Temporal fluctuations in excimer-like interactions between pi-conjugated chromophores

Inter- or intramolecular coupling processes between chromophores such as excimer formation or H- and J-aggregation are crucial to describing the photophysics of closely packed films of conjugated polymers. Such coupling is highly distance dependent, and should be sensitive to both fluctuations in the spacing between chromophores as well as the actual position on the chromophore where the exciton localizes. Single-molecule spectroscopy reveals these intrinsic fluctuations in well-defined bi-chromophoric model systems of cofacial oligomers. Signatures of interchromophoric interactions in the excited state - spectral red-shifting and broadening, and a slowing of photoluminescence decay - correlate with each other but scatter strongly between single molecules, implying an extraordinary distribution in coupling strengths. Furthermore, these excimer-like spectral fingerprints vary with time, revealing intrinsic dynamics in the coupling strength within one single dimer molecule, which constitutes the starting point for describing a molecular solid. Such spectral sensitivity to sub-Angstrom molecular dynamics could prove complementary to conventional FRET-based molecular rulers

Simulating a patient's fall as a means to improve routine communication: Joint training for nursing and fifth-year medical students

Background: Physicians and nursing staff interact as a team on a daily basis in hospital settings. However, both educational paths offer few opportunities to establish contact with the other professional group. Neither professional group can practice its later role with the other group in a “safe” learning environment. Routine interprofessional collaboration is described as being in need of great improvement and carries with it the potential for conflict. To improve interprofessional communication and task management, a simulation-based emergency training session for nursing students and fifth-year medical students was developed at the KRH Klinikum Nordstadt in Hanover, Germany. As a pilot project, the course was held twice in the form of a one-day session with ten nursing and four medical students.Project: Using the example of a patient’s fall, course participants were able to observe and actively treat multiple simulated patients. Following each simulation the trainer conducted a comprehensive debriefing. The course was then evaluated using a questionnaire.Results: The evaluation of the team training showed a high level of acceptance among the two participating professional groups. On a scale of 1 (hardly applicable) to 5 (strongly applicable), the course was given a 4 by both professional groups for its relevance to daily work. In the open-ended written responses praise was specifically given for the opportunity to learn how to switch perspectives as a result of the simulation exercises.Conclusion: A common emergency on the hospital ward offers a good opportunity to establish and practice interprofessional team skills. With the knowledge gained about communication and the ability to change viewpoints, participants are able to improve their team skills. Participants demonstrated a high degree of acceptance for the training program

Przezcewnikowe zamknięcie drożnego otworu owalnego w prewencji wtórnej choroby dekompresyjnej u zawodowych nurków — doświadczenie jednoośrodkowe w obserwacji odległej

Background: Patent foramen ovale (PFO) with occasional right-to-left shunting is associated with an increased risk of de¬compression illness (DCI). Divers with a history of repetitive or severe DCI and diagnosed with PFO should be considered for transcatheter closure if they wish to continue with unrestricted diving. Aim: To summarise our centre’s experience in transcatheter PFO closure in professional divers with a history of DCI. Methods: A follow-up of 11 consecutive divers (nine males, two females) in whom device PFO closure was performed be¬tween 2001 and 2015 was carried out by phone contact. Available medical records and diving logbooks were reviewed to determine individual DCI symptomatology, indications to the procedure, and to evaluate modifications in the diving practice. Results: Each patient experienced at least one event of DCI before the procedure, and eight patients experienced more than one event. Total number of reported events was 62. The vast majority of events (97%) followed dives consistent with safe decompression policies. The median follow-up was 91 (minimum nine, maximum 172) months. No complications of the intervention were observed. All patients returned to unrestricted, deep diving, performing a total of 3610 dives with the median number of 225 dives (lower quartile value: 82.5 dives, upper quartile value: 725 dives). The majority of subjects dived as deep as they did before the intervention, or deeper, achieving mean maximum depth of 93.8 ± 35.6 m (vs. 89.7 ± 25.9 m before the intervention, p = 0.71). No episodes of DCI were reported during the follow-up period. Conclusions: Transcatheter closure of PFO appears to be reasonably effective in secondary prevention of DCI associated with intra-cardiac shunting.Wstęp: Drożny otwór owalny (PFO) z obecnością przecieku prawo-lewego zwiększa ryzyko wystąpienia choroby dekompresyjnej (DCI). Osoby z wywiadem nawracających lub ciężkich epizodów DCI oraz rozpoznanym PFO, chcące kontynuować nurkowanie w nieograniczonym zakresie, są potencjalnymi kandydatami do przezcewnikowego zamknięcia otworu. Cel: Celem niniejszej pracy było podsumowanie dotychczasowych doświadczeń ośrodka, w którym pracują autorzy, w zabiegach przezcewnikowego zamknięcia PFO w prewencji wtórnej DCI u zawodowych nurków. Metody: W latach 2001–2015 zabiegom przezcewnikowego zamknięcia PFO poddano 11 zawodowych nurków (9 mężczyzn, 2 kobiety) z wywiadem DCI. Szczegółowe dane dotyczące objawów DCI, kwalifikacji do zabiegu i krótkoterminowych wyników leczenia uzyskano na podstawie dostępnej dokumentacji medycznej. Wyniki obserwacji odległej oparto na danych uzyskanych dzięki kontaktowi telefonicznemu. Z wszystkimi pacjentami skontaktowano się w listopadzie 2015 r. Wyniki: Każdy chory doznał przynajmniej jednego epizodu DCI przed zabiegiem, przy czym 8 (73%) pacjentów doznało więcej niż jednego epizodu. Całkowita liczba zgłoszonych epizodów wyniosła 62, z czego większość (97%) była poprzedzona nurkowaniem zgodnym z zasadami bezpiecznej dekompresji. Mediana czasu obserwacji wyniosła 91 miesięcy (minimalnie 9 miesięcy, maksymalnie 172 miesiące). Nie obserwowano wczesnych ani odległych powikłań zabiegu. Wszyscy pacjenci powrócili do nieograniczonego nurkowania, wykonując łącznie 3610 nurkowań (mediana 225; rozkład kwartylowy: K1 = 82,5; K3 = 725). Większość (64%) pacjentów schodziła na głębokości nie mniejsze niż przed procedurą; średnia maksymalna głębokość nurkowań wyniosła 93,8 +/- 35,6 m (vs. 89,7 +/- 25,9 m przed procedurą; p = 0,71). U żadnego z pacjentów nie obserwowano nawrotu DCI. Wnioski: Przezcewnikowe zamknięcie PFO wydaje się zasadną metodą zapobiegania nawrotom DCI u nurków ze zdiagnozowanym przeciekiem prawo-lewym

