Prognosis of myasthenia gravis: a retrospective study of 380 patients

The 9139 follow-up records of 438 myasthenia gravis (MG) patients were reviewed. Excluding those patients who were diagnosed 5 or more years after symptom onset (n = 37) and those who experienced only oculomotor symptoms throughout follow-up (n = 21), there were 380 patients. A survival analysis approach was used to assess the influence of prognostic factors on the following endpoints: (a) stable complete remission, (b) complete remission of at least 6 months and (c) pharmacological remission of at least 6 months. Early diagnosis was associated with a better prognosis with respect to all endpoints. Thymectomy also improved the prognosis but only for those patients without thymoma. Later MG onset was associated with a higher tendency to achieve pharmacological remission.     

选择射频电感

额定电流.直流电阻.Q值以及自谐振频率都是重要因素 在手机、RFID,测试设备、GPS、雷达、Wi-Fi以及卫星无线电等应用的高频模拟电路和信号处理中,电感是最重要的元件之一.通常,它可以承担的几项主要功能包括电路调谐、阻抗匹配,高通和低通滤波器,还可以用作RF扼流圈.     

L-Carnitine Functionalization to Increase Skeletal Muscle Tropism of PLGA Nanoparticles

Muscular dystrophies are a group of rare genetic pathologies, encompassing a variety of clinical phenotypes and mechanisms of disease. Several compounds have been proposed to treat compromised muscles, but it is known that pharmacokinetics and pharmacodynamics problems could occur. To solve these issues, it has been suggested that nanocarriers could be used to allow controlled and targeted drug release. Therefore, the aim of this study was to prepare actively targeted poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) for the treatment of muscular pathologies. By taking advantage of the high affinity for carnitine of skeletal muscle cells due to the expression of Na⁺-coupled carnitine transporter (OCTN), NPs have been actively targeted via association to an amphiphilic derivative of L-carnitine. Furthermore, pentamidine, an old drug repurposed for its positive effects on myotonic dystrophy type I, was incorporated into NPs. We obtained monodispersed targeted NPs, with a mean diameter of about 100 nm and a negative zeta potential. To assess the targeting ability of the NPs, cell uptake studies were performed on C2C12 myoblasts and myotubes using confocal and transmission electron microscopy. The results showed an increased uptake of carnitine-functionalized NPs compared to nontargeted carriers in myotubes, which was probably due to the interaction with OCTN receptors occurring in large amounts in these differentiated muscle cells.     

细菌驱动微转子马达

日本国家高级工业科学与技术研究所的一个研究组正在利用快速移动的细菌来驱动微转子马达，这是第一个在无机材料中加进了细菌的微机械器件。这种生物分子马达能比传统的马达更有效的将化学能转化为机械能，还能在大型结构中发挥自修复和自组织的潜能，有望用在微型机器人和微小电子系统中。     

Lamivudine treatment for chronic replicative hepatitis B virus infection after allogeneic bone marrow transplantation

The risk of severe hepatic damage in patients with chronic hepatitis B virus (HBV) infection is well known; more effective treatments for this infection are needed. Lamivudine is being studied in immunocompetent and immunosuppressed HBV infected patients. We report a patient suffering from chronic replicative HBV infection after allogeneic BMT, who responded to lamivudine therapy. A 24-year-old woman with CML received an allogeneic BMT from her HLA-identical sister in June 1992. Before transplant, her HBV status demonstrated viral contact without active infection (HBsAb+, HBcAb+ IgG, HBeAb+). Four months after BMT mild chronic liver GVHD appeared, requiring immunosuppressive treatment. Antibodies to HBV completely disappeared post-transplant. Acute icteric hepatitis occurred 2 years later, with HBsAg+, high level of HBV-DNA, HBeAg+ and HBcAb IgM+. Lamivudine 100 mg/day rapidly reduced transaminase levels and effected HBV-DNA disappearance within 2 months. The treatment was well tolerated; no hematological side-effects occurred. This preliminary observation warrants further investigation of lamivudine treatment in bone marrow transplanted patients with active HBV infection.     

