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1.
Ophthalmology ; 130(4): 394-403, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36493903

RESUMO

PURPOSE: Observational studies suggest that myopic eyes carry a greater risk of primary open-angle glaucoma (POAG); however, the evidence for this association is inconsistent. This may be the result of confounding factors that arise from myopia that complicate clinical tests for glaucoma. This study used Mendelian randomization (MR) analysis to determine genetic causal associations among myopia, glaucoma, and glaucoma-related traits that overcome the effects of external confounders. DESIGN: Bidirectional genetic associations between myopia and refractive spherical equivalent (RSE), POAG, and POAG endophenotypes were investigated. PARTICIPANTS: Data from the largest publicly available genetic banks (n = 216,257-542,934) were analyzed. METHODS: Multiple MR models and multivariate genomic structural modeling to identify significant mediators for the relationship between myopia and POAG. MAIN OUTCOME MEASURES: Genetic causal associations between myopia and POAG and POAG endophenotypes. RESULTS: We found consistent bidirectional genetic associations between myopia and POAG and between myopia and intraocular pressure (IOP) using multiple MR models at Bonferroni-corrected levels of significance. Intraocular pressure showed the most significant mediation effect on RSE and POAG (Sobel test, 0.13; 95% confidence interval, 0.09-0.17; P = 1.37 × 10-8). CONCLUSIONS: A strong bidirectional genetic causal link exists between myopia and POAG that is mediated mainly by IOP. Our findings suggest that IOP-lowering treatment for glaucoma may be beneficial in myopic eyes, despite the challenges of establishing a clear clinical diagnosis. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Assuntos
Glaucoma de Ângulo Aberto , Miopia , Humanos , Pressão Intraocular , Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma de Ângulo Aberto/genética , Análise da Randomização Mendeliana , Tonometria Ocular , Miopia/diagnóstico
2.
J Neurooncol ; 163(1): 123-132, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37129738

RESUMO

OBJECTIVE: Persistent hydrocephalus following posterior fossa brain tumor (PFBT) resection is a common cause of morbidity in pediatric brain tumor patients, for which the optimal treatment is debated. The purpose of this study was to compare treatment outcomes between VPS and ETV in patients with persistent hydrocephalus following surgical resection of a PFBT. METHODS: A post-hoc analysis was performed of the Hydrocephalus Clinical Research Network (HCRN) prospective observational study evaluating VPS and ETV for pediatric patients. Children who experienced hydrocephalus secondary to PFBT from 2008 to 2021 were included. Primary outcomes were VPS/ETV treatment failure and time-to-failure (TTF). RESULTS: Among 241 patients, the VPS (183) and ETV (58) groups were similar in age, extent of tumor resection, and preoperative ETV Success Score. There was no difference in overall treatment failure between VPS and ETV (33.9% vs 31.0%, p = 0.751). However, mean TTF was shorter for ETV than VPS (0.45 years vs 1.30 years, p = 0.001). While major complication profiles were similar, compared to VPS, ETV patients had relatively higher incidence of minor CSF leak (10.3% vs. 1.1%, p = 0.003) and pseudomeningocele (12.1% vs 3.3%, p = 0.02). No ETV failures were identified beyond 3 years, while shunt failures occurred beyond 5 years. Shunt infections occurred in 5.5% of the VPS cohort. CONCLUSIONS: ETV and VPS offer similar overall success rates for PFBT-related postoperative hydrocephalus. ETV failure occurs earlier, while susceptibility to VPS failure persists beyond 5 years. Tumor histology and grade may be considered when selecting the optimal means of CSF diversion.


Assuntos
Hidrocefalia , Neoplasias Infratentoriais , Neuroendoscopia , Criança , Humanos , Ventriculostomia/efeitos adversos , Neuroendoscopia/efeitos adversos , Derivação Ventriculoperitoneal/efeitos adversos , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Hidrocefalia/epidemiologia , Resultado do Tratamento , Neoplasias Infratentoriais/complicações , Neoplasias Infratentoriais/cirurgia , Estudos Retrospectivos
3.
Pharmacology ; 107(3-4): 123-130, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34942623

