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OBJECTIVE: Information on bladder cancer (BC) according to the risk scoring for recurrence or progression in a general population is scarce despite its clinical relevance. The objective was to describe the characteristics of incident BC in a general population, with a focus on the initial management of high-risk non-muscle invasive BC (HR-NMIBC). MATERIALS: BC incident in 2011-2012 recorded in a population-based cancer registry were studied. Data was extracted from medical files. NMIBC were classified according to potential risk for recurrence/progression. Individual and tumor characteristics of incident BC were described. Incidence, initial management and survival (12/31/2021) of HR-NMIBC were assessed. RESULTS: Among 538 BC cases, 380 were NMIBC [119 low (22.1%), 163 intermediate (30.3%), 98 high (18.2%) risk] and 147 (27.3%) were MIBC. HR-NMIBC diagnostic and therapeutic management [imaging, re-TUR, multidisciplinary team meetings (MDT) assessment, specific treatment] revealed discrepancies with guidelines recommendations. Seventy-two out of 98 cases were assessed in an MDT with a median time from diagnosis of 18days [first quartile: 12-third quartile: 32]. Globally, treatment agreed with MDT decisions. Intravesical instillation was the most common treatment (n=56) but 27 HR-NMIBC did not receive specific treatment after TUR. Five and 10years overall survival was 52% [42-63] and 41% [31-51], respectively. Five years net survival was 63% [47-75]. CONCLUSIONS: Despite National cancer plans aiming to improve care giving and despite the severity of HR-NMIBC, guideline-recommended patterns of care were underused in this region. This may deserve attention to identify obstacles to guideline adoption to try to improve BC patient care and survival.
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Bladder cancer (BC) is a common malignancy in Europe and North America. Among BCs, muscle-invasive BCs (MIBCs) are distinguished, as they require aggressive treatment due to their spreading potential and poor prognosis. Despite its clinical relevance, little information on MIBC in a general population setting is available. This study aims to report practice patterns and survival outcomes for MIBC patients in a general population setting. MIBCs among BC incidence in 2011 and 2012 recorded in a French population-based cancer registry (810 000 inhabitants) were included in the study. Data were extracted from the medical files. Individual, tumour-related characteristics and initial management including diagnostic tools, multidisciplinary team meeting (MDT) assessment, and treatment delivered were described. Cystectomy, chemoradiation, radiotherapy, and chemotherapy were considered as specific treatments. Matching between MDT decision and the treatment provided was detailed. Management practices were discussed according to the guideline's recommendations. Overall survival (using the Kaplan-Meier method) and net survival (using the Pohar-Perme estimator) were calculated. Among 538 incident BC cases, 147 (27.3%) were MIBCs. Diagnostic practices displayed a relevant locoregional assessment of BC. Almost all cases (n = 136, 92.5%) were assessed during an uro-oncological MDT with a median time from diagnosis of 18 days (first quartile:12-third quartile:32). Discrepancies appeared between MDT decisions and treatments delivered: 71 out of 86 subjects received the recommended cystectomy or chemoradiation (with or without neoadjuvant chemotherapy); 6 out of 11 had the recommended radio- or chemotherapy; and 9 patients did not undergo any specific treatment despite the MDT decision. Cystectomy was the most common treatment performed; the time to surgery appeared consistent with the guideline's recommendations. Forty people only received supportive care. Still, the 5-year overall and net survival was poor, with 19% (13-26) and 22% (14-31), respectively. The 5-year net survival was 35% (23-48) for people who underwent curative-intent treatments. MIBC management remains challenging even for cases assessed during an MDT. Many people did not undergo any specific treatment. Prognosis was poor even when curative-intent therapies were delivered. Efforts to reduce exposure to risk factors such as tobacco smoking and occupational exposures must be maintained.
