RESUMO
Unique strains of α-synuclein aggregates have been postulated to underlie the spectrum of clinical and pathological presentations seen across the synucleinopathies. Whereas multiple system atrophy (MSA) is associated with a predominance of oligodendroglial α-synuclein inclusions, α-synuclein aggregates in Parkinson's disease (PD) preferentially accumulate in neurons. The G51D mutation in the SNCA gene encoding α-synuclein causes an aggressive, early-onset form of PD that exhibits clinical and neuropathological traits reminiscent of both PD and MSA. To assess the strain characteristics of G51D PD α-synuclein aggregates, we performed propagation studies in M83 transgenic mice by intracerebrally inoculating patient brain extracts. The properties of the induced α-synuclein aggregates in the brains of injected mice were examined using immunohistochemistry, a conformational stability assay, and by performing α-synuclein seed amplification assays. Unlike MSA-injected mice, which developed a progressive motor phenotype, G51D PD-inoculated animals remained free of overt neurological illness for up to 18 months post-inoculation. However, a subclinical synucleinopathy was present in G51D PD-inoculated mice, characterized by the accumulation of α-synuclein aggregates in restricted regions of the brain. The induced α-synuclein aggregates in G51D PD-injected mice exhibited distinct properties in a seed amplification assay and were much more stable than those present in mice injected with MSA extract, which mirrored the differences observed between human MSA and G51D PD brain samples. These results suggest that the G51D SNCA mutation specifies the formation of a slowly propagating α-synuclein strain that more closely resembles α-synuclein aggregates associated with PD than MSA.
Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Sinucleinopatias , Humanos , Camundongos , Animais , alfa-Sinucleína/genética , alfa-Sinucleína/química , Doença de Parkinson/genética , Doença de Parkinson/patologia , Atrofia de Múltiplos Sistemas/genética , Atrofia de Múltiplos Sistemas/patologia , Mutação/genética , Sinucleinopatias/genética , Camundongos TransgênicosRESUMO
Urethane, an acute laboratory anesthetic, produces distinct neurophysiological and physiological effects creating an effective model of the dynamics of natural sleep. As a model of both sleep-like neurophysiological activity and the downstream peripheral function urethane is used to model a variety of physiological and pathophysiological processes. As urethane is typically administered as a single-bolus dose, it is unclear the stability of peripheral physiological functions both within and between brain-states under urethane anesthesia. In this present study, we recorded respiration rate and heart rate concurrently with local field potentials from the neocortex and hippocampus to determine the stability of peripheral physiological functions within and between brain-states under urethane anesthesia. Our data shows electroencephalographic characteristics and breathing rate are remarkable stable over long-term recordings within minor reductions in heart rate on the same time scale. Our findings indicate that the use of urethane to model peripheral physiological functions associated with changing brain states are stable during long duration experiments.
Assuntos
Anestésicos Intravenosos/farmacologia , Encéfalo/efeitos dos fármacos , Ritmo Teta/efeitos dos fármacos , Uretana/farmacologia , Animais , Encéfalo/fisiologia , Eletroencefalografia , Masculino , Ratos , Ratos Sprague-Dawley , Taxa Respiratória/efeitos dos fármacos , Sono/efeitos dos fármacos , Sono/fisiologia , Ritmo Teta/fisiologiaRESUMO
OBJECTIVE: This study was undertaken to identify susceptibility loci for cluster headache and obtain insights into relevant disease pathways. METHODS: We carried out a genome-wide association study, where 852 UK and 591 Swedish cluster headache cases were compared with 5,614 and 1,134 controls, respectively. Following quality control and imputation, single variant association testing was conducted using a logistic mixed model for each cohort. The 2 cohorts were subsequently combined in a merged analysis. Downstream analyses, such as gene-set enrichment, functional variant annotation, prediction and pathway analyses, were performed. RESULTS: Initial independent analysis identified 2 replicable cluster headache susceptibility loci on chromosome 2. A merged analysis identified an additional locus on chromosome 1 and confirmed a locus significant in the UK analysis on chromosome 6, which overlaps with a previously known migraine locus. The lead single nucleotide polymorphisms were rs113658130 (p = 1.92 × 10-17 , odds ratio [OR] = 1.51, 95% confidence interval [CI] = 1.37-1.66) and rs4519530 (p = 6.98 × 10-17 , OR = 1.47, 95% CI = 1.34-1.61) on chromosome 2, rs12121134 on chromosome 1 (p = 1.66 × 10-8 , OR = 1.36, 95% CI = 1.22-1.52), and rs11153082 (p = 1.85 × 10-8 , OR = 1.30, 95% CI = 1.19-1.42) on chromosome 6. Downstream analyses implicated immunological processes in the pathogenesis of cluster headache. INTERPRETATION: We identified and replicated several genome-wide significant associations supporting a genetic predisposition in cluster headache in a genome-wide association study involving 1,443 cases. Replication in larger independent cohorts combined with comprehensive phenotyping, in relation to, for example, treatment response and cluster headache subtypes, could provide unprecedented insights into genotype-phenotype correlations and the pathophysiological pathways underlying cluster headache. ANN NEUROL 2021;90:193-202.
