Kidney regeneration and repair after transplantation

PURPOSE OF REVIEW: To briefly show which are the mechanisms and cell types involved in kidney regeneration and describe some of the therapies currently under study in regenerative medicine for kidney transplantation. RECENT FINDINGS: The kidney contains cell progenitors that under specific circumstances have the ability to regenerate specific structures. Apart from the knowledge gained in the self-regenerative properties of the kidney, new concepts in regenerative medicine such as organ engineering and the use of mesenchymal stem cell-based therapies are currently the focus of attention in the field. SUMMARY: Overall, kidney regeneration is a reality and the knowledge on how to control it will be one of the main scopes in the present and future

Massive Parallel Current Power Amplifier Concept for Power Hardware in the Loop Applications

The development of the smartgrid increases the complexity of the current electric grid. To verify and validate the operation of the systems involved in it, Power Hardware-In-theLoop (PHIL) technique allows to test the complete system in an exhaustive way. But the reduced bandwidth of the overall test system can cause inaccuracies and instabilities, which can be harmful for the Hardware Under Test (HUT) or the people who are performing the test. To increase PHIL performance and tackle these problems, this paper proposes a new concept of high bandwidth current amplifier. It is based on a topology of massive parallel interleaved buck-boost converter, which distribute in an equal manner the total current in all the branches. This current reduction allows to use transistors with better switching behaviour, which increase the bandwidth of the converter. Furthermore, a Discontinuous Conduction Mode (DCM) is used, obtaining the nominal output current in only one switching cycle. Description of the concept and the design parameters are provided. Finally, the behaviour of the proposed Power Amplifier (PA) at high frequency setpoint currents is shown in a Matlab/Simulink simulation. © 2022, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved

La Cantalera: an exceptional window onto the vertebrate biodiversity of the Hauterivian-Barremian transition in the Iberian Peninsula.

La Cantalera is an accumulation site for fossil vertebrates consisting mainly of teeth and isolated postcranial remains. It has the greatest vertebrate biodiversity of any site from the Hauterivian-Barremian transition in the Iberian Peninsula. Up to now, 31 vertebrate taxa have been recognized: an osteichthyan (Teleostei indet.), two amphibians (Albanerpetonidae indet. and Discoglossidae indet.), a chelonian (Pleurosternidae? indet.), a lizard (Paramacellodidae? indet.), four crocodylomorphs (cf. Theriosuchus sp., Bernissartiidae indet., Goniopholididae indet., cf. Lisboasaurus sp.), two pterosaurs (Istiodactylidae? indet., Ornithocheiridae? indet.), four ornithopod dinosaurs (Iguanodontoidea indet., Hadrosauroidea? indet., “Hypsilophodontidae” indet., Rhabdodontidae? indet.), a thyreophoran (Polacanthidae indet.), a sauropod (Euhelopodidae indet.), eleven theropods (Carcharodontosauridae? indet., Baryonychinae indet., aff. Paronychodon sp., Maniraptora indet. 1-3, Dromaeosaurinae indet. 1-3, Velociraptorinae indet., Avialae? indet.) and three or four multituberculate mammals (Cantalera abadi, Eobaatar sp., Plagiaulacidae or Eobaataridae gen. et sp. indet., “Plagiaulacida” indet.). Nine ootaxa have also been distinguished at the site of La Cantalera. Oofamilies assigned to dinosaurs (Elongaloolithidae, Prismatoolithidae, cf. Spheroolithidae), to crocodiles (Krokolithidae) and eggshells of two oofamilies incertidae sedis are represented. This association is consistent with the record of bone and tooth remains from the site. La Cantalera was formed in a marshy environment where there was an intermittent body of water. The great majority of the vertebrate fossil remains lack evidence of transport, so the preserved association is a good representation of the vertebrate ecosystem in or around the marshy area of La Cantalera. The vertebrate association of La Cantalera displays certain differences with respect to those from lacustrine environments of the Hauterivian-Barremian transition of the Iberian Range. These differences include, for example, the absence of Chondrichthyes, the merely token presence of the osteichthyans, the scarcity of chelonians, the presence of exclusively multituberculate mammals, the lower diversity of sauropods and the greater diversity of theropods

Infective endocarditis in dogs in the UK: 77 cases (2009-2019).

