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Effets antalgiques des antidépresseurs monoaminergiques : de la dépression à la neuropathie : approche préclinique / Antinociceptive properties of monoaminergic antidepressants : from depression to neuropathy : Preclinical approachHache, Guillaume 20 June 2012 (has links)
Il existe une comorbidité entre douleur et dépression. Si les antidépresseurs inhibiteurs de recapture de monoamines représentent le traitement de première intention des troubles dépressifs unipolaires, certains d’entre eux sont également recommandés en première ligne de traitement des douleurs neuropathiques. L’objectif de ce travail a été d’étudier les propriétés analgésiques de ces antidépresseurs dans des modèles animaux co-exprimant des éléments de phénotypes douloureux et dépressifs. Pour cela nous avons développé des tests d’évaluation comportementale de la douleur chez la souris. Ces tests permettent de décrire la sensibilité douloureuse des animaux et d’évaluer les effets pharmacologiques de substances de référence et innovantes.Nous avons ainsi démontré que la fluoxétine, inhibiteur sélectif de la recapture de sérotonine (ISRS), possède des effets antalgiques sur les altérations de sensibilité d’un modèle d’anxiété/dépression chez la souris : le modèle CORT. La caractérisation d’un phénotype douloureux chronique chez ces souris renforce la pertinence de ce modèle neuropsychopharmacologique, puisqu’il exprime une des comorbidités fréquentes des pathologies dépressives. De plus, l’efficacité antalgique de la fluoxétine dans ce modèle plaide en faveur d’une modulation de la composante affective de la douleur par les ISRS.De plus, nous avons caractérisé l’effet antalgique d’une nouvelle classe d’antidépresseurs monoaminergiques, les triples inhibiteurs de recapture des monoamines capables d’augmenter à la fois les concentrations intracérébrales de sérotonine, noradrénaline et dopamine. Pour ce faire, nous avons développé un modèle de douleurs induites par injections répétées d’oxaliplatine chez la souris et comparé l’efficacité de différents traitements sur ces douleurs. Les souris « oxaliplatine » développent une hyperalgie mécanique, ainsi qu’une allodynie et hyperalgie au froid. Ces altérations de la sensibilité douloureuse sont corrigées par l’administration aigüe d’un triple bloqueur (indatraline) en faisant intervenir des mécanismes probablement supra-spinaux. La composante dopaminergique de ces substances apporte un intérêt dans le profil antalgique. Par ailleurs, les souris « oxaliplatine » développent des traits caractéristiques d’un phénotype anxio-dépressif et l’indatraline semble avoir des effets antidépresseurs dans ce modèle, ouvrant la possibilité d’une participation de la DA à la composante affective de la douleur et plus d’effets sur l’influx somatosensoriel. L’ensemble de nos travaux fait ressortir l’importance du développement et de l’utilisation de modèles animaux co-exprimant douleurs et anxiété/dépression afin de mieux définir les mécanismes liant ces pathologies et d’optimiser les critères de développement des futurs antidépresseurs et analgésiques. / High comorbidity is described between depression and pain disorders. Monoaminergic reuptake inhibitors represent the first choice of treatment for depression and serotonin and norepinephrin reuptake inhibitors are also recommended for the treatment of neuropathic pain disorders. We aims at evaluating analgesic effects of these drugs in animal models sharing anxio-depressive and painful phenotype. We first developed tests to assess pain sensitivity in mice and analgesic properties of pharmacological compounds. Depressive phenotype was assessed using various behavioural paradigms of anxiety/depression.We thus show that fluoxetine, a selective serotonin reuptake inhibitor (SSRI), provide antinociceptive effects in a mice model of anxiety-depression: the CORT model. Fluoxetine may thus exert its analgesic effect by modulating the affective aspect of pain in addition to a putative influence on sensory mechanisms. Moreover we characterized analgesic effects of a new generation of antidepressant, the triple reuptake inhibitors, which simultaneously potentialisate serotoninergic, noradrenergic and dopaminergic neurotransmission, in a mice model of oxaliplatin-induced neuropathy. Our results support that indatraline provide a better analgesic profile than escitalopram and venlafaxine in pain relief in oxaliplatin-treated mice. Although other investigations are required to quantify the putative involvement of DA in the therapeutic action of indatraline, the benefit can be attributed to this additional component. Indeed, reinforcement of descending control pathways though 5-HT and NE systems has been proposed to participate in the analgesic properties of dual reuptake inhibitors. The fact that indatraline was able to enhance dopaminergic transmission in the Anterior Cingulate Cortex argues in favor of a more potent action upon this inhibitory descending control of pain. Results with indatraline in the depression paradigm cannot rule out the possibility that the antidepressant property of the TRI accounts for its analgesic effect.This work provides a support for the need of animal models sharing anxio/depressive and painful phenotype in order to define mechanism responsible for such co-mobidity and optimize the development of newer antidepressants and pain killers.
