Dyskeratosis congenita: natural history of the disease through the study of a cohort of patients diagnosed in childhood.

Background: Dyskeratosis congenita (DC) is a multisystem and ultra-rare hereditary disease characterized by somatic involvement, bone marrow failure, and predisposition to cancer. The main objective of this study is to describe the natural history of DC through a cohort of patients diagnosed in childhood and followed up for a long period of time. Material and methods: Multicenter, retrospective, longitudinal study conducted in patients followed up to 24 years since being diagnosed in childhood (between 1998 and 2020). Results: Fourteen patients were diagnosed with DC between the ages of 3 and 17 years (median, 8.5 years). They all had hematologic manifestations at diagnosis, and nine developed mucocutaneous manifestations during the first decade of life. Seven presented severe DC variants. All developed non-hematologic manifestations during follow-up. Mutations were identified in 12 patients. Thirteen progressed to bone marrow failure at a median age of 8 years [range, 3-18 years], and eight received a hematopoietic stem cell transplant. Median follow-up time was 9 years [range, 2-24 years]. Six patients died, the median age was 13 years [range, 6-24 years]. As of November 2022, eight patients were still alive, with a median age of 18 years [range, 6-32 years]. None of them have developed myeloblastic syndrome or cancer. Conclusions: DC was associated with high morbidity and mortality in our series. Hematologic manifestations appeared early and consistently. Non-hematologic manifestations developed progressively. No patient developed cancer possibly due to their young age. Due to the complexity of the disease multidisciplinary follow-up and adequate transition to adult care are essential.

Anthropogenic eutrophication of Lake Titicaca (Bolivia) revealed by carbon and nitrogen stable isotopes fingerprinting.

Cultural eutrophication is the leading cause of water quality degradation worldwide. The traditional monitoring of eutrophication is time-consuming and not integrative in space and time. Here, we examined the use of carbon (δ13C) and nitrogen (δ15N) isotopic composition to track the degree of eutrophication in a bay of Lake Titicaca impacted by anthropogenic (urban, industrial and agricultural wastewater) discharges. Our results show increasing δ13C and decreasing δ15N signatures in macrophytes and suspended particulate matter with distance to the wastewater source. In contrast to δ15N and δ13C signatures, in-between aquatic plants distributed along the slope were not only affected by anthropogenic discharges but also by the pathway of carbon uptake, i.e., atmospheric (emerged) vs aquatic (submerged). A binary mixing model elaborated from pristine and anthropogenic isotope end-members allowed the assessment of anthropogenically derived C and N incorporation in macrophytes with distance to the source. Higher anthropogenic contribution was observed during the wet season, attributed to enhanced wastewater discharges and leaching of agricultural areas. For both seasons, eutrophication was however found naturally attenuated within 6 to 8 km from the wastewater source. Here, we confirm that carbon and nitrogen stable isotopes are simple, integrative and time-saving tools to evaluate the degree of eutrophication (seasonally or annually) in anthropogenically impacted aquatic ecosystems.

Post-hematopoietic stem cell transplant squamous cell carcinoma in patients with Fanconi anemia: a dreadful enemy.

INTRODUCTION: Hematopoietic stem cell transplantation (HSCT) is a curative option for patients with Fanconi anemia (FA) and hematological manifestations but it does not prevent solid tumors, especially squamous cell carcinomas (SCC). METHODS: Retrospective study in 22 FA patients who had received HSCT and had been followed up beyond 2 years after HSCT. RESULTS: The median follow-up was 15 years. Six patients developed head-and-neck SCC after transplantation. The cumulative incidence of SCC at 15 and 30 years from the HSCT was 14.2% and 71.2%, respectively. One patient was diagnosed in stage IV and the rest, who were being followed up in cancer screening programs, in stage I. Treatment of SCC consisted of surgery in all patients; radiotherapy and chemotherapy were used in two patients and were poorly tolerated. CONCLUSION: FA patients have high risk of head-and-neck SCC. Multi-disciplinary programs for early cancer detection are of special relevance in these patients.

