The correlation between neuropathology levels and cognitive performance in centenarians

INTRODUCTION

Neuropathological substrates associated with neurodegeneration occur in brains of the oldest old. How does this affect cognitive performance?

METHODS

The 100-plus Study is an ongoing longitudinal cohort study of centenarians who self-report to be cognitively healthy; post mortem brain donation is optional. In 85 centenarian brains, we explored the correlations between the levels of 11 neuropathological substrates with ante mortem performance on 12 neuropsychological tests.

RESULTS

Levels of neuropathological substrates varied: we observed levels up to Thal-amyloid beta phase 5, Braak-neurofibrillary tangle (NFT) stage V, Consortium to Establish a Registry for Alzheimer's Disease (CERAD)-neuritic plaque score 3, Thal-cerebral amyloid angiopathy stage 3, Tar-DNA binding protein 43 (TDP-43) stage 3, hippocampal sclerosis stage 1, Braak-Lewy bodies stage 6, atherosclerosis stage 3, cerebral infarcts stage 1, and cerebral atrophy stage 2. Granulovacuolar degeneration occurred in all centenarians. Some high performers had the highest neuropathology scores.

DISCUSSION

Only Braak-NFT stage and limbic-predominant age-related TDP-43 encephalopathy (LATE) pathology associated significantly with performance across multiple cognitive domains. Of all cognitive tests, the clock-drawing test was particularly sensitive to levels of multiple neuropathologies.

Carriers of the p.P522R variant in PLCγ2 have a slightly more responsive immune system

BACKGROUND

The rs72824905 single-nucleotide polymorphism in the PLCG2 gene, encoding the p.P522R residue change in Phospholipase C gamma 2 (PLCγ2), associates with protection against several dementia subtypes and with increased likelihood of longevity. Cell lines and animal models indicated that p.P522R is a functional hypermorph. We aimed to confirm this in human circulating peripheral immune cells.

METHODS

We compared effects of p.P522R on immune system function between carriers and non-carriers (aged 59-103y), using in-depth immunophenotyping, functional B-cell and myeloid cell assays, and in vivo SARS-CoV-2 vaccination.

RESULTS

In line with expectations, p.P522R impacts immune cell function only slightly, but it does so across a wide array of immune cell types. Upon B-cell stimulation, we observed increased PLCγ2 phosphorylation and calcium release, suggesting increased B-cell sensitivity upon antigen recognition. Further, p.P522R-carriers had higher numbers of CD20++CD21-CD24+ naive B cells and IgG1+ memory B cells. In myeloid cells, normalized ROS production was higher upon PLCγ2-dependent stimulation. On classical monocytes, CD33 levels were elevated. Furthermore, carriers expressed lower levels of allergy-related FcεRI on several immune cell subsets. Nevertheless, carriers and non-carriers had similar serological responses to SARS-CoV-2 vaccination.

CONCLUSION

The immune system from p.P522R-carriers is slightly more responsive to stimulation than in non-carriers.

Protocol of a study to evaluate a lifestyle intervention during pregnancy

Background

The risk of developing obesity and chronic diseases (e.g. diabetes mellitus) in children is influenced by the mother's lifestyle during pregnancy (prenatal programming). This study evaluates a computer-assisted preventive lifestyle counseling carried out during prenatal visits and infant check-ups. GeMuKi (acronym for 'strengthening health promotion: enhanced check-up visits for mother and child') is a complex intervention consisting of multiple components implemented by different cooperating healthcare providers.

Methods

GeMuKi supplements regular prenatal visits and infant check-ups with an additional counseling regarding physical activity, nutrition and alcohol and tobacco use. Providers, who carry out the counseling, receive communication training using motivational interviewing techniques. Pregnant women in 4 intervention regions in Germany receive GeMuKi from gynecologists, midwives and pediatricians, while participants in the 4 control regions receive standard care. As part of a hybrid effectiveness-implementation trial with 1860 participants, questionnaires are filled in at 4 time points. Weight development and health data of the mother and child are recorded. Health services use will be analyzed using statutory health insurance claims data. Interviews will be conducted to evaluate the implementation process.

Results

Targeted preventive measures at the beginning of pregnancy intend to reduce the risk of inadequate gestational weight gain (primary outcome). Secondary endpoints are amongst others maternal lifestyle, infant weight development and body composition.