Assuntos
Cefaleia Histamínica/epidemiologia , Cefaleia Histamínica/genética , Loci Gênicos/genética , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Estudos de Casos e Controles , Cefaleia Histamínica/diagnóstico , Estudos de Coortes , Feminino , Humanos , Masculino , Suécia/epidemiologia , Reino Unido/epidemiologiaRESUMO
INTRODUCTION: Non-invasive vagus nerve stimulation (nVNS; gammaCore®) has the potential to prevent migraine days in patients with migraine on the basis of mechanistic rationale and pilot clinical data. METHODS: This multicentre study included a 4-week run-in period, a 12-week double-blind period of randomised treatment with nVNS or sham, and a 24-week open-label period of nVNS. Patients were to administer two 120-second stimulations bilaterally to the neck three times daily (6-8 hours apart). RESULTS: Of 477 enrolled patients, 332 comprised the intent-to-treat (ITT) population. Mean reductions in migraine days per month (primary outcome) were 2.26 for nVNS (n = 165; baseline, 7.9 days) and 1.80 for sham (n = 167; baseline, 8.1 days) (p = 0.15). Results were similar across other outcomes. Upon observation of suboptimal adherence rates, post hoc analysis of patients with ≥ 67% adherence per month demonstrated significant differences between nVNS (n = 138) and sham (n = 140) for outcomes including reduction in migraine days (2.27 vs. 1.53; p = 0.043); therapeutic gains were greater in patients with aura than in those without aura. Most nVNS device-related adverse events were mild and transient, with application site discomfort being the most common. CONCLUSIONS: Preventive nVNS treatment in episodic migraine was not superior to sham stimulation in the ITT population. The "sham" device inadvertently provided a level of active vagus nerve stimulation. Post hoc analysis showed significant effects of nVNS in treatment-adherent patients. Study identification and registration: PREMIUM; NCT02378844; https://clinicaltrials.gov/ct2/show/NCT02378844.
Assuntos
Transtornos de Enxaqueca/prevenção & controle , Estimulação do Nervo Vago/métodos , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Herpes simplex virus (HSV) encephalitis affects 2-4 people per million/year. Immunocompomised patients can have atypical presentations of HSV encephalitis, including a lack of cerebrospinal fluid (CSF) pleocytosis. We present the case of a patient who was receiving ustekinumab therapy for psoriasis which inhibits interleukin (IL)-12 and IL-23 signalling pathways. The initial presentation was suggestive of encephalitis, but he was discharged prior to the reporting of HSV positivity due to the lack of CSF pleocytosis. On representation, he had worsening symptoms and imaging showed midline shift, indicating cerebral oedema despite the immunosupressant effects of ustekinumab. He required intensive care unit support and treatment with high dose aciclovir and dexamethasone; after a month of treatment he made a good recovery. This case is the first to report a link between ustekinumab and HSV encephalitis, and also emphasises that imunocompromised patients can lack CSF pleocytosis and develop significant cerebral oedema which responds to immune suppression.