Survival and toxicity outcomes of hematopoietic stem cell transplantation for pediatric patients with Fanconi anemia: a unified multicentric national study from the Spanish Working Group for Bone Marrow Transplantation in Children.

Hematopoietic stem cell transplantation (HSCT) is currently the only curative option for hematological manifestations in patients with Fanconi anemia (FA). We report the outcome of 34 patients with FA inside a collaborative multicenter national study based on recommendations of Spanish Working Group for Bone Marrow Transplantation in Children (GETMON) between 2009 and 2016. Fludarabine-based conditioning regimen was carried out in all patients, with low dose total body irradiation in unrelated transplants. Disease status before HSCT was bone marrow failure (BMF) in 30 patients and myelodysplastic syndrome (MDS) in four. Donors were matched siblings donors (MSD) in 18, matched unrelated donors (MUD) in 15, and one haploidentical donor. All except one patient engrafted. Cumulative incidence of grades II-IV acute graft-versus-host disease (GVHD) was 29% and 11% for chronic GVHD. Median follow-up after HSCT was 6.5 years. Seven patients (21%) died due to transplant-related causes, two (6%) because of MDS relapse, and one (3%) after a squamous cell carcinoma. Overall survival (OS) was 73% at 5 years post-transplant, with no differences between MSD and MUD transplants. OS for patients with BMF was 80% while for MDS was 25%. Our data suggest HSCT can cure hematologic manifestations of most FA patients with BMF.

Diagenetic production, accumulation and sediment-water exchanges of methylmercury in contrasted sediment facies of Lake Titicaca (Bolivia).

Monomethylmercury (MMHg) concentrations in aquatic biota from Lake Titicaca are elevated although the mercury (Hg) contamination level of the lake is low. The contribution of sediments to the lake MMHg pool remained however unclear. In this work, seven cores representative of the contrasted sediments and aquatic ecotopes of Lake Titicaca were sliced and analyzed for Hg and redox-sensitive elements (Mn, Fe, N and S) speciation in pore-water (PW) and sediment to document early diagenetic processes responsible for MMHg production and accumulation in PW during organic matter (OM) oxidation. The highest MMHg concentrations (up to 12.2 ng L-1 and 90% of THg) were found in subsurface PWs of the carbonate-rich sediments which cover 75% of the small basin and 20% of the large one. In other sediment facies, the larger content of OM restricted MMHg production and accumulation in PW by sequestering Hg in the solid phase and potentially also by decreasing its bioavailability in the PW. Diagenetically reduced S and Fe played a dual role either favoring or restricting the availability of Hg for biomethylation. The calculation of theoretical diffusive fluxes suggests that Lake Titicaca bottom sediments are a net source of MMHg, accounting for more than one third of the daily MMHg accumulated in the water column of the Lago Menor. We suggest that in the context of rising anthropogenic pressure, the enhancement of eutrophication in high altitude Altiplano lakes may increase these MMHg effluxes into the water column and favor its accumulation in water and biota.

Determination of the nonradiative conversion efficiency of lead mixed-halide perovskites using optical and photothermal spectroscopy.

Mixed-halide organic-inorganic hybrid perovskites are considered promising light-absorbing materials in the development of solar cells related to the obtained high-power conversion efficiency. Current efforts are focused on the study of the energy-conversion mechanisms, where the nonradiative recombination pathway is the least explored. In this work, a combination of optical and photoacoustic spectroscopies is used to determine the visible spectral light-into-heat conversion efficiency of lead-based mixed-halide organic-inorganic hybrid perovskites in a semicomplete n-i-p mesoscopic perovskite solar cell (PSC). A remarkable average conversion efficiency of about 87% has been found for the nonradiative combination in the perovskite, with the estimated composition ${{\rm FA}_{0.71}}{{\rm MA}_{0.29}}{{\rm PbI}_{2.9}}{{\rm Br}_{0.1}}$FA0.71MA0.29PbI2.9Br0.1 in the wavelength range of 400 to 800 nm. As a result, 13% of the incident light is transformed in radiative recombination processes and/or photodegradation of the material. Furthermore, the extinction coefficient and refractive index of the material are reported, and it was found that the optical constants and the optical absorption in the short-wavelength range are significantly smaller than previously reported for${{\rm MAPbI}_3}$MAPbI3.

