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1.
J Neurol ; 271(6): 3648-3652, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38478031

RESUMO

BACKGROUND AND OBJECTIVE: Primary angiitis of the central nervous system (PACNS) is a rare form of vasculitis solely affecting the vessels of the brain, spinal cord, and leptomeninges. A range of magnetic resonance imaging (MRI) features have been associated with PACNS, including cerebral infarction, hemorrhage, and parenchymal or leptomeningeal contrast enhancement. METHODS AND RESULTS: We describe a 51-year-old man with a case of PACNS manifesting as akinetic mutism with progressive leukoencephalopathy. DISCUSSION: Progressive leukoencephalopathy has not been well defined as a manifestation of PACNS. We review a small number of cases with comparable features, providing additional context on this PACNS manifestation with consideration of clinical subtypes.


Assuntos
Leucoencefalopatias , Vasculite do Sistema Nervoso Central , Humanos , Masculino , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Leucoencefalopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Vasculite do Sistema Nervoso Central/complicações
2.
J Neuroimmunol ; 372: 577967, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36126373

RESUMO

Transverse myelitis is a subacute immune mediated myelopathy secondary to a range of conditions. Post infectious transverse myelitis can be seen with several infectious etiologies. Myelin oligodendrocyte glycoprotein associated disease (MOGAD) is a relatively recently defined condition frequently manifesting with longitudinally extensive transverse myelitis. Cases of MOGAD have occurred after infection, typically respiratory tract infections. We report an unusual case of MOGAD transverse myelitis following a streptococcal brain abscess which has not been previously reported.


Assuntos
Abscesso Encefálico , Mielite Transversa , Mielite , Autoanticorpos , Abscesso Encefálico/complicações , Abscesso Encefálico/etiologia , Humanos , Glicoproteína Mielina-Oligodendrócito , Mielite Transversa/diagnóstico por imagem , Mielite Transversa/etiologia
3.
J Neurol Sci ; 431: 120042, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740019

RESUMO

BACKGROUND: Autoimmune encephalitis (AIE) encompasses a range of inflammatory disorders manifesting with some combination of encephalopathy, seizures, behavioral changes, movement disorders, dysautonomia or other neurologic symptoms. Anti-N-methyl-d-aspartate receptor encephalitis (NMDARE) is the most common AIE and is an autoantibody mediated disorder, often paraneoplastic. Untreated or undertreated AIE has a high degree of morbidity and mortality. Immunosuppressive treatment regimens including glucocorticoids, plasma exchange (PLEX), intravenous immunoglobulin (IVIG) and rituximab used alone or in combination for such patients. Patients' refractory to such treatments requires more aggressive and potentially toxic therapies. We report favorable outcomes in patients with refractory AIE who received intrathecal methotrexate (IT-MTX) as part of treatment. METHODS: Cases at our institution seen between 2010 and 2020 were reviewed. We identified 5 patients in our clinical practice whose clinical presentation was compatible with NMDARE. Three patients met criteria for definite NMDARE. An additional two patients met criteria for probable NMDARE in the acute setting but were ultimately seronegative autoimmune encephalitis. All patients received at least one dose of IT-MTX after failing conventional therapies. At the time of IT-MTX administration patients were catatonic, comatose, or severely encephalopathic despite initial treatments. RESULTS: All patients were treated with methylprednisolone; 3 received a course of IVIG, 4 underwent PLEX, and 4 received rituximab. At the time IT-MTX was given, three patients required mechanical ventilation and 1 had a pacemaker placed for autonomic failure. Two patients were under consideration for transition to palliative care. All patients improved and were at or near their premorbid baseline at last follow-up. All patients tolerated IT-MTX well. CONCLUSIONS: This retrospective review demonstrates the efficacy of intrathecal methotrexate in the treatment of severe AIE who had failed other immunosuppressive regimens.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Metotrexato , Encefalite Antirreceptor de N-Metil-D-Aspartato/tratamento farmacológico , Humanos , Terapia de Imunossupressão , Metotrexato/uso terapêutico , Receptores de N-Metil-D-Aspartato , Estudos Retrospectivos
5.
JAMA Neurol ; 77(11): 1420-1429, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32744608

