956 resultados para COMPENSATORY ENLARGEMENT
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OBJECTIVE: Although intracranial hypertension is one of the important prognostic factors after head injury, increased intracranial pressure (ICP) may also be observed in patients with favourable outcome. We have studied whether the value of ICP monitoring can be augmented by indices describing cerebrovascular pressure-reactivity and pressure-volume compensatory reserve derived from ICP and arterial blood pressure (ABP) waveforms. METHOD: 96 patients with intracranial hypertension were studied retrospectively: 57 with fatal outcome and 39 with favourable outcome. ABP and ICP waveforms were recorded. Indices of cerebrovascular reactivity (PRx) and cerebrospinal compensatory reserve (RAP) were calculated as moving correlation coefficients between slow waves of ABP and ICP, and between slow waves of ICP pulse amplitude and mean ICP, respectively. The magnitude of 'slow waves' was derived using ICP low-pass spectral filtration. RESULTS: The most significant difference was found in the magnitude of slow waves that was persistently higher in patients with a favourable outcome (p<0.00004). In patients who died ICP was significantly higher (p<0.0001) and cerebrovascular pressure-reactivity (described by PRx) was compromised (p<0.024). In the same patients, pressure-volume compensatory reserve showed a gradual deterioration over time with a sudden drop of RAP when ICP started to rise, suggesting an overlapping disruption of the vasomotor response. CONCLUSION: Indices derived from ICP waveform analysis can be helpful for the interpretation of progressive intracranial hypertension in patients after brain trauma.
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BACKGROUND: Heerfordt syndrome is rare and is characterized by fever, uveitis, parotid gland enlargement, and facial nerve palsy. We hereby present a case of Heerfordt syndrome with unilateral facial nerve palsy as a presentation of sarcoidosis. HISTORY AND SIGNS: A 29-year-old male patient from Sri Lanka presented with eye redness OU, blurred vision OD, fever, headache, night sweat, fatigue, and weight loss (5 kg over 1 month). Examination revealed mild anterior uveitis OU, mild vitritis OD, fundus whitish lesions OU, left otalgia, taste disorders, bilateral parotid gland enlargement, and left facial nerve palsy. Work-up for infection or tumour was negative. Chest computed tomography and transbronchial lymph node biopsy set the diagnosis of sarcoidosis. THERAPY AND OUTCOME: The patient recovered completely within 2 months under therapy with prednisone and azathioprine. One year after onset of treatment, no recurrence was noted. CONCLUSIONS: Heerfordt syndrome is a rare manifestation of neurosarcoidosis and has to be included in the differential diagnosis of facial nerve palsy.
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Visual perception of body motion is vital for everyday activities such as social interaction, motor learning or car driving. Tumors to the left lateral cerebellum impair visual perception of body motion. However, compensatory potential after cerebellar damage and underlying neural mechanisms remain unknown. In the present study, visual sensitivity to point-light body motion was psychophysically assessed in patient SL with dysplastic gangliocytoma (Lhermitte-Duclos disease) to the left cerebellum before and after neurosurgery, and in a group of healthy matched controls. Brain activity during processing of body motion was assessed by functional magnetic resonance imaging (MRI). Alterations in underlying cerebro-cerebellar circuitry were studied by psychophysiological interaction (PPI) analysis. Visual sensitivity to body motion in patient SL before neurosurgery was substantially lower than in controls, with significant improvement after neurosurgery. Functional MRI in patient SL revealed a similar pattern of cerebellar activation during biological motion processing as in healthy participants, but located more medially, in the left cerebellar lobules III and IX. As in normalcy, PPI analysis showed cerebellar communication with a region in the superior temporal sulcus, but located more anteriorly. The findings demonstrate a potential for recovery of visual body motion processing after cerebellar damage, likely mediated by topographic shifts within the corresponding cerebro-cerebellar circuitry induced by cerebellar reorganization. The outcome is of importance for further understanding of cerebellar plasticity and neural circuits underpinning visual social cognition.