Measurement of the hysteretic thermal properties of W-doped and undoped nanocrystalline powders of VO2.

Hysteresis loops exhibited by the thermal properties of undoped and 0.8 at.% W-doped nanocrystalline powders of VO2 synthesized by means of the solution combustion method and compacted in pellets, are experimentally measured by photothermal radiometry. It is shown that: (i) the W doping reduces both the hysteresis loops of VO2 and its transition temperature up to 15 °C. (ii) The thermal diffusivity decreases (increases) until (after) the metallic domains become dominant in the VO2 insulating matrix, such that its variation across the metal-insulation transition is enhanced by 23.5% with W-0.8 at.% doping. By contrast, thermal conductivity (thermal effusivity) increases up to 45% (40%) as the metallic phase emerges in the VO2 structure due to the insulator-to-metal transition, and it enhances up to 11% (25%) in the insulator state when the local rutile phase is induced by the tungsten doping. (iii) The characteristic peak of the VO2 specific heat capacity is observed in both heating and cooling processes, such that the phase transition of the 0.8 at.% W-doped sample requires about 24% less thermal energy than the undoped one. (iv) The impact of the W doping on the four above-mentioned thermal properties of VO2 mainly shows up in its insulator phase, as a result of the distortion of the local lattice induced by the electrons of tungsten. W doping at 0.8 at.% thus enhances the VO2 capability to transport heat but diminishes its thermal switching efficiency.

ECLIM-SEHOP, a new platform to set up and develop international academic clinical trials for childhood cancer and blood disorders in Spain.

INTRODUCTION: Cancer and blood disorders in children are rare. The progressive improvement in survival over the last decades largely relies on the development of international academic clinical trials that gather the sufficient number of patients globally to elaborate solid conclusions and drive changes in clinical practice. The participation of Spain into large international academic trials has traditionally lagged behind of other European countries, mainly due to the burden of administrative tasks to open new studies, lack of financial support and limited research infrastructure in our hospitals. METHODS: The objective of ECLIM-SEHOP platform (Ensayos Clínicos Internacionales Multicéntricos-SEHOP) is to overcome these difficulties and position Spain among the European countries leading the advances in cancer and blood disorders, facilitate the access of our patients to novel diagnostic and therapeutic approaches and, most importantly, continue to improve survival and reducing long-term sequelae. ECLIM-SEHOP provides to the Spanish clinical investigators with the necessary infrastructural support to open and implement academic clinical trials and registries. RESULTS: In less than 3 years from its inception, the platform has provided support to 20 clinical trials and 8 observational studies, including 8 trials and 4 observational studies where the platform performs all trial-related tasks (integral support: trial setup, monitoring, etc.) with more than 150 patients recruited since 2017 to these studies. In this manuscript, we provide baseline metrics for academic clinical trial performance that permit future comparisons. CONCLUSIONS: ECLIM-SEHOP facilitates Spanish children and adolescents diagnosed with cancer and blood disorders to access state-of-the-art diagnostic and therapeutic strategies.

Thermal hysteresis measurement of the VO2 emissivity and its application in thermal rectification.

Hysteresis loops in the emissivity of VO2 thin films grown on sapphire and silicon substrates by a pulsed laser deposition process are experimentally measured through the thermal-wave resonant cavity technique. Remarkable variations of about 43% are observed in the emissivity of both VO2 films, within their insulator-to-metal and metal-to-insulator transitions. It is shown that: i) The principal hysteresis width (maximum slope) in the VO2 emissivity of the VO2 + silicon sample is around 3 times higher (lower) than the corresponding one of the VO2 + sapphire sample. VO2 synthesized on silicon thus exhibits a wider principal hysteresis loop with slower MIT than VO2 on sapphire, as a result of the significant differences on the VO2 film microstructures induced by the silicon or sapphire substrates. ii) The hysteresis width along with the rate of change of the VO2 emissivity in a VO2 + substrate sample can be tuned with its secondary hysteresis loop. iii) VO2 samples can be used to build a radiative thermal diode able to operate with a rectification factor as high as 87%, when the temperature difference of its two terminals is around 17 °C. This record-breaking rectification constitutes the highest one reported in literature, for a relatively small temperature change of diode terminals.

