Utilization of remote reprogramming to manage insertable cardiac monitor arrhythmia alert burden

INTRODUCTION

The increasing use of insertable cardiac monitors (ICMs) for long-term continuous arrhythmia monitoring creates a high volume of transmissions and a significant workload for clinics. The ability to remotely reprogram device alert settings without in-office patient visits was recently introduced, but its impact on clinic workflow compared to the previous ICM iteration is unknown.

METHODS

The aim of this real-world study was to evaluate the impact of device reprogramming capabilities on ICM alert burden and on clinic workflow. Deidentified data was obtained from US patients and a total of 19 525 receiving a LINQ II were propensity score-matched with 19 525 implanted with LINQ TruRhythm (TR) ICM based on age and reason for monitoring.

RESULTS

After reprogramming, ICM alerts reduced by 20.5% (p < .001). Compared with patients monitored with LINQ TR, patients with LINQ II had their device reprogrammed sooner after implant and more frequently during follow-up. Adoption of remote programming was projected to lead to an annual total clinic time savings of 211 h per 100 ICM patients managed.

CONCLUSION

These data suggest that utilization of ICM alert reprogramming has increased with remote capabilities, which may reduce clinic and patient burden for ICM follow-up and free clinician time for other valuable patient care activities.

Heart Rhythm Society Atrial Fibrillation Centers of Excellence Study: A survey analysis of stakeholder practices, needs, and barriers

BACKGROUND

An integrated, coordinated, and patient-centered approach to atrial fibrillation (AF) care delivery may improve outcomes and reduce cost.

OBJECTIVE

The purpose of this study was to gain a better understanding from key stakeholder groups on current practices, needs, and potential barriers to implementing optimal integrated AF care.

METHODS

A series of comprehensive questionnaires were designed by the Heart Rhythm Society Atrial Fibrillation Centers of Excellence (CoE) Task Force to conduct surveys with physicians, advanced practice professionals, patients, and hospital administrators. Data collected focused on the following areas: access to care, stroke prevention, education, AF quality improvement, and AF CoE needs and barriers. Survey responses were collated and analyzed by the Task Force.

RESULTS

The surveys identified 5 major unmet needs: (1) Standardized protocols, order sets, or care pathways in the emergency department or inpatient setting were uncommon (36%-42%). (2) All stakeholders agreed stroke prevention was a top priority; however, prior bleeding or risk of bleeding was the most frequent barrier for initiation. (3) Patients indicated that education on modifiable causes, AF-related complications, and lowering stroke risk is most important. (4) Less than half (43%) of the health care systems track patients with AF or treatment status. Patients reported that stroke and heart failure prevention and access to procedures were priority areas for an AF CoE. The most common barriers to implementing AF CoE identified by clinicians were administrative support (69%) and cost (52%); administrators reported physical space (43%).

CONCLUSION

On the basis of the findings of this study, the Task Force identified high priority areas to develop initiatives to aid the implementation of AF CoE.

Virtual Reality Therapy in Palliative Care: A Case Series

OBJECTIVES

Virtual reality (VR) opens a variety of therapeutic options to improve symptom burden in patients with advanced disease. Until to date, only few studies have evaluated the use of VR therapy in the context of palliative care. This case series aims to evaluate the feasibility and acceptability of VR therapy in a population of palliative care patients.

METHODS

In this single-site case series, we report on six palliative care patients undergoing VR therapy. The VR therapy consisted of a one-time session ranging between 20 to 60 minutes depending on the patient's needs and the content chosen for the VR sessions. A semi-structured survey was conducted and the Edmonton Symptom Assessment System (ESAS) and the Distress Thermometer were performed pre- and post-intervention.

RESULTS

Overall, VR therapy was well accepted by all patients. Five out of six patients reported having appreciated VR therapy. There were individual differences of perceived effects using VR therapy. The semi-structured survey revealed that some patients felt a temporary detachment from their body and that patients were able to experience the VR session as a break from omnipresent worries and the hospital environment ("I completely forgot where I am"). There was a considerable reduction in the total ESAS score post-treatment (T0 ESASTot = 27.2; T1 ESASTot = 18.8) and a slightly reduction in distress (T0 DTTot = 4.4; T1 DTTot = 3.8). However, two patients were more tired after the intervention.Significance of Results: Our preliminary results demonstrate that VR therapy is acceptable, feasible and safe for use within a palliative care population and appears to be a viable treatment option. Clinical trials are both warranted and necessary to confirm any therapeutic effects of VR therapy, as is the need to tailor VR systems better for use in palliative care settings.