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We investigated the short-term and sustained hormonal and renal effects of angiotensin II (Ang II) receptor blockade in normotensive healthy volunteers. Twenty-four subjects maintained on a fixed sodium diet were randomized to receive for 8 days a placebo or 10 or 50 mg doses of the Ang II antagonist irbesartan (SR 47436, BMS 186295) according to a double-blind, parallel group design. Plasma renin activity, plasma immunoreactive Ang II and aldosterone levels, blood pressure, renal hemodynamics, and urinary electrolyte excretion were measured for 8 hours after the first and eighth administration of each dose of irbesartan or placebo. Ang II receptor blockade with irbesartan induced a dose-dependent compensatory increase in plasma renin activity and plasma angiotensin levels and a significant decrease in plasma aldosterone levels. The compensatory rise in plasma renin activity and Ang II levels was more pronounced on day 8, reflecting a long duration of the blocking effect of irbesartan. Irbesartan induced small changes in blood pressure and did not significantly modify renal blood flow and glomerular filtration rate. However, a significant decrease in filtration fraction was observed during receptor blockade on days 1 and 8. The tubular effects of irbesartan were characterized by a dose-dependent increase in sodium and chloride excretions. Interestingly, the cumulative natriuretic response to Ang II receptor blockade was similar on days 1 and 8, suggesting that in these subjects, renal Ang II receptors are not blocked over 24 hours during repeated administration even though this antagonist has a long duration of action (t1/2 of 15 to 17 hours).(ABSTRACT TRUNCATED AT 250 WORDS)
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Cell motility is an essential process that depends on a coherent, cross-linked actin cytoskeleton that physically coordinates the actions of numerous structural and signaling molecules. The actin cross-linking protein, filamin (Fln), has been implicated in the support of three-dimensional cortical actin networks capable of both maintaining cellular integrity and withstanding large forces. Although numerous studies have examined cells lacking one of the multiple Fln isoforms, compensatory mechanisms can mask novel phenotypes only observable by further Fln depletion. Indeed, shRNA-mediated knockdown of FlnA in FlnB¿/¿ mouse embryonic fibroblasts (MEFs) causes a novel endoplasmic spreading deficiency as detected by endoplasmic reticulum markers. Microtubule (MT) extension rates are also decreased but not by peripheral actin flow, because this is also decreased in the Fln-depleted system. Additionally, Fln-depleted MEFs exhibit decreased adhesion stability that appears in increased ruffling of the cell edge, reduced adhesion size, transient traction forces, and decreased stress fibers. FlnA¿/¿ MEFs, but not FlnB¿/¿ MEFs, also show a moderate defect in endoplasm spreading, characterized by initial extension followed by abrupt retractions and stress fiber fracture. FlnA localizes to actin linkages surrounding the endoplasm, adhesions, and stress fibers. Thus we suggest that Flns have a major role in the maintenance of actin-based mechanical linkages that enable endoplasmic spreading and MT extension as well as sustained traction forces and mature focal adhesions.
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RESUME L'hyperammonémie est particulièrement toxique pour le cerveau des jeunes patients et entraîne une atrophie corticale, un élargissement des ventricules et des défauts de myélinisation, responsables de retards mentaux et développementaux. Les traitements actuels se limitent à diminuer le plus rapidement possible le taux d'ammoniaque dans l'organisme. L'utilisation de traitements neuroprotecteurs pendant les crises d'hyperammonémie permettrait de contrecarrer les effets neurologiques de l'ammoniaque et de prévenir l'apparition des troubles neurologiques. Au cours de cette thèse, nous avons testé trois stratégies de neuroprotection sur des cultures de cellules en agrégats issues du cortex d'embryons de rats et traitées à l'ammoniaque. - Nous avons tout d'abord testé si l'inhibition de protéines intracellulaires impliquées dans le déclenchement de la mort cellulaire pouvait protéger les cellules de la toxicité de l'ammoniaque. Nous avons montré que L'exposition à l'ammoniaque altérait la viabilité des neurones et des oligodendrocytes, et activait les caspases, la calpaïne et la kinase-5 dépendante des cyclines (cdk5) associée à son activateur p25. Alors que l'inhibition pharmacologique des caspases et de la calpaïne n'a pas permis de protéger les cellules cérébrales, un inhibiteur de la cdk5, appelé roscovitine, a réduit significativement la mort neuronale. L'inhibition