Mercury contamination level and speciation inventory in Lakes Titicaca & Uru-Uru (Bolivia): Current status and future trends.

Aquatic ecosystems of the Bolivian Altiplano (∼3800 m a.s.l.) are characterized by extreme hydro-climatic constrains (e.g., high UV-radiations and low oxygen) and are under the pressure of increasing anthropogenic activities, unregulated mining, agricultural and urban development. We report here a complete inventory of mercury (Hg) levels and speciation in the water column, atmosphere, sediment and key sentinel organisms (i.e., plankton, fish and birds) of two endorheic Lakes of the same watershed differing with respect to their size, eutrophication and contamination levels. Total Hg (THg) and monomethylmercury (MMHg) concentrations in filtered water and sediment of Lake Titicaca are in the lowest range of reported levels in other large lakes worldwide. Downstream, Hg levels are 3-10 times higher in the shallow eutrophic Lake Uru-Uru than in Lake Titicaca due to high Hg inputs from the surrounding mining region. High percentages of MMHg were found in the filtered and unfiltered water rising up from <1 to ∼50% THg from the oligo/hetero-trophic Lake Titicaca to the eutrophic Lake Uru-Uru. Such high %MMHg is explained by a high in situ MMHg production in relation to the sulfate rich substrate, the low oxygen levels of the water column, and the stabilization of MMHg due to abundant ligands present in these alkaline waters. Differences in MMHg concentrations in water and sediments compartments between Lake Titicaca and Uru-Uru were found to mirror the offset in MMHg levels that also exist in their respective food webs. This suggests that in situ MMHg baseline production is likely the main factor controlling MMHg levels in fish species consumed by the local population. Finally, the increase of anthropogenic pressure in Lake Titicaca may probably enhance eutrophication processes which favor MMHg production and thus accumulation in water and biota.

Landscape of early clinical trials for childhood and adolescence cancer in Spain.

PURPOSE: Despite numerous advances, survival remains dismal for children and adolescents with poor prognosis cancers or those who relapse or are refractory to first line treatment. There is, therefore, a major unmet need for new drugs. Recent advances in the knowledge of molecular tumor biology open the door to more adapted therapies according to individual alterations. Promising results in the adult anticancer drug development have not yet been translated into clinical practice. We report the activity in early pediatric oncology trials in Spain. METHODS: All members of the Spanish Society of Pediatric Hematology Oncology (SEHOP) were contacted to obtain information about early trials open in each center. RESULTS: 22 phase I and II trials were open as of May 2015: 15 for solid tumors (68 %) and 7 for hematological malignancies (32 %). Fourteen (64 %) were industry sponsored. Since 2010, four centers have joined the Innovative Therapies For Children With Cancer, an international consortium whose aim is developing novel therapies for pediatric cancers. A substantial number of studies have opened in these 5 years, improving the portfolio of trials for children. Results of recently closed trials show the contribution of Spanish investigators, the introduction of molecularly targeted agents and their benefits. CONCLUSIONS: Clinical trials are the way to evaluate new drugs, avoiding the use of off-label drugs that carry significant risks. The Spanish pediatric oncology community through the SEHOP is committed to develop and participate in collaborative academic trials, to favor the advancement and optimization of existing therapies in pediatric cancer.

Recommendations on hematopoietic stem cell transplantation for inherited bone marrow failure syndromes.

Allogeneic hematopoietic stem cell transplantation (HSCT) offers the potential to cure patients with an inherited bone marrow failure syndrome (IBMFS). However, the procedure involves the risk of treatment-related mortality and may be associated with significant early and late morbidity. For these reasons, the benefits should be carefully weighed against the risks. IBMFS are rare, whereas case reports and small series in the literature illustrate highly heterogeneous practices in terms of indications for HSCT, timing, stem cell source and conditioning regimens. A consensus meeting was therefore held in Vienna in September 2012 on behalf of the European Group for Blood and Marrow Transplantation to discuss HSCT in the setting of IBMFS. This report summarizes the recommendations from this expert panel, including indications for HSCT, timing, stem cell source and conditioning regimen.

