Genetic screening of South African families with Parkinson's disease

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Cost-Effectiveness of Prevention for People at Risk for Dementia: A Scoping Review and Qualitative Synthesis

Dementia is from an economic perspective a main challenge for economies worldwide because of increasing costs. Since there is no cure in sight, prevention seems the most promising approach for reducing health care cost due to Dementia. On the contrary, approximately 40% of dementias is attributable to modifiable risk factors and first studies showed that multidomain interventions may be effective for preventing dementia. Considering the increasing economic burden, for many health administrations worldwide, cost-effectiveness plays a mayor role. This scoping review wants to bring evidence to the question if prevention for people at risk may be cost-effective. Therefore, the four databases Medline (via Pubmed), CINHAL (via EBSCO), Business Source Complete (via EBSCO), and the Health Economic Evaluation database (HEED) were used to conduct a scoping review using PICO and a systematic search string. 3,629 studies were identified and seven met all inclusion criteria. The included studies showed clear cost-effectiveness for most multidomain interventions. The gained QALYs at mean were 0.08 (SD=0.08) and the intervention average costs 472.20 EUR per Person (SD=74.06 EUR). The Incremental Cost-Effectiveness Ratios varied between -80,427.97 and 104,189.82 EUR per QALY. The three core results are (i) prevention programs focusing on people at risk may be cost-effective and cost-efficient, (ii) multimodal prevention reveal cost saving potential, when the people at risk are defined well, (iii prevention in middle-aged cohorts may be also cost-effective if life-style related risk factors are addressed.

Are you better than me? Social comparisons in carrion crows (Corvus corone)

Comparing oneself to others is a key process in humans that allows individuals to gauge their performances and abilities and thus develop and calibrate their self-image. Little is known about its evolutionary foundations. A key feature of social comparison is the sensitivity to other individuals' performance. Recent studies on primates produced equivocal results, leading us to distinguish between a 'strong' variant of the social comparison hypothesis formulated for humans and a 'weak' variant found in non-human primates that would comprise some elements of human social comparison. Here, we focus on corvids that are distantly related to primates and renowned for their socio-cognitive skills. We were interested in whether crows' task performances were influenced (i) by the presence of a conspecific co-actor performing the same discrimination task and (ii) by the simulated acoustic cues of a putative co-actor performing better or worse than themselves. Crows reached a learning criterion quicker when tested simultaneously as compared to when tested alone, indicating a facilitating effect of social context. The performance of a putative co-actor influenced their performance: crows were better at discriminating familiar images when their co-actor was better than they were. Standard extremity (how pronounced the difference was between the performance of the subject and that of the co-actor), and category membership (affiliation status and sex), of the putative co-actors had no effect on their performance. Our findings are in line with the 'weak' variant of social comparison and indicate that elements of human social comparison can be found outside of primates.

The relationship between the recognition of specific basic emotions and negative symptom domains in patients with schizophrenia spectrum disorders

Introduction

Current research suggests emotion recognition to be significantly impaired in individuals with schizophrenia spectrum disorders (SSD), whereby negative symptoms are theorised to play a crucial role. Emotion recognition deficits are assumed to be predictors of transition from clinical high risk to schizophrenia. So far, little attention has been given hereby to the subdomains of negative symptoms and recognizing the individual basic emotions.

Objectives

Our study aimed to explore the relationship between the recognition of the basic emotions and each negative symptom domain.

Methods

66 patients with a SSD diagnosis were recruited at the Charité – Universitätsmedizin Berlin. Correlational and regression analyses to control for the covariates (age, education, sex) were conducted between the recognition of the six basic emotions (anger, disgust, fear, happiness, sadness, surprise) using the Emotion Recognition Task of the Cambridge Neuropsychological Test Automated Battery (CANTAB) and the seven different subdomains of negative symptoms of the Positive and Negative Syndrome Scale (PANSS).

Results

revealed significantly negative correlations of blunted affect with the recognition of happiness, fear, and disgust. Difficulties in abstract thinking, also correlated positively with the recognition of fear. Additionally, we found a significant positive correlation between stereotyped thinking and difficulties in abstract thinking with the response latency in emotion recognition.