Challenges in managing a remote monitoring device clinic

Background

Recent advances in remote cardiac monitoring technology have created new challenges for clinicians and staff working in device clinics who are left processing large volumes of data. Often, this process is fractured and inefficient, with occurrence of unnecessary alerts that strain staff time and resources.

Objective

The purpose of this survey was to identify challenges allied health professional clinicians and staff encounter when managing a remote monitoring device clinic.

Methods

A 27-item mixed methods survey was developed using a Qualtrics-encrypted, anonymous Web survey tool. Demographic information and questions rating satisfaction level for remote device clinic issues were obtained using a 5-point Likert scale. Three open-ended questions were included that addressed challenges and successes in managing a remote monitoring clinic and served as a method for identifying common themes.

Results

Major themes identified were poor connectivity, staffing issues, and large volume of alerts. Approximately 50% of respondents were either satisfied or unsatisfied with issues surrounding managing remote monitoring device clinics. Strategies for success included optimizing alerts, assigning designated staff, and partnering with third-party platforms.

Conclusion

This survey confirms these issues as an opportunity for industry and digital health leaders to determine best practices for incorporating these technologies into patient care.

Clinic Time Required for Remote and In-person Management of Cardiac Device Patients: Time and Motion Workflow Evaluation

BACKGROUND

The number of patients with cardiac implantable electronic devices (CIEDs) is growing, creating substantial workload for device clinics.

OBJECTIVE

This study aimed to characterize the workflow and quantify clinic staff time requirements to manage CIED patients.

METHODS

A time and motion workflow evaluation was performed in 11 US and European CIED clinics. Workflow tasks were repeatedly timed during one business week of observation at each clinic. Observations were inclusive of all device models/manufacturers present. Mean cumulative staff time required to review a Remote device transmission and for an In-person clinic visit were calculated, including all necessary clinical and administrative tasks. Annual staff time for follow-up of 1 CIED patient was modeled using CIED transmission volumes, clinical guidelines, and published literature.

RESULTS

A total of 276 in-person clinic visits and 2,173 remote monitoring activities were observed. Mean staff time required per remote transmission ranged from 9.4-13.5 minutes for therapeutic devices (pacemaker, ICD, CRT) and 11.3-12.9 mins for diagnostic devices (insertable cardiac monitors (ICMs)). Mean staff time per in-person visit ranged from 37.8-51.0 mins and 39.9-45.8 mins, for therapeutic devices and ICMs respectively. Including all remote and in-person follow-ups, the estimated annual time to manage one CIED patient ranged from 1.6-2.4 hours for therapeutic devices and 7.7-9.3 hours for ICMs.

CONCLUSIONS

CIED patient management workflow is complex and requires significant staff time. Understanding process steps and time requirements informs implementation of efficiency improvements, including remote solutions. Future research should examine the heterogeneity in patient management processes to identify the most efficient workflows.

CLINICALTRIAL

Patterns of integrating palliative care into standard oncology in an early ESMO designated center: a 10-year experience

BACKGROUND

Integration of specialist palliative care (PC) into standard oncology care is recommended. This study investigated how integration at the Cantonal Hospital St. Gallen (KSSG) was manifested 10 years after initial accreditation as a European Society for Medical Oncology (ESMO) Designated Center (ESMO-DC) of Integrated Oncology and Palliative Care.

METHODS

A chart review covering the years 2006-2009 and 2016 was carried out in patients with an incurable malignancy receiving PC. Visual graphic analysis was utilized to identify patterns of integration of PC into oncology based on the number and nature of medical consultations recorded for both specialties. A follow-up cohort collected 10 years later was analyzed and changes in patterns of integrating specialist PC into oncology were compared.

RESULTS

Three hundred and forty-five patients from 2006 to 2009 and 64 patients from 2016 were included into analyses. Four distinct patterns were identified using visual graphic analysis. The 'specialist PC-led pattern' (44.9%) and the 'oncology-led pattern' (20.3%) represent disciplines that took primary responsibility for managing patients, with occasional and limited involvement from other disciplines. Patients in the 'concurrent integrated care pattern' (18.3%) had medical consultations that frequently bounced between specialist PC and oncology. In the 'segmented integrated care pattern' (16.5%), patients had sequences of continuous consultations provided by one discipline before alternating to a stretch of consultations provided by the other specialty. In the 2016 follow-up, while the 'oncology-led pattern' occurred significantly less frequently relative to the 'specialist PC-led pattern' and the 'segmented integrated care pattern', the 'concurrent integrated care pattern' emerged more frequently when compared with the 2006-2009 follow-up.