RESUMO

INTRODUCTION: Sodium-glucose cotransporter 2 (SGLT2) inhibitors are increasingly utilized in the treatment of diabetes mellitus as well as therapeutic extra-glycemic effects. However, there are still concerns over complications such as amputation events, given the results from the Canagliflozin Cardiovascular Assessment Study (CANVAS) trial. Hence, we conducted a systematic review and meta-analysis of randomized-controlled trials to investigate the effect of SGLT2 inhibitors on amputation events. METHODS: Four electronic databases (PubMed, Embase, Cochrane, and SCOPUS) were searched on November 21, 2020, for articles published from January 1, 2000, up to November 21, 2020, for studies that examined the effect of SGLT2 inhibitors on amputation events. Random-effect pair-wise meta-analysis for hazard ratios and fixed-effect Peto odds ratio meta-analysis were utilized to summarize the studies. RESULTS: A total of 15 randomized-controlled trials were included with a combined cohort of 63,716 patients. We demonstrated that there was no significant difference in amputation events across different types of SGLT2 inhibitors, different baseline populations, and different duration of SGLT2 inhibitor use. DISCUSSION/CONCLUSIONS: In this meta-analysis, SGLT2 inhibitors were not associated with a significant difference in amputation events.


Assuntos
Diabetes Mellitus Tipo 2 , Amputação Cirúrgica , Glicemia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/cirurgia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sódio , Transportador 2 de Glucose-Sódio/uso terapêutico
4.
J Stroke Cerebrovasc Dis ; 31(1): 106159, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34689051

RESUMO

OBJECTIVES: Recent clinical trials have shown the potential of sodium glucose cotransporter (SGLT) 2 inhibitors to reduce the risk of atrial fibrillation but not stroke. We conducted a systematic review and meta-analysis to clarify if SGLT2 or combined SGLT1/2 inhibitors affect the risk of atrial fibrillation and stroke in patients regardless of diabetic status. MATERIALS AND METHODS: Four electronic databases were searched on 21st November 2020 for studies evaluating outcomes of stroke and atrial fibrillation with SGLT2 or combined SGLT1/2 inhibitors in both diabetic and non-diabetic patients. Both random and fixed effect, pair-wise meta-analysis models were used to summarize the results of the studies. RESULTS: A total of 13 placebo-controlled, randomized-controlled trials were included. Eight trials comprising 35,702 patients were included in the analysis of atrial fibrillation outcomes and eight trials comprising 47,910 patients were included in the analysis of stroke outcomes. Patients on SGLT inhibitors, particularly SGLT2 inhibitors, had lower odds of atrial fibrillation (Peto odds ratio [95% confidence interval] = 0.76 [0.63-0.92]) compared to placebo. This effect remained significant with a follow-up duration longer than 1 year, in studies utilizing dapagliflozin, patients with type 2 diabetes mellitus, and patients with cardiovascular disease. No difference was observed in the odds of atrial fibrillation in patients with baseline heart failure. No effect was seen on the risk of stroke in patients taking SGLT inhibitors. CONCLUSIONS: SGLT2 inhibitors significantly reduced the odds of atrial fibrillation in diabetic patients. However, SGLT inhibitors did not significantly affect the risk of stroke.


Assuntos
Fibrilação Atrial , Inibidores do Transportador 2 de Sódio-Glicose , Acidente Vascular Cerebral , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/prevenção & controle , Diabetes Mellitus/epidemiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Resultado do Tratamento
5.
Exp Cell Res ; 356(2): 173-181, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28219680

RESUMO

A sufficient supply molecular oxygen is essential for the maintenance of physiologic metabolism and bioenergetic homeostasis for most metazoans. For this reason, mechanisms have evolved for eukaryotic cells to adapt to conditions where oxygen demand exceeds supply (hypoxia). These mechanisms rely on the modification of pre-existing proteins, translational arrest and transcriptional changes. The hypoxia inducible factor (HIF; a master regulator of gene induction in response to hypoxia) is responsible for the majority of induced gene expression in hypoxia. However, much less is known about the mechanism(s) responsible for gene repression, an essential part of the adaptive transcriptional response. Hypoxia-induced gene repression leads to a reduction in energy demanding processes and the redirection of limited energetic resources to essential housekeeping functions. Recent developments have underscored the importance of transcriptional repressors in cellular adaptation to hypoxia. To date, at least ten distinct transcriptional repressors have been reported to demonstrate sensitivity to hypoxia. Central among these is the Repressor Element-1 Silencing Transcription factor (REST), which regulates over 200 genes. In this review, written to honor the memory and outstanding scientific legacy of Lorenz Poellinger, we provide an overview of our existing knowledge with respect to transcriptional repressors and their target genes in hypoxia.


