ABSTRACT
The mangrove's sediments from the coastal areas under human activities may contain significant contaminations by hydrocarbons, even when there are no visual evidences of it. The microorganisms are essential to these ecosystems, especially in the control of their chemical environment. Sediment samples were collected in two regions under different environment conditions (pristine and contaminated) of the Paranaguá Estuarine Complex (Paranaguá Bay and Laranjeiras Bay), Brazil. Aliphatic hydrocarbons were determined by the GC-FID to assess the status of contamination of the studied areas. The total DNA was extracted from these samples. The 16S rRNA gene was amplified by the PCR reactions with the pair of primers 21F and 958R for the archaeal domain, and 27F and 1492R for the bacterial domain. Comparisons of communities were made by the ARDRA technique, using the HinfI restriction enzyme. The phosphate concentration showed significant differences between the two regions. The aliphatic hydrocarbons analysis showed the presence of unresolved complex mixture (UCM), an indicator of oil contamination, in the samples from the Paranaguá Bay, which was corroborated by the concentration of total aliphatic hydrocarbons. The ARDRA profile indicated that the structure of archaeal and bacterial communities of the sampled areas was very similar. Therefore, the anthropogenic influences in the Paranaguá Bay showed to be not sufficient to produce disturbances in the prokaryotic dominant groups.
ABSTRACT
Chronic hyperglycemia, which is present in all types of diabetes, increases the formation of advanced glycation end-products (AGEs). The interaction of AGEs with receptor of advanced glycation end-products (RAGE) initiates a cascade of pro-inflammatory and pro-coagulant processes that result in oxidative stress, stimulating the formation and accumulation of more AGE molecules. This cyclic process, denominated metabolic memory, may explain the persistency of diabetic vascular complications in patients with satisfactory glycemic control. The RAGE found in several cell membranes is also present in soluble isoforms (esRAGE and cRAGE), which are generated by alternative deoxyribonucleic acid splicing or by proteolytic cleavage. This review focuses on new research into these mediators as potential biomarkers for vascular complications in diabetes.
A hiperglicemia crônica, presente em todas as formas de diabetes, favorece a formação de produtos finais de glicação avançada (AGEs). A interação de AGEs com o receptor de produtos finais glicosilados (RAGE) inicia uma cascata de processos pró-inflamatórios e pró-coagulantes que resultam em estresse oxidativo, o qual estimula a formação e o acúmulo de maior quantidade de moléculas de AGEs. Esse processo cíclico, denominado memória metabólica, pode explicar por que, mesmo após um período de bom controle glicêmico, as complicações vasculares associadas ao diabetes não regridem. O RAGE fixado nas membranas de várias células também está presente em isoformas solúveis (esRAGE e cRAGE), geradas por processamento alternativo do ácido desoxirribonucleico (DNA) ou por clivagem proteolítica. Esta revisão aborda os novos estudos sobre a função desses mediadores como potenciais biomarcadores para as complicações vasculares no diabetes.