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Background:
From birth to young adulthood, health and development of young people are strongly linked to their living situation, including their family's socioeconomic position (SEP) and living environment. The impact of regional characteristics on development in early childhood beyond family SEP has been rarely investigated. This study aimed to identify regional predictors of global developmental delay at school entry taking family SEP into consideration.
Method:
We used representative, population-based data from mandatory school entry examinations of the German federal state of Brandenburg in 2018/2019 with n=22,801 preschool children. By applying binary multilevel models, we hierarchically analyzed the effect of regional deprivation defined by the German Index of Socioeconomic Deprivation (GISD) and rurality operationalized as inverted population density of the children's school district on global developmental delay (GDD) while adjusting for family SEP (low, medium and high)
Results:
Family SEP was significantly and strongly linked to GDD. Children with the highest family SEP showed a lower odds for GDD compared to a medium SEP (female: OR=4.26, male: OR=3.46) and low SEP (female: OR=16.58, male: OR=12.79). Furthermore, we discovered a smaller, but additional and independent effect of regional socioeconomic deprivation on GDD, with a higher odds for children from a more deprived school district (female: OR=1.35, male: OR=1.20). However, rurality did not show a significant link to GDD in preschool children beyond family SEP and regional deprivation.
Conclusion:
Family SEP and regional deprivation are risk factors for child development and of particular interest to promote health of children in early childhood and over the life course.
Sedentarism is a risk factor for depression and anxiety. People living with the human immunodeficiency virus (PLWH) have a higher prevalence of anxiety and depression compared to HIV-negative individuals. This cross-sectional study (n = 450, median age 44 (19-75), 7.3% females) evaluates the prevalence rates and prevalence ratio (PR) of anxiety and/or depression in PLWH associated with recreational exercise. A decreased likelihood of having anxiety (PR=0.57; 0.36-0.91; p = 0.01), depression (PR=0.41; 0.36-0.94; p=0.01), and comorbid anxiety and depression (PR = 0,43; 0.24-0.75; p=0.002) was found in exercising compared to non-exercising PLWH. Recreational exercise is associated with a lower risk for anxiety and/or depression. Further prospective studies are needed to provide insights on the direction of this association.
The investigation of protein structures, functions and interactions often requires modifications to adapt protein properties to the specific application. Among many possible methods to equip proteins with new chemical groups, the utilization of orthogonal aminoacyl-tRNA synthetase/tRNA pairs enables the site-specific incorporation of non-canonical amino acids at defined positions in the protein. The open nature of cell-free protein synthesis reactions provides an optimal environment, as the orthogonal components do not need to be transported across the cell membrane and the impact on cell viability is negligible. In the present work, it was shown that the expression of orthogonal aminoacyl-tRNA synthetases in CHO cells prior to cell disruption enhanced the modification of the pharmaceutically relevant adenosine A2a receptor. For this purpose, in complement to transient transfection of CHO cells, an approach based on CRISPR/Cas9 technology was selected to generate a translationally active cell lysate harboring endogenous orthogonal aminoacyl-tRNA synthetase.
Myasthenia gravis is an autoimmune disease affecting neuromuscular transmission and causing skeletal muscle weakness. Additionally, systemic inflammation, cognitive deficits and autonomic dysfunction have been described.
However, little is known about myasthenia gravis-related reorganization of the brain. In this study, we thus investigated the structural and functional brain changes in myasthenia gravis patients.
Eleven myasthenia gravis patients (age: 70.64 +/- 9.27; 11 males) were compared to age-, sex- and education-matched healthy controls (age: 70.18 +/- 8.98; 11 males). Most of the patients (n = 10, 0.91%) received cholinesterase inhibitors.
Structural brain changes were determined by applying voxel-based morphometry using high-resolution T-1-weighted sequences. Functional brain changes were assessed with a neuropsychological test battery (including attention, memory and executive functions), a spatial orientation task and brain-derived neurotrophic factor blood levels.
