Ruin-of-the-rivers? A global review of run-of-the-river dams.

The classification of a hydropower scheme as run-of-the-river (or run-of-river; ROR) evokes an image of a low-impact installation; however, examination of eight case studies worldwide shows that substantial negative societal and ecological impacts are tied to them, albeit in somewhat different ways. We conclude that ROR dams not only potentially displace communities, disrupt livelihoods, and degrade environments in surrounding areas, but they also divert water from areas of need, impact aquatic ecology through habitat destruction and disruption of fish migrations, emit non-trivial amounts of greenhouse gases over the lifespan of the project, and disrupt streamflow in downstream river sections. While these negative impacts vary on a case-by-case basis, medium and large ROR dams consistently have multiple and cumulative impacts, even when not having appreciable reservoirs. We contend that many impactful dams do not qualify as low-impact ROR projects, despite being defined as such. Such mislabeling is facilitated in part by the ambiguous definition of the term, which risks the ROR concept being used by proponents of impactful structures to downplay their negative effects and thus mislead the public or gain status, including within the Clean Development Mechanism in relation to mitigating climate change.

Impact of run-of-river damming on increasing phytoplankton biomass and species shift in a large Amazonian river.

Run-of-river (ROR) dams, often perceived as having minimal environmental impact, can induce significant hydrodynamic changes that alter aquatic ecosystems. We investigated the impacts of an ROR dam on the Madeira River, the largest Amazon tributary, focusing on phytoplankton communities, their ecological implications, and related environmental factors. Our study examined changes in biomass and environmental factors (using General Linear Mixed Models - GLMM), species composition (using PERMANOVA) before and after damming, in both the main channel and tributaries (N = 549 samples). We also identified indicator species associated with different damming phases and regions through an indicator value analysis. The results showed that, following dam construction, the phytoplankton community changed in both the main channel and tributaries, with a shift from lotic diatoms to lentic phytoflagellates. This transition was likely facilitated by altered hydrodynamics and possibly influenced by the decomposition of flooded vegetation in the dam's influence zone. The decomposition of this vegetation could explain both the observed increase in oxygen consumption and the subsequent rise in phytoflagellate biomass after damming. However, despite the overall increase in phytoplankton biomass, the values remained within oligotrophic to mesotrophic conditions, consistent with the low nutrient concentrations recorded. However, we caution that the dam-created hydrodynamic conditions are optimal for phytoplankton growth, potentially exacerbating nutrient-related issues in the future. We recommend proactive management strategies to prevent nutrient enrichment from activities such as agriculture and livestock in isolated Amazon areas affected by dams, thereby mitigating potential degradation of water quality linked to increased phytoplankton biomass.

Effects of space and environment on phytoplankton distribution in subtropical reservoirs depend on functional features of the species.

Environmental factors and dispersal can influence the structure of biological communities. Their effects can depend on the functional features of the species in the community. Since species belonging to the same trophic level, such as phytoplankton, may show functional differences, we investigated whether the effects of environment and dispersal differ among phytoplankton species from different functional groups. We analyzed data from a rainy and a dry period in 30 reservoirs in a subtropical region. In both periods, the environment as well as high and limited dispersal influenced the metacommunity structure. The functional groups had a low correspondence in their response to both dispersal and environment. Our results showed that the influence of the processes underlying the structure of the metacommunities, such as species sorting (environment influence), mass effect (high dispersal), and neutral dynamics (limited dispersal), depended on the functional characteristics of the organisms and could vary even among species of the same trophic level. These findings suggested that species at the same trophic level could not be considered ecological equivalents. This paper includes a Portuguese and Spanish version of the abstract in the online resources. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00027-021-00837-0.

Impoundment, environmental variables and temporal scale predict zooplankton beta diversity patterns in an Amazonian river basin.

