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OBJECTIVE: As endovascular interventions become safer and their use more prevalent for treating extracranial pseudoaneurysms, fewer pseudoaneurysms are treated with medical therapy alone. This study aimed to assess the indications for intervention and the safety of medical management. METHODS: A dual-center retrospective analysis was conducted on patients diagnosed with extracranial carotid and vertebral pseudoaneurysms between December 2006 and June 2023. RESULTS: Of 145 pseudoaneurysms, 121 (83%) received medical therapy, 22 (15%) were treated endovascularly, and 2 (1.4%) were treated with open surgery. In the medical group, there were 2 (1.9%) complications, one unrelated to the pseudoaneurysm. In the intervention group, there were 3 (16%) complications, with 1 patient requiring two retreatments and sacrifice of the vessel. Major trauma (OR 4.0, 95% CI 1.3-14; p = 0.02), use of digital subtraction angiography as the initial imaging modality (OR 9.8, 95% CI 2.5-42; p < 0.01), and a maximum lesion diameter > 6 mm (OR 5.3, 95% CI 1.4-25; p = 0.03) proved to be significant in the decision to intervene. At a median follow-up of 18.1 months, 94.7% of the lesions treated with intervention healed completely compared with 19% of aneurysms in the medical group. Among those medically managed that did not resolve, the median change in diameter was -0.4 mm (IQR -1.8 to 0.4 mm). Age ≤ 50 years and aneurysm maximum diameter ≤ 6 mm predicted healing at follow-up in the medical group with 92% specificity and 65% sensitivity (area under the curve 0.87). At follow-up, 98% of patients were functionally independent (modified Rankin Scale score ≤ 2). CONCLUSIONS: Medical management alone is safe for most extracranial pseudoaneurysms, resulting in significantly fewer complications than endovascular intervention. Maximum diameter ≤ 6 mm and age ≤ 50 years were significant predictors of pseudoaneurysm resolution with medical therapy alone. Lesions that do not heal do not cause further symptoms or require additional intervention.
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Thermophilic cyanobacteria thrive in extreme environments, making their thermoresistant enzymes valuable for industrial applications. Common habitats include hot springs, which act as evolutionary accelerators for speciation due to geographical isolation. The family Thermosynechococcaceae comprises thermophilic cyanobacteria known for their ability to thrive in high-temperature environments. These bacteria are notable for their photosynthetic capabilities, significantly contributing to primary production in extreme habitats. Members of Thermosynechococcaceae exhibit unique adaptations that allow them to perform photosynthesis efficiently at elevated temperatures, making them subjects of interest for studies on microbial ecology, evolution, and potential biotechnological applications. In this study, the genome of a thermophilic cyanobacterium, isolated from a hot spring near Okahandja in Namibia, was sequenced using a PacBio Sequel IIe long-read platform. Cultivations were performed at elevated temperatures of 40, 50, and 55°C, followed by proteome analyses based on the annotated genome. Phylogenetic investigations, informed by the 16S rRNA gene and aligned nucleotide identity (ANI), suggest that the novel cyanobacterium is a member of the family Thermosynechococcaceae. Furthermore, the new species was assigned to a separate branch, potentially representing a novel genus. Whole-genome alignments supported this finding, revealing few conserved regions and multiple genetic rearrangement events. Additionally, 129 proteins were identified as differentially expressed in a temperature-dependent manner. The results of this study broaden our understanding of cyanobacterial adaptation to extreme environments, providing a novel high-quality genome of Thermosynechococcaceae cyanobacterium sp. Okahandja and several promising candidate proteins for expression and characterization studies.
