Interaction between APOE ɛ4 genotype and education on mild cognitive impairment

Introduction

Studies have identified the apolipoprotein E (APOE) ɛ4 genotype to be a genetic risk factor for mild cognitive impairment (MCI) with environmental factors, such as education, modifying this genetic effect. The aim of this study was to investigate possible interaction of APOE ɛ4 status and educational attainment on MCI.

Methods

Information on education, MCI and APOE status was available for 3,829 participants from the Heinz Nixdorf Recall study. Logistic regression models were fitted to estimate sex- and age-adjusted odds ratios (OR) and 95% confidence intervals (95%-CI) for education (<14 years vs. ≥14 years of education), APOE status (carrier vs. noncarrier) and the interaction between APOExeducation on multiplicative scale with MCI. To consider interaction on additive scale, the relative excess risk due to interaction (RERI) was calculated. The effect of APOE on MCI was additionally stratified by educational groups.

Results

A higher chance of MCI was observed for reporting <14 years of education (OR: 1.37 [95%-CI: 1.11, 1.69]) and having a positive APOE ɛ4 status (OR: 1.27 [95%-CI: 1.04, 1.55]). Stratified analysis showed a stronger genetic effect of APOE ɛ4 status on MCI in participants with low education (OR: 1.42 [95%-CI: 1.12, 1.79)], compared to participants with higher education (OR: 1.00 [95%-CI: 0.67, 1.45)]. An indication for positive interaction between education and APOE ɛ4 status on MCI was found on additive scale (RERI: 0.52 [95%-CI: 0.01, 1.03]), no interaction on the multiplicative scale was observed.

Conclusions

Results gave indication for positive interaction on the additive scale of APOE ɛ4 status and education, showing stronger genetic effects on MCI in groups of low education. Socioeconomically disadvantaged environments and health behaviors related to low educational attainment may be responsible for an altered APOE ɛ4 expression. Higher educated groups seem to be better equipped to reduce their genetic susceptibility for MCI.

Key messages

A descriptive study of a specialized worker's psychological trauma program

BACKGROUND

Psychological trauma in the workplace is gaining recognition as an important cause of workplace disability but little is known about the workers who are affected. The Psychological Trauma Program (PTP) in Toronto (Canada) is a specialized provincial worker's compensation board assessment program for workers with psychological sequelae of workplace trauma.

AIMS

To characterize workers presenting to the PTP in terms of demographic, occupational, traumatic exposure and diagnostic variables.

METHODS

A retrospective secondary analysis of all workers referred to the PTP for assessment within 1 year of traumatic event between 1999 and 2006.

RESULTS

Five hundred and thiry-one referred workers were included in the study. Most workers were working-age male (76%), married (65%) and labourers (43%). Nearly half were born outside Canada. Post-traumatic stress disorder was the primary diagnosis in 44%. Fifty-eight percent had one or more secondary diagnoses. For just over half of the workers, the traumatic event resulted in a permanent physical impairment.

CONCLUSIONS

Specialist referral may be indicated for workers experiencing prolonged recovery following workplace trauma. Male workers and those with co-morbidities or permanent injuries may be more likely to require referral. Individualized treatment approaches are likely important; however, more research is needed to guide future interventions.

Low-frequency distortion product otoacoustic emission test compared to ECoG in diagnosing endolymphatic hydrops

Previous studies assumed that specific audiometric measures like low-frequency biasing were noninvasive and inexpensive techniques for diagnosing endolymphatic hydrops (EH). The aim of this study was to compare the results of low-frequency DPOAE (LF-DPOAE) with those of transtympanic electrocochleography (ECoG) in patients with Menière's disease (MD). The prospective study included 50 patients, 22 to 72 years old, who were diagnosed with Menière's disease according to the criteria laid down by the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) in 1995. LF-DPOAE and ECoG were performed on the same day after standard audiometry. Enlarged amplitude of summation potential to action potential ratio was used as the diagnostic criterion for EH. The results were compared to those of LF-DPOAE. In this audiometric examination we used the modulation index (MI) to detect EH if MI < 0.5. ECoG yielded a result in 46 of the 50 patients examined. An enlarged SP/AP ratio was found in 23 patients (50%). The results of 33 patients could be compared, i.e. assessable results in both tests. The two tests yielded the same results in 13 patients and different ones in 20 patients. ROC analysis and Mann-Whitney statistics showed no significant correlation between the two tests. With ECoG as the gold standard for verifying EH, we found that LF-DPOAE is not yet a suitable method for diagnosing EH.