Myasthenia gravis patients showed significant grey matter volume reductions in the cingulate gyrus, in the inferior parietal lobe and in the fusiform gyrus. Furthermore, myasthenia gravis patients showed significantly lower performance in executive functions, working memory (Spatial Span, P = 0.034, d = 1.466), verbal episodic memory (P = 0.003, d = 1.468) and somatosensory-related spatial orientation (Triangle Completion Test, P = 0.003, d = 1.200).
Additionally, serum brain-derived neurotrophic factor levels were significantly higher in myasthenia gravis patients (P = 0.001, d = 2.040). Our results indicate that myasthenia gravis is associated with structural and functional brain alterations. Especially the grey matter volume changes in the cingulate gyrus and the inferior parietal lobe could be associated with cognitive deficits in memory and executive functions.
Furthermore, deficits in somatosensory-related spatial orientation could be associated with the lower volumes in the inferior parietal lobe. Future research is needed to replicate these findings independently in a larger sample and to investigate the underlying mechanisms in more detail.
Klaus et al. compared myasthenia gravis patients to matched healthy control subjects and identified functional alterations in memory functions as well as structural alterations in the cingulate gyrus, in the inferior parietal lobe and in the fusiform gyrus.
Coronary artery disease (CAD) is the leading cause of death worldwide.
Statins reduce morbidity and mortality of CAD. Intake of n-3 polyunsaturated fatty acid (n-3 PUFAs), particularly eicosapentaenoic acid (EPA), is associated with reduced morbidity and mortality in patients with CAD. Previous data indicate that a higher conversion of precursor fatty acids (FAs) to arachidonic acid (AA) is associated with increased CAD prevalence.
Our study explored the FA composition in blood to assess n-3 PUFA levels from patients with and without CAD. We analyzed blood samples from 273 patients undergoing cardiac catheterization. Patients were stratified according to clinically relevant CAD (n = 192) and those without (n = 81). FA analysis in full blood was performed by gas chromatography. Indicating increased formation of AA from precursors, the ratio of dihomo-gamma-linolenic acid (DGLA) to AA, the delta-5 desaturase index (D5D index) was higher in CAD patients. CAD patients had significantly lower levels of omega-6 polyunsaturated FAs (n-6 PUFA) and n-3 PUFA, particularly EPA, in the blood.
Thus, our study supports a role of increased EPA levels for cardioprotection.
Training intervention effects on cognitive performance and neuronal plasticity — A pilot study
(2022)
Studies suggest that people suffering from chronic pain may have altered brain plasticity, along with altered functional connectivity between pain-processing brain regions. These may be related to decreased mood and cognitive performance. There is some debate as to whether physical activity combined with behavioral therapy (e.g. cognitive distraction, body scan) may counteract these changes. However, underlying neuronal mechanisms are unclear. The aim of the current pilot study with a 3-armed randomized controlled trial design was to examine the effects of sensorimotor training for nonspecific chronic low back pain on (1) cognitive performance; (2) fMRI activity co-fluctuations (functional connectivity) between pain-related brain regions; and (3) the relationship between functional connectivity and subjective variables (pain and depression). Six hundred and sixty two volunteers with non-specific chronic low back pain were randomly allocated to a unimodal (sensorimotor training), multidisciplinary (sensorimotor training and behavioral therapy) intervention, or to a control group within a multicenter study. A subsample of patients (n = 21) from one study center participated in the pilot study presented here. Measurements were at baseline, during (3 weeks, M2) and after intervention (12 weeks, M4 and 24 weeks, M5). Cognitive performance was measured by the Trail Making Test and functional connectivity by MRI. Pain perception and depression were assessed by the Von Korff questionnaire and the Hospital and Anxiety. Group differences were calculated by univariate and repeated ANOVA measures and Bayesian statistics; correlations by Pearson's r. Change and correlation of functional connection were analyzed within a pooled intervention group (uni-, multidisciplinary group). Results revealed that participants with increased pain intensity at baseline showed higher functional connectivity between pain-related brain areas used as ROIs in this study. Though small sample sizes limit generalization, cognitive performance increased in the multimodal group. Increased functional connectivity was observed in participants with increased pain ratings. Pain ratings and connectivity in pain-related brain regions decreased after the intervention. The results provide preliminary indication that intervention effects can potentially be achieved on the cognitive and neuronal level. The intervention may be suitable for therapy and prevention of non-specific chronic low back pain.