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Cianobactérias , Genoma Bacteriano , Fontes Termais , Filogenia , RNA Ribossômico 16S , Namíbia , Cianobactérias/genética , Cianobactérias/classificação , Cianobactérias/metabolismo , Fontes Termais/microbiologia , RNA Ribossômico 16S/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Temperatura Alta , Análise de Sequência de DNA , Proteoma/análise , DNA Bacteriano/genéticaRESUMO
BACKGROUND: Multiple factors have been proposed to affect the vessel ingrowth from the superficial temporal artery (STA) after Encephalo-Duro-Arterio-Synangiosis (EDAS). METHODS: This retrospective single-center analyses included patients with Moyamoya Disease (MMD) undergoing EDAS from January 1st, 2013, to December 31st, 2023. Evaluated variables included demographic characteristics, clinical presentation, technical details, modified Rankin Scale (mRS) scores, and radiographic outcomes. Univariate and multivariate analysis was performed to identify factors favoring the ingrowth of collaterals from the STA. RESULTS: Forty adult patients with MMD, most commonly females (77.5â¯%) with a median age of 48, underwent 56 EDAS. The most common initial presentations were ischemic events (75.0â¯%), followed by hemorrhagic events (27.5â¯%) and seizures (7.5â¯%). Digital angiography performed at a median of 13.7 months post-procedure revealed collateral growth from the STA in 78.6â¯% of cases, with a Matsushima grade A identified in 35.7â¯% of the revascularized hemispheres. Univariate analysis showed more collaterals in patients with a larger preoperative STA diameter (p=0.035), higher Suzuki grades (p=0.021) and longer angiographic follow-ups (p=0.048). Patients with occlusion of the internal carotid artery (ICA; p<0.01), middle cerebral artery (MCA; p<0.01), or anterior cerebral artery (ACA; p<0.01) also had more collateral ingrowth. Multivariate analysis revealed that ICA occlusion (OR=6.54; 95â¯% CI=1.03-41.48) and ACA occlusion (OR=6.52; 95â¯% CI=1.02-41.67) as predictors of collateral ingrowth from the STA. CONCLUSION: ICA and ACA occlusion were associated with success after EDAS. Longer follow-ups and larger STA demonstrated significant association on univariate analysis, but lost significance after adjusting for other procedural characteristics.
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BACKGROUND: Blood biomarkers predictive of the progression of idiopathic pulmonary fibrosis (IPF) would be of value for research and clinical practice. We used data from the IPF-PRO Registry to investigate whether the addition of "omics" data to risk prediction models based on demographic and clinical characteristics improved prediction of the progression of IPF. METHODS: The IPF-PRO Registry enrolled patients with IPF at 46 sites across the US. Patients were followed prospectively. Median follow-up was 27.2 months. Prediction models for disease progression included omics data (proteins and microRNAs [miRNAs]), demographic factors and clinical factors, all assessed at enrollment. Data on proteins and miRNAs were included in the models either as raw values or based on clusters in various combinations. Least absolute shrinkage and selection operator (Lasso) Cox regression was applied for time-to-event composite outcomes and logistic regression with L1 penalty was applied for binary outcomes assessed at 1 year. Model performance was assessed using Harrell's C-index (for time-to-event outcomes) or area under the curve (for binary outcomes). RESULTS: Data were analyzed from 231 patients. The models based on demographic and clinical factors, with or without omics data, were the top-performing models for prediction of all the time-to-event outcomes. Relative changes in average C-index after incorporating omics data into models based on demographic and clinical factors ranged from 1.7 to 3.2%. Of the blood biomarkers, surfactant protein-D, serine protease inhibitor A7 and matrix metalloproteinase-9 (MMP-9) were among the top predictors of the outcomes. For the binary outcomes, models based on demographics alone and models based on demographics plus omics data had similar performances. Of the blood biomarkers, CC motif chemokine 11, vascular cell adhesion protein-1, adiponectin, carcinoembryonic antigen and MMP-9 were the most important predictors of the binary outcomes. CONCLUSIONS: We identified circulating protein and miRNA biomarkers associated with the progression of IPF. However, the integration of omics data into prediction models that included demographic and clinical factors did not materially improve the performance of the models. TRIAL REGISTRATION: ClinicalTrials.gov; No: NCT01915511; registered August 5, 2013; URL: www. CLINICALTRIALS: gov .
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Biomarcadores , Fibrose Pulmonar Idiopática , Sistema de Registros , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/sangue , Fibrose Pulmonar Idiopática/genética , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Estudos Prospectivos , Biomarcadores/sangue , Valor Preditivo dos Testes , Progressão da Doença , Análise por Conglomerados , SeguimentosRESUMO
Drought is one of the most devastating causes of yield losses in crops like maize, and the anticipated increases in severity and duration of drought spells due to climate change pose an imminent threat to agricultural productivity. To understand the drought response, phenotypic and molecular studies are typically performed at a given time point after drought onset, representing a steady-state adaptation response. Because growth is a dynamic process, we monitored the drought response with high temporal resolution and examined cellular and transcriptomic changes after rehydration at 4 and 6 days after leaf four appearance. These data showed that division zone activity is a determinant for full organ growth recovery upon rehydration. Moreover, a prolonged maintenance of cell division by the ectopic expression of PLASTOCHRON1 extends the ability to resume growth after rehydration. The transcriptome analysis indicated that GROWTH-REGULATING FACTORS (GRFs) affect leaf growth by impacting cell division duration, which was confirmed by a prolonged recovery potential of the GRF1-overexpression line after rehydration. Finally, we used a multiplex genome editing approach to evaluate the most promising differentially expressed genes from the transcriptome study and as such narrowed down the gene space from 40 to seven genes for future functional characterization.