ObjectivesTo determine the causative organisms, clinical features and outcome of canine infective endocarditis in the UK.Materials and methodsMedical records of three veterinary referral hospitals were searched for dogs with infective endocarditis between December 2009 and December 2019. Signalment, clinical signs, causative organism, valve affected, treatment and survival data were recorded.ResultsSeventy-seven cases with possible or definite infective endocarditis (according to the modified Duke criteria) were included. The majority were large breed (40/77 - 51.9%). There were 47 of 77 (61%) male dogs and the mean age was 7.3 ±3 years. A causative organism was identified in 26 of 77 (33.8%) cases. The most common organisms were Escherichia coli (7/27 - 25.9%), Pasteurella spp. (5/27 - 18.5%), Staphylococcus spp. (4/27 - 14.8%) and Corynebacterium spp. (4/27 - 14.8%). Bartonella spp. were not detected in any patients. The mitral valve was most commonly affected (48/77 - 62.3%). Clinical features were non-specific, with lethargy being the most common clinical sign observed (53/77 - 68.8%). Fifty-three dogs (68.8%) survived to discharge. The median survival time post discharge was 425 days (2 to 3650 days). The development of congestive heart failure was associated with a poorer outcome. Cardiac troponin concentration, antithrombotic use and the development of thromboembolism or arrhythmias were not significantly associated with outcome.Clinical significanceSome dogs with infective endocarditis that survive to discharge can have a long lifespan. The inability to detect an underlying organism is common and Bartonella spp. may be a less prevalent cause of canine infective endocarditis in the UK than in the USA

Kidney Transplantation Group of the Spanish Society of Nephrology

Document publicat també en castellàThe Board of Directors of the Spanish Society of Nephrology (S.E.N.) approved at its ordinary meeting of 18 December 2012 the creation of a Transplantation Working Group (SENTRA). In accordance with the Regulations of the S.E.N. Working Groups, in promoting the establishment of a working group, four priority aspects must be addressed..

Galectin-3 shapes toxic alpha-synuclein strains in Parkinson's disease.

Parkinson's Disease (PD) is a neurodegenerative and progressive disorder characterised by intracytoplasmic inclusions called Lewy bodies (LB) and degeneration of dopaminergic neurons in the substantia nigra (SN). Aggregated α-synuclein (αSYN) is known to be the main component of the LB. It has also been reported to interact with several proteins and organelles. Galectin-3 (GAL3) is known to have a detrimental function in neurodegenerative diseases. It is a galactose-binding protein without known catalytic activity and is expressed mainly by activated microglial cells in the central nervous system (CNS). GAL3 has been previously found in the outer layer of the LB in post-mortem brains. However, the role of GAL3 in PD is yet to be elucidated. In post-mortem samples, we identified an association between GAL3 and LB in all the PD subjects studied. GAL3 was linked to less αSYN in the LB outer layer and other αSYN deposits, including pale bodies. GAL3 was also associated with disrupted lysosomes. In vitro studies demonstrate that exogenous recombinant Gal3 is internalised by neuronal cell lines and primary neurons where it interacts with endogenous αSyn fibrils. In addition, aggregation experiments show that Gal3 affects spatial propagation and the stability of pre-formed αSyn fibrils resulting in short, amorphous toxic strains. To further investigate these observations in vivo, we take advantage of WT and Gal3KO mice subjected to intranigral injection of adenovirus overexpressing human αSyn as a PD model. In line with our in vitro studies, under these conditions, genetic deletion of GAL3 leads to increased intracellular αSyn accumulation within dopaminergic neurons and remarkably preserved dopaminergic integrity and motor function. Overall, our data suggest a prominent role for GAL3 in the aggregation process of αSYN and LB formation, leading to the production of short species to the detriment of larger strains which triggers neuronal degeneration in a mouse model of PD

Cellular Immunity to Predict the Risk of Cytomegalovirus Infection in Kidney Transplantation: A Prospective, Interventional, Multicenter Clinical Trial

Background: Improving cytomegalovirus (CMV) immune-risk stratification in kidney transplantation is highly needed to establish guided preventive strategies. Methods: This prospective, interventional, multicenter clinical trial assessed the value of monitoring pretransplant CMV-specific cell-mediated immunity (CMI) using an interferon-γrelease assay to predict CMV infection in kidney transplantation. One hundred sixty donor/recipient CMV-seropositive (D+/R+) patients, stratified by their baseline CMV (immediate-early protein 1)-specific CMI risk, were randomized to receive either preemptive or 3-month antiviral prophylaxis. Also, 15-day posttransplant CMI risk stratification and CMI specific to the 65 kDa phosphoprotein (pp65) CMV antigen were investigated. Immunosuppression consisted of basiliximab, tacrolimus, mycophenolate mofetil, and corticosteroids in 80% of patients, whereas 20% received thymoglobulin induction therapy. Results: Patients at high risk for CMV based on pretransplant CMI developed significantly higher CMV infection rates than those deemed to be at low risk with both preemptive (73.3% vs 44.4%; odds ratio [OR], 3.44 [95% confidence interval {CI}, 1.30-9.08]) and prophylaxis (33.3% vs 4.1%; OR, 11.75 [95% CI, 2.31-59.71]) approaches. The predictive capacity for CMV-specific CMI was only found in basiliximab-treated patients for both preemptive and prophylaxis therapy. Fifteen-day CMI risk stratification better predicted CMV infection (81.3% vs 9.1%; OR, 43.33 [95% CI, 7.89-237.96]). Conclusions: Pretransplant CMV-specific CMI identifies D+/R+ kidney recipients at high risk of developing CMV infection if not receiving T-cell-depleting antibodies. Monitoring CMV-specific CMI soon after transplantation further defines the CMV infection prediction risk. Monitoring CMV-specific CMI may guide decision making regarding the type of CMV preventive strategy in kidney transplantation. Clinical Trials Registration: NCT02550639

