Assessment of Mendelian and risk-factor genes in Alzheimer disease: A prospective nationwide clinical utility study and recommendations for genetic screening

PURPOSE

To assess the likely pathogenic/pathogenic (LP/P) variants rates in Mendelian dementia genes and the moderate-to-strong risk factors rates in patients with Alzheimer disease (AD).

METHODS

We included 700 patients in a prospective study and performed exome sequencing. A panel of 28 Mendelian and 6 risk-factor genes was interpreted and returned to patients. We built a framework for risk variant interpretation and risk gradation and assessed the detection rates among early-onset AD (EOAD, age of onset (AOO) ≤65 years, n = 608) depending on AOO and pedigree structure and late-onset AD (66 < AOO < 75, n = 92).

RESULTS

Twenty-one patients carried a LP/P variant in a Mendelian gene (all with EOAD, 3.4%), 20 of 21 affected APP, PSEN1, or PSEN2. LP/P variant detection rates in EOAD ranged from 1.7% to 11.6% based on AOO and pedigree structure. Risk factors were found in 69.5% of the remaining 679 patients, including 83 (12.2%) being heterozygotes for rare risk variants, in decreasing order of frequency, in TREM2, ABCA7, ATP8B4, SORL1, and ABCA1, including 5 heterozygotes for multiple rare risk variants, suggesting non-monogenic inheritance, even in some autosomal-dominant-like pedigrees.

CONCLUSION

We suggest that genetic screening should be proposed to all EOAD patients and should no longer be prioritized based on pedigree structure.

Neuroimaging determinants of cognitive impairment in the memory clinic: how important is the vascular burden?

While neurodegenerative and vascular neurocognitive disorder (NCD) often co-occur, the contribution of vascular lesions, especially stroke lesions identified on MRI, to global cognition in a real-life memory clinic population remains unclear. The main objective of this retrospective study was to determine NCD neuroimaging correlates: the GM atrophy pattern and vascular lesions (especially stroke lesion localization by voxel-based lesion-symptom mapping, VLSM) in a memory clinic. We included 336 patients with mild or major NCD who underwent cerebral MRI and a neuropsychological assessment. The GM atrophy pattern (obtained by voxel-based morphometry, VBM) and the stroke lesion localization (obtained by VLSM) associated with G5 z-score (a global cognitive score), were included as independent variables with other neuroimaging and clinical indices in a stepwise linear regression model. The mean age was 70.3 years and the mean MMSE score 21.3. On MRI, 75 patients had at least one stroke lesion. The G 5 z-score was associated with GM density in the pattern selected by the VBM analysis (R2 variation = 0.166, p < 0.001) and the presence of a stroke lesion in the region selected by the VSLM analysis (mainly in the right frontal region; R2 variation = 0.018, p = 0.008). The interaction between the two factors was insignificant (p = 0.374). In conclusion, in this first study combining VBM and VLSM analysis in a memory clinic, global cognition was associated with a specific GM atrophy pattern and the presence of a stroke lesion mainly in the right frontal region.

The collaborative roles of stakeholders in supporting the adoption of sustainability in SMEs

There is growing concern among governments around the world about the need to enhance the social and environmental performance of small and medium enterprises (SMEs), seen as key actors in efforts to achieve national sustainability goals. However, despite efforts made to promote their role in this area, SMEs still struggle to integrate social and environmental concerns into their business practices. Barriers that impede the integration of sustainable development in SMEs include a limited awareness of the impacts and benefits associated with sustainability, a lack of time and resources, and a lack of skills and expertise. The aims of this study are to examine the key collaborative roles that a range of stakeholders can play to support sustainability adoption in SMEs and to understand how these roles contribute to overcoming barriers to adoption. Building on thirteen case studies, this study found that stakeholders play five different and complementary collaborative roles in supporting sustainability practices within SMEs, namely that of trainer, analyst, coordinator, specialist, and financial provider. The study shows that these five roles can be performed by a wide range of local stakeholders and can contribute to overcoming different barriers to the integration of sustainability practices within SMEs. These findings demonstrate that one key way for governments to improve the sustainability performance of SMEs may be to facilitate and shape the development of stakeholder networks capable of performing these five critical roles as part of efforts to promote sustainability adoption within firms.