Basic psychological needs theory postulates that a social environment that satisfies individuals’ three basic psychological needs of autonomy, competence, and relatedness leads to optimal growth and well-being. On the other hand, the frustration of these needs is associated with ill-being and depressive symptoms foremost investigated in non-clinical samples; yet, there is a paucity of research on need frustration in clinical samples. Survey data were compared between adult individuals with major depressive disorder (MDD; n = 115; 48.69% female; 38.46 years, SD = 10.46) with those of a non-depressed comparison sample (n = 201; 53.23% female; 30.16 years, SD = 12.81). Need profiles were examined with a linear mixed model (LMM). Individuals with depression reported higher levels of frustration and lower levels of satisfaction in relation to the three basic psychological needs when compared to non-depressed adults. The difference between depressed and non-depressed groups was significantly larger for frustration than satisfaction regarding the needs for relatedness and competence. LMM correlation parameters confirmed the expected positive correlation between the three needs. This is the first study showing substantial differences in need-based experiences between depressed and non-depressed adults. The results confirm basic assumptions of the self-determination theory and have preliminary implications in tailoring therapy for depression.
In recent years digital technologies have become a major means for providing health-related services and this trend was strongly reinforced by the current Coronavirus disease 2019 (COVID-19) pandemic. As it is well-known that regular physical activity has positive effects on individual physical and mental health and thus is an important prerequisite for healthy aging, digital technologies are also increasingly used to promote unstructured and structured forms of physical activity. However, in the course of this development, several terms (e.g., Digital Health, Electronic Health, Mobile Health, Telehealth, Telemedicine, and Telerehabilitation) have been introduced to refer to the application of digital technologies to provide health-related services such as physical interventions. Unfortunately, the above-mentioned terms are often used in several different ways, but also relatively interchangeably. Given that ambiguous terminology is a major source of difficulty in scientific communication which can impede the progress of theoretical and empirical research, this article aims to make the reader aware of the subtle differences between the relevant terms which are applied at the intersection of physical activity and Digital Health and to provide state-of-art definitions for them.
Brain activation during active balancing and its behavioral relevance in younger and older adults
(2022)
Age-related deterioration of balance control is widely regarded as an important phenomenon influencing quality of life and longevity, such that a more comprehensive understanding of the neural mechanisms underlying this process is warranted.
Specifically, previous studies have reported that older adults typically show higher neural activity during balancing as compared to younger counterparts, but the implications of this finding on balance performance remain largely unclear.
Using functional near-infrared spectroscopy (fNIRS), differences in the cortical control of balance between healthy younger (n = 27) and older (n = 35) adults were explored.
More specifically, the association between cortical functional activity and balance performance across and within age groups was investigated. To this end, we measured hemodynamic responses (i.e., changes in oxygenated and deoxygenated hemoglobin) while participants balanced on an unstable device.
As criterion variables for brain-behavior-correlations, we also assessed postural sway while standing on a free-swinging platform and while balancing on wobble boards with different levels of difficulty.
We found that older compared to younger participants had higher activity in prefrontal and lower activity in postcentral regions.
Subsequent robust regression analyses revealed that lower prefrontal brain activity was related to improved balance performance across age groups, indicating that higher activity of the prefrontal cortex during balancing reflects neural inefficiency.
We also present evidence supporting that age serves as a moderator in the relationship between brain activity and balance, i.e., cortical hemodynamics generally appears to be a more important predictor of balance performance in the older than in the younger. Strikingly, we found that age differences in balance performance are mediated by balancing-induced activation of the superior frontal gyrus, thus suggesting that differential activation of this region reflects a mechanism involved in the aging process of the neural control of balance.
Our study suggests that differences in functional brain activity between age groups are not a mere by-product of aging, but instead of direct behavioral relevance for balance performance.
Potential implications of these findings in terms of early detection of fall-prone individuals and intervention strategies targeting balance and healthy aging are discussed.
