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Estimating carbon stocks in wooded systems is crucial to quantify national greenhouse gas balance estimates. However, inaccurate estimates are likely due to the divergent architecture of many species. The monkey puzzle tree Araucaria araucana, with its umbrella-like architecture is a vivid example. This species, often found in monodominant stands at high elevations, is the greatest carbon reservoir in the landscape, hence estimating its carbon storage is crucial. To provide the necessary basis for these estimations, we documented the variation in basic density and moisture content along the stem profile, identified the most suitable biomass estimation models, and quantified biomass allocation for three age ranges. We measured, felled, weighed, and separated trees into three categories: stem wood, stem bark, and foliage (branches + scaly leaves). The log-linear form of the simple allometric equation Y = aXb, based on diameter at breast height as the explanatory variable, covered a large part of the variation and showed good cross-validation performance (>0.96). Models using more covariates achieved lower absolute errors, but the estimation of the additional model parameters was associated with greater uncertainty. A multi-objective model comparison revealed that the best additional covariate to further improve biomass estimation was total tree height. The mean absolute percentage error was 9.8% for the total aboveground biomass, 8% for stem wood, 12% for stem bark and 24% for foliage. Changes in biomass distribution among tree components were related to age. For older trees, there was a relative increase in stem wood, a decreased proportion of foliage, but no change in stem bark. The proportion of stem bark biomass is similar to that of Araucaria angustifolia, but higher than in other conifers and most trees in general. Our results provide key properties for A. araucana and general guidance for the selection of easily-measurable variables allowing for excellent predictive power for local biomass estimation. [ABSTRACT FROM AUTHOR]

Abstract: Background: High‐risk acute leukemia (AL) and myelodysplastic syndrome (MDS) remain a therapeutic challenge. Unmanipulated haploidentical‐related donor transplantation based on a myeloablative conditioning regimen (HAPLO‐MAC) and post‐transplant cyclophosphamide (PT‐Cy) as prophylaxis against graft vs host disease (GvHD) is now a promising rescue strategy that could become universally available. Objective: To evaluate the results of HAPLO‐MAC with PT‐Cy in patients with AL and MDS reported to the Haploidentical Transplantation Subcommittee of the Spanish Group for Hematopoietic Transplantation (GETH). Patients and methods: We report our multicenter experience using an IV busulfan‐based HAPLO‐MAC regimen and PT‐Cy for treatment of 65 adults with high‐risk AL and MDS. Results: Engraftment was recorded in 64 patients (98.5%), with a median time to neutrophil and platelet recovery of 16 and 27 days, respectively. The cumulative incidence of grade II‐IV acute GvHD and chronic GvHD was 28.6% and 27.5%, respectively. After a median follow‐up of 31 months for survivors, the cumulative incidence of non‐relapse mortality and relapse at 2 years was 18.8% and 25%, respectively. Estimated 30‐month event‐free survival and overall survival were 56% and 54.5%, respectively. Conclusion: HAPLO‐MAC comprising an IV busulfan‐based conditioning regimen enabled long‐term disease control with acceptable toxicity in high‐risk AL and MDS. [ABSTRACT FROM AUTHOR]

• The serial sections are easy to manipulate as a whole and artifact-free. • Suitable to study the interphase prostheses-tissues. • To cut areas with different hardness without causing splintering or wrinkling. • The avoidance of grinding saves most of the original piece. • Useful for stereo, light and electron microscopes. The histological study of hard pieces such as tendons and calcified lesions and tissues is a field that has been gaining increased attention owing to the rapid development of implantable prostheses, among other factors. In these studies, serial sectioning is utilized to detect areas of interest throughout the entire piece, as it enables the application of the appropriate light and electron microscopy techniques in these areas. We propose the "three-sectioning method" that subjects the pieces to three consecutive cycles of embedding and sectioning to localize and study the areas of interest, as an efficient technique for these histological studies. The pieces were first embedded in epoxy resin and then cut into thick sections (approximately 300 μm) for the first cycle. Next, areas of interest selected on these thick sections were re-embedded in epoxy resin to be sectioned again (second sectioning) to obtain a series of semithin sections (1–3 μm). These semithin sections are usually studied using the most relevant techniques for light microscopy. Smaller areas of interest are selected to be cut into ultrathin sections (60–90 nm) for transmission electron microscopy. If necessary, the selected areas of the semithin sections can be embedded again, and then cut into new ultrathin sections. The different kinds of sections we have described here may also be studied using scanning electron microscopy. This systematic method facilitates correlative microscopy from lower to higher magnifications along with the usage of a broad variety of histological techniques including electron microscopy. [ABSTRACT FROM AUTHOR]

