15 research outputs found
Habitat specificity of a threatened and endemic cliff-dwelling halophyte
Research ArticleCoastal areas and other saline environments are major contributors to regional and global biodiversity
patterns. In these environments, rapidly changing gradients require highly specialized plants like halophytes.
In European coastal cliff-tops, rocky and sandy seashores, and saltmarshes, typical halophytes from the genus
Limonium are commonly found. Among them, the aneuploid tetraploid (2n ¼ 4x ¼ 35, 36, 37) Limonium multiflorum,
endemic to the west coast of Portugal, is an interesting case study for investigating the ecology and conservation
of a halophyte agamospermic species. Although it is listed in the IUCN red list of threatened species,
information on its population size or rarity, as well as its ecology, in some respects is still unknown. Field surveys
in the largest known population were performed (Raso cape, Portugal) in order to determine habitat requirements
and conservation status. A total of 88 quadrats were monitored, 43 of which contained at least one L. multiflorum
individual. For each sampled quadrat, four abiotic and four biotic variables as well as two spatially derived variables
were recorded. Principal component analysis and cluster analysis showed narrow habitat specificity for this species
which appeared to be intolerant to competition with invasive alien plants. We conclude that in situ conservation
in a local ‘hotspot’ of this rare and vulnerable species emerges as a priority in order to ensure that biodiversity is not los
The Role of Soy in Vegetarian Diets
Soyfoods have long been prized among vegetarians for both their high protein content and versatility. Soybeans differ markedly in macronutrient content from other legumes, being much higher in fat and protein, and lower in carbohydrate. In recent years however, soyfoods and specific soybean constituents, especially isoflavones, have been the subject of an impressive amount of research. Nearly 2,000 soy-related papers are published annually. This research has focused primarily on the benefits that soyfoods may provide independent of their nutrient content. There is particular interest in the role that soyfoods have in reducing risk of heart disease, osteoporosis and certain forms of cancer. However, the estrogen-like effects of isoflavones observed in animal studies have also raised concerns about potential harmful effects of soyfood consumption. This review addresses questions related to soy and chronic disease risk, provides recommendations for optimal intakes, and discusses potential contraindications. As reviewed, the evidence indicates that, with the exception of those individuals allergic to soy protein, soyfoods can play a beneficial role in the diets of vegetarians. Concerns about adverse effects are not supported by the clinical or epidemiologic literature. Based on the soy intake associated with health benefits in the epidemiologic studies and the benefits noted in clinical trials, optimal adult soy intake would appear to be between two and four servings per day
Genetically Modified Donor Leukocyte Transfusion and Graft-Versus-Leukemia Effect After Allogeneic Stem Cell Transplantation
Seven patients with acute myeloid leukemia (AML) and two patients with chronic myelogenous leukemia (CML) were transplanted from HLA-identical sibling donors with CD34+ cell-enriched stem cells (HSCTs) without further immunosuppression. The myeloablative standard transplantation protocol was adapted to include transfusion of gene-modified donor T cells after HSCT. Donor T cells were transduced with the replication-deficient retrovirus SFCMM-3, which expresses herpes simplex thymidine kinase (HSV-Tk) and a truncated version of low-affinity nerve growth factor receptor (ΔLNGFR) for selection and characterization of transduced cells. Transduced T cells were detectable in all patients during follow-up for up to 5 years after transfusion. Proteomic screening for development of acute graft-versus-host disease (aGvHD) was applied to five of the seven patients with AML. No positivity for the aGvHD grade II-specific proteomic pattern was observed. Only one patient developed aGvHD grade I. To date, three of the patients with AML relapsed; one responded to three escalating transfusions of lymphocytes from the original donor and is in complete remission. Two were retransplanted with non-T cell-depleted peripheral blood stem cells from their original donors and died after retransplantation of septic complications or relapse, respectively. In one patient with CML, loss of bcr-abl gene expression was observed after an expansion of transduced cells. Seven of nine patients are alive and in complete remission
Survey of electrically evoked responses in the retina - stimulus preferences and oscillation among neurons
Abstract Electrical stimulation is an important tool in neuroscience research and clinically. In the retina, extensive work has revealed how the retinal ganglion cells respond to extracellular electrical stimulation. But little is known about the responses of other neuronal types, and more generally, how the network responds to stimulation. We conducted a survey of electrically evoked responses, over a range of pulse amplitudes and pulse widths, for 21 cell types spanning the inner two layers of the rabbit retina. It revealed: (i) the evoked responses of some neurons were charge insensitive; (ii) pulse-width sensitivity varied between cell types, allowing preferential recruitment of cell types; and (iii) 10–20 Hz damped oscillations across retinal layers. These oscillations were generated by reciprocal excitatory / inhibitory synapses, at locations as early as the cone-horizontal-cell synapses. These results illustrate at cellular resolution how a network responds to extracellular stimulation, and could inform the development of bioelectronic implants for treating blindness