Assuntos
Anti-Inflamatórios/uso terapêutico , Edema Encefálico/diagnóstico , Fármacos Dermatológicos/efeitos adversos , Encefalite por Herpes Simples/diagnóstico , Hospedeiro Imunocomprometido , Ustekinumab/efeitos adversos , Aciclovir/administração & dosagem , Aciclovir/uso terapêutico , Adulto , Anti-Inflamatórios/administração & dosagem , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Edema Encefálico/induzido quimicamente , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/tratamento farmacológico , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Diagnóstico Diferencial , Encefalite por Herpes Simples/líquido cefalorraquidiano , Encefalite por Herpes Simples/induzido quimicamente , Encefalite por Herpes Simples/tratamento farmacológico , Humanos , Masculino , Psoríase/tratamento farmacológicoRESUMO
BACKGROUND: The widespread global access to antiretroviral drugs has led to considerable reductions in morbidity and mortality but, unfortunately, the risk of virologic failure increases with the emergence, and potential transmission, of drug resistant viruses. Detecting and quantifying HIV-1 drug resistance has therefore become the standard of care when designing new antiretroviral regimens. The sensitivity of Sanger sequencing-based HIV-1 genotypic assays is limited by its inability to identify minority members of the quasispecies, i.e., it only detects variants present above ~ 20% of the viral population, thus, failing to detect minority variants below this threshold. It is clear that deep sequencing-based HIV-1 genotyping assays are an important step change towards accurately monitoring HIV-infected individuals. METHODS: We implemented and verified a clinically validated HIV-1 genotyping assay based on deep sequencing (DEEPGEN™) in two clinical laboratories in the United Kingdom: St. George's University Hospitals Healthcare NHS Foundation Trust (London) and at NHS Lothian (Edinburgh), to characterize minority HIV-1 variants in 109 plasma samples from ART-naïve or -experienced individuals. RESULTS: Although subtype B HIV-1 strains were highly prevalent (44%, 48/109), most individuals were infected with non-B subtype viruses (i.e., A1, A2, C, D, F1, G, CRF02_AG, and CRF01_AE). DEEPGEN™ was able to accurately detect drug resistance-associated mutations not identified using standard Sanger sequencing-based tests, which correlated significantly with patient's antiretroviral treatment histories. A higher proportion of minority PI-, NRTI-, and NNRTI-resistance mutations was detected in NHS Lothian patients compared to individuals from St. George's, mainly M46I/L and I50 V (associated with PIs), D67 N, K65R, L74I, M184 V/I, and K219Q (NRTIs), and L100I (NNRTIs). Interestingly, we observed an inverse correlation between intra-patient HIV-1 diversity and CD4+ T cell counts in the NHS Lothian patients. CONCLUSIONS: This is the first study evaluating the transition, training, and implementation of DEEPGEN™ between three clinical laboratories in two different countries. More importantly, we were able to characterize the HIV-1 drug resistance profile (including minority variants), coreceptor tropism, subtyping, and intra-patient viral diversity in patients from the United Kingdom, providing a rigorous foundation for basing clinical decisions on highly sensitive and cost-effective deep sequencing-based HIV-1 genotyping assays in the country.
Assuntos
Farmacorresistência Viral , Variação Genética , Genótipo , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/genética , Tropismo Viral , Adulto , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Feminino , Genes Virais , Infecções por HIV/tratamento farmacológico , HIV-1/classificação , HIV-1/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Filogenia , Reino Unido/epidemiologia , Carga ViralRESUMO
Fetal hemoglobin (HbF) is a strong modifier of sickle cell disease (SCD) severity and is associated with 3 common genetic loci. Quantifying the genetic effects of the 3 loci would specifically address the benefits of HbF increases in patients. Here, we have applied statistical methods using the most representative variants: rs1427407 and rs6545816 in BCL11A, rs66650371 (3-bp deletion) and rs9376090 in HMIP-2A, rs9494142 and rs9494145 in HMIP-2B, and rs7482144 (Xmn1-HBG2 in the ß-globin locus) to create g(HbF), a genetic quantitative variable for HbF in SCD. Only patients aged ≥5 years with complete genotype and HbF data were studied. Five hundred eighty-one patients with hemoglobin SS (HbSS) or HbSß0 thalassemia formed the "discovery" cohort. Multiple linear regression modeling rationalized the 7 variants down to 4 markers (rs6545816, rs1427407, rs66650371, and rs7482144) each independently contributing HbF-boosting alleles, together accounting for 21.8% of HbF variability (r2) in the HbSS or HbSß0 patients. The model was replicated with consistent r2 in 2 different cohorts: 27.5% in HbSC patients (N = 186) and 23% in 994 Tanzanian HbSS patients. g(HbF), our 4-variant model, provides a robust approach to account for the genetic component of HbF in SCD and is of potential utility in sickle genetic and clinical studies.