Conclusions

Individuals with SSD and domains of negative symptoms showed specific impairments in recognizing the representation of basic emotions. A longitudinal design to make causality statements would be useful for future research. Moreover, emotion recognition should be considered for early detection and individualized treatment.

Disclosure

No significant relationships.

Increasing sample diversity in psychiatric genetics - Introducing a new cohort of patients with schizophrenia and controls from Vietnam - Results from a pilot study

OBJECTIVES

Genome-Wide Association Studies (GWAS) of Schizophrenia (SCZ) have provided new biological insights; however, most cohorts are of European ancestry. As a result, derived polygenic risk scores (PRS) show decreased predictive power when applied to populations of different ancestries. We aimed to assess the feasibility of a large-scale data collection in Hanoi, Vietnam, contribute to international efforts to diversify ancestry in SCZ genetic research and examine the transferability of SCZ-PRS to individuals of Vietnamese Kinh ancestry.

METHODS

In a pilot study, 368 individuals (including 190 SCZ cases) were recruited at the Hanoi Medical University's associated psychiatric hospitals and outpatient facilities. Data collection included sociodemographic data, baseline clinical data, clinical interviews assessing symptom severity and genome-wide SNP genotyping. SCZ-PRS were generated using different training data sets: (i) European, (ii) East-Asian and (iii) trans-ancestry GWAS summary statistics from the latest SCZ GWAS meta-analysis.

RESULTS

SCZ-PRS significantly predicted case status in Vietnamese individuals using mixed-ancestry (R² liability = 4.9%, p = 6.83 × 10^-8), East-Asian (R² liability = 4.5%, p = 2.73 × 10^-7) and European (R² liability = 3.8%, p = 1.79 × 10^-6) discovery samples.

DISCUSSION

Our results corroborate previous findings of reduced PRS predictive power across populations, highlighting the importance of ancestral diversity in GWA studies.

Histopathologic spectrum of glomangioma: A clinico-pathologic review

Introduction/Objective

Glomus tumors are mesenchymal neoplasms with glomus body type modified smooth muscle cell differentiation. Most glomus tumors have a benign clinical course. However, rarely, they display malignant histologic features.

Methods/Case Report

We undertook a retrospective study using a natural language search in CoPath to find surgical pathology cases from 1993-2020 containing “glomus” in the pathology diagnosis. All relevant cases were included, and clinicopathologic data were reviewed in detail.

Results (if a Case Study enter NA)

A total of 66 tumors were identified, of which 42 were in female (63.6%) and 24 in male (36.4%) patients. The age at surgery ranged from 22 to 79 years with a median of 47.5. Females were significantly younger than males at presentation (p=0.025) by 8.8±3.8 years. Forty cases (60.6%) were located on the digits, 24 in nonvisceral soft tissue of extremities, trunk, and lip (36.4%), and one each in stomach and breast parenchyma. Sixty-three (95.5%) were benign (of which one recurred locally), 2 (3%) were malignant, and 1 (1.5%) was atypical. Four (6%) were multicentric. One case showed mixed histology (oncocytic and classic features) and one was classified as glomangiomatosis. The malignant cases each presented with a single tumor in lower extremity soft tissue in female patients (aged 33 and 49 years). The tumors measured 0.5 and 1.8 cm respectively and showed marked cytologic atypia in both and increased mitotic activity in the first. They were both completely excised.

Conclusion

The majority of glomus tumors are benign, however 3% are malignant. The most common location is the digits, followed by soft tissue. This tumor is more commonly seen in female patients. Unusual histologic variants such as glomangiomatosis and oncocytic component at times may create some difficulty to reach the diagnosis, especially on small biopsies. Unusual locations such as stomach can lead to a wrong diagnosis such as carcinoid, especially in a small biopsy material.

Introducing a psychiatric genetic cohort of schizophrenia patients and controls from Vietnam

Introduction

Genome-wide association studies (GWAS) have successfully revealed genetic risk variants for schizophrenia (SCZ). However, the vast majority of GWAS largely comprise European samples. As a result, the derived polygenic risk scores (PRS) show decreased predictive power when applied to non-European populations.

