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Over 36 million people worldwide are infected with HIV. Antiretroviral therapy (ART) has proven to be highly effective to prevent HIV-1 transmission, clinical progression and death. Despite this success, the number of HIV-1 infected individuals continues increasing and ART should be taken for life. Therefore, there are two main priorities: the development of preventive vaccines to protect from HIV acquisition and achieve an efficient control of HIV infection in the absence of ART (functional cure). In this sense, in the last few years, there has been a broad interest in new and innovative approaches such as mRNA-based vaccines. RNA-based immunogens represent a promising alternative to conventional vaccines because of their high potency, capacity for rapid development and potential for low-cost manufacture and safe administration. Some mRNA-based vaccines platforms against infectious diseases have demonstrated encouraging results in animal models and humans. However, their application is still limited because the instability and inefficient in vivo delivery of mRNA. Immunogens, design, immunogenicity, chemical modifications on the molecule or the vaccine delivery methods are all crucial interventions for improvement. In this review we, will present the current knowledge and challenges in this research field. mRNA vaccines hold great promises as part of a combined strategy, for achieving HIV functional cure.  相似文献   
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Multiple trauma is often associated with blunt thoracic injuries. Especially lung contusion can result in respiratory insufficiency and therefore a higher mortality rate. In our prospective study comparing 8 multiple trauma patients with and without associated lung contusion, we found that respiratory function was already significantly disturbed (decrease of paO2/FiO2 and increase of AaDO2, a rise in extravascular lung water (EVLW) both early after trauma and also with a second peak following the 4th day. This group (LK) developed significantly more cases of respiratory distress (ARDS). The disturbance of respiratory function seen initially was interpreted as a consequence of the direct mechanical impact, leading to the formation of interstitial fluid and hematoma. The frequent development of ARDS in the LK-group probably results from a pronounced activation of cellular and humoral mechanisms and therefore an enforced injury of the pulmonary capillary bed. A significant increase of pulmonary infections or the development of sepsis was not seen in the LK-group and is probably not responsible for the higher ARDS-rate in this group.  相似文献   
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BACKGROUND AND PURPOSE: The efficacy of radiation treatment (RT) for plantar heel pain has been reported repeatedly. Yet, the results referring to the pain relief rate, to long-term effects and prognostic factors are not consistent. In this paper, the effectiveness (pain relief rate and long-term results) and prognostic factors of RT for plantar heel pain have been investigated. PATIENTS AND METHODS: From January 2000 to October 2000, 62 patients (73 heels) with painful plantar heel spurs and a minimum pain history of 3 months were treated and evaluated in a prospective study. Mean age was 54 years (range 28-84 years). All patients were treated with a total dose of 5 Gy in seven fractions (= one series), given twice a week at a single-dose sequence of 0.25-0.25-0.5-1.0-1.0-1.0-1.0 Gy (10-MV photons, source-skin distance [SSD] 100 cm, direct portal, field size 12 x 17 cm). The mean duration of heel pain before RT was 26 weeks (= 6.5 months; range 3-120 months). By means of a visual analog scale (VAS) the patients had to self-assess the quantity of their heel pain once before, three times during and four times after RT at a longterm median follow-up of 28 and 40 months. Additionally, the patients had to assess their mechanical heel stress extent during RT. Effectiveness was estimated according to the patients' judgment of pain reduction. RESULTS: A significant reduction of heel pain extent measured by VAS has been observed already during the RT series (before RT: 6.3 +/- 1.5 vs. 3.8 +/- 2.1 at the end of RT; p < 0.001). 6 weeks after RT (FU 1) pain reduction (> 20%) was achieved in 60 heels (82.3%; n = 73), in 64 heels (91.4%; n = 70) after a mean follow-up of 28 months (FU 2), and in 61 heels (89.7%; n = 68) after a mean follow-up of 40 months (FU 3), respectively. Sufficient pain relief (> 80% compared to initial extent) was observed in 18/73 heels (24.6%) at FU 1 (FU 2: 42/70; 60.0%; FU 3: 37/68; 54.4%), including 13/73 heels (17.8%) with complete pain relief (FU 2: 39/70; 55.7%; FU 3: 36/68; 52.9%). Partial improvement (50-80% pain reduction) was observed in 27/73 heels (37.0%) at FU 1 (FU 2: 14/70; 20.0%; FU 3: 15/68; 22.1%), and minor partial improvement (20-50% pain reduction) in 15/73 heels (20.5%) at FU 1 (FU 2: 8/70; 11.4%; FU 3: 9/68; 13.2%), respectively. No change was seen in 13/73 heels (17.8%) at FU 1 (FU 2: 6/70; 8.6%; FU 3: 7/68; 10.3%). Older patients (p = 0.04) and patients who avoided heel stress during the period of RT (p < 0.01) demonstrated a better short-term response (FU 1); both effects were lost 28 and 40 months after RT. Moreover, significant differences in the extent of heel pain reduction by RT were observed in dependence on previous pain duration (at FU 2-3). CONCLUSION: The results confirm the high efficacy of RT in painful plantar spur and add new aspects to formerly published data concerning the time course of changes in heel pain reduction. Pain relief can be expected during and shortly after RT. In addition, the initial success can be transformed into effective long-term results > 2 years after RT; however, further improvement is not to be expected. As a new prognostic factor, the reduction of mechanical heel stress during RT may ameliorate the short-term results, whereas short heel pain history improves the long-term results. Especially for older patients, RT should be taken into consideration as primary treatment.  相似文献   
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背景:非选择性β受体阻断剂能够降低门静脉压力和预防静脉曲张出血,但其能否预防静脉血管曲张尚不清楚。方法:对213例肝硬化门静脉高压患者犤最小门静脉压力梯度(H VPG)为6m m H g犦进行随机分组:其中108例接受噻吗洛尔(一种非选择性β受体阻断剂)治疗,105例接受安慰剂治疗。主  相似文献   
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