In vivo cell reprogramming to pluripotency: generating induced pluripotent stem cells in situ for tissue regeneration

Artificially induced changes of cell identity are increasingly attracting attention as potential strategies to regenerate diseased or injured tissues, but still rely heavily on ex vivo culture with the exception of a small number of in vivo transdifferentiation studies. The reprogramming of somatic cells to pluripotency in vivo is even less explored, partly due to fears of teratoma formation. In this thesis, we hypothesised that such twist in cell fate can be safely achieved in vivo provided that sufficient but transient levels of reprogramming factors are locally expressed. We also speculated that transiently pluripotent cells can be generated in different tissues, thanks to the universality of the Yamanaka reprogramming factors, and that they may contribute to replenish the injured site after an insult. In vivo induction of pluripotency was first described in the liver and later in the skeletal muscle of wild-type mice. In both scenarios, the fast but transient upregulation of pluripotency markers and downregulation of tissue-specific genes did not progress to teratoma formation. The in vivo reprogrammed hepatocytes were established as a cell line in vitro, the so-called in vivo induced pluripotent stem (i2PS) cells, and their pluripotency was confirmed at the molecular and functional levels. Clusters of in vivo reprogrammed cells within the skeletal muscle tissue were found to express pluripotency and myogenic progenitor markers and to re-integrate in the normal tissue architecture after a transient proliferative stage recapitulating events of normal postnatal myogenesis. Finally, in vivo reprogramming to pluripotency resulted in a modest enhancement of regeneration and functional rehabilitation in a model of skeletal muscle injury. In conclusion, this work not only provides proof-of-concept of safe in vivo cell reprogramming to pluripotency but also presents a thorough characterisation of the in vivo reprogrammed cells and supports the potential of such strategy to improve regeneration after injury

Cost analysis of the management of brain metastases in patients with advanced ALK+ NSCLC: alectinib versus crizotinib

Aim: To estimate management cost of NSCLC ALK+ patients with and without brain metastasis (BM), and to compare annual costs in patients treated with alectinib or crizotinib. Methods: Management cost/year (euro 2018) in patients with and without BM was estimated with disaggregated resource consumption provided by local oncologists, including medical visits, hospitalizations, diagnostic/laboratory tests, imaging techniques and surgical procedures. The comparison of costs/year with alectinib and crizotinib, considered the cumulative 12-month incidence of BM in ALEX trial (9.4 and 41.4%, respectively). Results: Management cost was euro6173.42/patient-year without BM and euro21,637.50/patient-year with BM. With alectinib, average cost/patient was lower than crizotinib (euro4948.51/patient-year). Conclusion: Prevention of BM with alectinib may result in reductions of cost/year in the management of advanced ALK+ NSCLC

Glucose Oxidation to Pyruvate Is Not Essential for Brucella suis Biovar 5 Virulence in the Mouse Model

Brucella species cause brucellosis, a worldwide extended zoonosis. The brucellae are related to free-living and plant-associated alpha 2-Proteobacteria and, since they multiply within host cells, their metabolism probably reflects this adaptation. To investigate this, we used the rodent-associated Brucella suis biovar 5, which in contrast to the ruminant-associated Brucella abortus and Brucella melitensis and other B. suis biovars, is fast-growing and conserves the ancestral Entner-Doudoroff pathway (EDP) present in the plant-associated relatives. We constructed mutants in Edd (glucose-6-phosphate dehydratase; first EDP step), PpdK (pyruvate phosphate dikinase; phosphoenolpyruvate pyruvate), and Pyk (pyruvate kinase; phosphoenolpyruvate -> pyruvate). In a chemically defined medium with glucose as the only C source, the Edd mutant showed reduced growth rates and the triple Edd-PpdK-Pyk mutant did not grow. Moreover, the triple mutant was also unable to grow on ribose or xylose. Therefore, B. suis biovar 5 sugar catabolism proceeds through both the Pentose Phosphate shunt and EDP, and EDP absence and exclusive use of the shunt could explain at least in part the comparatively reduced growth rates of B. melitensis and B. abortus. The triple Edd-PpdK-Pyk mutant was not attenuated in mice. Thus, although an anabolic use is likely, this suggests that hexose/pentose catabolism to pyruvate is not essential for B. suis biovar 5 multiplication within host cells, a hypothesis consistent with the lack of classical glycolysis in all Brucella species and of EDP in B. melitensis and B. abortus. These results and those of previous works suggest that within cells, the brucellae use mostly 3 and 4 C substrates fed into anaplerotic pathways and only a limited supply of 5 and 6 C sugars, thus favoring the EDP loss observed in some species