In recent years digital technologies have become a major means for providing health-related services and this trend was strongly reinforced by the current Coronavirus disease 2019 (COVID-19) pandemic. As it is well-known that regular physical activity has positive effects on individual physical and mental health and thus is an important prerequisite for healthy aging, digital technologies are also increasingly used to promote unstructured and structured forms of physical activity. However, in the course of this development, several terms (e.g., Digital Health, Electronic Health, Mobile Health, Telehealth, Telemedicine, and Telerehabilitation) have been introduced to refer to the application of digital technologies to provide health-related services such as physical interventions. Unfortunately, the above-mentioned terms are often used in several different ways, but also relatively interchangeably. Given that ambiguous terminology is a major source of difficulty in scientific communication which can impede the progress of theoretical and empirical research, this article aims to make the reader aware of the subtle differences between the relevant terms which are applied at the intersection of physical activity and Digital Health and to provide state-of-art definitions for them.
Basic psychological needs theory postulates that a social environment that satisfies individuals’ three basic psychological needs of autonomy, competence, and relatedness leads to optimal growth and well-being. On the other hand, the frustration of these needs is associated with ill-being and depressive symptoms foremost investigated in non-clinical samples; yet, there is a paucity of research on need frustration in clinical samples. Survey data were compared between adult individuals with major depressive disorder (MDD; n = 115; 48.69% female; 38.46 years, SD = 10.46) with those of a non-depressed comparison sample (n = 201; 53.23% female; 30.16 years, SD = 12.81). Need profiles were examined with a linear mixed model (LMM). Individuals with depression reported higher levels of frustration and lower levels of satisfaction in relation to the three basic psychological needs when compared to non-depressed adults. The difference between depressed and non-depressed groups was significantly larger for frustration than satisfaction regarding the needs for relatedness and competence. LMM correlation parameters confirmed the expected positive correlation between the three needs. This is the first study showing substantial differences in need-based experiences between depressed and non-depressed adults. The results confirm basic assumptions of the self-determination theory and have preliminary implications in tailoring therapy for depression.
Background
Ankle sprain is the most common injury in basketball. Chronic ankle instability develops from an acute ankle sprain may cause negative effects on quality of life, ankle functionality or on increasing risk for recurrent ankle sprains and post-traumatic osteoarthritis. To facilitate a preventative strategy of chronic ankle instability (CAI) in the basketball population, gathering epidemiological data is essential. However, the epidemiological data of CAI in basketball is limited. Therefore, this study aims to investigate the prevalence of CAI in basketball athletes and to determine whether gender, competitive level, and basketball playing position influence this prevalence.
Methods
In a cross-sectional study, in total 391 Taiwanese basketball athletes from universities and sports clubs participated. Besides non-standardized questions about demographics and their history of ankle sprains, participants further filled out the standard Cumberland Ankle Instability Tool applied to determine the presence of ankle instability. Questionnaires from 255 collegiate and 133 semi-professional basketball athletes (male = 243, female = 145, 22.3 ± 3.8 years, 23.3 ± 2.2 kg/m2) were analyzed. Differences in prevalence between gender, competitive level and playing position were determined using the Chi-square test.
Results
In the surveyed cohort, 26% had unilateral CAI while 50% of them had bilateral CAI. Women had a higher prevalence than men in the whole surveyed cohort (X2(1) = 0.515, p = 0.003). This gender disparity also showed from sub-analyses, that the collegiate female athletes had a higher prevalence than collegiate men athletes (X2(1) = 0.203, p = 0.001). Prevalence showed no difference between competitive levels (p > 0.05) and among playing positions (p > 0.05).
Conclusions
CAI is highly prevalent in the basketball population. Gender affects the prevalence of CAI. Regardless of the competitive level and playing position the prevalence of CAI is similar. The characteristic of basketball contributes to the high prevalence. Prevention of CAI should be a focus in basketball. When applying the CAI prevention measures, gender should be taken into consideration.
Background
Ankle sprain is the most common injury in basketball. Chronic ankle instability develops from an acute ankle sprain may cause negative effects on quality of life, ankle functionality or on increasing risk for recurrent ankle sprains and post-traumatic osteoarthritis. To facilitate a preventative strategy of chronic ankle instability (CAI) in the basketball population, gathering epidemiological data is essential. However, the epidemiological data of CAI in basketball is limited. Therefore, this study aims to investigate the prevalence of CAI in basketball athletes and to determine whether gender, competitive level, and basketball playing position influence this prevalence.