Conclusions

GeMuKi is set up as a long-term, low-threshold, multimodal intervention in living environments and existing structures. Findings will add to the evidence on lifestyle interventions during pregnancy to reduce the risk for overweight and obesity. Results will contribute to the prevention of early programming of chronic disease and will inform decisions about scale up and public funding.

Key messages

Lifestyle interventions provided from the beginning of pregnancy intent to be beneficial for the health of both mother and child to prevent obesity and chronic diseases. Low-threshold interventions embedded in regular prenatal visits are accessible for the complete pregnant population, including vulnerable groups.

Optimal surface estimation and thresholding of confocal microscope images of biofilms using Beer's Law

Beer's Law explains how light attenuates into thick specimens, including thick biofilms. We use a Bayesian optimality criterion, the maximum of the posterior probability distribution, and computationally efficiently fit Beer's Law to the 3D intensity data collected from thick living biofilms by a confocal scanning laser microscope. Using this approach the top surface of the biofilm and an optimal image threshold can be estimated. Biofilm characteristics, such as bio-volumes, can be calculated from this surface. Results from the Bayesian approach are compared to other approaches including the method of maximum likelihood or simply counting bright pixels. Uncertainty quantification (i.e., error bars) can be provided for the parameters of interest. This approach is applied to confocal images of stained biofilms of a common lab strain of Pseudomonas aeruginosa, stained biofilms of Janthinobacterium isolated from the Antarctic, and biofilms of Staphylococcusaureus that have been genetically modified to fluoresce green.

Standard Test Method ASTM D 7998-19 for the Cohesive Strength Development of Wood Adhesives

The properties of cured wood adhesives are difficult to study because of the loss of water and other components to the wood, the influence of wood on the adhesive cure, and the effect of adhesive penetration on the wood interphase; thus, normal testing of a neat adhesive film is generally not useful. Most tests of wood adhesive bond strength are slow, laborious, can be strongly influenced by the wood and do not provide information on the kinetics of cure. Test method ASTM D 7998-19, however, can be used for fast evaluation of the strength of wood bonds. The use of a smooth, uniform, and strong wood surface, like maple face-veneer, and sufficient bonding pressure reduces the adhesion and wood strength effects on bond strength. This method has three main applications. The first is to provide consistent data on bond strength development. The second is to measure the dry and wet strengths of bonded lap shear samples. The third is to better understand the adhesive heat resistance by quickly evaluating thermal sensitivity and distinguishing between thermal softening and thermal degradation.

The effect of skin-to-skin care on cerebral oxygenation during nasogastric feeding of preterm infants

AIM

To describe cerebral oxygenation during gavage feeding of preterm infants during incubator and skin-to-skin care.

METHODS

Further analysis of data from two crossover studies comparing cerebral oxygenation, heart rate and oxygen saturation during skin-to-skin care with incubator care. Data were analysed in three epochs; 10 minutes prefeed, during-feed and 10 minutes postfeed. Measurements from infants fed during incubator care were compared with those obtained during skin-to-skin care.

RESULTS

In 39 infants [median (IQR) 27.8 (26.1-30.0) weeks' gestation], there was no difference in cerebral oxygenation between pre-, during- and postfeed. Heart rate increased by three beats per minute postfeed compared with during-feed. Twenty infants received two gavage feeds, one feed in the incubator and another during skin-to-skin care. There was no difference in cerebral oxygenation and heart rate; peripheral oxygen saturation decreased by 3% during feeding whilst skin-to-skin care compared with feeding in the incubator.

CONCLUSION

Cerebral oxygenation remained stable before, during and after gavage feeding in an incubator and during skin-to-skin care. The small decrease in oxygen saturation whilst receiving gavage feeding during skin-to-skin care is unlikely to be clinically important, providing reassurance that preterm infants maintain physiological stability during skin-to-skin care.