Five-year follow-up mortality prognostic index for colorectal patients

Purpose: To identify 5-year survival prognostic variables in patients with colorectal cancer (CRC) and to propose a survival prognostic score that also takes into account changes over time in the patient's health-related quality of life (HRQoL) status. Methods: Prospective observational cohort study of CRC patients. We collected data from their diagnosis, intervention, and at 1, 2, 3, and 5 years following the index intervention, also collecting HRQoL data using the EuroQol-5D-5L (EQ-5D-5L), European Organization for Research and Treatment of Cancer's Quality of Life Questionnaire-Core 30 (EORTC-QLQ-C30), and Hospital Anxiety and Depression Scale (HADS) questionnaires. Multivariate Cox proportional models were used. Results: We found predictors of mortality over the 5-year follow-up to be being older; being male; having a higher TNM stage; having a higher lymph node ratio; having a result of CRC surgery classified as R1 or R2; invasion of neighboring organs; having a higher score on the Charlson comorbidity index; having an ASA IV; and having worse scores, worse quality of life, on the EORTC and EQ-5D questionnaires, as compared to those with higher scores in each of those questionnaires respectively. Conclusions: These results allow preventive and controlling measures to be established on long-term follow-up of these patients, based on a few easily measurable variables. Implications for cancer survivors: Patients with colorectal cancer should be monitored more closely depending on the severity of their disease and comorbidities as well as the perceived health-related quality of life, and preventive measures should be established to prevent adverse outcomes and therefore to ensure that better treatment is received. Trial registration: ClinicalTrials.gov identifier: NCT02488161Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was supported in part by grants from the Instituto de Salud Carlos III and the European Regional Development Fund (PS09/00314, PS09/00910, PS09/00746, PS09/00805, PI09/90460, PI09/90490, PI09/90453, PI09/90441, PI09/90397); the Spanish Ministry of the Economy (PID2020-115738 GB-I00); the Departments of Health (2010111098) and Education, Language Policy and Culture (IT1456-22; IT1598-22; IT-1187–19) of the Basque Government; the Research Committee of Galdakao Hospital; the REDISSEC (Red de Investigación en Servicios de Salud en Enfermedades Crónicas) thematic network of the Instituto de Salud Carlos III; and the Department of Education of the Basque Government through the Consolidated Research Group MATHMODE (IT1456-22) and the Basque Government through BMTF “Mathematical Modeling Applied to Health” Project

Combining statistical techniques to predict post-surgical risk of 1-year mortality for patients with colon cancer