CONCLUSION

The 'specialist PC-led pattern' was the most prominent pattern in this data. The 2016 follow-up showed that a growing number of patients received a collaborative pattern of care, indicating that integration of specialist PC into standard oncology can manifest as either segmented or concurrent care pathways. Our data suggest a closer, more dynamic and flexible collaboration between oncology and specialist PC early in the disease course of patients with advanced cancer and concurrent with active treatment.

SAS CARE 2 - a randomized study of CPAP in patients with obstructive sleep disordered breathing following ischemic stroke or transient ischemic attack

Objective/background

The benefit of Continuous Positive Airway Pressure (CPAP) treatment following ischemic stroke in patients with obstructive sleep-disordered breathing (SDB) is unclear. We set out to investigate this open question in a randomized controlled trial as part of the SAS-CARE study.

Patients/methods.

Non-sleepy patients (ESS < 10) with ischemic stroke or transient ischemic attack (TIA) and obstructive SDB (AHI ≥ 20) 3 months post-stroke were randomized 1:1 to CPAP treatment (CPAP+) or standard care. Primary outcome was the occurrence of vascular events (TIA/stroke, myocardial infarction/revascularization, hospitalization for heart failure or unstable angina) or death within 24 months post-stroke. Secondary outcomes included Modified Rankin Scale (mRS) and Barthel Index.

Results

Among 238 SAS-CARE patients 41 (17%) non-sleepy obstructive SDB patients were randomized to CPAP (n = 19) or standard care (n = 22). Most patients (80%) had stroke and were males (78%), mean age was 64 ± 7 years and mean NIHSS score 0.6 ± 1.0 (range: 0–5). The primary endpoint was met by one patient in the standard care arm (a new stroke). In an intent-to treat analysis disregarding adherence, this corresponds to an absolute risk difference of 4.5% or an NNT = 22. mRS and Barthel Index were stable and similar between arms. CPAP adherence was sufficient in 60% of evaluable patients at month 24.

Conclusion

No benefit of CPAP started three months post-stroke was found in terms of new cardio- and cerebrovascular events over 2 years. This may be related to the small size of this study, the mild stoke severity, the exclusion of sleepy patients, the delayed start of treatment, and the overall low event rate.

•

No benefit of CPAP started 3 months post-stroke was found.

•

A sufficient CPAP compliance was observed over 2 years in 60% of patients.

•

Studies of CPAP in mild stroke need to be large and include long-term outcomes.

Predictors of atrial fibrillation detection and features of recurrent strokes in patients after cryptogenic stroke

BACKGROUND AND PURPOSE

Use of implantable cardiac monitors (ICMs) has increased diagnosis of atrial fibrillation (AF) in cryptogenic stroke (CS) patients. Identifying AF predictors may enhance the yield of AF detection. Recurrent strokes after CS are not well described. We aimed to assess the predictors for AF detection and the characteristics of recurrent strokes in patients after CS.

METHODS

We reviewed electronic medical records of CS patients who were admitted between February 2014 and September 2017 and underwent ICM placement with minimum one-year follow-up. Patient demographics, stroke characteristics, pre-defined risk factors as well as recurrent strokes were compared between patients with and without AF detection.

RESULTS

389 patients with median follow-up of 548 days were studied. AF was detected in 102 patients (26.2%). Age (per decade increase, OR 2.10, CI 1.64-2.68, with vs. without AF) and left atrium diameter (per 5 mm increase, OR 1.91, CI 1.33-2.74) were identified as AF predictors. Intracranial large vessel stenosis >50% irrelevant to the index strokes was associated with AF detection within 30 days (OR 0.24, CI 0.09-0.69, >30 vs. <30 days). Recurrent strokes occurred in 14% patients with median follow-up about 2.5 years. Topography of these strokes resembled embolic pattern and was comparable between patients with and without AF. Among recurrent strokes in patients with AF, the median time to AF detection was much shorter (90 vs. 251 days), and the median time to first stroke recurrence was much longer (422 vs. 76 days) in patients whose strokes recurred after AF detection than those before AF detection.

