Scielo RSS <![CDATA[Brazilian Journal of Medical and Biological Research]]> vol. 53 num. 11 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Amifostine protects from the peripheral sensory neuropathy induced by oxaliplatin in mice]]> Sensory neuropathy is a dose-limiting side effect of oxaliplatin-based cancer treatment. This study investigated the antinociceptive effect of amifostine and its potential neuroprotective mechanisms on the oxaliplatin-related peripheral sensory neuropathy in mice. Oxaliplatin (1 mg/kg) was injected intravenously in Swiss albino male mice twice a week (total of nine injections), while amifostine (1, 5, 25, 50, and 100 mg/kg) was administered subcutaneously 30 min before oxaliplatin. Mechanical and thermal nociceptive tests were performed once a week for 49 days. Additionally, c-Fos, nitrotyrosine, and activating transcription factor 3 (ATF3) immunoexpressions were assessed in the dorsal root ganglia. In all doses, amifostine prevented the development of mechanical hyperalgesia and thermal allodynia induced by oxaliplatin (P&lt;0.05). Amifostine at the dose of 25 mg/kg provided the best protection (P&lt;0.05). Moreover, amifostine protected against neuronal hyperactivation, nitrosative stress, and neuronal damage in the dorsal root ganglia, detected by the reduced expression of c-Fos, nitrotyrosine, and ATF3 (P&lt;0.05 vs the oxaliplatin-treated group). In conclusion, amifostine reduced the nociception induced by oxaliplatin in mice, suggesting the possible use of amifostine for the management of oxaliplatin-induced peripheral sensory neuropathy. <![CDATA[Absence of norovirus contamination in shellfish harvested and commercialized in the Northeast coast of Brazil]]> Norovirus (NoV) is the main cause of gastroenteritis outbreaks worldwide. Although NoV spreads mainly from person to person, it is estimated that a large proportion of NoV outbreaks are caused by foodborne transmission. Bivalve mollusks are one of the most important foods involved in NoV transmission to humans. Little is known about NoV prevalence in shellfish harvested and commercialized in Brazil. The aim of this study was to map, for the first time, the distribution of NoV contamination in oysters and mussels harvested and commercialized in the coast of Pernambuco state, northeast Brazil. A total of 380 mollusks (260 oysters and 120 mussels) were collected between February and August 2017 either directly from harvesting areas or obtained from beach vendors at 17 sites in Pernambuco. Samples were processed and tested for NoV contamination using a SYBR Green real-time PCR assay. All samples were negative for NoV GI or GII contamination, suggesting a low risk of NoV contamination from this food source during the study period. Additional surveys in different areas of the Brazilian coast are warranted to monitor the risk of NoV infection upon seafood consumption. <![CDATA[AQP5 regulates the proliferation and differentiation of epidermal stem cells in skin aging]]> The epidermis, the outermost layer of the skin, is the first barrier that comes into contact with the external environment. It plays an important role in resisting the invasion of harmful substances and microbial infections. The skin changes with age and external environmental factors. This study aimed to investigate epidermal stem cells during the process of aging. This study enrolled 9 volunteers with benign pigmented nevus for clinical dermatologic surgery. The phenotypes associated with skin aging changes such as skin wrinkles and elasticity of the unexposed/healthy parts near benign pigmented skin were measured, and epidermal stem cells from this region were isolated for transcriptome sequencing. The results showed that epidermal stem cells could be obtained by magnetic activated cell sorting (MACS) with high purity. Results of the transcriptome sequencing revealed that aquaporin (AQP)5 significantly decreased in the epidermal stem cells with age, and further functional experiments revealed that AQP5 could promote the proliferation and dedifferentiation of HaCaT, but did not influence cell apoptosis. In summary, AQP5 regulated the proliferation and differentiation of epidermal stem cells in skin aging, and it may play an important role in the balance of proliferation and differentiation. However, further studies are needed to determine the mechanism by which AQP5 regulates the proliferation and differentiation of epidermal skin cells in aging. <![CDATA[Endothelial progenitor cells in the peripheral blood of patients with moyamoya disease labeled with superparamagnetic iron oxide <em>in vitro</em> for MRI detection]]> Moyamoya disease (MMD) is currently thought to involve endothelial progenitor cells (EPCs). We investigated whether superparamagnetic iron oxide (SPIO) can be used to label EPCs. Mononuclear cells from 10 moyamoya disease patients were isolated, and cluster of differentiation 133 (CD133) positive cells sorted by magnetic-activated cell sorting were cultured in vitro. The positive rates of CD133, vascular endothelial growth factor receptor (VEGFR)-2, and cluster of differentiation 34 (CD34) were detected by flow cytometry. The cells were co-cultured with fluorescence labeled Dil-acetylated-low-density lipoprotein (Dil-ac-LDL) and Ulex europaeus agglutinin-1 (UEA-1) to observe the endocytosis of Dil-ac-LDL and binding to UEA-1. Prussian blue staining and transmission electron microscopy were used to observe the endocytosis of different SPIO concentrations in EPCs, and CCK-8 was used to detect proliferation of cells transfected with different concentrations of SPIO. T2 weighted imaging (T2WI) signals from magnetic resonance imaging after SPIO endocytosis were compared. Positive rates of CD133, VEGFR-2, and CD34 on sorted mononuclear cells were 68.2±3.8, 57.5±4.2, and 36.8±6.5%, respectively. The double-positive expression rate of CD34 and VEGFR-2 was 19.6±4.7%, and 83.1±10.4% of cells, which showed the uptake of Dil-ac-LDL and binding with UEA-1. The labeling efficiencies of SPIO at concentrations of 25 and 50 μg/mL were higher than for 12.5 μg/mL. The proliferation of cells was not influenced by SPIO concentrations of 12.5 and 25 μg/mL. After labeling, the T2WI of EPCs was reduced. The concentration of 25 μg/mL SPIO had high labeling efficiency detected by magnetic resonance imaging (MRI) without decreased EPCs viability.