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Communication with cancer patients: the perspective of caregivers versus non-caregivers in Iran
No full textObjective: This study investigated and compared the attitudes of healthy Iranian
individuals (n = 302) in forms of two groups of caregivers and non-caregivers of
cancer patients about the communication with cancer patients, and their personal
wish to know the diagnosis if they ever had cancer. In addition, this study aimed
to identify how many participants in the caregivers’ group had spoken with their
family member affected by cancer about their illness.
Methods: Caregivers (50.7%) and non-caregivers (49.3%) responded to two
questionnaires regarding their general attitudes about communicating with
cancer patients, and their willingness to know about their illness if they had cancer.
Results: The majority of participants (92.8%), especially in the caregiver group,
agreed with the right of patients to know the diagnosis and prognosis, and also
wished to know if they ever had cancer. However, around 64% of caregivers never
talked about cancer with the affected patients.
Conclusion: Participants generally believed that patients have the right to know
the diagnosis and prognosis, and they also wished to know if they ever had cancer.
However, in reality many cancer patients are not included in communication
sessions in Iran. Health professionals should focus on how to create a balance
between medical bioethics with cultural influences on communication with
patients.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Experimental Evidence on Forecaster (anti-) Herding in Sports Markets
No full textWe experimentally analyzed whether (anti-)herding behavior of forecasters in sport-betting markets is influenced by the incentive structure of the market (winner-takes-all vs. equal payment of most accurate forecasts) and by personal traits of forecasters. We found evidence of anti-herding in forecasts of the German Bundesliga. Self-reported knowledge and, more surprisingly, winner-takes-all incentives reduced anti-herding. On average, forecasts were less accurate with stronger anti-herding. Winner-takes-all incentives and self-reported knowledge improved forecasts
Standing and “Survival” in the Adult Film Industry
No full textIt is said that knowing the right people is essential for one’s career, which is supported in the literature on social capital. However, the empirical evidence in this field remains ambiguous, while the literature recognizes that “connections” certainly help finding any job at all, it remains unclear if there is a long-term benefit. While it is difficult to record a network structure in most industries, in the adult film industry collaboration between performers is easily observed. Consequently, a collaborative network can be constructed for which centrality measures can be calculated in order to estimate the effect on success. Unfortunately, success is not easily observed either. Hence, in this manuscript, the survival in the industry is used as a proxy for professional success. This assumption is justified by the economic argument that, in the absence of lock-in effects, performers will remain in the industry as long as it remains profitable. The profitability will not only depend on monetary aspects, but, in addition to economic costs, it takes potential costs from loss of reputation and personal well-being into account. The research at hand stands stands out by pioneering the use of centrality measures in duration models which, to the best of my knowledge, is a novel approach in the field. The results indicate that there is a strong correlation between network centrality and industry survival for the adult film industry
Ion Dynamics in Concentrated Electrolyte Solutions:Relating Equilibrium Fluctuations of the Ions to TransportProperties in Battery Cells
No full textIn recent years, the interest in the development of highly concentratedelectrolyte solutions for battery applications has increased enormously. Suchelectrolyte solutions are typically characterized by a lowflammability, a highthermal and electrochemical stability and by the formation of a stable solidelectrolyte interphase (SEI) in contact to electrode materials. However, theclassification of concentrated electrolyte solutions in terms of the classicalscheme“strong”or“weak”has been controversially discussed in theliterature. In this paper, a comprehensive theoretical framework is presentedfor a more general classification, which is based on a comparison of chargetransport and mass transport. By combining the Onsager transportformalism with linear response theory, center-of-massfluctuations andcollective translational dipolefluctuations of the ions in equilibrium arerelated to transport properties in a lithium-ion battery cell, namely masstransport, charge transport and Li+transport under anion-blockingconditions. The relevance of the classification approach is substantiated byshowing that i) it is straightforward to classify highly concentratedelectrolytes and that ii)bothfast charge transport and fast mass transportare indispensable for achieving fast Li+transport under anion-blockingconditions.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Selected commensals educate the intestinal vascular and immune system for immunocompetence
No full textThe intestinal microbiota fundamentally guides the development of a normal intestinal physiology, the education, and functioning of the mucosal immune system. The Citrobacter rodentium-carrier model in germ-free (GF) mice is suitable to study the influence of selected microbes on an otherwise blunted immune response in the absence of intestinal commensals.
Here, we describe that colonization of adult carrier mice with 14 selected commensal microbes (OMM12 + MC2) was sufficient to reestablish the host immune response to enteric pathogens; this conversion was facilitated by maturation and activation of the intestinal blood vessel system and the step- and timewise stimulation of innate and adaptive immunity. While the immature colon of C. rodentium-infected GF mice did not allow sufficient extravasation of neutrophils into the gut lumen, colonization with OMM12 + MC2 commensals initiated the expansion and activation of the visceral vascular system enabling granulocyte transmigration into the gut lumen for effective pathogen elimination.