Fundamental Parameters of He-Weak and He-Strong Stars

We carried out low resolution spectroscopic observations in the wavelength range 3400-4700 A of 20 He-weak and 8 He-strong stars to determine their fundamental parameters by means of the Divan-Chalonge-Barbier (BCD) spectrophotometric system. For a few He-weak stars we also estimate the effective temperatures and the angular diameters by integrating absolute fluxes observed over a wide spectral range. Non-LTE model calculations are carried out to study the influence of the He/H abundance ratio on the emergent radiation of He-strong stars and on their Teff determination. We find that the effective temperatures, surface gravities and bolometric absolute magnitudes of He-weak stars estimated with the BCD system and the integrated flux method are in good agreement between each other, and they also agree with previous determinations based on several different methods. The mean discrepancy between the visual absolute magnitudes derived using the Hipparcos parallaxes and the BCD values is on average 0.3 mag for He-weak stars, while it is 0.5 mag for He-strong stars. For He-strong stars, we note that the BCD calibration, based on stars in the solar environment, leads to overestimated values of Teff. By means of model atmosphere calculations with enhanced He/H abundance ratios we show that larger He/H ratios produce smaller BD which naturally explains the Teff overestimation. We take advantage of these calculations to introduce a method to estimate the He/H abundance ratio in He-strong stars. The BD of HD 37479 suggests that the Teff of this star remains fairly constant as the star spectrum undergoes changes in the intensity of H and He absorption lines. Data for the He-strong star HD 66765 are reported for the first time.Comment: Accepted for publication in A&

Magnetoestratigrafía del Cretácico Superior del sector Occidental de las Sierras Exteriores (Pirineo Occidental); implicaciones bioestratigráficas.

El Cretácico Superior del sector más Occidental de las Sierras Exteriores (Sa de Sto. Domingo) está escasamente representado en potencia pero presenta las facies más someras y transicionales donde se han recuperado recientemente restos de vertebrados fósiles (Osteichthyes, Chondrichthyes y Dinosauria), algunos de los cuales son de carácter continental. En este trabajo se presentan los resultados del análisis magnetoestratigráfico llevado a cabo en 4 secciones de pequeña potencia situadas entre los meridianos de San Felices y de Luesia (Prov. de Zaragoza). La magnetización característica de estas rocas es estable, primaria y muestra dos polaridades del campo magnético. La correlación tentativa entre perfiles, unida al conocimiento de las asociaciones de vertebrados existente en la cuenca de Graus-Tremp, permiten proponer una correlación preliminar que relacionaría los niveles fosilíferos con el cron C32n (Campaniense) y las facies Garum con los crones C29r, C29n y C28r (Maastrichtiense y Daniense) de la escala global de polaridad magnética. Esta correlación conlleva un hiato sedimentario durante el Maastrichtiense que deberá ser revisado en futuros estudios sedimentológicos

History Shaped the Geographic Distribution of Genomic Admixture on the Island of Puerto Rico

Contemporary genetic variation among Latin Americans human groups reflects population migrations shaped by complex historical, social and economic factors. Consequently, admixture patterns may vary by geographic regions ranging from countries to neighborhoods. We examined the geographic variation of admixture across the island of Puerto Rico and the degree to which it could be explained by historic and social events. We analyzed a census-based sample of 642 Puerto Rican individuals that were genotyped for 93 ancestry informative markers (AIMs) to estimate African, European and Native American ancestry. Socioeconomic status (SES) data and geographic location were obtained for each individual. There was significant geographic variation of ancestry across the island. In particular, African ancestry demonstrated a decreasing East to West gradient that was partially explained by historical factors linked to the colonial sugar plantation system. SES also demonstrated a parallel decreasing cline from East to West. However, at a local level, SES and African ancestry were negatively correlated. European ancestry was strongly negatively correlated with African ancestry and therefore showed patterns complementary to African ancestry. By contrast, Native American ancestry showed little variation across the island and across individuals and appears to have played little social role historically. The observed geographic distributions of SES and genetic variation relate to historical social events and mating patterns, and have substantial implications for the design of studies in the recently admixed Puerto Rican population. More generally, our results demonstrate the importance of incorporating social and geographic data with genetics when studying contemporary admixed populations