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Degutis G, Pobedinskas P, Boyen HG, Dexters W, Janssen W, Drijkoningen S, Hardy A, Haenen K, Van Bael M. Improved nanodiamond seeding on chromium by surface plasma pretreatment. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hardy A, Mason K, Harding L. Assessing health related quality of life before and one year after tonsillectomy, using the paediatric throat disorder outcome tool (T14). Int J Surg 2015. [DOI: 10.1016/j.ijsu.2015.07.242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Roche N, Boudarham J, Hardy A, Bonnyaud C, Bensmail B. Use of gait parameters to predict the effectiveness of botulinum toxin injection in the spastic rectus femoris muscle of stroke patients with stiff knee gait. Eur J Phys Rehabil Med 2015; 51:361-370. [PMID: 25213306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND Botulinum toxin type A (BTX-A) injection in the rectus femoris (RF) is commonly used to treat decreased peak knee flexion in swing phase of the gait in hemiplegic patients. However, the effect of BTX-A varies between 5° to 10° depending on the studies. Peak knee flexion also increases during fast gait and could constitute a way to predict the effect of BTX-A injection in the RF. AIM To determine if changes in gait parameters during fast gait before injection could predict the effect of RF BTX-A injection on peak knee flexion in hemiplegic patients. DESIGN Prospective observational study. SETTING A neurological rehabilitation department in a university hospital POPULATION Twenty two hemiplegic patients with stiff knee gait mainly due to spasticity of the RF and treated by RF-BTX-A-injection. METHODS Patients' gait was analyzed using a 3D motion analysis system and force plates. The gait recordings were performed before (PRE-RF-BTX-A:spontaneous and fast gait speed) and one month after RF-BTX-A-injection (POST-RF-BTX-A:spontaneous gait speed). Correlations between the percentage change in gait parameters during fast gait before RF-BTX-A-injection and the percentage increase in peak knee flexion POST-RF-BTX-A injection at spontaneous speed were analyzed. RESULTS The percentage improvement in peak knee flexion in the fast gait condition before injection was the only parameter correlated with the percentage increase in peak knee flexion POST-RF-BTX-A injection. This was confirmed by a stepwise linear regression. The percentage increase in peak knee flexion POST-RF-BTX-A injection was also correlated with the percentage increase in knee flexion angular velocity at toe-off in the fast gait condition. CONCLUSION The percentage increase in peak knee flexion in swing during fast gait before injection is a useful predictor of the increase in peak knee flexion following RF BTX-A injection in chronic stroke patients with RF spasticity. CLINICAL REHABILITATION IMPACT In stroke patients with SKG which is mainly caused by spasticity of the RF muscle, evaluating changes which occur during fast gait might help the therapist to identify patients who would benefit the most from BTX-A injection in the RF muscle.
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Hardy A, Dorne JLCM, Aiassa E, Alexander J, Bottex B, Chaudhry Q, Germini A, Nørrung B, Schlatter J, Verloo D, Robinson T. Editorial: Increasing robustness, transparency and openness of scientific assessments. EFSA J 2015. [DOI: 10.2903/j.efsa.2015.e13031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Hardy A, Thiong'o MW, Leroy A, Hardy P, Laporte C. Cleidocranial dysplasia with bilateral posterior glenohumeral dislocation: a case-report. Orthop Traumatol Surg Res 2015; 101:119-22. [PMID: 25592053 DOI: 10.1016/j.otsr.2014.11.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Revised: 09/29/2014] [Accepted: 11/14/2014] [Indexed: 02/02/2023]
Abstract
A 31-year-old man experienced bilateral posterior glenohumeral dislocation during seizures. He had cleidocranial dysplasia with complete absence of both clavicles. Cleidocranial dysplasia is a rare inherited disease also known as Marie-Sainton syndrome and responsible for dental abnormalities well-known to stomatologists and dentists. Other manifestations include defective development of the skull bones and hypoplastic or aplastic clavicles. We found no previous reports of bilateral posterior glenohumeral dislocation in patients with cleidocranial dysplasia. The objective of this work was to look for an association between clavicular aplasia and posterior glenohumeral dislocation.