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BACKGROUND: AIDS-related Kaposi sarcoma (AIDS-KS) remains a leading cause of morbidity and mortality among people living with HIV in Africa. Mortality among people with AIDS-KS on antiretroviral therapy remains high compared with people on antiretroviral therapy who do not have AIDS-KS. SETTING: People living with HIV with Kaposi sarcoma (KS) who participated in 2 randomized trials (A5263/AMC066 [advanced stage] and A5264/AMC067 [mild-to-moderate stage]) conducted by AIDS Clinical Trials Group/AIDS Malignancy Consortium in low- and middle-income countries. METHODS: We estimated mortality rates over the trial period. Cox proportional hazards regressions were used to identify baseline characteristics associated with mortality and compared mortality rates between participants who had KS progression within 12 weeks of treatment initiation (early progression of KS [KS-PD]) and those who did not. RESULTS: Of the 329 and 189 eligible participants in A5263/AMC066 and A5264/AMC067, 71 (21.6%) and 24 (12.7%) died, respectively. In both trials, hypoalbuminemia was associated with increased hazards of death compared with normal albumin; A5263/AMC066: mild hypoalbuminemia (adjusted hazard ratio [aHR] = 3.01; 95% CI: 1.42 to 6.29), moderate hypoalbuminemia (aHR = 5.11; 95% CI: 2.54 to 10.29), and severe hypoalbuminemia (aHR = 14.58; 95% CI: 6.32 to 35.60), and A5264/AMC067: mild hypoalbuminemia (aHR = 5.66; 95% CI: 1.90 to 16.93) and moderate hypoalbuminemia (aHR = 7.02; 95% CI: 2.57 to 19.15). The rate of death was higher among participants who had early KS-PD than those without early KS-PD in A5263/AMC066 (HR = 5.09; 95% CI: 1.71 to 15.19) but not in A5264/AMC067 (HR = 1.74; 95% CI: 0.66 to 4.62). CONCLUSIONS: Albumin measurements may be used to identify individuals at higher risk of death after initiating KS treatment and for evaluation of interventions that can reduce AIDS-KS mortality.
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Infecções por HIV , Sarcoma de Kaposi , Humanos , Sarcoma de Kaposi/mortalidade , Sarcoma de Kaposi/epidemiologia , Sarcoma de Kaposi/complicações , Masculino , Feminino , Adulto , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Fatores de Risco , Pessoa de Meia-Idade , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Infecções Oportunistas Relacionadas com a AIDS/complicações , Fármacos Anti-HIV/uso terapêutico , Hipoalbuminemia/complicações , Hipoalbuminemia/epidemiologiaRESUMO
Combined oxidative phosphorylation deficiency (COXPD) is a rare multisystem disorder which is clinically and genetically heterogeneous. Genome sequencing identified biallelic MRPL49 variants in individuals from five unrelated families with presentations ranging from Perrault syndrome (primary ovarian insufficiency and sensorineural hearing loss) to severe childhood onset of leukodystrophy, learning disability, microcephaly and retinal dystrophy. Complexome profiling of fibroblasts from affected individuals revealed reduced levels of the small and, a more pronounced reduction of, the large mitochondrial ribosomal subunits. There was no evidence of altered mitoribosomal assembly. The reductions in levels of OXPHOS enzyme complexes I and IV are consistent with a form of COXPD associated with biallelic MRPL49 variants, expanding the understanding of how disruption of the mitochondrial ribosomal large subunit results in multi-system phenotypes.
