340 resultados para Inhibitor discontinuation syndrome


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Lynch syndrome is one of the most common hereditary colorectal cancer (CRC) syndrome and is caused by germline mutations of MLH1, MSH2 and more rarely MSH6, PMS2, MLH3 genes. Whereas the absence of MSH2 protein is predictive of Lynch syndrome, it is not the case for the absence of MLH1 protein. The purpose of this study was to develop a sensitive and cost effective algorithm to select Lynch syndrome cases among patients with MLH1 immunohistochemical silencing. Eleven sporadic CRC and 16 Lynch syndrome cases with MLH1 protein abnormalities were selected. The BRAF c.1799T> A mutation (p.Val600Glu) was analyzed by direct sequencing after PCR amplification of exon 15. Methylation of MLH1 promoter was determined by Methylation-Sensitive Single-Strand Conformation Analysis. In patients with Lynch syndrome, there was no BRAF mutation and only one case showed MLH1 methylation (6%). In sporadic CRC, all cases were MLH1 methylated (100%) and 8 out of 11 cases carried the above BRAF mutation (73%) whereas only 3 cases were BRAF wild type (27%). We propose the following algorithm: (1) no further molecular analysis should be performed for CRC exhibiting MLH1 methylation and BRAF mutation, and these cases should be considered as sporadic CRC; (2) CRC with unmethylated MLH1 and negative for BRAF mutation should be considered as Lynch syndrome; and (3) only a small fraction of CRC with MLH1 promoter methylation but negative for BRAF mutation should be true Lynch syndrome patients. These potentially Lynch syndrome patients should be offered genetic counselling before searching for MLH1 gene mutations.

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Disease characteristics. Perry syndrome is characterized by parkinsonism, hypoventilation, depression, and weight loss. The mean age at onset is 48 years; the mean disease duration is five years. Parkinsonism and psychiatric changes (depression, apathy, character changes, and withdrawal) tend to occur early; severe weight loss and hypoventilation manifest later. Diagnosis/testing. The diagnosis is based on clinical findings and molecular genetic testing of DCTN1, the only gene known to be associated with Perry syndrome. Management. Treatment of manifestations: Dopaminergic therapy (particularly levodopa/carbidopa) should be considered in all individuals with significant parkinsonism. Although response to levodopa is often poor, some individuals may have long-term benefit. Noninvasive or invasive ventilation support may improve quality of life and prolong life expectancy. Those patients with psychiatric manifestations may benefit from antidepressants and psychiatric care. Weight loss is managed with appropriate dietary changes. Surveillance: routine evaluation of weight and calorie intake, respiratory function (particularly at night or during sleep), strength; and mood. Agents/circumstances to avoid: Central respiratory depressants (e.g., benzodiazepines, alcohol). Genetic counseling. Perry syndrome is inherited in an autosomal dominant manner. The proportion of cases attributed to de novo mutations is unknown. Each child of an individual with Perry syndrome has a 50% chance of inheriting the mutation. No laboratories offering molecular genetic testing for prenatal diagnosis are listed in the GeneTests Laboratory Directory; however, prenatal testing may be available through laboratories offering custom prenatal testing for families in which the disease-causing mutation has been identified.

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Excess reactive oxygen species (ROS) formation can trigger various pathological conditions such as inflammation, in which xanthine oxidase (XO) is one major enzymatic source of ROS. Although XO has been reported to play essential roles in inflammatory conditions, the molecular mechanisms underlying the involvement of XO in inflammatory pathways remain unclear. Febuxostat, a selective and potent inhibitor of XO, effectively inhibits not only the generation of uric acid but also the formation of ROS. In this study, therefore, we examined the effects of febuxostat on lipopolysaccharide (LPS)-mediated inflammatory responses. Here we show that febuxostat suppresses LPS-induced MCP-1 production and mRNA expression via activating MAPK phosphatase-1 (MKP-1) which, in turn, leads to dephosphorylation and inactivation of JNK in macrophages. Moreover, these effects of febuxostat are mediated by inhibiting XO-mediated intracellular ROS production. Taken together, our data suggest that XO mediates LPS-induced phosphorylation of JNK through ROS production and MKP-1 inactivation, leading to MCP-1 production in macrophages. These studies may bring new insights into the novel role of XO in regulating inflammatory process through MAPK phosphatase, and demonstrate the potential use of XO inhibitor in modulating the inflammatory processes.