de la cdk5 semble donc être une stratégie thérapeutique prometteuse pour prévenir 1es effets toxiques de 1'ammoniaque sur les neurones. - Nous avons ensuite étudié les mécanismes neuroprotecteurs déclenchés par le cerveau en réponse à la toxicité de l'ammoniaque. Nous avons montré que l'ammoniaque induisait la synthèse du facteur neurotrophique ciliaire (CNTF) par les astrocytes, via l'activation de la protéine kinase (MIAPK) p38. D'autre part, l'ajout de CNTF a permis de protéger les oligodendrocytes mais pas les neurones des cultures exposées à l'ammoniaque, via les voies de signalisations JAK/STAT, SAPK/JNK et c-jun. - Dans une dernière partie, nous avons voulu contrecarrer, par l'ajout de créatine, le déficit énergétique cérébral induit par l'ammoniaque. La créatine a permis de protéger des cellules de type astrocytaire mais pas les cellules cérébrales en agrégats. Cette thèse amis en évidence que les stratégies de neuroprotection chez les patients hyperammonémiques nécessiteront de cibler plusieurs voies de signalisation afin de protéger tous les types cellulaires du cerveau. Summary : In pediatric patients, hyperammonemia is mainly caused by urea cycle disorders or other inborn errors of metabolism, and leads to neurological injury with cortical atrophy, ventricular enlargement and demyelination. Children rescued from neonatal hyperammonemia show significant risk of mental retardation and developmental disabilities. The mainstay of therapy is limited to ammonia lowering through dietary restriction and alternative pathway treatments. However, the possibility of using treatments in a neuroprotective goal may be useful to improve the neurological outcome of patients. Thus, the main objective of this work was to investigate intracellular and extracellular signaling pathways altered by ammonia tonicity, so as to identify new potential therapeutic targets. Experiments were conducted in reaggregated developing brain cell cultures exposed to ammonia, as a model for the developing CNS of hyperammonemic young patients. Theses strategies of neuroprotection were tested: - The first strategy consisted in inhibiting intracellular proteins triggering cell death. Our data indicated that ammonia exposure altered the viability of neurons and oligodendrocytes. Apoptosis and proteins involved in the trigger of apoptosis, such as caspases, calpain and cyclin-dependent kinase-5 (cdk5) with its activator p25, were activated by ammonia exposure. While caspases and calpain inhibitors exhibited no protective effects, roscovitine, a cdk5 inhibitor, reduced ammonia-induced neuronal death. This work revealed that inhibition of cdk5 seems a promising strategy to prevent the toxic effects of ammonia on neurons. - The second strategy consisted in mimicking, the endogenous protective mechanisms triggered by ammonia in the brain. Ammonia exposure caused an increase of the ciliary neurotrophic factor (CNTF) expression, through the activation of the p38 mitogen-activated protein kinase (MAPK) in astrocytes. Treatment of cultures exposed to ammonia with exogenous CNTF demonstrated strong protective effects on oligodendrocytes but not on neurons. These protective effects seemed to involve JAK/STAT, SAPK/JNK and c-jun proteins. - The third strategy consisted in preventing the ammonia-induced cerebral energy deficit with creatine. Creatine treatment protected the survival of astrocyte-like cells through MAPKs pathways. In contrast, it had no protective effects in reaggregated developing brain cell cultures exposed to ammonia. The present study suggests that neuroprotective strategies should optimally be directed at multiple targets to prevent ammonia-induced alterations of the different brain cell types.
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Because an individual's investment into the immune system may modify its dispersal rate, immune function may evolve rapidly in an invader. We collected cane toads (Rhinella marina) from sites spanning their 75-year invasion history in Australia, bred them, and raised their progeny in standard conditions. Evolved shifts in immune function should manifest as differences in immune responses among the progeny of parents collected in different locations. Parental location did not affect the offspring's cell-mediated immune response or stress response, but blood from the offspring of invasion-front toads had more neutrophils, and was more effective at phagocytosis and killing bacteria. These latter measures of immune function are negatively correlated with rate of dispersal in free-ranging toads. Our results suggest that the invasion of tropical Australia by cane toads has resulted in rapid genetically based compensatory shifts in the aspects of immune responses that are most compromised by the rigours of long-distance dispersal.