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Cistectomía , Pautas de la Práctica en Medicina , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/terapia , Neoplasias de la Vejiga Urinaria/mortalidad , Masculino , Femenino , Anciano , Persona de Mediana Edad , Pautas de la Práctica en Medicina/estadística & datos numéricos , Anciano de 80 o más Años , Francia/epidemiología , Invasividad Neoplásica , Sistema de RegistrosRESUMEN
BACKGROUND AND OBJECTIVE: Prostate multiparametric magnetic resonance imaging (MRI) shows high sensitivity for International Society of Urological Pathology grade group (GG) ≥2 cancers. Many artificial intelligence algorithms have shown promising results in diagnosing clinically significant prostate cancer on MRI. To assess a region-of-interest-based machine-learning algorithm aimed at characterising GG ≥2 prostate cancer on multiparametric MRI. METHODS: The lesions targeted at biopsy in the MRI-FIRST dataset were retrospectively delineated and assessed using a previously developed algorithm. The Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2) score assigned prospectively before biopsy and the algorithm score calculated retrospectively in the regions of interest were compared for diagnosing GG ≥2 cancer, using the areas under the curve (AUCs), and sensitivities and specificities calculated with predefined thresholds (PIRADSv2 scores ≥3 and ≥4; algorithm scores yielding 90% sensitivity in the training database). Ten predefined biopsy strategies were assessed retrospectively. KEY FINDINGS AND LIMITATIONS: After excluding 19 patients, we analysed 232 patients imaged on 16 different scanners; 85 had GG ≥2 cancer at biopsy. At patient level, AUCs of the algorithm and PI-RADSv2 were 77% (95% confidence interval [CI]: 70-82) and 80% (CI: 74-85; p = 0.36), respectively. The algorithm's sensitivity and specificity were 86% (CI: 76-93) and 65% (CI: 54-73), respectively. PI-RADSv2 sensitivities and specificities were 95% (CI: 89-100) and 38% (CI: 26-47), and 89% (CI: 79-96) and 47% (CI: 35-57) for thresholds of ≥3 and ≥4, respectively. Using the PI-RADSv2 score to trigger a biopsy would have avoided 26-34% of biopsies while missing 5-11% of GG ≥2 cancers. Combining prostate-specific antigen density, the PI-RADSv2 and algorithm's scores would have avoided 44-47% of biopsies while missing 6-9% of GG ≥2 cancers. Limitations include the retrospective nature of the study and a lack of PI-RADS version 2.1 assessment. CONCLUSIONS AND CLINICAL IMPLICATIONS: The algorithm provided robust results in the multicentre multiscanner MRI-FIRST database and could help select patients for biopsy. PATIENT SUMMARY: An artificial intelligence-based algorithm aimed at diagnosing aggressive cancers on prostate magnetic resonance imaging showed results similar to expert human assessment in a prospectively acquired multicentre test database.
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The expression of glypicans in different hair follicle (HF) compartments is still poorly understood. Heparan sulfate proteoglycans (HSPGs) distribution in HF is classically investigated by conventional histology, biochemical analysis, and immunohistochemistry. Our previous study proposed a novel approach to assess hair histology and glypican-1 (GPC1) distribution changes in the HF at different phases of the hair growth cycle using infrared spectral imaging (IRSI). We show in the present manuscript for the first time complementary data on the distribution of glypican-4 (GPC4) and glypican-6 (GPC6) in HF at different phases of the hair growth cycle using IR imaging. Findings were supported by Western blot assays focusing on the GPC4 and GPC6 expression in HFs. Like all proteoglycan features, the glypicans are characterized by a core protein to which sulfated and/or unsulfated glycosaminoglycan (GAG) chains are covalently linked. Our study demonstrates the capacity of IRSI to identify the different HF tissue structures and to highlight protein, proteoglycan (PG), GAG, and sulfated GAG distribution in these structures. The comparison between anagen, catagen, and telogen phases shows the qualitative and/or quantitative evolution of GAGs, as supported by Western blot. Thus, in one analysis, IRSI can simultaneously reveal the location of proteins, PGs, GAGs and sulfated GAGs in HFs in a chemical and label-free manner. From a dermatological point of view, IRSI may constitute a promising technique to study alopecia.
