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1.
Proc Natl Acad Sci U S A ; 119(2)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34996870

RESUMO

Fate and behavior of neural progenitor cells are tightly regulated during mammalian brain development. Metabolic pathways, such as glycolysis and oxidative phosphorylation, that are required for supplying energy and providing molecular building blocks to generate cells govern progenitor function. However, the role of de novo lipogenesis, which is the conversion of glucose into fatty acids through the multienzyme protein fatty acid synthase (FASN), for brain development remains unknown. Using Emx1Cre-mediated, tissue-specific deletion of Fasn in the mouse embryonic telencephalon, we show that loss of FASN causes severe microcephaly, largely due to altered polarity of apical, radial glia progenitors and reduced progenitor proliferation. Furthermore, genetic deletion and pharmacological inhibition of FASN in human embryonic stem cell-derived forebrain organoids identifies a conserved role of FASN-dependent lipogenesis for radial glia cell polarity in human brain organoids. Thus, our data establish a role of de novo lipogenesis for mouse and human brain development and identify a link between progenitor-cell polarity and lipid metabolism.


Assuntos
Encéfalo/metabolismo , Ácido Graxo Sintases/metabolismo , Lipogênese/fisiologia , Animais , Padronização Corporal , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Ácido Graxo Sintase Tipo I , Ácido Graxo Sintases/genética , Humanos , Metabolismo dos Lipídeos , Lipogênese/genética , Camundongos , Camundongos Knockout , Células-Tronco Neurais/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Transcriptoma
2.
Am J Pathol ; 193(12): 2144-2155, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37741454

RESUMO

Mechanisms responsible for the pathogenesis of diabetic retinal disease remain incompletely understood, but they likely involve multiple cellular targets, including photoreceptors. Evidence suggests that dysregulated de novo lipogenesis in photoreceptors is a critical early target of diabetes. Following on this observation, the present study aimed to determine whether two interventions shown to improve diabetic retinopathy in mice-pharmacologic visual cycle inhibition and prolonged dark adaptation-reduce photoreceptor anabolic lipid metabolism. Elevated retinal lipid biosynthetic signaling was observed in two mouse models of diabetes, with both models showing reduced retinal AMP-activated kinase (AMPK) signaling, elevated acetyl CoA carboxylase (ACC) signaling, and increased activity of fatty acid synthase, which promotes lipotoxicity in photoreceptors. Although retinal AMPK-ACC axis signaling was dependent on systemic glucose fluctuations in healthy animals, mice with diabetes lacked such regulation. Visual cycle inhibition and prolonged dark adaptation reversed abnormal retinal AMPK-ACC signaling in mice with diabetes. Although visual cycle inhibition reduced the severity of diabetic retinopathy in control mice, as assessed by retinal capillary atrophy, this intervention was ineffective in fatty acid synthase gain-of-function mice. These results suggest that early diabetic retinopathy is characterized by glucose-driven elevations in retinal lipid biosynthetic activity, and that two interventions known to increase photoreceptor glucose demands alleviate disease by reversing these signals.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Degeneração Retiniana , Camundongos , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Retinopatia Diabética/metabolismo , Glucose , Ácido Graxo Sintases , Lipídeos
3.
J Biol Chem ; 297(3): 101104, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34425110

RESUMO

Diabetic retinopathy (DR) is an increasingly frequent cause of blindness across populations; however, the events that initiate pathophysiology of DR remain elusive. Strong preclinical and clinical evidence suggests that abnormalities in retinal lipid metabolism caused by diabetes may account for the origin of this disease. A major arm of lipid metabolism, de novo biosynthesis, is driven by elevation in available glucose, a common thread binding all forms of vision loss in diabetes. Therefore, we hypothesized that aberrant retinal lipid biogenesis is an important promoter of early DR. In murine models, we observed elevations of diabetes-associated retinal de novo lipogenesis ∼70% over control levels. This shift was primarily because of activation of fatty acid synthase (FAS), a rate-limiting enzyme in the biogenic pathway. Activation of FAS was driven by canonical glucose-mediated disinhibition of acetyl-CoA carboxylase, a major upstream regulatory enzyme. Mutant mice expressing gain-of-function FAS demonstrated increased vulnerability to DR, whereas those with FAS deletion in rod photoreceptors maintained preserved visual responses upon induction of diabetes. Excess retinal de novo lipogenesis-either because of diabetes or because of FAS gain of function-was associated with modestly increased levels of palmitate-containing phosphatidylcholine species in synaptic membranes, a finding with as yet uncertain significance. These findings implicate glucose-dependent increases in photoreceptor de novo lipogenesis in the early pathogenesis of DR, although the mechanism of deleterious action of this pathway remains unclear.