Methods
In a cross-sectional study, in total 391 Taiwanese basketball athletes from universities and sports clubs participated. Besides non-standardized questions about demographics and their history of ankle sprains, participants further filled out the standard Cumberland Ankle Instability Tool applied to determine the presence of ankle instability. Questionnaires from 255 collegiate and 133 semi-professional basketball athletes (male = 243, female = 145, 22.3 ± 3.8 years, 23.3 ± 2.2 kg/m2) were analyzed. Differences in prevalence between gender, competitive level and playing position were determined using the Chi-square test.
Results
In the surveyed cohort, 26% had unilateral CAI while 50% of them had bilateral CAI. Women had a higher prevalence than men in the whole surveyed cohort (X2(1) = 0.515, p = 0.003). This gender disparity also showed from sub-analyses, that the collegiate female athletes had a higher prevalence than collegiate men athletes (X2(1) = 0.203, p = 0.001). Prevalence showed no difference between competitive levels (p > 0.05) and among playing positions (p > 0.05).
Conclusions
CAI is highly prevalent in the basketball population. Gender affects the prevalence of CAI. Regardless of the competitive level and playing position the prevalence of CAI is similar. The characteristic of basketball contributes to the high prevalence. Prevention of CAI should be a focus in basketball. When applying the CAI prevention measures, gender should be taken into consideration.
Kraft und Kognition
(2023)
Die in den letzten Jahren aus Querschnittstudien gewonnenen empirischen Erkenntnisse deuten auf einen Zusammenhang zwischen muskulärer Kraftleistungsfähigkeit und kognitiver Leistungsfähigkeit hin [10]. Diese Beobachtung wird von Längsschnittstudien gestützt, bei denen in Folge gezielter Krafttrainingsinterventionen, welche typischerweise zur Steigerung der muskulären Kraftleistungsfähigkeit führen, Verbesserungen der kognitiven Leistungsfähigkeit dokumentiert werden konnten [11]. Die zugrundeliegenden Mechanismen, die den Zusammenhang zwischen muskulärer Kraftleistungsfähigkeit und kognitiver Leistungsfähigkeit begründen, sind jedoch noch nicht vollständig bekannt und bedürfen weiterer Forschung [10,12]. Vor diesem Hintergrund hatten die im Rahmen dieser Dissertation durchgeführten Forschungsarbeiten das übergeordnete Ziel, die Mechanismen zu untersuchen, welche den Zusammenhang zwischen der muskulären Kraftleistungsfähigkeit und der kognitiven Leistungsfähigkeit erklären können. In dieser Arbeit wurden dazu unterschiedliche Populationen (junge Menschen und ältere Menschen ohne und mit leichten kognitiven Störungen) unter Anwendung verschiedener untersuchungsmethodischer Ansätze (systematische Literaturrecherche, Doppelaufgabenparadigma und funktionelle Nahinfrarotspektroskopie) untersucht. Aufgrund der im Rahmen dieser Dissertation durchgeführten Forschungsarbeiten, die konsekutiv aufeinander aufbauen, konnten folgende Haupterkenntnisse gewonnen werden:
• Um einen umfassenden Überblick über die aktuelle Evidenzlage zum Thema Kraftleistungsfähigkeit und kognitiver Leistungsfähigkeit sowie den zugrundeliegenden neuronalen Korrelaten zu erlangen, wurde eine systematische Literaturrecherche zu diesem Forschungsthema durchgeführt. Die Ergebnisse dieser systematischen Literaturrecherche dokumentieren, dass ein gezieltes Krafttraining neben der Steigerung der kognitiven Leistungsfähigkeit zu funktionellen und strukturellen Veränderungen des Gehirns, insbesondere in frontalen Gehirnregionen, führen kann [13]. Ferner zeigen die Ergebnisse dieser systematischen Literaturrecherche, bei der eine begrenzte Anzahl verfügbarer Studien (n = 18) identifiziert wurde, den Bedarf weiterer Forschungsarbeiten zu diesem Themenfeld an [13].