CONCLUSIONS

Older age and enlarged left atrium are predictors for AF detection in CS patients. Intracranial atherosclerosis is more prevalent in patients with early AF detection within 30 days. Recurrent strokes follow the embolic pattern, and early AF detection could delay the stroke recurrence.

Guidance for Rebooting Electrophysiology Through the COVID-19 Pandemic From the Heart Rhythm Society and the American Heart Association Electrocardiography and Arrhythmias Committee of the Council on Clinical Cardiology: Endorsed by the American College of Cardiology

Coronavirus disease 2019 (COVID-19) has presented substantial challenges to patient care and impacted health care delivery, including cardiac electrophysiology practice throughout the globe. Based upon the undetermined course and regional variability of the pandemic, there is uncertainty as to how and when to resume and deliver electrophysiology services for arrhythmia patients. This joint document from representatives of the Heart Rhythm Society, American Heart Association, and American College of Cardiology seeks to provide guidance for clinicians and institutions reestablishing safe electrophysiological care. To achieve this aim, we address regional and local COVID-19 disease status, the role of viral screening and serologic testing, return-to-work considerations for exposed or infected health care workers, risk stratification and management strategies based on COVID-19 disease burden, institutional preparedness for resumption of elective procedures, patient preparation and communication, prioritization of procedures, and development of outpatient and periprocedural care pathways.

Guidance for Rebooting Electrophysiology Through the COVID-19 Pandemic From the Heart Rhythm Society and the American Heart Association Electrocardiography and Arrhythmias Committee of the Council on Clinical Cardiology

Coronavirus disease 2019 (COVID-19) has presented substantial challenges to patient care and impacted healthcare delivery, including cardiac electrophysiology practice throughout the globe. Based upon the undetermined course and regional variability of the pandemic, there is uncertainty as to how and when to resume and deliver electrophysiology services for patients with arrhythmia. This joint document from representatives of the Heart Rhythm Society, American Heart Association, and American College of Cardiology seeks to provide guidance for clinicians and institutions reestablishing safe electrophysiological care. To achieve this aim, we address regional and local COVID-19 disease status, the role of viral screening and serological testing, return-to-work considerations for exposed or infected health care workers, risk stratification and management strategies based on COVID-19 disease burden, institutional preparedness for resumption of elective procedures, patient preparation and communication, prioritization of procedures, and development of outpatient and periprocedural care pathways.

Guidance for rebooting electrophysiology through the COVID-19 pandemic from the Heart Rhythm Society and the American Heart Association Electrocardiography and Arrhythmias Committee of the Council on Clinical Cardiology: Endorsed by the American College of Cardiology

Coronavirus disease 2019 (COVID-19) has presented substantial challenges to patient care and impacted health care delivery, including cardiac electrophysiology practice throughout the globe. Based upon the undetermined course and regional variability of the pandemic, there is uncertainty as to how and when to resume and deliver electrophysiology services for arrhythmia patients. This joint document from representatives of the Heart Rhythm Society, American Heart Association, and American College of Cardiology seeks to provide guidance for clinicians and institutions reestablishing safe electrophysiological care. To achieve this aim, we address regional and local COVID-19 disease status, the role of viral screening and serologic testing, return-to-work considerations for exposed or infected health care workers, risk stratification and management strategies based on COVID-19 disease burden, institutional preparedness for resumption of elective procedures, patient preparation and communication, prioritization of procedures, and development of outpatient and periprocedural care pathways.

P577Early experience with the first pacemakers to directly connect with smart devices for remote monitoring

Background

Remote monitoring is associated with improved patient outcomes; however, adoption and adherence to remote monitoring via home-based consoles remains suboptimal. BlueSync technology in new generation pacemaker and CRT-P models enables the implanted device to communicate directly with patient-owned, Bluetooth-equipped smartphones/tablets and an app (MyCareLink Heart). The app can automatically retrieve information from the cardiac device and transmit the data to the remote network, eliminating the need for traditional remote monitoring consoles.

Objectives

To characterize the communication process between implanted pacemakers and smart device remote monitoring apps by assessing the success of prescheduled remote transmissions in the first month of follow-up. Additionally, to assess the feedback of both patients and clinicians about the process of device pairing.