Background: iPSC (induced pluripotent stem cells) banks of iPSC lines with homozygous HLA (human leukocyte antigen) haplotypes (haplobanks) are proposed as an affordable and off-the-shelf approach to allogeneic transplantation of iPSC derived cell therapies. Cord blood banks offer an extensive source of HLA-typed cells suitable for reprogramming to iPSC. Several initiatives worldwide have been undertaken to create national and international iPSC haplobanks that match a significant part of a population. Methods: To create an iPSC haplobank that serves the Spanish population (IPS-PANIA), we have searched the Spanish Bone Marrow Donor Registry (REDMO) to identify the most frequently estimated haplotypes. From the top ten donors identified, we estimated the population coverage using the criteria of zero mismatches in HLA-A, HLA-B, and HLA-DRB1 with different stringencies: high resolution, low resolution, and beneficial mismatch. Results: We have calculated that ten cord blood units from homozygous donors stored at the Spanish cord blood banks can provide HLA-A, HLA-B, and HLA-DRB1 matching for 28.23% of the population. Conclusion: We confirm the feasibility of using banked cord blood units to create an iPSC haplobank that will cover a significant percentage of the Spanish and international population for future advanced therapy replacement strategies. [ABSTRACT FROM AUTHOR]

This is a retrospective cohort study of consecutive adult patients who received a haploidentical-SCT (haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) in a single centre. Poor graft function (PGF) was defined as the occurrence of either persistent neutropenia (ANC < 0.5 × 109/µL) with poor response to granulocyte colony-stimulating factors (G-CSF) and/or thrombocytopenia (platelets < 20 × 109/L) with transfusion dependence, with complete donor chimerism and without concurrent severe GVHD or underlying disease relapse, during the first 12 months after transplantation. Forty-four (27.5%) out of 161 patients were diagnosed with PGF. Previous CMV reactivation was significantly more frequent in patients with PGF (88.6% versus 73.5%, p = 0.04) and the number of reactivations was also higher in these patients. Besides, early CMV reactivations in the first 6 months post-SCT were also significantly more frequent among patients with PGF (88.6% versus 71.8% p = 0.025). Thirty-two percent of patients with PGF were treated with increasing doses of thrombopoietin-receptor agonists (TRA) and 7 patients were treated with a donor CD34 + selected boost. In total, 93.2% of patients reached adequate peripheral blood counts in a median time of 101 days (range 11–475) after diagnosis. PGF is a frequent complication after haplo-SCT with PT-Cy. CMV reactivation might be the most relevant factor associated to its development. Even when most patients recover peripheral counts with support therapy, there is a group of patients with persistent cytopenias who can effectively be treated with TRA and/or a boost of CD34 + selective cells. [ABSTRACT FROM AUTHOR]

Summary: We conducted a phase 2 trial to evaluate the safety and efficacy of bendamustine instead of BCNU (carmustine) in the BEAM (BCNU, etoposide, cytarabine and melphalan) regimen (BendaEAM) as conditioning for autologous stem‐cell transplantation (ASCT) in patients with aggressive lymphomas. The primary endpoint was 3‐year progression‐free survival (PFS). Sixty patients (median age 55 [28–71] years) were included. All patients (except one who died early) engrafted after a median of 11 (9–72) and 14 (4–53) days to achieve neutrophil and platelet counts of >0.5 × 109/l and >20 × 109/l, respectively. Non‐relapse mortality at 100 days and 1 year were 3.3% and 6.7%, respectively. With a median follow‐up of 67 (40–77) months, the estimated 3‐year PFS and overall survival (OS) were 58% and 75%, respectively. Patients in partial response at study entry had significantly worse PFS and OS than patients who underwent ASCT in complete metabolic remission, and this was the only prognostic factor associated with both PFS (Relative risk [RR], 0.27 [95% confidence interval {CI} [0.12–0.56]) and OS (RR, 0.40 [95% CI 0.17–0.97]) in the multivariate analysis. BendaEAM conditioning is therefore a feasible and effective regimen in patients with aggressive lymphomas. However, patients not in complete metabolic remission at the time of transplant had poorer survival and so should be considered for alternative treatment strategies. [ABSTRACT FROM AUTHOR]

