RESUMEN
As in human cells, yeast telomeres can be maintained in cells lacking telomerase activity by recombination-based mechanisms known as ALT (Alternative Lengthening of Telomeres). A hallmark of ALT human cancer cells are extrachromosomal telomeric DNA elements called C-circles, whose origin and function have remained unclear. Here, we show that extrachromosomal telomeric C-circles in yeast can be detected shortly after senescence crisis and concomitantly with the production of survivors arising from "type II" recombination events. We uncover that C-circles bind to the nuclear pore complex (NPC) and to the SAGA-TREX2 complex, similar to other non-centromeric episomal DNA. Disrupting the integrity of the SAGA/TREX2 complex affects both C-circle binding to NPCs and type II telomere recombination, suggesting that NPC tethering of C-circles facilitates formation and/or propagation of the long telomere repeats characteristic of type II survivors. Furthermore, we find that disruption of the nuclear diffusion barrier impairs type II recombination. These results support a model in which concentration of C-circles at NPCs benefits type II telomere recombination, highlighting the importance of spatial coordination in ALT-type mechanisms of telomere maintenance.
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Poro Nuclear , Saccharomyces cerevisiae , Citoplasma , Humanos , Poro Nuclear/genética , Saccharomyces cerevisiae/genética , Telómero/genéticaRESUMEN
R loops are an important source of genome instability, largely due to their negative impact on replication progression. Yra1/ALY is an abundant RNA-binding factor conserved from yeast to humans and required for mRNA export, but its excess causes lethality and genome instability. Here, we show that, in addition to ssDNA and ssRNA, Yra1 binds RNA-DNA hybrids in vitro and, when artificially overexpressed, can be recruited to chromatin in an RNA-DNA hybrid-dependent manner, stabilizing R loops and converting them into replication obstacles in vivo. Importantly, an excess of Yra1 increases R-loop-mediated genome instability caused by transcription-replication collisions regardless of whether they are codirectional or head-on. It also induces telomere shortening in telomerase-negative cells and accelerates senescence, consistent with a defect in telomere replication. Our results indicate that RNA-DNA hybrids form transiently in cells regardless of replication and, after stabilization by excess Yra1, compromise genome integrity, in agreement with a two-step model of R-loop-mediated genome instability. This work opens new perspectives to understand transcription-associated genome instability in repair-deficient cells, including tumoral cells.
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Inestabilidad Cromosómica/genética , Replicación del ADN , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Telómero/genética , Transcripción Genética , Cromatina/metabolismo , Hibridación de Ácido Nucleico , Unión Proteica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Telómero/metabolismoRESUMEN
Individual differences in delay discounting-how much we discount future compared to immediate rewards-are associated with general life outcomes, psychopathology, and obesity. Here, we use machine learning on fMRI activity during an intertemporal choice task to develop a functional brain marker of these individual differences in human adults. Training and cross-validating the marker in one dataset (Study 1, N = 110 male adults) resulted in a significant prediction-outcome correlation (r = 0.49), generalized to predict individual differences in a completely independent dataset (Study 2: N = 145 male and female adults, r = 0.45), and predicted discounting several weeks later. Out-of-sample responses of the functional brain marker, but not discounting behavior itself, differed significantly between overweight and lean individuals in both studies, and predicted fasting-state blood levels of insulin, c-peptide, and leptin in Study 1. Significant predictive weights of the marker were found in cingulate, insula, and frontoparietal areas, among others, suggesting an interplay among regions associated with valuation, conflict processing, and cognitive control. This new functional brain marker is a step toward a generalizable brain model of individual differences in delay discounting. Future studies can evaluate it as a potential transdiagnostic marker of altered decision-making in different clinical and developmental populations.SIGNIFICANCE STATEMENT People differ substantially in how much they prefer smaller sooner rewards or larger later rewards such as spending money now versus saving it for retirement. These individual differences are generally stable over time and have been related to differences in mental and bodily health. What is their neurobiological basis? We applied machine learning to brain-imaging data to identify a novel brain activity pattern that accurately predicts how much people prefer sooner versus later rewards, and which can be used as a new brain-based measure of intertemporal decision-making in future studies. The resulting functional brain marker also predicts overweight and metabolism-related blood markers, providing new insight into the possible links between metabolism and the cognitive and brain processes involved in intertemporal decision-making.