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Hemorrhage and resuscitation (H/R) leads to phosphorylation of mitogen-activated stress kinases, an event that is associated with organ damage. Recently, a specific, cell-penetrating, protease-resistant inhibitory peptide of the mitogen-activated protein kinase c-JUN N-terminal kinase (JNK) was developed (D-JNKI-1). Here, using this peptide, we tested if inhibition of JNK protects against organ damage after H/R. Male Sprague-Dawley rats were treated with D-JNKI-1 (11 mg/kg, i.p.) or vehicle. Thirty minutes later, rats were hemorrhaged for 1 h to a MAP of 30 to 35 mmHg and then resuscitated with 60% of the shed blood and twice the shed blood volume as Ringer lactate. Tissues were harvested 2 h later. ANOVA with Tukey post hoc analysis or Kruskal-Wallis ANOVA on ranks, P < 0.05, was considered significant. c-JUN N-terminal kinase inhibition decreased serum alanine aminotransferase activity as a marker of liver injury by 70%, serum creatine kinase activity by 67%, and serum lactate dehydrogenase activity by 60% as compared with vehicle treatment. The histological tissue damage observed was blunted after D-JNKI-1 pretreatment both for necrotic and apoptotic cell death. Hepatic leukocyte infiltration and serum IL-6 levels were largely diminished after D-JNKI-1 pretreatment. The extent of oxidative stress as evaluated by immunohistochemical detection of 4-hydroxynonenal was largely abrogated after JNK inhibition. After JNK inhibition, activation of cJUN after H/R was also reduced. Hemorrhage and resuscitation induces a systemic inflammatory response and leads to end-organ damage. These changes are mediated, at least in part, by JNK. Therefore, JNK inhibition deserves further evaluation as a potential treatment option in patients after resuscitated blood loss.

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BACKGROUND: In myasthenia gravis, antibody-mediated blockade of acetylcholine receptors at the neuromuscular junction abolishes the naturally occurring 'safety factor' of synaptic transmission. Acetylcholinesterase inhibitors provide temporary symptomatic treatment of muscle weakness but there is controversy about their long-term efficacy, dosage and side effects. This is the second update of a review published in The Cochrane Library Issue 2, 2011. OBJECTIVES: To evaluate the efficacy of acetylcholinesterase inhibitors in all forms of myasthenia gravis. SEARCH METHODS: On 8 July 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE and EMBASE for randomised controlled trials and quasi-randomised controlled trials regarding usage of acetylcholinesterase inhibitors in myasthenia gravis. Two authors scanned the articles for any study eligible for inclusion. We also contacted the authors and known experts in the field to identify additional published or unpublished data and searched clinical trials registries for ongoing trials. SELECTION CRITERIA: The types of studies were randomised or quasi-randomised trials. Participants were myasthenia gravis patients diagnosed by an internationally accepted definition. The intervention was treatment with any form of acetylcholinesterase inhibitor. Types of outcome measures Primary outcome measureImprovement in the presenting symptoms within one to 14 days of the start of treatment. Secondary outcome measures(1) Improvement in the presenting symptoms more than 14 days after the start of treatment.(2) Change in impairment measured by a recognised and preferably validated scale, such as the quantitative myasthenia gravis score, within one to 14 days and more than 14 days after the start of treatment.(3) Myasthenia Gravis Association of America post-intervention status more than 14 days after start of treatment.(4) Adverse events including muscarinic side effects. DATA COLLECTION AND ANALYSIS: One author (MMM) extracted the data, which were checked by a second author. We contacted study authors for extra information and collected data on adverse effects from the trials. MAIN RESULTS: We did not find any large randomised or quasi-randomised trials of acetylcholinesterase inhibitors in generalised myasthenia gravis either for the first version of this review or this update. One cross-over randomised trial using intranasal neostigmine in a total of 10 participants was only available as an abstract. It included three participants with ocular myasthenia gravis and seven with generalised myasthenia gravis. Symptoms of myasthenia gravis (measured as improvement in at least one muscle function) improved in nine of the 10 participants after the two-week neostigmine treatment phase. No participant improved after the placebo phase. Lack of detail in the report meant that the risk of bias was unclear. Adverse events were minor. AUTHORS' CONCLUSIONS: Except for one small and inconclusive trial of intranasal neostigmine, no other randomised controlled trials have been conducted on the use of acetylcholinesterase inhibitors in myasthenia gravis. The response to acetylcholinesterase inhibitors in observational studies is so clear that a randomised controlled trial depriving participants in a placebo arm of treatment would be difficult to justify.