Development of de novo hematologic malignancies in donor cells after allogeneic stem cell transplantation (allo-SCT) provides a useful in vivo model to study the process of leukemogenesis. A systematic analysis of the cases reported in the literature was performed to identify risk factors and mechanisms involved in the pathogenesis of donor cell–derived hematologic neoplasms (DCHN) and leukemogenic transformation. Relevant data were extracted from 137 cases. Cases of DCHN show a wide heterogeneity with regard to recipient/donor age, sex mismatch, and conditioning regimen. Some characteristics, such as the type of primary disease, the type of hematologic malignancy of the DCHN, and the stem cell source used in the transplant procedure, differ from those expected. Mechanisms involved in the pathogenesis of DCHN are complex, and several hypotheses have been proposed, such as pre-existing hematologic neoplasms or premalignant clones in the donor, decreased immune surveillance, and damage to bone marrow microenvironment in the recipient. Most likely several if not all these mechanisms play a role in DCHN development. Novel approaches, such as next-generation sequencing to study consecutive samples after allo-SCT in these patients, appear to be promising to decipher the mechanisms of leukemogenesis. [ABSTRACT FROM AUTHOR]

Background: Development of de novo alloantibodies against recipient's red blood cell (RBC) antigens by engrafted donor's lymphocytes is a known phenomenon in the setting of allogeneic hematopoietic stem cell transplantation (HSCT). This situation is usually clinically insignificant. We report a case of early clinically relevant hemolytic anemia in a blood group A1 D+ patient, due to a limited production of anti-D and anti-A1 produced by nonpreviously sensitized newly engrafted donor's immune system.Case Report: A 31-year-old Caucasian woman, blood group A1 , D+, with Hodgkin's lymphoma, received an unmanipulated haploidentical allogeneic peripheral blood HSCT after a nonmyeloablative conditioning regimen. Donor blood group was A2 B, D-. The patient had an uneventful course until Day +34, when she developed clinically significant hemolytic anemia with a positive direct antiglobulin test. Anti-D and anti-A1 produced by the donor-engrafted lymphocytes were detected both in serum and in eluate. The hemolysis produced an accelerated group change, turning the patient's ABO group into A2 B 2 weeks after the detection of the alloantibodies. As the residual patient's RBCs progressively disappeared, anti-D and anti-A1 production decreased and were not detected in serum by Day +41.Conclusion: This case illustrates that de novo alloantibody production against ABO and D antigens by the newly engrafted donor's lymphocytes can occasionally cause clinically significant anemia. To our knowledge, this is the first case reported of clinically significant hemolytic anemia due to a transient anti-D anti-A1 alloimmunization after T-cell-repleted haploidentical HSCT. [ABSTRACT FROM AUTHOR]

We designed a phase II clinical trial including Y-90 ibritumomab-tiuxetan as part of a reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (AlloSCT) in high-risk non-Hodgkin lymphoma (Clinical Trials Identifier: NCT00644371). Eligible patients had high-risk relapsed/refractory aggressive lymphoma. The conditioning regimen consisted of rituximab 250 mg (days −21 and −14), Y-90 ibritumomab IV (.4 m Ci/kg, day −14), fludarabine 30 mg/m 2 i.v. (days −3 and −2) plus melphalan 70 mg/m 2 i.v. (days −3 and −2) or 1 dose of melphalan and thiotepa 5 mg/kg (day −8). Donors were related. Eighteen patients were evaluable. At the time of transplantation, responses were complete remission (CR) (n = 7, 39%), partial remission (n = 6, 33%) or refractory disease (n = 4, 28%). Y-90-ibritumomab infusions were well tolerated, with no adverse reactions. Nonrelapse mortality at 1 year was 28%. Median follow-up was 46 (range, 39 to 55) months. Estimated 1-year progression-free survival (PFS) was 50%, and 4-year overall survival (OS) and PFS were both 44.4%. CR at the moment of AlloSCT had significant impact on PFS (71% versus 27%, P  = .046) and OS (71% versus 27%, P  = .047). Our results show that Y-90-ibritumomab-tiuxetan as a component of RIC for AlloSCT is feasible in patients with high-risk B cell lymphoma. Development of phase III clinical trials is needed to clarify the contribution of radioimmunotherapy to RIC AlloSCT. [ABSTRACT FROM AUTHOR]