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Descuento por Demora , Adulto , Humanos , Masculino , Femenino , Descuento por Demora/fisiología , Imagen por Resonancia Magnética/métodos , Individualidad , Sobrepeso , Encéfalo/fisiología , RecompensaRESUMEN
Sensory deprivation, especially hearing loss (HL), offers a valuable model for studying neuroplasticity in the human brain and adaptive behaviours that support the daily lives of those with limited or absent sensory input. The study of olfactory function is particularly important as it is an understudied aspect of sensory deprivation. This study aimed to compare the effects of congenital HL on olfactory capacity by using psychophysical tasks. Methodological concerns from previous studies regarding the onset of HL and cognitive assessments were addressed. We recruited 11 individuals with severe-to-profound sensorineural HL (SNHL) since birth and 11 age- and sex-matched typical hearing non-signers. We used standardized neuropsychological tests to assess typical cognition among participants with SNHL. We evaluated olfactory functions by assessing olfactory detection threshold, odour discrimination and odour identification. Hearing-impaired participants outperformed their typical hearing counterparts in olfactory tasks. We further evaluated the accuracy and response time in identifying and localizing odours to disentangle olfactory sensitivity from trigeminal system sensitivity. Participants with SNHL demonstrated higher sensitivity to both the identification and localization tasks. These findings suggest that congenital SNHL is associated with enhanced higher-level olfactory processing and increased trigeminal sensitivity.
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Sordera , Pérdida Auditiva Sensorineural , Percepción Olfatoria , Humanos , Olfato/fisiología , Odorantes , PercepciónRESUMEN
BACKGROUND: Palm oil (PO) is the most widely utilized plant oil for food production. Owing to the great ecologic problems associated with PO production, sustainably produced fats, such as insect fat, might be a suitable alternative. OBJECTIVES: The hypothesis was tested that fat from Hermetia illucens larvae (HF) compared with PO and soybean oil (SO) has no adverse effects on hepatic lipid metabolism, plasma metabolome, and cecal microbiome in obese Zucker rats. METHODS: Thirty male obese Zucker rats were randomly assigned to 3 groups (SO, PO, HF; n = 10 rats/group) and fed 3 different semisynthetic diets containing either SO, PO, or HF as the main fat source for 4 wk. The effects were evaluated by measurement of liver and plasma lipid concentrations, liver transcriptomics, targeted plasma metabolomics, and cecal microbiomics. RESULTS: Supplementation of HF reduced hepatic triglyceride concentration and messenger ribonucleic acid concentrations of selected genes involved in fatty acid and triglyceride synthesis in comparison to PO (P < 0.05). Pairwise comparison of the Simpson index and Jaccard index showed a higher cecal microbial α- and ß-diversity in rats fed the HF diet than in rats fed the PO diet (P = 0.015 and P = 0.027), but no difference between rats fed the diets with SO or PO. Taxonomic analysis of the cecal microbial community revealed a lower abundance of Clostridium_sensu_stricto_1 and a higher abundance of Blautia, Mucispirillum, Anaerotruncus, Harryflintia, and Peptococcus in rats supplemented with HF than in rats supplemented with PO (P < 0.05). CONCLUSIONS: HF, compared with PO, has liver lipid-lowering effects in obese Zucker rats, which may be caused by a shift in the gut microbial community. Thus, HF might serve as a sustainably produced fat alternative to PO for food production.
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Dípteros , Microbioma Gastrointestinal , Ratas , Animales , Triglicéridos , Aceite de Palma , Ratas Zucker , Grasas de la Dieta/farmacología , Obesidad/metabolismo , Hígado/metabolismo , Aceite de Soja , Dípteros/metabolismoRESUMEN
BACKGROUND: Ventilator associated pneumonia (VAP) due to wild-type AmpC-producing Enterobacterales (wtAE) is frequent in intensive care unit (ICU) patients. Despite a low level of evidence, definitive antimicrobial therapy (AMT) with third generation cephalosporins (3GCs) or piperacillin is discouraged. METHODS: Observational prospective study including consecutive wtAE VAP patients in 20 French ICUs. The primary objective was to assess the association of the choice of definitive AMT, i.e. piperacillin ± tazobactam (PTZ), 3GCs or other molecule (4GCs, carbapenems, quinolones, cotrimoxazole; control group), with treatment success at day-7. Recurrence of infection was collected as a secondary outcome, and analyzed accounting for the competing risk of death. RESULTS: From February 2021 to June 2022, 274 patients were included. Enterobacter cloacae was the most prevalent specie (31%). Seventy-eight patients (28%) had PTZ as definitive AMT while 44 (16%) had 3GCs and 152 (56%) were classified in the control group. Day-7 success rate was similar between the 3 groups (74% vs. 73% vs. 68% respectively, p = 0.814). Recurrence probability at day-28 was 31% (95% CI 21-42), 40% (95% CI 26-55) and 21% (95% CI 15-28) for PTZ, 3GCs and control groups (p = 0.020). In multivariable analysis, choice of definitive AMT was not associated with clinical success, but definitive AMT with 3GCs was associated with recurrence at day-28 [csHR(95%CI) 10.9 (1.92-61.91)]. CONCLUSION: Choice of definitive antimicrobial therapy was not associated with treatment success at day 7. However, recurrence of pneumonia at day-28 was higher in patients treated with third generation cephalosporins with no differences in mortality or mechanical ventilation duration.