Paired methods to measure biofilm killing and removal: a case study with Penicillin G treatment of Staphylococcus aureus biofilm

Biofilms are microbial aggregates that show high tolerance to antibiotic treatments in vitro and in vivo. Killing and removal are both important in biofilm control, therefore methods that measure these two mechanisms were evaluated in a parallel experimental design. Kill was measured using the single tube method (ASTM method E2871) and removal was determined by video microscopy and image analysis using a new treatment flow cell. The advantage of the parallel test design is that both methods used biofilm covered coupons harvested from a CDC biofilm reactor, a well-established and standardized biofilm growth method. The control Staphylococcus aureus biofilms treated with growth medium increased by 0·6 logs during a 3-h contact time. Efficacy testing showed biofilms exposed to 400 μmol l^-1 penicillin G decreased by only 0·3 logs. Interestingly, time-lapse confocal scanning laser microscopy revealed that penicillin G treatment dispersed the biofilm despite being an ineffective killing agent. In addition, no biofilm removal was detected when assays were performed in 96-well plates. These results illustrate that biofilm behaviour and impact of treatments can vary substantially when assayed by different methods. Measuring both killing and removal with well-characterized methods will be crucial for the discovery of new anti-biofilm strategies.

SIGNIFICANCE AND IMPACT OF THE STUDY

Biofilms are tolerant to antimicrobial treatments and can lead to persistent infections. Finding new anti-biofilm strategies and understanding their mode-of-action is therefore of high importance. Historically, antimicrobial testing has focused on measuring the decrease in viability. While kill data are undeniably important, measuring biofilm disruption provides equally useful information. Starting with biofilm grown in the same reactor, we paired assessment of biofilm removal using a new treatment-flow-cell and real-time microscopy with kill data collected using the single tube method (ASTM E2871). Pairing these two methods revealed efficient biofilm removal properties of Penicillin G which were not detected during efficacy testing.

The Adjustment Disorder--New Module 20 as a Screening Instrument: Cluster Analysis and Cut-off Values

BACKGROUND

Adjustment disorder (AjD) is a transient mental health condition emerging after stressful life events. Its diagnostic criteria have recently been under revision which led to the development of the Adjustment Disorder--New Module 20 (ADNM-20) as a self-report assessment.

OBJECTIVE

To identify a threshold value for people at high risk for AjD.

METHODS

As part of a randomized controlled trial evaluating a self-help manual for burglary victims, the baseline data of all participants (n=80) were analyzed. Besides the ADNM-20, participants answered self-report questionnaires regarding the external variables post-traumatic stress disorder symptomatology, depression, anxiety, and stress levels. We used cluster analysis and ROC analysis to identify the most appropriate cut-off value.

RESULTS

The cluster analysis identified three different subgroups. They differed in their level of AjD symptomatology from low to high symptom severity. The same pattern of impairment was found for the external variables. The ROC analysis testing the ADNM-20 sum scoreagainst the theory-based diagnostic algorithm, revealed an optimal cut-off score at 47.5 to distinguish between people at high risk for AjD and people at low risk.

CONCLUSION

The ADNM-20 distinguishes between people with low, moderate, and high symptomatology. The recommendation for a cut-off score at 47.5 facilitates the use of the ADNM-20 in research and practice.

Synchrotron-based X-ray fluorescence microscopy in conjunction with nanoindentation to study molecular-scale interactions of phenol-formaldehyde in wood cell walls

Understanding and controlling molecular-scale interactions between adhesives and wood polymers are critical to accelerate the development of improved adhesives for advanced wood-based materials. The submicrometer resolution of synchrotron-based X-ray fluorescence microscopy (XFM) was found capable of mapping and quantifying infiltration of Br-labeled phenol-formaldehyde (BrPF) into wood cell walls. Cell wall infiltration of five BrPF adhesives with different average molecular weights (MWs) was mapped. Nanoindentation on the same cell walls was performed to assess the effects of BrPF infiltration on cell wall hygromechanical properties. For the same amount of weight uptake, lower MW BrPF adhesives were found to be more effective at decreasing moisture-induced mechanical softening. This greater effectiveness of lower MW phenolic adhesives likely resulted from their ability to more intimately associate with water sorption sites in the wood polymers. Evidence also suggests that a BrPF interpenetrating polymer network (IPN) formed within the wood polymers, which might also decrease moisture sorption by mechanically restraining wood polymers during swelling.