RESUMO

Importance: Recognizing the presenting and immunopathological features of Kelch-like protein-11 immunoglobulin G seropositive (KLHL11 IgG+) patients may aid in early diagnosis and management. Objective: To describe expanding neurologic phenotype, cancer associations, outcomes, and immunopathologic features of KLHL11 encephalitis. Design, Setting, and Participants: This retrospective tertiary care center study, conducted from October 15, 1998, to November 1, 2019, prospectively identified 31 KLHL11 IgG+ cases in the neuroimmunology laboratory. Eight were identified by retrospective testing of patients with rhomboencephalitis (confirmed by tissue-based-immunofluorescence and transfected-cell-based assays). Main Outcomes and Measures: Outcome variables included modified Rankin score and gait aid use. Results: All 39 KLHL11 IgG+ patients were men (median age, 46 years; range, 28-73 years). Initial clinical presentations were ataxia (n = 32; 82%), diplopia (n = 22; 56%), vertigo (n = 21; 54%), hearing loss (n = 15; 39%), tinnitus (n = 14; 36%), dysarthria (n = 11; 28%), and seizures (n = 9; 23%). Atypical neurologic presentations included neuropsychiatric dysfunction, myeloneuropathy, and cervical amyotrophy. Hearing loss or tinnitus preceded other neurologic deficits by 1 to 8 months in 10 patients (26%). Among patients screened for malignancy (n = 36), testicular germ-cell tumors (n = 23; 64%) or testicular microlithiasis and fibrosis concerning for regressed germ cell tumor (n = 7; 19%) were found in 83% of the patients (n = 30). In 2 patients, lymph node biopsy diagnosed metastatic lung adenocarcinoma in one and chronic lymphocytic leukemia in the other. Initial brain magnetic resonance imaging revealed T2 hyperintensities in the temporal lobe (n = 12), cerebellum (n = 9), brainstem (n = 3), or diencephalon (n = 3). Among KLHL11 IgG+ patients who underwent HLA class I and class II genotyping (n = 10), most were found to have HLA-DQB1*02:01 (n = 7; 70%) and HLA-DRB1*03:01 (n = 6; 60%) associations. A biopsied gadolinium-enhancing temporal lobe lesion demonstrated T cell-predominant inflammation and nonnecrotizing granulomas. Cerebellar biopsy (patient with chronic ataxia) and 2 autopsied brains demonstrated Purkinje neuronal loss and Bergmann gliosis, supporting early active inflammation and later extensive neuronal loss. Compared with nonautoimmune control peripheral blood mononuclear cells, cluster of differentiation (CD) 8+ and CD4+ T cells were significantly activated when patient peripheral blood mononuclear cells were cultured with KLHL11 protein. Most patients (58%) benefitted from immunotherapy and/or cancer treatment (neurological disability stabilized [n = 10] or improved [n = 9]). Kaplan-Meier curve demonstrated significantly higher probability of wheelchair dependence among patients without detectable testicular cancer. Long-term outcomes in KLHL11-IgG+ patients were similar to Ma2 encephalitis. Conclusions and Relevance: Kelch-like protein-11 IgG is a biomarker of testicular germ-cell tumor and paraneoplastic neurologic syndrome, often refractory to treatment. Described expanded neurologic phenotype and paraclinical findings may aid in its early diagnosis and treatment.


Assuntos
Autoanticorpos/sangue , Proteínas de Transporte/sangue , Encefalite/sangue , Síndromes Paraneoplásicas do Sistema Nervoso/sangue , Fenótipo , Adulto , Idoso , Autoanticorpos/imunologia , Biomarcadores/sangue , Proteínas de Transporte/imunologia , Encefalite/diagnóstico , Encefalite/imunologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Paraneoplásicas do Sistema Nervoso/diagnóstico , Síndromes Paraneoplásicas do Sistema Nervoso/imunologia , Estudos Retrospectivos , Linfócitos T/imunologia , Linfócitos T/metabolismo
6.
J Biol Chem ; 295(32): 10926-10939, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32471866