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Antibacterianos , Neumonía Asociada al Ventilador , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Estudios Prospectivos , Neumonía Asociada al Ventilador/tratamiento farmacológico , Enfermedad Crítica/terapia , Piperacilina/uso terapéutico , Combinación Piperacilina y Tazobactam/uso terapéutico , Unidades de Cuidados IntensivosRESUMEN
INTRODUCTION: Blood biomarkers accurately identify Alzheimer's disease (AD) pathophysiology and axonal injury. We investigated the influence of food intake on AD-related biomarkers in cognitively healthy, obese adults at high metabolic risk. METHODS: One-hundred eleven participants underwent repeated blood sampling during 3 h after a standardized meal (postprandial group, PG). For comparison, blood was sampled from a fasting subgroup over 3 h (fasting group, FG). Plasma neurofilament light (NfL), glial fibrillary acidic protein (GFAP), amyloid-beta (Aß) 42/40, phosphorylated tau (p-tau) 181 and 231, and total-tau were measured via single molecule array assays. RESULTS: Significant differences were found for NfL, GFAP, Aß42/40, p-tau181, and p-tau231 between FG and PG. The greatest change to baseline occurred for GFAP and p-tau181 (120 min postprandially, p < 0.0001). CONCLUSION: Our data suggest that AD-related biomarkers are altered by food intake. Further studies are needed to verify whether blood biomarker sampling should be performed in the fasting state. HIGHLIGHTS: Acute food intake alters plasma biomarkers of Alzheimer's disease in obese, otherwise healthy adults. We also found dynamic fluctuations in plasma biomarkers concentration in the fasting state suggesting physiological diurnal variations. Further investigations are highly needed to verify if biomarker measurements should be performed in the fasting state and at a standardized time of day to improve the diagnostic accuracy.
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Enfermedad de Alzheimer , Adulto , Humanos , Enfermedad de Alzheimer/diagnóstico , Proyectos Piloto , Péptidos beta-Amiloides , Proteínas tau , Biomarcadores , Obesidad , Ingestión de AlimentosRESUMEN
BACKGROUND: Cervical cancer screening tests that identify DNA of the main causal agent, high-risk human papillomavirus (HPV) types, are more protective than cervical cytology. We systematically reviewed the literature to assess whether tests targeting high-risk HPV (hrHPV) mRNA are as accurate and effective as HPV DNA-based screening tests. METHODS: We did a systematic review to assess the cross-sectional clinical accuracy to detect cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) or 3 or worse (CIN3+) of hrHPV mRNA versus DNA testing in primary cervical cancer screening; the longitudinal clinical performance of cervical cancer screening using hrHPV mRNA versus DNA assays; and the clinical accuracy of hrHPV mRNA testing on self-collected versus clinician-collected samples. We identified relevant studies published before Aug 1, 2021, through a search of Medline (PubMed), Embase, and CENTRAL. Eligible studies had to contain comparative data addressing one of our three clinical questions. Aggregated data were extracted from selected reports or requested from study authors if necessary. QUADAS and ROBINS-1 tools were used to assess the quality of diagnostic test accuracy studies and cohort studies. To assess cross-sectional clinical accuracy of mRNA testing versus DNA testing and clinical accuracy of hrHPV mRNA testing on self-collected versus clinician collected samples, we applied meta-analytical methods for comparison of diagnostic tests. To assess the longitudinal clinical performance of cervical cancer screening using hrHPV mRNA versus DNA assays, we compared the longitudinal sensitivity of mRNA tests and validated DNA tests for CIN3+ and the relative detection of CIN3+ among women who screened negative for hrHPV mRNA or DNA (both used as measures of safety) at baseline and pooled estimates by years of follow-up. A random-effect model for pooling ratios of proportions or risks was used to summarise longitudinal performance. FINDINGS: For the hrHPV mRNA testing with APTIMA HPV Test (APTIMA), the cross-sectional accuracy could be compared with DNA assays on clinician-collected samples in eight studies; longitudinal performance was compared in four studies; and accuracy on self-samples was assessed in five studies. Few reports were retrieved for other mRNA assays, precluding their evaluation in meta-analyses. Compared with validated DNA assays, APTIMA was similarly sensitive (relative sensitivity 0·98 [95% CI 0·95-1·01]) and slightly more specific (1·03 [1·02-1·04]) for CIN2+. The relative sensitivity for CIN3+ was 0·98 (95% CI 0·95-1·01). The longitudinal relative sensitivity for CIN3+ of APTIMA compared with DNA assays assessed over 4-7 years ranged at the study level from 0·91 to 1·05 and in the pooled analysis between 0·95 and 0·98, depending on timepoint, with CIs including or close to unity. The detection rate ratios between 4 and 10 years after baseline negative mRNA versus negative DNA screening were imprecise and heterogeneous among studies, but summary ratios did not differ from unity. In self-collected