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71.
We present the case of a 57 years old woman which was admitted for the amputation of the infero-nasal visual field of the right eye, change observed by the pacient for 2 weeks. Clinical examination and lab exams revealed the cause of this change: a rhegmatogenous retinal detachment in the superior temporal quadrant. Surgical treatement was warranted. We did a posterior vitrectomy with trans-scleral crioapplications and injection of silicone oil 1000. We followed the patient's evolution post-operative and we observed the development of a complicated cataract which was treated in a second surgery together with the extraction of the silicone oil. The evolution was favorable.  相似文献   
72.
Myeloproliferative neoplasm (MPN)‐associated myelofibrosis is a clonal, neoplastic disorder of the hematopoietic stem cells, in which inflammation and immune dysregulation play an important role. Extracellular nicotinamide phosphoribosyltransferase (eNAMPT), also known as visfatin, is a cytokine implicated in a number of inflammatory and neoplastic diseases. Here plasma levels of eNAMPT in patients with MPN‐associated myelofibrosis and their effects on disease phenotype and outcomes were examined. The concordance of eNAMPT levels with the marker of general inflammation high‐sensitivity C‐reactive protein (hs‐CRP) was also studied. A total of 333 MPN‐associated myelofibrosis patients (187 males and 146 females) and 31 age‐ and gender‐matched normal‐weight healthy subjects were enrolled in the study main body. Levels of eNAMPT and hs‐CRP were simultaneously assayed in 209 MPN‐associated myelofibrosis patients. Twenty‐four polycythemia vera or essential thrombocythemia patients were used as controls. eNAMPT was over expressed in MPN‐associated myelofibrosis, and eNAMPT expression was correlated with higher white blood cell count, higher hemoglobin, and higher platelet count, suggesting that eNAMPT is an indispensable permissive agent for myeloproliferation of MPN‐associated myelofibrosis. The lack of correlation between eNAMPT and hs‐CRP revealed that eNAMPT in MPN‐associated myelofibrosis does not behave as a canonical inflammatory cytokine. In addition, higher levels of eNAMPT predicted longer time to blast transformation, and protected against progression toward thrombocytopenia and large splenomegaly. In conclusion, in MPN‐associated myelofibrosis high levels of eNAMPT mark the myeloproliferative potential and, at variance with a high number of cancers, are protective against disease progression. Am. J. Hematol. 91:709–713, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
73.
The masticatory muscles differ in their fiber type composition. It can therefore be expected that their electromyographic (EMG) power spectra will differ during the performance of different bite force tasks. In the present study, surface EMG activity was picked up from the masseter and from the anterior and posterior temporalis muscles of nine adult subjects. At a bite force level as low as 25 N, the mean power frequency (MPF) values of the posterior temporalis were significantly lower than those of the masseter and anterior temporalis. The MPF values of the masseter muscles decreased with an increase of bite force magnitude, whereas the MPF values of the anterior and posterior temporalis did not change significantly. The MPF values were significantly influenced by the direction of bite force. The observed changes of MPF are possibly related to the recruitment of different fiber types, and support the concept that the masticatory muscles behave heterogeneously.  相似文献   
74.

Objective

The objective of this study was to examine whether the risk of sine causa recurrent miscarriage is associated with caffeine consumption during the periconceptional period and early gestation after controlling for pregnancy-related symptoms.

Study design

A retrospective case–control study was conducted in the Department of Obstetrics and Gynecology, University of Turin between 2008 and 2009. Fifty-two sine causa recurrent miscarriers and 260 healthy pregnant women were assessed. Data were analyzed using SPSS 17 for Windows.

Results

Caffeine consumption during the periconceptional period and early gestation was higher in sine causa recurrent miscarriers compared to healthy pregnant women. Moreover, each caffeine intake of 100 mg/day was associated with an increased odds ratio for sine causa recurrent miscarriage of 2724 (p for trend 0.001; 95% confidence interval [CI], 2.715–2.733), after adjusting for relevant confounding covariates.