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Role of Gigaxonin in the Regulation of Intermediate Filaments: a Study Using Giant Axonal Neuropathy Patient-Derived Induced Pluripotent Stem Cell-Motor NeuronsJohnson-Kerner, Bethany January 2013 (has links)
Patients with giant axonal neuropathy (GAN) exhibit loss of motor and sensory function and typically live for less than 30 years. GAN is caused by autosomal recessive mutations leading to low levels of gigaxonin, a ubiquitously-expressed cytoplasmic protein whose cellular roles are poorly understood. GAN pathology is characterized by aggregates of intermediate filaments (IFs) in multiple tissues. Disorganization of the neuronal intermediate filament (nIF) network is a feature of several neurodegenerative disorders, including amyotrophic lateral sclerosis, Parkinson's disease and axonal Charcot-Marie-Tooth disease. In GAN such changes are often striking: peripheral nerve biopsies show enlarged axons with accumulations of neurofilaments; so called "giant axons." Interestingly, IFs also accumulate in other cell types in patients. These include desmin in muscle fibers, GFAP (glial fibrillary acidic protein) in astrocytes, and vimentin in multiple cell types including primary cultures of biopsied fibroblasts. These findings suggest that gigaxonin may be a master regulator of IFs, and understanding its function(s) could shed light on GAN as well as the numerous other diseases in which IFs accumulate. However, an interaction between gigaxonin and IFs has not been detected and how IF accumulation is triggered in the absence of functional gigaxonin has not been determined. To address these questions I undertook a proteomic screen to identify the normal binding partners of gigaxonin. Prominent among them were several classes of IFs, including the neurofilament subunits whose accumulation leads to the axonal swellings for which GAN is named. Strikingly, human motor neurons (MNs) differentiated from GAN iPSCs recapitulate this key phenotype. Accumulation of nIFs can be rescued by reintroduction of gigaxonin, by viral delivery or genetic correction. GAN iPS-MNs do not display survival vulnerability in the presence of trophic factors, but do display increased cell death in the presence of oxidative stress. Preliminary experiments suggest that in iPS-MNs nIFs are degraded by contributions from both the proteasome and lysosome. Gigaxonin interacts with the autophagy protein p62 which has been implicated in the clearance of ubiquitin aggregates by the lysosome, and this interaction is greatly enhanced in conditions of oxidative stress. My data provide the first direct link between gigaxonin loss and IF aggregation, and suggest that gigaxonin may be a substrate adaptor for the degradation of IFs by autophagy, pointing to future approaches for reversing the phenotype in human patients.