Consortium modeling revealed that the addition of two facultative anaerobes to the OMM12 community was essential to further progress the intestinal development. Moreover, this study demonstrates the therapeutic value of a defined consortium to promote intestinal maturation and immunity even in adult organisms.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Mikroskopische Modellierung des Exzitonentransports in verdrehten Van-der-Waals-Heterostrukturen
No full textThis thesis investigates exciton dynamics in twisted van der Waals structures, focusing on MoSe/WSe. It covers fundamental concepts, heterostructure analysis, and two case studies: exciton dynamics at different twist angles and the influence of polaron-induced exciton mass enhancementIn dieser Arbeit wird die Exzitonendynamik in verdrehten van der Waals-Strukturen untersucht, wobei der Schwerpunkt auf MoSe/WSe liegt. Sie umfasst grundlegende Konzepte, die Analyse von Heterostrukturen und zwei Fallstudien: Exzitonendynamik bei verschiedenen Verdrehungswinkeln und den Einfluss der polaroninduzierten Exzitonenmassenerhöhun
Same Place, Same Knowledge–Same People? The Geography of Non-Patent Citations in Dutch Polymer Patents
No full textIt has long been argued that geographic co-location supports knowledge spillovers. More recently, this argument has been challenged by showing that knowledge spillovers mainly flow through social networks, which may or may not be localized at various geographic scales. We further scrutinize the conjecture of geographically bounded knowledge spillovers by focusing on knowledge flows between academia and industry. Looking into citations to non-patent literature (NPL) in 2,385 Dutch polymer patents, we find that citation lags are shorter on average if Dutch rather than foreign NPLs are cited. However, when excluding individual and organizational self-citations, geographically proximate NPLs no longer diffuse faster than foreign NPLs. This suggests that knowledge is not “in the air” but transferred by mobile individuals and/or direct university-industry collaboration. Our findings moreover suggest an important role of international conferences in the diffusion of recent scientific knowledge
Incidence, outcome and relevance of urinary tract infections and ureteral stenosis in kidney transplant patients
No full textHarnwegsinfekte (HWIs) stellen ein relevantes klinisches Problem bei Patienten nach Nieren- (NTx) und kombinierter Nieren-Pankreas-Transplantation (NPTx) dar, da sie Transplantatfunktion und -überleben signifikant beeinflussen können. Während HWIs per se eine Abstoßung triggern können, begünstigen Ureterstenosen die Entwicklung von HWIs und vice versa; ebenso lässt die Immunsuppression post transplantationem betroffene Patienten für Infektionen empfänglicher werden.
Ziel der vorliegenden Untersuchung war es, die Inzidenz von Harnwegsinfektionen sowie von Harnleiterstenosen und deren Rolle auf die Nierenfunktion zu untersuchen. Dazu wurden retrospektiv verfügbare Daten aller erwachsenen Patienten mit terminaler Niereninsuffizienz analysiert, welche von Januar 2012 bis Juli 2020 im Transplantationszentrum Marburg eine Nieren- oder kombinierte Nieren- Pankreas-Transplantation erhalten hatten und mindestens 3 Monate nachbeobachtet worden waren. Erhoben wurden Inzidenz und Prävalenz von Harnwegsinfekten, Harnleiterstenosen und Rejektionen sowie epidemiologische Daten, kalte und warme Ischämiezeiten, immunologische Parameter und Komorbiditäten. Die
statistische Analyse erfolgte mit SPSS unter Anwendung des Chi-Quadrat-Tests oder dem exakten Test nach Fisher, binär logistischer Regression und der Bonferoni-Methode; p-Werte <.05 wurden als signifikant angesehen.