Alloreactivity triggered by interaction between killer cell immunoglobulin-like receptors ( KIRs) and natural killer ( NK) cells plays a role in the graft-versus-tumor effect after hematopoietic stem cell transplantation ( SCT). Our aim in this study was to evaluate this role in the setting of T-cell-repleted haploidentical SCT with postinfusion high-dose cyclophosphamide ( PT-Cy). We included 33 patients. Among patient-donor pairs with at least 1 inhibitory KIR ( iKIR) gene mismatch, event-free survival ( EFS) and cumulative incidence of relapse 1 year after transplant were significantly better (85% vs. 37% [ P = 0.008] and 18% vs. 46% [ P = 0.041], respectively). A subanalysis in 12 patients with Hodgkin's lymphoma ( HL) showed an improvement in EFS 1 year after transplant in those patients with KIR ligand mismatch (100% vs. 25%, P = 0.012), although overall survival ( OS) was not affected (85% vs. 80%, P = 0.2). Eight of 12 patient-donors pairs presented iKIR mismatches. Of note, this outcome was better in the small subgroup, both for EFS (100% vs. 25%, P = 0.012) and for OS (100% vs. 37%, P = 0.004). Our data suggest that in the setting of T-cell-repleted haploidentical SCT with PT-Cy, iKIR mismatch is associated with improved survival, with particularly good results for both iKIR and KIR ligand mismatches in patients with HL. [ABSTRACT FROM AUTHOR]

We report the outcome of 30 consecutive patients with Hodgkin disease ( HD) who underwent single-unit UCBT. Most (90%) patients had failed previous autologous hematopoietic stem cell transplantation. The conditioning regimens were based on combinations of thiotepa, busulfan, cyclophosphamide or fludarabine, and antithymocyte globulin. The cumulative incidence ( CI) of myeloid engraftment was 90% [95% confidence interval (C.I.), 74-98%] with a median of 18 d (range, 10-48). CI of acute graft-versus-host disease (Gv HD) grades II- IV was 30% (95% C.I., 17-44%), while the incidence of chronic GVHD was 42% (95% C.I., 23-77%). The non-relapse mortality ( NRM) at 100 d and 4 yr was 30% (95% C.I., 13-46%) and 47% (95% C.I., 29-65%), respectively. EBV-related post-transplant lymphoproliferative disease ( EBV- PTLD) accounted for more than one-third of transplant-related death, with an estimate incidence of 26% (95% C.I., 9-44). The incidence of relapse at 4 yr was 25% (95% C.I., 9-42%). Four-year event-free survival ( EFS) and overall survival ( OS) were 28% and 30%, respectively. Despite a high NRM and an unexpected high incidence of EBV- PTLD, UCBT in heavily pretreated HD patients is an option for patients lacking a suitable adult donor, provided the disease is not in refractory relapse. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) following solid organ or hematologic malignancy (secondary ALL, s-ALL) is not well characterized. We analyzed the characteristics and outcome of patients with s-ALL and compared them with those of patients with de novo- ALL. Of 448 patients, 24 (5%) had previous neoplasia. Sixteen patients had received previous cytotoxic therapy (therapy-associated ALL, t-ALL), and eight had not (antecedent-malignancy ALL, am-ALL). Except for more advanced age in patients with s-ALL, no statistically significant differences were observed in WBC count, CNS involvement, immunophenotype or cytogenetics between the groups, nor in complete remission (t-ALL: 94%; am-ALL: 75%; de novo-ALL: 85%), 3-year remission duration (58%; 50%; 72%), overall survival (71%; 38%; 60%) or event-free survival (53%, 38%; 53%). Our study did not show poor clinical or cytogenetic features or inferior outcome in ALL patients with antecedent neoplastic disease, irrespective of the type of treatment received for the neoplasia. [ABSTRACT FROM AUTHOR]