RESUMO

Chemokines mediate leukocyte migration and homeostasis and are key targets in inflammatory diseases including atherosclerosis, cytokine storm, and chronic autoimmune disease. Chemokine redundancy and ensuing network robustness has frustrated therapeutic development. Salivary evasins from ticks bind multiple chemokines to overcome redundancy and are effective in several preclinical disease models. Their clinical development has not progressed because of concerns regarding potential immunogenicity, parenteral delivery, and cost. Peptides mimicking protein activity can overcome the perceived limitations of therapeutic proteins. Here we show that peptides possessing multiple chemokine-binding and anti-inflammatory activities can be developed from the chemokine-binding site of an evasin. We used hydrogen-deuterium exchange MS to map the binding interface of the evasin P672 that physically interacts with C-C motif chemokine ligand (CCL) 8 and synthesized a 16-mer peptide (BK1.1) based on this interface region in evasin P672. Fluorescent polarization and native MS approaches showed that BK1.1 binds CCL8, CCL7, and CCL18 and disrupts CCL8 homodimerization. We show that a BK1.1 derivative, BK1.3, has substantially improved ability to disrupt P672 binding to CCL8, CCL2, and CCL3 in an AlphaScreen assay. Using isothermal titration calorimetry, we show that BK1.3 directly binds CCL8. BK1.3 also has substantially improved ability to inhibit CCL8, CCL7, CCL2, and CCL3 chemotactic function in vitro We show that local as well as systemic administration of BK1.3 potently blocks inflammation in vivo Identification and characterization of the chemokine-binding interface of evasins could thus inspire the development of novel anti-inflammatory peptides that therapeutically target the chemokine network in inflammatory diseases.


Assuntos
Anti-Inflamatórios/química , Quimiocina CCL8/metabolismo , Peptídeos/química , Engenharia de Proteínas , Receptores de Quimiocinas/metabolismo , Sequência de Aminoácidos , Animais , Anti-Inflamatórios/farmacologia , Dimerização , Humanos , Espectrometria de Massas/métodos , Peptídeos/farmacologia , Ligação Proteica , Homologia de Sequência de Aminoácidos , Carrapatos/metabolismo
7.
J Biol Chem ; 294(29): 11199-11212, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31167786

RESUMO

Tick evasins (EVAs) bind either CC- or CXC-chemokines by a poorly understood promiscuous or "one-to-many" mechanism to neutralize inflammation. Because EVAs potently inhibit inflammation in many preclinical models, highlighting their potential as biological therapeutics for inflammatory diseases, we sought to further unravel the CXC-chemokine-EVA interactions. Using yeast surface display, we identified and characterized 27 novel CXC-chemokine-binding evasins homologous to EVA3 and defined two functional classes. The first, which included EVA3, exclusively bound ELR+ CXC-chemokines, whereas the second class bound both ELR+ and ELR- CXC-chemokines, in several cases including CXC-motif chemokine ligand 10 (CXCL10) but, surprisingly, not CXCL8. The X-ray crystal structure of EVA3 at a resolution of 1.79 Å revealed a single antiparallel ß-sheet with six conserved cysteine residues forming a disulfide-bonded knottin scaffold that creates a contiguous solvent-accessible surface. Swapping analyses identified distinct knottin scaffold segments necessary for different CXC-chemokine-binding activities, implying that differential ligand positioning, at least in part, plays a role in promiscuous binding. Swapping segments also transferred chemokine-binding activity, resulting in a hybrid EVA with dual CXCL10- and CXCL8-binding activities. The solvent-accessible surfaces of the knottin scaffold segments have distinctive shape and charge, which we suggest drives chemokine-binding specificity. These studies provide structural and mechanistic insight into how CXC-chemokine-binding tick EVAs achieve class specificity but also engage in promiscuous binding.


Assuntos
Quimiocinas CXC/metabolismo , Miniproteínas Nó de Cistina/metabolismo , Receptores de Quimiocinas/metabolismo , Carrapatos/metabolismo , Animais , Cristalografia por Raios X , Ligação Proteica , Conformação Proteica , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/isolamento & purificação , Especificidade da Espécie , Carrapatos/classificação , Leveduras/genética
8.
FASEB J ; 33(1): 652-667, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30028636