Genetically encoded fluorescent sensors of membrane potential

Imaging activity of neurons in intact brain tissue was conceived several decades ago and, after many years of development, voltage-sensitive dyes now offer the highest spatial and temporal resolution for imaging neuronal functions in the living brain. Further progress in this field is expected from the emergent development of genetically encoded fluorescent sensors of membrane potential. These fluorescent protein (FP) voltage sensors overcome the drawbacks of organic voltage sensitive dyes such as non-specificity of cell staining and the low accessibility of the dye to some cell types. In a transgenic animal, a genetically encoded sensor could in principle be expressed specifically in any cell type and would have the advantage of staining only the cell population determined by the specificity of the promoter used to drive expression. Here we critically review the current status of these developments.

Violating ethics: unlawful combatants, national security and health professionals

Violations of ethical conduct

Errors in emergency physician interpretation of ST-segment elevation in emergency department chest pain patients

OBJECTIVE

To determine the rate of error in emergency physician (EP) interpretation of the cause of electrocardiographic (ECG) ST-segment elevation (STE) in adult chest pain patients.

METHODS

The authors conducted a retrospective ECG review of adult chest pain patients in a university hospital emergency department (ED) over a three-month period (January 1 to March 31, 1996). ST-segment elevation was determined to be present if the ST segment was elevated >/=1 mm in the limb leads and >/=2 mm in the precordial leads in at least two anatomically contiguous leads. Initial EP ECG interpretation was compared with the final interpretation by a cardiologist supported by the results of various clinical investigations. The rate of incorrect ECG diagnosis was calculated.

RESULTS

Two hundred two patients had STEs. The rate of ECG STE misinterpretation was 12 of 202 (5.9%). The most frequently misdiagnosed form of STE was left ventricular aneurysm, for which two of five cases were believed to represent acute myocardial infarction (AMI). The benign early repolarization (BER) pattern was the second most frequently misinterpreted STE entity-in a total of three cases, two were initially noted to represent pericarditis and one AMI. ST-segment elevation resulting from actual AMI was initially incorrectly noted to be noninfarction in etiology in two cases, one patient with BER and the other with left ventricular hypertrophy.

CONCLUSIONS

Emergency physicians show a low rate of ECG misinterpretation in the patient with chest pain and STE. The clinical consequences of this misinterpretation are minimal.

Neuropeptide Y-induced contraction is mediated by neuropeptide Y Y2 and Y4 receptors in the rat colon

Ascending and descending segments of the rat colon were studied to analyze their contractile responses to neuropeptide Y and related peptides. These responses are (a) completely eliminated by tetrodotoxin (1 microM), (b) reduced to a variable extent (20 to 60%) by atropine (1 microM) and (c) not modified by indomethacin, diphenhydramine or methysergide. The order of potency of agonists for peptides related to neuropeptide Y was as follows: human pancreatic polypeptide = rat pancreatic polypeptide > peptide YY = peptide YY-(3-36) = [Leu31,Pro34]neuropeptide Y > neuropeptide Y-(2-36) > C2-neuropeptide Y = neuropeptide Y > neuropeptide Y-(13-36), with minor differences observed between the two parts of the colon. This selectivity pattern does not correspond to the profile of any known cloned neuropeptide Y receptors. BIBP3226, a selective antagonist for the neuropeptide Y Y1 receptor sub-type, was found to be inactive, while a neuropeptide Y Y2 receptor antagonist, T4-[NPY-(33-36)]4, reduced the effects of neuropeptide Y, peptide YY, peptide YY-(3-36) and C2-neuropeptide Y without affecting those of human pancreatic polypeptide, rat pancreatic polypeptide and [Leu31,Pro34]neuropeptide Y. JCF 104 (compound 28), a putative neuropeptide Y Y5 receptor antagonist, showed no effect or a weak inhibition of human pancreatic polypeptide or [Leu31,Pro34]neuropeptide Y-induced contraction. Taken together, these data suggest that: (1) at least two neuropeptide Y receptor types are present in the rat colon autonomic nerve terminals and modulate the release of acetylcholine and possibly other transmitters; (2) a proportion of the receptors mediating the contractile response of the rat colon (especially descending part) to neuropeptide Y and related peptides appears to be of the Y2 type and (3) the significant portion of the response is mediated by a receptor which is insensitive to neuropeptide Y Y1, Y2 and to neuropeptide Y Y5 receptor antagonists. This receptor behaves as a neuropeptide Y Y4 receptor sub-type and appears to be located on enteric nerves.