The implementation of environmental monitoring programs in areas under anthropogenic pressure is essential to investigate the processes that generate and maintain biodiversity in ecosystems and to establish the most appropriate conservation strategies according to the area. We investigated whether environmental variables or temporal scale influenced zooplankton spatial diversity and beta diversity components in the Madeira River basin (Amazon tributary, Rondônia state, Brazil) from 2009 to 2015. We also investigated the local site contribution to overall beta diversity (LCBD) and to each of its components, to be able to propose conservation strategies more suitable for the river basin. Alpha diversity values decreased over time, while total beta diversity and the abundance difference component increased. A pattern of abundance difference (Podani family) dominated spatial beta diversity within the major sampling campaigns (at each time point). Environmental variables and heterogeneity, temporal scale (sampling campaigns), and also the dam installation contributed to variation in spatial beta diversity and its components. On the other hand, the flood pulse did not influence spatial beta diversity over time. Few sites contributed significantly to beta diversity prior dam installation, but most sites contributed significantly to beta diversity values at least at one point in time, in the post-dam phase. Thus, post-damming, all sites should continue to be monitored for conservation and restoration of zooplankton communities and biodiversity preservation, as changes are likely to still occur. Analysis of beta diversity, its components, and LCBD, are useful and efficient methods to study spatio-temporal changes in communities and identify critical sites. Impoundment and environmental variation significantly affect zooplankton community beta diversity, dependent on underlying mechanisms such as substitution or abundance differences that diversify communities spatially and temporally.

Efficient and nontoxic adenoviral purging method for autologous transplantation in breast cancer patients.

Tumor cell contamination of clinical grafts is a major concern in autologous hematopoietic stem cell transplantation because these contaminating cells can contribute to relapse. In the present work, we use a suicide gene therapy approach that successfully accomplishes the two main goals of any purging strategy: highly efficient elimination of contaminating tumor cells and preservation of the engraftment capability of the hematopoietic progenitor cells. Human CD34(+) cells spiked with breast cancer cells were infected with an adenoviral vector encoding the cytosine deaminase transgene (Ad-CMV-CD). In vitro, transduction with Ad-CMV-CD followed by exposure to 400 micro M 5-fluorocytosine resulted in complete elimination of clonogenic contaminating tumor cells without affecting the clonogenic potential of the human hematopoietic CD34(+) cells. Transplantation of nonobese diabetic/LtSz-scid/severe combined immunodeficient (NOD/SCID) mice with nonpurged contaminated grafts and purged contaminated grafts, allowed us to test the safety and efficacy of our procedure in two independent purging experiments. Hematopoietic engraftment kinetics as well as the quantity and quality of human engraftment were not affected by the purging therapy. Results showed a significant difference in survival between the nonpurged group (28%) and the purged group (100%; P = 0.012). Moreover, highly sensitive histological and molecular analyses confirmed the absence of tumor cells in the recipients of purged marrow. In contrast, metastatic tumors were detected in animals that received nonpurged grafts. We anticipate that this strategy will result in a safe and efficacious hematopoietic graft product for autologous transplantation for patients with multiple forms of epithelial cancers.

HIV-associated lymphoma successfully treated with peripheral blood stem cell transplantation.

OBJECTIVE: To evaluate feasibility, safety, and efficacy of peripheral blood stem cell collection (PBSCC) and autologous stem cell transplantation (ASCT), to treat patients diagnosed of high-risk or relapsed HIV-associated lymphoma (HIV+ Ly), responding to highly active antiretroviral therapy (HAART). METHODS: Prospective and multicentric study in patients with high-risk or relapsed chemosensitive HIV+ Ly, candidate for consolidation with ASCT. Eligibility criteria were similar to those of HIV- lymphoma. HAART was aimed to be maintained during the procedure. RESULTS: Fourteen patients were admitted. Adequate PBSCC was obtained from all patients (median CD34+ cells was 4.7 x 10(6)/kg). Three patients died before ASCT; two had disease progression and one died from VHC-liver failure. Eleven transplanted patients showed neutrophil engraftment after a median time of 16 days (range, 9-33 days), and nine patients showed platelet engraftment after a median time of 20 days (range, 11-36 days). CD4+ cell counts and HIV viral load (VL) were appropriately preserved along the procedure. No patients died from treatment-related complications. One patient died from lymphoma progression (day +19), and another died in complete remission (CR) with undetectable VL, 15 months after transplant, due to infection. One patient relapsed at 32 months after ASCT. The remaining eight patients are alive in CR with an event-free survival of 65% and a median follow-up of 30 months after ASCT (range, 7-36 months). CONCLUSIONS: These results show that feasibility, safety, and efficacy of PBSCC and ASCT in HIV+ Ly patients responding to HAART are similar to those observed in the HIV- lymphoma setting.