Objectives

A long-term scientific cooperation between the Charité Universitätsmedizin Berlin and the Hanoi Medical University aims to address this limitation by recruiting a large genetic cohort of comprehensively phenotyped schizophrenia patients and controls in Vietnam.

Methods

A pilot study was conducted at the Department of Psychiatry of the Medical University Hanoi in 2017. Data collection encompassed i) genome-wide SNP genotyping of 200 schizophrenia patients and 200 control subjects ii) structured interviews to assess symptom severity (PANSS), iii) clinical parameters (e.g. duration of illness, medication) and demography.

Results

SCZ-PRS of the pilot sample (N=400) were generated using different training data sets: i) European, ii) East-Asian and iii) mixed GWAS summary statistics from the Psychiatric Genomics Consortium’s latest discovery sample. Most variance explained was observed using a mixed discovery sample (R²liability=0.053, p=3.11*10^-8, Pd <0.5), followed by PRS based on the East-Asian summary statistics (R²liability=0.0503, p=6.78*10^-8, Pd <1) and the European sample (R²liability=0.0363, p = 4.26*10^-6, Pd <0.01).

Conclusions

With this pilot project we established an efficient recruitment, genotyping and data analysis pipeline. Our results corroborate previous findings indicating that transferability of PRS across populations depends on the ancestral composition of the initial discovery dataset. We therefore aim to expand data collection efforts in the future in order to improve risk prediction across diverse populations.

Disclosure

No significant relationships.

Reform design, institutional and workforce factors affecting the pace of change

Background

When implementing health care reforms the pace of change is often lacking behind the expectations of policy makers. This research is exploring in-depth the experiences of a primary care initiative from the perspective of general practitioners. The physicians' perspectives on design features, supporting environment and acceptance of the pilot are being explored. Enabling and constraining factors that may influence the pace of change of health care reforms are identified. Implications can be drawn for the strategic planning and smooth implementation of the change process.

Methods

14 problem-focused interviews with general practitioners working in pilot projects and 2 focus group discussions with 4-6 general practitioners working in single practices have been conducted. In addition, document analysis of secondary qualitative data and relevant policy documents has been conducted.

Results

Analysis revealed 9 codes: (1) Status of the general practitioner; (2) Institutional and legal framework; (3) Between cooperation and competition; (4) Hesitation from the young generation; (5) Reluctance from sole practitioners; (6) Personal drivers for starting a pilot (7) Challenges during set-up phase; (8) Challenges during growth phase; (9) Working conditions in primary care pilot projects. Enabling factors were a strong desire to be pioneering primary care provision and improved working conditions. The main constraining factors were low status of the general practitioner, uncertainty about future directions, lack of information and advice, high perceived financial risk, fear of losing autonomy and uncertainty about functioning teamwork.

Conclusions

For a smooth implementation of the primary care reform, system changes should improve education and training, compensation schemes and competence profiles of the professional groups involved. Further, initiatives should provide information and advice for practitioners striving for participating in a pilot project.

Key messages

The success of health care reforms also depends on institutional and workforce factors that may affect the pace of change. Health care reforms need strategic planning for a smooth implementation.

P1836 Common carotid artery intima-media thickness correlates with the epicardial fat thickness in patients with ischemic stroke

Purpose

The aim of this study was to determine the relationship between common carotid artery intima–media thickness (CCA-IMT), the resistance index (RI) in the vertebral and carotid arteries and epicardial fat thickness (EFT) in patients with ischemic stroke.