Pulmonary artery rupture as a complication of Swan-Ganz catheter application. Diagnosis and endovascular treatment: a single centre’s experience

Introduction: The placement of a Swan-Ganz catheter into the pulmonary artery may lead to a number of complications (2–17%). In less than 0.2% of cases Swan-Ganz catheterization results in serious vascular damage – pulmonary artery rupture (PAR). This paper presents two distinct forms of iatrogenic PAR treated endovascularly using different vascular devices. Aim: To evaluate the effectiveness of endovascular treatment and the application of different types of vascular devices in the management of pulmonary artery rupture caused by Swan-Ganz catheterization. Material and methods : In this retrospective study we evaluated 2 patients in whom Swan-Ganz catheter application was used for perioperative monitoring and resulted in pulmonary artery rupture. This complication was treated endovascularly by means of interventional cardiology. Results : We report the cases of 2 patients with a pulmonary artery pseudoaneurysm formed in the perioperative period. In case 1, a single, 4-loop, 3 mm diameter coil was implanted. In case 2, a 5 mm Amplatzer Vascular Plug IV was applied. In both cases, the endovascular approach resulted in total occlusion of the feeding artery and reduced further extravasation of the blood. Conclusions : Despite its extremely low incidence, iatrogenic PAR is a serious, life-threatening complication of Swan-Ganz catheterization that requires urgent attention. Among available methods of treatment, percutaneous embolization is a relatively quick, safe, accurate and highly effective alternative to traumatizing surgery

Cardiovascular Magnetic Resonance in Peripartum Cardiomyopathy: Comparison with Idiopathic Dilated Cardiomyopathy

Background: Peripartum (PPCM) and dilated (DCM) cardiomyopathies are distinct forms of cardiac disease that share certain aspects in clinical presentation. Aim: We hypothesized that different cardiac structural changes underlie PPCM and DCM, and we aimed to investigate them with cardiovascular magnetic resonance (CMR). Methods: We included 21 PPCM patients (30.5 ± 5.9 years) and 30 female DCM patients (41.5 ± 16.8 years) matched for left ventricular ejection fraction. Biventricular and biatrial volumetric and functional parameters were assessed along with ventricular and atrial strain indices based on feature-tracking techniques. The presence of late gadolinium enhancement (LGE) was also assessed. Results: In PPCM, the left ventricular (LV) stroke volume index was lower (p = 0.04), right atrial (RA) minimal and pre-systolic volumes were higher (p < 0.01 and p = 0.02, respectively), and the total RA ejection fraction was lower (p = 0.02) in comparison to DCM. Moreover, in PPCM, the LV global longitudinal strain (p = 0.03), global circumferential strain rate (p = 0.04), and global longitudinal strain rate (p < 0.01) were less impaired than in DCM. Both PPCM and DCM patients with LGE had more dilated ventricles and more impaired LV and left atrial function than in PPCM and DCM patients without LGE. Conclusions: Subtle differences appear on CMR between PPCM and DCM. Most importantly, the RA is larger and more impaired, and LV global longitudinal strain is less reduced in PPCM than in DCM. Furthermore, similarly to DCM, PPCM patients with LGE have more dilated and impaired ventricles than patients without LGE

