RESUMO
BACKGROUND: Prolonged fetal exposure to hyperglycemia may increase the risk of developing abnormal glucose metabolism and type-2 diabetes during childhood, adolescence, and adulthood; however, the mechanisms by which gestational diabetes mellitus (GDM) predisposes offspring to metabolic disorders remain unknown. AIM: To quantify the nerve axons, macrophages, and vasculature in the pancreas from adult offspring born from mouse dams with GDM. METHODS: GDM was induced by i.p. administration of streptozotocin (STZ) in ICR mouse dams. At 12 wk old, fasting blood glucose levels were determined in offspring. At 15 wk old, female offspring born from dams with and without GDM were sacrificed and pancreata were processed for immunohistochemistry. We quantified the density of sensory [calcitonin gene-related peptide (CGRP)] and tyrosine hydroxylase (TH) axons, blood vessels (endomucin), and macro-phages (CD68) in the splenic pancreas using confocal microscopy. RESULTS: Offspring mice born from STZ-treated dams had similar body weight and blood glucose values compared to offspring born from vehicle-treated dams. However, the density of CGRP+ and TH+ axons, endomucin+ blood vessels, and CD68+ macrophages in the exocrine pancreas was significantly greater in offspring from mothers with GDM vs control offspring. Likewise, the microvasculature in the islets was significantly greater, but not the number of macrophages within the islets of offspring born from dams with GDM compared to control mice. CONCLUSION: GDM induces neuronal, vascular, and inflammatory changes in the pancreas of adult progeny, which may partially explain the higher propensity for offspring of mothers with GDM to develop metabolic diseases.
RESUMO
Because of the relative lack of understanding of the neurobiological mechanisms that drive toxic effects of cadmium in bone, the purpose of this study was to characterize a preclinical model of chronic cadmium exposure. Adult male C57BL/6 J mice were exposed to cadmium 25 mg/L (as CdCl2) in drinking water for 16 weeks. During this time, pain-related behaviors including hindpaw mechanical sensitivity and vertical rears were evaluated every four weeks. We assessed changes in bone microarchitecture at the femoral neck and L5 vertebra by microcomputed tomography and quantified the density of nerve fibers expressing PGP 9.5 (a pan-neuronal marker) and CGRP (a marker of sensory nerve fibers subfamily) at the femoral neck and glabrous skin of the hindpaw using immunohistochemistry. Cadmium exposure produced mechanical hypersensitivity in both hindpaws along with decreased rearing activity (surrogate for musculoskeletal-related pain) without affecting the horizontal activity (a measure of locomotor behavior) in comparison to the control group. Intraperitoneal acute treatment with morphine and gabapentin reversed pain-related behaviors in cadmium-exposed mice. Furthermore, exposure to cadmium resulted in significant trabecular bone deterioration at the femoral neck and L5 vertebra. We also observed a significant reduction in the density of both CGRP+ and PGP 9.5+ nerve fibers in the femoral neck, but not in the hindpaw glabrous skin, suggesting tissue-dependent neurotoxicity. This model may help in developing a mechanism-based understanding of the factors that generate and maintain musculoskeletal pain and bone loss caused by chronic cadmium exposure and in translating these findings into new therapies for treating cadmium-induced bone toxicity.
Assuntos
Cádmio , Colo do Fêmur , Animais , Cádmio/toxicidade , Colo do Fêmur/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dor , Microtomografia por Raio-XRESUMO
Cadmium (Cd) is toxic to the skeletal system resulting in bone loss and pain. We aimed at determining the effect of chronic Cd exposure on bone density and microarchitecture along with changes in the density of a subset of sensory and sympathetic nerve fibers innervating the developing rat femur. Newborn male Wistar rats were injected daily for 49 days with CdCl2 (1 mg/kg i.p.) or saline solution (control group). At the day of sacrifice, levels of Cd in the right femur, liver and kidney were determined by atomic absorption spectrophotometry. Additionally, microCT followed by immunohistochemical analyses were performed in the left femur. Results showed Cd accumulation in trabecular bone neared levels seen in liver and kidney. Cd concentration in cortical bone was significantly lower versus trabecular bone. MicroCT analysis revealed that Cd-exposed rats had a significant decrease in trabecular bone parameters at the distal femoral metaphysis; however, most of the cortical bone parameters were not significantly affected. Cd-exposed rats showed a significant loss of TH+ sympathetic nerve fibers, but not of CGRP+ sensory nerve fibers, at the level of bone marrow of the femoral diaphysis as compared to control rats. This study shows that Cd negatively affects bone density and microarchitecture of trabecular bone and decreases the density of sympathetic nerve fibers innervating rat femur. Future studies are warranted to determine the toxigenic mechanisms of Cd on sympathetic nerves and how sympathetic denervation influences bone loss in animals exposed to Cd.
Assuntos
Densidade Óssea/efeitos dos fármacos , Cádmio/toxicidade , Osso Esponjoso/efeitos dos fármacos , Fêmur/efeitos dos fármacos , Fibras Nervosas/efeitos dos fármacos , Animais , Cádmio/administração & dosagem , Feminino , Fêmur/crescimento & desenvolvimento , Injeções Intraperitoneais , Gravidez , Ratos , Ratos WistarRESUMO
PURPOSE: This study sought to determine the prevalence of myopia in schoolchildren of a rural population in Mexico. METHODS: A cross-sectional study was conducted in 317 children between 6 and 12 years old. A complete refractive examination was performed, including static retinoscopy without cycloplegic agents. All procedures were conducted according to the Declaration of Helsinki. RESULTS: In total, 9.7% (95% CI: 13.07-6.52) of the examined children were myopic (spherical equivalent ≤ -0.50 D), 4.4% (95% CI: 6.66-2.14) presented astigmatism (cylinder ≤ -1.50 D), and 5.4% (95% CI: 7.89-2.91) presented hyperopia (spherical equivalent ≥ +0.50 D). CONCLUSION: Additional research is required to assess the prevalence of refractive errors in rural areas in Mexico, to analyze the associated risk factors, and to implement appropriate eye care plans for this population.
RESUMO
Las lesiones penetrantes por arma blanca a nivel espinal son relativamente raras. Estas lesiones podrían ser fácilmente diagnosticadas al examen inicial o podrían tener complicaciones tardías que son incapacitantes y potencialmente letales. Algunas de estas lesiones requieren tratamiento neuroquirúrgico. Se presenta un cso en el cual un paciente con lesión penetrante por arma blanca se complicó tardíamente con una fístula de líquido cefalorraquídeo y meningitis bacteriana debido a cuerpo extraño retenido no diagnosticado inicialmente, fragmento de cuchillo.