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The structures of Nafion membranes prepared by solutions casting from low aliphatic alcohols/water mixture solvents and N,N′‐dimethyl formamide (DMF) solvent were investigated using differential scanning calorimeter and small angle X‐ray scattering. The aggregation behavior of Nafion molecules in the casting solutions was also investigated using dynamic light scattering. We show that the morphology of membranes was strongly influenced by the conformations of Nafion molecules in the solutions. In aliphatic alcohol/water mixture solvents, which have a worse compatibility with Nafion backbones, the Nafion molecules aggregate and form fringed rod‐like structures. These primary rod‐like structures then aggregate again through fringed side chains to form secondary ionic aggregations. In DMF solvent, owing to its better compatibility with Nafion backbones, less Nafion molecules aggregate. The high degree of Nafion molecular aggregations in aliphatic alcohol/water mixture solvents leads to a high degree of hydrophobic and hydrophilic phase separation for membranes prepared by casting from Nafion/aliphatic alcohol/water solutions. However, the lower degree of molecular aggregations in DMF solvent results in a lower degree of hydrophobic and hydrophilic phase separation for membranes prepared by casting from Nafion/DMF solution. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3044–3057, 2005

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Objective. To analyze the clinical features and outcomes of patients with posterior reversible encephalopathy syndrome (PRES), the risk factors of PRES-related intracranial hemorrhage (ICH), and all-cause mortality in patients with systemic lupus erythematosus (SLE). Methods. Twenty-six episodes of PRES were identified in 23 SLE patients, using an electronic medical records database of 3,746 SLE patients.

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Study design: Cross-sectional study. Objective: To analyze the predictors of severe neurogenic bowel dysfunction (NBD) in persons with spinal cord injury (SCI). Setting: The Kaohsiung Medical University Hospital, Taiwan. Methods: Two questionnairesFthe NBD score and the Beck Depression Inventory second editionFwere sent to 232 persons with SCI by mail. The demographic factors and injury-related factors were recorded to evaluate any relationships with severe NBD. The associations between the severity of NBD and psychological condition were also measured. Results: In all, 39.4% of the respondents suffered from severe NBD. Multiple logistic regression analysis showed that those with a cervical injury (odds ratios (OR) ¼ 10.5, 95% confidence interval (CI) 1.6-67.7) or a thoracic injury (OR ¼ 7.1, 95% CI 1.2-40.3) had a higher risk of severe NBD than those with a lumbar injury. Persons with American Spinal Injury Association (ASIA) A had a 12.8-fold higher risk of severe NBD than persons with ASIA D (OR ¼ 12.8, 95% CI 3.3-50.1). Longer duration of injury (X10 years) was another risk factor of severe NBD. Moderate-to-severe depression was associated with reduced bowel function. Conclusions: This study showed that high level of cord lesion, completeness of cord injury and longer duration of injury (X10 years) could predict the severity of NBD in patients with SCI.

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The presynaptic terminal and axon of neurons can undergo structural changes in response to environmental signals. Since these changes require protein synthesis in the cell body, the needs of the periphery must somehow be communicated to the cell soma. To look for such a mechanism, we used artificial protein constructs with properties expected of a signal that is transported from the axon to the nucleus. One construct consisted of the nuclear import signal peptide (sp) of the SV40 large T antigen, coupled to human serum albumin (HSA) and rhodamine (r). When injected into the axoplasm of Aplysia californica neurons in vitro, the rHSA-sp was transported in the retrograde direction through the axon to the cell body and then into the nucleus. Little, if any, moved in the anterograde direction toward growth cones. The retrograde movement of injected rHSA-sp was rapid (greater than 25 mm/d) and depended upon intact microtubules. The sp portion of rHSA-sp provided access to both the retrograde transport system and the nuclear import apparatus. Thus, rHSA was not transported at all, but accumulated in organelles near the injection site. Also, rHSA-sp containing an sp with a Lys to Thr substitution, which is known to reduce nuclear import markedly, was transported only poorly. To look for endogenous molecules that use this system, we affinity-purified a rabbit polyclonal antibody to the signal sequence. The antibody recognized an 83 kDa polypeptide on Western blots of Aplysia nervous tissue. These data indicate that Aplysia neurons contain the machinery to convey macromolecules from the axon periphery to the nucleus.