Assuntos
Retinopatia Diabética/etiologia , Lipogênese/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Acetil-CoA Carboxilase/metabolismo , Animais , Diabetes Mellitus/metabolismo , Retinopatia Diabética/metabolismo , Ácido Graxo Sintases/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Retina/metabolismo , Retina/patologia
4.
New Dir Child Adolesc Dev ; 2020(171): 107-133, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32657046

RESUMO

Efavirenz (EFV) is a well-known, effective anti-retroviral drug long used in first-line treatment for children and adults with HIV and HIV/AIDS. Due to its narrow window of effective concentrations, between 1 and 4 µg/mL, and neurological side effects at supratherapeutic levels, several investigations into the pharmacokinetics of the drug and its genetic underpinnings have been carried out, primarily with adult samples. A number of studies, however, have examined the genetic influences on the metabolism of EFV in children. Their primary goal has been to shed light on issues of appropriate pediatric dosing, as well as the manifestation of neurotoxic effects of EFV in some children. Although EFV is currently being phased out of use for the treatment of both adults and children, we share this line of research to highlight an important aspect of medical treatment that is relevant to understanding the development of children diagnosed with HIV.


Assuntos
Alcinos , Fármacos Anti-HIV , Benzoxazinas , Desenvolvimento Infantil/efeitos dos fármacos , Ciclopropanos , Citocromo P-450 CYP2B6/genética , Infecções por HIV/tratamento farmacológico , Farmacogenética , Inibidores da Transcriptase Reversa , Alcinos/administração & dosagem , Alcinos/metabolismo , Alcinos/toxicidade , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/metabolismo , Fármacos Anti-HIV/toxicidade , Benzoxazinas/administração & dosagem , Benzoxazinas/metabolismo , Benzoxazinas/toxicidade , Criança , Pré-Escolar , Ciclopropanos/administração & dosagem , Ciclopropanos/metabolismo , Ciclopropanos/toxicidade , Humanos , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/metabolismo , Inibidores da Transcriptase Reversa/toxicidade
5.
N Engl J Med ; 372(17): 1619-28, 2015 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-25901427

RESUMO

BACKGROUND: Alcoholic hepatitis is a clinical syndrome characterized by jaundice and liver impairment that occurs in patients with a history of heavy and prolonged alcohol use. The short-term mortality among patients with severe disease exceeds 30%. Prednisolone and pentoxifylline are both recommended for the treatment of severe alcoholic hepatitis, but uncertainty about their benefit persists. METHODS: We conducted a multicenter, double-blind, randomized trial with a 2-by-2 factorial design to evaluate the effect of treatment with prednisolone or pentoxifylline. The primary end point was mortality at 28 days. Secondary end points included death or liver transplantation at 90 days and at 1 year. Patients with a clinical diagnosis of alcoholic hepatitis and severe disease were randomly assigned to one of four groups: a group that received a pentoxifylline-matched placebo and a prednisolone-matched placebo, a group that received prednisolone and a pentoxifylline-matched placebo, a group that received pentoxifylline and a prednisolone-matched placebo, or a group that received both prednisolone and pentoxifylline. RESULTS: A total of 1103 patients underwent randomization, and data from 1053 were available for the primary end-point analysis. Mortality at 28 days was 17% (45 of 269 patients) in the placebo-placebo group, 14% (38 of 266 patients) in the prednisolone-placebo group, 19% (50 of 258 patients) in the pentoxifylline-placebo group, and 13% (35 of 260 patients) in the prednisolone-pentoxifylline group. The odds ratio for 28-day mortality with pentoxifylline was 1.07 (95% confidence interval [CI], 0.77 to 1.49; P=0.69), and that with prednisolone was 0.72 (95% CI, 0.52 to 1.01; P=0.06). At 90 days and at 1 year, there were no significant between-group differences. Serious infections occurred in 13% of the patients treated with prednisolone versus 7% of those who did not receive prednisolone (P=0.002). CONCLUSIONS: Pentoxifylline did not improve survival in patients with alcoholic hepatitis. Prednisolone was associated with a reduction in 28-day mortality that did not reach significance and with no improvement in outcomes at 90 days or 1 year. (Funded by the National Institute for Health Research Health Technology Assessment program; STOPAH EudraCT number, 2009-013897-42 , and Current Controlled Trials number, ISRCTN88782125 ).


