The possibility that the Amazon forest system could soon reach a tipping point, inducing large-scale collapse, has raised global concern
. For 65 million years, Amazonian forests remained relatively ...resilient to climatic variability. Now, the region is increasingly exposed to unprecedented stress from warming temperatures, extreme droughts, deforestation and fires, even in central and remote parts of the system
. Long existing feedbacks between the forest and environmental conditions are being replaced by novel feedbacks that modify ecosystem resilience, increasing the risk of critical transition. Here we analyse existing evidence for five major drivers of water stress on Amazonian forests, as well as potential critical thresholds of those drivers that, if crossed, could trigger local, regional or even biome-wide forest collapse. By combining spatial information on various disturbances, we estimate that by 2050, 10% to 47% of Amazonian forests will be exposed to compounding disturbances that may trigger unexpected ecosystem transitions and potentially exacerbate regional climate change. Using examples of disturbed forests across the Amazon, we identify the three most plausible ecosystem trajectories, involving different feedbacks and environmental conditions. We discuss how the inherent complexity of the Amazon adds uncertainty about future dynamics, but also reveals opportunities for action. Keeping the Amazon forest resilient in the Anthropocene will depend on a combination of local efforts to end deforestation and degradation and to expand restoration, with global efforts to stop greenhouse gas emissions.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
It has been hypothesized that the Neolithic transition towards an agricultural and pastoralist economy facilitated the emergence of human-adapted pathogens. Here, we recovered eight Salmonella ...enterica subsp. enterica genomes from human skeletons of transitional foragers, pastoralists and agropastoralists in western Eurasia that were up to 6,500 yr old. Despite the high genetic diversity of S. enterica, all ancient bacterial genomes clustered in a single previously uncharacterized branch that contains S. enterica adapted to multiple mammalian species. All ancient bacterial genomes from prehistoric (agro-)pastoralists fall within a part of this branch that also includes the human-specific S. enterica Paratyphi C, illustrating the evolution of a human pathogen over a period of 5,000 yr. Bacterial genomic comparisons suggest that the earlier ancient strains were not host specific, differed in pathogenic potential and experienced convergent pseudogenization that accompanied their downstream host adaptation. These observations support the concept that the emergence of human-adapted S. enterica is linked to human cultural transformations.
Previous studies have suggested that macrophages are present during lens regeneration in newts, but their role in the process is yet to be elucidated.
Here we generated a transgenic reporter line ...using the newt, Pleurodeles waltl, that traces macrophages during lens regeneration. Furthermore, we assessed early changes in gene expression during lens regeneration using two newt species, Notophthalmus viridescens and Pleurodeles waltl. Finally, we used clodronate liposomes to deplete macrophages during lens regeneration in both species and tested the effect of a subsequent secondary injury after macrophage recovery.
Macrophage depletion abrogated lens regeneration, induced the formation of scar-like tissue, led to inflammation, decreased iris pigment epithelial cell (iPEC) proliferation, and increased rates of apoptosis in the eye. Some of these phenotypes persisted throughout the last observation period of 100 days and could be attenuated by exogenous FGF2 administration. A distinct transcript profile encoding acute inflammatory effectors was established for the dorsal iris. Reinjury of the newt eye alleviated the effects of macrophage depletion, including the resolution of scar-like tissue, and re-initiated the regeneration process.
Together, our findings highlight the importance of macrophages for facilitating a pro-regenerative environment in the newt eye by regulating fibrotic responses, modulating the overall inflammatory landscape, and maintaining the proper balance of early proliferation and late apoptosis of the iPECs.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary
Pig xenografts represent an alternative source of organs for transplantation. Immunosuppression can prevent rejection, but involves high risk and cost. New anti‐rejection techniques have been ...developed; however, results have not been successful. Few studies have reported xenoantibody levels in xenotransplanted patients with diabetes and no patients have reported a clinical correlation. We analysed anti‐galactose (Gal) and other anti‐pig antibody (APA) levels in xenotransplanted patients with type 1 diabetes and the relation to the clinical outcome. Twenty‐three patients with type 1 diabetes were transplanted with porcine islets inside a device without immunosuppression. Demographic characteristics, insulin dose and xenoantibody levels at different periods were recorded. Anti‐Gal and anti‐pig antibodies were measured through indirect enzyme‐linked immunosorbent assay (ELISA) and haemolytic anti‐pig antibody assay. More than 50% were female; the mean current age, current diabetes duration, diabetes duration at xenotransplantation and time post‐transplantation were: 20·8, 11, 5·5 and 5·7 years, respectively. Insulin doses remained with a mean reduction greater than 33% in more than 50% of the patients. The lowest anti‐Gal antibody levels were related to the highest insulin dose reductions. This relationship could be explained by the device, Sertoli cells and accommodation process.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
is a neglected fungal pathogen for the human being and other mammals. In several fungal systems, Och1 is a Golgi α1,6-mannosyltransferase with a key function in the synthesis of
-linked glycans; ...which are important elements during the host-fungus interplay. The role of
in fungal virulence seems to be species-specific, being an essential component for
virulence and dispensable during the interaction of
with the host.