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Aspectos clínico-neurológicos da neuropatia motora multifocal / Clinical neurological aspects of multifocal motor neuropathyLourenço, Paula Marques 11 July 2016 (has links)
A neuropatia motora multifocal (NMM) é uma neuropatia inflamatória de baixa prevalência, 0,6/100.000 pacientes, caracterizada por uma fraqueza muscular progressiva, assimétrica e distal, sem comprometimento sensitivo. A NMM pode mimetizar a esclerose lateral amiotrófica (ELA), outras variantes da doença do neurônio motor e outras polineuropatias inflamatórias desmielinizantes crônicas, com início assimétrico. A diferenciação é importante, tendo em vista as especificidades da evolução e do tratamento das referidas neuropatias. O principal achado eletrofisiológico é o bloqueio de condução nervosa na ausência de anormalidades sensitivas. A fisiopatogenia da NMM é pouco conhecida. O frequente achado de anticorpos circulantes contra o monoassialogangliosídeo (GM1) é sugestivo de que possa haver seu comprometimento em alterações estruturais nodais e perinodais, com comprometimento multifocal da condução nervosa. O corolário desses distúrbios são paresias e paralisias, também de distribuição multifocal. A Imunoglobulina humana por via endovenosa em altas doses constitui o tratamento de escolha. Novas estratégias de tratamento alternativas são necessárias para prevenir fraqueza muscular permanente e incapacidade. Poucos estudos e revisões bibliográficas têm elucidado as características clínicas da NMM, com a ausência na literatura de publicações de série de casos nacionais. No presente estudo, a partir de uma revisão retrospectiva, serão avaliados os aspectos clínicos- eletrofisiológicos da NMM, a fim de se obter um maior entendimento da evolução da doença. / The multifocal motor neuropathy (MMN) is an inflammatory neuropathy that has low prevalence (0.6 / 100,000 patients). It is characterized by progressive, asymmetric and distal muscle weakness without sensory impairment. The MMN can mimic amyotrophic lateral sclerosis (ALS), other motor neuron disease variants and other chronic inflammatory demyelinating polyneuropathy, with asymmetric start. Differentiation is important, given the specificities of the development and treatment of these neuropathies. The main electrophysiological finding is the nerve conduction block in the absence of sensory abnormalities. The pathophysiology of MMN is little known. The frequent finding of circulating antibodies against monoassialogangliosides (GM1) is suggestive that there may be their involvement in nodal and perinodal structural changes with multifocal impairment of nerve conduction. The corollary of these disorders is paresis and paralysis, with also multifocal distribution. The human immunoglobulin intravenously in high doses constitutes the treatment of choice. New alternative treatment strategies are needed to prevent permanent muscle weakness and disability. Few studies and literature reviews have elucidated the clinical features of MMN and there are no case series publications in the national literature. In this study, from a retrospective review, will be assessed clinic and electrophysiological features of MMN in order to obtain a greater understanding of disease progression.
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Matrix metalloproteinases and experimental diabetic neuropathyDriscoll, Heather January 2011 (has links)
Diabetic symmetrical polyneuropathy is the most common secondary complication of diabetes, with no effective treatment, apart from maintaining tight glycemic control. It is therefore essential to understand the mechanisms underlying the pathogenesis of the disease in order to develop new therapeutic strategies. Biochemical and structural changes are observed in the extracellular matrix (ECM) of the peripheral nerve in diabetes: including increased endoneurial collagen; reduplication of basement membranes around endoneurial capillaries; a thickening of basal lamina; and accumulation of advanced glycation end-products (AGEs). In normal nerves, ischaemic or other damage to distal axons provokes a regenerative response; in diabetes this is abortive and failure of axonal regeneration is a hallmark of clinical and experimental diabetic neuropathy. Matrix metalloproteinases (MMPs) are a large family of zinc-dependent proteolytic enzymes that cleave the protein components of the ECM. MMP-2 and MMP-9 play a central role in Wallerian degeneration and regeneration following nerve injury. This thesis investigates whether MMP-2 and -9 expression and/or activity were altered in the peripheral nerve in diabetes, and could contribute to regenerative failure in diabetic neuropathy. Using an experimental model of diabetes, we have demonstrated that MMP-2, but not MMP-9, is upregulated at gene, protein and activity levels in the rat sciatic nerve 8 weeks post-streptozotocin (STZ). This upregulation was not maintained at later time-points of diabetes. In vitro sciatic nerve cryoculture studies showed that peripheral nerve from STZ-diabetic rats was less supportive for neurite outgrowth from dissociated adult rat sensory neurons than nerve obtained from age-matched control rats. Cyrocultures were pre-treated with either MMP-2 or chondroitinase ABC, remodelling the peripheral nerve ECM, via the removal of inhibitory chondroitin sulfate proteoglycans from the sciatic nerve, and significantly enhanced its ability to support axonal regeneration, and partially restored the diabetes-associated regenerative deficit. However, exogenous MMP-2 or MMP-9 did not directly affect neurite outgrowth of dissociated adult rat sensory neurons. Finally, we assessed the neuroprotective effects of the AGE inhibitors LR90 and pyridoxamine in experimental diabetes, using a number of electrophysiological, behavioural and biochemical endpoints. These inhibitors were effective at preventing the development of some of the functional deficits observed in STZ-diabetes. Sensory nerve conduction velocity deficits and lipid peroxidation in the sciatic nerve were prevented by both LR90 and pyridoxamine. These agents have potential for the treatment of diabetic neuropathy.