samples, APTIMA was less sensitive for CIN2+ (relative cross-sectional sensitivity 0·84 [0·74-0·96]) but similarly specific (relative specificity 0·96 [0·91-1·01]) compared with clinician-collected samples. INTERPRETATION: HrHPV RNA testing with APTIMA had similar cross-sectional sensitivity for CIN2+ and CIN3+ and slightly higher specificity than DNA tests. Four studies with 4-7 years of follow-up showed heterogeneous safety outcomes. One study with up to 10 years of follow-up showed no differences in cumulative detection of CIN3+ after negative mRNA versus DNA screening. APTIMA could be accepted for primary cervical cancer screening on clinician-collected cervical samples at intervals of around 5 years. APTIMA is less sensitive on self-collected samples than clinician-collected samples. FUNDING: Horizon 2020 Framework Programme for Research and Innovation of the European Commission, through the RISCC Network, WHO, Haute Autorité de la Santé, European Society of Gynaecological Oncology, and the National Institute of Public Health and the Environment.
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Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Estudios Transversales , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Tamizaje Masivo , Papillomaviridae/genética , Infecciones por Papillomavirus/diagnóstico , ARN Mensajero/genética , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/prevención & control , Frotis Vaginal/métodosRESUMEN
BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is frequent among patients undergoing bariatric surgery. Beyond weight reduction, dietary supplements like micronutrients or probiotics that modify insulin resistance and lipotoxicity can be used to prevent or delay the progression of liver disease. OBJECTIVES: We evaluated the effect of a dietary approach with a specifically tailored multistrain probiotic and micronutrient mixture compared with a basic care micronutrient supplement on serum alanine aminotransferase (ALAT) in obese patients after mini gastric bypass (MGB) surgery. METHODS: This randomized, double-blind, controlled trial included 60 obese patients (age: 40 ± 10 y; BMI: 44 ± 3 kg/m²). Patients received a combination of specifically tailored multistrain probiotic powder and a specific micronutrient mixture (Pro+SM) or a control treatment consisting of a placebo and a basic care micronutrient mixture (Con+BM), with some micronutrients in lower doses than SM, for 12 wk after hospital discharge. Primary (serum ALAT) and secondary outcomes [serum aspartate aminotransferase (ASAT), fatty liver index, NAFLD fibrosis score, glucose metabolism, blood pressure (BP), heart rate] were assessed at week 0 and week 12. Data were analyzed using unpaired Student's t-tests or Mann-Whitney U tests to compare the changes due to each treatment to one another. RESULTS: A total of 48 patients were included in the analyses. Changes in serum ALAT concentrations did not differ between groups. Compared with Con+BM, Pro+SM improved serum ASAT (difference: -8.0 U/L, 95% CI: -17.0, -4.0; P = 0.043), NAFLD fibrosis score (difference: -0.39; 95% CI: -0.78, 0; P = 0.048), serum triglycerides (difference: -22.8 mg/dL; 95% CI: -45.6, -0.1; P = 0.049) and the visceral adiposity index (difference: -0.70; 95% CI: -1.31, -0.08; P = 0.027). CONCLUSION: Supplementation with a specifically tailored probiotic and micronutrient mixture improved NAFLD-related markers more than a basic micronutrient mixture in obese patients following MGB surgery. The trial was registered under clinicaltrials.gov as NCT03585413.
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Derivación Gástrica , Enfermedad del Hígado Graso no Alcohólico , Probióticos , Adulto , Humanos , Micronutrientes/uso terapéutico , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Obesidad/complicaciones , Probióticos/uso terapéuticoRESUMEN
Circulating levels of the amino acid glutamate are associated with central fat accumulation, yet the pathophysiology of this relationship remains unknown. We aimed to (i) refine and validate the association between circulating glutamate and abdominal obesity in a large twin cohort, and (ii) investigate whether transcriptomic profiles in adipose tissue could provide insight into the biological mechanisms underlying the association. First, in a cohort of 4665 individuals from the TwinsUK resource, we identified individuals with abdominal obesity and compared prevalence of the latter across circulating glutamate quintiles. Second, we used transcriptomic signatures generated from adipose tissue, both subcutaneous and visceral, to investigate associations with circulating glutamate levels. Individuals in the top circulating glutamate quintile had a sevenfold higher prevalence of abdominal obesity compared to those in the bottom quintile. The adipose tissue transcriptomic analyses identified GLUL, encoding Glutamate-Ammonia Ligase, as being associated with circulating glutamate and abdominal obesity, with pronounced signatures in the visceral depot. In conclusion, circulating glutamate is positively associated with the prevalence of abdominal obesity which relates to dysregulated GLUL expression specifically in visceral adipose tissue.