Here, we silenced
and characterized the phenotype of the mutant strains.
The mutant strains did not show defects in the cell or colony morphology, the growth rate or the ability to undergo dimorphism; but the cell wall changed in both composition and exposure of inner components at the surface. When interacting with human monocytes, the silenced strains had a reduced ability to stimulate TNFα and IL-6 but stimulated higher levels of IL-10. The interaction with human macrophages was also altered, with reduced numbers of silenced cells phagocytosed. These strains showed virulence attenuation in both
and in the mouse model of sporotrichosis. Nonetheless, the cytokine levels in infected organs did not vary significantly when compared with the wild-type strain.
Our data demonstrate that
silencing affects different aspects of the
-host interaction.
Practice patterns of heart failure nurses Prasun, Marilyn A., PhD, CCNS, FAHA; Casida, Jesse, PhD, RN, CCRN-CSC; Howie-Esquivel, Jill, PhD, RN, NP ...
Heart & lung,
05/2012, Volume:
41, Issue:
3
Journal Article
Peer reviewed
Abstract Objective Little is known about the practice patterns of nurses who work in the specialty of heart failure (HF). This specialty includes inpatient and outpatient sites for practice that ...incorporate intensive care to rehabilitation. The purpose of this study was to describe the current practice of nurses who are members of the American Association of Heart Failure Nurses (AAHFN). Methods A convenience sample of nurses attending the 2010 Annual Meeting of AAHFN was surveyed to determine current practice patterns. Results The mean age of the nurses completing the survey was 48 years (standard deviation SD +10), and the majority were white (85%) and female (98%). Approximately half (48%) completed a Master’s degree. The mean time worked as a nurse was 23 years (SD +10), with a mean of 11 years (SD +8.2) caring for patients with HF. Both HF education and physical assessment were reported to be provided frequently. Conclusion This survey provides insight into the practice patterns of HF nurses. Continued monitoring of this role is warranted and can serve to assist the AAHFN in advancing HF knowledge and skills.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Current medical guidelines consider pregnant women with COVID-19 to be a high-risk group. Since physiological gestation downregulates the immunological response to maintain “maternal-fetal ...tolerance”, SARS-CoV-2 infection may constitute a potentially threatening condition to both the mother and the fetus. To establish the immune profile in pregnant COVID-19+ patients, a cross-sectional study was conducted. Pregnant women with COVID-19 (P-COVID-19+; n = 15) were analyzed and compared with nonpregnant women with COVID-19 (NP-COVID-19+; n = 15) or those with physiological pregnancy (P-COVID-19-; n = 13). Serological cytokine and chemokine concentrations, leucocyte immunophenotypes, and mononuclear leucocyte responses to polyclonal stimuli were analyzed in all groups. Higher concentrations of serological TNF-α, IL-6, MIP1b and IL-4 were observed within the P-COVID-19+ group, while cytokines and chemokines secreted by peripheral leucocytes in response to LPS, IL-6 or PMA-ionomicin were similar among the groups. Immunophenotype analysis showed a lower percentage of HLA-DR+ monocytes in P-COVID-19+ than in P-COVID-19- and a higher percentage of CD39+ monocytes in P-COVID-19+ than in NP-COVID-19+. After whole blood polyclonal stimulation, similar percentages of T cells and TNF+ monocytes between groups were observed. Our results suggest that P-COVID-19+ elicits a strong inflammatory response similar to NP-COVID19+ but also displays an anti-inflammatory response that controls the ATP/adenosine balance and prevents hyperinflammatory damage in COVID-19.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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