Fístula colovesical secundaria a diverticulitis complicada: tratamiento laparoscópico. Reporte de caso / Colovesical fistula secondary to complicated diverticulitis, laparoscopic treatment. A case report

Resumen Introducción: La fístula colovesical es la unión entre la vejiga y el intestino grueso, se presenta en el 2% de los pacientes con enfermedad diverticular del colon, genera síntomas como neumaturia y fecaluria, asociados a infecciones urinarias recurrentes. Los pacientes se diagnostican mediante estudios imagenológicos y su tratamiento generalmente es quirúrgico. Objetivo: Reportar el caso de tratamiento laparoscópico de paciente con fístula colovesical secundaria a diverticulitis complicada. Caso clínico: Se presenta el caso de un paciente masculino de 69 años, con antecedente de enfermedad diverticular, cursando con infección de vías urinarias recurrentes, fecaluria y neumaturia. La cistoscopia no mostró trayecto fistuloso y la tomografía abdominopélvica mostró hallazgos inflamatorios y fístula colovesical asociada a diverticulitis complicada. Durante procedimiento laparoscópico se encuentra absceso pericólico sin evidencia del trayecto fistuloso, se realizó drenaje, sutura del colon e interposición del epiplón, sin resección intestinal. Paciente con adecuada evolución postoperatoria con egreso al sexto día. El objetivo del tratamiento quirúrgico se centra en el control de complicaciones generadas por los divertículos, en este caso, la fístula colovesical. Conclusiones: El procedimiento laparoscópico es de mínima invasión, no presenta la morbilidad que implica una resección de colon o una colostomía y se asocia con una recuperación funcional más rápida.

Abstract Introduction: The colovesical fistula is a junction between the urinary bladder and the large intestine. It occurs in 2% of patients with diverticular disease of the colon and generates symptoms such as pneumaturia and fecaluria associated with recurrent urinary tract infections. The patients are diagnosed by imaging studies and their treatment is usually surgical. Objective: To report the laparoscopic treatment administered to a patient that presented a case of colovesical fistula secondary to severe diverticulitis. Case report: The case of a 69-year-old male patient with a medical record of diverticular disease, who presented recurrent urinary tract infection, fecaluria, and pneumaturia is presented. The cystoscopy procedure showed no signs of anal fistula, and the abdominopelvic tomography showed signals of inflammations and colovesical fistula associated with complicated diverticulitis. During the laparoscopic procedure, a pericolic abscess was found without evidence of anal fistula. Drainage and suture of the colon and omentum interposition were performed without presenting intestinal resection. The patient had an adequate postoperative recovery and was discharged on the sixth day. The aim of this surgical treatment is focused on the control of medical complications caused by diverticulitis, in this case, colovesical fistula. Conclusions: This procedure is minimally invasive, and it is associated with a faster functional recovery since it does not present the morbidity of a colon resection or colostomy.

A comparison of fluorescent in situ hybridization and multiplex short tandem repeat polymerase chain reaction for quantifying chimerism after stem cell transplantation.

BACKGROUND AND OBJECTIVES: Despite the great utility of chimerism analysis after allogeneic stem cell transplantation, a gold standard method for its quantification has not yet been defined. The objective of the present investigation was to compare the sensitivity (detection limit) and the quantification accuracy of fluorescent in situ hybridization with specific probes for the sex chromosomes (XY-FISH) and multiplex short tandem repeat polymerase chain reaction (STR-PCR) revealed by capillary electrophoresis for the quantification of chimerism after stem cell transplantation. DESIGN AND METHODS: A first experiment was performed on two sets of artificial cell mixtures from two sex-mismatched healthy donors mixed in different proportions (% male: 100, 75, 50, 25, 10, 5, 3, 1, 0.1, 0). In a second experiment, 58 samples obtained from 10 selected patients with different clinical courses and chimerism evolution after sex-mismatched stem cell transplantation, which had been studied by XY-FISH, were retrospectively analyzed by STR-PCR. In a third experiment, 60 unselected prospective samples belonging to 15 patients (5 of whom had also been included in the retrospective study) were analyzed by both XY-FISH and STR-PCR. RESULTS: Both techniques showed high quantification accuracy and were highly reproducible. The sensitivity of both approaches reached 1% under standard conditions. Moreover, the use of long injection times for the capillary electrophoresis (30 and 50s vs. the standard 10s) resulted in an increase of sensitivity of the STR-PCR assay up to 0.1%, which has interesting clinical implications. INTERPRETATION AND CONCLUSIONS: Considering the high sensitivity and quantification accuracy of multiplex STR-PCR and the fact that this assay is sex-independent and can be applied to virtually all patients, STR-PCR could be considered as the method of choice for chimerism quantification after stem cell transplantation when high sensitivity is not a requirement.