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BACKGROUND: Children with Developmental Coordination Disorder (DCD) exhibit deficits in predictive motor control, balance, and aspects of cognitive control, which are important for safely negotiating obstacles while walking. As concurrent performance of cognitive and motor tasks (dual-tasking) may exacerbate these deficits, we examined motor and cognitive dual-tasking differences between children with DCD and their typically developing (TD) peers during obstacle negotiation. METHODS: 34 children aged 6-12 years (16 TD, 18 DCD) walked along a 12â¯m path, stepping over an obstacle (30â¯% or 50â¯% of leg length) at its mid-point. On dual-task trials, participants completed a simple or complex (cognitive) visual discrimination task presented via an augmented reality headset. Proportional dual-task costs (pDTCs) were measured on cognitive and gait outcomes over three phases: pre-obstacle, obstacle step-over, and post-obstacle. RESULTS: During the obstacle step-over phase, both groups increased their leading leg clearance when dual-tasking, while the DCD group had larger pDTC than TD for the high obstacle under simple stimulus conditions (viz simple-high combination). The complex cognitive task produced larger pDTCs than the simple one on leading leg clearance and post-obstacle gait variability. CONCLUSIONS: In general, both DCD and TD groups showed similar pDTCs under complex conditions, while the specific deficit in DCD under the simple-high combination suggests a (default) compensatory strategy during step-over when attention is diverted to a secondary task. Competing cognitive and motor demands during obstacle negotiation present a potential safety risk for children.
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Background: The role of type I and type III interferons (IFNs) in rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA) is still poorly understood. The objective of this study was to examine the hypothesis that IFN expression profiles in the peripheral blood differ between subsets of arthritic subjects. Multiple type I and type III IFNs were examined in patients with RA and JIA, as well as among subtypes of JIA. Methods: Treatment-naïve RA and JIA patients were enrolled. Droplet digital PCR was used to measure the expression of type I, II, and III interferons in blood and synovial fluid leukocytes. Dendritic cell subsets were isolated from synovial fluid to examine IFN expression in each subset. Additionally, synovial mononuclear cells and JIA-derived fibroblast-like synoviocytes were stimulated with TNF, IFNγ, and poly(I:C) to examine inducible IFN expression. Results: The predominant type I IFN gene expressed by blood leukocytes was IFNκ and was significantly lower in RA than JIA and controls. Oligoarticular and psoriatic JIA subgroups showed higher IFNκ expression compared to polyarticular JIA and RA. JIA synovial fluid leukocytes expressed abundant IFNγ and type III IFNs (IFNλ1, IFNλ3), with distinct dendritic cell subset contributions. JIA fibroblast-like synoviocytes produced IFNß, IFNλ1, and IFNλ2 mRNA upon poly(I:C) stimulation. Conclusion: This study revealed differences in IFN expression patterns in RA and JIA, with notable differences between JIA subtypes. The expression levels of IFNκ, IFNγ, IFNλ1 and IFNλ3 in JIA suggest specific roles in disease pathology, influenced by disease subtype and joint microenvironment. This study contributes to understanding IFN-mediated mechanisms in arthritis, potentially guiding targeted therapeutic strategies.
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Disorders of lipid metabolism such as obesity have become some of the most significant diseases of the twenty-first century. Despite these metabolic diseases affecting more than a third of the population in highly industrialized nations, the mechanisms underlying disease development remain poorly understood. Insect models, such as Drosophila melanogaster, offer a means of systematically examining conserved lipid metabolism and its pathology. Over the past several decades, Drosophila melanogaster has been used to greatly expand on our knowledge of metabolic disease, often taking advantage of the extensive genetic tools available to researchers. Additionally, Drosophila melanogaster has served and will continue to serve as a powerful tool for validating the results of genome-wide approaches to the study of diseases. This chapter explores the advancements of insect models in the study of lipid metabolism disorders as well as highlight opportunities for future areas of research.
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Due to their superior optical and electrical properties, gold nanowires are used ubiquitously across industries. Current techniques for fabricating such structures are often expensive, involving multiple steps, cleanroom operation, and limited ability for a user to controllably place a nanowire at a desired location. Here, we introduce the concept of triphasic electrodeposition, where metal salts act as antagonistic salts at the liquid|liquid interface, leading to their increased concentration at this phase boundary. We show that the electrodeposition of ultra-high aspect ratio gold nanowires may be achieved in a one-step, one-pot method by submerging a conductor in contact with two phases: an organic phase containing HAuCl4 and a quaternary ammonium salt, and an aqueous phase containing potassium chloride. Changing electrodeposition parameters in the triphasic system allows tunability of important features of the nanowire, such as size and thickness. Furthermore, this new method provides an impressive ability to choose the geometry and precise positioning of deposited nanowires simply by changing where a liquid|liquid interface contacts the electrode surface.