Assuntos
Hipóxia Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Transcrição Gênica/fisiologia , Animais , Humanos , Hipóxia/genética , Oxigênio/metabolismo
6.
Am J Physiol Gastrointest Liver Physiol ; 311(6): G1076-G1090, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27789456

RESUMO

Fibrosis is a complication of chronic inflammatory disorders such as inflammatory bowel disease, a condition which has limited therapeutic options and often requires surgical intervention. Pharmacologic inhibition of oxygen-sensing prolyl hydroxylases, which confer oxygen sensitivity upon the hypoxia-inducible factor pathway, has recently been shown to have therapeutic potential in colitis, although the mechanisms involved remain unclear. Here, we investigated the impact of hydroxylase inhibition on inflammation-driven fibrosis in a murine colitis model. Mice exposed to dextran sodium sulfate, followed by a period of recovery, developed intestinal fibrosis characterized by alterations in the pattern of collagen deposition and infiltration of activated fibroblasts. Treatment with the hydroxylase inhibitor dimethyloxalylglycine ameliorated fibrosis. TGF-ß1 is a key regulator of fibrosis that acts through the activation of fibroblasts. Hydroxylase inhibition reduced TGF-ß1-induced expression of fibrotic markers in cultured fibroblasts, suggesting a direct role for hydroxylases in TGF-ß1 signaling. This was at least in part due to inhibition of noncanonical activation of extracellular signal-regulated kinase (ERK) signaling. In summary, pharmacologic hydroxylase inhibition ameliorates intestinal fibrosis through suppression of TGF-ß1-dependent ERK activation in fibroblasts. We hypothesize that in addition to previously reported immunosupressive effects, hydroxylase inhibitors independently suppress profibrotic pathways.


Assuntos
Colágeno/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Intestinos/patologia , Oxigenases de Função Mista/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Aminoácidos Dicarboxílicos/farmacologia , Animais , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose , Humanos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Oxigenases de Função Mista/antagonistas & inibidores , Transdução de Sinais
7.
Cell Mol Life Sci ; 72(12): 2431-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25697863

RESUMO

Cyclooxygenase 2 (COX2), a key regulatory enzyme of the prostaglandin/eicosanoid pathway, is an important target for anti-inflammatory therapy. It is highly induced by pro-inflammatory cytokines in a Nuclear factor kappa B (NFκB)-dependent manner. However, the mechanisms determining the amplitude and dynamics of this important pro-inflammatory event are poorly understood. Furthermore, there is significant difference between human and mouse COX2 expression in response to the inflammatory stimulus tumor necrosis factor alpha (TNFα). Here, we report the presence of a molecular logic AND gate composed of two NFκB response elements (NREs) which controls the expression of human COX2 in a switch-like manner. Combining quantitative kinetic modeling and thermostatistical analysis followed by experimental validation in iterative cycles, we show that the human COX2 expression machinery regulated by NFκB displays features of a logic AND gate. We propose that this provides a digital, noise-filtering mechanism for a tighter control of expression in response to TNFα, such that a threshold level of NFκB activation is required before the promoter becomes active and initiates transcription. This NFκB-regulated AND gate is absent in the mouse COX2 promoter, most likely contributing to its differential graded response in promoter activity and protein expression to TNFα. Our data suggest that the NFκB-regulated AND gate acts as a novel mechanism for controlling the expression of human COX2 to TNFα, and its absence in the mouse COX2 provides the foundation for further studies on understanding species-specific differential gene regulation.