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Abstract
INTRODUCTION Although the acute thrombosis and strangulation of haemorrhoids is a common condition, there is no consensus as to its most effective treatment. METHODS A PubMed search was undertaken for papers describing the aetiology and treatment of the acute complications of haemorrhoids. RESULTS The anatomy and treatments for strangulated internal haemorrhoids and thrombosed perianal varices are discussed. Studies of the effectiveness and complications of conservative and operative treatments are reviewed. CONCLUSIONS Ambiguities exist in the terminology used to describe the two separate pathologies that make up the acute complications of haemorrhoids. These complications have traditionally been treated conservatively. There is evidence that early operative intervention for strangulated internal haemorrhoids is safe and effective. A suggested algorithm for treatment is given, based on the published literature.
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Hardy A, Hardy A. Mary Adams Hunter. Assoc Med J 2013. [DOI: 10.1136/bmj.f411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Tarasewicz E, Hardy A, Zelivianski S, Jeruss J. Impact of CDK4 Inhibition and Chemotherapy on Smad3 Action in Breast Cancer Cell Proliferation and Migration. J Surg Res 2012. [DOI: 10.1016/j.jss.2011.11.347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Tarasewicz E, Hardy A, Straehla J, Foucar C, Zelivianski S, Jeruss J. P2-02-06: Inhibition of CDK4 Phosphorylation of Smad3 Decreases Cyclin D Overexpressing Breast Cancer Cell Proliferation and Migration. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p2-02-06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Several aspects of breast cancer onset and disease progression have been linked to members of the TGFβ superfamily and their associated downstream signaling components, the Smads. Alterations in Smad signaling have been directly implicated in the dichotomous role of TGFβ in malignancy, enacting both tumor suppressant and tumor promoting behaviors in breast carcinogenesis. Our previous work characterized Smad3 as a tumor suppressor and found that Smad3 action is inhibited upon phosphorylation by cyclin D/CDK4 in breast cancer cells. Others have shown that CDK phosphorylation of Smad3 can affect cell motility. Based on these findings, we hypothesized that activation of CDK4 leads to phosphorylation and inhibition of Smad3, thus releasing cell cycle arrest and promoting cell proliferation and metastasis.
Methods: MCF7 parental and cyclin D overexpressing cells (MCF7 CD1) were treated with a CDK4 inhibitor alone or in combination with doxorubicin or paclitaxel and cell proliferation was determined using the MTS assay. MCF7 study cells were also transduced with lentiviral empty vector, wild-type (WT) Smad3, or Smad3 containing mutant CDK sites (T179V and 5M) resistant to inhibitory cyclin D/CDK phosphorylation. Stably transduced cells were plated in Matrigel 3-dimensional (3D) culture and treated with CDK4 inhibitor alone or with doxorubicin over a 12 day time course. Colony area was measured using MetaMorph software. Transwell migration and Matrigel invasion assays were used to determine the effect that transfection with Smad3 CDK phosphorylation site mutants or treatment with a CDK4 inhibitor had on highly metastatic cyclin D expressing MDA-MB-231 cells. Study wells were fixed/stained and the number of migrated or invaded cells was counted. Results: Treatment with the CDK4 inhibitor alone resulted in a growth inhibitory effect on proliferation of MCF7 parental and CD1 cells. Treatment with the CDK4 inhibitor in combination with chemotherapy resulted in the greatest inhibition of cell proliferation. In 3D culture, colonies formed by MCF7 study cells transduced with T179V or 5M Smad3 mutant constructs had smaller acinar size when compared with vector-transduced control cells. When compared to untreated cells, the MCF7 CD1 cells treated with CDK4 inhibitor or chemotherapy alone had smaller acinar size, with greatest decrease in size observed when the treatments were combined. Lastly, MDA-MB-231 cells transfected with the 5M Smad3 mutant construct, containing mutations in all 5 CDK phosphorylation sites, resulted in the greatest decrease in cell migration and invasion, when compared with cells transfected with both vector control or WT Smad3. Treatment of the MDA-MB-231 cells with the CDK4 inhibitor also resulted in a significant decrease in cell migration and invasion.
Conclusions: Mutation of CDK phosphorylation sites in the Smad3 construct or direct inhibition of CDK4 resulted in a decrease in breast cancer cell proliferation, 3D colony formation and cell migration and invasion. Treatment with the CDK4 inhibitor in combination with chemotherapy further augmented these results. Inhibition of CDK4 and restoration of Smad3 activity may have a role in the treatment of breast cancers overexpressing cyclin D.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-02-06.
