Infrared reflection absorption spectroscopy (IRRAS) of the highly symmetric molecules C2H4 and C2H6 adsorbed as mono- and multilayers onto copper films is studied in relation to the type of ...metal-film roughness. Spectra of C2H4 show Raman lines on cold-deposited Cu films but not on Cu deposited at room temperature. For C2H6, the IR spectra from both types of metal films are similar; the surface infrared selection rule holds and no Raman bands are observed. The Raman lines that appear in the IR spectra already at low exposures are attributed to species adsorbed at special defect sites, identical to the so-called active sites in surface enhanced Raman scattering (SERS). The IR excitation mechanism by transient electron transfer to the adsorbate π* state can deliver a discrete vibrational band of a Raman-active vibration only under certain circumstances, for example, for adsorbates at the “SERS-active sites”. C2H6 at these sites cannot deliver Raman bands in IRRAS, because it has no π* state. We also discuss IRRAS measurements on Cu(111) and Cu(110) single crystals, where Raman bands of C2H4 have been observed.
Alzheimer’s disease (AD) is a pervasive and progressive neurodegenerative disorder characterized by a gradual decline in memory, leading to significant impairments in cognition, language, and social ...functioning. An early-onset variant of the disease is a substantial source of morbidity in individuals with trisomy 21, the main cause of Down syndrome (DS), with clinical evidence of the disease seen in roughly one-half of those 50 years and older. Current pharmacologic therapies are limited to a handful of medications that offer only modest improvement in cognition and overall functioning. There is growing consensus in the literature that lithium salts, well-established as efficacious in the treatment of select affective disorders, may also provide neuroprotection from the development and progression of AD by targeting multiple processes implicated in the disease. These include beta-amyloid production, tau hyperphosphorylation, mitochondrial dysfunction, oxidative stress, and neuroinflammation. While complex, inhibition of glycogen synthase kinase 3 (GSK-3) appears to be the primary mechanism by which lithium exerts its disease-modifying effects. Reduced rates of dementia have been described in bipolar patients chronically treated with lithium. Additionally, “micro-dose” lithium (300 µg daily in one study) demonstrated stabilization of cognitive decline in AD patients with mild cognitive impairment. With encouraging data suggesting that lithium confers a clinically significant benefit in AD by impeding accumulation of the aberrant proteins central to the putative pathogenesis, it follows to reason that a population with a genetic predisposition rooted in this disease mechanism may benefit from it. After a thorough review of the literature and currently active clinical trials, no studies have looked at using lithium to slow or prevent the development of Alzheimer’s disease in the Down syndrome population. Because those with DS have such reliably high rates of developing AD, many 20–30 years younger than those in the general population, they represent an exemplary subject population to investigate the effect that lithium has on progression to disease. Furthermore, the specific factors that make those with Down syndrome prone to developing AD, including enhanced ability to synthesize beta-amyloid, mitochondrial dysfunction, and elevated oxidative stress, correlate quite well with the model by which lithium is thought to disrupt Alzheimer’s pathogenesis, making the DS population ideally suited to study this intervention. Demonstrating reduced progression of Alzheimer’s pathology with micro-dose lithium in those with trisomy 21 could function to reinforce our current understanding of the pathogenetic mechanism underlying early-onset AD, and ultimately, establish a preventative treatment for the disease.
Abstract
Situationally induced optimism has been shown to influence several components of experimental pain. The aim of the present study was to enlarge these findings for the first time to the ...earliest components of the pain response by measuring contact heat evoked potentials (CHEPs) and the sympathetic skin response (SSR). Forty-seven healthy participants underwent two blocks of phasic thermal stimulation. CHEPs, the SSR and self-report pain ratings were recorded. Between the blocks of stimulation, the ‘Best Possible Self’ imagery and writing task was performed to induce situational optimism. The optimism manipulation was successful in increasing state optimism. It did, however, neither affect pain-evoked potentials nor the SSR nor self-report pain ratings. These results suggest that optimism does not alter early responses to pain. The higher-level cognitive processes involved in optimistic thinking might only act on later stages of pain processing. Therefore, more research is needed targeting different time frames of stimulus processing and response measures for early and late pain processing in parallel.