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Assessment of novel, non-invasive interventions for the prevention of foot ulceration in patients with diabetes and a mechanistic study of progenitor cells from diabetic patientsBin Hasan, Ahmad Najib January 2018 (has links)
Diabetic foot ulceration (DFU) is a known major complication of diabetes mellitus which contributes to lower extremities amputation. This study aimed to investigate the use of interventional devices either as a preventative or therapeutic strategy to improve clinical management of this pathology, as well as investigating the impaired function of endothelial progenitor cells in the diabetic condition. The first element targeted plantar callus formation among diabetic neuropathic (NRP) patients through the use of a SurroSenseRxTM biofeedback device. Reducing foot pressure with improved walking strategy in the 6 months study in diabetic neuropathy patients (n=20) appeared to minimise the size of non-ulcerative plantar callus (p < 0.05), potentially reducing future ulcer recurrence. The 2nd study focused on the use of a GekoTM electrical stimulation device to enhance DFU healing in 24 patients. Wounds were characterised as being neuroischaemic (NRI) or neuropathic (NRP) based on standard parameters adopted in the Manchester diabetes clinic. The device was worn by 11 intervention subjects and compared to 13 controls without any electrical stimulus. Results suggested healing and wound closure have potentially increased in participants with electrical stimulation. In addition, Neuropathy Disability Score (NDS) was improved among intervention patients compared to control (p < 0.0001). The 3rd, in vitro and mechanistic study focuses on the outgrowth of endothelial cells (OECs), abnormal angiogenic responses and inflammatory microenvironment which could contribute to impaired wound healing in diabetic patients. OECs were isolated from diabetic patients and healthy controls (HCs), characterised by immunohistochemistry and Polymerase Chain Reaction (PCR). The functions of the three OEC groups from NRI, NRP diabetic patients and healthy controls respectively were compared using in vitro proliferation, transwell migration and wound healing scratch assays, together with matrigel tube formation assays. Scratch assays showed 100% closure in HCs over 24 hours, while 86.6% closure was apparent in NRI vs 38.1% in NRP. Seahorse mitochondrial stress test was conducted and demonstrated mitochondrial dysfunction in NRP vs NRI vs HCs (p < 0.05). Western blot analysis showed a lack of ERK phosphorylation by NRP OECs and an up-regulation of plasma inflammatory cytokines (TNFa and IL-6) in diabetic samples vs HC (p < 0.0001), while the angiogenic factors ang-2, FGF-2, VEGF-D, HGF and IL-8, and nitric oxide bioavailability were all significantly reduced in diabetic samples vs HC (p < 0.05). The functional defects of the diabetic OECs were partially restored through glycomimetic (synthesis compounds for endothelial damage protection) treatment (p < 0.05). In summary, this study has highlighted areas worthy of future development both in terms of preventative and therapeutic strategies. With improvements in digital technology and the need to empower patients to take responsibility of their health and well-being as well as greater understanding of the cellular and molecular biological repair processes that may be exploited, there may be potentials to reduce the risk of future ulceration among patients using these novel approaches in the future.