Antioxidant activity of tomato lipophilic extracts and interactions between carotenoids and α-tocopherol in synthetic mixtures

In the present study we assayed the antioxidant activity of lipophilic extracts obtained from different tomato varieties. The results showed that cherry tomatoes, characterized by a high carotenoid content, had the highest antioxidant activity. A quantitative analysis of lycopene, β-carotene, lutein and α-tocopherol was also performed and the correlation between the antioxidant content and the antioxidant activity was estimated. The highest correlation coefficient was found for lycopene (R² = 0.9236, P ≤ 0.001). The analysis of two-component mixtures containing α-tocopherol and carotenoids showed that significant synergism occurred for all the combinations which contained α-tocopherol and β-carotene mixed together. The highest synergistic effects were detected for α-tocopherol-lycopene mixtures, which were the most efficient combinations tested in the present study. The analysis of the carotenoid combinations indicated that synergism occurred for lycopene-β-carotene, lycopene-lutein and lutein-β-carotene mixtures. The analysis of four-component mixtures did not show statistically significant synergistic effects.     

Metal‐Based Nanomaterials in Biomedical Applications: Antimicrobial Activity and Cytotoxicity Aspects

Microbial colonization on material surfaces is ubiquitous. Biofilms derived from surface‐colonized microbes pose serious problems to the society from both an economical perspective and a health concern. Incorporation of antimicrobial nanocompounds within or on the surface of materials, or by coatings, to prevent microbial adhesion or kill the microorganisms after their attachment to biofilms, represents an important strategy in an increasingly challenging field. Over the last decade, many studies have been devoted to preparing meta‐based nanomaterials that possess antibacterial, antiviral, and antifungal activities to combat pathogen‐related diseases. Herein, an overview on the state‐of‐the‐art antimicrobial nanosized metal‐based compounds is provided, including metal and metal oxide nanoparticles as well as transition metal nanosheets. The antimicrobial mechanism of these nanostructures and their biomedical applications such as catheters, implants, medical delivery systems, tissue engineering, and dentistry are discussed. Their properties as well as potential caveats such as cytotoxicity, diminishing efficacy, and induction of antimicrobial resistance of materials incorporating these nanostructures are reviewed to provide a backdrop for future research.     

The preparation of high conversion polymeric systems containing eugenol residues and their rheological characterization

Copolymeric systems bearing eugenol covalently linked to the macromolecular chains have been prepared and characterised in terms of thermal, rheological and in vitro behaviour. Eugenyl methacrylate (EgMA) and ethoxyeugenyl methacrylate (EEgMA) were polymerized and copolymerized with ethyl methacrylate (EMA) in a wide range of feed composition by bulk at high conversion. Glass transition temperature (T_g) increased with the content of EgMA in the copolymer whereas T_g decreased with the content of EEgMA. The presence of any of the eugenyl monomers in the copolymer increased the thermal stability of the materials. Rheological analysis showed that EMA-co-EgMA copolymers present a higher density of crosslinking or entanglements among the chains compared with EMA-co-EEgMA materials, and copolymers containing more than 40% EgMA exhibited a pseudo-solid like behaviour with G′ relatively independent of the frequency. The average molecular weight between cross-links (M_c) for the latter copolymers was in the order of 10⁴ Da. For EEgMA copolymers, tan δ was lower than unity and G′ showed a gradual and slight dependency with frequency over the whole range of composition. In vitro behaviour showed a higher hydrophilicity of the EEgMA containing copolymers manifested in higher water sorption values, lower water contact angle values and higher surface free energy due to an increase in polarity. All systems presented a good cytocompatibility with human fibroblasts assessed through direct and indirect assays.     

Age-Related Changes in the Matrisome of the Mouse Skeletal Muscle

Aging is characterized by a progressive decline of skeletal muscle (SM) mass and strength which may lead to sarcopenia in older persons. To date, a limited number of studies have been performed in the old SM looking at the whole, complex network of the extracellular matrix (i.e., matrisome) and its aging-associated changes. In this study, skeletal muscle proteins were isolated from whole gastrocnemius muscles of adult (12 mo.) and old (24 mo.) mice using three sequential extractions, each one analyzed by liquid chromatography with tandem mass spectrometry. Muscle sections were investigated using fluorescence- and transmission electron microscopy. This study provided the first characterization of the matrisome in the old SM demonstrating several statistically significantly increased matrisome proteins in the old vs. adult SM. Several proteomic findings were confirmed and expanded by morphological data. The current findings shed new light on the mutually cooperative interplay between cells and the extracellular environment in the aging SM. These data open the door for a better understanding of the mechanisms modulating myocellular behavior in aging (e.g., by altering mechano-sensing stimuli as well as signaling pathways) and their contribution to age-dependent muscle dysfunction.