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Glipicanos , Proteoglicanos de Heparán Sulfato , Glipicanos/metabolismo , Proteoglicanos de Heparán Sulfato/metabolismo , Cabello/metabolismo , Folículo Piloso/metabolismoRESUMEN
The classical analyses of indirect communication between different cell types necessitate the use of conditioned media. Moreover, the production of conditioned media remains time-consuming and far from physiological and pathological conditions. Although a few models of co-culture are commercially available, they remain restricted to specific assays and are mostly for two types of cells. Here, 3D-printed inserts are used that are compatible with numerous functional assays. The insert allows the separation of one well of a 6-well plate into four compartments. A wide range of combinations can be set. Moreover, windows are designed in each wall of the compartments so that potential intercellular communication between every compartment is possible in the culture medium in a volume-dependent manner. For example, paracrine intercellular communication can be studied between four cell types in monolayer, in 3D (spheroids), or by combining both. In addition, a mix of different cell types can be seeded in the same compartment in 2D or 3D (organoids) format. The absence of a bottom in the 3D-printed inserts allows the usual culture conditions on the plate, possible coating on the plate containing the insert, and direct visualization by optical microscopy. The multiple compartments provide the possibility to collect different cell types independently or to use, in each compartment, different reagents for RNA or protein extraction. In this study, a detailed methodology is provided to use the new 3D-printed insert as a co-culture system. To demonstrate several capacities of this flexible and simple model, previously published functional assays of cell communication were performed in the new 3D-printed inserts and were demonstrated to be reproducible. The 3D-printed inserts and the conventional cell culture using conditioned media led to similar results. In conclusion, the 3D-printed insert is a simple device that can be adapted to numerous models of co-cultures with adherent cell types.
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Técnicas de Cultivo Tridimensional de Células , Técnicas de Cultivo de Célula , Medios de Cultivo Condicionados , Técnicas de Cultivo de Célula/métodos , Técnicas de Cocultivo , Impresión TridimensionalRESUMEN
Finding new mechanistic solutions for biocatalytic challenges is key in the evolutionary adaptation of enzymes, as well as in devising new catalysts. The recent release of man-made substances into the environment provides a dynamic testing ground for observing biocatalytic innovation at play. Phosphate triesters, used as pesticides, have only recently been introduced into the environment, where they have no natural counterpart. Enzymes have rapidly evolved to hydrolyze phosphate triesters in response to this challenge, converging onto the same mechanistic solution, which requires bivalent cations as a cofactor for catalysis. In contrast, the previously identified metagenomic promiscuous hydrolase P91, a homologue of acetylcholinesterase, achieves slow phosphotriester hydrolysis mediated by a metal-independent Cys-His-Asp triad. Here, we probe the evolvability of this new catalytic motif by subjecting P91 to directed evolution. By combining a focused library approach with the ultrahigh throughput of droplet microfluidics, we increase P91's activity by a factor of ≈360 (to a kcat/KM of ≈7 × 105 M-1 s-1) in only two rounds of evolution, rivaling the catalytic efficiencies of naturally evolved, metal-dependent phosphotriesterases. Unlike its homologue acetylcholinesterase, P91 does not suffer suicide inhibition; instead, fast dephosphorylation rates make the formation of the covalent adduct rather than its hydrolysis rate-limiting. This step is improved by directed evolution, with intermediate formation accelerated by 2 orders of magnitude. Combining focused, combinatorial libraries with the ultrahigh throughput of droplet microfluidics can be leveraged to identify and enhance mechanistic strategies that have not reached high efficiency in nature, resulting in alternative reagents with novel catalytic machineries.