Assuntos
Anemia Falciforme/genética , Hemoglobina Fetal/genética , Modelos Genéticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Pré-Escolar , Inglaterra , Loci Gênicos , Variação Genética , Genótipo , Hemoglobina Falciforme/genética , Humanos , Pessoa de Meia-Idade , Adulto JovemRESUMO
Background Clinical observations and results from recent studies support the use of non-invasive vagus nerve stimulation (nVNS) for treating cluster headache (CH) attacks. This study compared nVNS with a sham device for acute treatment in patients with episodic or chronic CH (eCH, cCH). Methods After completing a 1-week run-in period, subjects were randomly assigned (1:1) to receive nVNS or sham therapy during a 2-week double-blind period. The primary efficacy endpoint was the proportion of all treated attacks that achieved pain-free status within 15 minutes after treatment initiation, without rescue treatment. Results The Full Analysis Set comprised 48 nVNS-treated (14 eCH, 34 cCH) and 44 sham-treated (13 eCH, 31 cCH) subjects. For the primary endpoint, nVNS (14%) and sham (12%) treatments were not significantly different for the total cohort. In the eCH subgroup, nVNS (48%) was superior to sham (6%; p < 0.01). No significant differences between nVNS (5%) and sham (13%) were seen in the cCH subgroup. Conclusions Combing both eCH and cCH patients, nVNS was no different to sham. For the treatment of CH attacks, nVNS was superior to sham therapy in eCH but not in cCH. These results confirm and extend previous findings regarding the efficacy, safety, and tolerability of nVNS for the acute treatment of eCH.
Assuntos
Cefaleia Histamínica/diagnóstico , Cefaleia Histamínica/terapia , Estimulação do Nervo Vago/métodos , Doença Aguda , Adulto , Doença Crônica , Cefaleia Histamínica/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Estudos Prospectivos , Resultado do Tratamento , Estimulação do Nervo Vago/tendênciasRESUMO
BACKGROUND: Cluster headache (CH) is a debilitating condition that is generally associated with substantial health care costs. Few therapies are approved for abortive or prophylactic treatment. Results from the prospective, randomised, open-label PREVA study suggested that adjunctive treatment with a novel non-invasive vagus nerve stimulation (nVNS) device led to decreased attack frequency and abortive medication use in patients with chronic CH (cCH). Herein, we evaluate whether nVNS is cost-effective compared with the current standard of care (SoC) for cCH. METHODS: A pharmacoeconomic model from the German statutory health insurance perspective was developed to estimate the 1-year cost-effectiveness of nVNS + SoC (versus SoC alone) using data from PREVA. Short-term treatment response data were taken from the clinical trial; longer-term response was modelled under scenarios of response maintenance, constant rate of response loss, and diminishing rate of response loss. Health-related quality of life was estimated by modelling EQ-5D™ data from PREVA; benefits were defined as quality-adjusted life-years (QALY). Abortive medication use data from PREVA, along with costs for the nVNS device and abortive therapies (i.e. intranasal zolmitriptan, subcutaneous sumatriptan, and inhaled oxygen), were used to assess health care costs in the German setting. RESULTS: The analysis resulted in mean expected yearly costs of 7096.69 for nVNS + SoC and 7511.35 for SoC alone and mean QALY of 0.607 for nVNS + SoC and 0.522 for SoC alone, suggesting that nVNS generates greater health benefits for lower overall cost. Abortive medication costs were 23 % lower with nVNS + SoC than with SoC alone. In the alternative scenarios (i.e. constant rate of response loss and diminishing rate of response loss), nVNS + SoC was more effective and cost saving than SoC alone. CONCLUSIONS: In all scenarios modelled from a German perspective, nVNS was cost-effective compared with current SoC, which suggests that adjunctive nVNS therapy provides economic benefits in the treatment of cCH. Notably, the current analysis included only costs associated with abortive treatments. Treatment with nVNS will likely promote further economic benefit when other potential sources of cost savings (e.g. reduced frequency of clinic visits) are considered. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT01701245 , 03OCT2012.