Assuntos
Ciclo-Oxigenase 2/genética , Regulação da Expressão Gênica , Modelos Teóricos , NF-kappa B/metabolismo , Regiões Promotoras Genéticas/genética , Elementos de Resposta/genética , Animais , Western Blotting , Células Cultivadas , Imunoprecipitação da Cromatina , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Células HEK293 , Células HT29 , Humanos , Camundongos , NF-kappa B/genética , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
8.
Proc Natl Acad Sci U S A ; 110(46): 18490-5, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-24145445

RESUMO

Hypoxia is a prominent feature of chronically inflamed tissues. Oxygen-sensing hydroxylases control transcriptional adaptation to hypoxia through the regulation of hypoxia-inducible factor (HIF) and nuclear factor κB (NF-κB), both of which can regulate the inflammatory response. Furthermore, pharmacologic hydroxylase inhibitors reduce inflammation in multiple animal models. However, the underlying mechanism(s) linking hydroxylase activity to inflammatory signaling remains unclear. IL-1ß, a major proinflammatory cytokine that regulates NF-κB, is associated with multiple inflammatory pathologies. We demonstrate that a combination of prolyl hydroxylase 1 and factor inhibiting HIF hydroxylase isoforms regulates IL-1ß-induced NF-κB at the level of (or downstream of) the tumor necrosis factor receptor-associated factor 6 complex. Multiple proteins of the distal IL-1ß-signaling pathway are subject to hydroxylation and form complexes with either prolyl hydroxylase 1 or factor inhibiting HIF. Thus, we hypothesize that hydroxylases regulate IL-1ß signaling and subsequent inflammatory gene expression. Furthermore, hydroxylase inhibition represents a unique approach to the inhibition of IL-1ß-dependent inflammatory signaling.


Assuntos
Regulação da Expressão Gênica/fisiologia , Hipóxia/fisiopatologia , Inflamação/fisiopatologia , Oxigenases de Função Mista/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Análise de Variância , Western Blotting , Células HeLa , Humanos , Hidroxilação , Hipóxia/metabolismo , Imunoprecipitação , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Luciferases , Espectrometria de Massas , Prolil Hidroxilases/metabolismo , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo
9.
J Cell Sci ; 126(Pt 6): 1454-63, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23390316

RESUMO

Activation of the hypoxia-inducible factor (HIF) pathway is a critical step in the transcriptional response to hypoxia. Although many of the key proteins involved have been characterised, the dynamics of their interactions in generating this response remain unclear. In the present study, we have generated a comprehensive mathematical model of the HIF-1α pathway based on core validated components and dynamic experimental data, and confirm the previously described connections within the predicted network topology. Our model confirms previous work demonstrating that the steps leading to optimal HIF-1α transcriptional activity require sequential inhibition of both prolyl- and asparaginyl-hydroxylases. We predict from our model (and confirm experimentally) that there is residual activity of the asparaginyl-hydroxylase FIH (factor inhibiting HIF) at low oxygen tension. Furthermore, silencing FIH under conditions where prolyl-hydroxylases are inhibited results in increased HIF-1α transcriptional activity, but paradoxically decreases HIF-1α stability. Using a core module of the HIF network and mathematical proof supported by experimental data, we propose that asparaginyl hydroxylation confers a degree of resistance upon HIF-1α to proteosomal degradation. Thus, through in vitro experimental data and in silico predictions, we provide a comprehensive model of the dynamic regulation of HIF-1α transcriptional activity by hydroxylases and use its predictive and adaptive properties to explain counter-intuitive biological observations.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Oxigenases de Função Mista/metabolismo , Modelos Biológicos , Proteínas Repressoras/metabolismo , Biologia Computacional , Células HEK293 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/farmacologia , Oxigênio/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Estabilidade Proteica , Proteólise , RNA Interferente Pequeno/genética , Proteínas Repressoras/genética , Proteínas Repressoras/farmacologia , Transdução de Sinais , Ativação Transcricional/genética
10.
J Biol Chem ; 287(17): 14004-11, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22396550