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Ácido Glutámico , Obesidad Abdominal , Tejido Adiposo/metabolismo , Índice de Masa Corporal , Expresión Génica , Humanos , Obesidad/metabolismo , Obesidad Abdominal/genéticaRESUMEN
PURPOSE OF REVIEW: Prone position has been widely used in the COVID-19 pandemic, with an extension of its use in patients with spontaneous breathing ('awake prone'). We herein propose a review of the current literature on prone position in mechanical ventilation and while spontaneous breathing in patients with COVID-19 pneumonia or COVID-19 ARDS. RECENT FINDINGS: A literature search retrieved 70 studies separating whether patient was intubated (24 studies) or nonintubated (46 studies). The outcomes analyzed were intubation rate, mortality and respiratory response to prone. In nonintubated patient receiving prone position, the main finding was mortality reduction in ICU and outside ICU setting. SUMMARY: The final results of the several randomized control trials completed or ongoing are needed to confirm the trend of these results. In intubated patients, observational studies showed that responders to prone in terms of oxygenation had a better survival than nonresponders.
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COVID-19 , Síndrome de Dificultad Respiratoria , Insuficiencia Respiratoria , Humanos , Pandemias , Posición Prona , Respiración Artificial/efectos adversos , Síndrome de Dificultad Respiratoria/terapia , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , SARS-CoV-2RESUMEN
OBJECTIVE: To compare old patients hospitalized in ICU for respiratory distress due to COVID-19 with old patients hospitalized in ICU for a non-COVID-19-related reason in terms of autonomy and quality of life. DESIGN: Comparison of two prospective multi-centric studies. SETTING: This study was based on two prospective multi-centric studies, the Senior-COVID-Rea cohort (COVID-19-diagnosed ICU-admitted patients aged over 60) and the FRAGIREA cohort (ICU-admitted patients aged over 70). PATIENTS: We included herein the patients from both cohorts who had been evaluated at day 180 after admission (ADL score and quality of life). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 93 COVID-19 patients and 185 control-ICU patients were included. Both groups were not balanced on age, body mass index, mechanical ventilation, length of ICU stay, and ADL and SAPS II scores. We modeled with ordered logistic regression the influence of COVID-19 on the quality of life and the ADL score. After adjustment on these factors, we observed COVID-19 patients were less likely to have a loss of usual activities (aOR [95% CI] 0.47 [0.23; 0.94]), a loss of mobility (aOR [95% CI] 0.30 [0.14; 0.63]), and a loss of ADL score (aOR [95% CI] 0.30 [0.14; 0.63]). On day 180, 52 (56%) COVID-19 patients presented signs of dyspnea, 37 (40%) still used analgesics, 17 (18%) used anxiolytics, and 14 (13%) used antidepressant. CONCLUSIONS: COVID-19-related ICU stay was not associated with a lower quality of life or lower autonomy compared to non-COVID-19-related ICU stay.
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COVID-19 , Calidad de Vida , Cuidados Posteriores , Anciano , Cuidados Críticos , Humanos , Unidades de Cuidados Intensivos , Evaluación de Resultado en la Atención de Salud , Alta del Paciente , Estudios ProspectivosRESUMEN
PURPOSE: Impaired glucose tolerance (IGT) is a pathophysiological condition characterized by insulin resistance with known metabolic consequences such as postprandial hyperglycemia and hypertriglyceridemia. We hypothesized that fortifying a meal with mushrooms rich in ß-glucans may diminish glucose and triglyceride responses by improving postprandial gastrointestinal hormone release. METHODS: In a randomized controlled crossover study, 22 subjects with IGT ingested a meal either enriched with 20 g powder (8.1 g ß-glucans) of oven-dried Pleurotus ostreatus (enriched meal, EN) or without enrichment (control meal, CON). Blood was collected before and repeatedly within 4 h after the meal to determine AUC of glucose (primary outcome), insulin, triglycerides, non-esterified free fatty acids (NEFAs), glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP) and ghrelin. Appetite sensations (hunger, satiety, fullness, and desire to eat) were assessed before and after meal consumption by visual analog scales. RESULTS: Postprandial glucose, insulin, triglycerides, GIP and ghrelin concentrations as well as the corresponding AUCs did not differ between EN and CON. NEFAs-AUC was 14% lower (P = 0.026) and GLP-1-AUC 17% higher (P = 0.001) after EN compared to CON. Appetite ratings did not differ between treatments, except for hunger (AUC 22% lower after EN vs. CON; P = 0.031). CONCLUSION: The observed immediate postprandial metabolic changes indicate that an easily manageable fortification of a single meal with powder from dried oyster mushrooms as ß-glucan source may improve postprandial metabolism. If the effect is preserved long term, this measure can diminish the risk for further development of overweight/obesity and type 2 diabetes in subjects with IGT. CLINICAL TRIAL REGISTRATION: German Clinical Trial Register on 09/08/2018; trial-ID: DRKS00015244.