Assuntos
Cefaleia Histamínica/terapia , Custos de Cuidados de Saúde , Estimulação do Nervo Vago/economia , Cefaleia Histamínica/economia , Análise Custo-Benefício , Humanos , Modelos Econômicos , Estudos Prospectivos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Resultado do TratamentoRESUMO
INTRODUCTION: Subarachnoid haemorrhage (SAH) may arise spontaneously or as a result of trauma. Spontaneous SAH accounts for about 5% of all strokes. Ruptured aneurysms are the cause of 85% of spontaneous SAH. The most characteristic clinical feature is sudden-onset severe headache. Other features include vomiting, photophobia, and focal neurological deficit or seizures, or both. As the headache may have insidious onset in some cases, or may even be absent, a high degree of suspicion is required to diagnose SAH with less typical presentations. METHODS AND OUTCOMES: We conducted a systematic review, aiming to answer the following clinical question: What are the effects of surgical treatments for people with confirmed aSAH? We searched: Medline, Embase, The Cochrane Library, and other important databases up to October 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). RESULTS: At this update, searching of electronic databases retrieved 82 studies. After deduplication and removal of conference abstracts, 47 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 33 studies and the further review of 14 full publications. Of the 14 full articles evaluated, one systematic review, one RCT, and four further reports were added at this update. We performed a GRADE evaluation for six PICO combinations. CONCLUSIONS: In this systematic overview, we categorised the efficacy for one comparison based on information about the effectiveness and safety of endovascular coiling versus surgical clipping.
Assuntos
Procedimentos Endovasculares/normas , Hemorragia Subaracnóidea/cirurgia , Humanos , Instrumentos CirúrgicosRESUMO
INTRODUCTION: Chronic tension-type headache (CTTH) is a disorder that evolves from episodic tension-type headache, with daily, or very frequent, episodes of headache lasting hours or they may be continuous. It affects up to 4% of the general population, and is more prevalent in women (up to 65% of cases). METHODS AND OUTCOMES: We conducted a systematic overview, aiming to answer the following clinical questions: What are the effects of drug treatments for CTTH? What are the effects of non-drug treatments for CTTH? We searched: Medline, Embase, The Cochrane Library, and other important databases up to December 2013 (Clinical Evidence overviews are updated periodically; please check our website for the most up-to-date version of this overview). RESULTS: At this update, searching of electronic databases retrieved 125 studies. After deduplication, 77 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 56 studies and the further review of 21 full publications. Of the 21 full articles evaluated, three systematic reviews and one RCT were included at this update. We performed a GRADE evaluation for 15 PICO combinations. CONCLUSIONS: In this systematic overview, we categorised the efficacy for 12 interventions based on information about the effectiveness and safety of non-drug treatments acupuncture and cognitive behavioural therapy (CBT), as well as the drug treatments amitriptyline, anticonvulsant drugs (sodium valproate, topiramate, or gabapentin), benzodiazepines, botulinum toxin, noradrenergic and specific serotonergic antidepressants (mirtazapine), NSAIDs (e.g. ibuprofen); opioid analgesics (e.g. codeine), paracetamol, serotonin re-uptake inhibitor antidepressants (SSRIs, SNRIs), and tricyclic antidepressants (other than amitriptyline).
Assuntos
Cefaleia do Tipo Tensional/terapia , Analgésicos Opioides/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Antidepressivos/uso terapêutico , Doença Crônica , Terapia Cognitivo-Comportamental , Humanos , Inibidores Seletivos de Recaptação de Serotonina/uso terapêuticoRESUMO
BACKGROUND: Chronic cluster headache (CH) is a debilitating disorder for which few well-controlled studies demon.strate effectiveness of available therapies. Non-invasive vagus nerve stimulation (nVNS) was examined as adjunctive prophylactic treatment of chronic CH. METHODS: PREVA was a prospective, open-label, randomised study that compared adjunctive prophylactic nVNS (n = 48) with standard of care (SoC) alone (control (n = 49)). A two-week baseline phase was followed by a four-week randomised phase (SoC plus nVNS vs control) and a four-week extension phase (SoC plus nVNS). The primary end point was the reduction in the mean number of CH attacks per week. Response rate, abortive medication use and safety/tolerability were also assessed. RESULTS: During the randomised phase, individuals in the intent-to-treat population treated with SoC plus nVNS (n = 45) had a significantly greater reduction in the number of attacks per week vs controls (n = 48) (-5.9 vs -2.1, respectively) for a mean therapeutic gain of 3.9 fewer attacks per week (95% CI: 0.5, 7.2; p = 0.02). Higher ≥50% response rates were also observed with SoC plus nVNS (40% (18/45)) vs controls (8.3% (4/48); p < 0.001). No serious treatment-related adverse events occurred. CONCLUSION: Adjunctive prophylactic nVNS is a well-tolerated novel treatment for chronic CH, offering clinical benefits beyond those with SoC.