Methods

98 patients with ischemic stroke (31 females and 67 males, mean age was 68.2 ± 12.1 years) were studied. All patients had arterial hypertension (AH). Most of them (96.9%) had grade 3 hypertension according to ESH/ESC Guidelines for the management of arterial hypertension, 2018. Forty-two (43.1%) patients had coronary artery disease and 35 (35.4%) - atrial fibrillation (AF). The exclusion criteria was the presence of chronic obstructive pulmonary disease or other diseases associated with pulmonary hypertension. Patients were categorized according to National Institutes of Health Stroke Scale (NIHSS) severity in mild NIHSS (≤8) - 54 (55.1%) patients, moderate NIHSS (9–15) - 23 (23.5%) patients, and severe stroke NIHSS (≥16) - 21 (21.4%) patients. Median NIHSS score was 11.2 ± 1.7. All patients underwent a transthoracic echocardiography and a carotid ultrasound examination.

Results

The common carotid artery intima–media thickness correlated with EFT (r =0.78, p &lt; 0.001), the body mass index (r = 0.7, p &lt; 0.001) and systolic blood pressure (r = 0.25, p = 0.045). The resistance index in the vertebral and carotid arteries correlated only with EFT (r = 0.7, p &lt; 0.001 and r = 0.78, p &lt; 0.001, respectively) and body mass index (r = 0.58, p &lt; 0.001 and r = 0.68, p &lt; 0.001, respectively).

A multiple regression analysis in which the CCA-IMT was a dependent variable and age, body mass index, systolic blood pressure, blood cholesterol level and epicardial fat thickness were independent variables, showed that CCA-IMT was independently correlated with blood cholesterol level (β=0.714, р&lt;0.001) and EFT (β =0.255, р=0.002) in patients with ischemic stroke.

Conclusions

The common carotid artery intima–media thickness and parameters of the arterial stiffness of the extracranial vessels of the head are associated with the epicardial fat thickness and blood cholesterol level in patients with ischemic stroke. The common carotid artery intima–media thickness does not depend on age, gender, body mass index, systolic and diastolic blood pressure in patients with ischemic stroke.

P1837 The severity of acute ischemic stroke is associated with the right heart remodeling in patients with arterial hypertension

Purpose

The aim of this study was to determine the relationship of echocardiographic signs of the right heart remodeling and the stroke severity in patients with arterial hypertension and ischemic stroke.

Methods

98 patients with acute ischemic stroke (31 females and 67 males, mean age was 68.2 ± 12.1 years) were studied. All patients had arterial hypertension. Most of them (96.9%) had grade 3 hypertension according to ESH/ESC Guidelines for the management of arterial hypertension, 2018. Forty-two (43.1%) patients had coronary artery disease, 35 (35.4%) - atrial fibrillation (AF). The exclusion criteria was the presence of chronic obstructive pulmonary disease or other diseases associated with pulmonary hypertension. Patients were categorized according to National Institutes of Health Stroke Scale (NIHSS) severity in mild NIHSS (≤8) - 54 (55.1%) patients, moderate NIHSS (9–15) - 23 (23.5%) patients, and severe stroke NIHSS (≥16) - 21 (21.4%) patients. Median NIHSS score was 11.2 ± 1.7. All patients underwent a transthoracic echocardiography. A comparative assessment of echocardiographic parameters was performed in patients of lower (NIHSS score ≤ 4.5) and upper (NIHSS score≥14.5) quartile according to the NIHSS score.

Results

Linear regression analysis revealed that stroke severity was significantly correlated with right atrium end-diastolic volume (EDV) (r = 0.48, p &lt; 0.0001), right ventricular EDV (r = 0.62, p &lt; 0.0001), left atrium EDV (r = 0.41, p = 0.002), left ventricular ejection fraction (LVEF) (r = 0.4, p = 0.003) and pulmonary artery systolic pressure (PASP) (r = 0.89, p &lt; 0.0001). A multiple regression analysis showed that stroke severity was independently correlated with PASP (β=0.471, р=0.01), left atrium EDV (β=0.961, р=0.02) and LVEF (β=0.931, р=0.005) in patients with arterial hypertension and ischemic stroke.