Methods

Enrollment in the BlueSync Field Evaluation began in April 2018 and was completed November 2018. Follow-up is ongoing. Prior to enrollment in the evaluation, patients completed the device pairing process with the app using their own compatible smartphone or tablet. Patient and clinician questionnaires were completed at the time of the device pairing process. After enrollment, successful completion of scheduled transmissions occurring in the first month were analyzed.

Results

Preliminary data includes 241 enrolled patients with mean age of 64.7±15.5 yrs (min 20, max 90 yrs), who completed device pairing between their implanted device and their smart device app. Of enrolled patients, 79% felt that the device paring was easy to do, 85% were satisfied with the amount of time it took to complete it, and 93% felt that they would be comfortable using the app. Clinicians reported that 67% of the device pairings took less than 20 minutes and 78% felt patients would be able to use the app independently. At the time of analysis 174 patients had at least one scheduled transmission within the first month, and collectively had a total of 322 scheduled transmissions. Out of these, 309 (96%, 95% CI: 93%-98%) were successfully completed.

MyCareLink Heart App

Conclusions

Initial experience with the world's first app based remote monitoring system for Bluetooth enabled pacemakers demonstrated success to scheduled transmissions in the first month across a wide range of patient ages. Patients and clinicians reported high satisfaction with this novel technology.

Acknowledgement/Funding

Medtronic PLC

Extent of Microstructural Tissue Damage Correlates with Hemodynamic Failure in High-Grade Carotid Occlusive Disease: An MRI Study Using Quantitative T2 and DSC Perfusion

BACKGROUND AND PURPOSE

Chronic hemodynamic impairment in high-grade carotid occlusive disease is thought to cause microstructural abnormalities that might be subclinical or lead to subtle symptoms including cognitive impairment. Quantitative MR imaging allows assessing pathologic structural changes beyond macroscopically visible tissue damage. In this study, high-resolution quantitative T2 mapping combined with DSC-based PWI was used to investigate quantitative T2 changes as a potential marker of microstructural damage in relation to hemodynamic impairment in patients with unilateral high-grade carotid occlusive disease.

MATERIALS AND METHODS

Eighteen patients with unilateral high-grade ICA or MCA stenosis/occlusion were included in the study. T2 values and deconvolved perfusion parameters, including relative CBF, relative CBV, and the relative CBF/relative CBV ratio as a potential indicator of local cerebral perfusion pressure, were determined within areas with delayed TTP and compared with values from contralateral unaffected areas after segmentation of normal-appearing hypoperfused WM and cortical regions. Hemispheric asymmetry indices were calculated for all parameters.

RESULTS

Quantitative T2 was significantly prolonged (P < .01) in hypoperfused tissue and correlated significantly (P < .01) with TTP delay and relative CBF/relative CBV reduction in WM. Significant correlations (P < .001) between TTP delay and the relative CBF/relative CBV ratio were found both in WM and in cortical areas.

CONCLUSIONS

Quantitative T2 can be used as a marker of microstructural tissue damage even in normal-appearing GM and WM within a vascular territory affected by high-grade carotid occlusive disease. Furthermore, the extent of damage correlates with the degree of hemodynamic failure measured by DSC perfusion parameters.

Erratum: Lattice Dynamics of EuO: Evidence for Giant Spin-Phonon Coupling [Phys. Rev. Lett. 116, 185501 (2016)]

This corrects the article DOI: 10.1103/PhysRevLett.116.185501.

Anomalous Lattice Dynamics of EuSi_{2} Nanoislands: Role of Interfaces Unveiled

We report a systematic lattice dynamics study of EuSi_{2} films and nanoislands by in situ nuclear inelastic scattering on ^{151}Eu and ab initio theory. The Eu-partial phonon density of states of the nanoislands exhibits anomalous excess of phonon states at low and high energies, not present in the bulk and at the EuSi_{2}(001) surface. We demonstrate that atomic vibrations along the island-substrate interface give rise to phonon states both at low and high energies, while atomic vibrations across the island-island interface result in localized high-energy phonon modes.

Lattice Dynamics of EuO: Evidence for Giant Spin-Phonon Coupling

Comprehensive studies of lattice dynamics in the ferromagnetic semiconductor EuO have been performed by a combination of inelastic x-ray scattering, nuclear inelastic scattering, and ab initio calculations. A remarkably large broadening of the transverse acoustic phonons was discovered at temperatures above and below the Curie temperature T_{C}=69  K. This result indicates a surprisingly strong momentum-dependent spin-phonon coupling induced by the spin dynamics in EuO.