Insgesamt wurden 152 Patienten im Alter von 19-75 Jahren eingeschlossen (mittleres Alter 51,8 Jahre; 59,2% männlich; 132 NTx; 20 NPTx). HWIs traten am häufigsten innerhalb der ersten 3 Monate nach Transplantation (4,1 ± 2,3 Ereignisse; range 0-10) auf. Fast 50% der Patienten erfuhren mehr als 10 HWIs innerhalb von 24 Monaten post transplantationem, häufig mit multiplen Keimen. Häufigste Erreger waren Enterokokken oder Staphylokokken (74,3%), gefolgt von undifferenzierten gram-negativen Keimen (63,2%) and E. coli (69,1%). In fast der Hälfte aller Patienten (48,7%) konnte Enterococcus faecium nachgewiesen werden. Zu einem Transplantatverlust kam es bei 15 Patienten (9,9%) innerhalb des Bobachtungszeitraumes, wohingegen 129 Patienten eine weiterhin funktionierende Niere nach
bis zu 8 Jahren Nachbeobachtung hatten. Patienten mit Transplantatverlust hatten signifikant häufiger Harnwegsinfekte innerhalb der ersten 2 Jahre nach Transplantation als Patienten ohne Organverlust (p=0,009). Obgleich die Inzidenz von HWIs in beiden Gruppen initial vergleichbar war, nahm die Zahl der Infekte bei den Patienten ohne Transplantatverlust im Verlauf deutlich ab. Infektionen mit Staph. hämolyticus und Candida spp. waren mit einem erhöhten Risiko für ein Transplantatversagen verbunden. Eine Harnleiterstenose entwickelte sich bei 27 Patienten (18%) und war mit einer erhöhten Anzahl von HWIs (p<0,05), insbesondere bei einem Infekt mit Staph. epidermidis sowie E. faecalis, assoziiert. Histologisch gesicherte Rejektionen kamen bei 62 Patienten vor (40,8%) und zeigten einen
potentiellen Zusammenhang mit der renalen Grunderkrankung; darüber hinaus konnte eine vermehrte Anzahl von Abstoßungen ab einer kalten Ischämiezeit von 16 Stunden (p=0,028) beobachtet werden, während die warme Ischämiezeit offenbar keinen Einfluss hatte.
Zusammenfassend konnte gezeigt werden, dass:
(1) HWIs innerhalb der ersten 3 Monate nach Nierentransplantation häufig sind; (2) die Anzahl an HWIs sowie spezifische Keime mit einem erhöhten Risiko für einen Transplantatverlust assoziiert sind; (3) die Entwicklung von Ureterstenosen möglicherweise mit durch vorangegangene HWIs bedingt ist;
und (4) das Risko für Rejektionen v.a. mit einer verlängerten kalten Ischämiezeit zusammenhängt. Eine zielgerichtete antibiotische Therapie sowie die Minimierung der Kalten Ischämiezeit sind elementare Ansatzpunkte, um das renale Outcome nach NTX und NPTx zu verbessernUrinary tract infections (UTIs) pose a relevant problem in patients after kidney
transplantation and have a possible impact on graft function and graft survival. While UTIs may trigger a graft rejection, renal obstructions can also play a role in fostering UTIs in this cohort. The objective of this study was to assess incidence of UTIs and the role of the specific infections as well as the impact of ureter stenosis on kidney transplant outcome at the Marburg Transplant Center.
We retrospectively evaluated data from adult patients who had received a kidney (NTx) or combined kidney-pancreas transplant (NPTx) from January 2012 until July 2020 with a follow-up of at least 3 months. Incidence of UTIs and the pathogens as well as prevalence of ureter stenosis were noted. Epidemiologic data, cold and warm ischemia time, immunological parameters and comorbidities were extracted from patient charts and the electronic data system; and a potential association with UTIs was evaluated. Data was analyzed using chi-square test, exact Fisher’s test or the Bonferroni method; a p-value <.05 was considered significant.
A total of 152 transplant recipients (average age 51.8 years, range 19-75; male 59.2%, 132 NTx, 20 NPTx) were included. UTIs were most common within the first 3 months after transplantation (4.1±2.3 times; range 0-10). Almost 50% of the patients had more than 10 UTIs within 24 months after NTx or NPTx, often with multiple pathogens. Most common bacteria were enterococcus or staphylococcus species (74.3%) followed by undifferentiated gram-negative rods (63.2%) and E. coli (69.1%). In almost half of the patients (48.7%) enterococcus faecium was shown to be present. Graft loss was observed in 15 patients (9.9%), while 129 individuals still had a functioning transplant kidney at a follow-up of up to 8 years; no data was available in the remaining patients. Of note, patients with graft loss had significant more UTIs within the first 24 months compared to the cohort without graft loss (p=.009). Although the incidence of UTIs was comparable in both groups in the beginning, this number declined over time in patients without graft loss, whereas it remained high in those with deteriorating renal function. UTIs due
to staphylococcus epidermidis and candida species were associated with an
increased risk for transplant failure. A ureter stenosis developed in 27 patients (18%), associated with an increasing number of UTIs (p<.05), especially when staphylococcus epidermidis or enterococcus faecalis were present. Histo logically proven graft rejections occured in 62 patients (40,8%), demonstrating a potential association with the underlying renal disease. Morevover, a cold ischemia time (CIT) ≥ 16 hours resulted in significantly more rejection episodes (p=.028), while duration of warm ischemia time apparently did not have an impact on renal outcome.