The FOXP3 gene encodes for a protein (Foxp3) involved in the development and functional activity of regulatory T cells (CD4+/CD25+/Foxp3+), which exert regulatory and suppressive roles over the immune system. After allogeneic stem cell transplantation, regulatory T cells are known to mitigate graft versus host disease while probably maintaining a graft versus leukemia effect. Short alleles (≤(GT)15) for the (GT)n polymorphism in the promoter/enhancer of FOXP3 are associated with a higher expression of FOXP3, and hypothetically with an increase of regulatory T cell activity. This polymorphism has been related to the development of auto- or alloimmune conditions including type 1 diabetes or graft rejection in renal transplant recipients. However, its impact in the allo-transplant setting has not been analyzed. In the present study, which includes 252 myeloablative HLA-identical allo-transplants, multivariate analysis revealed a lower incidence of grade III-IV acute graft versus host disease (GVHD) in patients transplanted from donors harboring short alleles (OR = 0.26, CI 0.08–0.82, p = 0.021); without affecting chronic GVHD or graft versus leukemia effect, since cumulative incidence of relapse, event free survival and overall survival rates are similar in both groups of patients. [ABSTRACT FROM AUTHOR]

We report a lung-invasive fungal disease with possible cutaneous needle tract seeding in a patient with a febrile neutropenia caused by the Basidiomycetes mold Inonotus spp. Although rare, Inonotus spp. should be added to the list of microorganisms causing invasive fungal disease in neutropenic patients with hematologic malignancies. [ABSTRACT FROM AUTHOR]

Strategies for reversing graft failure (GF) after allogeneic stem cell transplant (SCT) depend on the options available in each situation. GF was reported in 16 Spanish institutions from January 2006 to July 2011. Primary GF was defined as an absolute neutrophil count (ANC) > 0.5 × 109/L not reached by day + 28 after SCT from peripheral blood (PB) or bone marrow (BM) progenitors and by day + 42 after SCT from unrelated cord blood (UCB) progenitors. Secondary GF was defined as a recurrent ANC < 0.5 × 109/L. Eighty-nine patients with GF were reported, and 80 patients received a second SCT. The 5-year survival probability was 31% (95% confidence interval [CI]: 18-44%), and the incidences of non-relapse mortality and relapse estimated by competing risks were 47% (95% CI: 36-58%) and 21% (95% CI: 4-28%). The strategy adopted to treat GF was heterogeneous, and no approach could be unequivocally recommended for this situation. The prognosis of patients with GF was poor even after successful recovery from GF. [ABSTRACT FROM AUTHOR]

Among the strategies to optimize engraftment of cord blood (CB) stem cell transplantation (SCT), single CB with the coinfusion of CD34 + stem cells from an HLA-mismatched auxiliary donor (haplo-cord) provides a valid alternative for adult patients without a suitable donor. A total of 132 high-risk adult patients with hematological malignancies from 3 Spanish institutions underwent myeloablative haplo-cord SCT. The median age was 37 years and median weight was 70 kg; 37% had active disease. The median number of postprocessing CB total nucleated and CD34 + cells was 2.4 × 10 7 /kg (interquartile range [IQR], 1.8 to 2.9) and 1.4 × 10 5 /kg (IQR, .9 to 2), respectively. Neutrophil engraftment occurred in a median of 11.5 days (IQR, 10.5 to 16.5) and platelet engraftment at 36 days (IQR, 25.5 to 77). Graft failure was 2% overall and only 9% for CB. Cumulative incidence of acute graft-versus-host disease (GHVD) grades II to IV was 21% and cumulative incidence of chronic GVHD was 21%. Median follow-up was 60 months (range, 3.5 to 163). Overall survival was 43.5%, event-free survival was 38.3%, nonrelapse mortality was 35%, and relapse was 20% at 5 years. Myeloablative haplo-cord SCT results in fast engraftment of neutrophils and platelets, low incidences of acute and chronic GVHD, and favorable long-term outcomes using single CB units with relatively low cell content. Moreover, CB cell dose had no impact on CB engraftment and survival in this study. Therefore, haplo-cord SCT expands donor availability while reducing CB cell dose requirements. [ABSTRACT FROM AUTHOR]