Assuntos
Cefaleia Histamínica/terapia , Estimulação do Nervo Vago/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: To report a rare case of bilateral optic disc edema as presentation of an obstructing spinal plasmacytoma. METHODS: Case report. RESULTS: A 41-year-old healthy man presented with distortion of his peripheral vision for 9 months. He denied headaches or neurologic symptoms. Examination showed bilateral optic disc swelling, radial disc hemorrhages, and absent spontaneous venous pulsations. Brain magnetic resonance imaging (MRI) and magnetic resonance venography were unrevealing. Lumbar puncture showed a normal opening pressure of 19 cm cerebrospinal fluid (CSF). CSF protein was significantly elevated at 3.22 g/L (0.10-0.45 g/L). Spinal MRI with contrast revealed a tumor in the T9 vertebral body extending through the disc spaces into T8 and T10, compressing the spinal cord. Computed tomography-guided biopsy confirmed a spinal plasmacytoma. He received radiotherapy to the spine T7-T11 to reduce spinal cord compression followed by a 6-month course of chemotherapy with dexamethasone, cyclophosphamide, and thalidomide. Disc swelling improved on starting radiotherapy with complete resolution 8 months posttreatment. MRI spine showed reduction of tumor. CONCLUSIONS: This case highlights the importance of spinal imaging in patients with normal cranial scans and raised CSF protein levels who lack the typical idiopathic intracranial hypertension phenotype.
Assuntos
Líquido Cefalorraquidiano , Papiledema/diagnóstico , Plasmocitoma/diagnóstico , Pseudotumor Cerebral/diagnóstico , Compressão da Medula Espinal/diagnóstico , Neoplasias da Coluna Vertebral/diagnóstico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Proteínas do Líquido Cefalorraquidiano/metabolismo , Terapia Combinada , Humanos , Pressão Intracraniana , Imageamento por Ressonância Magnética , Masculino , Papiledema/etiologia , Papiledema/terapia , Plasmocitoma/complicações , Plasmocitoma/terapia , Pseudotumor Cerebral/terapia , Radioterapia Adjuvante , Compressão da Medula Espinal/terapia , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/terapia , Vértebras Torácicas , Tomografia de Coerência Óptica , Tomografia Computadorizada por Raios XRESUMO
Epigenetic marks such as cytosine methylation are important determinants of cellular and whole-body phenotypes. However, the extent of, and reasons for inter-individual differences in cytosine methylation, and their association with phenotypic variation are poorly characterised. Here we present the first genome-wide study of cytosine methylation at single-nucleotide resolution in an animal model of human disease. We used whole-genome bisulfite sequencing in the spontaneously hypertensive rat (SHR), a model of cardiovascular disease, and the Brown Norway (BN) control strain, to define the genetic architecture of cytosine methylation in the mammalian heart and to test for association between methylation and pathophysiological phenotypes. Analysis of 10.6 million CpG dinucleotides identified 77,088 CpGs that were differentially methylated between the strains. In F1 hybrids we found 38,152 CpGs showing allele-specific methylation and 145 regions with parent-of-origin effects on methylation. Cis-linkage explained almost 60% of inter-strain variation in methylation at a subset of loci tested for linkage in a panel of recombinant inbred (RI) strains. Methylation analysis in isolated cardiomyocytes showed that in the majority of cases methylation differences in cardiomyocytes and non-cardiomyocytes were strain-dependent, confirming a strong genetic component for cytosine methylation. We observed preferential nucleotide usage associated with increased and decreased methylation that is remarkably conserved across species, suggesting a common mechanism for germline control of inter-individual variation in CpG methylation. In the RI strain panel, we found significant correlation of CpG methylation and levels of serum chromogranin B (CgB), a proposed biomarker of heart failure, which is evidence for a link between germline DNA sequence variation, CpG methylation differences and pathophysiological phenotypes in the SHR strain. Together, these results will stimulate further investigation of the molecular basis of locally regulated variation in CpG methylation and provide a starting point for understanding the relationship between the genetic control of CpG methylation and disease phenotypes.