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Elen K, Murariu M, Peeters R, Dubois P, Mullens J, Hardy A, Van Bael MK. Towards high-performance biopackaging: barrier and mechanical properties of dual-action polycaprolactone/zinc oxide nanocomposites. POLYM ADVAN TECHNOL 2011. [DOI: 10.1002/pat.2062] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Jourdain M, Hardy A, Desprez P, Coche R. Syndrome de takotsubo: à propos d’un cas. ANNALES FRANCAISES DE MEDECINE D URGENCE 2011. [DOI: 10.1007/s13341-010-0016-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Bar-Isaac C, Hardy A. The Diffraction of a One-dimensional Gaussian Beam by an Amplitude Sinusoidal Grating. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/713818692] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Boxall A, Hardy A, Beulke S, Boucard T, Burgin L, Falloon P, Haygarth P, Hutchinson T, Kovats S, Leonardi G, Levy L, Nichols G, Parsons S, Potts L, Stone D, Topp E, Turley D, Walsh K, Wellington E, Williams R. Impacts of climate change on indirect human exposure to pathogens and chemicals from agriculture. CIENCIA & SAUDE COLETIVA 2010; 15:743-56. [DOI: 10.1590/s1413-81232010000300017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 12/10/2008] [Indexed: 11/21/2022] Open
Abstract
Climate change is likely to affect the nature of pathogens/ chemicals in the environment and their fate and transport. We assess the implications of climate change for changes in human exposures to pathogens/chemicals in agricultural systems in the UK and discuss the effects on health impacts, using expert input and literature on climate change; health effects from exposure to pathogens/chemicals arising from agriculture; inputs of chemicals/pathogens to agricultural systems; and human exposure pathways for pathogens/chemicals in agricultural systems. We established the evidence base for health effects of chemicals/pathogens in the agricultural environment; determined the potential implications of climate change on chemical/pathogen inputs in agricultural systems; and explored the effects of climate change on environmental transport and fate of various contaminants. We merged data to assess the implications of climate change in terms of indirect human exposure to pathogens/chemicals in agricultural systems, and defined recommendations on future research and policy changes to manage adverse increases in risks.
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Girot M, Wiel E, Hardy A, Smith G, Pruvo JP, Leclerc X, Goldstein P. 249 Stroke network, stroke, intravenous thrombolysis, intra-hospital delay, imaging. BMJ Qual Saf 2010. [DOI: 10.1136/qshc.2010.041632.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
BACKGROUND Aptamers as inhibitors of proteins in therapeutic applications offer great advantages over their antibody counterparts and the promise to be developed into the next generation therapeutic agents. However, the control of aptamer intellectual property (IP) by two major players has made aptamers an area difficult to operate and often off-putting for academic and commercial organisations. Yet, their great potential is keeping aptamers at the research forefront, with one aptamer in the clinic and various at different stages of clinical trials. OBJECTIVE To provide a comprehensive review of the aptamer IP landscape and the issues associated with aptamer therapeutics against protein targets. METHODS Extensive review of the scientific and patent literature. CONCLUSIONS Following our experience in developing, patenting and commercialising our aptamers against MUC1 and an extensive review of the literature, we have identified a variety of issues pertaining to the development of aptamers against protein targets for therapeutic applications, their patenting and granting of patents, the original IP holders and their policy, as well as the current market and traits. Despite a slow start, aptamers have been developed against various therapeutic proteins and offer the promise of providing a novel generation of therapeutic entities with a variety of applications.
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Boxall ABA, Hardy A, Beulke S, Boucard T, Burgin L, Falloon PD, Haygarth PM, Hutchinson T, Kovats RS, Leonardi G, Levy LS, Nichols G, Parsons SA, Potts L, Stone D, Topp E, Turley DB, Walsh K, Wellington EMH, Williams RJ. Impacts of climate change on indirect human exposure to pathogens and chemicals from agriculture. ENVIRONMENTAL HEALTH PERSPECTIVES 2009; 117:508-14. [PMID: 19440487 PMCID: PMC2679592 DOI: 10.1289/ehp.0800084] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 12/10/2008] [Indexed: 05/02/2023]
Abstract
OBJECTIVE Climate change is likely to affect the nature of pathogens and chemicals in the environment and their fate and transport. Future risks of pathogens and chemicals could therefore be very different from those of today. In this review, we assess the implications of climate change for changes in human exposures to pathogens and chemicals in agricultural systems in the United Kingdom and discuss the subsequent effects on health impacts. DATA SOURCES In this review, we used expert input and considered literature on climate change; health effects resulting from exposure to pathogens and chemicals arising from agriculture; inputs of chemicals and pathogens to agricultural systems; and human exposure pathways for pathogens and chemicals in agricultural systems. DATA SYNTHESIS We established the current evidence base for health effects of chemicals and pathogens in the agricultural environment; determined the potential implications of climate change on chemical and pathogen inputs in agricultural systems; and explored the effects of climate change on environmental transport and fate of different contaminant types. We combined these data to assess the implications of climate change in terms of indirect human exposure to pathogens and chemicals in agricultural systems. We then developed recommendations on future research and policy changes to manage any adverse increases in risks. CONCLUSIONS Overall, climate change is likely to increase human exposures to agricultural contaminants. The magnitude of the increases will be highly dependent on the contaminant type. Risks from many pathogens and particulate and particle-associated contaminants could increase significantly. These increases in exposure can, however, be managed for the most part through targeted research and policy changes.