In the group of patients with the upper quartile of NIHSS score, the right atrium EDV (64.7 ± 21.1 mm versus 47.6 ± 25.2 mm, р=0.04) and PASP (25.8 ± 9.3 mm versus 20.8 ± 8.0 mm, р=0.045) were higher. The left atrium EDV was higher in patients with LVEF below 50% ( 73.3 ± 36.9 mm vs 49.9 ± 18.5 mm, р=0.02) and in patients with AF (55.3 ± 19.8 vs 36.4 ± 14.6 mm, p &lt; 0.0001). At the same time PASP did not depend on the LVEF (22.1 ± 10.7 mm vs 21.6 ± 8.1 mm, р=0.9) and the presence of AF (21.9 ± 9.0 mm vs 21.7 ± 8.1 mm, р=0.9).

Conclusions

In patients with arterial hypertension the severity of acute ischemic stroke is associated with increases in right atrium end-diastolic volume and in pulmonary artery systolic pressure. An increase in pulmonary artery systolic pressure in patients with arterial hypertension and ischemic stroke does not depend on the left ventricular ejection fraction and atrial fibrillation.

Site-specific gene expression analysis from archived human intestine samples combining laser-capture microdissection and multiplexed color-coded probes

BACKGROUND

Alterations of site-specific gene expression profiles in disease-relevant networks within the different layers of the intestinal wall may contribute to the onset and clinical course of gastrointestinal disorders. To date, no systematic analysis has assessed and compared sub-regional gene expression patterns in all distinct layers of the gut using fresh frozen human samples. Our aim was to establish an optimized protocol for site-specific RNA isolation in order to achieve maximum RNA quality and amount for subsequent gene expression analysis combining laser-capture microdissection (LCM) with a probe-based technology, the NanoString nCounter Analysis system.

METHODS

Four full-thickness colon samples from patients who underwent surgery due to pathological conditions were processed and separated into epithelium, lamina propria, myenteric plexus, submucosa, and tunica muscularis by LCM. Site-specific marker expression by nCounter technology was performed on total RNA from each sub-region, respectively.

KEY RESULTS

Collecting ~10 mm² (~100 000-250 000 cells) of tissue from the epithelial layer, lamina propria, and myenteric plexus provided sufficient amounts of RNA of appropriate quality for subsequent analyses. In contrast, ~40 mm² (~250 000-650 000 cells) of tissue were dissected from the less cell-rich submucosal and tunica muscularis layer. nCounter analysis revealed a site-specific expression pattern of marker genes in the different layers of the colonic wall which were highly correlating (r > .9).

CONCLUSIONS AND INFERENCES

LCM in combination with nCounter expression analysis enables site-specific, sensitive, reliable detection, and quantification of mRNA from histologically heterogeneous tissues.

Lamin B1 regulates somatic mutations and progression of B-cell malignancies

Somatic hypermutation (SHM) is a pivotal process in adaptive immunity that occurs in the germinal centre and allows B cells to change their primary DNA sequence and diversify their antigen receptors. Here, we report that genome binding of Lamin B1, a component of the nuclear envelope involved in epigenetic chromatin regulation, is reduced during B-cell activation and formation of lymphoid germinal centres. Chromatin immunoprecipitation-Seq analysis showed that kappa and heavy variable immunoglobulin domains were released from the Lamin B1 suppressive environment when SHM was induced in B cells. RNA interference-mediated reduction of Lamin B1 resulted in spontaneous SHM as well as kappa-light chain aberrant surface expression. Finally, Lamin B1 expression level correlated with progression-free and overall survival in chronic lymphocytic leukaemia, and was strongly involved in the transformation of follicular lymphoma. In summary, here we report that Lamin B1 is a negative epigenetic regulator of SHM in normal B-cells and a 'mutational gatekeeper', suppressing the aberrant mutations that drive lymphoid malignancy.

