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After chemotherapy, patients with non-seminomatous germ cell tumors (NSGCTs) with residual masses >1 cm on computed tomography (CT) undergo surgery. However, in approximately 50% of cases, these masses only consist of necrosis/fibrosis. We aimed to develop a radiomics score to predict the malignant character of residual masses to avoid surgical overtreatment. Patients with NSGCTs who underwent surgery for residual masses between September 2007 and July 2020 were retrospectively identified from a unicenter database. Residual masses were delineated on post-chemotherapy contrast-enhanced CT scans. Tumor textures were obtained using the free software LifeX. We constructed a radiomics score using a penalized logistic regression model in a training dataset, and evaluated its performance on a test dataset. We included 76 patients, with 149 residual masses; 97 masses were malignant (65%). In the training dataset (n = 99 residual masses), the best model (ELASTIC-NET) led to a radiomics score based on eight texture features. In the test dataset, the area under the curve (AUC), sensibility, and specificity of this model were respectively estimated at 0.82 (95%CI, 0.69-0.95), 90.6% (75.0-98.0), and 61.1% (35.7-82.7). Our radiomics score may help in the prediction of the malignant nature of residual post-chemotherapy masses in NSGCTs before surgery, and thus limit overtreatment. However, these results are insufficient to simply select patients for surgery.
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Haemophilus influenzae is an obligate human commensal/pathogen. This haem auxotroph must acquire haem from its host to sustain aerobic growth. Haem-haemopexin complexes are one of the potential sources of haem for this microorganism. Haemopexin is a glycoprotein that binds haem with high affinity (subpicomolar Kd) and involved in haem recycling. HxuA, a cell surface protein, is the key to haem acquisition from haemopexin. In this study, we reconstituted a functional Hxu system from H. influenzae in Escherichia coli K-12 that mediated active haem transport across the outer membrane from haem-haemopexin, in the presence of the inner membrane energy-transducing TonB-ExbB-ExbD complex from H. influenzae. A secreted variant of HxuA, HxuA(dm), was produced in E. coli. HxuA(dm) functionally complemented an hxuA mutant of H. influenzae for haem-haemopexin acquisition. HxuA(dm) interacted with haemopexin and haem-haemopexin, with which it formed high-affinity, stoichiometric complexes. Following the interaction between haem-haemopexin and HxuA(dm), haem was no longer bound to its initial high-affinity site and became accessible to its cognate haem receptor, HxuC. HxuA(dm) and the HxuA(dm)-haemopexin complex do not appear to bind haem at detectable levels (affinities below 10(6) M(-1)). HxuA thus appears to 'release' haem from haem-haemopexin complexes and to prevent haem sequestering by haemopexin.
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Proteínas de Bactérias/metabolismo , Haemophilus influenzae/metabolismo , Heme/metabolismo , Hemopexina/metabolismo , Proteínas de Bactérias/genética , Calorimetria , Eletroforese , Escherichia coli K12 , ImmunoblottingRESUMO
Events of viral contaminations occurring during the production of biopharmaceuticals have been publicly reported by the biopharmaceutical industry. Upstream raw materials were often identified as the potential source of contamination. Viral contamination risk can be mitigated by inactivating or eliminating potential viruses of cell culture media and feed solutions. Different methods can be used alone or in combination on raw materials, cell culture media, or feed solutions such as viral inactivation technologies consisting mainly of high temperature short time, ultraviolet irradiation, and gamma radiation technologies or such as viral removal technology for instance nanofiltration. The aim of this review is to present the principle, the advantages, and the challenges of high temperature short time (HTST) technology. Here, we reviewed effectiveness of HTST treatment and its impact on media (filterability of media, degradation of components), on process performance (cell growth, cell metabolism, productivity), and product quality based on knowledge shared in the literature.