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The postsynaptic density protein PSD-95 is a major element of synapses. PSD-95 is involved in aging, Alzheimer's disease (AD) and numerous psychiatric disorders. However, contradictory data about PSD-95 expression in aging and AD have been reported. Indeed in AD versus control brains PSD-95 varies according to regions, increasing in the frontal cortex, at least in a primary stage, and decreasing in the temporal cortex. In contrast, in transgenic mouse models of aging and AD PSD-95 expression is decreased, in behaviorally aged impaired versus unimpaired rodents it can decrease or increase and finally, it is increased in rodents grown in enriched environments. Different factors explain these contradictory results in both animals and humans, among others concomitant psychiatric endophenotypes, such as depression. The possible involvement of PSD-95 in reactive and/or compensatory mechanisms during AD progression is underscored, at least before the occurrence of important synaptic elimination. Thus, in AD but not in AD transgenic mice, enhanced expression might precede the diminution commonly observed in advanced aging. A two-compartments cell model, separating events taking place in cell bodies and synapses, is presented. Overall these data suggest that AD research will progress by untangling pathological from protective events, a prerequisite for effective therapeutic strategies.
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Microtubule-associated protein 1B, MAP1B, is one of the major growth associated and cytoskeletal proteins in neuronal and glial cells. It is present as a full length protein or may be fragmented into a heavy chain and a light chain. It is essential to stabilize microtubules during the elongation of dendrites and neurites and is involved in the dynamics of morphological structures such as microtubules, microfilaments and growth cones. MAP1B function is modulated by phosphorylation and influences microtubule stability, microfilaments and growth cone motility. Considering its large size, several interactions with a variety of other proteins have been reported and there is increasing evidence that MAP1B plays a crucial role in the stability of the cytoskeleton and may have other cellular functions. Here we review molecular and functional aspects of this protein, evoke its role as a scaffold protein and have a look at several pathologies where the protein may be involved.
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The c-Jun N-terminal kinase (JNK) is a mitogen-activated protein kinase (MAPK) activated by stress-signals and involved in many different diseases. Previous results proved the powerful effect of the cell permeable peptide inhibitor d-JNKI1 (d-retro-inverso form of c-Jun N-terminal kinase-inhibitor) against neuronal death in CNS diseases, but the precise features of this neuroprotection remain unclear. We here performed cell-free and in vitro experiments for a deeper characterization of d-JNKI1 features in physiological conditions. This peptide works by preventing JNK interaction with its c-Jun N-terminal kinase-binding domain (JBD) dependent targets. We here focused on the two JNK upstream MAPKKs, mitogen-activated protein kinase kinase 4 (MKK4) and mitogen-activated protein kinase kinase 7 (MKK7), because they contain a JBD homology domain. We proved that d-JNKI1 prevents MKK4 and MKK7 activity in cell-free and in vitro experiments: these MAPKK could be considered not only activators but also substrates of JNK. This means that d-JNKI1 can interrupt downstream but also upstream events along the JNK cascade, highlighting a new remarkable feature of this peptide. We also showed the lack of any direct effect of the peptide on p38, MEK1, and extracellular signal-regulated kinase (ERK) in cell free, while in rat primary cortical neurons JNK inhibition activates the MEK1-ERK-Ets1/c-Fos cascade. JNK inhibition induces a compensatory effect and leads to ERK activation via MEK1, resulting in an activation of the survival pathway-(MEK1/ERK) as a consequence of the death pathway-(JNK) inhibition. This study should hold as an important step to clarify the strong neuroprotective effect of d-JNKI1.
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This report is presented in two parts . P a r t I takes a new look at the design of rest area stabilization ponds after nearly 10 years' experience with some of the existing ponds and in the light of new design standards issued by Iowa DEQ. The Iowa DOT is embarking on improvements t o the ponds a t some of the r e s t areas. These improvements may include installation of drainage tile around the ponds to lower the water table below the pond bottom, sealing of the ponds with bentonite clay to reduce the infiltration to limits recently established by Iowa DEQ, and the enlargement of the ponds installation of aeration equipment t o increase the pond capacity. As the Iowa DOT embarks on this improvement program, it behooves them t o make only the improvements that are absolutely necessary to achieve waste water treatment goals. These ponds are subject to an extremely seasonal load and thus the ordinary standards used for pond design are not appropriate. Thus, Part I of the report presents a rationale for design and operation of the ponds which is deemed appropriate for t h e i r unique seasonally loaded character. Part I1 of the report looks a t the feasibility of using wind power for the aeration of the ponds, if and when aeration is deemed necessary.