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Cellular inhibitor of apoptosis (cIAP) proteins, cIAP1 and cIAP2, are important regulators of tumor necrosis factor (TNF) superfamily (SF) signaling and are amplified in a number of tumor types. They are targeted by IAP antagonist compounds that are undergoing clinical trials. IAP antagonist compounds trigger cIAP autoubiquitylation and degradation. The TNFSF member TWEAK induces lysosomal degradation of TRAF2 and cIAPs, leading to elevated NIK levels and activation of non-canonical NF-kappaB. To investigate the role of the ubiquitin ligase RING domain of cIAP1 in these pathways, we used cIAP-deleted cells reconstituted with cIAP1 point mutants designed to interfere with the ability of the RING to dimerize or to interact with E2 enzymes. We show that RING dimerization and E2 binding are required for IAP antagonists to induce cIAP1 degradation and protect cells from TNF-induced cell death. The RING functions of cIAP1 are required for full TNF-induced activation of NF-kappaB, however, delayed activation of NF-kappaB still occurs in cIAP1 and -2 double knock-out cells. The RING functions of cIAP1 are also required to prevent constitutive activation of non-canonical NF-kappaB by targeting NIK for proteasomal degradation. However, in cIAP double knock-out cells TWEAK was still able to increase NIK levels demonstrating that NIK can be regulated by cIAP-independent pathways. Finally we show that, unlike IAP antagonists, TWEAK was able to induce degradation of cIAP1 RING mutants. These results emphasize the critical importance of the RING of cIAP1 in many signaling scenarios, but also demonstrate that in some pathways RING functions are not required.

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A 28-month-old boy was referred for acute onset of abnormal head movements. History revealed an insidious progressive regression in behaviour and communication over several months. Head and shoulder 'spasms' with alteration of consciousness and on one occasion ictal laughter were seen. The electroencephalograph (EEG) showed repeated bursts of brief generalized polyspikes and spike-wave during the 'spasms', followed by flattening, a special pattern which never recurred after treatment. Review of family videos showed a single 'minor' identical seizure 6 months previously. Magnetic resonance imaging was normal. Clonazepam brought immediate cessation of seizures, normalization of the EEG and a parallel spectacular improvement in communication, mood and language. Follow-up over the next 10 months showed a new regression unaccompained by recognized seizures, although numerous seizures were discovered during the videotaped neuropsychological examination, when stereotyped subtle brief paroxysmal changes in posture and behaviour could be studied in slow motion and compared with the 'prototypical' initial ones. The EEG showed predominant rare left-sided fronto-temporal discharges. Clonazepam was changed to carbamazepin with marked improvement in behaviour, language and cognition which has been sustained up to the last control at 51 months. Videotaped home observations allowed the documentation of striking qualitative and quantitative variations in social interaction and play of autistic type in relation to the epileptic activity. We conclude that this child has a special characteristic epileptic syndrome with subtle motor and vegetative symptomatology associated with an insidious catastrophic 'autistic-like' regression which could be overlooked. The methods used to document such fluctuating epileptic behavioural manifestations are discussed.