Assuntos
Glucocorticoides/uso terapêutico , Hepatite Alcoólica/tratamento farmacológico , Pentoxifilina/uso terapêutico , Prednisolona/uso terapêutico , Adulto , Análise de Variância , Método Duplo-Cego , Feminino , Glucocorticoides/efeitos adversos , Hepatite Alcoólica/mortalidade , Humanos , Infecções/etiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Pentoxifilina/efeitos adversos , Inibidores de Fosfodiesterase/efeitos adversos , Inibidores de Fosfodiesterase/uso terapêutico , Prednisolona/efeitos adversos , Falha de Tratamento
6.
Dev Dyn ; 245(7): 702-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26890418

RESUMO

We here review the existing evidence linking adult hippocampal neurogenesis and human brain function in physiology and disease. Furthermore, we aim to point out where evidence is missing, highlight current promising avenues of investigation, and suggest future tools and approaches to foster the link between life-long neurogenesis and human brain function. Developmental Dynamics 245:702-709, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Hipocampo/citologia , Hipocampo/fisiologia , Neurogênese/fisiologia , Adulto , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/fisiologia , Hipocampo/metabolismo , Humanos , Neurogênese/genética
7.
Br J Cancer ; 115(4): 420-4, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27434036

RESUMO

BACKGROUND: The addition of cetuximab (CTX) to perioperative chemotherapy (CT) for operable colorectal liver metastases resulted in a shorter progression-free survival. Details of disease progression are described to further inform the primary study outcome. METHODS: A total of 257 KRAS wild-type patients were randomised to CT alone or CT with CTX. Data regarding sites and treatment of progressive disease were obtained for the 109 (CT n=48, CT and CTX n=61) patients with progressive disease at the cut-off date for analysis of November 2012. RESULTS: The liver was the most frequent site of progression (CT 67% (32/48); CT and CTX 66% (40/61)). A higher proportion of patients in the CT and group had multiple sites of progressive disease (CT 8%, 4/48; CT and CTX 23%, 14/61 P=0.04). Further treatment for progressive disease is known for 84 patients of whom 69 received further CT, most frequently irinotecan based. Twenty-two patients, 11 in each arm, received CTX as a further line agent. CONCLUSIONS: Both the distribution of progressive disease and further treatment are as expected for such a cohort. The pattern of disease progression seen is consistent with failure of systemic micrometastatic disease control rather than failure of local disease control following liver surgery.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/patologia , Hepatectomia , Neoplasias Hepáticas/tratamento farmacológico , Metastasectomia , Idoso , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Capecitabina/administração & dosagem , Cetuximab/administração & dosagem , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Irinotecano , Leucovorina/administração & dosagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina
8.
Lancet Oncol ; 15(6): 601-11, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24717919