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In the pathogenesis of type 2 diabetes, hyperglycemia appears when ß cell mass and insulin secretory capacity are no longer sufficient to compensate for insulin resistance. The reduction in ß cell mass results from increased apoptosis. Therefore, finding strategies to preserve ß cell mass and function may be useful for the treatment or prevention of diabetes. Glucagon-like peptide-1 (GLP-1) protects ß cells against apoptosis, increases their glucose competence, and induces their proliferation. Previous studies in the lab of Prof. Bernard Thorens showed that the GLP-1 anti- apoptotic effect was mediated by robust up-regulation of IGF-1R expression, and this was paralleled with an increase in Akt phosphorylation. This effect was dependent not only on increased IGF-1R expression but also on the autocrine secretion of insulin-like growth factor 2 (IGF2). They also demonstrated that GLP-1 up-regulated IGF-1R expression by a protein a kinase A-dependent translational control mechanism. The main aim of this PhD work has been to further investigate the role of the IGF2/IGF-1 Receptor autocrine loop in ß cell function and to determine the physiological role of IGF2 in ß cell plasticity and its regulation by nutrients. This PhD thesis is divided in 3 chapters. The first chapter describes the role of IGF2/IGF-1R autocrine loop in ß cell glucose competence and proliferation. Here using MIN6 cells and primary mouse islets as an experimental model we demonstrated that the glucose competence of these cells was dependent on the level of IGF-1R expression and on IGF2 secretion. Furthermore, we showed that GLP-1-induced primary ß cell proliferation was significantly reduced by Igf-lr gene inactivation and by IGF2 immunoneutralization or knockdown. In the second chapter we examined the role of this IGF2/IGF-1R autocrine loop on the ß cell functional plasticity during ageing, pregnancy, and in response to acute induction of insulin resistance using mice with ß cell-specific inactivation of ig/2. Here we showed a gender-dependent role of ß cell IGF2 in ageing and high fat diet-induced metabolic stress; we demonstrated that the autocrine secretion of IGF2 is essential for ß cell mass adaptation during pregnancy. Further we also showed that this autocrine loop plays an important role in ß cell expansion in response to acute induction of insulin resistance. The aim of the third chapter was to investigate whether we can modulate the expression and secretion of IGF2 by nutrients in order to increase the activity of autocrine loop. Here we showed that glutamine induces IGF2 biosynthesis and its fast secretion through the regulated pathway, a mechanism enhanced in the presence of glucose. Furthermore, we demonstrated that glutamine-mediated Akt phosphorylation is dependent on IGF2 secretion, indicating that glutamine controls the activity of the IGF2/IGF1R autocrine loop through IGF2 up-regulation. In summary, this PhD work highlights that autocrine secretion of IGF2 is required for compensatory ß cell adaptation to ageing, pregnancy, and insulin resistance. Moreover IGF2/IGF1R autocrine loop is regulated by two feeding-related cues, GLP-1 to increase IGF-1R expression and glutamine to control IGF2 biosynthesis and secretion. -- Dans le diabète de type 2, lorsque la sécrétion d'insuline des cellules Beta du pancréas n'est plus suffisante pour compenser la résistance à l'insuline, une hyperglycémie est observée. Cette baisse de sécrétion d'insuline est Causée par la diminution de la masse de cellules Beta suite à l'augmentation du phénomène de mort cellulaire ou « apoptose ». En diabétologie, une des stratégies médicales concerne la préservation des cellules Beta du pancréas. Une des protéines intervenant dans cette fonction est GLP-1 (Glucagon-like peptide-1). GLP-1 est capable de protéger les cellules Beta contre la mort cellulaire et d'induire leur prolifération. Des études précédemment menées dans le laboratoire du Professeur Bernard Thorens ont montrées que l'activité « anti-apoptotique » de GLP-1 est le résultat l'une augmentation de l'expression du gène IGF-1R sous la dépendance de la sécrétion autocrine d'IGF2 (Insulin-Like Growth Factor). Le but de mon travail de thèse aura été d'étudier le mécanisme de la régulation de GLP-1 par IGF2 et plus précisément de déterminer le rôle physiologique d'IGF2 dans la plasticité des cellules ß ainsi que sa régulation par les nutriments. Ce manuscrit est ainsi divisé en trois chapitres : Le premier chapitre décrit la fonction d'IGF2/IGF- R1 dans la réponse des cellules Beta au glucose ainsi que dans leur capacité à proliférer. Dans ce chapitre nous avons montré l'importance du niveau d'expression d'IGFR-1 et de la sécrétion d'IGF2 dans la régulation du métabolisme du glucose. Dans un deuxième chapitre, nous étudions la boucle de régulation IGF2/IGF-R1 sur la plasticité des cellules Beta lors du vieillissement, de la grossesse ainsi que dans un modèle de souris résistantes à l'insuline. Cette étude met en évidence un dimorphisme sexuel dans le rôle d'IGF2 lors du vieillissement et lors d'un stress métabolique. Nous montrons également l'importance d'IGF2 pour l'adaptation des cellules Beta tout au long de la grossesse ou lors du phénomène de résistance à l'insuline. Dans un troisième chapitre, nous mettons en évidence la possibilité de moduler l'expression et la sécrétion d'IGF2 par les nutriments. En conclusion, ce travail de thèse aura permis de mettre en évidence l'importance d'IGF2 dans la plasticité des cellules ß, une plasticité indispensable lors du vieillissement, de la grossesse ou encore dans le cas d'une résistance à l'insuline.