Assuntos
Doenças Cardiovasculares/genética , Metilação de DNA , Genoma , Miocárdio/metabolismo , Animais , Sequência de Bases , Doenças Cardiovasculares/patologia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Masculino , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Polimorfismo de Nucleotídeo Único , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos SHR , Análise de Sequência de DNA/métodosRESUMO
HMIP-2 is a human quantitative trait locus affecting peripheral numbers, size and hemoglobin composition of red blood cells, with a marked effect on the persistence of the fetal form of hemoglobin, HbF, in adults. The locus consists of multiple common variants in an enhancer region for MYB (chr 6q23.3), which encodes the hematopoietic transcription factor cMYB. Studying a European population cohort and four African-descended groups of patients with sickle cell anemia, we found that all share a set of two spatially separate HbF-promoting alleles at HMIP-2, termed "A" and "B." These typically occurred together ("A-B") on European chromosomes, but existed on separate homologous chromosomes in Africans. Using haplotype signatures for "A" and "B," we interrogated public population datasets. Haplotypes carrying only "A" or "B" were typical for populations in Sub-Saharan Africa. The "A-B" combination was frequent in European, Asian, and Amerindian populations. Both alleles were infrequent in tropical regions, possibly undergoing negative selection by geographical factors, as has been reported for malaria with other hematological traits. We propose that the ascertainment of worldwide distribution patterns for common, HbF-promoting alleles can aid their further genetic characterization, including the investigation of gene-environment interaction during human migration and adaptation.
Assuntos
Anemia Falciforme/genética , Elementos Facilitadores Genéticos , Eritrócitos/citologia , Locos de Características Quantitativas , Alelos , População Negra/genética , Interação Gene-Ambiente , Estudos de Associação Genética , Genética Populacional , Genoma Humano , Genótipo , Haplótipos , Humanos , Proteínas Proto-Oncogênicas c-myb/genética , Análise de Sequência de DNA , População Branca/genéticaRESUMO
Clinical diagnosis of amyotrophic lateral sclerosis (ALS) in patients presenting with cramps and fasciculations may not be evident at the first consultation. Sequential reviews, clinical and neurophysiological, form an important part of clinical practice in such cases. Recent attempts to delineate a more benign group with cramps and fasciculations have lacked information on the long term profile, both clinical and neurophysiological. Four patients who were initially diagnosed as suffering from benign cramps and fasciculations, but who subsequently progressed to ALS, are described. We propose that a diagnosis of benign cramps and fasciculations should not be considered secure without a minimum follow up of 4-5 years.
Assuntos
Esclerose Lateral Amiotrófica/complicações , Fasciculação/etiologia , Cãibra Muscular/etiologia , Adulto , Progressão da Doença , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-IdadeRESUMO
Cytotoxic precipitation of free α-globin monomers and its production of reactive oxygen species cause red cell membrane damage that leads to anemia and eventually ineffective erythropoiesis in ß-thalassemia. Alpha hemoglobin stabilizing protein (AHSP) was found to bind only to free α-globin monomers creating a stable and inert complex which remains soluble in the cytoplasm thus preventing harmful precipitations. Alpha hemoglobin stabilizing protein was shown to bind nascent α-globin monomers with transient strength before transferring α-globin to ß-globin to form hemoglobin tetramer. A classical twin study would be beneficial to investigate the role of genetics and environment in the variation of alpha hemoglobin stabilizing protein expression as this knowledge will enable us to determine further investigations with regards to therapeutic interventions if alpha hemoglobin stabilizing protein is to be a therapeutic agent for ß-thalassemia. This study investigates the heritability influence of alpha hemoglobin stabilizing protein expression and factors that may contribute to this. Results indicated that a major proportion of alpha hemoglobin stabilizing protein expression was influenced by genetic heritability (46%) with cis-acting factors accounting for 19% and trans-acting factors at 27%.