RESUMO

BACKGROUND: Surgery for colorectal liver metastases results in an overall survival of about 40% at 5 years. Progression-free survival is increased with the addition of oxaliplatin and fluorouracil chemotherapy. The addition of cetuximab to these chemotherapy regimens results in an overall survival advantage in patients with advanced disease who have the KRAS exon 2 wild-type tumour genotype. We aimed to assess the benefit of addition of cetuximab to standard chemotherapy in patients with resectable colorectal liver metastasis. METHODS: Patients with KRAS exon 2 wild-type resectable or suboptimally resectable colorectal liver metastases were randomised in a 1:1 ratio to receive chemotherapy with or without cetuximab before and after liver resection. Randomisation was done using minimisation with factors of surgical centre, poor prognostic tumour (one or more of: ≥ 4 metastases, N2 disease, or poor differentiation of primary tumour), and previous adjuvant treatment with oxaliplatin. Chemotherapy consisted of oxaliplatin 85 mg/m(2) intravenously over 2 h and fluorouracil bolus 400 mg/m(2) intravenously over 5 min, followed by a 46 h infusion of fluorouracil 2400 mg/m(2) repeated every 2 weeks (regimen one) or oxaliplatin 130 mg/m(2) intravenously over 2 h and oral capecitabine 1000 mg/m(2) twice daily on days 1-14 repeated every 3 weeks (regimen two). Patients who had received adjuvant oxaliplatin could receive irinotecan 180 mg/m(2) intravenously over 30 min with fluorouracil instead of oxaliplatin (regimen three). Cetuximab was given as an intravenous dose of 500 mg/m(2) every 2 weeks with regimen one and three or a loading dose of 400 mg/m(2) followed by a weekly infusion of 250 mg/m(2) with regimen two. The primary endpoint was progression-free survival. This is an interim analysis, up to Nov 1, 2012, when the trial was closed, having met protocol-defined futility criteria. This trial is registered, ISRCTN22944367. FINDINGS: 128 KRAS exon 2 wild-type patients were randomised to chemotherapy alone and 129 to chemotherapy with cetuximab between Feb 26, 2007, and Nov 1, 2012. 117 patients in the chemotherapy alone group and 119 in the chemotherapy plus cetuximab group were included in the primary analysis. The median follow-up was 21.1 months (95% CI 12.6-33.8) in the chemotherapy alone group and 19.8 months (12.2-28.7) in the chemotherapy plus cetuximab group. With an overall median follow-up of 20.7 months (95% CI 17.9-25.6) and 123 (58%) of 212 required events observed, progression-free survival was significantly shorter in the chemotherapy plus cetuximab group than in the chemotherapy alone group (14.1 months [95% CI 11.8-15.9] vs 20.5 months [95% CI 16.8-26.7], hazard ratio 1.48, 95% CI 1.04-2.12, p=0.030). The most common grade 3 or 4 adverse events were low neutrophil count (15 [11%] preoperatively in the chemotherapy alone group vs six [4%] in the chemotherapy plus cetuximab group; four [4%] vs eight [8%] postoperatively), embolic events (six [4%] vs eight [6%] preoperatively; two [2%] vs three [3%] postoperatively), peripheral neuropathy (six [4%] vs one [1%] preoperatively; two [2%] vs four [4%] postoperatively), nausea or vomiting (four [3%] vs six [4%] preoperatively; four [4%] vs two [2%] postoperatively), and skin rash (two [1%] vs 21 [15%] preoperatively; 0 vs eight [8%] postoperatively). There were three deaths in the chemotherapy plus cetuximab group (one interstitial lung disease and pulmonary embolism, one bronchopneumonia, and one pulmonary embolism) and one in the chemotherapy alone group (heart failure) that might have been treatment related. INTERPRETATION: Addition of cetuximab to chemotherapy and surgery for operable colorectal liver metastases in KRAS exon 2 wild-type patients results in shorter progression-free survival. Translational investigations to explore the molecular basis for this unexpected interaction are needed but at present the use of cetuximab in this setting cannot be recommended.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Capecitabina , Cetuximab , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Irinotecano , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/tratamento farmacológico , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Modelos de Riscos Proporcionais , Resultado do Tratamento
9.
Dev Biol ; 370(1): 110-24, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22841643

RESUMO

Anterior-posterior (AP) limb patterning is directed by sonic hedgehog (SHH) signaling from the posteriorly located zone of polarizing activity (ZPA). GLI3 and GLI2 are the transcriptional mediators generally utilized in SHH signaling, and each can function as an activator (A) and repressor (R). Although GLI3R has been suggested to be the primary effector of SHH signaling during limb AP patterning, a role for GLI3A or GLI2 has not been fully ruled out, nor has it been determined whether Gli3 plays distinct roles in limb development at different stages. By conditionally removing Gli3 in the limb at multiple different time points, we uncovered four Gli3-mediated functions in limb development that occur at distinct but partially over-lapping time windows: AP patterning of the proximal limb, AP patterning of the distal limb, regulation of digit number and bone differentiation. Furthermore, by removing Gli2 in Gli3 temporal conditional knock-outs, we uncovered an essential role for Gli2 in providing the remaining posterior limb patterning seen in Gli3 single mutants. To test whether GLIAs or GLIRs regulate different aspects of AP limb patterning and/or digit number, we utilized a knock-in allele in which GLI1, which functions solely as an activator, is expressed in place of the bifunctional GLI2 protein. Interestingly, we found that GLIAs contribute to AP patterning specifically in the posterior limb, whereas GLIRs predominantly regulate anterior patterning and digit number. Since GLI3 is a more effective repressor, our results explain why GLI3 is required only for anterior limb patterning and why GLI2 can compensate for GLI3A in posterior limb patterning. Taken together, our data suggest that establishment of a complete range of AP positional identities in the limb requires integration of the spatial distribution, timing, and dosage of GLI2 and GLI3 activators and repressors.