Migration of human blood dendritic cells across endothelial cell monolayers: adhesion molecules and chemokines involved in subset-specific transmigration.

Distinct subsets of dendritic cells (DCs) are present in blood, probably "en route" to different tissues. We have investigated the chemokines and adhesion molecules involved in the migration of myeloid (CD11c(+)) and plasmacytoid (CD123(+)) human peripheral blood DCs across vascular endothelium. Among blood DCs, the CD11c(+) subset vigorously migrated across endothelium in the absence of any chemotactic stimuli, whereas spontaneous migration of CD123(+) DCs was limited. In bare cell migration assays, myeloid DCs responded with great potency to several inflammatory and homeostatic chemokines, whereas plasmacytoid DCs responded poorly to all chemokines tested. In contrast, the presence of endothelium greatly favored transmigration of plasmacytoid DCs in response to CXCL12 (stromal cell-derived factor-1) and CCL5 (regulated on activation, normal T expressed and secreted). Myeloid DCs exhibited a very potent transendothelial migration in response to CXCL12, CCL5, and CCL2 (monocyte chemoattractant protein-1). Furthermore, we explored whether blood DCs acutely switch their pattern of migration to the lymph node-derived chemokine CCL21 (secondary lymphoid-tissue chemokine) in response to microbial stimuli [viral double-stranded (ds)RNA or bacterial CpG-DNA]. A synthetic dsRNA rapidly enhanced the response of CD11c(+) DCs to CCL21, whereas a longer stimulation with CpG-DNA was needed to trigger CD123(+) DCs responsive to CCL21. Use of blocking monoclonal antibodies to adhesion molecules revealed that both DC subsets used platelet endothelial cell adhesion molecule-1 to move across activated endothelium. CD123(+) DCs required beta(2) and beta(1) integrins to transmigrate, whereas CD11c(+) DCs may use integrin-independent mechanisms to migrate across activated endothelium.

A new approach for bone marrow-derived stem cells intrapancreatic autotransplantation in diabetic rats.

PURPOSE: A new technique for stem cells intrapancreatic autotransplantation in rats. BASIC PROCEDURES: Section of a femoral diaphysis and aspirations of the bone marrow in both femoral segments were performed. A Kirschner needle was placed into the femur. Cells were isolated in Ficoll gradients and preserved at 4-6 degrees C. The second day, cells were injected, via aortic celiac trunk, into the pancreas of the same rat. RESULTS: Femoral surgery were well tolerated. Intrapancreatic homing of the injected cells was suggested with methylene blue injection that stained the pancreas, and proved by labeled cells in pancreas sections. Cell counts after Ficoll isolation were 1 x 10(6) +/- 2 x 10(5) ES. CONCLUSIONS: A technique is described for stem cell autotransplantation in rats. First we obtain autologous bone marrow-derived stem cells. Second, we inject the cells in the pancreas of the donor rat. This approach can be applied to experimental diabetes and other pancreatic processes.

[Blood bank]. / Banco de sangre.

We describe the consequences of the mass arrival of victims and donors on our blood bank. Changes in the organization, interventions and activity related to transfusions and donations are presented. In the conclusion, we critically analyze our experience and discuss ideas that could be applied in future similar situations.

Banco de sangre / Blood Bank

Describimos las consecuencias sobre nuestro banco de sangre de la llegada masiva de víctimas y donantes. Exponemos los cambios organizativos, actuación y actividad de los aspectos transfusionales y de donación. En la conclusión analizamos críticamente la experiencia y aportamos ideas que se puedan aplicar en situaciones similares futuras (AU)

We describe the consequences of the mass arrival of victims and donors on our blood bank. Changes in the organization, interventions and activity related to transfusions and donations are presented. In the conclusion, we critically analyze our experience and discuss ideas that could be applied in future similar situations (AU)