[Survival analysis of hematopoietic stem cell transplantation in children with primary immunodeficiency in Spain]. / Análisis de la supervivencia de los niños con inmunodeficiencias primarias que han recibido un trasplante de progenitores hematopoyéticos en España.

INTRODUCTION: Children with primary immunodeficiency have severe life-threatening infections and a higher prevalence of autoimmune problems, allergy and lymphoproliferative disorders. Allogenic hematopoietic stem cell transplantation has been the only potentially curative option. PATIENTS AND METHODS: Patients with primary immunodeficiency underwent allogenic stem cell transplantation in the period 1985-2011, and registered in the Spanish Working Party for Bone Marrow Transplantation in Children. RESULTS: One hundred and fifty nine patients underwent 173 allogenic stem cell transplantations, of whom 97 had severe combined immunodeficiency, 30 with immune dysregulation disorders, 25 Wiskott-Aldrich syndrome, and 21 phagocyte disorders. The median patient age at diagnosis was 6 months (range: 17 days - 168 months) and the median patient age at transplant was 12 months (range: 1 month - 189 months). The donors were 30 (19%) identical siblings, 40 (25%) alternative family donors, and 89 (56%) unrelated donors. The source of stem cells was bone marrow in 68 (43%), cord blood in 52 (33%), and peripheral blood in 39 (24%). Ninety eight (61.6%) are alive, 57 (35.9%) died. Event-free survival at 10 years was 63%, with 90% for children transplanted from identical siblings, 36% for those transplanted from alternative family donors, and 66% for those transplanted from unrelated donors. CONCLUSIONS: The best results have been obtained with identical siblings, but other options may be considered.

Long-term outcome and prognostic factors of unrelated cord blood transplantation in children with haematological malignancies: a retrospective study using the Spanish Working Party for BMT in Children (GETMON) database.

Outcomes of unrelated cord blood transplants (UCBT) were assessed in 172 consecutive children, median age 5 years (range: 0.5-18), with haematological malignancies treated at nine Spanish hospitals between February 1996 and April 2009. Data were collected from the Spanish Working Party for Blood and Marrow Transplantation in Children (GETMON) database. ALL was diagnosed in 125 patients, AML in 43 and myelodysplastic syndrome in 4. Myeloid engraftment (ANC⩾0.5 × 10(9)/L) occurred in 87.2% at a median of 22 days and was associated with the total nucleated cell (TNC) dose infused and use of a TT-containing conditioning regimen. Cumulative incidence of relapse was 20% at 1 year post transplant and 29% at 3 years, being higher in patients with a diagnosis of ALL, very high risk disease and GVHD grades 0-1. Cumulative incidence of non-relapse mortality (NRM) was 19% at 100 days post transplant and 39% at 1 year. BU-FLU-TT-ATG-conditioned patients had lower NRM. Disease-free survival (DFS) was 40% at 2 years post transplant (for patients transplanted since 2006). On multivariate analysis, TNC dose infused, AML and BU-FLU-TT-ATG-conditioning regimen increased the probability of DFS. It is of paramount importance to select cord blood units with the highest cell dose. As the BU-FLU-TT-ATG-conditioning regimen was associated with better DFS owing to lower NRM, further prospective studies testing this regimen are warranted.

Impact of HLA mismatch direction on outcomes after umbilical cord blood transplantation for hematological malignant disorders: a retrospective Eurocord-EBMT analysis.

HLA matching is a critical determinant of outcomes for patients who have undergone umbilical cord blood transplantation (UCBT). Data have been published on the importance of donor/recipient HLA mismatch direction on UCBT outcomes. HLA mismatch in the graft-versus-host (GVH) direction is defined as a donor homozygous at an HLA locus, while the recipient shares one HLA Ag with the donor. HLA mismatch in the host-versus-graft (HVG) direction is defined as a recipient homozygous with the donor sharing one HLA Ag. In our study we focused on confirming, using an independent population, whether transplantation outcomes would be different when HLA mismatch direction was considered. We analyzed 1565 patients who received a single-unit UCBT for malignant disease. Median age was 15 years and 72% of patients were transplanted for leukemia. In multivariate analysis, using the 5/6 HLA-matched population as reference, one or two HLA mismatches in the GVH or HVG direction were not associated with non-relapse related mortality and survival. On the basis of our results, there is no evidence to support a change in the current practice for cord blood unit selection.