Assuntos
Padronização Corporal/fisiologia , Extremidades/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transdução de Sinais/fisiologia , Animais , Western Blotting , Primers do DNA/genética , Extremidades/anatomia & histologia , Proteínas Hedgehog/metabolismo , Hibridização In Situ , Camundongos , Camundongos Transgênicos , Transdução de Sinais/genética , Tamoxifeno , Proteína Gli2 com Dedos de Zinco , Proteína Gli3 com Dedos de Zinco , beta-Galactosidase/metabolismo
10.
J Cachexia Sarcopenia Muscle ; 14(6): 2473-2497, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37750475

RESUMO

Cancer cachexia (CC) is a multifactorial syndrome driven by inflammation, defined by ongoing loss of skeletal muscle mass (with or without loss of fat mass) that cannot be fully reversed by conventional nutritional support. CC leads to progressive functional impairment, with its clinical management complicated and limited therapeutic options available. The objective of this review was to assess the efficacy and safety of non-steroidal anti-inflammatory drugs (NSAIDs) on patient-centred outcomes in patients with CC. In 2013, two systematic reviews concluded that there was insufficient evidence to recommend NSAIDs for clinical management of CC outside of clinical trials. However, clinical trials of multi-component CC interventions have included NSAIDs as an intervention component, so an up-to-date assessment of the evidence for NSAIDs in the treatment of CC is warranted. Four databases (MEDLINE, EMBASE, CENTRAL and CINAHL) and three trial registers (clinicaltrials.gov, WHO ICTRP and ISRCTN) were searched on 16 December 2022. Randomized controlled trials (RCTs) comparing any NSAID (any dose or duration) with a control arm, in adult patients with CC, reporting measures of body weight, body composition, nutrition impact symptoms, inflammation, physical function or fatigue, were eligible for inclusion. Primary outcomes (determined with patient involvement) were survival, changes in muscle strength, body composition, body weight and quality of life. Included studies were assessed for risk of bias using the Revised Cochrane risk-of-bias tool for randomized trials. Five studies were included, which investigated Indomethacin (n = 1), Ibuprofen (n = 1) and Celecoxib (n = 3). Four studies were judged to be at high risk of bias for all outcomes, with one study raising concerns for most outcomes. Considerable clinical and methodological heterogeneity amongst the studies meant that meta-analysis was not appropriate. There was insufficient evidence to determine whether Indomethacin or Ibuprofen is effective or safe for use in patients with CC; RCTs with lower risk of bias are needed. Celecoxib studies indicated it was safe for use in this population at the doses tested (200-400 mg/day) but found contrasting results regarding efficacy, potentially reflecting heterogeneity amongst the studies. There is inadequate evidence to recommend any NSAID for CC. While current clinical trials for CC treatments are shifting towards multi-component interventions, further research to determine the efficacy and safety of NSAIDs alone is necessary if they are to be included in such multi-component interventions. Furthermore, the lack of data on patient-determined primary outcomes in this review highlights the need for patient involvement in clinical trials for CC.


Assuntos
Ibuprofeno , Neoplasias , Adulto , Humanos , Ibuprofeno/uso terapêutico , Celecoxib , Caquexia/etiologia , Caquexia/induzido quimicamente , Anti-Inflamatórios não Esteroides/uso terapêutico , Indometacina/uso terapêutico , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico
11.
Cell Stem Cell ; 27(1): 98-109.e11, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32386572

RESUMO

Altered neural stem/progenitor cell (NSPC) activity and neurodevelopmental defects are linked to intellectual disability. However, it remains unclear whether altered metabolism, a key regulator of NSPC activity, disrupts human neurogenesis and potentially contributes to cognitive defects. We investigated links between lipid metabolism and cognitive function in mice and human embryonic stem cells (hESCs) expressing mutant fatty acid synthase (FASN; R1819W), a metabolic regulator of rodent NSPC activity recently identified in humans with intellectual disability. Mice homozygous for the FASN R1812W variant have impaired adult hippocampal NSPC activity and cognitive defects because of lipid accumulation in NSPCs and subsequent lipogenic ER stress. Homozygous FASN R1819W hESC-derived NSPCs show reduced rates of proliferation in embryonic 2D cultures and 3D forebrain regionalized organoids, consistent with a developmental phenotype. These data from adult mouse models and in vitro models of human brain development suggest that altered lipid metabolism contributes to intellectual disability.


Assuntos
Metabolismo dos Lipídeos , Células-Tronco Neurais , Animais , Proliferação de Células , Ácido Graxo Sintases , Hipocampo , Transtornos da Memória , Camundongos , Neurogênese
13.
J Bone Joint Surg Am ; 100(2): 138-146, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29342064