Non-specific low back pain (LBP) is one of the leading causes of global disability. Multidisciplinary pain treatment (MPT) programs comprising educational, physical, and psychological interventions ...have shown positive treatment effects on LBP. Nonetheless, such programs are costly and treatment opportunities are often limited to specialized medical centers. mHealth and other digital interventions may be a promising method to successfully support patient self-management in LBP. To address these issues, we investigated the clinical effects of a multidisciplinary mHealth back pain App (Kaia App) in a randomized controlled trial (registered at German Clinical Trials Register under DRKS00016329). One-hundred one adult patients with non-specific LBP from 6 weeks to 1 year were randomly assigned to an intervention group or a control group. In the intervention group, the Kaia App was provided for 3 months. Control treatment consisted of six individual physiotherapy sessions over 6 weeks and high-quality online education. The primary outcome, pain intensity, was assessed at 12-week follow-up on an 11-point numeric rating scale (NRS). Our per-protocol analysis showed no significant differences between the groups at baseline (Kaia App group:
= 5.10 (SD = 1.07) vs. control group:
= 5.41 (SD = 1.15). At 12-week follow-up the Kaia App group reported significantly lower pain intensity (
= 2.70 (SD = 1.51)) compared to the control group (
= 3.40 (SD = 1.63)). Our results indicate that the Kaia App as a multidisciplinary back pain app is an effective treatment in LBP patients and is superior to physiotherapy in combination with online education.
In this paper we describe the development of a shear horizontal surface acoustic wave immunosensor for medical diagnostics. There exists a strong interest in the rapid detection of antigen–antibody ...reactions at small concentrations in the
μ
g/ml region in plasma, serum, or whole blood. Sensors whose operating principle is based on shear horizontal acoustic surface waves are well suited for this. We have used a spin-on glass film for the guidance of the surface wave as well as for the protection of the aluminum structures of the surface wave transducers from aggressive analyte liquids. This film has proven to considerably enhance the sensitivity of the device, and to simultaneously provide a durable protection of the transducers. Furthermore, polymers based on polyvinylamines have been used for the first time for immobilization of the capture protein. This technique effectively prevents the undesired binding of foreign substances like cells, non-specific antibodies, or other proteins at the sensor surface.
Abstract Hypomimia which refers to a reduced degree in facial expressiveness is a common sign in Parkinson's disease (PD). The objective of our study was to investigate how hypomimia affects PD ...patients' facial expression of pain. The facial expressions of 23 idiopathic PD patients in the Off-phase (without dopaminergic medication) and On-phase (after dopaminergic medication intake) and 23 matched controls in response to phasic heat-pain and a temporal summation procedure were recorded and analyzed for overall and specific alterations using the Facial Action Coding System (FACS). We found reduced overall facial activity in response to pain in PD patients in the Off which was less pronounced in the On. Especially the highly pain-relevant eye-narrowing occurred less frequently in PD patients than in controls in both phases while frequencies of other pain-relevant movements, like upper lip raise (in the On) and contraction of the eyebrows (in both phases), did not differ between groups. Moreover, opening of the mouth (which is often not considered as pain-relevant) was the most frequently displayed movement in PD patients, whereas eye-narrowing was the most frequent movement in controls. Not only overall quantitative changes in the degree of facial pain expressiveness occurred in PD patients but also qualitative changes were found. The latter refer to a strongly affected encoding of the sensory dimension of pain (eye-narrowing) while the encoding of the affective dimension of pain (contradiction of the eyebrows) was preserved. This imbalanced pain signal might affect pain communication and pain assessment.