Introduction: Colorectal cancer is one of the most frequently diagnosed malignancies and a common cause of cancer-related mortality. The aim of this study was to develop and validate a clinical predictive model for1-year mortality among patients with colon cancer who survive for at least 30 days after surgery. Methods: Patients diagnosed with colon cancer who had surgery for the first time and who survived 30 days after the surgery were selected prospectively. The outcome was mortality within 1 year. Random forest, genetic algorithms and classification and regression trees were combined in order to identify the variables and partition points that optimally classify patients by risk of mortality. The resulting decision tree was categorized into four risk categories. Split-sample and bootstrap validation were performed. Results: A total of 1945 patients were enrolled in the study. The variables identified as the main predictors of 1-year mortality were presence of residual tumour, ASA risk score, pathological tumour staging, Charlson comorbidity index, intraoperative complications, adjuvant chemotherapy and recurrence of tumour. The model was internally validated; the area under the curve (AUC) was 0.896 in the derivation sample and 0.835 in the validation sample. Risk categorization leads to AUC values of 0.875 and 0.832 in the derivation and validation samples, respectively. Optimal cut-off point of estimated risk had a sensitivity of 0.889 and a specificity of 0.758. Conclusions: The decision-tree was a simple, interpretable, valid and accurate prediction rule of 1-year mortality among colon cancer patients who survived for at least 30 days after surgery.Instituto de Salud Carlos III (PS09/00314, PS09/00910, PS09/00746, PS09/00805, PI09/90460, PI09/90490, PI09/90453, PI09/90441, PI09/90397 and the thematic networks REDISSEC - Red de Investigación en Servicios de Salud en Enfermedades Crónicas), co-funded by European Regional Development Fund/European Social Fund (ERDF/ESF "Investing in your future"); Research Committee of the Hospital Galdakao Department of Health and the Department of Education, Language Policy and Culture from the Basque Government (2010111098, IT620-13) MINECO and FEDER (MTM2013-40941-P, MTM2016-74931-P)

A ZZ Ceti white dwarf in SDSS J133941.11+484727.5

We present time-resolved spectroscopy and photometry of the cataclysmic variable (CV) SDSSJ133941.11+484727.5 (SDSS1339) which has been discovered in the Sloan Digital Sky Survey Data Release 4. The orbital period determined from radial velocity studies is 82.524(24)min, close to the observed period minimum. The optical spectrum of SDSS1339 is dominated to 90% by emission from the white dwarf. The spectrum can be successfully reproduced by a three-component model (white dwarf, disc, secondary) with Twd=12500K for a fixed log g=8.0, d=170pc, and a spectral type of the secondary later than M8. The mass transfer rate corresponding to the optical luminosity of the accretion disc is very low,~1.7x10^-13Msun/yr. Optical photometry reveals a coherent variability at 641s with an amplitude of 0.025mag, which we interpret as non-radial pulsations of the white dwarf. In addition, a long-period photometric variation with a period of either 320min or 344min and an amplitude of 0.025mag is detected, which bears no apparent relation with the orbital period of the system. Similar long-period photometric signals have been found in the CVs SDSSJ123813.73-033933.0, SDSSJ204817.85-061044.8, GW Lib and FS Aur, but so far no working model for this behaviour is available.Comment: MNRAS, in press, 8 pages, 10 figures, some figures downgraded to meet the file size constraint of arxiv.or

Association between an oxidative balance score and mortality: a prospective analysis in the SUN cohort

We aimed to prospectively investigate the association of an overall oxidative balance score (OBS) with all-cause death and cause-specifc mortality among participants in the Seguimiento Universidad de Navarra (SUN) Study, a Mediterranean cohort of Spanish graduates. Methods Using baseline information on 12 a priori selected dietary and non-dietary lifestyle pro- and antioxidants exposures—vitamins C and E, β-carotenes, selenium, zinc, heme iron, polyphenols, total antioxidant capacity, body mass index, alcohol, smoking, and physical activity—we constructed an equally weighted OBS categorized into quartiles, with higher scores representing greater antioxidant balance. Cox proportional hazards models were ftted to evaluate the association between the OBS and mortality. Results A total of 18,561 participants (mean [SD] age, 38.5 [12.4] years; 40.8% males) were included in the analysis. During a median follow-up of 12.2 years (interquartile range 8.3–14.9), 421 deaths were identifed, including 80 deaths from cardiovascular disease (CVD), 215 from cancer, and 126 from other causes. After adjustment for potential confounders, the hazard ratios and 95% confdence interval (CIs) between the highest quartile (predominance of antioxidants) vs. the lowest quartile (reference category) were 0.35 (95% CI 0.22–0.54, P-trend<0.001) for all-cause mortality, 0.18 (95% CI 0.06–0.51, P-trend=0.001) for CVD mortality, 0.35 (95% CI 0.19–0.65, P-trend=0.002) for cancer mortality, and 0.45 (95% CI 0.20–1.02, P-trend=0.054) for other-cause mortality. Conclusion Our fndings suggest a strong inverse association between the OBS and all-cause, CVD, and cancer mortality. Individuals exposed to both antioxidant dietary and lifestyle factors may potentially experience the lowest mortality riskOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. The SUN Project has received funding from the Spanish Government-Instituto de Salud Carlos III, and the European Regional Development Fund (FEDER) (RD 06/0045, CIBER-OBN, Grants PI10/02658, PI10/02293, PI13/00615, PI14/01668, PI14/01798, PI14/01764, PI17/01795, and G03/140), the Navarra Regional Government (27/2011, 45/2011, 122/2014), the Government Delegation for the National Drug Plan (2020/ 021) and the University of Navarra. Maria Soledad Hershey receives ERC traininggrant support (T42 OH008416