The Effect of Intensive Dietary Intervention on the Level of RANTES and CXCL4 Chemokines in Patients with Non-Obstructive Coronary Artery Disease: A Randomised Study

Background: Inflammation is the key pathophysiological mechanism of the initiation and progression of atherosclerosis. The study objective was to assess the effects of a dietary intervention based on the model of the dietary approaches to stop hypertension (DASH) diet on the levels of chemokines RANTES and CXCL4 in patients with non-obstructive coronary artery disease. Methods: As part of Dietary Intervention to Stop Coronary Atherosclerosis in Computed Tomography (DISCO-CT) study, patients were randomised to an intervention group (n = 40), where the DASH diet was introduced along with optimal pharmacotherapy, and to a control group (n = 39), with optimal pharmacotherapy alone. In the DASH group, systematic dietary counselling was provided for the follow-up period. RANTES and CXCL4 levels were determined using ELISA. Results: In the DASH group, the RANTES level insignificantly reduced from 42.70 ± 21.1 ng/mL to 38.09 ± 18.5 ng/mL (p = 0.134), and the CXCL4 concentration significantly reduced from 12.38 ± 4.1 ng/mL to 8.36 ± 2.3 ng/mL (p = 0.0001). At the same time, an increase in the level of both chemokines was observed in the control group: RANTES from 34.69 ± 22.7 to 40.94 ± 20.0 ng/mL (p = 0.06) and CXCL4 from 10.98 ± 3.6 to 13.0 5± 4.8 ng/mL (p = 0.009). The difference between the changes in both groups was significant for both RANTES (p = 0.03) and CXCL4 (p = 0.00001). The RANTES/CXCL4 ratio reduced in the control group (from 3.52 ± 2.8 to 3.35 ± 2.8; p = 0.006), while in the DASH group, an increase was observed (from 3.54 ± 1.7 to 4.77 ± 2.4; p = 0.001). Conclusions: A 12-month-long intensive dietary intervention based on DASH diet guidelines as an addition to optimal pharmacotherapy causes changes in the levels of chemokines CXCL4 and RANTES and their mutual relationship in comparison to conventional treatment

Usefulness of MCP-1 Chemokine in the Monitoring of Patients with Coronary Artery Disease Subjected to Intensive Dietary Intervention: A Pilot Study

Monocyte chemotactic protein-1 (MCP-1) plays an important role in the entire atherosclerotic process, from atherogenesis to destabilisation of the atherosclerotic plaque. The purpose of this study is to evaluate the effect of the dietary approaches to stop hypertension (DASH) diet in patients with coronary artery disease on the MCP-1 plasma concentration and to evaluate the potential usefulness of this chemokine as a marker of change in the volume and composition of coronary plaque. Material and method. As part of the dietary intervention to stop coronary atherosclerosis in computed tomography (DISCO-CT) study, patients were randomised to an intervention group (n = 40) in which the DASH diet was introduced, and to a control group (n = 39) with no dietary intervention. In the DASH group, dietary counselling was provided at all follow-up visits within 12 months of the follow-up period. MCP-1 plasma concentration was determined using enzyme-linked immunosorbent assay (ELISA). Coronary plaque analysis was performed using a semi-automated plaque analysis software system (QAngioCT, Medis, The Netherlands). Results. In the DASH group, MCP-1 plasma concentration significantly decreased by 34.1 pg/mL (p = 0.01), while in the control group, the change in MPC-1 was not significant. Significant inverse correlations were revealed for the change in MCP-1 plasma concentration and change in the consumption of vitamin C and dietary fibre both in the DASH (r = −0.519, p = 0.0005; r = −0.353, p = 0.025, respectively) and in the control group (r = −0.488 p = 0.001; r = −0.502, p = 0.001, respectively). In patients with the highest decrease in percent atheroma volume (PAV), a significant positive correlation was observed between the change in MCP-1 plasma concentration and changes in PAV (r = 0.428, p = 0.033) and calcified plaque component (r = 0.468, p = 0.018), while the change in noncalcified plaque component correlated inversely with change in MCP1 (r = −0.459, p = 0.021). Conclusion. Dietary intervention based on the DASH diet model reduces the MCP-1plasma concentration, mostly due to an increased intake of plant-derived, fibre-rich foods and antioxidants. The change in MCP-1 plasma concentration seems to reflect changes in the atheroma volume and proportions between the calcified and non-calcified plaque elements