[Diagnosis of endolymphatic hydrops using low frequency modulated distortion product otoacoustic emissions]

BACKGROUND

The low frequency modulation of distortion product otoacoustic emissions (DPOAEs) is an objective audiometric method that appears to be a useful tool for the diagnosis of endolymphatic hydrops (EH), e.g. in patients with Menière's disease, or in those who present only some of the symptoms of the disease.

METHOD

Low-frequency modulated DPOAEs were registered in 20 patients with unilateral Menière's disease (13 women and 7 men, aged 40-66 years) and were compared to a control group matched in age and gender. As a diagnostic parameter, the 'modulation index' MI=1/2 MS/DM was used (MS or modulation span, being the difference between the maximal and the minimal DPOAE-amplitude, and DM, being the mean of the suppressed stationary DPOAE-amplitude).

RESULTS

In the patients with unilateral Menière's disease, MI was lower than in the control group. This difference was highly significant. In 56% of the patients' contralateral ears MI was lower than the cut off-value and significantly lower than in the control group, but did not differ significantly from the patients' ipsilateral ears.

CONCLUSION

The registration of low-frequency modulated DPOAEs is comparable to the generally applied transtympanic electrocochleography in its diagnostic validity. The method is fast and non-invasive and could be applied to monitor the course of the disease.

[Bipolar affective and schizoaffective disorders of older age -- classification, symptoms and course]

Bipolar affective and schizoaffective disorders of older age are underdiagnosed, although they are of growing importance for psychiatric services. In this review article, we present and discuss results concerning classification, psychopathology, epidemiology, course, prognosis, neuroimaging, family studies and therapy. Bipolar (schizo)affective disorders of older age are a diagnostic heterogeneous group, especially as secondary manias must be separated from "endogenous" bipolar disorders nosologically. Bipolar (schizo)affective disorders of older age show some peculiarities: Gender ratio, age at onset, mortality and comorbidity with neurological disease are amongst them. Nevertheless, in many other aspects bipolar (schizo)affective disorders of older age do not differ from bipolar disorders of younger patients. For the acute and maintenance treatment there is a dearth of controlled studies. Lithium is of great importance. Other substances, as well as psychoeducation and ECT may be used analogously as in younger patients, if age specific factors are taken into account (as for example the danger of falls).

Prevalence of Fungal Foot Infections in Patients with Diabetes Mellitus Type 1 - Underestimation of Moccasin-Type Tinea

In diabetic patients, mycotic infections may increase the risk of developing diabetic foot syndrome. However, few data are available on the prevalence of fungal foot infections in patients with diabetes. During a conference attended by patients with long-term diabetes, 95 individuals with type 1 diabetes mellitus (52 men, 43 women, mean disease duration 35.8 years) were examined for fungal infections of the feet. As well as frequency of infection and risk profiles, the level of patient awareness and preventive measures taken were assessed by means of a questionnaire. Clinically, 78 patients (82.1 %) showed probable pedal fungal infections, of which 84.6 % (66/78) were mycologically confirmed by direct microscopy and/or culture. Skin mycoses were found in 9 patients (toe webs 5, soles 4), onychomycosis in 29 patients and simultaneous infection of nails and skin in 28 patients (toe webs 8, soles 20). Thirty-seven (47.4 %) of these patients had positive cultures, particularly for the dermatophyte Trichophyton rubrum (69.2 % of isolates). A significant correlation was found between infection and gender (men more frequently affected) and the age of the patients. The actual frequency of mycoses was underestimated by the patients. This correlated with the assessment of their own knowledge level concerning fungal infections: 83.2 % of patients with skin mycoses and 88.4 % of those with onychomycosis of the feet felt that they needed more information about their disease. Marked mycoses on the soles were often considered to be dry skin by the patients. The high number of infections detected is especially remarkable in that this group of patients were highly motivated. It therefore appears that diabetics require more diagnostic, therapeutic and preventive care in terms of mycotic diseases than has been previously thought.