High field electron paramagnetic resonance spectroscopy under ultrahigh vacuum conditions--a multipurpose machine to study paramagnetic species on well defined single crystal surfaces

A new ultrahigh vacuum (UHV) electron paramagnetic resonance (EPR) spectrometer operating at 94 GHz to investigate paramagnetic centers on single crystal surfaces is described. It is particularly designed to study paramagnetic centers on well-defined model catalysts using epitaxial thin oxide films grown on metal single crystals. The EPR setup is based on a commercial Bruker E600 spectrometer, which is adapted to ultrahigh vacuum conditions using a home made Fabry Perot resonator. The key idea of the resonator is to use the planar metal single crystal required to grow the single crystalline oxide films as one of the mirrors of the resonator. EPR spectroscopy is solely sensitive to paramagnetic species, which are typically minority species in such a system. Hence, additional experimental characterization tools are required to allow for a comprehensive investigation of the surface. The apparatus includes a preparation chamber hosting equipment, which is required to prepare supported model catalysts. In addition, surface characterization tools such as low energy electron diffraction (LEED)/Auger spectroscopy, temperature programmed desorption (TPD), and infrared reflection absorption spectroscopy (IRAS) are available to characterize the surfaces. A second chamber used to perform EPR spectroscopy at 94 GHz has a room temperature scanning tunneling microscope attached to it, which allows for real space structural characterization. The heart of the UHV adaptation of the EPR experiment is the sealing of the Fabry-Perot resonator against atmosphere. To this end it is possible to use a thin sapphire window glued to the backside of the coupling orifice of the Fabry Perot resonator. With the help of a variety of stabilization measures reducing vibrations as well as thermal drift it is possible to accumulate data for a time span, which is for low temperature measurements only limited by the amount of liquid helium. Test measurements show that the system can detect paramagnetic species with a density of approximately 5 × 10(11) spins/cm(2), which is comparable to the limit obtained for the presently available UHV-EPR spectrometer operating at 10 GHz (X-band). Investigation of electron trapped centers in MgO(001) films shows that the increased resolution offered by the experiments at W-band allows to identify new paramagnetic species, that cannot be differentiated with the currently available methodology.

Grey matter volumetric changes related to recovery from hand paresis after cortical sensorimotor stroke

Preclinical studies using animal models have shown that grey matter plasticity in both perilesional and distant neural networks contributes to behavioural recovery of sensorimotor functions after ischaemic cortical stroke. Whether such morphological changes can be detected after human cortical stroke is not yet known, but this would be essential to better understand post-stroke brain architecture and its impact on recovery. Using serial behavioural and high-resolution magnetic resonance imaging (MRI) measurements, we tracked recovery of dexterous hand function in 28 patients with ischaemic stroke involving the primary sensorimotor cortices. We were able to classify three recovery subgroups (fast, slow, and poor) using response feature analysis of individual recovery curves. To detect areas with significant longitudinal grey matter volume (GMV) change, we performed tensor-based morphometry of MRI data acquired in the subacute phase, i.e. after the stage compromised by acute oedema and inflammation. We found significant GMV expansion in the perilesional premotor cortex, ipsilesional mediodorsal thalamus, and caudate nucleus, and GMV contraction in the contralesional cerebellum. According to an interaction model, patients with fast recovery had more perilesional than subcortical expansion, whereas the contrary was true for patients with impaired recovery. Also, there were significant voxel-wise correlations between motor performance and ipsilesional GMV contraction in the posterior parietal lobes and expansion in dorsolateral prefrontal cortex. In sum, perilesional GMV expansion is associated with successful recovery after cortical stroke, possibly reflecting the restructuring of local cortical networks. Distant changes within the prefrontal-striato-thalamic network are related to impaired recovery, probably indicating higher demands on cognitive control of motor behaviour.

Pb5.0(1)In8.4(1)Bi1.6(1)S20, a new quaternary lead indium bismuth sulfide

The title phase, first detected in the early 1980s but hitherto unpublished, has been resynthesized and structurally characterized. Unambiguous determination of the chemical composition was not possible by structure analysis alone, but required additional analytical methods. The complex structure shows a close similarity to the structures of two related compounds, one known by the formula Pb(1.6)In(8)Bi(4)S(19) and the other being the ternary compound Pb(6)In(10)S(21). This is despite the fact that the three phases correspond to very different Pb:Bi ratios. A geometric mechanism is described by which the three structures can be transformed into each other, provided that the heavy atoms Pb and Bi are treated as equivalent.

