Effects of inorganic mercury exposure in the alveolar bone of rats: an approach of qualitative and morphological aspects

Pró-Reitoria de Pesquisa (PACI/PROPESP/UFPA/ Brazil), Brazilian National Council for Scientific and Technological Development (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brazil (CAPES) – Finance Cod 001Background: In comparison to organic mercury (MeHg), the environmental inorganic mercury (IHg) can be found in some skin-lightening cosmestics were considered “harmless” for a long time. However, recent studies have shown that long-term exposure to low doses of IHg may affect biological systems. Therefore, this study investigated the effects of IHg long-term exposure to the alveolar bone of adult rats. Methods: Adult Wistar rats were distributed in control and HgCl2 exposed (0.375 mg/kg/day). After 45 days, the rats were euthanized and both blood and hemimandibles were collected. Total blood Hg levels were measured and both inorganic and organic components of the alveolar bone were determined through XRD and ATR-FTIR. The microstructure of the alveolar bone was assessed by using micro-CT and the morphometric analysis was performed by using stereomicroscopy. Results: Alterations in the physicochemical components of the alveolar bone of exposed animals were observed. The bone changes represented a tissue reaction at the microstructural level, such as bone volume increase. However, no significant dimensional changes (bone height) were observed. Conclusion: Exposure to IHg at this dose can promote microstructural changes and alteration in the organic and inorganic components in the alveolar bone.publishersversionpublishe

Medical residency in gynecology and obstetrics in times of COVID-19 : recommendations of the National Specialized Commission on Medical Residency of FEBRASGO

* Text prepared by the members of the National Specialized Commission on Medical Residency and endorsed by the Scientific Board and Presidency of the Brazilian Federation of Gynecology and Obstetrics Associations (FEBRASGO)

Lipoid pneumonia in a 40-day-old infant

38453553

Relationship between angiotensin-(1-7) and angiotensin II correlates with hemodynamic changes in human liver cirrhosis

AIM: To measure circulating angiotensins at different stages of human cirrhosis and to further evaluate a possible relationship between renin angiotensin system (RAS) components and hemodynamic changes

Spatial variability of soils and stream sediments and the remediation effects in a Portuguese uranium mine area

The old Senhora das Fontes uranium mine, located in central Portugal, was closed down in 1971. Thetreatment of ores from this mine and other mines by heap-leach ended in 1982. Seven dumps partiallycovered by vegetation were left in the area. Soil and stream sediment samples were collected in December2009. The remediation was carried out from May 2010 to January 2011. Stream sediment samples werecollected again in October 2013. Before the remediation, soils from inside the mine influence area havehigher Al, As, Co, Cr, Cu, Fe, Ni, Sr, Th, U and Zn concentrations than soils from outside this area, due toradionuclides, metals and metalloid released from the mine dumps. The principal component analysis(PCA) shows a distinction between soils from inside and outside the mine influence area. The U(VI),As(V) and metals from soils can be adsorbed to Fe-oxyhydroxides and the humic acid can increase theU uptake. Soils must not be used for public or private green and residential areas, because they arecontaminated in U, As, Co, Cd and Ni. Before the remediation, downstream sediments have higher Al, As,Cu, Mn, Ni, Pb, U and Zn than upstream sediments, due to erosion and percolation of water through themine dumps. The PCA shows a distinction between downstream and upstream sediments. The U(VI), Thand As(V) can be adsorbed to Fe-oxyhydroxides. The stream sediments are contaminated in As, Mn, Thand U. Downstream sediments are the most contaminated in U and As. After the remediation, upstreamand downstream sediments have generally higher Al, Fe, As, Cr, Ni, Th, U and Zn concentrations thanbefore the remediation, attributed to the relocation of dumps. Radionuclides, metals and metalloidswere transported by surface water. Consequently downstream sediments have higher Al, As, Cu, Mn,Ni, Th, U and Zn concentrations than upstream sediments. The U(VI), Th and As(V) can be adsorbedto Fe-oxyhydroxides. Stream sediments became more contaminated in U, Th and As than before theremediation, but more intensively downstream.FCT - UID/GEO/04035/201