Conclusion

Caffeine intake may increase the risk of sine causa recurrent miscarriage regardless of pregnancy-related symptoms and relevant covariates (such as age and tobacco use).  相似文献   
75.
The hepatitis B virus is responsible for most of the chronic liver disease and liver cancer worldwide. As actual therapeutic strategies have had little success in eradicating the virus from hepatocytes, and as lifelong treatment is often required, new drugs targeting the various phases of the hepatitis B virus (HBV) lifecycle are currently under investigation. In this review, we provide an overview of potential future treatments for HBV.  相似文献   
76.
Transforming growth factor-beta (TGF-beta) cooperates with oncogenic members of the Ras superfamily to promote cellular transformation and tumor progression. Apart from the classic (H-, K-, and N-) Ras GTPases, only the R-Ras subfamily (R-Ras, R-Ras2/TC21, and R-Ras3/M-Ras) has significant oncogenic potential. In this study, we show that oncogenic R-Ras transformation of EpH4 cells requires TGF-beta signaling. When murine EpH4 cells were stably transfected with a constitutively active R-Ras(G38V) mutant, they were no longer sensitive to TGF-beta-mediated growth inhibition and showed increased proliferation and transformation in response to exogenous TGF-beta. R-Ras/EpH4 cells require TGF-beta signaling for transformation to occur and they produce significantly elevated levels of endogenous TGF-beta, which signals in an autocrine fashion. The effects of TGF-beta are independent of Smad2/3 activity and require activation of TGF-beta-associated kinase 1 (TAK1) and its downstream effectors c-Jun NH(2)-terminal kinase and p38 mitogen-activated protein kinase as well as the phosphoinositide 3-kinase/Akt and mammalian target of rapamycin pathways. Thus, TAK1 is a novel link between TGF-beta signaling and oncogenic R-Ras in the promotion of tumorigenesis.  相似文献   
77.
We retrospectively analyzed sequential therapy with romiplostim and eltrombopag in 23 children with immune thrombocytopenia: switching from romiplostim to eltrombopag (10 patients) or vice versa (13 patients). The median age of patients at enrollment in the study was 5.6 years (2‐15 years). Switching from romiplostim to eltrombopag was effective in eight (80%) patients, whereas switching from eltrombopag to romiplostim was effective in eight (62%) patients. The response rate was similar in patients failing the first thrombopoietin receptor agonist and those who had previous response. To date, all responders continue to maintain platelets over 50 × 109/L at 13‐39 months after switching.  相似文献   
78.
As nanoparticles (NPs) can access the brain and impact on CNS function, novel in vitro models for the evaluation of NPs-induced neurotoxicity are advocated. Three-dimensional spheroids of primary neuron-like cells (hNLCs) of human origin have been generated, from differentiation of human umbilical cord mesenchymal stem cells (MSCs). The study evaluated Fe3O4NP impact on the differentiation process by applying the challenge at complete 3D hNLC spheroid formation (after 4 days, T4) or at beginning of neurogenic induction/simultaneously 3D forming (T0). Different endpoints were monitored over time (up to 10 days): spheroid growth, size, morphology, ATP, cell death, neuronal markers (β-Tub III, MAP-2, and NSE), NP uptake. At T0 application, a marked concentration- and time-dependent cell mortality occurred: effect started early (day 2) and low concentration (1 μg/ml) and exacerbated (80% mortality) after prolonged time (day 6) and increased concentrations (50 μg/ml). ATP was strikingly affected. All neuronal markers were downregulated, and spheroid morphology altered in a concentration-dependent manner (from ≥5 μg/ml) after day 2. Fe3O4NPs applied at complete 3D formation (T4) still induced adverse effects although less severe: cell mortality (20–60%) and ATP content decrease (10–40%) were observed in a concentration-dependent manner (from ≥ 5 μg/ml). A neuronal-specific marker effect and spheroid size reduction from 25 μg/ml without morphology alteration were evidenced. This finding provides additional information on neurotoxic effects of Fe3O4NPs in a new 3D hNLC spheroid model derived from MSCs that could find a consistent application as in a testing strategy serving in first step hazard identification for correct risk assessment.  相似文献   
79.
80.
ABSTRACT

Supplementation with antioxidants received interest as suitable tool for preventing or reducing exercise-related oxidative stress possibly leading to improvement of sport performance in athletes.

To date, it is difficult to reach a conclusion on the relevance of antioxidants supplementation in athletes and/or well-trained people. The general picture that emerges from the available data indicates that antioxidants requirement can be covered by dosage equal or close to the recommended dietary allowance (RDA) provided by consumption of a balanced, well-diversified diet. Nevertheless, it remains open the possibility that in specific context, such as in sports characterized by high intensity and/or exhaustive regimes, supplementation with antioxidants could be appropriated to avoid or reduce the damaging effect of these type of exercise. This review will discuss the findings of a number of key studies on the advantages and/or disadvantages for athletes of using antioxidants supplementation, either individually or in combination.  相似文献   
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