The cystine/cysteine cycle: a redox cycle regulating susceptibility versus resistance to cell death

The glutathione-dependent system is one of the key systems regulating cellular redox balance, and thus cell fate. Cysteine, typically present in its oxidized form cystine in the extracellular space, is regarded as the rate-limiting substrate for glutathione (GSH) synthesis. Cystine is transported into cells by the highly specific amino-acid antiporter system xc-. Since Burkitt's Lymphoma (BL) cells display limited uptake capacity for cystine, and are thus prone to oxidative stress-induced cell death, we stably expressed the substrate-specific subunit of system xc-, xCT, in HH514 BL cells. xCT-overexpressing cells became highly resistant to oxidative stress, particularly upon GSH depletion. Contrary to previous predictions, the increase of intracellular cysteine did not affect the cellular GSH pool, but concomitantly boosted extracellular cysteine concentrations. Even though cells were depleted of bulk GSH, xCT overexpression maintained cellular integrity by protecting against lipid peroxidation, a very early event in cell death progression. Our results show that system xc- protects against oxidative stress not by elevating intracellular GSH levels, but rather creates a reducing extracellular environment by driving a highly efficient cystine/cysteine redox cycle. Our findings show that the cystine/cysteine redox cycle by itself must be viewed as a discrete major regulator of cell survival.

Transmission of the Ambystoma tigrinum virus to alternative hosts

Ambystoma tigrinum virus (ATV) is a lethal virus originally isolated from Sonora tiger salamanders Ambystoma tigrinum stebbinsi in the San Rafael Valley in southern Arizona. USA. ATV is implicated in several salamander epizootics. We attempted to transmit ATV experimentally to fish and amphibians by injection, water bath exposure, or feeding to test whether ATV can cause clinical signs of infection or be recovered from exposed individuals that do not show clinical signs. Cell culture and polymerase chain reaction of the viral major capsid protein gene were used for viral detection. Salamanders and newts became infected with ATV and the virus was recovered from these animals, but virus could not be recovered from any of the frogs or fish tested. These results suggest that ATV may only infect urodeles and that fish and frogs may not be susceptible to ATV infection.

Interpregnancy interval as a risk factor for placenta accreta

OBJECTIVE

To determine if the interval from a previous delivery or cesarean to the next conception differs between patients with abnormally adherent placentas as compared to those with normally implanted placentas.

METHODS

We identified all histologically confirmed placentas--accreta, increta, and percreta--at our hospital from 1992-1999. Subjects were excluded for primigravidity in the affected pregnancy or inability to identify matched controls. Cases were matched to the next three consecutive women delivering for maternal age (> or = 35 years or < 35 years), placenta previa (yes or no), prior cesarean (yes or no), prior uterine curettage (yes or no), and prior vaginal delivery (yes or no). The primary outcomes were delivery-to-conception and cesarean-to-conception intervals. Secondary outcomes included measures of maternal and neonatal morbidity.

RESULTS

Delivery-to-conception intervals for cases and controls were 37.1 +/- 18.7 months and 37.9 +/- 22.7 months, respectively (P = .91). Cesarean-to-conception intervals for cases and controls were 35.2 +/- 18.2 and 48.1 +/- 31.0 months, respectively (P = .35). Cases were more likely to require uterine curettage (54.5 vs 0%), hysterectomy (81.8 vs 0%), and transfusion (72.7 vs 0%), all P < .001. Subjects with accreta delivered earlier (31.7 +/- 9.4 vs 38.1 +/- 2.6 weeks, P = .054) and smaller infants (2,158 +/- 1,180 g vs 3,159 +/- 781 g, P = .006) who were more likely to have five-minute Apgar scores < 7 (18.2% vs 0%, P = .038).

CONCLUSIONS

Cesarean-to-conception intervals but not delivery-to-conception intervals are shorter in patients with abnormally adherent placentas. Placenta accreta is associated with significant maternal and perinatal morbidity.