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Introduction: Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability. With no curative treatment available, current therapeutic approaches are aimed at symptom management. FXS is caused by silencing the FMR1 gene, which encodes FMRP; as loss of FMRP leads to the development of symptoms associated with FXS. Areas covered: In this evaluation, the authors examine the role of the metabotropic glutamate receptor 5 (mGluR5) in the pathophysiology of FXS, and its suitability as a target for rescuing the disease state. Furthermore, the authors review the evidence from preclinical studies of pharmacological interventions targeting mGluR5 in FXS. Lastly, the authors assess the findings from clinical studies in FXS, in particular the use of the Aberrant Behavior Checklist-Community Edition (ABC-C) and the recently developed ABC-C for FXS scale, as clinical endpoints to assess disease modification in this patient population. Expert opinion: There is cautious optimism for the successful treatment of the core behavioral and cognitive symptoms of FXS based on preclinical data in animal models and early studies in humans. However, the association between mGluR5-heightened responsiveness and the clinical phenotype in humans remains to be demonstrated. Many questions regarding the optimal treatment and outcome measures of FXS remain unanswered.

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Brittle cornea syndrome (BCS) is an autosomal recessive disorder characterised by extreme corneal thinning and fragility. Corneal rupture can therefore occur either spontaneously or following minimal trauma in affected patients. Two genes, ZNF469 and PRDM5, have now been identified, in which causative pathogenic mutations collectively account for the condition in nearly all patients with BCS ascertained to date. Therefore, effective molecular diagnosis is now available for affected patients, and those at risk of being heterozygous carriers for BCS. We have previously identified mutations in ZNF469 in 14 families (in addition to 6 reported by others in the literature), and in PRDM5 in 8 families (with 1 further family now published by others). Clinical features include extreme corneal thinning with rupture, high myopia, blue sclerae, deafness of mixed aetiology with hypercompliant tympanic membranes, and variable skeletal manifestations. Corneal rupture may be the presenting feature of BCS, and it is possible that this may be incorrectly attributed to non-accidental injury. Mainstays of management include the prevention of ocular rupture by provision of protective polycarbonate spectacles, careful monitoring of visual and auditory function, and assessment for skeletal complications such as developmental dysplasia of the hip. Effective management depends upon appropriate identification of affected individuals, which may be challenging given the phenotypic overlap of BCS with other connective tissue disorders.

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ABSTRACT Objectives: Patients with failed back surgery syndrome (FBSS) and chronic neuropathic pain experience levels of health-related quality of life (HRQoL) that are considerably lower than those reported in other areas of chronic pain. The aim of this article was to quantify the extent to which reductions in (leg and back) pain and disability over time translate into improvements in generic HRQoL as measured by the EuroQoL-5D and SF-36 instruments. Methods: Using data from the multinational Prospective, Randomized, Controlled, Multicenter Study of Patients with Failed Back Surgery Syndrome trial, we explore the relationship between generic HRQoL-assessed using two instruments often used in clinical trials (i.e., the SF-36 and EuroQol-5D)-and disease-specific outcome measures (i.e., Oswestry disability index [ODI], leg and back pain visual analog scale [VAS]) in neuropathic patients with FBSS. Results: In our sample of 100 FBSS patients, generic HRQoL was moderately associated with ODI (correlation coefficient: -0.462 to -0.638) and mildly associated with leg pain VAS (correlation coefficient: -0.165 to -0.436). The multilevel regression analysis results indicate that functional ability (as measured by the ODI) is significantly associated with HRQoL, regardless of the generic HRQoL instrument used. On the other hand, changes over time in leg pain were significantly associated with changes in the EuroQoL-5D and physical component summary scores, but not with the mental component summary score. Conclusions: Reduction in leg pain and functional disability is statistically significantly associated with improvements in generic HRQoL. This is the first study to investigate the longitudinal relationship between generic and disease-specific HRQoL of neuropathic pain patients with FBSS, using multinational data.