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Introduction: To evaluate the outcomes after stereotactic body radiotherapy (SBRT) for locally advanced primary liver cancer. Materials and methods: Patients with locally advanced liver cancer unsuitable for other loco-regional treatments were treated with SBRT with 50-60 Gy in 3-12 fractions in two consecutive prospective trials. Results: A total of 83 patients were included, of whom 14 were excluded, leaving 69 evaluable patients with 74 treated lesions. A total of 50 patients had hepatocellular carcinoma (HCC), and 11 patients had cholangiocarcinoma (CCC). Approximately 76% had a Child-Pugh (CP) score of A, while 54% had an albumin-bilirubin (ALBI) score of 1. With a median follow-up of 29 months, the median overall survival (OS) was 11 months, and the progression-free survival (PFS) was 18 months. The ALBI score was an important predictor of overall survival (HR 2.094, p = 0.001), which remained significant also in the multivariate analysis. Patients with an ALBI grade of ≥1 had an OS of 4 months versus 23 months in patients with an ALBI grade of 1 (p ≤ 0.001). The local control at 1 and 2 years was 91%. Thirteen patients developed grade ≥ 3 toxicities, of whom nine patients experienced liver toxicities. Patients with a higher ALBI score had a high risk for developing hepatic failure (OR 6.136, p = 0.006). Discussion: SBRT is a very effective treatment with low toxicity and should be considered as a local treatment option in patients with HCC and CCC. Patients with a higher ALBI grade are at risk for developing toxicities after SBRT and have a significantly lower survival rate.
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INTRODUCTION: Five of the neglected tropical diseases use a strategy of preventative chemotherapy distributed via mass drug administration (MDA) for all eligible people living in endemic areas. To be successful, high coverage must be sustained over multiple rounds. Therefore, it will be difficult to reach elimination as a public health problem using MDA if there remain clusters of people who have never been treated. The study aims to explore the reasons why people with high mobility report being never treated during MDA and to provide evidence to support the development of standardised questions for data collection using qualitative research tools. METHODS: We conducted an exploratory study using qualitative methods among displaced people, nomads/transhumants and economic migrants who self-reported that they had never been treated during MDA in the health districts of Tominian and Kalabancoro in Mali. Data were collected through in-depth individual interviews and focus group discussions. Nvivo V.14 software was used for data management and analysis. RESULTS: The main reasons reported for never treatment included: geographical mobility, lack of awareness/information, negative rumours, fear of side effects, conflict and insecurity and logistical difficulties faced in reaching these populations. Proposed solutions included involving communities in the MDA, increasing awareness and information campaigns, effectively managing side effects, and designing and implementing flexible and effective interventions. CONCLUSION: This study highlights that there are people with high mobility who may never have been treated during any round of MDA. The reasons for never treatment highlight the challenges faced when reaching particular groups during MDA activities/interventions. Suggested remedies will require programmes to implement more flexible and tailored interventions. Customised approaches based on the context are essential to guarantee fair access to preventive chemotherapy. Effective interventions must consider the supply and demand side in crafting interventions. This research adds to the evidence base to understand never treatment, particularly among highly mobile population groups and in schistosomiasis elimination programmes.
