82 research outputs found
Development and clinical application of hydrogel formulations containing papain and urea for wound healing
Hydrogels are used for wound treatment, as they may contain one or more active components and protect the wound bed. Papain is one of the active substances that have been used with this purpose, alongside urea. In this paper, carboxypolymethylene hydrogels containing papain (2% and 10% concentrations) and urea (5% concentration) were produced. Physical-chemical stability was performed at 0, 7, 15 and 30 days at 2-8ÂşC, 25ÂşC and 40ÂşC, as well as the rheological aspects and proteolytic activity of papain by gel electrophoresis. Clinical efficacy of the formulations in patients with lower limb ulcers was also evaluated in a prospective, single-center, randomized, double-blind and comparative clinical trial. The results showed 7-day stability for the formulations under 25ÂşC, in addition to approximately 100% and 15% of protein activity for 10% and 2% papain hydrogel, respectively. The rheological profile was non-Newtonian for the 10% papain hydrogel tested. There were no significant differences regarding the mean time for healing of the lesions, although 10% papain presented a better approach to be used in all types of tissue present in the wound bed
Hexosamine Biosynthetic Pathway and Glycosylation Regulate Cell Migration in Melanoma Cells
The Hexosamine Biosynthetic Pathway (HBP) is a branch of glycolysis responsible for the production of a key substrate for protein glycosylation, UDP-GlcNAc. Cancer cells present altered glucose metabolism and aberrant glycosylation, pointing to alterations on HBP. Recently it was demonstrated that HBP influences many aspects of tumor biology, including the development of metastasis. In this work we characterize HBP in melanoma cells and analyze its importance to cellular processes related to the metastatic phenotype. We demonstrate that an increase in HBP flux, as well as increased O-GlcNAcylation, leads to decreased cell motility and migration in melanoma cells. In addition, inhibition of N- and O-glycosylation glycosylation reduces cell migration. High HBP flux and inhibition of N-glycosylation decrease the activity of metalloproteases 2 and 9. Our data demonstrates that modulation of HBP and different types of glycosylation impact cell migration
Targeting the Hexosamine Biosynthetic Pathway Prevents Plasmodium Developmental Cycle and Disease Pathology in Vertebrate Host
Cerebral malaria (CM) is a clinical syndrome involving irreversible and lethal signs of brain injury associated to infection by parasites of the genus Plasmodium. The pathogenesis of CM derives from infection-induced proinflammatory cytokines associated with cytoadherence of parasitized red blood cells to brain microvasculature. Glycoconjugates are very abundant in the surface of Plasmodium spp., and are critical mediators of parasite virulence in host–pathogen interactions. Herein, we show that 6-Diazo-5-oxo-L-norleucine (DON) therapeutically used for blocking hexosamine biosynthetic pathway leads to recovery in experimental murine cerebral malaria. DON-induced protection was associated with decreased parasitism, which severely reduced Plasmodium transmission to mosquitoes. These findings point to a potential use of DON in combination therapies against malaria
Dysregulated Expression of Glycolipids in Tumor Cells: From Negative Modulator of Anti-tumor Immunity to Promising Targets for Developing Therapeutic Agents
Glycolipids are complex molecules consisting of a ceramide lipid moiety linked to a glycan chain of variable length and structure. Among these are found the gangliosides, which are sialylated glycolipids ubiquitously distributed on the outer layer of vertebrate plasma membranes. Changes in the expression of certain species of gangliosides have been described to occur during cell proliferation, differentiation and ontogenesis. However, the aberrant and elevated expression of gangliosides has been also observed in different types of cancer cells, thereby promoting tumor survival. Moreover, gangliosides are actively released from the membrane of tumor cells, having a strong impact on impairing anti-tumor immunity. Beyond the undesirable effects of gangliosides in cancer cells, a substantial number of cancer immunotherapies have been developed in recent years that have used gangliosides as the main target. This has resulted in successful immune cell- or antibody-responses against glycolipids, with promising results having been obtained in clinical trials. In this review, we provide a general overview on the metabolism of glycolipids, both in normal and tumor cells, as well as examining glycolipid-mediated immune modulation and the main successes achieved in immunotherapies using gangliosides as molecular targets
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Números p-ádicos transcendentes e séries de racionais que convergem em qualquer complemento de Q
Quando tomamos o valor absoluto usual e o completamento de Q em relação Ă mĂ©trica induzida por ele, o resultado Ă© o corpo IR dos nĂşmeros reais; fazendo o mesmo processo com qualquer outro valor absoluto definido em Q, obtemos um dos corpos p-ádicos QP. O propĂłsito deste trabalho Ă© explorar a convergĂŞncia de sĂ©ries em QP e em IR, construindo algumas sĂ©ries de nĂşmeros racionais com propriedades de convergĂŞncia surpreendentes. Provamos tambĂ©m que Ă© possĂvel construir uma sĂ©rie de nĂşmeros racionais que converge em qualquer completamento de Q para um valor prĂ©-fixado de Q e de R.When we consider the completion of Q with respect to the usual absolute value we obtain the field of the real numbers R But if we do the same with respect to any other absolute value of Q we obtain the field of the p -adie numbers QP, where p is a prime. In this work we consider the convergence of series in QP and in lR and construct series of racional numbers with amazing convergence properties. We also prove that it is possible to obtain a series of rational numbers that converges in all completions of Q even if we prescribe its sum in each completion
Números p-ádicos transcendentes e séries de racionais que convergem em qualquer complemento de Q
Quando tomamos o valor absoluto usual e o completamento de Q em relação Ă mĂ©trica induzida por ele, o resultado Ă© o corpo IR dos nĂşmeros reais; fazendo o mesmo processo com qualquer outro valor absoluto definido em Q, obtemos um dos corpos p-ádicos QP. O propĂłsito deste trabalho Ă© explorar a convergĂŞncia de sĂ©ries em QP e em IR, construindo algumas sĂ©ries de nĂşmeros racionais com propriedades de convergĂŞncia surpreendentes. Provamos tambĂ©m que Ă© possĂvel construir uma sĂ©rie de nĂşmeros racionais que converge em qualquer completamento de Q para um valor prĂ©-fixado de Q e de R.When we consider the completion of Q with respect to the usual absolute value we obtain the field of the real numbers R But if we do the same with respect to any other absolute value of Q we obtain the field of the p -adie numbers QP, where p is a prime. In this work we consider the convergence of series in QP and in lR and construct series of racional numbers with amazing convergence properties. We also prove that it is possible to obtain a series of rational numbers that converges in all completions of Q even if we prescribe its sum in each completion
- …