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Investigating Chemotherapy Induced Peripheral Neuropathy (CIPN) and its treatment, using functional Magnetic Resonance Imaging (fMRI)Seretny, Marta January 2017 (has links)
Background: Chemotherapy Induced Peripheral Neuropathy (CIPN) is a debilitating neuropathy caused by commonly used chemotherapeutics. Clinically, the problem of CIPN is compounded by difficulties with diagnosis and limited treatment options. The pathophysiology of CIPN remains elusive, with current mechanistic postulates focused mainly on the peripheral nervous system. However, animal and human models of non-CIPN neuropathic conditions have shown the brain to be central to the development and maintenance of painful neuropathy. Moreover, evidence suggests that aberrant activity in key regions of the brain and brainstem could denote individual vulnerability for chronic pain states. The impact of the brain on CIPN development is unknown. Assessment of drug efficacy using brain imaging can provide sensitive readouts and is increasingly used in clinical trials. Aims: Firstly, to prospectively explore the structure and function of the brain in cancer patients prior to chemotherapy administration, using functional magnetic resonance imaging (fMRI), in order to determine whether baseline differences exist between patients who progress to CIPN as compared to those who do not. Secondly, to develop a pilot study using fMRI to investigate a topical treatment for CIPN, in order to assess the feasibility of setting up a study with this kind of design. Methods: To address the first aim of this thesis a prospective cohort study (the CIPN fMRI Study) was developed. Cancer patients scheduled to receive neurotoxic chemotherapy treatment including oxaliplatin, carboplatin, carbotaxol, or cisplatin, were recruited from three NHS trusts in Scotland, to undergo a high resolution (3 tesla) functional MRI scan, at a single time point prior to commencement of chemotherapy. During the scan structural, resting state and functional data were collected. Functional data involved the presentation of punctate stimuli (using a 256mN von Frey filament), above the patients’ right medial malleolus. While receiving the punctate stimuli, patients viewed images that had neutral or positive emotional content or a baseline coloured image with no content. Sample size was based on previously successful pain fMRI studies and pragmatic estimates. Acute CIPN was defined clinically by common toxicity criteria as necessitating a chemotherapy dose reduction or cessation. Data were analysed using FMRIB’s Software Library (FSL) version 5, 2015. Standard data pre-processing (brain extraction, registration, B0 unwarping, motion correction, and denosiing with FIX) was carried out. Structural analysis was conducted using FIRST. Resting state analysis utilised FSL’s MELODIC tool, and a non-parametric group comparison was made following a dual regression approach. FEAT was used for both first and second level functional analyses. Group comparisons were made using a mixed effects analysis (z threshold 2·3 and 2, regions considered significant at p < 0·05, cluster corrected). The group was split by sex to explore known sex differences in pain processing. To address the second aim of this thesis, a pilot fMRI randomised controlled trial (MINT3 Study) was designed. Approvals from ethics and research and development were sought and obtained. Data collection forms were developed. An fMRI experiment was proposed and a single pilot scan was conducted and analysed. Results: 30 patients were recruited for the CIPN fMRI study (mean age 60·4 years, 95% Confidence Interval: 57.4-63.4, 17 women). Two patients had lung cancer, nine had gynecological malignancies and 18 had colorectal cancer. 17 patients developed acute CIPN. Structural analysis showed that patients who developed CIPN had a smaller volume of the Nucleus Accumbens (NAc). Resting state analysis did not show clear differences between those who developed CIPN and those who did not. Finally, functional analysis showed that patients who did not develop CIPN had greater activation in the superior frontal gyrus when viewing positive emotional images as compared to those who did progress to CIPN. Region of interest analysis showed that female patients who developed CIPN had greater activity in their mesencephalic pontine reticular formation (MPRF). Male patients who progressed to CIPN had decreased activity in their thalamus. Feasability of the MINT3 study set up and fMRI paradigm was assessed. Interpretation Differences in brain structure and function are evident between patients who developed CIPN and those who did not. Crucially, the regions identified, in particular the NAc, have been postulated to denote a vulnerability for progression to pain states. Although the findings need further confirmation they suggest a paradigm shift in terms of CIPN as a clinical problem. Specifically, it appears that certain individuals can be considered as having increased risk of CIPN development prior to chemotherapy administration. This risk relates to the baseline structure, and function of their brains. Finally, the set up of the MINT3 fMRI study showed that this kind of study design is acceptable in terms of ethical and R&D approvals and a single healthy volunteer pilot.