Attosecond physics at the nanoscale

Recently two emerging areas of research, attosecond and nanoscale physics, have started to come together. Attosecond physics deals with phenomena occurring when ultrashort laser pulses, with duration on the femto- and sub-femtosecond time scales, interact with atoms, molecules or solids. The laser-induced electron dynamics occurs natively on a timescale down to a few hundred or even tens of attoseconds (1 attosecond  =  1 as  =  10^-18 s), which is comparable with the optical field. For comparison, the revolution of an electron on a 1s orbital of a hydrogen atom is  ∼152 as. On the other hand, the second branch involves the manipulation and engineering of mesoscopic systems, such as solids, metals and dielectrics, with nanometric precision. Although nano-engineering is a vast and well-established research field on its own, the merger with intense laser physics is relatively recent. In this report on progress we present a comprehensive experimental and theoretical overview of physics that takes place when short and intense laser pulses interact with nanosystems, such as metallic and dielectric nanostructures. In particular we elucidate how the spatially inhomogeneous laser induced fields at a nanometer scale modify the laser-driven electron dynamics. Consequently, this has important impact on pivotal processes such as above-threshold ionization and high-order harmonic generation. The deep understanding of the coupled dynamics between these spatially inhomogeneous fields and matter configures a promising way to new avenues of research and applications. Thanks to the maturity that attosecond physics has reached, together with the tremendous advance in material engineering and manipulation techniques, the age of atto-nanophysics has begun, but it is in the initial stage. We present thus some of the open questions, challenges and prospects for experimental confirmation of theoretical predictions, as well as experiments aimed at characterizing the induced fields and the unique electron dynamics initiated by them with high temporal and spatial resolution.

Transfer characteristics of subretinal visual implants: corneally recorded implant responses

PURPOSE

The subretinal Alpha IMS visual implant is a CE-approved medical device for restoration of visual functions in blind patients with end-stage outer retina degeneration. We present a method to test the function of the implant objectively in vivo using standard electroretinographic equipment and to assess the devices' parameter range for an optimal perception.

METHODS

Subretinal implant Alpha IMS (Retina Implant AG, Reutlingen, Germany) consists of 1500 photodiode-amplifier-electrode units and is implanted surgically into the subretinal space in blind retinitis pigmentosa patients. The voltages that regulate the amplifiers' sensitivity (V _gl) and gain (V _bias), related to the perception of contrast and brightness, respectively, are adjusted manually on a handheld power supply device. Corneally recorded implant responses (CRIR) to full-field illumination with long duration flashes in various implant settings for brightness gain (V _bias) and amplifiers' sensitivity (V _gl) are measured using electroretinographic setup with a Ganzfeld bowl in a protocol of increasing stimulus luminances up to 1000 cd/m².

RESULTS

CRIRs are a meaningful tool for assessing the transfer characteristic curves of the electronic implant in vivo monitoring the implants' voltage output as a function of log luminance in a sigmoidal shape. Changing the amplifiers' sensitivity (V _gl) shifts the curve left or right along the log luminance axis. Adjustment of the gain (V _bias) changes the maximal output. Contrast perception is only possible within the luminance range of the increasing slope of the function.

CONCLUSIONS

The technical function of subretinal visual implants can be measured objectively using a standard electroretinographic setup. CRIRs help the patient to optimise the perception by adjusting the gain and luminance range of the device and are a useful tool for clinicians to objectively assess the function of subretinal visual implants in vivo.

ID: 106: ALVEOLAR ESCAPE BY BACILLUS ANTHRACIS SPORES DOES NOT REQUIRE A CARRIER CELL AND IS NOT ALTERED BY LETHAL TOXIN

Rationale

The lung is the entry site for Bacillus anthracis in inhalation anthrax, the most deadly form of the disease. B. anthracis spores must escape from the alveolus, pass to the regional lymph nodes, germinate and enter the circulatory system as vegetative bacteria to cause systemic disease. Of the resident lung cells, three have been reported to take up B. anthracis spores: the antigen presenting cells (APC) alveolar macrophages and dendritic cells, and alveolar epithelial cells (AEC). Also, B. anthracis produces the exotoxins lethal factor and protective antigen (PA) which combine to form lethal toxin (LT), a metalloproteinase important in pathogenicity. The roles of carrier cells and the effects of B. anthracis toxins in escape of spores from the alveolus are unclear, especially in humans.

Methods

We employed a human lung organ culture model and a human A549 alveolar epithelial cell culture model, along with fluorescent confocal imaging to quantitate spore partitioning between APC and AEC, and the effects of B. anthracis LT and PA on this process. Cell types were distinguished by positive staining for HLA-DR (APC) and cytokeratin (AEC).