Allogeneic stem cell transplantation (allo- SCT) has become the treatment of choice in patients with intermediate-risk and high-risk acute myeloid leukemia ( AML). The quality of response to treatment, assessed in terms of detection of minimal residual disease ( MRD), has been consistently associated with prognosis and clinical outcome in patients with AML. The aim of the present study was to evaluate the prognostic impact of analyzing MRD in bone marrow using 4-color multiparametric flow cytometry ( MFC) in 29 patients with AML before and after allo- SCT. Eighteen patients who were shown to be MRD-negative [≤0.1% leukemia-associated immunophenotypes ( LAIPs)] by MFC at transplantation and underwent allo- SCT had lower rates of relapse (15% vs. 66%, P = 0.045), better overall 1-yr survival (83% vs. 52%, P = 0.021) and a lower cumulative incidence of relapse ( P = 0.032) than patients who were MRD-positive (>0.1%). All post-transplant MRD-positive patients underwent a therapeutic intervention after transplant (tapering of immunosuppression, donor lymphocyte infusion, or re-transplant) with the intention of preventing relapse. Disease was controlled and MRD disappeared in five of these patients. Disease recurred in the other seven patients. We can conclude that follow-up with MFC for the detection of MRD in AML before and after SCT is useful for predicting relapse. In the post-transplant setting, monitoring of MRD by MFC could be a key preemptive intervention. [ABSTRACT FROM AUTHOR]

Abstract: Matched unrelated donor (MUD) transplantation is the first alternative in the absence of a matched sibling donor. For patients without a suitable adult donor, we have adopted the dual stem cell transplantation protocol consisting of cord blood (CB) in combination with CD34+ cells from a third party HLA-mismatched donor. We analyzed the outcomes of patients undergoing both procedures in a single center. Starting in 2004, a total of 20 patients with high-risk disease underwent 22 dual transplants and 25 patients underwent myeloablative MUD transplantation. The 30-day cumulative incidence of neutrophil engraftment was similar in both groups (91% and 95%), with a median time to engraftment of 14 and 16 days, respectively. Grade II-IV acute graft-versus-host disease was more frequent in the MUD group (40% versus 5%). Except for a tendency toward a higher incidence of viral hemorrhagic cystitis in the dual transplantation group, posttransplantation infectious events were comparable in the 2 groups. The 3-year cumulative incidence rates of relapse (41% versus 44%) and nonrelapse mortality (30% versus 25%) were similar in the MUD and dual transplantation cohorts. Estimated 3-year overall survival and disease-free survival were 47% and 41%, respectively, with no survival advantage for either group. In our experience, dual transplantation offers survival rates comparable to those from myeloablative MUD transplantation with similar nonrelapse mortality rates. [Copyright &y& Elsevier]

Relapse remains the main cause of treatment failure in patients with acute myelogeous leukemia (AML) after allogeneic hemopoietic stem cell transplantation (SCT). The Wilms’ tumor 1 gene (WT1) is reportedly overexpressed in >90% of patients with AML and thus can be useful for minimal residual disease (MRD) monitoring. The aim of this study was to evaluate the usefulness of WT1 expression as a relapse predictor marker in patients with AML after SCT and compare it with flow cytometry (FC) and chimerism studies. WT1 expression was assessed retrospectively using quantitative RT-PCR in bone marrow and peripheral blood from 21 patients. Patients were classified according to WT1 dynamics posttransplantation. Eleven of the 21 patients had low and stable WT1 levels. All of these 11 patients showed complete chimerism and negative MRD by FC and remained in complete remission with a median follow-up of 27 months (range, 18-98 months). In contrast, 10 of 21 patients showed WT1 overexpression after SCT, and 9 of these 10 patients relapsed. The incidence of relapse differed significantly between the 2 groups of patients according to WT1 expression post-SCT (P = .00003). Relapse in the 9 patients occurred at a median of 314 days (range, 50-560 days). Interestingly, in these patients, relapse was first predicted by WT1 (with negative FC and complete chimerism) in 7 patients. WT1 overexpression was correlated with disease burden in patients with AML before and after allogeneic SCT. In patients who relapsed, both medullary and extramedullary relapse were better anticipated by WT1 overexpression compared with FC and chimerism. [ABSTRACT FROM AUTHOR]