Phase-dependent suppression of transient evoked and distortion product otoacoustic emissions by a low-frequency tone

The subjective recording of the masked threshold of short acoustical stimuli with a loud tone of 30 Hz (phase audiogram) has been used for the clinical diagnosis of endolymphatic hydrops (EH). In normally-hearing subjects, a marked modulation of the threshold was found, depending on the phase of the low-frequency tone. A very small dependence was found in patients with Menière's disease, due to the micromechanical changes in the basilar membrane (BM). The same phase relationship becomes apparent in low-frequency suppression of otoacoustic emissions. The amplitudes of TEOAEs are controlled by the phase-dependent displacement of the BM. The suppressed TEOAEs have to be measured separately in each phase relationship. During recording of suppressed DPOAEs, the low-frequency suppressor is permanently superimposed on the pair of primary tones. After time averaging and a moving short-time FFT, the spectral values of the DPOAEs are obtained depending on the phase of the low-frequency tone. Modulation depends also on the masker level, the levels of the primary tones, and on their frequency range. The method of low-frequency suppressed DPOAEs is an objective method to diagnose EH and could be a useful tool in human inner ear research.

Low-frequency modulation of the 2f1-f2 distortion product otoacoustic emissions in the human ear

Low-frequency masking is a recent clinical procedure for the differential diagnosis of sensory hearing loss. Currently this requires the recording of the phase-dependent masked subjective threshold, which is time consuming and not always accurate. As an objective method, the recording of modulated distortion product otoacoustic emissions (DPOAEs) can be performed continuously, and with better frequency specificity. Results of measurements of the low-frequency modulated two-tone DPOAE 2f1-f2 in the human ear, and its dependence on various acoustic parameters, are presented here for the first time. Similar to the masked hearing threshold, the pattern of the phase-dependent modulated DPOAEs displayed two minima, at the phases of maximal rarefaction and condensation, respectively, with a latency of about 4 ms (suppressor frequency 32.8 Hz). The smaller dip, at maximal condensation, appeared only for a high suppressor level, and for a low level of the primary tone f2. The modulating effect measured for the primary frequencies f1 = 2.5 kHz and f2 = 3 kHz, decreased for 4 and 4.8 kHz, and vanished for 5 and 6 kHz. The results are discussed using a cubic distortion model based on the Boltzmann function for mechano-electrical transduction of the hair cells. The saturation behavior of the increase of the DPOAE level at different phases is compared with the growth rates of the DPOAE level in normal hearing and in sensory hearing loss.

Localization of the palmitoylation site in the transmembrane protein p12E of Friend murine leukaemia virus

Friend murine leukaemia virus complex was propagated on murine cells in the presence of [9,10-3H]palmitic acid. Virus particles were harvested from the culture supernatant and lysed with detergents. The viral transmembrane protein, p12E, was isolated from the lysates by size-exclusion chromatography and purified by narrowbore reverse-phase HPLC. Analysis of the purified product by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) revealed that the protein is palmitoylated carrying one fatty acid residue. The radiolabelled fatty acid was released by hydroxylamine treatment at pH 7, indicating that acylation occurred via a thioester linkage. For allocation of the acylation site, p12E was digested with trypsin. The resulting peptides were either directly subjected to MALDI-TOF-MS or fractionated by microbore reverse-phase HPLC prior to mass spectrometry. The results revealed that p12E of Friend murine leukaemia virus is acylated at a cysteine residue situated at the C-terminal side of the putative transmembrane anchor of the polypeptide. Fatty acid analysis of the purified acylpeptide demonstrated that p12E carries almost exclusively palmitic acid.