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Diabetes Mellitus Tipo 2 , Intolerancia a la Glucosa , Pleurotus , Adulto , Glucemia/metabolismo , Estudios Cruzados , Ácidos Grasos no Esterificados , Péptido 1 Similar al Glucagón , Intolerancia a la Glucosa/prevención & control , Humanos , Hambre , Insulina , Periodo Posprandial , Polvos , SensaciónRESUMEN
The rising prevalence of type 1 diabetes (T1D) over the past decades has been linked to lifestyle changes, but the underlying mechanisms are largely unknown. Recent findings point to gut-associated mechanisms in the control of T1D pathogenesis. In nonobese diabetic (NOD) mice, a model of T1D, diabetes development accelerates after deletion of the Toll-like receptor 4 (TLR4). We hypothesized that altered intestinal functions contribute to metabolic alterations, which favor accelerated diabetes development in TLR4-deficient (TLR4-/-) NOD mice. In 70-90-day-old normoglycemic (prediabetic) female NOD TLR4+/+ and NOD TLR4-/- mice, gut morphology and microbiome composition were analyzed. Parameters of lipid metabolism, glucose homeostasis, and mitochondrial respiratory activity were measured in vivo and ex vivo Compared with NOD TLR4+/+ mice, NOD TLR4-/- animals showed lower muscle mass of the small intestine, higher abundance of Bacteroidetes, and lower Firmicutes in the large intestine, along with lower levels of circulating short-chain fatty acids (SCFA). These changes are associated with higher body weight, hyperlipidemia, and severe insulin and glucose intolerance, all occurring before the onset of diabetes. These mice also exhibited insulin resistance-related abnormalities of energy metabolism, such as lower total respiratory exchange rates and higher hepatic oxidative capacity. Distinct alterations of gut morphology and microbiota composition associated with reduction of circulating SCFA may contribute to metabolic disorders promoting the progression of insulin-deficient diabetes/T1D development.
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Diabetes Mellitus Experimental/microbiología , Diabetes Mellitus Experimental/patología , Microbioma Gastrointestinal , Tracto Gastrointestinal/microbiología , Tracto Gastrointestinal/patología , Animales , Glucemia/metabolismo , Peso Corporal , Diabetes Mellitus Experimental/sangre , Metabolismo Energético , Ácidos Grasos/metabolismo , Homeostasis , Lipopolisacáridos/metabolismo , Hígado/patología , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Modelos Biológicos , Oxidación-Reducción , Receptor Toll-Like 4/deficiencia , Receptor Toll-Like 4/metabolismo , alfa-2-Glicoproteína-HS/metabolismoRESUMEN
OTC deficiency, an inherited urea cycle disorder, is caused by mutations in the X-linked OTC gene. Phenotype-genotype correlations are well understood in males but still poorly known in females. Taking advantage of a cohort of 130 families (289 females), we assessed the relative contribution of OTC enzyme activity, X chromosome inactivation, and OTC gene sequencing to genetic counseling in heterozygous females. Twenty two percent of the heterozygous females were clinically affected, with episodic (11%), chronic (7.5%), or neonatal forms of the disease (3.5%). Overall mortality rate was 4%. OTC activity, ranging from 0% to 60%, did not correlate with phenotype at the individual level. Analysis of multiple samples from 4 mutant livers showed intra-hepatic variability of OTC activity and X inactivation profile (range of variability: 30% and 20%, respectively) without correlation between both parameters for 3 of the 4 livers. Ninety disease-causing variants were found, 27 of which were novel. Mutations were classified as "mild" or "severe," based on male phenotypes and/or in silico prediction. In our cohort, a serious disease occurred in 32% of females with a severe mutation, compared to 4% in females with a mild mutation (odds ratio = 1.365; P = 1.6e-06). These data should help prenatal diagnosis for heterozygous females and genetic counseling after fortuitous findings of OTC variants in pangenomic sequencing.