GATE : a simulation toolkit for PET and SPECT

Monte Carlo simulation is an essential tool in emission tomography that can assist in the design of new medical imaging devices, the optimization of acquisition protocols, and the development or assessment of image reconstruction algorithms and correction techniques. GATE, the Geant4 Application for Tomographic Emission, encapsulates the Geant4 libraries to achieve a modular, versatile, scripted simulation toolkit adapted to the field of nuclear medicine. In particular, GATE allows the description of time-dependent phenomena such as source or detector movement, and source decay kinetics. This feature makes it possible to simulate time curves under realistic acquisition conditions and to test dynamic reconstruction algorithms. A public release of GATE licensed under the GNU Lesser General Public License can be downloaded at the address http://www-lphe.epfl.ch/GATE/

Involvement of the TPR2 subdomain movement in the activities of ϕ29 DNA polymerase

The polymerization domain of ϕ29 DNA polymerase acquires a toroidal shape by means of an arch-like structure formed by the specific insertion TPR2 (Terminal Protein Region 2) and the thumb subdomain. TPR2 is connected to the fingers and palm subdomains through flexible regions, suggesting that it can undergo conformational changes. To examine whether such changes take place, we have constructed a ϕ29 DNA polymerase mutant able to form a disulfide bond between the apexes of TPR2 and thumb to limit the mobility of TPR2. Biochemical analysis of the mutant led us to conclude that TPR2 moves away from the thumb to allow the DNA polymerase to replicate circular ssDNA. Despite the fact that no TPR2 motion is needed to allow the polymerase to use the terminal protein (TP) as primer during the initiation of ϕ29 TP–DNA replication, the disulfide bond prevents the DNA polymerase from entering the elongation phase, suggesting that TPR2 movements are necessary to allow the TP priming domain to move out from the polymerase during transition from initiation to elongation. Furthermore, the TPR2-thumb bond does not affect the equilibrium between the polymerization and exonuclease activities, leading us to propose a primer-terminus transference model between both active sites

Emergence of Tuning to Natural Stimulus Statistics along the Central Auditory Pathway

We have previously shown that neurons in primary auditory cortex (A1) of anaesthetized (ketamine/medetomidine) ferrets respond more strongly and reliably to dynamic stimuli whose statistics follow "natural" 1/f dynamics than to stimuli exhibiting pitch and amplitude modulations that are faster (1/f(0.5)) or slower (1/f(2)) than 1/f. To investigate where along the central auditory pathway this 1/f-modulation tuning arises, we have now characterized responses of neurons in the central nucleus of the inferior colliculus (ICC) and the ventral division of the mediate geniculate nucleus of the thalamus (MGV) to 1/f(gamma) distributed stimuli with gamma varying between 0.5 and 2.8. We found that, while the great majority of neurons recorded from the ICC showed a strong preference for the most rapidly varying (1/f(0.5) distributed) stimuli, responses from MGV neurons did not exhibit marked or systematic preferences for any particular gamma exponent. Only in A1 did a majority of neurons respond with higher firing rates to stimuli in which gamma takes values near 1. These results indicate that 1/f tuning emerges at forebrain levels of the ascending auditory pathway