Kinetic studies of phenol degradation by Rhodococcus sp. P1. II. Continuous cultivation

The degradation of phenol by Rhodococcus sp. P1 was studied in continuous culture systems. The organism could be adapted by slowly increasing concentration, step by step, up to 30.0 g.l-1 phenol in the influent. The degradation rate reached values of about 0.3 g.g dry mass-1.h-1. Large step increases in phenol concentration and addition of further substrates (e.g., catechol) were tolerated up to a certain concentration. With increasing dilution rate and increasing inlet phenol concentration the stability of the system decreased. Nomenclature: D--Dilution rate, h-1, Dc--Critical dilution rate, h-1, Dx--Yield, g dry mass.l-1.h-1, Ks--Monod saturation constant, g.l-1, S--Growth-limiting substrate concentration in culture broth, g.l-1, SR--Growth-limiting substrate concentration in feed, g.l-1, mean--Biomass concentration in culture broth, g.l-1, YS--Yield constant, g cell dry mass.g substrate-1, mu--Specific growth rate, h-1, mu max--Maximum growth rate, h-1.

Kinetic studies of phenol degradation by Rhodococcus sp. P1. I. Batch cultivation

Rhodococcus sp. P1 utilizes phenol as the sole carbon and energy source via the beta-ketoadipate pathway. In batch cultivation, concentrations up to 2.8 g.l-1 phenol were degraded. The highest values for the specific growth rate of 0.32 h-1 were obtained at concentrations near 0.25 g.l-1. At higher concentrations, substrate inhibition was observed, characterized by increases in lag phase and decreasing growth rates. A mathematical expression was proposed to fit the kinetic pattern of phenol inhibition on the specific growth rate mu: [formula: see text] Nomenclature: K- Exponent of the inhibition function, Ks- Monod saturation constant, g.l-1, KI- Inhibition constant, g.l-1, S- Substrate concentration in culture broth, g.l-1, So- Initial substrate concentration, g.l-1, Y- Yield constant, g cell dry mass.g substrate-1, mu- Specific growth rate, h-1, mu max- Maximum growth rate, h-1.

[Porphyria cutanea tarda and lupus erythematosus]

We observed three patients with lupus erythematosus and porphyria cutanea tarda manifesting itself simultaneously or subsequently. The possible coincidence of the two diseases might be the consequence of immunological communities indicated on the assumption of a genetically coined hepatic uroporphyrinogen decarboxylase defect. The treatment of the lupus erythematosus can be performed according to corresponding observations of the course according to general acknowledged principles including the administration of cytostatic drugs, if the chloroquine phosphate therapy which is clearing up the porphyria cutanea tarda is beginning with low dosages. The fluorescence of the fresh kidney bioptate under long-wave UV-light in porphyria cutanea tarda is referred to for the first time.

[Wegener's granulomatosis with pronounced kidney involvement]

It is reported on the course of histologically ascertained Wegeners' granulomatosis in 4 patients. After initial affection of the upper respiratory tract in form of necrotizing and granulomatous inflammations in all cases a generalisation of the disease with above all early and severe participation of the kidneys developed. Maximum acceleration of sedimentation, C-reactive protein, anaemia, leucocytosis, eosinophilia, thrombocytosis, enlargement of the number of alpha 2-globulins, increase of creatinine, proteinuria, erythrocyturia and leucocyturia are the most frequent pathological laboratory findings, whereas LE-cells, ANF, rheumatoid factor and decrease of the complement never could be proved. By reason of a pathogenic immunoreaction a combined glucocorticoid therapy and immunosuppressive therapy with prednisolone and cyclophosphamide may favourably influence the course of the disease which is otherwise prognostically infaust.

[Bronchial adenoma with uncommon growth (author's transl)]

Report on a bronchial adenoma in the right lobus inferior pulmonalis (autopsy: histological bronchial adenoma from carcinoid type) of uncommon size and with growth till now not described. The tumor was diagnosed clinically and histologically 4 years before death of the patient, but was not operated. The tumor has continuously infiltrated the left atrium cordis via a vena pulmonalis. This case is stressing the decisive importance of the early diagnosis of bronchial adenoma.