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Meios de Cultura , Contaminação de Medicamentos/prevenção & controle , Temperatura Alta , Pasteurização/métodos , Vírus/patogenicidade , Animais , Células CHO , Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/normas , Cricetinae , Cricetulus , Meios de Cultura/química , Meios de Cultura/normas , Indústria Farmacêutica , Células HEK293 , Humanos , Inativação de Vírus/efeitos da radiaçãoRESUMO
A (GGGGCC)n repeat expansion in C9orf72 gene is the major cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The relations between the repeats size and the age at disease onset (AO) or the clinical phenotype (FTD vs. ALS) were investigated in 125 FTD, ALS, and presymptomatic carriers. Positive correlations were found between repeats number and the AO (p < 10e-4) but our results suggested that the association was mainly driven by age at collection (p < 10e-4). A weaker association was observed with clinical presentation (p = 0.02), which became nonsignificant after adjustment for the age at collection in each group. Importantly, repeats number variably expanded or contracted over time in carriers with multiple blood samples, as well as through generations in parent-offspring pairs, conversely to what occurs in several expansion diseases with anticipation at the molecular level. Finally, this study establishes that measure of repeats number in lymphocytes is not a reliable biomarker predictive of the AO or disease outcome in C9orf72 long expansion carriers.
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Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/sangue , Proteína C9orf72/genética , Expansão das Repetições de DNA/genética , Demência Frontotemporal/genética , Heterozigoto , Adulto , Fatores Etários , Idade de Início , Idoso , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/epidemiologia , Coleta de Amostras Sanguíneas , Feminino , Demência Frontotemporal/sangue , Demência Frontotemporal/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , FenótipoRESUMO
Frontotemporal dementia (FTD) is a fatal neurodegenerative disease characterized by behavioral and language disorders. The main genetic cause of FTD is an intronic hexanucleotide repeat expansion (G4C2)n in the C9ORF72 gene. A loss of function of the C9ORF72 protein associated with the allele-specific reduction of C9ORF72 expression is postulated to contribute to the disease pathogenesis. To better understand the contribution of the loss of function to the disease mechanism, we need to determine precisely the level of reduction in C9ORF72 long and short isoforms in brain tissue from patients with C9ORF72 mutations. In this study, we developed a sensitive and robust mass spectrometry (MS) method for quantifying C9ORF72 isoform levels in human brain tissue without requiring antibody or affinity reagent. An optimized workflow based on surfactant-aided protein extraction and pellet digestion was established for optimal recovery of the two isoforms in brain samples. Signature peptides, common or specific to the isoforms, were targeted in brain extracts by multiplex MS through the parallel reaction monitoring mode on a Quadrupole-Orbitrap high resolution mass spectrometer. The assay was successfully validated and subsequently applied to frontal cortex brain samples from a cohort of FTD patients with C9ORF72 mutations and neurologically normal controls without mutations. We showed that the C9ORF72 short isoform in the frontal cortices is below detection threshold in all tested individuals and the C9ORF72 long isoform is significantly decreased in C9ORF72 mutation carriers.
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Multiciliated ependymal cells line all brain cavities. The beating of their motile cilia contributes to the flow of cerebrospinal fluid, which is required for brain homoeostasis and functions. Motile cilia, nucleated from centrioles, persist once formed and withstand the forces produced by the external fluid flow and by their own cilia beating. Here, we show that a dense actin network around the centrioles is induced by cilia beating, as shown by the disorganisation of the actin network upon impairment of cilia motility. Moreover, disruption of the actin network, or specifically of the apical actin network, causes motile cilia and their centrioles to detach from the apical surface of ependymal cell. In conclusion, cilia beating controls the apical actin network around centrioles; the mechanical resistance of this actin network contributes, in turn, to centriole stability.
