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We undertook a qualitative e-mail survey of federally-funded principal investigators of their views of the US human subjects protection system, intended to identify the range of investigator attitudes. This was an exploratory study with a 14% response rate. Twenty-eight principal investigators responded; their comments were analyzed to show underlying themes, which are here presented along with supporting quotations. There was consensus that it is important to protect human subjects from research abuse, but disagreement over how well the IRB system is functioning. Some researchers felt that the system is effective and serves its purpose well. Of those who support the system, some endorse its methods, purpose, and daily functioning, as they experience it, without reservation. Others, while expressing some frustration, feel that the purpose is important and their local IRB does its best to make a difficult system work well. Those investigators who were more harshly critical commented on multiple flaws in the system, including (1) consent forms that are inappropriate and incomprehensible, (2) an emphasis on minutiae, and (3) concern with protecting the institution more than research subjects. Respondents told us that the IRB system is a particular burden for research in neurology, emergency medical conditions, repositories, and social sciences in general; a more comprehensive study might identify other problematic areas. Significant concern was expressed about the cost, inefficiency, and irrationality of IRB review. The IRB system works well for some researchers, but our results indicate that other investigators feel the costs outweigh the benefits.

The purpose of the study was to investigate molecular changes associated with glioma tissues using Fr-IR microspectroscopic imaging (Fr-IRM). A multivariate statistical analysis allowed one to successfully discriminate between normal, tumoral, peri-tumoral, and necrotic tissue structures. Structural changes were mainly related to qualitative and quantitative changes in lipid content, proteins, and nucleic acids that can be used as spectroscopic markers for this pathology. We have developed a spectroscopic model of glioma to quantify these chemical changes. The model constructed includes individual FT-IR spectra of normal and glioma brain constituents such as lipids, DNA, and proteins (measured on delipidized tissue). Modeling of FT-IR spectra yielded fit coefficients reflecting the chemical changes associated with a tumor. Our results demonstrate the ability of FT-IRM to assess the importance and distribution of each individual constituent and its variation in normal brain structures as well as in the different pathological states of glioma. We demonstrated that (i) cholesterol and phosphatidylethanolamine contributions are highest in corpus callosum and anterior commissure but decrease gradually towards the cortex surface as well as in the tumor, (ii) phosphatidylcholine contribution is highest in the cortex and decreases in the tumor, (iii) galactocerebroside is localized only in white, but not in gray matter, and decreases in the vital tumor region while the necrosis area shows a higher concentration of this cerebroside, (iv) DNA and oleic acid increase in the tumor as compared to gray matter. This approach could, in the future, contribute to enhance diagnostic accuracy, improve the grading, prognosis, and play a vital role in therapeutic strategy and monitoring.

BackgroundAimsMethods & proceduresOutcomes & resultsConclusionsTense production is often impaired in people with aphasia (PWA). Interestingly, the literature suggests that not all tenses are affected in the same way, although the pattern of dissociation is still debated in the literature. The heterogeneity of tense production deficits in PWA might partly explain this lack of consensus in the literature. While this heterogeneity has been demonstrated by descriptive statistics or double dissociations in several studies, no study has used cluster analyses to highlight the main patterns of tense dissociation. Furthermore, the factors underlying this heterogeneity have been little explored.Our study aimed to use cluster analyses on tense production performance to (1) identify the main patterns of dissociation between tenses in PWA and (2) explore the clinical (aphasia type and severity) and cognitive (executive disorders and temporality) factors that may underlie these patterns.Twenty-one French-speaking participants with fluent and non-fluent aphasia completed a verb inflection production task, as well as language and cognitive tests. Cluster analyses were performed on the differences in performance between the tenses on the verb inflection production task. Generalized linear mixed models and nonparametric statistics were used to analyze the effect of tense and its interaction with the clusters, and to compare the clusters on the clinical and cognitive variables.Cluster analyses revealed two main clusters, one with worse performances in the past and future than in the present (PWA_1 – 70% of the PWA), and the other with worse performances in the past and present than in the future (PWA_2 – 30%). The type and severity of aphasia, and cognitive test performance did not differ between the two clusters. On the other hand, the PWA_2 cluster had a longer time post-onset than the PWA_1 cluster.Our results confirm the heterogeneity of verb inflection deficits in PWA. They suggest that most PWA would have difficulties with past and future tenses, questioning the presence of discourse linking in these two tenses. However, a minority of PWA, who are clinically and cognitively indistinguishable from the others, do not follow this pattern. Adopting the strategy of producing a morphologically simple tense in French – future – could explain the high performance in the future tense and the errors in substituting other tenses with the future in this subgroup. Finally, the clinical and research implications of this heterogeneity, in relation to therapies and the lack of consensus in the literature, are discussed. [ABSTRACT FROM AUTHOR]

Theories of speech production suggest that phonetic encoding involves an access to stored syllable-sized articulatory plans. Both neurolinguistic and psycholinguistic investigations have reported an effect of the frequency of use of syllabic units, respectively on accuracy and errors in brain-damaged (BD) speakers and on production latencies in nonbrain-damaged speakers. Beyond these convergent results, the fact that the same effects have been reported with BD patients with and without impairment ascribed at the level of phonetic encoding challenges the architecture of speech production models and the interpretation of patients' behaviour. Here we carry out a fully parallel neurolinguistic and psycholinguistic investigation to address whether previous diverging results can be accounted for by methodological differences between neurolinguistic and psycholinguistic studies. We analysed production accuracy in 14 BD speakers and production latencies in 24 non brain-damaged speakers using the same pseudoword stimuli, same reading and repetition tasks, and same multiple regression approach. Results replicate evidence from previous neurolinguistic and psycholinguistic studies on an influence of syllable frequency independently of other sublexical variables in both populations. In addition, the effect of syllable frequency on production accuracy was not limited to BD patients with impaired phonetic encoding. We suggest that these results are best accounted for by postulating interaction between phonological and phonetic encoding. [ABSTRACT FROM AUTHOR]