RESUMO

Lipin 1 regulates glycerolipid homeostasis by acting as a phosphatidic acid phosphohydrolase (PAP) enzyme in the triglyceride-synthesis pathway and by regulating transcription factor activity. Mutations in human lipin 1 are a common cause of recurrent rhabdomyolysis in children. Mice with constitutive whole-body lipin 1 deficiency have been used to examine mechanisms connecting lipin 1 deficiency to myocyte injury. However, that mouse model is confounded by lipodystrophy not phenocopied in people. Herein, 2 muscle-specific mouse models were studied: 1) Lpin1 exon 3 and 4 deletion, resulting in a hypomorphic protein without PAP activity, but which preserved transcriptional coregulatory function; and 2) Lpin1 exon 7 deletion, resulting in total protein loss. In both models, skeletal muscles exhibited a chronic myopathy with ongoing muscle fiber necrosis and regeneration and accumulation of phosphatidic acid and, paradoxically, diacylglycerol. Additionally, lipin 1-deficient mice had abundant, but abnormal, mitochondria likely because of impaired autophagy. Finally, these mice exhibited increased plasma creatine kinase following exhaustive exercise when unfed. These data suggest that mice lacking lipin 1-mediated PAP activity in skeletal muscle may serve as a model for determining the mechanisms by which lipin 1 deficiency leads to myocyte injury and for testing potential therapeutic approaches.-Schweitzer, G. G., Collier, S. L., Chen, Z., McCommis, K. S., Pittman, S. K., Yoshino, J., Matkovich, S. J., Hsu, F.-F., Chrast, R., Eaton, J. M., Harris, T. E., Weihl, C. C., Finck, B. N. Loss of lipin 1-mediated phosphatidic acid phosphohydrolase activity in muscle leads to skeletal myopathy in mice.


Assuntos
Modelos Animais de Doenças , Regulação da Expressão Gênica , Músculo Esquelético/patologia , Doenças Musculares/patologia , Proteínas Nucleares/fisiologia , Fosfatidato Fosfatase/metabolismo , Ácidos Fosfatídicos/metabolismo , Animais , Autofagia , Feminino , Perfilação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Doenças Musculares/etiologia , Doenças Musculares/metabolismo , Fosfatidato Fosfatase/genética , Fosfatidato Fosfatase/fisiologia
9.
Clinicoecon Outcomes Res ; 9: 505-518, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28860832

RESUMO

BACKGROUND: Comparative effectiveness and cost-effectiveness data for induction-maintenance (I-M) sequences for the treatment of patients with nonsquamous non-small-cell lung cancer (nsqNSCLC) are limited because of a lack of direct evidence. This analysis aimed to compare the cost-effectiveness of I-M pemetrexed with those of other I-M regimens used for the treatment of patients with advanced nsqNSCLC in the French health-care setting. MATERIALS AND METHODS: A previously developed global partitioned survival model was adapted to the France-only setting by restricting treatment sequences to include 12 I-M regimens most relevant to France, and incorporating French costs and resource-use data. Following a systematic literature review, network meta-analyses were performed to obtain hazard ratios for progression-free survival (PFS) and overall survival (OS) relative to gemcitabine + cisplatin (induction sequences) or best supportive care (BSC) (maintenance sequences). Modeled health-care benefits were expressed as life-years (LYs) and quality-adjusted LYs (QALYs) (estimated using French EuroQol five-dimension questionnaire tariffs). The study was conducted from the payer perspective (National Health Insurance). Cost- and benefit-model inputs were discounted at an annual rate of 4%. RESULTS: Base-case results showed pemetrexed + cisplatin induction followed by (→) pemetrexed maintenance had the longest mean OS and PFS and highest LYs and QALYs. Costs ranged from €12,762 for paclitaxel + carboplatin → BSC to €35,617 for pemetrexed + cisplatin → pemetrexed (2015 values). Gemcitabine + cisplatin → BSC, pemetrexed + cisplatin → BSC, and pemetrexed + cisplatin → pemetrexed were associated with fully incremental cost-effectiveness ratios (ICERs) of €16,593, €80,656, and €102,179, respectively, per QALY gained versus paclitaxel + carboplatin → BSC. All other treatment sequences were either dominated (ie, another sequence had lower costs and better/equivalent outcomes) or extendedly dominated (ie, the comparator had a higher ICER than a more effective comparator) in the model. Sensitivity analyses showed the model to be relatively insensitive to plausible changes in the main assumptions, with none increasing or decreasing the ICER by more than ~€20,000 per QALY gained. CONCLUSION: In the absence of direct comparative trial evidence, this cost-effectiveness analysis indicated that of a large number of I-M sequences used for the treatment of patients with nsqNSCLC in France, pemetrexed + cisplatin → pemetrexed achieved the best clinical outcomes (0.28 incremental QALYs gained) versus paclitaxel + carboplatin → BSC.