RESUMO

Carbon dioxide (CO(2)) is increasingly being appreciated as an intracellular signaling molecule that affects inflammatory and immune responses. Elevated arterial CO(2) (hypercapnia) is encountered in a range of clinical conditions, including chronic obstructive pulmonary disease, and as a consequence of therapeutic ventilation in acute respiratory distress syndrome. In patients suffering from this syndrome, therapeutic hypoventilation strategy designed to reduce mechanical damage to the lungs is accompanied by systemic hypercapnia and associated acidosis, which are associated with improved patient outcome. However, the molecular mechanisms underlying the beneficial effects of hypercapnia and the relative contribution of elevated CO(2) or associated acidosis to this response remain poorly understood. Recently, a role for the non-canonical NF-κB pathway has been postulated to be important in signaling the cellular transcriptional response to CO(2). In this study, we demonstrate that in cells exposed to elevated CO(2), the NF-κB family member RelB was cleaved to a lower molecular weight form and translocated to the nucleus in both mouse embryonic fibroblasts and human pulmonary epithelial cells (A549). Furthermore, elevated nuclear RelB was observed in vivo and correlated with hypercapnia-induced protection against LPS-induced lung injury. Hypercapnia-induced RelB processing was sensitive to proteasomal inhibition by MG-132 but was independent of the activity of glycogen synthase kinase 3ß or MALT-1, both of which have been previously shown to mediate RelB processing. Taken together, these data demonstrate that RelB is a CO(2)-sensitive NF-κB family member that may contribute to the beneficial effects of hypercapnia in inflammatory diseases of the lung.


Assuntos
Dióxido de Carbono/química , Hipercapnia/metabolismo , Fator de Transcrição RelB/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Células Epiteliais/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Humanos , Camundongos , Modelos Biológicos , Interferência de RNA , Transdução de Sinais
11.
Cell Commun Signal ; 11(1): 42, 2013 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-23758895

RESUMO

Oxygen is a crucial molecule for cellular function. When oxygen demand exceeds supply, the oxygen sensing pathway centred on the hypoxia inducible factor (HIF) is switched on and promotes adaptation to hypoxia by up-regulating genes involved in angiogenesis, erythropoiesis and glycolysis. The regulation of HIF is tightly modulated through intricate regulatory mechanisms. Notably, its protein stability is controlled by the oxygen sensing prolyl hydroxylase domain (PHD) enzymes and its transcriptional activity is controlled by the asparaginyl hydroxylase FIH (factor inhibiting HIF-1).To probe the complexity of hypoxia-induced HIF signalling, efforts in mathematical modelling of the pathway have been underway for around a decade. In this paper, we review the existing mathematical models developed to describe and explain specific behaviours of the HIF pathway and how they have contributed new insights into our understanding of the network. Topics for modelling included the switch-like response to decreased oxygen gradient, the role of micro environmental factors, the regulation by FIH and the temporal dynamics of the HIF response. We will also discuss the technical aspects, extent and limitations of these models. Recently, HIF pathway has been implicated in other disease contexts such as hypoxic inflammation and cancer through crosstalking with pathways like NFκB and mTOR. We will examine how future mathematical modelling and simulation of interlinked networks can aid in understanding HIF behaviour in complex pathophysiological situations. Ultimately this would allow the identification of new pharmacological targets in different disease settings.

12.
Cell Mol Life Sci ; 69(8): 1319-29, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22068612

RESUMO

The oxygen-sensitive transcription factor hypoxia inducible factor (HIF) is a key regulator of gene expression during adaptation to hypoxia. Crucially, inflamed tissue often displays regions of prominent hypoxia. Recent studies have shown HIF signalling is intricately linked to that of the pro-inflammatory transcription factor nuclear factor kappa B (NFκB) during hypoxic inflammation. We describe the relative temporal contributions of each to hypoxia-induced inflammatory gene expression and investigate the level of crosstalk between the two pathways using a novel Gaussia princeps luciferase (Gluc) reporter system. Under the control of an active promoter, Gluc is expressed and secreted into the cell culture media, where it can be sampled and measured over time. Thus, Gluc constructs under the control of either HIF or NFκB were used to resolve their temporal transcriptional dynamics in response to hypoxia and to cytokine stimuli, respectively. We also investigated the interactions between HIF and NFκB activities using a construct containing the sequence from the promoter of the inflammatory gene cyclooxygenase 2 (COX-2), which includes functionally active binding sites for both HIF and NFκB. Finally, based on our experimental data, we constructed a mathematical model of the binding affinities of HIF and NFκB to their respective response elements to analyse transcriptional crosstalk. Taken together, these data reveal distinct temporal HIF and NFκB transcriptional activities in response to hypoxic inflammation. Furthermore, we demonstrate synergistic activity between these two transcription factors on the regulation of the COX-2 promoter, implicating a co-ordinated role for both HIF and NFκB in the expression of COX-2 in hypoxic inflammation.