RESUMO

BACKGROUND: Microfracture is commonly performed for cartilage repair but usually results in fibrocartilage. Microfracture augmented by autologous bone marrow concentrate (BMC) was previously shown to yield structurally superior cartilage repairs in an equine model compared with microfracture alone. The current study was performed to test the hypothesis that autologous BMC without concomitant microfracture improves cartilage repair compared with microfracture alone. METHODS: Autologous sternal bone marrow aspirate (BMA) was concentrated using a commercial system. Cells from BMC were evaluated for chondrogenic potential in vitro and in vivo. Bilateral full-thickness chondral defects (15-mm diameter) were created on the midlateral trochlear ridge in 8 horses. Paired defects were randomly assigned to treatment with BMC without concomitant microfracture, or to microfracture alone. The repairs were evaluated at 1 year by in vitro assessment, arthroscopy, morphological magnetic resonance imaging (MRI), quantitative T2-weighted and ultrashort echo time enhanced T2* (UTE-T2*) MRI mapping, and histological assessment. RESULTS: Culture-expanded but not freshly isolated cells from BMA and BMC underwent cartilage differentiation in vitro. In vivo, cartilage repairs in both groups were fibrous to fibrocartilaginous at 1 year of follow-up, with no differences observed between BMC and microfracture by arthroscopy, T2 and UTE-T2* MRI values, and histological assessment (p > 0.05). Morphological MRI showed subchondral bone changes not observed by arthroscopy and improved overall outcomes for the BMC repairs (p = 0.03). Differences in repair tissue UTE-T2* texture features were observed between the treatment groups (p < 0.05). CONCLUSIONS: When BMC was applied directly to critical-sized, full-thickness chondral defects in an equine model, the cartilage repair results were similar to those of microfracture. Our data suggest that, given the few mesenchymal stem cells in minimally manipulated BMC, other mechanisms such as paracrine, anti-inflammatory, or immunomodulatory effects may have been responsible for tissue regeneration in a previous study in which BMC was applied to microfractured repairs. While our conclusions are limited by small numbers, the better MRI outcomes for the BMC repairs may have been related to reduced surgical trauma to the subchondral bone. CLINICAL RELEVANCE: MRI provides important information on chondral defect subsurface repair organization and subchondral bone structure that is not well assessed by arthroscopy.


Assuntos
Transplante de Medula Óssea , Cartilagem Articular/lesões , Cartilagem Articular/cirurgia , Joelho de Quadrúpedes/lesões , Joelho de Quadrúpedes/cirurgia , Cicatrização/fisiologia , Animais , Artroscopia , Modelos Animais de Doenças , Cavalos , Imageamento por Ressonância Magnética , Distribuição Aleatória , Transplante Autólogo
14.
Clin Genitourin Cancer ; 16(6): 458-465.e2, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30115544

RESUMO

BACKGROUND: Metastatic germ cell tumors remain potentially curable when treated with salvage chemotherapy at first relapse. In the present phase I/II study, we sought to improve on the response rate and duration of the TIP (paclitaxel, ifosfamide, cisplatin) regimen by adding gemcitabine (Gem-TIP). MATERIALS AND METHODS: Twenty patients were recruited after failure of first-line cisplatin-containing chemotherapy. The primary objectives were to determine the maximum tolerated dose of gemcitabine when combined with TIP and to establish the dose intensity of the TIP drugs in this combination. The secondary objectives were the response rates, failure-free survival, and overall survival. RESULTS: The maximum tolerated dose of gemcitabine was 1200 mg/m2. The mean relative dose intensity was 95% (95% confidence interval [CI], 90.2%-99.2%) for gemcitabine, 96% (95% CI, 92.9%-98.7%) for paclitaxel, 92% (95% CI, 84.5%-98.8%) for ifosfamide, and 94% (95% CI, 89.3%-99.0%) for cisplatin. The overall complete response rate was 50%; another 30% of the patients achieved a partial response. The 1-year failure-free survival and overall survival rates were 68% (95% CI, 43%-84%) and 89.5% (95% CI, 64%-97%), respectively. CONCLUSION: Gemcitabine can be added to TIP chemotherapy at the full dose, with manageable toxicity and no detrimental effect on the dose intensity of the TIP drugs. The response rate and duration were improved compared with those reported from the Medical Research Council TIP trial; further evaluation is warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Desoxicitidina/análogos & derivados , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Terapia de Salvação/métodos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Neoplasias Embrionárias de Células Germinativas/mortalidade , Neoplasias Embrionárias de Células Germinativas/patologia , Terapia de Salvação/efeitos adversos , Taxa de Sobrevida , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Falha de Tratamento , Adulto Jovem , Gencitabina
15.
J Biomech ; 40(12): 2811-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17391677