10.
J Med Econ ; 20(1): 8-18, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27472034

RESUMO

OBJECTIVE: To evaluate cost-effectiveness of brentuximab vedotin in patients with relapsed/refractory Hodgkin lymphoma who have received autologous stem cell transplantation, from a Scottish healthcare payer perspective. METHODS: A Microsoft Excel-based partitioned survival model comprising three health states (progression-free survival [PFS], post-progression survival, and death) was developed. Relevant comparators were chemotherapy with or without radiotherapy (C/R) and C/R with intent to allogeneic hematopoietic stem cell transplantation (alloSCT). Data were obtained from the pivotal phase II single-arm trial in 102 patients (SG035-0003; NCT00848926), a systematic literature review and clinical expert opinions (where empirical evidence was unavailable). PFS and overall survival for brentuximab vedotin were estimated using 5-year follow-up data from SG035-0003, and extrapolated using event rates observed for comparator treatments from published survival data. Resource use included drug acquisition and administration; alloSCT; treatment of adverse events; and long-term follow-up. Deterministic and probabilistic sensitivity analyses were conducted to evaluate the impact of uncertainty. RESULTS: In the base case, the incremental cost-effectiveness ratio (ICER) for brentuximab vedotin was £38,769 per quality-adjusted life year (QALY) vs C/R, whereas C/R with intent to alloSCT was dominated by brentuximab vedotin. ICERs for brentuximab vedotin generated by the deterministic sensitivity analysis ranged between £32,000-£54,000 per QALY. Including productivity benefits reduced the ICER to £28,881 per QALY. LIMITATIONS: Limitations include lack of comparative data from this single arm study and the heterogeneous population. Inconsistent baseline characteristic reporting across studies prevented complete assessment of heterogeneity and the extent of potential bias in clinical and cost-effectiveness estimates. CONCLUSIONS: Although the base case ICER is above the threshold usually applied in Scotland, it is relatively low compared with other orphan drugs, and lower than the ICER generated using a previous data cut of SG035-0003 that informed a positive recommendation from the Scottish Medicines Consortium, under its decision-making framework for assessment of ultra-orphan medicines.


Assuntos
Análise Custo-Benefício , Doença de Hodgkin/cirurgia , Imunoconjugados/economia , Imunoconjugados/uso terapêutico , Transplante Autólogo/economia , Adolescente , Adulto , Idoso , Brentuximab Vedotin , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida , Escócia , Prevenção Secundária , Transplante de Células-Tronco , Adulto Jovem
11.
JIMD Rep ; 23: 113-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25967228

RESUMO

Rhabdomyolysis is an acute syndrome due to extensive injury of skeletal muscle. Recurrent rhabdomyolysis is often caused by inborn errors in intermediary metabolism, and recent work has suggested that mutations in the human gene encoding lipin 1 (LPIN1) may be a common cause of recurrent rhabdomyolysis in children. Lipin 1 dephosphorylates phosphatidic acid to form diacylglycerol (phosphatidic acid phosphohydrolase; PAP) and acts as a transcriptional regulatory protein to control metabolic gene expression. Herein, a 3-year-old boy with severe recurrent rhabdomyolysis was determined to be a compound heterozygote for a novel c.1904T>C (p.Leu635Pro) substitution and a previously reported genomic deletion of exons 18-19 (E766-S838_del) in LPIN1. Western blotting with patient muscle biopsy lysates demonstrated a marked reduction in lipin 1 protein, while immunohistochemical staining for lipin 1 showed abnormal subcellular localization. We cloned cDNAs to express recombinant lipin 1 proteins harboring pathogenic mutations and showed that the E766-S838_del allele was not expressed at the RNA or protein level. Lipin 1 p.Leu635Pro was expressed, but the protein was less stable, was aggregated in the cytosol, and was targeted for proteosomal degradation. Another pathogenic single amino acid substitution, lipin 1 p.Arg725His, was well expressed and retained its transcriptional regulatory function. However, both p.Leu635Pro and p.Arg725His proteins were found to be deficient in PAP activity. Kinetic analyses demonstrated a loss of catalysis rather than diminished substrate binding. These data suggest that loss of lipin 1-mediated PAP activity may be involved in the pathogenesis of rhabdomyolysis in lipin 1 deficiency.