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Hidrolasas , Hidrolasas de Triéster Fosfórico , Acetilcolinesterasa , Hidrolasas de Triéster Fosfórico/genética , Hidrolasas de Triéster Fosfórico/metabolismo , Biocatálisis , CatálisisRESUMEN
Heparan sulfate proteoglycans (HSPGs) are part of proteoglycan family. They are composed of heparan sulfate (HS)-type glycosaminoglycan (GAG) chains covalently linked to a core protein. By interacting with growth factors and/or receptors, they regulate numerous pathways including Wnt, hedgehog (Hh), bone morphogenic protein (BMP) and fibroblast growth factor (FGF) pathways. They act as inhibitor or activator of these pathways to modulate embryonic and adult stem cell fate during organ morphogenesis, regeneration and homeostasis. This review summarizes the knowledge on HSPG structure and classification and explores several signaling pathways regulated by HSPGs in stem cell fate. A specific focus on hair follicle stem cell fate and the possibility to target HSPGs in order to tackle hair loss are discussed in more dermatological and cosmeceutical perspectives.
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PERFECT is a multicentre randomised controlled clinical trial that evaluates the efficiency of fusion magnetic resonance imaging-targeted biopsies in the transperineal (TP) versus transrectal (TR) approach in terms of the detection of significant cancers. Our study builds on the hypothesis that the TP approach for prostate biopsies has at least the same diagnostic accuracy as the TR approach, with lower morbidity. Here, we describe the clinical protocol, study population, and primary and secondary outcomes.
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The hair renewal involves changes in the morphology of the hair follicle and its micro-vascularization. In alopecia, the hair cycle is accelerated, resulting in the formation of thinner and shorter hair. In addition, alopecia is associated with a decrease in the micro-vascularization of the hair follicles. In this study, the role of glypicans (GPCs) was analyzed in the regulation of the angiogenesis of human dermal microvascular endothelial cells (HDMEC). The analysis of glypican gene expression showed that GPC1 is the major glypican expressed by human keratinocytes of outer root sheath (KORS), human hair follicle dermal papilla cells (HHFDPC) and HDMEC. KORS were demonstrated to secrete VEGF and HGF. The HDMEC pseudotube formation was induced by KORS conditioned media (KORSCM). It was totally abrogated after GPC1 siRNA transfection of HDMEC. Moreover, when cleaved by phospholipase C (PLC), GPC1 promotes the proliferation of HDMEC. Finally, GPC1 was shown to interact directly with VEGFR2 or c-Met to regulate angiogenesis induced by the activation of these receptors. Altogether, these results showed that GPC1 is a key regulator of microvascular endothelial cell angiogenesis induced by VEGF and HGF secreted by KORS. Thus, GPC1 might constitute an interesting target to tackle alopecia in dermatology research.
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Ethylene is a small hydrocarbon gas widely used in the chemical industry. Annual worldwide production currently exceeds 150 million tons, producing considerable amounts of CO2 contributing to climate change. The need for a sustainable alternative is therefore imperative. Ethylene is natively produced by several different microorganisms, including Pseudomonas syringae pv. phaseolicola via a process catalyzed by the ethylene-forming enzyme (EFE), subsequent heterologous expression of EFE has led to ethylene production in non-native bacterial hosts including Escherichia coli and cyanobacteria. However, solubility of EFE and substrate availability remain rate-limiting steps in biological ethylene production. We employed a combination of genome-scale metabolic modelling, continuous fermentation, and protein evolution to enable the accelerated development of a high efficiency ethylene producing E. coli strain, yielding a 49-fold increase in production, the most significant improvement reported to date. Furthermore, we have clearly demonstrated that this increased yield resulted from metabolic adaptations that were uniquely linked to EFE (wild type versus mutant). Our findings provide a novel solution to deregulate metabolic bottlenecks in key pathways, which can be readily applied to address other engineering challenges.