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Administração Massiva de Medicamentos , Pesquisa Qualitativa , Migrantes , Humanos , Mali , Feminino , Masculino , Adulto , Grupos Focais , Doenças Negligenciadas/tratamento farmacológico , Pessoa de Meia-Idade , Esquistossomose/tratamento farmacológico , Acessibilidade aos Serviços de Saúde , Conhecimentos, Atitudes e Prática em SaúdeRESUMO
Introduction: Live microfilariae (mf) and mf-derived extracellular vesicles (EVs) have been shown to modulate human antigen presenting cell (APC) function, most notably by suppressing the induction of IL-12 (and other pro-inflammatory cytokines) following activation with LPS and interferon-y. Methods: To explore further how EVs alter human APC function, we studied the effect of mf and EVs on human elutriated monocyte-derived dendritic cells (DC) following exposure to Mf, mf-derived excretory/secretory (E/S) products, E/S depleted of EVs through ultracentrifugation and purified EVs. After demonstrating that the measurable responses induced by live mf could be recapitulated by EVs and EV-containing E/S, we next performed RNAseq analysis of human DC following exposure to live mf, EVs, E/S, or EV-depleted E/S. Results: In our analyses of the data for the DC, using a false discovery rate (FDR)<0.05, EV-exposed DC had induced the expression of 212 differentially expressed genes (DEGs) when compared to unexposed DC and 157 when compared to E/S-depleted EVs. These genes were enriched in GO biological processes associated with neutrophil degranulation and 15 DEGs associated with KEGG Lysosome pathways. IPA analysis point to immune dysregulation. We next aimed to understand the intracellular processes altered by EVs and the effect these have on effector T cells. When SARS CoV-2 Membrane-specific CD4+ TCLs were assessed following EV conditioning of autologous DC and activation with the SARS CoV-2-Membrane peptide pool, we found conditioning reduced the frequency of SARS CoV-2 Membrane-specific CD3+ CD4+ CD154+ cells (p=.015). Similarly, EV-conditioning of SARS CoV-2 Membrane-specific CD3+ CD4+ cells induced fewer cell capable of producing IFN-γ (p=.045). Discussion: Taken together, our data suggest a modulatory role of EVs on APC function that likely leads to defects in T cell effector function.
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Brugia Malayi , Linfócitos T CD4-Positivos , Células Dendríticas , Vesículas Extracelulares , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Humanos , Brugia Malayi/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Antígenos de Helmintos/imunologia , Microfilárias/imunologia , Filariose/imunologia , Filariose/parasitologia , Citocinas/metabolismoRESUMO
Three-dimensional (3D) vegetation structure influences animal movements and, consequently, ecosystem functions. Animals disperse the seeds of 60%-90% of trees in tropical rainforests, which are among the most structurally complex ecosystems on Earth. Here, we investigated how 3D rainforest structure influences the movements of large, frugivorous birds and resulting spatial patterns of seed dispersal. We GPS-tracked white-thighed (Bycanistes albotibialis) and black-casqued hornbills (Ceratogymna atrata) in a study area surveyed by light detection and ranging (LiDAR) in southern Cameroon. We found that both species preferred areas of greater canopy height and white-thighed hornbill preferred areas of greater vertical complexity. In addition, 33% of the hornbills preferred areas close to canopy gaps, while 16.7% and 27.8% avoided large and small gaps, respectively. White-thighed hornbills avoided swamp habitats, while black-casqued increased their preference for swamps during the hottest temperatures. We mapped spatial probabilities of seed dispersal by hornbills, showing that 3D structural attributes shape this ecological process by influencing hornbill behaviour. These results provide evidence of a possible feedback loop between rainforest vegetation structure and seed dispersal by animals. Interactions between seed dispersers and vegetation structure described here are essential for understanding ecosystem functions in tropical rainforests and critical for predicting how rainforests respond to anthropogenic impacts.
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The mitoribosome synthesizes 13 protein subunits of the oxidative phosphorylation system encoded by the mitochondrial genome. The mitoribosome is composed of 12S rRNA, 16S rRNA and 82 mitoribosomal proteins encoded by nuclear genes. To date, variants in 12 genes encoding mitoribosomal proteins are associated with rare monogenic disorders, and frequently show combined oxidative phosphorylation deficiency. Here, we describe five unrelated individuals with biallelic variants in the DAP3 nuclear gene encoding mitoribosomal small subunit 29 (MRPS29), with variable clinical presentations ranging from Perrault syndrome (sensorineural hearing loss and ovarian insufficiency) to an early childhood neurometabolic phenotype. Assessment of respiratory chain function and proteomic profiling of fibroblasts from affected individuals demonstrated reduced MRPS29 protein levels, and consequently decreased levels of additional protein components of the mitoribosomal small subunit, associated with a combined complex I and IV deficiency. Lentiviral transduction of fibroblasts from affected individuals with wild-type DAP3 cDNA increased DAP3 mRNA expression, and partially rescued protein levels of MRPS7, MRPS9 and complex I and IV subunits, demonstrating the pathogenicity of the DAP3 variants. Protein modelling suggested that DAP3 disease-associated missense variants can impact ADP binding, and in vitro assays demonstrated DAP3 variants can consequently reduce both intrinsic and extrinsic apoptotic sensitivity, DAP3 thermal stability and DAP3 GTPase activity. Our study presents genetic and functional evidence that biallelic variants in DAP3 result in a multisystem disorder of combined oxidative phosphorylation deficiency with pleiotropic presentations, consistent with mitochondrial dysfunction.