12.
Proc Natl Acad Sci U S A ; 111(49): 17450-5, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25422441

RESUMO

Anabolic and catabolic signaling oppose one another in adipose tissue to maintain cellular and organismal homeostasis, but these pathways are often dysregulated in metabolic disorders. Although it has long been established that stimulation of the ß-adrenergic receptor inhibits insulin-stimulated glucose uptake in adipocytes, the mechanism has remained unclear. Here we report that ß-adrenergic-mediated inhibition of glucose uptake requires lipolysis. We also show that lipolysis suppresses glucose uptake by inhibiting the mammalian target of rapamycin (mTOR) complexes 1 and 2 through complex dissociation. In addition, we show that products of lipolysis inhibit mTOR through complex dissociation in vitro. These findings reveal a previously unrecognized intracellular signaling mechanism whereby lipolysis blocks the phosphoinositide 3-kinase-Akt-mTOR pathway, resulting in decreased glucose uptake. This previously unidentified mechanism of mTOR regulation likely contributes to the development of insulin resistance.


Assuntos
Adipócitos/citologia , Catecolaminas/química , Glucose/farmacocinética , Lipólise/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Células 3T3-L1 , Animais , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Homeostase , Hiperglicemia/metabolismo , Insulina/metabolismo , Resistência à Insulina , Lipídeos/química , Camundongos , Modelos Biológicos , Naftiridinas/metabolismo , Receptores Adrenérgicos beta/metabolismo , Transdução de Sinais
13.
J Med Econ ; 16(11): 1317-26, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24040937

RESUMO

OBJECTIVES: To evaluate the cost-effectiveness of MitraClip, an interventional procedure for patients with chronic severe mitral regurgitation. METHODS: A decision analytic model with a lifetime horizon was developed to assess the cost-effectiveness of MitraClip vs conventional medical management in patients with severe mitral regurgitation, ineligible for surgery. The analysis was performed from a UK NHS perspective and the estimates for mortality, adverse events, and cross-sectional NYHA class were obtained from the EVEREST II High Risk Study (HRS). Utility decrements were obtained from a heath technology assessment on Cardiac Resynchronization Therapy, while unit costs were obtained from national databases. The concept model was clinically validated. Costs (2011 £UK) and benefits were discounted at an annual rate of 3.5%. RESULTS: Compared to medical management, over 2- and 10-year periods MitraClip had incremental Quality Adjusted Life Year (QALY) gains of 0.48 and 2.04, respectively. The Incremental Cost-Effectiveness Ratios for MitraClip at 2 and 10 years are £52,947 and £14,800 per QALY gained. Overall, the model was most sensitive to the choice of time horizon, the discount rate applied to benefits, the starting age of cohort, the utility decrement associated with NYHA II, and cost of the MitraClip procedure. The model was insensitive to changes in all other parameters. MitraClip was also found to be cost-effective, regardless of the modelling approach, and insensitive to the key assumptions of the procedure cost. STUDY LIMITATIONS: The primary limitation of the analysis is the reliance on aggregate data from a modestly sized non-randomized study with a short-term follow-up period. Aligned to this was the need to extrapolate survival well beyond the study period in order to generate meaningful results. The impact of both of these limitations was explored via extensive sensitivity analyses. CONCLUSION: Compared to medical management, MitraClip is a cost-effective interventional procedure at conventional threshold values.


Assuntos
Próteses Valvulares Cardíacas/economia , Insuficiência da Valva Mitral/cirurgia , Fatores Etários , Doença Crônica , Análise Custo-Benefício , Estudos Transversais , Humanos , Cadeias de Markov , Anos de Vida Ajustados por Qualidade de Vida , Índice de Gravidade de Doença , Fatores de Tempo , Reino Unido
14.
Biochemistry ; 51(50): 9966-83, 2012 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-23190562