Summary: Flood peak data for focus catchments in Costa Rica, Ecuador, Chile and Argentina are analyzed to test the hypothesis that, as the size of the hydrological event increases, the effect of forest cover on the peak discharge becomes less important. Previous research suggests that this hypothesis may hold for small catchments (less than 1km2) but the pattern is less clear for large catchments. The principal study results are for small paired catchments (0.6–10km2) with different forest covers (forest/pasture) in highland Ecuador and a small (0.35km2) plantation catchment in southern Chile subjected to logging. The former were analyzed by comparing the corresponding peak discharges for given rainfall events, the latter by comparing the relationships between peak discharge and rainfall event size for the pre- and post-logging periods. In all cases there is relative or absolute convergence of the responses as discharge increases, with convergence likely for flood return periods of around 10years. More limited data for larger catchments which have undergone either deforestation or afforestation (131km2 in Costa Rica and 94–1545km2 in Chile) suggest that the percentage change in forest cover must exceed 20–30% to provoke a measurable response in peak discharge; convergence of peak discharge response at high flows (return periods of around 5years) for the different forest covers may then be observed. For a 12.9-km2 snowmelt-affected catchment in Tierra del Fuego, Argentina, extreme floods require rain-on-snow events but the data are not sufficient to quantify the complex relationship between forest cover, event return period and peak discharge. In general, forest cover is unlikely to reduce, significantly, peak discharges generated by extreme rainfall but may still offer substantial mitigation benefits for moderate (i.e. more frequent) rainfall events. [ABSTRACT FROM AUTHOR]

Abstract: Background: Pandemic 2009 influenza A/H1N1 (H1N1v) is resistant to adamantanes, leaving neuraminidase inhibitors as the only therapeutic option. Other mutations are considered to be associated with virulence and clinical severity. However, out of the surveillance programs, few studies analyze the presence of resistance/virulent H1N1v variants in certain clinical circumstances. Objectives: To define the frequency and role of resistance and virulence mutations in a specific clinical circumstance—in patients with persistent infection by H1N1v. Study design: Observational study of patients with persistent H1N1v infection admitted to our hospital. Results: NAI-resistance mutations were detected in 14.3% of cases with persistent infection (2/14), and in none of the non-persistent controls (0/15). These cases were initially infected with susceptible variants that acquired resistance at different time-points after therapy with oseltamivir (OTV). The first case (case 2) was an HIV-positive patient who rapidly acquired resistance 9 days after diagnosis (6 days on OTV) and whose infection resolved after standard OTV therapy. The second case (case 3) was a patient with acute myeloid leukemia and the longest viral persistence (59 days). The resistance mutation was detected in the specimen taken on day 37 after diagnosis (30 days on OTV). Once the resistance mutation was identified, OTV was substituted by zanamivir and the infection resolved. In addition to mutations encoding resistance, variants associated with virulence were also sought. The D225G mutation was not found in any case, whereas the D225E variant was identified in three persistent cases but also in two non-persistent ones. In one patient, the D225E substitution coincided with the H275 resistant mutation. Conclusions: NAI-resistance mutations were detected, at rather different paces, in non-severe immunosuppressed cases with persistent infection by influenza A/H1N1v. [ABSTRACT FROM AUTHOR]