Assuntos
Fator 1 Induzível por Hipóxia/imunologia , Hipóxia/imunologia , NF-kappa B/imunologia , Animais , Sequência de Bases , Linhagem Celular , Linhagem Celular Tumoral , Copépodes/enzimologia , Ciclo-Oxigenase 2/genética , Genes Reporter , Humanos , Hipóxia/genética , Fator 1 Induzível por Hipóxia/genética , Inflamação/genética , Inflamação/imunologia , Luciferases/genética , Modelos Biológicos , Dados de Sequência Molecular , NF-kappa B/genética , Regiões Promotoras Genéticas , Transcrição Gênica
13.
R Soc Open Sci ; 10(2): 220991, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36756060

RESUMO

Ageing research focuses on identifying lifespan modifiers and understanding and appropriately interpreting their effects. One of the most relevant quantities being studied is the shape of the survival curve that can reveal crucial information on the mechanism of action. Here, we introduce a bilogistic model to describe the shape of the lifespan curves of Caenorhabditis elegans populations. Using the corrected Akaike information criterion and the RMSE as goodness-of-fit tests, we show that the bilogistic model provides a better fit to the experimental data from nematode worms than other mathematical models and can identify and confirm biphasic lifespan data. Our parametric model offers a method to interpret replicate experiments data in terms of the shape parameters of the lifespan curve and enables robust statistical analysis of intra- and inter-group variance. We apply the model to novel lifespan data from C. elegans and Drosophila melanogaster and provide a rational statistical analysis of lifespan modifiers such as temperature and daf-16/FOXO mutation.

14.
Surv Ophthalmol ; 68(2): 257-264, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36427560

RESUMO

RATIONALE: Obstructive sleep apnoea (OSA) has been linked to various ocular disorders, including floppy eyelid syndrome (FES). Previous studies have hypothesised the underlying association between the 2 , but results are currently still inconclusive. OBJECTIVE: To investigate the association between OSA and FES. METHODS: Four databases (Pubmed, Embase, Scopus, and Cochrane Library) were searched from inception until 28 February 2022 for observational studies and randomized controlled trials assessing the association between OSA and FES. Two reviewers selected studies, extracted data, graded the risk of bias using the Newcastle-Ottawa scale and the quality of assessment using the Grading of Recommendations Assessment, Development, and Evaluation system. Random-effects models were used to metaanalyze the associations. RESULTS: Twelve studies were included in the systematic review, of which nine were suitable for metaanalysis, with a combined cohort of 1,109 patients. Risk of bias was low to moderate. The overall analysis showed a significant positive association between OSA and FES (OR = 1.89, 95% CI = 1.27-2.83, I 2 = 44%). Further analysis revealed that the more severe the OSA was, the higher the risk of developing FES. Patients with severe OSA had the nominally highest risk of developing FES (OR = 3.06, 95% CI = 1.62-5.78, I 2 = 0%), followed by moderate OSA (OR = 2.53, 95% CI = 1.29-4.97, I 2 = 0%), and patients with mild OSA had the lowest risk (OR = 1.76, 95% CI = 0.85-3.62, I 2 = 0%). CONCLUSION: Our metaanalysis reports a positive association between OSA and FES, with increasing severity of OSA correlating with a significantly higher risk of FES. More longitudinal studies with sufficient duration of follow-up are needed to better characterise the relationship between OSA and FES.


Assuntos
Doenças Palpebrais , Apneia Obstrutiva do Sono , Humanos , Síndrome , Doenças Palpebrais/complicações , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Pálpebras
15.
Eye (Lond) ; 37(15): 3065-3083, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36977937