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Hammond A, Bryan J, Hardy A. Effects of a modular behavioural arthritis education programme: a pragmatic parallel-group randomized controlled trial. Rheumatology (Oxford) 2008; 47:1712-8. [DOI: 10.1093/rheumatology/ken380] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Gracie A, Freeman D, Green S, Garety PA, Kuipers E, Hardy A, Ray K, Dunn G, Bebbington P, Fowler D. The association between traumatic experience, paranoia and hallucinations: a test of the predictions of psychological models. Acta Psychiatr Scand 2007; 116:280-9. [PMID: 17803758 DOI: 10.1111/j.1600-0447.2007.01011.x] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE The current study investigated the relationship between trauma and predisposition to hallucinations and to paranoia in a non-clinical sample. METHOD A total of 228 students completed online measures of trauma, post traumatic stress disorder (PTSD), schematic beliefs, perceptual anomalies, and predisposition to hallucinations and paranoia. RESULTS Associations were found between negative schematic beliefs, PTSD and predisposition to both paranoia and hallucinations. PTSD reexperiencing-symptoms were most strongly associated with a predisposition to hallucinations. Negative beliefs about self and others were most strongly associated with a predisposition to paranoia. CONCLUSION The results provide support for the prediction that there may be two routes between trauma and predisposition to psychosis. Clear support was found for a link between trauma and psychosis mediated by negative beliefs about self and others. There may also be a direct association between re-experiencing symptoms and hallucinations.
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Achtenhagen M, Hardy A, Kapon E. Transverse-mode control in vertical-cavity surface-emitting lasers via a patterned phase aperture. APPLIED OPTICS 2006; 45:8999-9006. [PMID: 17119600 DOI: 10.1364/ao.45.008999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Transverse-mode discrimination in vertical-cavity surface-emitting lasers that contain a patterned phase aperture is analyzed numerically. The two lowest-order modes are calculated for different aperture shapes and sizes. They are then expanded in Laguerre-Gaussian modes to study the power distribution as well as their beam propagation factor. The mode selection depends on the aperture's size and degree of symmetry. The maximum value for the mode discrimination in the case of a specific phase aperture is determined, and an enhancement by a factor of 3, compared to the case without a phase aperture, is found.
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Kuipers E, Bebbington P, Dunn G, Fowler D, Freeman D, Watson P, Hardy A, Garety P. Influence of carer expressed emotion and affect on relapse in non-affective psychosis. Br J Psychiatry 2006; 188:173-9. [PMID: 16449706 DOI: 10.1192/bjp.bp.104.007294] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND High expressed emotion in carers predicts relapse in psychosis, but it is not known why this is so. In our cognitive model of psychosis, we postulated that the effect is mediated through affective changes. AIMS To investigate the relationships between carer expressed emotion, patients' symptoms and carer characteristics during a recent relapse of psychosis. METHOD A total of 86 patients and carers were investigated in a cross-sectional design. RESULTS Patients whose carers showed high expressed emotion had significantly higher levels of anxiety and depression, but not more psychotic symptoms or lower self-esteem. Linear regression showed that carers'critical comments predicted anxiety in patients. Critical comments were related to low carer self-esteem and avoidant coping strategies. Low carer self-esteem was also related to carer depression, stress and carer 'burden', and to low patient self-esteem. CONCLUSIONS Our hypothesis was partially supported. Carer criticism was associated with patient anxiety, low carer self-esteem and poor carer coping strategies. Family interventions should focus on improving these after a relapse of symptoms of psychosis.