Combined 17beta-oestradiol and progesterone treatment prevents neuronal cell injury in cortical but not midbrain neurones or neuroblastoma cells

Oestrogens are powerful endogenous and exogenous neuroprotective hormones in animal models of brain injury, including focal cerebral ischaemia. This protective effect has been demonstrated under a variety of different treatments and injury paradigms, such as in vivo and in vitro stroke conditions. Neuroprotection in the central nervous system by progesterone is less defined. In the present study, cultured cortical and midbrain mouse neurones and human neuroblastoma cells (SH-SY5Y) were exposed to combined glucose-serum deprivation (CGSD), which is regarded as a reliable model mimicking the effects of ischaemia in vitro. Cell viability was assayed using lactate dehydrogenase release and metabolic activity. Conditions for CGSD treatment were chosen to yield half-maximal cell death rates. The validity of CGSD in vitro was compared with permanent middle cerebral artery occlusion (MCAO) in vivo. CGSD for 4 h induced half-maximal neuronal cell death. MCAO in vivo for the same period resulted in significant neuronal loss, also suggesting the validity of CGSD as a suitable stroke-like in vitro model. Combined steroid treatment (17beta-oestradiol and progesterone) but not the application of single steroids abolished CGSD-induced cell death of cortical neurones in vitro. By contrast, no cell protection was found in midbrain neurones or neuroblastoma cells. The co-application of oestrogen (ICI 182,780) or progesterone (RU-486) receptor antagonists did not obviously counteract the protective steroid effects. This suggests the operation of nonclassical steroid mechanisms and their implication in mediation of hormonal effects. The surplus of combined protective hormonal effects might be a result of the observed influence of progesterone application on neuronal oestradiol synthesis. The data obtained in the present study clearly highlight the potential of a combined steroid treatment under toxic degenerative brain pathologies.

The effects of dietary supplementation with isoflavones from red clover on cognitive function in postmenopausal women

OBJECTIVE

To examine the effects of dietary isoflavone supplementation with an extract from red clover on cognitive function in postmenopausal women.

DESIGN

Thirty postmenopausal women aged greater than 60 years received either two tablets of an extract of aglycone isoflavones from red clover (each containing formononetin 25 mg, biochanin 2.5 mg and less than 1 mg of daidzein and genistein) for 6 months in a randomized, controlled clinical trial. Cognitive function tests were performed at baseline and at the end of isoflavone or placebo therapy.

RESULTS

Isoflavone supplementation was associated with an apparent improvement in block design (a test of visual-spatial intelligence) compared to placebo (isoflavone +12%, placebo -3%; p = 0.03), no improvement in verbal memory compared to an improvement on placebo (isoflavone +1%, placebo +29%; p = 0.023) and a deterioration in digit recall compared to placebo (isoflavone -6%, placebo +12%; p = 0.029). However, these findings were not statistically significant when corrections were made for potential chance findings due to multiple comparisons.

CONCLUSION

Isoflavone supplementation does not appear to have major short-term effects on cognitive function in postmenopausal women. However, further clinical trials are required to determine whether small effects or long-term effects on cognitive function occur during isoflavone supplementation.

Nursing attire: indicators of professionalism?

The purpose of this qualitative research was to explore the effect that current nursing attire has on the image of the nursing profession. A number of nurses and a nonnurse were interviewed to determine how attire affected their perception of today's nurses. The two research questions were as follows: (1) is the changing dress of nurses projecting a negative image to the public? and (2) What components of a nurse's apparel indicate professionalism? Content analysis was performed on transcriptions from the tape-recorded responses of a purposeful sample of health care workers: 12 registered nurses, 1 bachelor of nursing student, and 1 layperson. The responses for the first research question were not directly addressed by the participants. However, one overall theme emerged, which was labeled "I can't tell you what it is, but I know it when I see it." The main theme that emerged for the second research question was labeled "total package," with role identification and competency being related themes. As a result of this research, nursing administrators and other health care professionals could gain an understanding of the importance of nursing attire as an indicator of nursing professionalism. Future research needs to examine the same research questions with health care consumers in a variety of acute and community-based health care settings.

Selecting and implementing support groups for bereaved adults

PURPOSE

This paper offers a rationale for initiating bereavement support groups in sites providing cancer care and delineates models to implement them. Skills needed to lead a bereavement support group are identified, with emphasis on adding to staff members' competency that has already been developed by facilitating groups for oncology patients and their families.