RESUMO

INTRODUCTION: Obstructive sleep apnoea (OSA) has been thought to be associated with glaucoma, however there are many conflicting studies on this topic. With many new studies having been published since the previous meta-analysis, we believe it is important to clarify this association. Hence, in this study we meta-analyse the recent literature regarding the association between OSA and glaucoma. METHODS: Pubmed, Embase, Scopus and Cochrane Library were searched from inception till the 28th February 2022 for observational as well as cross-sectional studies examining the association between OSA and glaucoma. Two reviewers selected studies, extracted data, graded the quality of included non-randomized studies using the Newcastle-Ottawa scale. The overall quality of evidence was assessed using GRADE. Random-effects models were used to meta-analyse the maximally covariate- adjusted associations. RESULTS: 48 studies were included in our systematic review, with 46 suitable for meta-analysis. Total study population was 4,566,984 patients. OSA was associated with a higher risk of glaucoma (OR 3.66, 95% CI 1.70 to 7.90, I2 = 98%, p < 0.01). After adjustment for various important confounders including age, gender and patient comorbidities such as hyperlipidaemia, hypertension, cardiovascular diseases and diabetes, patients with OSA had up to 40% higher odds of glaucoma. Substantial heterogeneity was eliminated through subgroup and sensitivity analyses after consideration of glaucoma subtype, OSA severity and adjustment for confounders. CONCLUSIONS: In this meta-analysis, OSA was associated with higher risk of glaucoma, as well as more severe ocular findings characteristic of the glaucomatous disease process. We suggest more clinical studies looking into the effects of OSA treatment on the progression of glaucoma to help clinical decision making for patients.


Assuntos
Doenças Cardiovasculares , Glaucoma , Apneia Obstrutiva do Sono , Humanos , Estudos Transversais , Glaucoma/complicações , Glaucoma/epidemiologia , Coleta de Dados
16.
J Biol Chem ; 286(6): 4718-26, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21123177

RESUMO

Under conditions of hypoxia, most eukaryotic cells undergo a shift in metabolic strategy, which involves increased flux through the glycolytic pathway. Although this is critical for bioenergetic homeostasis, the underlying mechanisms have remained incompletely understood. Here, we report that the induction of hypoxia-induced glycolysis is retained in cells when gene transcription or protein synthesis are inhibited suggesting the involvement of additional post-translational mechanisms. Post-translational protein modification by the small ubiquitin related modifier-1 (SUMO-1) is induced in hypoxia and mass spectrometric analysis using yeast cells expressing tap-tagged Smt3 (the yeast homolog of mammalian SUMO) revealed hypoxia-dependent modification of a number of key glycolytic enzymes. Overexpression of SUMO-1 in mammalian cancer cells resulted in increased hypoxia-induced glycolysis and resistance to hypoxia-dependent ATP depletion. Supporting this, non-transformed cells also demonstrated increased glucose uptake upon SUMO-1 overexpression. Conversely, cells overexpressing the de-SUMOylating enzyme SENP-2 failed to demonstrate hypoxia-induced glycolysis. SUMO-1 overexpressing cells demonstrated focal clustering of glycolytic enzymes in response to hypoxia leading us to hypothesize a role for SUMOylation in promoting spatial re-organization of the glycolytic pathway. In summary, we hypothesize that SUMO modification of key metabolic enzymes plays an important role in shifting cellular metabolic strategies toward increased flux through the glycolytic pathway during periods of hypoxic stress.


Assuntos
Glicólise/fisiologia , Processamento de Proteína Pós-Traducional/fisiologia , Proteína SUMO-1/metabolismo , Trifosfato de Adenosina/genética , Trifosfato de Adenosina/metabolismo , Hipóxia Celular/fisiologia , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Células HeLa , Humanos , Proteína SUMO-1/genética , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo
18.
Phys Biol ; 9(4): 045007, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22871947

RESUMO

Gene expression is frequently regulated by multiple transcription factors (TFs). Thermostatistical methods allow for a quantitative description of interactions between TFs, RNA polymerase and DNA, and their impact on the transcription rates. We illustrate three different scales of the thermostatistical approach: the microscale of TF molecules, the mesoscale of promoter energy levels and the macroscale of transcriptionally active and inactive cells in a cell population. We demonstrate versatility of combinatorial transcriptional activation by exemplifying logic functions, such as AND and OR gates. We discuss a metric for cell-to-cell transcriptional activation variability known as Fermi entropy. Suitability of thermostatistical modeling is illustrated by describing the experimental data on transcriptional induction of NFκB and the c-Fos protein.