Assuntos
Proteínas Sanguíneas/genética , Doenças em Gêmeos/genética , Regulação da Expressão Gênica , Predisposição Genética para Doença/genética , Chaperonas Moleculares/genética , Talassemia beta/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , RNA Mensageiro/genética , Elementos Reguladores de Transcrição/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto JovemRESUMO
INTRODUCTION: Chronic tension-type headache (CTTH) is a disorder that evolves from episodic tension-type headache, with daily or very frequent episodes of headache lasting minutes to days. It affects 4.1% of the general population in the USA, and is more prevalent in women (up to 65% of cases). METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments for chronic tension-type headache? What are the effects of non-drug treatments for chronic tension-type headache? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2007 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). RESULTS: We found 50 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. CONCLUSIONS: In this systematic review, we present information relating to the effectiveness and safety of the following interventions: acupuncture; amitriptyline; analgesics; anticonvulsant drugs; benzodiazepines; botulinum toxin; chiropractic and osteopathic manipulations; cognitive behavioural therapy (CBT); Indian head massage; mirtazapine; relaxation and electromyographic biofeedback; selective serotonin reuptake inhibitor antidepressants (SSRIs); and tricyclic antidepressants (other than amitriptyline).
Assuntos
Cefaleia , Cefaleia do Tipo Tensional , Amitriptilina/uso terapêutico , Cefaleia/tratamento farmacológico , Humanos , Osteopatia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Cefaleia do Tipo Tensional/tratamento farmacológicoRESUMO
INTRODUCTION: Subarachnoid haemorrhage (SAH) may arise spontaneously or as a result of trauma. Spontaneous SAH accounts for about 5% of all strokes. Ruptured aneurysms are the cause of 85% of spontaneous SAH. The most characteristic clinical feature is sudden-onset severe headache. Other features include vomiting, photophobia, and focal neurological deficit or seizures, or both. As the headache may have insidious onset in some cases, or may even be absent, a high degree of suspicion is required to diagnose SAH with less typical presentations. METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of surgical treatments for people with confirmed aneurysmal subarachnoid haemorrhage? What are the effects of medical treatments to prevent delayed cerebral ischaemia in people with confirmed aneurysmal subarachnoid haemorrhage? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2009 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). RESULTS: We found 6 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. CONCLUSIONS: In this systematic review we present information relating to the effectiveness and safety of the following interventions: endovascular coiling; surgical clipping; timing of surgery; and oral and intravenous nimodipine.
Assuntos
Aneurisma Roto , Hemorragia Subaracnóidea , Doença Aguda , Administração Oral , Aneurisma Roto/cirurgia , Humanos , Hemorragia Subaracnóidea/diagnóstico , Instrumentos CirúrgicosRESUMO
BACKGROUND: Real-time PCR is a reliable tool with which to measure mRNA transcripts, and provides valuable information on gene expression profiles. Endogenous controls such as housekeeping genes are used to normalise mRNA levels between samples for sensitive comparisons of mRNA transcription. Selection of the most stable control gene(s) is therefore critical for the reliable interpretation of gene expression data. For the purpose of this study, 7 commonly used housekeeping genes were investigated in salivary submandibular glands under normal, inflamed, atrophic and regenerative states. RESULTS: The program NormFinder identified the suitability of HPRT to use as a single gene for normalisation within the normal, inflamed and regenerative states, and GAPDH in the atrophic state. For normalisation to multiple housekeeping genes, for each individual state, the optimal number of housekeeping genes as given by geNorm was: ACTB/UBC in the normal, ACTB/YWHAZ in the inflamed, ACTB/HPRT in the atrophic and ACTB/GAPDH in the regenerative state. The most stable housekeeping gene identified between states (compared to normal) was UBC. However, ACTB, identified as one of the most stably expressed genes within states, was found to be one of the most variable between states. Furthermore we demonstrated that normalising between states to ACTB, rather than UBC, introduced an approximately 3 fold magnitude of error. CONCLUSION: Using NormFinder, our studies demonstrated the suitability of HPRT to use as a single gene for normalisation within the normal, inflamed and regenerative groups and GAPDH in the atrophic group. However, if normalising to multiple housekeeping genes, we recommend normalising to those identified by geNorm. For normalisation across the physiological states, we recommend the use of UBC.