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Natural-experiment designs that compare survivors of in-utero famine exposure to unaffected controls suggest that in-utero undernutrition predisposes to development of obesity. However, birth rates drop dramatically during famines. Selection bias could arise if factors that contribute to obesity also protect fertility and/or fetal survival under famine conditions. We investigated this hypothesis using genetic analysis of a famine-exposed birth cohort. We genotyped participants in the Dutch Hunger Winter Families Study (DHWFS, N=950; 45% male), of whom 51% were exposed to the 1944-1945 Dutch Famine during gestation and 49% were their unexposed same-sex siblings or "time controls" born before or after the famine in the same hospitals. We computed body-mass index (BMI) polygenic indices (PGIs) in DHWFS participants and compared BMI PGIs between famine-exposed and control groups. Participants with higher polygenic risk had higher BMIs (Pearson r=0.42, p<0.001). However, differences between BMI PGIs of famine-exposed participants and controls were small and not statistically different from zero across specifications (Cohen's d=0.10, p>0.092). Our findings did not indicate selection bias, supporting the validity of the natural-experiment design within DHWFS. In summary, our study outlines a novel approach to explore the presence of selection bias in famine and other natural experiment studies.
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Decreased presence or activity of human SLC26A4 at the plasma membrane is a common cause of hearing loss. SLC26A4 (Pendrin) is necessary for normal reabsorption of endolymph, the fluid bathing the inner ear. We identified the µ2 subunit of adaptor protein 2 (AP-2) complex required for clathrin-mediated endocytosis as a protein-partner of SLC26A4 involved in regulating its plasma membrane abundance. We showed that, in the endolymphatic sac, where fluid reabsorption occurs, SLC26A4 is localized along the apical microvilli of mitochondria-rich cells, in contact with the endolymph, and associated with clathrin-coated pits where µ2 and AP-2 are present. Based on SLC26A4 structure, the elements involved in SLC26A4-µ2 interaction were identified and validated experimentally, allowing modeling of this interaction at the atomic level. Pharmacological inhibition of clathrin-mediated endocytosis led to an increased plasma membrane abundance of hemagglutinin-tagged SLC26A4 virally or endogenously expressed in mitochondria-rich cells. These results indicate that the SLC26A4-µ2 interaction regulates SLC26A4 abundance at the apical surface of mitochondria-rich cells.
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Complexo 2 de Proteínas Adaptadoras , Membrana Celular , Endocitose , Saco Endolinfático , Transportadores de Sulfato , Animais , Humanos , Camundongos , Complexo 2 de Proteínas Adaptadoras/metabolismo , Membrana Celular/metabolismo , Clatrina/metabolismo , Saco Endolinfático/metabolismo , Mitocôndrias/metabolismo , Ligação Proteica , Transportadores de Sulfato/metabolismo , Transportadores de Sulfato/genéticaRESUMO
Effective treatment of pediatric acute leukemia is dependent on accurate genomic classification, typically derived from a combination of multiple time-consuming and costly techniques such as flow cytometry, fluorescence in situ hybridization (FISH), karyotype analysis, targeted PCR, and microarrays. We investigated the feasibility of a comprehensive single-assay classification approach using long-read sequencing, with real-time genome target enrichment, to classify chromosomal abnormalities and structural variants characteristic of acute leukemia. We performed whole genome sequencing on DNA from diagnostic peripheral blood or bone marrow for 54 pediatric acute leukemia cases with diverse genomic subtypes. We demonstrated the characterization of known, clinically relevant karyotype abnormalities and structural variants concordant with standard-of-care clinical testing. Subtype-defining genomic alterations were identified in all cases following a maximum of forty-eight hours of sequencing. In 18 cases, we performed real-time analysis - concurrent with sequencing - and identified the driving alteration in as little as fifteen minutes (for karyotype) or up to six hours (for complex structural variants). Whole genome nanopore sequencing with adaptive sampling has the potential to provide detailed genomic classification of acute leukemia specimens with reduced cost and turnaround time compared to the current standard of care.