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Actinas/fisiologia , Centríolos/fisiologia , Cílios/fisiologia , Epêndima/fisiologia , Actinas/química , Animais , Fenômenos Biomecânicos , Proteínas do Citoesqueleto , Epêndima/crescimento & desenvolvimento , Epêndima/ultraestrutura , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteínas dos Microfilamentos , Modelos Neurológicos , Mapas de Interação de Proteínas , Proteínas/genética , Proteínas/metabolismoRESUMO
Importance: Presymptomatic carriers of chromosome 9 open reading frame 72 (C9orf72) mutation, the most frequent genetic cause of frontotemporal lobar degeneration and amyotrophic lateral sclerosis, represent the optimal target population for the development of disease-modifying drugs. Preclinical biomarkers are needed to monitor the effect of therapeutic interventions in this population. Objectives: To assess the occurrence of cognitive, structural, and microstructural changes in presymptomatic C9orf72 carriers. Design, Setting, and Participants: The PREV-DEMALS study is a prospective, multicenter, observational study of first-degree relatives of individuals carrying the C9orf72 mutation. Eighty-four participants entered the study between October 2015 and April 2017; 80 (95%) were included in cross-sectional analyses of baseline data. All participants underwent neuropsychological testing and magnetic resonance imaging; 63 (79%) underwent diffusion tensor magnetic resonance imaging. Gray matter volumes and diffusion tensor imaging metrics were calculated within regions of interest. Anatomical and microstructural differences between individuals who carried the C9orf72 mutation (C9+) and those who did not carry the C9orf72 mutation (C9-) were assessed using linear mixed-effects models. Data were analyzed from October 2015 to April 2017. Main Outcomes and Measures: Differences in neuropsychological scores, gray matter volume, and white matter integrity between C9+ and C9- individuals. Results: Of the 80 included participants, there were 41 C9+ individuals (24 [59%] female; mean [SD] age, 39.8 [11.1] years) and 39 C9- individuals (24 [62%] female; mean [SD] age, 45.2 [13.9] years). Compared with C9- individuals, C9+ individuals had lower mean (SD) praxis scores (163.4 [6.1] vs 165.3 [5.9]; P = .01) and intransitive gesture scores (34.9 [1.6] vs 35.7 [1.5]; P = .004), atrophy in 8 cortical regions of interest and in the right thalamus, and white matter alterations in 8 tracts. When restricting the analyses to participants younger than 40 years, compared with C9- individuals, C9+ individuals had lower praxis scores and intransitive gesture scores, atrophy in 4 cortical regions of interest and in the right thalamus, and white matter alterations in 2 tracts. Conclusions and Relevance: Cognitive, structural, and microstructural alterations are detectable in young C9+ individuals. Early and subtle praxis alterations, underpinned by focal atrophy of the left supramarginal gyrus, may represent an early and nonevolving phenotype related to neurodevelopmental effects of C9orf72 mutation. White matter alterations reflect the future phenotype of frontotemporal lobar degeneration/amyotrophic lateral sclerosis, while atrophy appears more diffuse. Our results contribute to a better understanding of the preclinical phase of C9orf72 disease and of the respective contribution of magnetic resonance biomarkers. Trial Registration: clinicaltrials.gov Identifier: NCT02590276.
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Doenças Assintomáticas , Encéfalo/diagnóstico por imagem , Proteína C9orf72/genética , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/genética , Mutação/genética , Adulto , Idoso , Transtornos Cognitivos/etiologia , Estudos de Coortes , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Substância Branca/patologia , Adulto JovemRESUMO
OBJECTIVE: To quantify the effect of genetic factors and generations influencing the age at onset (AAO) in families with frontotemporal lobar dementia (FTD) due to C9ORF72 hexanucleotide repeat expansions and GRN mutations. METHODS: We studied 504 affected individuals from 133 families with C9ORF72 repeat expansions and 90 FTD families with mutations in GRN, 2 major genes responsible for FTD and/or amyotrophic lateral sclerosis. Intrafamilial correlations of AAO were analyzed, and variance component methods were used for heritability estimates. Generational effects on hazard rates for AAO were assessed using mixed-effects Cox proportional hazard models. RESULTS: A generational effect influencing AAO was detected in both C9ORF72 and GRN families. Nevertheless, the estimated proportion of AAO variance explained by genetic factors was high in FTD caused by C9ORF72 repeat expansions (44%; p = 1.10e-4), 62% when the AAO of dementia was specifically taken into account (p = 8.10e-5), and to a lesser degree in GRN families (26%; p = 0.17). Intrafamilial correlation analyses revealed a significant level of correlations in C9ORF72 families according to the degree of kinship. A pattern of intrafamilial correlations also suggested potential X-linked modifiers acting on AAO. Nonsignificant correlation values were observed in GRN families. CONCLUSIONS: Our results provide original evidence that genetic modifiers strongly influence the AAO in C9ORF72 carriers, while their effects seem to be weaker in GRN families. This constitutes a rational to search for genetic biomarkers, which could help to improve genetic counseling, patient care, and monitoring of therapeutic trials.