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Mutación , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/mortalidad , Ornitina Carbamoiltransferasa/genética , Familia , Femenino , Estudios de Asociación Genética , Heterocigoto , Humanos , Hígado/enzimología , MasculinoRESUMEN
(1) Background: The atopic march is defined by the increased prevalence of allergic diseases after atopic dermatitis onset. In fact, atopic dermatitis is believed to play an important role in allergen sensitization via the damaged skin barrier, leading to allergic diseases such as allergic asthma and allergic rhinitis. The eosinophil, a pro-inflammatory cell that contributes to epithelial damage, is one of the various cells recruited in the inflammatory reactions characterizing these diseases. Few studies were conducted on the transcriptome of this cell type and even less on their specific microRNA (miRNA) profile, which could modulate pathogenesis of allergic diseases and clinical manifestations post-transcriptionally. Actually, their implication in allergic diseases is not fully understood, but they are believed to play a role in inflammation-related patterns and epithelial cell proliferation. (2) Methods: Next-generation sequencing was performed on RNA samples from eosinophils of individuals with atopic dermatitis, atopy, allergic rhinitis and asthma to obtain differential counts of primary miRNA (pri-miRNA); these were also analyzed for asthma-related phenotypes such as forced expiratory volume in one second (FEV1), immunoglobulin E (IgE) and provocative concentration of methacholine inducing a 20% fall in forced expiratory volume in 1 s (PC20) levels, as well as FEV1 to forced vital capacity (FEV1/FVC) ratio. (3) Results: Eighteen miRNAs from eosinophils were identified to be significantly different between affected individuals and unaffected ones. Based on counts from these miRNAs, individuals were then clustered into groups using Ward's method on Euclidian distances. Groups were found to be explained by asthma diagnosis, familial history of respiratory diseases and allergic rhinitis as well as neutrophil counts. (4) Conclusions: The 18 differential miRNA counts for the studying phenotypes allow a better understanding of the epigenetic mechanisms underlying the development of the allergic diseases included in the atopic march.
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Dermatitis Atópica/genética , Eosinófilos/metabolismo , Hipersensibilidad/genética , MicroARNs/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis por Conglomerados , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Fenotipo , Adulto JovenRESUMEN
BACKGROUND: Malaria transmission-blocking anti-malarial drugs, such as primaquine, offers an effective strategy for reducing the incidence of falciparum malaria. However, this drug induces haemolytic anaemia among glucose-6-phosphate dehydrogenase (G6PD) deficient individuals. The distribution of G6PD deficiency in Brazzaville, Republic of Congo and the association of G6PD deficiency with haemoglobin levels and blood cell counts were investigated. METHODS: A total of 212 febrile children were recruited for this study. Plasmodium falciparum diagnosis was conducted by microscopy and nested PCR. Sanger sequencing was used to assess G6PD deficiency by detecting 202G>A (rs1050828) and 376A>G (rs1050829) single nucleotide polymorphisms. RESULTS: Two hundred and twelve children were successfully genotyped for G6PD variants. Overall, 13% (27/212) of the children were G6PD deficient and 25% (25/100) females were heterozygous (11 BA- and 14 A+A-). The remaining 160 children had a normal G6PD genotype. The mean red blood and mean platelet counts were significantly lower in hemizygous male (G6PD A-) participants than in normal male (G6PD A+ or B) participants (p < 0.05). CONCLUSION: This study gives an update on G6PD deficiency among Congolese children. Understanding the distribution of G6PD deficiency in other geographical regions is recommended before primaquine is adopted in the malaria control programme.
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Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Niño , Preescolar , República Democrática del Congo/epidemiología , Recuento de Eritrocitos , Femenino , Técnicas de Genotipaje , Deficiencia de Glucosafosfato Deshidrogenasa/complicaciones , Deficiencia de Glucosafosfato Deshidrogenasa/patología , Humanos , Incidencia , Lactante , Malaria Falciparum/complicaciones , Malaria Falciparum/diagnóstico , Masculino , Microscopía , Parasitemia/complicaciones , Parasitemia/diagnóstico , Recuento de Plaquetas , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADNRESUMEN
Myotonic dystrophy type 1 (DM1) is a dominant multisystemic disorder associated with high variability of symptoms and anticipation. DM1 is caused by an unstable CTG repeat expansion that usually increases in successive generations and tissues. DM1 family pedigrees have shown that â¼90% and 10% of transmissions result in expansions and contractions of the CTG repeat, respectively. To date, the mechanisms of CTG repeat contraction remain poorly documented in DM1. In this report, we identified two new DM1 families with apparent contractions and no worsening of DM1 symptoms in two and three successive maternal transmissions. A new and unique CAG interruption was found in 5' of the CTG expansion in one family, whereas multiple 5' CCG interruptions were detected in the second family. We showed that these interruptions are associated with maternal intergenerational contractions and low somatic mosaicism in blood. By specific triplet-prime PCR, we observed that CTG repeat changes (contractions/expansions) occur preferentially in 3' of the interruptions for both families.