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Glucocorticoids affect physiology and behaviour, reproduction and potentially sexual selection as well. Shortterm and moderate glucocorticoid elevations are suggested to be adaptive, and prolonged and high elevations may be extremely harmful. This suggests that optimal reproductive strategies, and thus sexual selection, may be dose dependent. Here, we investigate effects of moderate and high elevations of blood corticosterone levels on intra- and intersexual behaviour and mating success of male common lizards Lacerta vivipara. Females showed less interest and more aggressive behaviour towards high corticosterone males and blood corticosterone levels affected male reproductive strategy. Males of moderate and high corticosterone elevations, compared with Control males, showed increased interest (i.e., higher number of chases, tongue extrusions, and approaches) towards females and high corticosterone males initiated more copulation attempts. However, neither increased male interest nor increased copulation attempts resulted in more copulations. This provides evidence for a best-of-a-bad-job strategy, where males with higher corticosterone levels compensated for reduced female interest and increased aggressive female behaviour directed towards them, by showing higher interest and by conducting more copulation attempts. Blood corticosterone levels affected intrasexual selection as well since moderate corticosterone levels positively affected male dominance, but dominance did not affect mating success. These findings underline the importance of female mate choice and are in line with adaptive compensatory behaviours of males. They further show that glucocorticoid effects on behaviour are dose dependent and that they have important implications for sexual selection and social interactions, and might potentially affect Darwinian fitness.
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BACKGROUND: By reducing the amount of nicotine that reaches the brain when a person smokes a cigarette, nicotine vaccines may help people to stop smoking or to prevent recent quitters from relapsing. OBJECTIVES: The aims of this review are to assess the efficacy of nicotine vaccines for smoking cessation and for relapse prevention, and to assess the frequency and type of adverse events associated with the use of nicotine vaccines. SEARCH METHODS: We searched the Cochrane Tobacco Addiction Review Group specialised register for trials, using the term 'vaccine' in the title or abstract, or in a keyword (date of most recent search April 2012). To identify any other material including reviews and papers potentially relevant to the background or discussion sections, we also searched MEDLINE, EMBASE, and PsycINFO, combining terms for nicotine vaccines with terms for smoking and tobacco use, without design limits or limits for human subjects. We searched the Annual Meeting abstracts of the Society for Research on Nicotine and Tobacco up to 2012, using the search string 'vaccin'. We searched Google Scholar for 'nicotine vaccine'. We also searched company websites and Google for information related to specific vaccines. We searched clinicaltrials.gov in March 2012 for 'nicotine vaccine' and for the trade names of known vaccine candidates. SELECTION CRITERIA: We included randomized controlled trials of nicotine vaccines, at Phase II and Phase III trial stage and beyond, in adult smokers or recent ex-smokers. We included studies of nicotine vaccines used as part of smoking cessation or relapse prevention interventions. DATA COLLECTION AND ANALYSIS: We extracted data on the type of participants, the dose and duration of treatment, the outcome measures, the randomization procedure, concealment of allocation, blinding of participants and personnel, reporting of outcomes, and completeness of follow-up.Our primary outcome measure was a minimum of six months abstinence from smoking. We used the most rigorous definition of abstinence, and preferred cessation rates at 12 months and biochemically validated rates where available. We have used the risk ratio (RR) to summarize individual trial outcomes. We have not pooled the current group of included studies as they cover different vaccines and variable regimens. MAIN RESULTS: There are no nicotine vaccines currently licensed for public use, but there are a number in development. We found four trials which met our inclusion criteria, three comparing NicVAX to placebo and one comparing NIC002 (formerly NicQbeta) to placebo. All were smoking cessation trials conducted by pharmaceutical companies as part of the drug development process, and all trials were judged to be at high or unclear risk of bias in at least one domain. Overall, 2642 smokers participated