RESUMO

Meniscal injuries place the knee at risk for early osteoarthritis (OA) because they disrupt their load-bearing capabilities. Partial resection is routinely performed to alleviate symptomatic meniscal tears. While the removal of meniscal tissue may not be the only factor associated with partial meniscectomy outcome, the amount removed certainly contributes to functional loss. It is unknown, however, whether there is a critical amount of meniscal tissue that can be removed without diminishing the structure's chondroprotective role. In order to examine the existence of such a threshold, it is necessary to accurately quantify meniscal volume both before and after partial meniscectomy to determine the amount of meniscal tissue removed. Therefore, our goal was to develop and validate an MR-based method for assessing meniscal volume. The specific aims were: (1) to evaluate the feasibility of the MR-based segmentation method; (2) to determine the method's reliability for repeated measurements; and (3) to validate its accuracy in situ. MR images were obtained on a 3T magnet, and each scan was segmented using a biplanar approach. The MR-based volumes for each specimen were compared to those measured by water displacement. The results indicate that the biplanar approach of measuring meniscal volumes is accurate and reliable. The calculated volumes of the menisci were within 5% of the true values, the coefficients of variation were 4%, and the intraclass correlation coefficients were greater than 0.96. These data demonstrate that this method could be used to measure the amount of meniscal tissue excised during partial meniscectomy to within 125.7 mm(3).


Assuntos
Imageamento Tridimensional , Traumatismos do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Meniscos Tibiais/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Idoso , Estudos de Viabilidade , Feminino , Humanos , Traumatismos do Joelho/complicações , Traumatismos do Joelho/cirurgia , Masculino , Meniscos Tibiais/cirurgia , Pessoa de Meia-Idade , Tamanho do Órgão , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/cirurgia , Radiografia , Fatores de Risco
17.
Health Technol Assess ; 19(102): 1-104, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26691209

RESUMO

BACKGROUND: Alcoholic hepatitis (AH) is a distinct presentation of alcoholic liver disease arising in patients who have been drinking to excess for prolonged periods, which is characterised by jaundice and liver failure. Severe disease is associated with high short-term mortality. Prednisolone and pentoxifylline (PTX) are recommended in guidelines for treatment of severe AH, but trials supporting their use have given heterogeneous results and controversy persists about their benefit. OBJECTIVES: The aim of the clinical effectiveness and cost-effectiveness of STeroids Or Pentoxifylline for Alcoholic Hepatitis trial was to resolve the clinical dilemma on the use of prednisolone or PTX. DESIGN: The trial was a randomised, double-blind, 2 × 2 factorial, multicentre design. SETTING: Sixty-five gastroenterology and hepatology inpatient units across the UK. PARTICIPANTS: Patients with a clinical diagnosis of AH who had a Maddrey's discriminant function value of ≥ 32 were randomised into four arms: A, placebo/placebo; B, placebo/prednisolone; C, PTX/placebo; and D, PTX/prednisolone. Of the 5234 patients screened for the trial, 1103 were randomised and after withdrawals, 1053 were available for primary end-point analysis. INTERVENTIONS: Those allocated to prednisolone were given 40 mg daily for 28 days and those allocated to PTX were given 400 mg three times per day for 28 days. OUTCOMES: The primary outcome measure was mortality at 28 days. Secondary outcome measures included mortality or liver transplant at 90 days and at 1 year. Rates of recidivism among survivors and the impact of recidivism on mortality were assessed. RESULTS: At 28 days, in arm A, 45 of 269 (16.7%) patients died; in arm B, 38 of 266 (14.3%) died; in arm C, 50 of 258 (19.4%) died; and in arm D, 35 of 260 (13.5%) died. For PTX, the odds ratio for 28-day mortality was 1.07 [95% confidence interval (CI) 0.77 to 1.40; p = 0.686)] and for prednisolone the odds ratio was 0.72 (95% CI 0.52 to 1.01; p = 0.056). In the logistic regression analysis, accounting for indices of disease severity and prognosis, the odds ratio for 28-day mortality in the prednisolone-treated group was 0.61 (95% CI 0.41 to 0.91; p = 0.015). At 90 days and 1 year there were no significant differences in mortality rates between the treatment groups. Serious infections occurred in 13% of patients treated with prednisolone compared with 7% of controls (p = 0.002). At the 90-day follow-up, 45% of patients reported being completely abstinent, 9% reported drinking within safety limits and 33% had an unknown level of alcohol consumption. At 1 year, 37% of patients reported being completely abstinent, 10% reported drinking within safety limits and 39% had an unknown level of alcohol consumption. Only 22% of patients had attended alcohol rehabilitation treatment at 90 days and 1 year. CONCLUSIONS: We conclude that prednisolone reduces the risk of mortality at 28 days, but this benefit is not sustained beyond 28 days. PTX had no impact on survival. Future research should focus on interventions to promote abstinence and on treatments that suppress the hepatic inflammation without increasing susceptibility to infection. TRIAL REGISTRATION: This trial is registered as EudraCT 2009-013897-42 and Current Controlled Trials ISRCTN88782125. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 102. See the NIHR Journals Library website for further project information. The NIHR Clinical Research Network provided research nurse support and the Imperial College Biomedical Research Centre also provided funding.


