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Progesterone displays a strong potential for the treatment of neonatal hypoxic-ischemic encephalopathy since it has been shown to be beneficial in the treatment of the central nervous system injuries in adult animals. Here, we evaluated the effects of the administration of progesterone (10 mg/kg) in seven-days-old male Wistar rats submitted to neonatal hypoxia-ischemia (HI). Progesterone was administered immediately before ischemia and/or 6 and 24 h after the onset of hypoxia. The body weight of the animals, the volume of brain lesion and the expression of p-Akt and procaspase-3 in the hippocampus were evaluated. All animals submitted to HI showed a reduction in the body weight. However, this reduction was more remarkable in those animals which received progesterone before surgery. Administration of progesterone was unable to reduce the volume of brain damage caused by HI. Moreover, no significant differences were observed in the expression of p-Akt and procaspase-3 in animals submitted to HI and treated with either progesterone or vehicle. In summary, progesterone did not show a neuroprotective effect on the volume of brain lesion in neonatal rats submitted to hypoxia-ischemia. Furthermore, progesterone was unable to modulate p-Akt and procaspase-3 signaling pathways, which may explain the absence of neuroprotection. On the other hand, it seems that administration of progesterone before ischemia exerts some systemic effect, leading to a remarkable reduction in the body weight.  相似文献   
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The occlusal forces and their influence on the initiation of peri‐implant bone loss or their relationship with peri‐implantitis have created discussion during the past 30 years given the discrepancies observed in clinical, animal, and finite element analysis studies. Beyond these contradictions, in the case of an osseointegrated implant, the occlusal forces can influence the implant‐bone interface and the cells responsible for the bone remodeling in different ways that may result in the maintenance or loss of the osseointegration. This comprehensive review focuses on the information available about the forces transmitted through the implant‐crown system to the implant‐bone interface and the mechano‐transduction phenomena responsible for the bone cells’ behavior and their interactions. Knowledge of the basic molecular biology of the peri‐implant bone would help clinicians to understand the complex phenomenon of occlusal forces and their effects on the implant‐bone interface, and would allow better control of the negative effects of mechanical stresses, leading to therapy with fewer risks and complications.  相似文献   
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Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, characterized by focal neurological dysfunction with a relapsing and remitting course. Tumor-like presentation of MS (or “tumefactive”/“pseudotumoral” presentation) has been described before with a certain frequency; it consists of a large single plaque (>2 cm) with presence of edema and mass effect and it is hard to distinguish from a brain tumor. However, we present a very rare case of a 53-year-old woman with a right temporal mass that turned out to be a MS plaque, who deteriorated within hours (brain herniation with loss of consciousness and unilateral mydriasis) and required an emergency craniotomy. We also present a review of the literature. It appears that only 4 cases of emergency craniotomy/craniectomy required in a patient with a tumor-like MS plaque have been reported before.  相似文献   
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The aim of this study was to assess the levels of oxidative, inflammatory, and fibrinolytic biomarkers as well as DNA strand breakage in hypercholesterolemic subjects. Fasting glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, uric acid, total protein, albumin, apolipoprotein (Apo) A, Apo B, advanced oxidation protein products (AOPP), increased ischemia-modified albumin (IMA), ―SH, NOx, IL-6, and D-dimer levels were assessed, and DNA strand breakage was evaluated using comet assay in 38 patients with hypercholesterolemia and 20 healthy controls. Total cholesterol, triglycerides, LDL cholesterol, Apo A, Apo B, AOPP, IMA, IL-6, and D-dimer concentrations were significantly higher in subjects with hypercholesterolemia. However, NOx and plasma ―SH group concentrations were lower in hypercholesterolemic subjects, while no significant differences were observed with respect to DNA strand breakage between the two groups. Hypercholesterolemia is related to oxidative stress and inflammation. Accordingly, AOPP concentration was higher in subjects with hypercholesterolemia, and we speculate that AOPP can reflect the enhancement of protein oxidation and inflammation.  相似文献   
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In this illustrative case, rheumatoid disease changed an active, self-supporting woman into a disabled, dependent and depressed person. When disease activity is continuous, early efforts to prevent severe deformity take on great urgency. It is also important to alleviate the psychosocial impact of the disease, which may well be more than even a highly motivated patient can handle alone.  相似文献   
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