RESUMO

Biological membranes are exposed to a number of chemical and physical stresses that may alter the structure of the lipid bilayer in such a way that the permeability barrier to hydrophilic molecules and ions is degraded. These stresses include amphiphilic molecules involved in metabolism and signaling, highly charged polyamines, membrane-permeating peptides, and mechanical and osmotic stresses. As annexins are known to bind to lipid headgroups in the presence of calcium and increase the order of the bilayer lipids, this study addressed whether this activity of annexins provides a potential benefit to the membrane by protecting the bilayer against disruptions of this nature or can promote restoration of the permeability barrier after damage by such agents. The release of carboxyfluorescein from large unilamellar vesicles composed of lipids characteristically present in the inner leaflet of cell membranes (phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine, and cholesterol) was used to measure membrane permeability. It was determined that in the presence of calcium, annexin A5 reduced the level of baseline leakage from vesicles and reduced or reversed damage due to arachidonic acid, lysophosphatidic acid, lysophosphatidylcholine, diacylglycerol, monoacylglycerol, spermidine, amyloid-ß, amylin, and osmotic shock. Annexin A6 was also able to provide membrane protection in many but not all of these cases. In a cell, it is likely annexins would move to sites of breakdown of the permeability barrier because of the calcium-dependent promotion of the binding of annexins to membranes at sites of calcium entry. Because of the fundamental importance to life of maintaining the permeability barrier of the cell membrane, it is proposed here that this property of annexins may represent a critical, primordial activity that explains their great evolutionary conservation and abundant expression in most cells.


Assuntos
Anexina A5/metabolismo , Anexina A6/metabolismo , Anexinas/fisiologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Peptídeos beta-Amiloides/farmacologia , Ácido Araquidônico/farmacologia , Cálcio/farmacologia , Membrana Celular/química , Diglicerídeos/farmacologia , Fluoresceínas/metabolismo , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/farmacologia , Bicamadas Lipídicas/metabolismo , Lisofosfatidilcolinas/farmacologia , Lisofosfolipídeos/farmacologia , Monoglicerídeos/farmacologia , Pressão Osmótica , Fragmentos de Peptídeos/farmacologia , Espermidina/farmacologia , Lipossomas Unilamelares/metabolismo
15.
Tetrahedron ; 65(22): 4283-4292, 2009 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-20161334

RESUMO

Studies directed at the synthesis of lamellarin G trimethyl ether and ningalin B via vinylogous iminium salt derivatives are described. The successful strategy relies on the formation of a 2,4-disubstituted pyrrole or a 1,2,3,4-tetrasubstituted pyrrole from a vinylogous iminium salt or vinylogous iminium salt derivative. Subsequent transformations of these highly substituted pyrroles lead to efficient and regiocontrolled formal syntheses of the respective pyrrole containing natural products.

16.
J Steroid Biochem Mol Biol ; 104(3-5): 241-5, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17467271

RESUMO

Gross cystic breast disease is a common benign disorder in which palpable cysts occur in the breast and are normally treated by aspiration of the contents. The cysts are classified as either Type 1, containing a high level of potassium ions and a low level of sodium ions, or as Type 2, with low potassium and high sodium ion concentrations. Steroid sulphatase activity in MDA-MB-231 and MCF-7 cell lines is regulated by exogenous breast cyst fluid (BCF), possibly because of cytokines in the BCF. A screening method was used to determine the range of cytokines in eight BCFs, four of each type. This was an array system, which uses antibodies immobilised on a membrane to qualitatively detect 79 different cytokines or growth factors. Nine cytokines were detected well above background levels: all were found in both types of BCF, but only epidermal growth factor (EGF) was higher in Type 1. All the other factors were higher in Type 2 BCF. Two of these cytokines, IL-6 and EGF, have previously been suggested to affect steroid sulphatase expression and several (MIP-1beta, IL-8, NAP-2) are known to affect MCF-7 cell chemotaxis. In addition two cytokines were measured by ELISA in 57 BCFs, and both IL-1beta and IL-13 were found in BCF, with significantly higher amounts of IL-1beta in Type 1 than Type 2 BCF (35.5+/-4.4 pg/ml versus 9.9+/-2.9 pg/ml).


Assuntos
Cisto Mamário/química , Citocinas/análise , Doença da Mama Fibrocística/patologia , Análise Serial de Proteínas/métodos , Líquido Cístico/química , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-13/análise , Interleucina-1beta/análise
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