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Chauvin C, Le Bouquin-Leneveu S, Hardy A, Haguet D, Orand JP, Sanders P. An original system for the continuous monitoring of antimicrobial use in poultry production in France. J Vet Pharmacol Ther 2005; 28:515-23. [PMID: 16343283 DOI: 10.1111/j.1365-2885.2005.00697.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Data collection at the flock level on a continuous basis, for antimicrobial use surveillance purposes, provides a complex challenge. Using existing on-farm records, produced as part of the regulations for meat inspection, a sampling scheme was implemented to collect on a simple, representative and continuous basis, the forms providing history of antimicrobial consumption of poultry flocks slaughtered in Brittany. Relational database-stored information provided by the forms includes treatment purpose, antimicrobial drug administered, age at treatment and treatment duration. The aim of this study was to collect information describing antimicrobial drug use quantitatively and qualitatively, by computing the frequency of antimicrobial use according to species, therapeutic class, treatment purpose, duration, and animal age at treatment. A study was carried out to check the validity of farmers' declarations. Examples of data and results are presented such as the relative importance of the different antimicrobial classes in relation to the live weight treated, which shows that beta-lactams and tetracyclines are the main classes used in broilers and turkeys respectively. Average bird weight at treatment was 0.5 kg for a broiler and 3 kg for a turkey. Nevertheless, several 'at-risk' periods could be identified. Initial results after 1 year of data collection showed that this surveillance system provides valid, detailed and useful data about antimicrobial drug use in poultry production at a low cost and with only a moderate time involvement.
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Abstract
A number of new surgical treatments have led to a reappraisal of haemorrhoid disease over the last few decades. Despite a range of treatment modalities, the options are limited in their effectiveness and can lead to a number of complications. An inadequate classification system based on appearance rather than symptoms makes the choice of appropriate therapy difficult. More recent techniques have led to a move away from surgical excision. However, further research is required to establish their precise indications and long-term efficacy.
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Hardy A, Palouzier-Paulignan B, Duchamp A, Royet JP, Duchamp-Viret P. 5-hydroxytryptamine action in the rat olfactory bulb: In vitro electrophysiological patch-clamp recordings of juxtaglomerular and mitral cells. Neuroscience 2005; 131:717-31. [PMID: 15730876 DOI: 10.1016/j.neuroscience.2004.10.034] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2004] [Indexed: 10/25/2022]
Abstract
The olfactory bulb, first relay of olfactory pathways, is densely innervated by serotoninergic centrifugal fibers originating from the raphe nuclei. Although serotonin innervation was reported to be involved in olfactory learning in mammals, the action of this neurotransmitter on its putative cellular targets has been never described through unitary recordings. This lack of data initiated the present study where the effects of 5HT on juxtaglomerular and mitral cells are analyzed using whole-cell recordings on olfactory bulb slices. Serotonin depolarizes 34% of 525 JG cells. A multivariate statistical analysis of juxtaglomerular cells characteristics shows that the serotonin responsive cell group can be individualized regarding their tonic discharge-mode in response to a direct current injection, their lower expression of hyperpolarization-activated cation current and their low membrane capacities. The use of ion channel blockers and ramp voltage protocol indicate that serotoninergic depolarization of juxtaglomerular cells may be due to a nonselective cation current with a reversal potential of -44 mV. Pharmacological tests with serotonin receptor antagonists and agonists reveal that 5HT action on juxtaglomerular cells would be mainly mediated by 5HT2C receptors. In mitral cells, serotonin acts on 49.1% of the 242 tested cells, inducing two types of responses. A first subset of mitral cells (26.8%, n=65) were hyperpolarized by serotonin. This response would be indirect and mediated by action of GABA on GABAA receptors since it was antagonized by bicuculline. The involved GABAergic neurons are hypothesized to be juxtaglomerular and granular cells, on which serotonin would act mainly via 5HT2C and via 5HT2A receptors respectively. The second subset of mitral cells (22.3%, n=54) were directly depolarized by serotonin acting through 5HT2A receptors. Our data on serotonin action on juxtaglomerular cells and mitral cells reveal a part of functional mechanisms whereby serotonin can act on olfactory bulb network. This is expected to enrich the understanding of its determining role in olfactory learning.
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Abstract
Salmonella was the archetypal food poisoning organism of the 20th century. It achieved a high public profile following the salmonella-in-eggs crisis of 1988-89, but by then had been the subject of public health concern and scientific interest for over a century. Early associated with animal foods, the advent of phage typing in the 1940s began to reveal the complexity of its environmental associations. This paper explores the story of salmonella as a continuing problem in epidemiology, microbiology and public health, in the food chain, and in the kitchen.
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