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Predisposición Genética a la Enfermedad , Mosaicismo , Distrofia Miotónica/genética , Expansión de Repetición de Trinucleótido/genética , Alelos , Femenino , Humanos , Masculino , Distrofia Miotónica/fisiopatología , Proteína Quinasa de Distrofia Miotónica/genética , LinajeRESUMEN
BACKGROUND: Antiretroviral preexposure prophylaxis has been shown to reduce the risk of human immunodeficiency virus type 1 (HIV-1) infection in some studies, but conflicting results have been reported among studies, probably due to challenges of adherence to a daily regimen. METHODS: We conducted a double-blind, randomized trial of antiretroviral therapy for preexposure HIV-1 prophylaxis among men who have unprotected anal sex with men. Participants were randomly assigned to take a combination of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) or placebo before and after sexual activity. All participants received risk-reduction counseling and condoms and were regularly tested for HIV-1 and HIV-2 and other sexually transmitted infections. RESULTS: Of the 414 participants who underwent randomization, 400 who did not have HIV infection were enrolled (199 in the TDF-FTC group and 201 in the placebo group). All participants were followed for a median of 9.3 months (interquartile range, 4.9 to 20.6). A total of 16 HIV-1 infections occurred during follow-up, 2 in the TDF-FTC group (incidence, 0.91 per 100 person-years) and 14 in the placebo group (incidence, 6.60 per 100 person-years), a relative reduction in the TDF-FTC group of 86% (95% confidence interval, 40 to 98; P=0.002). Participants took a median of 15 pills of TDF-FTC or placebo per month (P=0.57). The rates of serious adverse events were similar in the two study groups. In the TDF-FTC group, as compared with the placebo group, there were higher rates of gastrointestinal adverse events (14% vs. 5%, P=0.002) and renal adverse events (18% vs. 10%, P=0.03). CONCLUSIONS: The use of TDF-FTC before and after sexual activity provided protection against HIV-1 infection in men who have sex with men. The treatment was associated with increased rates of gastrointestinal and renal adverse events. (Funded by the National Agency of Research on AIDS and Viral Hepatitis [ANRS] and others; ClinicalTrials.gov number, NCT01473472.).
Asunto(s)
Emtricitabina/uso terapéutico , Infecciones por VIH/prevención & control , VIH-1 , Homosexualidad Masculina , Profilaxis Pre-Exposición , Tenofovir/uso terapéutico , Adulto , Condones/estadística & datos numéricos , Método Doble Ciego , Quimioterapia Combinada , Emtricitabina/efectos adversos , Humanos , Estimación de Kaplan-Meier , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Factores de Riesgo , Conducta Sexual , Enfermedades de Transmisión Sexual/epidemiología , Tenofovir/efectos adversosRESUMEN
BACKGROUND: Robotic nipple-sparing mastectomy (RNSM) could be a significant advancement in the treatment of breast cancers and prophylaxis because the mastectomy is performed without leaving any scar on the breast. The aim of this study was to assess the feasibility and the safety of RNSM with immediate prosthetic breast reconstruction (IPBR). METHODS: In this prospective study, RNSM with IPBR was offered to patients with breast cup size A, B or C and ptosis grade ≤ 2. In case of oncologic surgery, RNSM was proposed only if the tumor was located more than 2 cm away from the nipple-areola complex (NAC) and if postoperative radiation was not indicated. In case of prophylactic surgery, RNSM was proposed only if a high-risk genetic mutation had been identified. The primary endpoint was the rate of skin or NAC necrosis. The rate of conversion to open technique, the duration of the procedure, and postoperative complications were also analyzed. RESULTS: Sixty-three RNSM with IPBR were performed in 33 patients. There were no cases of mastectomy skin flap or NAC necrosis. We had to convert to an open technique in one case (1.6%). Three infections occurred (4.8%), one leading to implant loss (1.6%). No other major complications were observed. CONCLUSIONS: Preliminary data attest to the feasibility, the reproducibility, and the safety of this approach. However, long-term data are needed to confirm the oncological safety and the esthetic stability of the result. Trial registration identifier NCT02673268.