Assuntos
Simulação por Computador , Modelos Genéticos , Fatores de Transcrição/metabolismo , Ativação Transcricional , Algoritmos , Animais , Entropia , Lógica Fuzzy , Humanos , Modelos Estatísticos , NF-kappa B/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-fos/genética , Fatores de Transcrição/genética
19.
Ann Am Thorac Soc ; 19(3): 469-475, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34792438

RESUMO

Rationale: In 2020, lung cancer was the leading cause of cancer deaths and the most common cancer in men. Although obstructive sleep apnea (OSA) has been postulated to be carcinogenic, epidemiological studies are inconclusive. Objectives: To investigate the associations between OSA and the incidence and mortality of lung cancer. Methods: Four electronic databases (PubMed, Embase, Cochrane Library, and Scopus) were searched from inception until 6 June 2021 for randomized controlled trials and observational studies examining the association between sleep apnea and incident lung cancer. Two reviewers selected studies, extracted data, graded the risk of bias using the Newcastle-Ottawa scale and the quality of evidence using the Grading of Recommendations Assessment, Development, and Evaluation system. Random-effects models were used to meta-analyze the maximally covariate-adjusted associations. Results: Seven studies were included in our systematic review, among which four were suitable for meta-analysis, comprising a combined cohort of 4,885,518 patients. Risk of bias was low to moderate. OSA was associated with a higher incidence of lung cancer (hazard ratio, 1.25; 95% confidence interval, 1.02-1.53), with substantial heterogeneity (I2 = 97%). Heterogeneity was eliminated, with a stable pooled effect size, when including the three studies with at least 5 years of median follow-up (hazard ratio, 1.32; 95% confidence interval, 1.27-1.37; I2 = 0%). Conclusions: In this meta-analysis of 4,885,518 patients from four observational studies, patients with OSA had an approximately 30% higher risk of lung cancer compared with those without OSA. We suggest more clinical studies with longer follow-up as well as biological models of lung cancer be performed to further elucidate this relationship.


Assuntos
Neoplasias Pulmonares , Síndromes da Apneia do Sono , Apneia Obstrutiva do Sono , Estudos de Coortes , Humanos , Incidência , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/epidemiologia , Masculino , Estudos Observacionais como Assunto , Síndromes da Apneia do Sono/complicações , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia
20.
Clin Drug Investig ; 42(1): 1-16, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34797518

RESUMO

BACKGROUND AND OBJECTIVE: In recent trials, sodium-glucose cotransporter 2 (SGLT2) inhibitors proved effective as treatment for heart failure. However, the relative efficacy of sacubitril/valsartan against SGLT2 inhibitor in patients with heart failure remains unknown. Hence, we performed a network meta-analysis to compare the effects of sacubitril/valsartan against SGLT2 inhibitors on cardiovascular outcomes in patients with heart failure. METHODS: Four electronic databases (PubMed, Embase, Cochrane, SCOPUS) were searched for randomised-controlled trials (RCTs) published from 1st January 2000 to 25th September 2021. Two additional systematic reviews were conducted for RCTs of enalapril and valsartan to establish a common comparator arm. Frequentist network meta-analysis models were utilised to summarise the studies. RESULTS: Twenty-five RCTs were included, comprising a combined cohort of 47,275 patients. Network meta-analysis demonstrated that compared to SGLT2 inhibitors, sacubitril/valsartan achieved a larger hazard rate reduction in the composite of heart failure hospitalisation and cardiovascular death (hazard ratio [HR]: 0.86; 95% CI 0.75-0.98), cardiovascular death (HR: 0.78; 95% CI 0.65-0.94), and a larger mean change in systolic blood pressure at 8 or more months (weighted mean difference [WMD]: - 7.08 mmHg; 95% CI - 8.28 to - 5.89). There were no significant differences in treatment effects across heart failure hospitalisation, all-cause mortality, diastolic blood pressure at 12 weeks, and systolic blood pressure at 2-4 months. In patients with heart failure with reduced ejection fraction, sacubitril/valsartan achieved a 20% hazard rate reduction for cardiovascular death compared to SGLT2 inhibitors. CONCLUSIONS: In patients with heart failure, sacubitril/valsartan was demonstrated to be superior to SGLT2 inhibitors in the treatment effect for the composite of heart failure hospitalisation and cardiovascular death, cardiovascular death, and long-term blood pressure.


Assuntos
Compostos de Bifenilo , Insuficiência Cardíaca , Aminobutiratos , Combinação de Medicamentos , Glucose , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Metanálise em Rede , Sódio , Volume Sistólico , Tetrazóis/uso terapêutico , Valsartana
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