• Zur Überprüfung der Hypothese, dass zur Ausführung von Krafttrainingsübungen höhere kognitive Prozesse benötigt werden, wurde in einer experimentellen Studie bei jüngeren gesunden Erwachsenen das Doppelaufgabenparadigma bei der Krafttrainingsübung Knie-beuge angewendet. Die in dieser Studie beobachteten Doppelaufgabenkosten bei der Ausführung der Krafttrainingsübung Kniebeuge (im Vergleich zur Kontrollbedingung Stehen) deuten auf die Beteiligung höherer kognitiver Prozesse zur Lösung dieser Bewegungsaufgabe hin und bestätigen die aufgestellte Hypothese [14].
• Um die Hypothese zu untersuchen, dass spezifische neuronale Korrelate (funktionelle Gehirnaktivität) den Zusammenhang zwischen muskulärer Kraftleistungsfähigkeit und kognitiver Leistungsfähigkeit vermitteln, wurde bei jungen gesunden Erwachsenen der Zusammenhang zwischen der Ausprägung der maximalen Handgriffkraft (normalisiert auf den Body-Mass-Index) und der kortikalen hämodynamischen Antwortreaktion untersucht, die bei der Durchführung eines standardisierten kognitiven Tests mittels funktioneller Nahinfrarotspektroskopie in präfrontalen Gehirnarealen gemessen wurde. Im Rahmen dieser Querschnittsstudie konnte die initiale Hypothese nicht vollständig bestätigt werden, da zwar Zusammenhänge zwischen maximaler Handgriffkraft und kognitiver Leistungsfähigkeit mit Parametern der hämodynamischen Antwortreaktion beobachtet wurden, aber die Ausprägung der maximalen Handgriffkraft nicht im Zusammenhang mit der Kurzeitgedächtnisleistung stand [16].
• Zur Untersuchung der Annahme, dass eine vorliegende neurologische Erkrankung (im Speziellen eine leichte kognitive Störung), die typischerweise mit Veränderungen von spezifischen neuronalen Korrelaten (z.B. des Hippokampus‘ [17-19] und des präfrontalen Kortex‘ [20,21]) einhergeht, einen Einfluss auf die Assoziation zwischen muskulärer Kraftleistungsfähigkeit und kognitiver Leistungsfähigkeit hat, wurde in einer Querschnittsstudie der Zusammenhang zwischen der Ausprägung der maximalen Handgriffkraft (normalisiert auf den Body-Mass-Index) und der Ausprägung der exekutiven Funktionen bei älteren Erwachsenen mit amnestischem und nicht-amnestischem Subtyp der leichten kognitiven Störung sowie gesunden älteren Erwachsenen untersucht. In dieser Querschnittsstudie wurde nur bei älteren Erwachsenen mit dem amnestischen Subtyp der leichten kognitiven Störung ein Zusammenhang zwischen maximaler Handgriffkraft und exekutiven Funktionen beobachtet. Solch eine Korrelation existiert jedoch nicht bei älteren Erwachsenen mit dem non-amnestischen Subtyp der leichten kognitiven Störung oder bei gesunden älteren Erwachsenen [24].
• In einem Perspektivenartikel wurde aufgezeigt, wie durch die theoriegeleitete Nutzung physiologischer Effekte, die bei einer speziellen Krafttrainingsmethode durch die Moderation des peripheren Blutflusses mittels Manschetten oder Bändern auftreten, insbesondere Populationen mit niedriger mechanischer Belastbarkeit von den positiven Effekten des Krafttrainings auf die Gehirngesundheit profitieren könnten [25].
Insgesamt deuten die Ergebnisse der in dieser Dissertation zusammengeführten und aufeinander aufbauenden Forschungsarbeiten auf das Vorhandensein von gemeinsamen neuronalen Korrelaten (z.B. frontaler Kortex) hin, die sowohl für die muskuläre Kraftleistungsfähigkeit als auch für höhere kognitive Prozesse eine wichtige Rolle spielen [26]. Betrachtet man die in der vorliegenden Dissertation gewonnenen Erkenntnisse im Verbund mit den bereits in der Literatur existieren-den empirischen Belegen, unterstützen sie die Sichtweise, dass eine relativ hohe muskuläre Kraftleistungsfähigkeit und deren Erhalt durch gezielte Krafttrainingsinterventionen über die Lebenspanne positive Effekte auf die (Gehirn-)Gesundheit haben können [27].
