Reviews of Functional MRI: The Ethical Dimensions of Methodological Critique

Neuroimaging studies involving human subjects raise a range of ethics issues. Many of these issues are heightened in the context of neuroimaging research involving persons with mental health disorders. There has been growing interest in these issues among legal scholars, philosophers, social scientists, and as well as neuroimagers over the last decade. Less clear, however, is the extent to which members of the neuroimaging community are engaged with these issues when they undertake their research and report results. In this study, we analyze the peer-reviewed review literature involving fMRI as applied to the study of mental health disorders. Our hypothesis is that, due to the critical orientation of reviews, and the vulnerability of mental health population, the penetrance of neuroethics will be higher in the review literature in this area than it is in the primary fMRI research literature more generally. We find that while authors of reviews do focus a great deal of attention on the methodological limitations of the studies they discussed, contrary to our hypothesis, they do not frame concerns in ethical terms despite their ethical significance. We argue that an ethics lens on such discussion would increase the knowledge-value of this scholarly work.     

X-linked adrenoleukodystrophy phenotype is independent of ABCD2 genotype

Strikingly variable clinical phenotypes can be found in X-linked adrenoleukodystrophy (X-ALD) even with the same ABCD1 mutation. ABCD2 is the closest homolog to ABCD1. Since ABCD2 overexpression complements the loss of ABCD1 in vivo and in vitro, we have investigated the possible role of the ABCD2 gene locus as determinant of X-ALD phenotypes. Sequence and segregation analysis of the ABCD2 gene, in a large X-ALD family with different phenotypes disclosed that the identical ABCD2 alleles were inherited in brothers affected by mild (noncerebral) versus severe (childhood cerebral) X-ALD phenotypes. Moreover, two independent association studies of ABCD2 polymorphisms and clinical phenotypes showed an even allele distribution in different X-ALD phenotypes and controls. Based on these findings ABCD2 can be excluded as a major modifier locus for clinical diversity in X-ALD. These findings are of particular importance for the attempt of pharmacological induction of ABCD2 as a possible therapeutic approach in X-ALD.     

Ferric pyridoxal isonicotinol hydrazone can provide iron for heme synthesis in reticulocytes

We have examined whether reticulocytes depleted of transferrin might incorporate ⁵⁹Fe from ⁵⁹Fe-labelled pyridoxan isonicotinoyl hydrazone (PIH). Transferrin-depleted reticulocytes showed a time-, temperature- and concentration-dependent incorporation of ⁵⁹Fe when incubated with 20–200 μM ⁵⁹Fe-PIH. The amount of ⁵⁹Fe incorporated with 200 μM ⁵⁹Fe-PIH is equal to or higher than that taken up from transferrin at 20 μM ⁵⁹Fe concentration. After 60 min about 60% of the ⁵⁹Fe taken up by the cells is recovered in heme while the remainder is probably still bound to PIH. 1 mM succinyl acetone (a specific inhibitor of heme synthesis) inhibits PIH-mediated incorporation of ⁵⁹Fe into heme by about 79% indicating that ⁵⁹Fe from ⁵⁹Fe-PIH is incorporated into de novo synthesized protoporphyrin. As is the case with transferrin, erythrocytes do not incorporate ⁵⁹Fe from ⁵⁹Fe-PIH. Pretreatment of reticulocytes with pronase does not inhibit their ability to incorporate ⁵⁹Fe from ⁵⁹Fe-PIH, suggesting that, unlike the uptake of Fe from transferrin, membrane receptors are not involved in the uptake of Fe-PIH by the cells.     

Comparison between in vitro potency tests for Cuban hepatitis B vaccine: contribution to the standardization process.

Quality control of recombinant Hepatitis B vaccines performed by National Control Laboratories prior to marketing vaccine batches requires in vivo and or a well validated in vitro potency assays as recommended by WHO technical series. The in vitro test must also demonstrate its suitability for monitoring the consistency of the vaccine manufacturer. The aim of this study was to establish the relationship between both in vitro potency tests performed by Cuban manufacturer and National Control Laboratory for Hepatitis B vaccine and the suitability of our method for monitoring the manufacturer's test results and consistency. We also intended to contribute to the standardisation process consisting of in vitro methods for this vaccine.