Objective, Methods, and Results. To reduce the period of posttransplant neutropenia and related early morbidity and mortality of cord blood (CB) transplants, we assessed the feasibility of co-infusion of a low number of highly purified peripheral blood CD34+ cells from a related haploidentical donor with a CB graft. Between March 1999 and May 2002, 11 patients with high-risk hematologic malignancies were transplanted using this strategy. The seven patients who received a haploidentical peripheral blood graft and a CB graft from a sibling (6) or the father (1) had prompt recovery (9–17 days, median 10) of the absolute neutrophil count (ANC) to greater than 0.5×109/L. Analysis of DNA polymorphisms showed initial predominance of the haploidentical genotype both in granulocytes and in mononuclear cells, and subsequent progressive replacement by cells of CB genotype until final complete CB chimerism was achieved by patients who survived for sufficient periods of time. The four patients who received maternal haploidentical cells had no significant contribution of these to blood leukocytes, although complete CB chimerism was achieved by three of them and two reached engraftment of the CB on days +20 and +36. Morbidity due to early bacterial or fungal infections was remarkably low in patients with prompt ANC recovery.Conclusion. Our data show that co-infusion of a CB unit and a low number of haploidentical CD34+ cells may result in a shortened period of posttransplant neutropenia. This is likely the result of prompt and transient engraftment of the haploidentical hematopoietic stem cells that may provide the patient antimicrobial protection until the later engraftment of the CBhematopoietic stem cells. [Copyright &y& Elsevier]

The inclusion of electrospun nanofiber veils was revealed as an effective method for enhancing the mechanical properties of fiber-reinforced epoxy resin composites. These veils will eventually allow the incorporation of nanomaterials not only for mechanical reinforcement but also in multifunctional applications. Therefore, this paper investigates the effect of electrospun nanofibrous veils made of polyamide 6 modified with TiO2 nanoparticles on the mechanical properties of a carbon-fiber/epoxy composite. The nanofibers were included in the carbon-fiber/epoxy composite as a single structure. The effect of positioning these veils in different composite positions was investigated. Compared to the reference, the use of unmodified and TiO2 modified veils increased the flexural stress at failure and the fracture toughness of composites. When TiO2 modified veils were incorporated, new antibacterial properties were achieved due to the photocatalytic properties of the veils, widening the application area of these composites. [ABSTRACT FROM AUTHOR]

Delamination and brittle matrix fracture have long since been the biggest problems in fibre-reinforced composites. Recently, the incorporation of electrospun nanofibre veils has been shown to be an effective method for improving the mechanical properties of these composites, without causing process problems and negatively affecting other mechanical properties. Thus, these nanofibres have the potential to be used as thickness-reinforcing materials in composites. This paper investigates the effect of incorporating standalone electrospun nanofibre veils made of two different types of polyamide 6 (PA6) on the mechanical properties of carbon fibre/epoxy composites. The influence of positioning the electrospun veils at different interlaminar positions of the laminate has also been investigated. [ABSTRACT FROM AUTHOR]

Chimerism dynamics in bone marrow, peripheral blood (PB), and T lymphocytes (TL) has been associated with the development of various complications after allogeneic stem-cell transplantation (allo-SCT). In the present study, the usefulness of chimerism monitoring in CD25 + -activated leukocytes (AL), together with that in bone marrow, PB, and TL, for the anticipation of complications after allo-SCT, has been analyzed in 68 patients. In AL, we observed a slower dynamics toward complete chimerism (CC) than in PB ( p = 0.042), while no significant differences were found between TL and PB ( p = 0.12). Complete chimerism achievement in AL at day +30 has shown to be an independent risk factor for the development of grade II–IV acute graft-versus-host disease (aGvHD; hazard ratio [95% confidence interval]: 11.9 [1.5–91.7]; p = 0.017). Moreover, among patients achieving CC in TL and AL at different time-points after SCT ( n = 17/68), the incidence of grade II–IV aGvHD was significantly higher in patients who achieved CC earlier in AL (5/5) than in those who achieved CC earlier in TL (1/11; p = 0.001). Therefore, achievement of early complete donor chimerism in CD25 + AL is a strong predictor for the development of aGvHD. Prospective analysis of chimerism in AL could improve the post-SCT management of immunosuppressive therapy in transplanted patients. [ABSTRACT FROM AUTHOR]