In conclusion, we showed that: (1) UTIs are common in the first 3 months after kidney transplantation; (2) the number of UTIs as well as specific germs are associated with an increased risk for renal graft loss; (3) development of a n ureter stenosis may be related to prior UTIs; and (4) the risk for graft rejection is significantly associated with a long CIT. Targeted antibiotic therapy and reduction of CIT are essential means to improve renal graft outcome
Surgical Treatment of Calcified Thoracic Herniated Disc Disease via the Transthoracic Approach with the Use of Intraoperative Computed Tomography (iCT) and Microscope-Based Augmented Reality (AR)
No full textBackground and Objectives: The aim of this study is to present our experience in the surgical
treatment of calcified thoracic herniated disc disease via a transthoracic approach in the lateral
position with the use of intraoperative computed tomography (iCT) and augmented reality (AR).
Materials and Methods: All patients who underwent surgery for calcified thoracic herniated disc via a
transthoracic transpleural approach at our Department using iCT and microscope-based AR were
included in the study. Results: Six consecutive patients (five female, median age 53.2 ± 6.4 years) with
calcified herniated thoracic discs (two patients Th 10–11 level, two patients Th 7–8, one patient Th
9–10, one patient Th 11–12) were included in this case series. Indication for surgery included evidence
of a calcified thoracic disc on magnet resonance imaging (MRI) and CT with spinal canal stenosis of
>50% of diameter, intractable pain, and neurological deficits, as well as MRI-signs of myelopathy. Five
patients had paraparesis and ataxia, and one patient had no deficit. All surgeries were performed in
the lateral position via a transthoracic transpleural approach (Five from left side). CT for automatic
registration was performed following the placement of the reference array, with a high registration
accuracy. Microscope-based AR was used, with segmented structures of interest such as vertebral
bodies, disc space, herniated disc, and dural sac. Mean operative time was 277.5 ± 156 min. The use
of AR improved orientation in the operative field for identification, and tailored the resection of the
herniated disc and the identification of the course of dural sac. A control-iCT scan confirmed the
complete resection in five patients and incomplete resection of the herniated disc in one patient. In
one patient, complications occurred, such as postoperative hematoma, and wound healing deficit
occurred. Mean follow-up was 22.9 ± 16.5 months. Five patients improved following surgery, and one
patient who had no deficits remained unchanged. Conclusions: Optimal surgical therapy in patients
with calcified thoracic disc disease with compression of dural sac and myelopathy was resectioned via
a transthoracic transpleural approach. The use of iCT-based registration and microscope-based AR
significantly improved orientation in the operative field and facilitated safe resection of these lesions.Gefördert durch den Open-Access-Publikationsfonds der UB Marburg
Untersuchungen zur Epidemiologie von Klebsiella pneumoniae auf einer herzchirurgischen Intensivstation mittels Massenspektrometrie
No full textIn dieser Arbeit wurde die Frage untersucht, ob es möglich ist, mithilfe der MALDI-TOF Massenspektrometrie epidemiologische Zusammenhänge von Klebsiella pneumoniae Isolaten und deren Abstammungsbeziehungen erkennen zu können. Die analysierten Isolate (n = 56) entstammten der routinemäßigen Testung von intensivmedizinisch betreuten Patienten in einem Krankenhaus in Deutschland. Damit konzentrierte sich diese Untersuchung auf die alltägliche Epidemiologie dieser Bakterienspezies über einen Zeitraum von eineinhalb Jahren. Mittels MALDI-TOF, softwaregestützter Datenverarbeitung und Clusteranalyse konnten 12 MALDI Typen von K. pneumoniae differenziert werden. Die Betrachtung des zeitlichen Auftretens dieser Typen ließ vermuten, dass es sich hierbei um sehr begrenzte und zeitlich kurzfristige Übertragungsereignisse handelte, sog. „Mini-Cluster“. Weiterhin erfolgte eine vergleichende Analyse einer 36 Isolate umfassenden Stichprobe mit Typisierungsergebnissen einer Referenzmethode (Pulsfeldgelelektrophorese, PFGE). Mit einem Adjusted Rand Index (ARI) von 0,761 zeigte sich eine gute Übereinstimmung der beiden Typisierungsmethoden.In this thesis, the question of whether it is possible to detect epidemiological relationships of K. pneumoniae isolates using MALDI-TOF mass spectrometry was investigated. All of the 56 analyzed Klebsiella pneumoniae isolates came from routine testing of patients receiving intensive care at a hospital in Germany. The study focused on the day-to-day epidemiology of this bacterial species over a period of 18 months. Using MALDI-TOF, software-assisted data processing and cluster analysis, 12 MALDI types of K. pneumoniae could be differentiated. Consideration of the temporal occurrence suggested that many of the K. pneumoniae types can be seen as limited and temporally short-term transmission events, so-called "mini-clusters". Furthermore, a comparative analysis of a sample of 36 isolates with typing results of a reference method (pulsed field gel electrophoresis (PFGE)) was performed. With an Adjusted Rand Index (ARI) of 0.761, a good agreement between the two typing methods was found