Assuntos
Glucocorticoides/uso terapêutico , Hepatite Alcoólica/tratamento farmacológico , Pentoxifilina/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Prednisolona/uso terapêutico , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Análise Custo-Benefício , Método Duplo-Cego , Feminino , Hepatite Alcoólica/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Análise de Sobrevida , Reino Unido , Adulto Jovem
18.
Trials ; 14: 262, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23958271

RESUMO

BACKGROUND: Alcoholic hepatitis is the most florid presentation of alcohol-related liver disease. In its severe form, defined by a Maddrey's discriminant function (DF) ≥32, the 28-day mortality rate is approximately 35%. A number of potential treatments have been subjected to clinical trials, of which two, corticosteroids and pentoxifylline, may have therapeutic benefit. The role of corticosteroids is controversial as trial results have been inconsistent, whereas the role of pentoxifylline requires confirmation as only one previous placebo-controlled trial has been published. METHODS/DESIGN: STOPAH is a multicentre, double-blind, factorial (2 × 2) trial in which patients are randomised to one of four groups:1. Group A: placebo / placebo2. Group B: placebo / prednisolone3. Group C: pentoxifylline / placebo4. Group D: pentoxifylline / prednisoloneThe trial aims to randomise 1,200 patients with severe alcoholic hepatitis, in order to provide sufficient power to determine whether either of the two interventions is effective. The primary endpoint of the study is mortality at 28 days, with secondary endpoints being mortality at 90 days and 1 year. DISCUSSION: STOPAH aims to be a definitive study to resolve controversy around the existing treatments for alcoholic hepatitis. Eligibility criteria are based on clinical parameters rather than liver biopsy, which are aligned with standard clinical practice in most hospitals. The use of a factorial design will allow two treatments to be evaluated in parallel, with efficient use of patient numbers to achieve high statistical power. TRIAL REGISTRATION: EudraCT reference number: 2009-013897-42 ISRCTN reference number: ISRCTN88782125.


Assuntos
Fígado Gorduroso Alcoólico/tratamento farmacológico , Glucocorticoides/uso terapêutico , Pentoxifilina/uso terapêutico , Prednisolona/uso terapêutico , Projetos de Pesquisa , Protocolos Clínicos , Método Duplo-Cego , Fígado Gorduroso Alcoólico/diagnóstico , Fígado Gorduroso Alcoólico/mortalidade , Humanos , Estimativa de Kaplan-Meier , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Reino Unido
19.
J Pediatr Genet ; 1(3): 199-203, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27625823

RESUMO

An adolescent female with Moebius syndrome developed paroxysmal hypertension, orthostatic hypotension and autonomic symptoms. Common causes of dysautonomia were excluded by the work-up, which supported a diagnosis of baroreflex failure. Neurological testing suggested dysfunction of the tenth cranial nerve as the etiology. This report suggests that baroreflex dysfunction should be considered in Moebius syndrome patients displaying autonomic symptoms.

20.
Arthritis Res Ther ; 14(3): 212, 2012 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-22682469

RESUMO

Osteoarthritis is a prevalent and disabling disease affecting an increasingly large swathe of the world population. While clinical osteoarthritis is a late-stage condition for which disease-modifying opportunities are limited, osteoarthritis typically develops over decades, offering a long window of time to potentially alter its course. The etiology of osteoarthritis is multifactorial, showing strong associations with highly modifiable risk factors of mechanical overload, obesity and joint injury. As such, characterization of pre-osteoarthritic disease states will be critical to support a paradigm shift from palliation of late disease towards prevention, through early diagnosis and early treatment of joint injury and degeneration to reduce osteoarthritis risk. Joint trauma accelerates development of osteoarthritis from a known point in time. Human joint injury cohorts therefore provide a unique opportunity for evaluation of pre-osteoarthritic conditions and potential interventions from the earliest stages of degeneration. This review focuses on recent advances in imaging and biochemical biomarkers suitable for characterization of the pre-osteoarthritic joint as well as implications for development of effective early treatment strategies.


Assuntos
Diagnóstico Precoce , Osteoartrite/diagnóstico , Humanos
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