Abstract Objective. Nociceptive abnormalities indicating increased pain sensitivity have been reported in patients with Parkinson's disease (PD). The disturbances are mostly responsive to ...dopaminergic (DA) treatment; yet, there are conflicting results. The objective of the present study was to investigate pain processing and nociception in PD patients in a more comprehensive manner than previous studies. For this purpose, a multi-methods approach was used in order to monitor different levels of the central nervous system (spinal, subcortical-vegetative, cortical). Methods The heat-pain threshold, contact-heat evoked brain potentials (CHEPs) and sympathetic skin responses (SSR), nociceptive flexion responses (NFR) and subjective pain ratings were measured in 23 idiopathic PD patients both in the Off-phase (without DA medication) and On-phase (after DA medication intake) as well as in 23 healthy controls. Results Compared to controls, PD patients showed decreased heat-pain thresholds only in the Off and tentatively increased NFR amplitudes in both phases. We found no between-group differences for the CHEPs, the NFR threshold/latency or the pain ratings. Yet, SSR amplitudes/frequencies were decreased and latencies were increased in PD patients in both phases. Correlations between CHEPs amplitudes and pain ratings were found only in controls. Discussion Increased pain sensitivity (heat-pain threshold) in the Off which normalizes in the On argues for DA induced dysfunctions of the nigrostriatal pain loops with the basal ganglia as main circuit in our PD sample. Dysfunctions of the subcortical-vegetative parameters despite of inconspicuous cortical nociception suggest disturbances of the central or peripheral innervation of sympathetic branches with coincidently intact ascending pathways in the PD group.
In recent years the association of conditioned pain modulation (CPM) with trait fear and anxiety has become a hot topic in pain research due to the assumption that such variables may explain the low ...CPM efficiency in some individuals. However, empirical evidence concerning this association is still equivocal. Our study is the first to investigate the predictive power of fear and anxiety for CPM by using a well-established psycho-physiological measure of trait fear, i.e. startle potentiation, in addition to two self-report measures of pain-related trait anxiety. Forty healthy, pain-free participants (female:
N
= 20; age:
M
= 23.62 years) underwent two experimental blocks in counter-balanced order: (1) a startle paradigm with affective picture presentation and (2) a CPM procedure with hot water as conditioning stimulus (CS) and contact heat as test stimulus (TS). At the end of the experimental session, pain catastrophizing (PCS) and pain anxiety (PASS) were assessed. PCS score, PASS score and startle potentiation to threatening pictures were entered as predictors in a linear regression model with CPM magnitude as criterion. We were able to show an inhibitory CPM effect in our sample: pain ratings of the heat stimuli were significantly reduced during hot water immersion. However, CPM was neither predicted by self-report of pain-related anxiety nor by startle potentiation as psycho-physiological measure of trait fear. These results corroborate previous negative findings concerning the association between trait fear/anxiety and CPM efficiency and suggest that shifting the focus from trait to state measures might be promising.
Digital medicine has increasing influence on the German healthcare system. In times of social distancing during the ongoing coronavirus disease 2019 (COVID-19) pandemic, digital tools enable health ...professionals to maintain medical care. Furthermore, digital elements have potential to provide effective guideline-oriented treatment to a broad range of patients independently from location and time. This survey was used to assess the attitudes of members of the German Pain Society (health professionals) and of associated self-help groups (patients) towards digital medicine. It was sent out as an online survey to health professionals in September 2020 and to patients in February 2021. The survey referred especially to present usage, attitude and potential concerns regarding particular digital elements. Furthermore, technical affinity was assessed. In total, 250 health professionals and 154 patients participated in the survey. The results show that-although digital elements are already known-a substantial proportion of health professionals still lack broad transfer to regular treatment. The potential of digital tools seems to be recognized by both groups; interestingly, patients consider digital medicine as more useful than health professionals. Nevertheless, concerns about for example data security or digital competence remain in both groups. Taken together, our results indicate that disruptive changes, as the implementation of digital medicine in the healthcare system, have to be guided by intense education and channeled by political policies in order to successfully integrate digital elements into medicine on a long-term basis. This would be in favor for all involved parties and is demanded especially by patients.
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