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We present evidence from neutron diffraction measurements and molecular dynamics (MD) simulations of three different monolayer phases of the intermediate-length alkanes tetracosane (n-C24H50 denoted as C24) and dotriacontane (n-C32H66 denoted as C32) adsorbed on a graphite basal-plane surface. Our measurements indicate that the two monolayer films differ principally in the transition temperatures between phases. At the lowest temperatures, both C24 and C32 form a crystalline monolayer phase with a rectangular-centered (RC) structure. The two sublattices of the RC structure each consists of parallel rows of molecules in their all-trans conformation aligned with their long axis parallel to the surface and forming so-called lamellas of width approximately equal to the all-trans length of the molecule. The RC structure is uniaxially commensurate with the graphite surface in its [110] direction such that the distance between molecular rows in a lamella is 4.26 Å=3ag, where ag=2.46 Å is the lattice constant of the graphite basal plane. Molecules in adjacent rows of a lamella alternate in orientation between the carbon skeletal plane being parallel and perpendicular to the graphite surface. Upon heating, the crystalline monolayers transform to a “smectic” phase in which the inter-row spacing within a lamella expands by ∼10% and the molecules are predominantly oriented with the carbon skeletal plane parallel to the graphite surface. In the smectic phase, the MD simulations show evidence of broadening of the lamella boundaries as a result of molecules diffusing parallel to their long axis. At still higher temperatures, they indicate that the introduction of gauche defects into the alkane chains drives a melting transition to a monolayer fluid phase as reported previously. [ABSTRACT FROM AUTHOR]

Weiss G, Meyer F, Matthies B, et al. Br J Nutr 2002;87:S89-S94. It has been increasingly reported that administration of n-3 fatty acids is beneficial in patients with inflammatory processes. [...]

Endovascular repair of AAA's using stent grafts is considered to be a minimally invasive procedure. However, in some cases deleterious inflammatory reactions, e.g., flu-like postinterventional symptoms are observed. A few patients even develop a fatal "postimplantation syndrome". It is not clear whether these postoperative complications result from a) the inflammatory and immune response to the inserted graft material, b) alterations of the vascular endothelium during the implantation procedure, c) residual thrombotic material, or d) a combination of all these causes. This clinical trial aimed to prospectively investigate the association between inflammatory mediators like interleukin-1 receptor antagonist (IL-1RA), IL-6, and HLA-DR expression on monocytes and clinical outcome in patients after repair of abdominal aortic aneurysms (AAA). Fifteen patients treated with endovascular stent grafts for abdominal aortic aneurysm (AAA-E) were compared with 15 selected control patients who underwent a conventional surgical procedure (AAA-K) during the same period. Prior to intervention, there were no significant differences in marker levels. One hour postoperatively, IL-6 (421 pg/ml vs. 21 pg/ml) and IL-1RA (10,061 pg/ml versus 407 pg/ml) were significantly increased in the AAA-K-group, whereas in AAA-E patients, these parameters increased more gradually during the first postoperative day and did not reach the same level as in the control group. There was only a slight reduction of HLA-DR expression in both groups compared with baseline and no signs indicating a postimplantation syndrome were found. No excessive inflammatory response or complicated final outcome were observed. It is unclear if this can be explained by the prophylactic use of indometacin.

Objectives: To determine the efficacy of methylphenidate in improving attention and functional outcome in acutely brain-injured adults., Design: Prospective multiple baseline design (A-A-B-A) utilized on a consecutive sample of patients., Setting: Acute brain injury rehabilitation unit in a large academic medical center., Patients: Eleven acutely brain-injured adults were included by performing below two standard deviations of the age equivalent norms on 4 of 5 neuropsychological tests for attentional capacity. One subject was withdrawn after developing tachycardia., Intervention: After a 1-week baseline assessment, subjects were placed on increasing doses of methylphenidate (Ritalin) so that on Day 7 all patients received a dose of 15 mg at 8 am and 12 pm., Main Outcome Measures: Nine neuropsychological subtests measured attention on admission, at 1 week, while on methylphenidate, and 1 week after its discontinuation. Functional outcome was evaluated utilizing the Disability Rating Scale (DRS) at the same intervals., Results: Digit Span, Mental Control, and Symbol Search scores improved significantly (p < .05) on methylphenidate (A-B) as compared with the pre-methylphenidate (A-A) period. This advantage remained when the drug was removed. The mean improvement in DRS scores on methylphenidate approached a significant difference (p < .06) from that change in the DRS scores between baseline 1 and 2., Conclusions: Use of methylphenidate in acutely brain-injured adults was well tolerated and demonstrated a significant improvement in attention compared to natural recovery in a rehabilitation setting. Methylphenidate also correlated with faster functional recovery as measured by the Disability Rating Scale although the improvement did not achieve statistical significance.

This paper outlines general management strategies used to prevent and control agitation throughout the continuum of recovery from traumatic brain injury. These include environmental management, alterations in the behavior of staff and family, use of physical and chemical restraints, redirection and substitution, time out, operant procedures, self monitoring and relaxation training. The need for both flexibility in choice of strategies and consistency in application is emphasized, along with the importance of staff training and patient and family participation.