Results

We found that spores progressed through the lung slice over time, and that spore movement was not dependent on cell internalization. Both free and cell-associated spores moved through slices between 2 and 48 hrs of incubation. However, partitioning of spores between AEC, APC, and the extracellular space did not significantly change over this time. After 2 hrs, 4.7% of spores were in APC; 13.8% in AEC; and 81.5% were not cell-associated. By 48 hrs, 2.9% were in APC; 12.7% were in AEC; and 84.4% were not cell-associated. Spores also internalized in a non-uniform manner, with more variable spore internalization into AEC than into APC. At all incubation times, the majority of cell-associated spores were in AEC, not in APC. PA and LT did not affect transit of the spores through the lung tissue or the distribution of spores into AEC and APC. In A549 cells, spore internalization increased significantly after 24 hrs incubation. However, there was no statistically consistent effects of PA or LT on spore internalization in A549 cells.

Conclusions

Overall, our results support a “Jailbreak”-like model of spore escape from the alveolus that involves transient passage of spores, although this occurs through intact AEC. However, subsequent transport of spores by APC from the lung to the lymph nodes may occur.

Reduced naïve CD8(+) T-cell priming efficacy in elderly adults

Aging is associated with impaired vaccine efficacy and increased susceptibility to infectious and malignant diseases. CD8⁺ T‐cells are key players in the immune response against pathogens and tumors. In aged mice, the dwindling naïve CD8⁺T‐cell compartment is thought to compromise the induction of de novo immune responses, but no experimental evidence is yet available in humans. Here, we used an original in vitro assay based on an accelerated dendritic cell coculture system in unfractioned peripheral blood mononuclear cells to examine CD8⁺ T‐cell priming efficacy in human volunteers. Using this approach, we report that old individuals consistently mount quantitatively and qualitatively impaired de novo CD8⁺ T‐cell responses specific for a model antigen. Reduced CD8⁺T‐cell priming capacity in vitro was further associated with poor primary immune responsiveness in vivo. This immune deficit likely arises as a consequence of intrinsic cellular defects and a reduction in the size of the naïve CD8⁺ T‐cell pool. Collectively, these findings provide new insights into the cellular immune insufficiencies that accompany human aging.

Pollen-derived nonallergenic substances enhance Th2-induced IgE production in B cells

BACKGROUND

B cells play a central role in IgE-mediated allergies. In damaged airway epithelium, they are exposed directly to aeroallergens. We aimed to assess whether direct exposure of B cells to pollen constituents affects allergic sensitization.

METHODS

B cells from murine splenocytes and from blood samples of healthy donors were incubated for 8 days under Th2-like conditions with aqueous ragweed pollen extracts (Amb-APE) or its constituents. Secreted total IgM, IgG, and IgE was quantified by ELISA. Additionally, birch, grass, or pine-pollen extracts were tested. The number of viable cells was evaluated by ATP measurements. B-cell proliferation was measured by CFSE staining. IgE class switch was analyzed by quantitation of class switch transcripts. In an OVA/Alum i.p.-sensitization mouse model, Amb-APE was intranasally instilled for 11 consecutive days.

RESULTS

Upon Th2 priming of murine B cells, ragweed pollen extract caused a dose-dependent increase in IgE production, while IgG and IgM were not affected. The low-molecular-weight fraction and phytoprostane E1 (PPE1) increased IgE production, while Amb a 1 did not. PPE1 enhanced IgE also in human memory B cells. Under Th1 conditions, Amb-APE did not influence immunoglobulin secretion. The IgE elevation was not ragweed specific. It correlated with proliferation of viable B cells, but not with IgE class switch. In vivo, Amb-APE increased total IgE and showed adjuvant activity in allergic airway inflammation.

CONCLUSIONS

Aqueous pollen extracts, the protein-free fraction of Amb-APE, and the pollen-contained substance PPE1 specifically enhance IgE production in Th2-primed B cells. Thus, pollen-derived nonallergenic substances might be responsible for B-cell-dependent aggravation of IgE-mediated allergies.