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Intoxicação Espontânea pelo Herbicida Clomazone em Ovinos e Reprodução Experimental da Enfermidade / Spontaneous Poisoning by Clomazone Herbicide in Sheep and Experimental Reproduction Of DiseaseFagundes, Maurício Zacharias 09 August 2013 (has links)
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Previous issue date: 2013-08-09 / As neuropatias tóxicas em animais de produção causadas por pesticidas correspondem a um importante grupo de enfermidades degenerativas do sistema nervoso central e periférico. No entanto, pouco se conhece sobre os reais impactos tóxicos de muitos desses produtos em animais e humanos e ao meio ambiente. O clomazone é um herbicida amplamente utilizado na região sul do Brasil por ser potente e supostamente seguro, com baixa toxicidade para animais e humanos. Até o presente não há relatos da intoxicação por esse herbicida em animais domésticos. O presente trabalho relata a intoxicação espontânea e experimental por clomazone em ovinos. De um rebanho com 103 ovinos, 20 animais apresentaram especialmente sinais clínicos neurológicos e respiratórios. A intoxicação foi reproduzida experimentalmente em três ovinos com a administração de 134 mg/kg de peso corporal de clomazone. Tanto nos casos naturais como experimentais o sinais clínicos incluíram taquipnéia, anorexia, apatia e dificuldade de locomoção com debilidade em membros torácicos e pélvicos, além de arrastar de pinças. Macroscopicamente não foram observadas alterações significativas. Microscopicamente, foram observadas especialmente vacuolização em substância branca e alguns vacúolos perineuronais e congestão de vasos das leptomeninges e do neurópilo. Ultraestruturalmente, as alterações vacuolares caracterizaram-se especialmente por tumefação em dendritos e processos astrocitários. A partir dos dados obtidos conclui-se que o clomazone é um agente tóxico capaz de causar neuropatia tóxica em ovinos. / The toxic neuropathies in farm animals caused by pesticides represent an important group of degenerative diseases of the central and peripheral nervous system. However, little is known about the real impact of many of these toxic products on animals and humans and to the environment. The clomazone is a herbicide that has been widely used in southern Brazil and includes one of the most potent herbicides and supposedly safe, with low toxicity to animals and humans. To date, there are no reports of this herbicide poisoning in domestic animals. This study describes the spontaneous and experimental poisoning due to clomazone herbicide in sheep. In a flock of 103 sheep, approximately 20 showed clinical signs especially neurological and respiratory.
The poisoning was experimentally reproduced in three sheep with the administration of 134mg/kg body weight of clomazone. Both in natural and experimental cases the clinical signs included tachypnea, anorexia, apathy and limited mobility with weakness in forelimbs and hind limbs, drag tweezers, and gait changes. Macroscopically, there were no significant changes. Microscopically, were observed especially vacuolization in
the white matter of brain, perineuronal vacuoles and, hyperemia congestion of the leptomeningeal and neuropil vessels. Ultrastructurally, the vacuolar lesions in the brain correspond to dendritic and astrocytic processes swelling. From the data obtained it was concluded that the clomazone is a toxic agent capable of causing toxic neuropathy in sheep.
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Translational approach to the characterisation, early identification and treatment of chemotherapy-induced peripheral neuropathyRamnarine, Sabrina January 2017 (has links)
Background Chemotherapy-induced peripheral neuropathy (CIPN) is a common dose-limiting toxicity with significant sequelae impacting prognosis and quality of life. The natural history and pathophysiological mechanisms of CIPN are unclear. Equally, the lack of systematic approach to diagnosis and assessments contribute to difficulty identifying at risk patients with implications on symptom burden. Effective management of CIPN is also difficult due to limited treatment options. To try and address this challenging clinical problem, this thesis aimed to adopt a translational approach to: 1) characterisation and early identification of the development of CIPN in cancer patients receiving neurotoxic chemotherapy and 2) explore topical treatment options in patients with chronic peripheral neuropathic pain. Methodology In the CIPN study, a mixed cohort of colorectal, gynaecological and lung cancer patients receiving neurotoxic chemotherapy (platinum agents and taxanes) were assessed prospectively, at baseline (prior to initiating chemotherapy), during cycles (every 3 weeks) and post-treatment (every 3 months) for up to 12 months (cumulative 261 assessments). Comprehensive longitudinal clinical characterisation consisted of the integration of quantitative sensory testing (QST), objective measure of function (grooved pegboard test), patient-reported outcomes and in vivo confocal microscopy to provide insight into the clinical course and potential psychophysical biomarkers of CIPN during and after chemotherapy. In