Background: The characteristics of osteoporosis are decreased bone mass and destruction towards the microarchitecture of bone tissue, which raises the risk of fracture. Psychosocialstress and osteoporosis are linked by sympathetic nervous system, hypothalamic-pituitary-adrenal axis, and other endocrine factors. Psychosocial stress causes a series of effects on the organism, and this long-term depletion at the cellular level is considered to be mitochondrial allostatic load, including mitochondrial dysfunction and oxidative stress. Extracellular vesicles (EVs) are involved in the mitochondrial allostatic load process and may as biomarkers in this setting. As critical participants during cell-to-cell communications, EVs serve as transport vehicles for nucleic acid and proteins, alter the phenotypic and functional characteristics of their target cells, and promote cell-to-cell contact. And hence, they play a significant role in the diagnosis and therapy of many diseases, such as osteoporosis.
Aim: This narrative review attempts to outline the features of EVs, investigate their involvement in both psychosocial stress and osteoporosis, and analyze if EVs can be potential mediators between both.
Methods: The online database from PubMed, Google Scholar, and Science Direct were searched for keywords related to the main topic of this study, and the availability of all the selected studies was verified. Afterward, the findings from the articles were summarized and synthesized.
Results: Psychosocial stress affects bone remodeling through increased neurotransmitters such as glucocorticoids and catecholamines, as well as increased glucose metabolism. Furthermore, psychosocial stress leads to mitochondrial allostatic load, including oxidative stress, which may affect bone remodeling. In vitro and in vivo data suggest EVs might involve in the link between psychosocial stress and bone remodeling through the transfer of bioactive substances and thus be a potential mediator of psychosocial stress leading to osteoporosis.
Conclusions: According to the included studies, psychosocial stress affects bone remodeling, leading to osteoporosis. By summarizing the specific properties of EVs and the function of EVs in both psychosocial stress and osteoporosis, respectively, it has been demonstrated that EVs are possible mediators of both, and have the prospects to be useful in innovative research areas.
Die interventionelle Behandlung des Vorhofflimmerns verursacht häufiger als in der Vergangenheit wahrgenommen eine Beeinträchtigung benachbarter Gewebe und Organe. Im Vordergrund der Betrachtungen dieser Arbeit stehen Schäden des Oesophagus, die aufgrund der schlechten Vorhersagbarkeit, des zeitlich verzögerten Auftretens und der fatalen Prognose bei Ausbildung einer atrio-oesophagealen Fistel besondere Relevanz haben.
Das Vorhofflimmern selbst ist nicht mit einer unmittelbaren vitalen Bedrohung verbunden, aber durch seine Komplikationen (z.B. Herzinsuffizienz, Schlaganfall) dennoch prognostisch relevant. Durch Antiarrhythmika gelingt keine Verbesserung der Rhythmuskontrolle (Arrhythmie-Freiheit), eine katheterinterventionelle Behandlung ist der medikamentösen Therapie überlegen. Durch eine frühzeitige und erfolgreiche Behandlung des Vorhofflimmerns konnte eine Verbesserung klinischer Endpunkte und der Prognose erreicht werden. Das Risiko einer invasiven Behandlung (insbesondere hinsichtlich des Auftretens prognoserelevanter Komplikationen) muss jedoch bei der Indikationsstellung und der Prozedur-Durchführung bedacht und gegenüber den günstigen Effekten der Behandlung abgewogen werden.
Untersuchungen zur Vermeidung der sehr seltenen atrio-oesophagealen Fisteln bedienen sich Surrogat-Parametern, hier bisher ausschließlich den ablationsinduzierten Schleimhaut-Läsionen des Oesophagus. Die Untersuchungen dieser Arbeit zeigen ein komplexeres Bild der (peri)-oesophagealen Schädigungen nach Vorhofflimmern-Ablation mit thermischen Energiequellen.