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Escherichia coli , Biología de Sistemas , Escherichia coli/genética , Etilenos , Laboratorios , Ingeniería Metabólica , Pseudomonas syringae/genéticaRESUMEN
BACKGROUND AND OBJECTIVES: Dose selection is a key feature of clinical development. Poor dose selection has been recognized as a major driver of development failure in late phase. It usually involves both efficacy and safety criteria. The objective of this paper is to develop and implement a novel fully Bayesian statistical framework to optimize the dose selection process by maximizing the expected utility in phase III. METHODS: The success probability is characterized by means of a utility function with two components, one for efficacy and one for safety. Each component refers to a dose-response model. Moreover, a sequential design (with futility and efficacy rules at the interim analysis) is compared to a fixed design in order to allow one to hasten the decision to perform the late phase study. Operating characteristics of this approach are extensively assessed by simulations under a wide range of dose-response scenarios. RESULTS AND CONCLUSIONS: Simulation results illustrate the difficulty of simultaneously estimating two complex dose-response models with enough accuracy to properly rank doses using an utility function combining the two. The probability of making the good decision increases with the sample size. For some scenarios, the sequential design has good properties: with a quite large probability of study termination at interim analysis, it enables to reduce the sample size while maintaining the properties of the fixed design.
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Proyectos de Investigación , Teorema de Bayes , Simulación por Computador , Relación Dosis-Respuesta a Droga , Tamaño de la MuestraRESUMEN
(1) Background-The five-year overall survival (OS) of muscle-invasive bladder cancer (MIBC) with neoadjuvant chemotherapy and cystectomy is around 50%. There is no validated biomarker to guide the treatment decision. We investigated whether the Immunoscore (IS) could predict the pathologic response to neoadjuvant chemotherapy and survival outcomes. (2) Methods-This retrospective study evaluated the IS in 117 patients treated using neoadjuvant chemotherapy for localized MIBC from six centers (France and Greece). Pre-treatment tumor samples were immunostained for CD3+ and CD8+ T cells and quantified to determine the IS. The results were associated with the response to neoadjuvant chemotherapy, time to recurrence (TTR), and OS. (3) Results-Low (IS-0), intermediate (IS-1-2), and high (IS-3-4) ISs were observed in 36.5, 43.7, and 19.8% of the cohort, respectively. IS was positively associated with a pathologic complete response (pCR; p-value = 0.0096). A high IS was found in 35.7% of patients with a pCR, whereas it was found in 11.3% of patients without a pCR. A low IS was observed in 48.4% of patients with no pCR and in 21.4% of patients with a pCR. Low-, intermediate-, and high-IS patients had five-year recurrence-free rates of 37.2%, 36.5%, and 72.6%, respectively. In the multivariable analysis, a high IS was associated with a prolonged TTR (high vs. low: p = 0.0134) and OS (high vs. low: p = 0.011). (4) Conclusions-This study showed the significant prognostic and predictive roles of IS regarding localized MIBC.
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The expression of glypicans in different hair follicle (HF) compartments and their potential roles during hair shaft growth are still poorly understood. Heparan sulfate proteoglycan (HSPG) distribution in HFs is classically investigated by conventional histology, biochemical analysis, and immunohistochemistry. In this report, a novel approach is proposed to assess hair histology and HSPG distribution changes in HFs at different phases of the hair growth cycle using infrared spectral imaging (IRSI). The distribution of HSPGs in HFs was probed by IRSI using the absorption region relevant to sulfation as a spectral marker. The findings were supported by Western immunoblotting and immunohistochemistry assays focusing on the glypican-1 expression and distribution in HFs. This study demonstrates the capacity of IRSI to identify the different HF tissue structures and to highlight protein, proteoglycan (PG), glycosaminoglycan (GAG), and sulfated GAG distribution in these structures. The comparison between anagen, catagen, and telogen phases shows the qualitative and/or quantitative evolution of GAGs as supported by Western immunoblotting. Thus, IRSI can simultaneously reveal the location of proteins, PGs, GAGs, and sulfated GAGs in HFs in a reagent- and label-free manner. From a dermatological point of view, IRSI shows its potential as a promising technique to study alopecia.