the pilot intervention study, patients with chronic, complex cancer treatment related peripheral neuropathic pain received a single application of high concentration 8% capsaicin patch. Assessments conducted at baseline, 4 weeks and 12 weeks included patient-reported outcomes and QST with an exploratory application of in vivo confocal microscopy in a case. Results In the CIPN study, 33 patients when compared to 33 age and gender matched healthy controls displayed thermal hyperalgesia, sensorimotor impairment and increased resting heart rate prior to initiating neurotoxic chemotherapy. Characterisation of somato-sensory profile demonstrated dysfunction of the various types of primary afferent nerves (Aβ, Aδ and C). Assessing the change over time from baseline to during cycles and post-treatment follow up, revealed signs and symptoms as early as cycle 2 with an increase in the later cycles and 3 months post-treatment follow up. A greater burden was observed at 12 months in comparison to baseline. Significant changes were observed in QST parameters indicating both small and large fibre deficits. Interesting associations were observed for example with tactile deficits in the upper and lower limb and patient-reported outcomes. The repeated measures model provided an opportunity to distil the relationship between subjective and objective measures of CIPN. The subclinical findings at baseline however did not translate to obvious predictors of CIPN development. The exploratory use of in vivo confocal microscopy (45 healthy controls, 9 patients) demonstrated correlation with current assessment tools (QST). Analysis from the pilot intervention study of 20 patients revealed clinically significant improvement in pain in a subset at 4 and 12 weeks post-treatment. Conclusion Overall the combination of subjective and objective measures utilised in the prospective characterisation of this mixed cohort of cancer patients provided a useful paradigm for qualifying and quantifying the trajectory of CIPN related peripheral nerve damage and symptom burden with additional contribution from the novel in vivo confocal microscopy work. In capturing the varied spectrum of phenotypes, this approach may provide insight into the complexities of the underlying neurobiological mechanisms. The baseline subclinical sensory, motor and autonomic nerve dysfunction implicate a cancer-mediated process possibly contributing to CIPN. Although the preliminary investigation of baseline predictors of CIPN was inconclusive, thermal pain threshold warrant further investigation. These findings highlight the need to further address prediction and risk stratification in larger studies. The exploratory intervention study suggests that patients with chronic neuropathic pain may receive some benefit in pain severity, function and mood with effect continuing at 12 weeks post-treatment. This research warrants further investigation in larger cohorts.
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Influência da palmilha (plataforma para tarso) no equilíbrio do paciente com hanseníase e alteração de sensibilidade / Influence of the insole (platform for tarsus) in the body balance control of the leprosy patient with sensitivity impairmentRached, Thania Loiola Cordeiro Abi 14 December 2015 (has links)
A hanseníase é doença crônica causada pelo Mycobaterium leprae e possui como característica a alteração de sensibilidade cutânea, causando deformidades de mãos e pés. O tratamento compreende o uso de medicamentos (PQT) e o Ministério da Saúde (MS) preconiza o uso de palmilhas tipo Plataforma para Tarso (PT) como tratamento complementar. Há na literatura muitos artigos sobre o uso de palmilhas para melhora do equilíbrio e redistribuição da pressão plantar em pacientes neuropáticos, mas não foram encontrados estudos que incluíssem as palmilhas PT. Neste estudo comparou-se o equilíbrio do paciente hanseniano com valores de normalidade pré-definidos e também comparou-se prospectivamente a influência da palmilha PT no paciente com hanseníase, por meio de testes de equilíbrio estático e dinâmico realizados com o aparelho Balance Master (NeuroCom Int. Inc.) antes e após 3 meses de uso. Foram selecionados 40 pacientes em tratamento no HCFMRP, dos quais 19 mantiveram o seguimento à pesquisa (68,4% do sexo masculino, com média etária de 51,95), e todos com mesma classificação operacional Multibacilar. Os testes delinearam o comportamento destes pacientes com relação aos controles involuntário de equilíbrio (sistemas sensoriais-teste modifCTSIB) e voluntário de excursão do Centro de Gravidade Corporal (COG; teste LOS), bem como a estabilidade da marcha (teste WA). Os resultados obtidos com o modifCTSIB mostraram que os pacientes com hanseníase, para o controle do equilíbrio (de acordo com a relação entre testes com olhos abertos e fechados, e para superfície estável e instável; valor p<0,01 para todas as correlações aplicadas), são mais dependentes do sistema visual que do somatossensorial, em relação à normalidade. As palmilhas PT não influenciaram na modulação dos sistemas sensoriais (p>0,05). No entanto o uso das palmilhas interferiu negativamente no teste LOS, para as variáveis distância final