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A few recent individual case reports have suggested that a myasthenic syndrome may be associated with statin treatment, but this association is not well described. We report 4 patients who developed symptoms of myasthenia gravis within 2 weeks of starting treatment with a statin drug. In 1 case the drug appears to have exacerbated underlying myasthenic weakness, whereas in the other 3 cases, de novo antibody formation appears to be most likely. In each case, some degree of recovery followed discontinuation of the statin medication.

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PURPOSE: Platelet-derived growth factor receptor-alpha (PDGFRA) mutations are found in approximately 5% to 7% of advanced gastrointestinal stromal tumors (GIST). We sought to extensively assess the activity of imatinib in this subgroup. EXPERIMENTAL DESIGN: We conducted an international survey among GIST referral centers to collect clinical data on patients with advanced PDGFRA-mutant GISTs treated with imatinib for advanced disease. RESULTS: Fifty-eight patients were included, 34 were male (59%), and median age at treatment initiation was 61 (range, 19-83) years. The primary tumor was gastric in 40 cases (69%). Thirty-two patients (55%) had PDGFRA-D842V substitutions whereas 17 (29%) had mutations affecting other codons of exon 18, and nine patients (16%) had mutation in other exons. Fifty-seven patients were evaluable for response, two (4%) had a complete response, eight (14%) had a partial response, and 23 (40%) had stable disease. None of 31 evaluable patients with D842V substitution had a response, whereas 21 of 31 (68%) had progression as their best response. Median progression-free survival was 2.8 [95% confidence interval (CI), 2.6-3.2] months for patients with D842V substitution and 28.5 months (95% CI, 5.4-51.6) for patients with other PDGFRA mutations. With 46 months of follow-up, median overall survival was 14.7 months for patients with D842V substitutions and was not reached for patients with non-D842V mutations. CONCLUSIONS: This study is the largest reported to date on patients with advanced PDGFRA-mutant GISTs treated with imatinib. Our data confirm that imatinib has little efficacy in the subgroup of patients with D842V substitution in exon 18, whereas other mutations appear to be sensitive to imatinib. Clin Cancer Res; 18(16); 4458-64. ©2012 AACR.

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Background: The metabolic syndrome (MS) represents a cluster of metabolic disorders that predicts diabetes and cardiovascular disease. Several definitions exist and further descriptive and prospective data are needed to compare these definitions and their significance in different populations. Objective: We examined, in a country of the African region, i) the prevalence of MS according to three major definitions (ATP, IDF, WHO); ii) the contribution of individual MS components; and iii) the agreement between the three considered definitions. We also examined the prevalence among diabetics and non-diabetics. Methods: We conducted an examination survey in a sample representative of the general population aged 25-64 of the Seychelles (Indian Ocean, African region), attended by 1255 persons (participation rate of 80.2%). Results: The prevalence of MS was similar with either definition of MS in men (24%--25%) but differed in women (WHO: 25%, ATP: 32%; IDF: 35%). Upon exclusion of diabetic persons, the prevalence was 5-10% lower for all three MS definitions: most diabetic persons had MS although a substantial proportion of diabetic men aged 45--64 did not have MS. The following components were found most often among persons with MS: 90% had high blood pressure (HBP) and 78% had obesity (ATP); 95% had obesity and 84% had HBP (WHO), and 89% had HBP and 75% had impaired glucose regulation (IDF) - not considering impaired glucose regulation and obesity that are compulsory components of the WHO and IDF definitions, respectively. Among persons with MS based on either of the three definitions (37% of total population), less than 80% met both ATP and IDF criteria, 67% both WHO and IDF criteria, 54% both WHO and ATP criteria and only 37% met all three definitions. Conclusion: We found a fairly high prevalence of MS in an African population. However, because there was only poor agreement between the 3 MS definitions, the fairly similar proportions of MS based on ATP, IDF or WHO definitions identified, to a substantial extent, different subjects as having MS.