Functional signatures of protective antiviral T-cell immunity in human virus infections

Summary: The most common human viruses have different abilities to establish persistent chronic infection. Virus‐specific T‐cell responses are critical in the control of virus replication and in the prevention of disease in chronic infection. A large number of phenotypic markers and a series of functions have been used to characterize virus‐specific CD4⁺ and CD8⁺ T‐cell responses, and these studies have shown great phenotypic and functional heterogeneity of the T‐cell responses against different viruses. The heterogeneity of the T‐cell response has been proposed to be specific to each virus. However, over the past 2 years, several studies have provided evidence that the phenotypic and functional heterogeneity of CD4⁺ and CD8⁺ T‐cell responses is predominantly regulated by the levels of antigen load. The levels of antigen load modulate the phenotypic and functional patterns of the T‐cell response within the same virus infection. Furthermore, the functional characterization of virus‐specific CD4⁺ and CD8⁺ T‐cell responses has identified signatures of protective antiviral immunity. Polyfunctional, i.e. interleukin‐2 and interferon‐γ (IFN‐γ) secretion and proliferation, and not monofunctional, i.e. IFN‐γ secretion, CD4⁺ and CD8⁺ T‐cell responses represent correlates of protective antiviral immunity in chronic virus infections.     

Treatment of Status Epilepticus in Adults: Guidelines of the Italian League Against Epilepsy

Summary:  Status epilepticus (SE) is a medical emergency which can lead to significant morbidity and mortality and requires prompt diagnosis and treatment. SE is differentiated into generalized or partial SE on the basis of its electro-clinical manifestations. The guidelines for the management of SE produced by the Italian League against Epilepsy also distinguish three different stages of SE (initial, established and refractory), based on time elapsed since the onset of the condition and responsiveness to previously administered drugs. Treatment should be started as soon as possible, particularly in generalized convulsive SE, and should include general support measures, drugs to suppress epileptic activity and, whenever possible, treatments aimed at relieving the underlying (causative) condition. Benzodiazepines are the first line antiepileptic agents, and i.v. lorazepam is generally preferred because it is associated with a lower risk of early relapses. If benzodiazepines fail to control seizures, i.v. phenytoin is usually indicated, though i.v. phenobarbital or i.v. valproate may also be considered. Refractory SE requires admission to an intensive care unit (ICU) to allow adequate monitoring and support of respiratory, metabolic and hemodynamic functions and cerebral electrical activity. In refractory SE, general anesthesia may be required. Propofol and thiopental represent first line agents in this setting, after careful assessment of potential risks and benefits.     

Age-related changes in the turnover rates of D1-dopamine receptors in the retina and in distinct areas of the rat brain

The steady-state density and the turnover rates of D₁-dopamine receptors were investigated in the striatum, nucleus accumbens, substantia nigra, and retina of adult (3-month-old) and aged (23-month-old) rats. The turnover rates were measured by monitoring the repopulation kinetics of D₁-dopamine receptors labeled with [³H]-SCH 23390 after the irreversible inactivation induced by a single dose of N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 10 mg/kg, s.c.). In all the neural tissues examined, the repopulation of D₁ dopamine receptors could be adequately described by a theoretical model that assumes a constant rate of receptor production (i.e. zero order) and a rate of degradation that is dependent on the receptor density at any time (i.e. first order). The results obtained indicate that the reduction in the density of D₁-dopamine receptors in the striatum, nucleus accumbens and substantia nigra of aged rats is the result of a larger decrease in the receptor production rate (−44 to −60%) than in the receptor degradation rate (−21 to −46%). By contrast, the production rate of D₁-dopamine receptors in the retina of aged rats remains unchanged, whilst the degradation rate is reduced by 25%. This results in an age-related increase in the density of D₁-dopamine receptors in the rat retina.     

未破裂脑动脉瘤的治疗选择

未破裂脑动脉瘤的处理存在争议。由于其自然史尚未完全明确,因此最佳的治疗策略也不清楚。目前对未破裂脑动脉瘤处理的共识包括观察、显微手术夹闭和血管内治疗。用于随访已知未破裂脑动脉瘤的方法学也有争议,可能取决于经治医生的偏好。大多数动脉瘤由神经外科医师和介入神经放射科医师处理,但未破裂动脉瘤通常是由神经科医师在对患者进行其他神经系统疾病的筛查时首先发现的。因此,关于何时对患者进行筛查和如何对未破裂动脉瘤采取最佳处理的知识将对其日常医疗实践有直接的影响。未破裂动脉瘤经常导致包括缺血事件、癫和头痛在内的其他神经系统症状,这些症状可能促进更积极的干预治疗。由于缺乏设计完善真正基于人群的研究或随机试验,因此目前的最佳处理必须以现有文献和每例患者当时的具体情况为根据。     

Poly(2,6-Dimethyl-1,4-Phenylene oxide)/crosslinked polystyrene semi-interpenetrating networks: Synthesis and properties

Semi-interpenetrating networks (semi-IPN's) based on linear poly(phenylene ether)s and crosslinked polystyrene can be prepared by reactive moulding of crosslinkable polymeric mixtures. These materials show thermomechanical properties which strongly depend on both the ratio of the two polymeric matrices and the degree of crosslinking in the polystyrene network. Samples based on a 50/50 weight ratio of poly(2,6-dimethyl-1,4-phenylene oxide)/crosslinked polystyrene show glass transition temperatures (T_g) which are very dependent on the degree of crosslinking. It is therefore possible to obtain materials with desired T_g, ranging from the T_g of the corresponding linear blend to that of poly(2,6-dimethyl-1,4-phenylene oxide) alone.