percorrida e máxima excursão do COG somente no ponto para frente e para esquerda (p<0,01), e favoreceu o controle direcional do COG no mesmo ponto (p=0,02). Na análise dos prontuários foram identificados déficits sensitivos com maior frequência nos antepés esquerdos. O teste WA revelou que os pacientes apresentaram a marcha mais lenta em relação ao padrão de normalidade, e aumentaram a velocidade de marcha (p=0,04) e o comprimento do passo (p=0,04) após o uso das palmilhas. Concluiu-se que as palmilhas tipo PT favoreceram a estabilidade para a marcha e para o controle voluntário do equilíbrio. E ainda foi observado que os pacientes tornaram-se dependentes das palmilhas, fator importante a ser considerado pelo serviço de Saúde após a alta medicamentosa / Leprosy is a chronic disease caused by the Mycobacterium leprae with sensitivity impairment as a characteristic that could lead to deformities of hands and feet. The Ministry of Health of Brazil (MS) recommends the use of platform for Tarsus (PT) insoles as a complementary treatment to the Multi-drug Therapy (MDT). Many articles in literature discussed the use of insoles for improving balance and redistribution of plantar pressure in neuropathic patients, but there are no studies that included PT insoles. This study compared the balance control values for the leprosy patient with normal standards and also prospectively compared the influence of PT insole in patients with leprosy, by means of static and dynamic tests performed with the Balance Master (NeuroCom Int. Inc.) device, before and after 3 months. 40 patients following treatment in HCFMRP were selected, of which 19 completed the follow-up to the survey (68.4% male, mean age 51.95), all classified operationally as Multibacillary. The tests outlined the behavior of these patients with regard to involuntary balance control (modifCTSIB sensory test) and voluntary excursion of the Body Center of Gravity (COG; LOS test) as well as the gait stability (WA test). The results obtained with the modifCTSIB showed that patients with leprosy are more dependent on the visual system than the somatosensation for balance controlwhen compared to normal values (according to the relationship between tests with open and closed eyes, and stable and unstable surface; p <0.01 for all applied correlations). The insoles PT did not influence the modulation of the sensory systems (p> 0.05). However the use of insoles interfered negatively in the LOS test for the variables end point and maximum excursion of the COG only on the forward to left position (p <0.01), and favored the directional control of COG at the same position (p= 0.02). The analysis of the patients file revealed that sensitivity deficits were identified more frequently in the left forefeet, which might explain the observed differences for the excursion of the COG only in this region. The WA test showed that patients have slower walking patters compared to normal values but had their walking speed (p = 0.04) and the length of their step increased (p = 0.04) after the use of the insoles. It was concluded that the PT insoles favored gait stability and voluntary control of body balance. It was also observed that patients become dependent on the insoles, an important factor to be considered by the Health service after the PQT discharge
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Investigating the Role of Nicotinic Acetylcholine Receptor Agonists in Lung Cancer Progression and Chemosensitivity in the Context of Treating Chemotherapy-Induced Peripheral NeuropathyKyte, Sarah L 01 January 2018 (has links)
While cancer chemotherapy continues to significantly contribute to the number of cancer survivors, exposure to these drugs can often result in chemotherapy-induced peripheral neuropathy (CIPN), a consequence of peripheral nerve fiber dysfunction or degeneration. CIPN is characterized by sensory symptoms in the hands and feet, such as numbness, burning, and allodynia, resulting in an overall decrease in quality of life. Paclitaxel (Taxol), a microtubule poison that is commonly used to treat breast, lung, and ovarian cancers, has been found to cause CIPN in 59-78% of cancer patients. There is currently no effective preventative or therapeutic treatment for this side effect, which can be a dose-limiting factor for chemotherapy or delay treatment. Our collaborators in the laboratory of Dr. M. Imad Damaj have shown that nicotine, a nicotinic acetylcholine receptor (nAChR) agonist, and R-47, an α7 nAChR silent agonist, can prevent and reverse paclitaxel-induced peripheral neuropathy in mice. With regard to cancer, this work demonstrates that nicotine and R-47 do not enhance A549 and H460 human non-small cell lung cancer cell viability, colony formation, or proliferation alone, and they do not attenuate paclitaxel-induced growth arrest, apoptosis, or DNA fragmentation. Most importantly, nicotine and R-47 do not increase the growth of A549 tumors or interfere with the antitumor activity of paclitaxel in tumor-bearing mice. These data suggest that targeting nAChRs may be a safe and efficacious approach for the prevention and treatment of CIPN in cancer patients.
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