Accumulation of an acidic dehydrin in the vicinity of the plasma membrane during cold acclimation of wheat

Expression of the acidic dehydrin gene wcor410 was found to be associated with the development of freezing tolerance in several Gramineae species. This gene is part of a family of three homologous members, wcor410, wcor410b, and wcor410c, that have been mapped to the long arms of the homologous group 6 chromosomes of hexaploid wheat. To gain insight into the function of this gene family, antibodies were raised against the WCOR410 protein and affinity purified to eliminate cross-reactivity with the WCS120 dehydrin-like protein of wheat. Protein gel blot analyses showed that the accumulation of WCOR410 proteins correlates well with the capacity of each cultivar to cold acclimate and develop freezing tolerance. Immunoelectron microscope analyses revealed that these proteins accumulate in the vicinity of the plasma membrane of cells in the sensitive vascular transition area where freeze-induced dehydration is likely to be more severe. Biochemical fractionation experiments indicated that WCOR410 is a peripheral protein and not an integral membrane protein. These results provide direct evidence that a subtype of the dehydrin family accumulates near the plasma membrane. The properties, abundance, and localization of these proteins suggest that they are involved in the cryoprotection of the plasma membrane against freezing or dehydration stress. We propose that WCOR410 plays a role in preventing the destabilization of the plasma membrane that occurs during dehydrative conditions.

Accumulation of an acidic dehydrin in the vicinity of the plasma membrane during cold acclimation of wheat

Expression of the acidic dehydrin gene wcor410 was found to be associated with the development of freezing tolerance in several Gramineae species. This gene is part of a family of three homologous members, wcor410, wcor410b, and wcor410c, that have been mapped to the long arms of the homologous group 6 chromosomes of hexaploid wheat. To gain insight into the function of this gene family, antibodies were raised against the WCOR410 protein and affinity purified to eliminate cross-reactivity with the WCS120 dehydrin-like protein of wheat. Protein gel blot analyses showed that the accumulation of WCOR410 proteins correlates well with the capacity of each cultivar to cold acclimate and develop freezing tolerance. Immunoelectron microscope analyses revealed that these proteins accumulate in the vicinity of the plasma membrane of cells in the sensitive vascular transition area where freeze-induced dehydration is likely to be more severe. Biochemical fractionation experiments indicated that WCOR410 is a peripheral protein and not an integral membrane protein. These results provide direct evidence that a subtype of the dehydrin family accumulates near the plasma membrane. The properties, abundance, and localization of these proteins suggest that they are involved in the cryoprotection of the plasma membrane against freezing or dehydration stress. We propose that WCOR410 plays a role in preventing the destabilization of the plasma membrane that occurs during dehydrative conditions.

The evaluation of Franco-Quebec victims of child sexual abuse and their mothers: the implementation of a standard assessment protocol

OBJECTIVE

There were two aims: first, to evaluate the feasibility of applying a standard assessment protocol to Franco-Quebec victims of child sexual abuse and nonoffending mothers; and second, to compare results from an initial sample with available data from English-speaking samples.

METHOD

A standard individual case study design was used for victims and mothers; and the satisfaction of the nine participating youth workers was assessed. Four self-report instruments for victims and five for mothers were chosen on the bases of workers' priorities, sensitivity to the impact of CSA, and the availability of published norms on English-speaking samples. Results are reported on 48 confirmed victims and 40 nonoffending mothers.

RESULTS

The protocol was favorably received by the CPS workers, supervisors and all mothers and victims. Percentages of clinically distressed victims varied from highs of 68% on the externalization difficulties of the Child Behavior Checklist and 67% for 2- to 6-year-olds on the Child Sexual Behavior Inventory, to lows of 10% on hostility symptoms and 13% on the Dissociation Scale of the Trauma Symptom Check for Children. The rate of symptom-free children was lower (19%) and that of revictimization higher (30%) than most published estimates (Kendall-Tackett, Williams, & Finkelhor, 1993). Most mothers reported elevated emotional distress (depression, 59%) and symptoms of post-traumatic stress (intrusiveness, 67%). Although 87% of mothers believed the allegations, only 45% offered adequate emotional support.

CONCLUSION

The implementation phase of this research was successful, given the positive reactions of workers and clients. Results on standard instruments from this French-speaking sample were similar to profiles of English-speaking victims and their mothers but firm conclusions on appropriate norms will require larger samples, cross cultural contrasts, and the evaluation of additional variables.