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Glicosaminoglicanos/metabolismo , Glipicanos/metabolismo , Cabello/crecimiento & desarrollo , Proteoglicanos de Heparán Sulfato/metabolismo , Algoritmos , Alopecia/diagnóstico , Alopecia/prevención & control , Biopsia , Western Blotting , Análisis por Conglomerados , Dermatología , Proteínas de la Matriz Extracelular , Cabello/metabolismo , Folículo Piloso/metabolismo , Humanos , Immunoblotting , Inmunohistoquímica , Análisis de Componente Principal , Espectrofotometría Infrarroja/métodosRESUMEN
PURPOSE: To assess the association between PD-L1 expression and disease-free survival (DFS) in High-Risk Non-Muscle Invasive Bladder Cancer (HR-NMIBC) patients treated with intravesical Bacillus Calmette-Guerin (BCG) instillations (IBI). METHODS: Retrospective study in five French centres between 2001 and 2015. Participants were 140 patients with histologically confirmed HR-NMIBC. All patients received induction and maintenance IBI. Pathological stage/grade, concomitant carcinoma in situ, lesion number and tumour size were recorded. CD3, CD8 and PD-L1 expression in tumour cells and in T cells in the tumour microenvironment (TME) was determined immunohistochemically. Median follow-up was 54.2 months. The primary outcome measure was DFS. Univariable and multivariable analyses were performed using the log rank test and Cox proportional hazards model. RESULTS: Of the 140 NMIBC, 52 (37.1%) were Ta, 88 (62.9%) were T1 and 100% were high grade. Median number of maintenance IBI was six (range 1-30). Twenty-five (17.9%) patients had recurrence/progression. In multivariable analysis, age (HR 1.07 [95% CI 1.02-1.13], p = 0.009), PD-L1 expression in tumour cells (HR per 10 units = 1.96 [95% CI 1.28-3.00], p = 0.02) and CD3/CD8 ratio (HR per 10 units = 3.38 [95% CI 1.61-7.11], p = 0.01) were significantly associated with DFS. However, using the cut-off corresponding for each PD-L1 antibodies, PD-L1 + status was not associated with DFS. CONCLUSION: Despite an association between PD-L1 expression and BCG failure in HR-NMIBC, the PD-L1 + status was not a prognostic factor in the response of BCG. Moreover, we confirmed the key role played by the IC within the microenvironment in BCG treatment. These findings highlighted the rationale to combine BCG and PD-L1/PD-1 antibodies in early bladder cancer.
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Adyuvantes Inmunológicos/administración & dosificación , Antígeno B7-H1 , Vacuna BCG/administración & dosificación , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/inmunología , Administración Intravesical , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/biosíntesis , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos , Medición de Riesgo , Linfocitos T/metabolismo , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patologíaRESUMEN
INTRODUCTION: The objective of this study was to evaluate the performance of different tumor diameters for identifying ≥ pT2 upper tract urothelial carcinoma (UTUC) at radical nephroureterectomy. PATIENTS AND METHODS: This was a multi-institutional retrospective study that included 932 patients who underwent radical nephroureterectomy for nonmetastatic UTUC between 2000 and 2016. Tumor sizes were pathologically assessed and categorized into 4 groups: ≤ 1 cm, 1.1 to 2 cm, 2.1 to 3 cm, and > 3 cm. We performed logistic regression and decision-curve analyses. RESULTS: Overall, 45 (4.8%) patients had a tumor size ≤ 1 cm, 141 (15.1%) between 1.1 and 2 cm, 247 (26.5%) between 2.1 and 3 cm, and 499 (53.5%) > 3 cm. In preoperative predictive models that were adjusted for the effects of standard clinicopathologic features, tumor diameters > 2 cm (odds ratio, 2.38; 95% confidence interval, 1.70-3.32; P < .001) and > 3 cm (odds ratio, 1.81; 95% confidence interval, 1.38-2.38; P < .001) were independently associated with ≥ pT2 pathologic staging. The addition of the > 2-cm diameter cutoff improved the area under the curve of the model from 58.8% to 63.0%. Decision-curve analyses demonstrated a clinical net benefit of 0.09 and a net reduction of 8 per 100 patients. CONCLUSION: The 2-cm cutoff appears to be most useful in identifying patients at risk of harboring ≥ pT2 UTUC. This confirms the current European Association of Urology guideline's risk stratification. Tumor size alone is not sufficient for optimal risk stratification, rather a constellation of features is needed to select the best candidate for kidney-sparing surgery.