OVERVIEW

Bereavement support groups are essential elements in the provision of comprehensive oncology care, though they are seldom offered by staff in the traditional hospital setting. It is important that the bereaved feel that there is a place in which they have the time and understanding required to work through the normal grieving process. Special requirements for facilitators include self-awareness of the impact of loss in their own lives and ability to tolerate both the emotions expressed in the grieving process and the often extended time period required for members' personal healing. Several bereavement support models, including the time-limited, ongoing, monthly, and self-help groups, are documented.

CLINICAL IMPLICATIONS

Bereavement support is an essential element in the provision of comprehensive oncology care. Predictive models to identify individuals who are at higher risk for psychological distress could be used in oncology clinics to facilitate early referral or greater psychological support for family members. Staff members wishing to introduce this service can build on skills already developed leading traditional oncology support groups, and can utilize cofacilitation with a mental health professional to ease the anxiety of assuming a new role and obtain mentoring. Recruitment for a group might be achieved by inviting family members of patients who have died within a specific time frame or by issuing press releases to local papers and church bulletins. Offering bereavement support in the oncology setting is especially helpful to family members who might otherwise be unaware of such a service and who now have the opportunity to attend.

Take good care of yourself

Caring for the terminally ill can have a cumulative effect on the caregiver, who may begin to view life as a succession of endless sufferings, as well as feel guilty for his or her own good health. Taking the time to care for oneself is not only necessary to maintain good mental and physical health, it is an essential part of the care extended to others.

Spatial and temporal expression of the period gene in Drosophila melanogaster

The temporal and spatial expression of the period gene of Drosophila melanogaster has been analyzed by examining the expression of a per beta-galactosidase fusion gene in transformants and by in situ hybridization experiments with wild-type flies. Several strains of Drosophila melanogaster, transformed with the fusion gene, have been generated. The gene is active in mid-late embryos in the midline of the nervous system. Thereafter, beta-galactosidase activity is undetectable until the pupal stage when the prothoracic gland-corpora allata and the optic lobes are beta-galactosidase positive. In adults a surprisingly large number of tissues stain positively, including antennae, proboscis, eyes, optic lobes, cells of the central brain, cells of the thoracic ganglia, gut, Malpighian tubules, and ovarian follicle cells. The temporal pattern of expression agrees well with previous estimates made from developmental Northern blots with RNA extracted from wild-type animals. We suggest that many of the tissues that express the per gene contain their own intrinsic oscillator activity.

Oral infection of Aedes aegypti with yellow fever virus: geographic variation and genetic considerations

Twenty-eight populations representing a worldwide distribution of Aedes aegypti were tested for their ability to become orally infected with yellow fever virus (YFV). Populations had been analyzed for genetic variations at 11 isozyme loci and assigned to one of 8 genetic geographic groups of Ae. aegypti. Infection rates suggest that populations showing isozyme genetic relatedness also demonstrate similarity to oral infection rates with YFV. The findings support the hypothesis that genetic variation exists for oral susceptibility to YFV in Ae. aegypti.

Selection for susceptibility and refractoriness of Aedes aegypti to oral infection with yellow fever virus

Artificial selection on strains of Aedes aegypti showing susceptibility and refractoriness to oral infection with yellow fever virus (YFV) suggests that there is a significant genetic component to this trait. Using a population with an average susceptibility of 15%, inbreeding of isofemale lines followed by individual selection produced susceptible (29% infected) and refractory (11% infected) lines. The difference between lines was largely apparent before individual selection, which failed to increase/decrease susceptibility significantly. The findings suggest that very few loci with a major bearing on the trait segregated genetic variation in the original population sample, and that non-genetic factors also play a major role in determining whether or not Ae. aegypti females become infected with YFV.

The effect of colonization upon aedes aegypti susceptibility to oral infection with yellow fever virus

Two colonies of Aedes aegypti were established from two independent collections from Vero Beach, Florida. Eleven sequential generations of the first colony were tested for variation in oral susceptibility to infection with yellow fever virus (YFV). Each generation was also assayed for genetic variability at seven enzyme loci using electrophoretic techniques. Significant differences in infection rates were detected between some generations. These differences were significantly correlated with genetic variation at the malate dehydrogenase locus. Seven generations from the second colony were examined simultaneously for variation in susceptibility to YFV. Significant differences were also detected between some of these generations. The results suggest that colonization may have an effect on the genetic and phenotypic variation in a mosquito strain, and that genetically based variation for susceptibility to infection with YFV occurs in populations of Ae. aegypti.