in the included studies in this review. None of the four included studies detected a statistically significant difference in long-term cessation between participants receiving vaccine and those receiving placebo. The RR for 12 month cessation in active and placebo groups was 1.35 (95% Confidence Interval (CI) 0.82 to 2.22) in the trial of NIC002 and 1.74 (95% CI 0.73 to 4.18) in one NicVAX trial. Two Phase III NicVAX trials, for which full results were not available, reported similar quit rates of approximately 11% in both groups. In the two studies with full results available, post hoc analyses detected higher cessation rates in participants with higher levels of nicotine antibodies, but these findings are not readily generalisable. The two studies with full results showed nicotine vaccines to be well tolerated, with the majority of adverse events classified as mild or moderate. In the study of NIC002, participants receiving the vaccine were more likely to report mild to moderate adverse events, most commonly flu-like symptoms, whereas in the study of NicVAX there was no significant difference between the two arms. Information on adverse events was not available for the large Phase III trials of NicVAX.Vaccine candidates are likely to undergo significant changes before becoming available to the general public, and those included in this review may not be the first to reach market; this limits the external validity of the results reported in this review in terms of both effectiveness and tolerability. AUTHORS' CONCLUSIONS: There is currently no evidence that nicotine vaccines enhance long-term smoking cessation. Rates of serious adverse events recorded in the two trials with full data available were low, and the majority of adverse events reported were at mild to moderate levels. The evidence available suggests nicotine vaccines do not induce compensatory smoking or affect withdrawal symptoms. No nicotine vaccines are currently licensed for use in any country but a number are under development.Further trials of nicotine vaccines are needed, comparing vaccines with placebo for smoking cessation. Further trials are also needed to explore the potential of nicotine vaccines to prevent relapse. Results from past, current and future research should be reported in full. Adverse events and serious adverse events should continue to be carefully monitored and thoroughly reported.
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A 11 months old female infant from Portugal, free of family history, consults for apathy, weight loss, tachycardia, tachypnea, petechiae, pallor without icterus and hepatoslenomegaly. Seven months earlier, while being in Portugal, she presented a persistent bluish pimple on her buttock. Laboratory results showed anemia (35 g/l), leucopenia (3.3 G/l), thrombocytopenia (13 G/l), impaired coagulation (INR 1.4, PTT 41 sec.), hyponatremia (124 mmol/l), elevated CRP (139 mg/l), high ferritin (34.775 μg/l) and high triglycerides (5.22 mmol/l). After correction of vital parameters, a bone marrow aspiration and biopsy (BMB) revealed both the etiological diagnosis, namely a visceral leishmaniasis (VL) as well as one of its potential complications, the hemophagocytic syndrome (HS). Transfusions of whole blood, platelets and fresh frozen plasma were immediately started. Dexamethasone (10 mg/m2) and amphotericin B (3 mg/kg/day) have also been administrated. Visceral leishmaniasis is caused by a protozoan (Leishmania donovani) transmitted by the female sandfly. It is endemic in the Mediterranean basin (including France, Italy, Spain and Portugal), South America, sub-Saharan Africa as well as in India and Bangladesh. The parasite infects macrophages and, after several weeks of incubation, the disease occurs by affection of bloodlines (anemia, leucopenia, thrombocytopenia), hepatosplenomegaly, cachexia, gastrointestinal damage. The complications of the disease may lead to death. Liposomal amphotericin B is the currently recommended treatment. HS is caused by the proliferation and activation of macrophages in the marrow in response to a cytokine storm. It may be of primary cause. When it is secondary, it may be related to infections such as leishmaniasis. Patients present with fever and laboratory diagnostic criteria include cytopenia, hypertriglyceridemia, high ferritin and hemophagocytosis in the BMB. The treatment consists among other in the administration of high doses corticosteroids and, in secondary cases, in the treatment of the underlying cause. In conclusion, the clinical and biological features of VL may mimic haematological disorders as leukemia, but an enlargement of the liver and especially of the spleen should remind in this parasitic infection and its potential fatal complication, the HS.