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Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Carcinoma de Células Transicionales/cirugía , Humanos , Nefroureterectomía , Pronóstico , Estudios Retrospectivos , Medición de RiesgoRESUMEN
RNA-based drugs are an emerging class of therapeutics combining the immense potential of DNA gene-therapy with the absence of genome integration-associated risks. While the synthesis of such molecules is feasible, large scale in vitro production of humanised mRNA remains a biochemical and economical challenge. Human mRNAs possess two post-transcriptional modifications at their 5' end: an inverted methylated guanosine and a unique 2'O-methylation on the ribose of the penultimate nucleotide. One strategy to precisely methylate the 2' oxygen is to use viral mRNA methyltransferases that have evolved to escape the host's cell immunity response following virus infection. However, these enzymes are ill-adapted to industrial processes and suffer from low turnovers. We have investigated the effects of homologous and orthologous active-site mutations on both stability and transferase activity, and identified new functional motifs in the interaction network surrounding the catalytic lysine. Our findings suggest that despite their low catalytic efficiency, the active-sites of viral mRNA methyltransferases have low mutational plasticity, while mutations in a defined third shell around the active site have strong effects on folding, stability and activity in the variant enzymes, mostly via network-mediated effects.
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Metiltransferasas , ARN Mensajero , ARN Viral , Virus Vaccinia , Proteínas no Estructurales Virales , Dominio Catalítico , Humanos , Metilación , Metiltransferasas/química , Metiltransferasas/genética , Metiltransferasas/metabolismo , ARN Mensajero/química , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/química , ARN Viral/genética , ARN Viral/metabolismo , Virus Vaccinia/enzimología , Virus Vaccinia/genética , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismoRESUMEN
BACKGROUND: Despite the importance of the mucosal interface between microbiota and the host in gut homeostasis, little is known about the mechanisms of bacterial gut colonization, involving foraging for glycans produced by epithelial cells. The slow pace of progress toward understanding the underlying molecular mechanisms is largely due to the lack of efficient discovery tools, especially those targeting the uncultured fraction of the microbiota. RESULTS: Here, we introduce an ultra-high-throughput metagenomic approach based on droplet microfluidics, to screen fosmid libraries. Thousands of bacterial genomes can be covered in 1 h of work, with less than ten micrograms of substrate. Applied to the screening of the mucosal microbiota for ß-N-acetylgalactosaminidase activity, this approach allowed the identification of pathways involved in the degradation of human gangliosides and milk oligosaccharides, the structural homologs of intestinal mucin glycans. These pathways, whose prevalence is associated with inflammatory bowel diseases, could be the result of horizontal gene transfers with Bacteroides species. Such pathways represent novel targets to study the microbiota-host interactions in the context of inflammatory bowel diseases, in which the integrity of the mucosal barrier is impaired. CONCLUSION: By compartmentalizing experiments inside microfluidic droplets, this method speeds up and miniaturizes by several orders of magnitude the screening process compared to conventional approaches, to capture entire metabolic pathways from metagenomic libraries. The method is compatible with all types of (meta)genomic libraries, and employs a commercially available flow cytometer instead of a custom-made sorting system to detect intracellular or extracellular enzyme activities. This versatile and generic workflow will accelerate experimental exploration campaigns in functional metagenomics and holobiomics studies, to further decipher host-microbiota relationships. Video Abstract.