(1) Neue Definition der Oesophagus-Schäden: Oesophageale und perioesophageale Beeinträchtigungen treten sehr häufig auf (nach der hier verwendeten erweiterten Definition bei zwei Drittel der Patienten) und sind unabhängig von der verwendeten Ablationsenergie. Unterschiede finden sich in den Manifestationen der Oesophagus-Schäden für die verschiedenen Energie-Protokolle, ohne dass der Mechanismus hierfür aufgeklärt ist. Diese Arbeit beschreibt die unterschiedlichen Ausprägungen thermischer Oesophagus-Schäden, deren Determinanten und pathophysiologische Relevanz.
(2) Die Detektion (zum Teil subtiler) Oesophagus-Schäden ist maßgeblich von der Intensität der Nachsorge abhängig. Eine Beschränkung auf subjektive Schilderungen (z.B. Schmerzen beim Schluckakt, Sodbrennen) ist irreführend, die Mehrzahl der Veränderungen bleibt asymptomatisch, die Symptome der ausgebildeten atrio-oesophagealen Fistel (meist nach mehreren Wochen) bereits mit einer sehr schlechten Prognose belastet. Eine Endoskopie der Speiseröhre findet in den meisten elektrophysiologischen Zentren nicht oder nur bei anhaltenden Symptomen statt und kann ausschließlich Mukosa-Läsionen nachweisen. Damit wird das Ausmaß des oesophagealen und perioesophagealen Schadens bei Weitem unterschätzt. Veränderungen des perioesophagealen Raums, deren klinische Relevanz (noch) unklar ist, werden nicht erfasst, und damit ein Wandödem und Schäden im Gewebe zwischen linkem Vorhof und Speiseröhre (einschl. Nerven und Gefäßen) ignoriert.
Die Studien tragen auch zur Neubewertung etablierter Messgrößen und Risikofaktoren der Oesophagus-Schäden bei.
(3) Das Temperaturmonitoring im Oesophagus anhand der Maximalabweichungen ist erst für Extremwerte aussagekräftig und dadurch nicht hilfreich, Oesophagus-Läsionen zu vermeiden. Die komplexe Analyse der Temperatur-Rohdaten (bisher nur offline möglich) liefert in der AUC für RF-Ablationen einen prädiktiven Parameter für Oesophagus-Schäden, der eine Strukturierung der weiteren endoskopischen Diagnostik erlaubt. Ein vergleich¬barer Wert für die Cryoablationen konnte in den Analysen nicht gefunden werden.
(4) Eine chronische Entzündung des unteren Oesophagus-Drittels behindert nicht nur das Abheilen einer thermischen Oesophagus-Läsion, sondern kann das Auftreten solcher Läsionen durch die Ablation begünstigen. Die große Zahl vorbestehender Oesophagus-Veränderungen, die eine erhöhte Vulnerabilität anzeigen, und die Bedeutung für die Ent¬stehung thermischer Läsionen können der Ansatzpunkt präventiver Maßnahmen sein.
Ergänzend werden Ausprägungen der Oesophagus-Schäden durch umfangreiche Diagnostik erfasst und beschrieben, die aus pathophysiologischen Überlegungen relevant sein können.
(5) Die systematische Erweiterung der bildgebenden Diagnostik auf den perioesophagealen Raum durch Endosonographie zeigte, dass Schleimhaut-Läsionen alleine nur einen geringen Teil der Oesophagus-Schäden darstellen. Schleimhaut-Läsionen infolge einer instrumentellen Verletzung sind nicht mit dem Risiko der Ausbildung einer atrio-oesophagealen Fistel verbunden und unterstreichen die pathophysiologische Relevanz der perioesophagealen Veränderungen.
(6) Eine funktionelle Diagnostik thermischer Schäden des perioesophagealen Vagus-Plexus identifiziert Patienten mit Oesophagus-Schäden, die bildgebend nicht erfasst wurden, jedoch in ihren Auswirkungen (Nahrungsretention und gastro-oesophagealer Reflux) zur Läsionsprogression beitragen können.