[Results of hematopoietic stem cell transplantation in hemoglobinopathies: thalassemia major and sickle cell disease]. / Resultados del trasplante de progenitores hematopoyéticos en hemoglobinopatías: talasemia maior y enfermedad drepanocítica.

BACKGROUND: The prevalence of hemoglobinopathies in Spain is increasing as a result of immigration. Thalassemia major presents with chronic hemolytic anemia that requires regular red blood cell transfusions within the first year of life. Patients with sickle cell disease suffer from chronic anemia, vasculopathy and progressive damage in almost any organ. There is decreased life expectancy in both conditions. Allogeneic hematopoietic stem cell transplantation represents the only potentially curative option. PATIENTS: Seventeen patients (fourteen thalassemia major, and three sickle cell disease) underwent allogeneic hematopoietic stem cell transplantations. RESULTS: In the thalassemia group, nine donors were HLA-geno-identical siblings, two were partially matched related donors (one HLA allele mismatch), and three unrelated donors. All three patients with sickle cell disease were transplanted from HLA-geno-identical siblings. The source of stem cells was bone marrow in sixteen cases. Median patient age at transplant was six years (range: 1-16) in the thalassemia group, and twelve years (range: 8-15) in the sickle cell disease group. The graft was successful in all patients. Secondary graft rejection was observed in two thalassemia patients rendering them dependent on blood transfusions. Complete chimerism was observed in thirteen patients and, although mixed chimerism occurred in two, with all of them showing normal hemoglobin levels after transplantation and not requiring further transfusion support. Patients affected by sickle cell disease did not present with new vaso-occlusive crises, and stabilization of pulmonary and neurological function was observed. Chronic graft-versus-host disease was detected in three patients affected by thalassemia, and hypogonadotrophic hypogonadism in five patients. CONCLUSIONS: We conclude that for thalassemia major and sickle cell disease, allogenic hematopoietic stem cell transplantation from HLA-geno-identical siblings offers a high probability of complication-free survival. Despite good results, morbidity and mortality associated with transplantation from unrelated donors is a risk that might be considered, in contrast to a non-curative medical treatment that offers a long term survival. For thalassemia major groups it could be an option, but not for sickle cell disease, which is still in the investigational phase.

Impact of pretransplant minimal residual disease after cord blood transplantation for childhood acute lymphoblastic leukemia in remission: an Eurocord, PDWP-EBMT analysis.

To address the prognostic value of minimal residual disease (MRD) before unrelated cord blood transplantation (UCBT) in children with acute lymphoblastic leukemia (ALL), we analyzed 170 ALL children transplanted in complete remission (CR) after myeloablative conditioning regimen. In all, 72 (43%) were in first CR (CR1), 77 (45%) in second CR (CR2) and 21 (12%) in third CR (CR3). The median interval from MRD quantification to UCBT was 18 days. All patients received single-unit UCBT. Median follow-up was 4 years. Cumulative incidence (CI) of day-60 neutrophil engraftment was 85%. CI of 4 years relapse was 30%, incidence being lower in patients with negative MRD before UCBT (hazard ratio (HR)=0.4, P=0.01) and for those transplanted in CR1 and CR2 (HR=0.3, P=0.002). Probability of 4 years leukemia-free survival (LFS) was 44%, (56, 44 and 14% for patients transplanted in CR1, CR2 and CR3, respectively (P=0.0001)). Patients with negative MRD before UCBT had better LFS after UCBT compared with those with positive MRD (54% vs 29%; HR=2, P=0.003). MRD assessment before UCBT for children with ALL in remission allows identifying patients at higher risk of relapse after transplantation. Approaches that may decrease relapse incidence in children given UCBT with positive MRD should be investigated to improve final outcomes.