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Interacciones Microbiota-Huesped , Microbiota/fisiología , Microfluídica , Bacterias/genética , Humanos , Masculino , Metagenómica , Microbiota/genética , Persona de Mediana EdadRESUMEN
BACKGROUND: Radical nephroureterectomy (RNU) is the referent standard for managing bulky, invasive, or high grade upper-tract urothelial carcinoma (UTUC). The UTUC patient population, however, generally harbor medical comorbidities thereby placing them at risk of surgical complications. This study reviews a large international cohort of RNU patients to define the risk of major complications and preoperative factors associated with their occurrence. METHODS: Patients undergoing RNU at 14 academic medical centers between 2002 and 2015 were retrospectively reviewed. Preoperative clinical, demographic, operative, and comorbidity indices were recorded. The modified Clavien-Dindo index was used to grade complications occurring within 30 days of surgery. The association between preoperative variables and major complications occurring after RNU was determined by multivariable logistic regression. RESULTS: One thousand two hundred and sixty-six patients (707 men; 559 women) with a median age of 70 years and BMI of 27 kg/m2 were included. Over three-quarters of the cohort was white, 50.1% had baseline chronic kidney disease (CKD) ≥ stage III, 22.4% had a Charlson comorbidity index (CCI) score >5, and 17.1% had an Eastern Cooperative Oncology Group (ECOG) performance status ≥2. Overall, 413 (32.6%) experienced a complication including 103 (8.1%) with a major event. Specific distribution of major complications included 49 Clavien III, 44 Clavien IV, and 10 Clavien V. On univariate analysis, patient age (P=0.006), hypertension (P=0.002), diabetes mellitus (P=0.023), CKD stage (P<0.001), American Society of Anesthesiologists (ASA) score (P=0.022), ECOG (P<0.001), and CCI (P<0.001) all were associated with major complications. On multivariate analysis, ECOG ≥2 (OR 2.38, 95% CI, 1.46-3.90), P=0.001), CCI >5 (OR 3.45, 95% CI, 1.41-8.33, P=0.007), and CKD stage ≥3 (OR 3.64, P=0.008) were independently associated with major complications. CONCLUSIONS: Major complications following RNU occurred in almost 10% of patients. Impaired preoperative performance status and baseline CKD are preoperative variables associated with these major post-surgical adverse event. These easily measurable indices warrant consideration and discussion prior to proceeding with RNU.
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Proteoglycans (PG) play an important role in maintaining the extracellular matrix (ECM) integrity. Lumican, a small leucine rich PG, is one such actor capable of regulating such properties. In this study, the integrity of the dermis of lumican-deleted Lum -/- vs. wild-type mice was investigated by conventional histology and by infrared spectral histology (IRSH). Infrared spectroscopy is a non-invasive, rapid, label-free and sensitive technique that allows to probe molecular vibrations of biomolecules present in a tissue. Our IRSH results obtained on control (WT, n = 3) and Lum -/- (n = 3) mice showed that different histological structures were identified by using K-means clustering and validated by hematoxylin eosin saffron (HES) staining. Furthermore, an important increase of the dermis thickness was observed in Lum -/- compared to WT mice. In terms of structural information, analysis of the spectral images also revealed an intra-group homogeneity and inter-group heterogeneity. In addition, type I collagen contribution was evaluated by HES and picrosirius red staining as well as with IRSH. Both techniques showed a strong remodeling of the ECM in Lum -/- mice due to the looseness of collagen fibers in the increased dermis space. These results confirmed the impact of lumican on the ECM integrity. The loss of collagen fibers organization due to the absence of lumican can potentially increase the accessibility of anti-cancer drugs to the tumor. These results are qualitatively interesting and would need further structural characterization of type I collagen fibers in terms of size, organization, and orientation.
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The wide and fast spread of COVID-19 around the world has led to a dramatic increase in the need for protection products both for carers and for populations. Surgical team protection includes a systematic screening of patients, wearing protection devices by all the operating staff, and adequate management of aerosols. The risk of aerosol dispersal is particularly high during laparoscopic and robotic surgeries due to the interaction between circulating CO2 and surgical smoke that may contain small viral particles. To decrease the risk of virus transmission, many recommendations have been implemented including the use of integrated insufflation devices comprising smoke evacuation and filtration mode. Such devices are lacking in many centers around the world and to overcome this urgent unmet need, we designed a cost-effective filtrating suction as a more readily available alternative.