were not significantly affected by the stress conditions used in the 5 studies. Pramlintide injection drug product is extremely robust to challenging stress conditions that may occur during patient use of this multidose product for chronic administration.
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Brown H, Townsend M, Fearn S, Perry VH. The monoclonal antibody HB1 recognizes an adhesion molecule for macrophages in the brain. JOURNAL OF NEUROCYTOLOGY 1998; 27:867-76. [PMID: 10659679 DOI: 10.1023/a:1006932505819] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The brain environment exerts a powerful influence on macrophage phenotype, as exemplified by microglia, but the mechanisms mediating this control are nuclear. Since adhesion molecules are known to transmit signals across cell membranes, we investigated adhesion receptors involved in macrophage interaction with brain tissue. We have demonstrated previously that macrophages adhere specifically to CNS neurones in an in vitro assay. Here we show that this adhesion is inhibited by lectins, including Griffonia simplicofolia isolectin B4 (GSI), which has been used as a microglial marker for many years. Adhesion is unaffected by antibodies to several known adhesion molecules but is markedly inhibited by a new monoclonal antibody: HB1. HB1 recognizes microglia in the normal brain and activated microglia and recruited monocytes during CNS pathology. It labels a subset of resident macrophages and recruited monocytes in other tissues. Using this antibody, we isolated a protein of about 110 kDa from macrophage cell lysates. This protein is recognized by GSI, providing the first evidence of a functional role for the antigen labelled by this lectin. Further study of the HB1 antigen may provide important information about the influence of the brain environment on the phenotype of monocytic cells.
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