Adhesive luting of new CAD/CAM materials

OBJECTIVE

To evaluate the adhesive bonding performance of recently introduced tooth-colored CAD/CAM materials after different pretreatment protocols and using different luting materials.

MATERIALS AND METHODS

The CAD/CAM materials under investigation were e.max CAD (lithium disilicate glass ceramic; Ivoclar Vivadent, Schaan, Liechtenstein), Celtra Duo (zirconia-reinforced lithium disilicate ceramic; Dentsply DeTrey, Konstanz, Germany), Lava Ultimate (resin nano ceramic; 3M ESPE, Neuss, Germany), and Enamic (resin infiltrated ceramic; Vita, Bad Säckingen, Germany). A total of 240 blocks (n = 5) received various pretreatments (no pretreatment, silane, sandblasting, sandblasting + silane, hydrofluoric acid, hydrofluoric acid + silane), and then different classes of adhesive luting composites were applied (adhesive: Prime&Bond XP + SCA + Calibra; Dentsply DeTrey; self adhesive: RelyX Unicem; 3M ESPE). After 24 h water storage and 10,000 thermocycles (5°C/55°C), specimens were cut into beams and microtensile bond strengths were recorded.

RESULTS

Bonding performance of recent CAD/CAM materials was clearly influenced by the pretreatment method (P < 0.05). In general, significantly higher μ-TBS values were recorded for the ceramic materials compared to the hybrid materials (P < 0.05). Among the hybrid materials, Enamic exhibited higher bond strengths than Lava Ultimate (P < 0.05). However, despite the differences found, all materials showed a high level of bonding performance, being sufficient to withstand intraoral chewing forces during mastication.

CONCLUSION

When pretreated as recommended by the manufacturers, recent tooth-colored CAD/CAM materials show an encouraging bonding performance for adhesive luting.

Denosumab for the prevention of skeletal complications in metastatic castration-resistant prostate cancer: comparison of skeletal-related events and symptomatic skeletal events

In this analysis of a phase III trial in patients with castration-resistant prostate cancer and bone metastases, treatment with denosumab reduced the risk of skeletal complications vs zoledronic acid regardless of whether the end point was defined as SSE or SRE. Both SSEs and SREs were associated with development of moderate/severe pain among patients with no/mild pain at baseline.

Background

In a phase III trial in patients with castration-resistant prostate cancer (CRPC) and bone metastases, denosumab was superior to zoledronic acid in reducing skeletal-related events (SREs; radiation to bone, pathologic fracture, surgery to bone, or spinal cord compression). This study reassessed the efficacy of denosumab using symptomatic skeletal events (SSEs) as a prespecified exploratory end point.

Patients and methods

Patients with CRPC, no previous bisphosphonate exposure, and radiographic evidence of bone metastasis were randomized to subcutaneous denosumab 120 mg plus i.v. placebo every 4 weeks (Q4W), or i.v. zoledronic acid 4 mg plus subcutaneous placebo Q4W during the blinded treatment phase. SSEs were defined as radiation to bone, symptomatic pathologic fracture, surgery to bone, or symptomatic spinal cord compression. The relationship between SSE or SRE and time to moderate/severe pain was assessed using the Brief Pain Inventory Short Form.

Results

Treatment with denosumab significantly reduced the risk of developing first SSE [HR, 0.78; 95% confidence interval (CI) 0.66–0.93; P = 0.005] and first and subsequent SSEs (rate ratio, 0.78; 95% CI 0.65–0.92; P = 0.004) compared with zoledronic acid. The treatment differences in the number of patients with SSEs or SREs were similar (n = 48 and n = 45, respectively). Among patients with no/mild pain at baseline, both SSEs and SREs were associated with moderate/severe pain development (P < 0.0001). Fewer patients had skeletal complications, particularly fractures, when defined as SSE versus SRE.

Conclusion

In patients with CRPC and bone metastases, denosumab reduced the risk of skeletal complications versus zoledronic acid regardless of whether the end point was defined as SSE or SRE.