[Liver transplantation in a small center: feasibility, efficacy and prospects]

Today, orthotopic liver transplantation is the treatment of choice for the end-stage of various liver diseases, and a 1-year survival rate of 80% and a 5-year survival rate of 70% in elective patients without tumor are reported in international surveys. The liver transplant programme of the Inselspital in Bern is small compared with international centres, which may raise questions about the results and the justification for such a programme. Over a period of 66 months, 62 liver transplantations were performed in 60 patients at the Inselspital. The hospital mortality was 3.3%, and the 2.5-year overall survival rate was 92% for elective cases without tumor. After a median follow-up of 30 months, 68% of all patients were re-integrated in housework or full- or part-time in their profession, and 83% were independent from the help of others. We conclude that a small liver transplant programme based only on routine resources can achieve results comparable to the international standards.

Clonal descent and microevolution of Neisseria meningitidis during 30 years of epidemic spread

Serogroup A meningococci of subgroups III, IV-1 and IV-2 are probably descended from a common ancestor that existed in the nineteenth century. The 10.5kb sequences spanning five distinct chromosomal loci, encoding cell-surface antigens, a secreted protease or housekeeping genes and intergenic regions, were almost identical in strains of those subgroups isolated in 1966, 1966 and 1917 respectively. During the subsequent two to three decades, all of these loci varied as a result of mutation, translocation or import of DNA from unrelated neisseriae. Thus, microevolution occurs frequently in naturally transformable bacteria. Many variants were isolated only once or within a single geographical location and disappeared thereafter. Other variants achieved genetic fixation within months or a few years. The speed with which sequence variation is either eliminated or fixed may reflect sequential bottlenecks associated with epidemic spread and contrasts with the results of phylogenetic analyses from bacteria that do not cause epidemics.

Allelic polymorphism and site-specific recombination in the opc locus of Neisseria meningitidis

The opc gene is widespread in epidemic and endemic Neisseria meningitidis, but most strains of certain epidemic clones (ET-37 complex, Cluster A4) and a few random endemic isolates lack an opc gene. Four percent of the 1148 bp that contain opc plus the surrounding intergenic region was polymorphic (18 alleles), and many of the alleles contained a 230 bp insertion at a fixed location in the intergenic region. The presence or absence of the insertion reflects site-specific recombination. The alleles are stably inherited within clonal groupings for up to at least 50 years, with rare cases of horizontal genetic exchange. Most statistical methods indicated significant intragenic recombination events within this dataset.

Different hemodynamic effects of celipropol and atenolol in patients with mild to moderate hypertension

The hemodynamic effects of celiprolol (CAS 56980-93-9), a betablocker with beta 1 antagonist and beta 2 agonist properties, were compared with those of atenolol (CAS 29122-68-7) in 12 patients with mild to moderately severe hypertension (diastolic BP 95-110 mmHg). Celiprolol and atenolol lead to a similar and significant reduction of systolic and diastolic blood pressure (p < 0.005). However, with celiprolol heart rate at rest was significantly less depressed then with atenolol (p = 0.004) and showed a distinctly less pronounced depression of heart rate with exercise (p = 0.004). Cardiac output at rest was reduced by 19% under atenolol, but was increased by 9% under celiprolol treatment; in this respect, the two medications differed significantly (p = 0.03). The adaptation of heart rate and cardiac output to exercise was better with celipropol as compared to atenolol treatment. The difference between arm arterial pressure and ankle occlusion pressure at rest was not significantly influenced by atenolol, whereas celiprolol treatment increased this difference by a mean of up to 16 mmHg (p = 0.009). This different effect on peripheral arterial circulation was even more pronounced after exercise. Both celiprolol and atenolol increased blood cell flow velocity in the nailfold capillaries, but this increases was statistically only significant with celiprolol (p = 0.047). These results demonstrate that the hemodynamic effects of celiprolol were significantly different from those of atenolol; celiprolol produces less bradycardia, increases cardiac output at rest and decreases peripheral arterial resistance.(ABSTRACT TRUNCATED AT 250 WORDS)

[Congenital heart defects: prevalence and course during the school years (8 to 16 years)]

In continuation of former studies regarding the first year of life and the preschool period, the prevalence and course of congenital heart disease in children during compulsory schooling has been studied. Compared with the preschool period, few cardiac defects are discovered, the prevalence up to 16 years of age being 9.9/1000. The mortality rate (2.7%) and also the rate of spontaneous normalization (4%) is significantly lower (compared to 18.7% and 21% respectively in the preschool period). Medical measures are needed less frequently, with 10 times fewer operations and 15 times fewer heart catheterizations being performed. Apart from the decline of hospital stays, checkups in the outpatient clinic also declined 3-4 times in comparison with the period between birth and school entry. School performance is very good. Only 4% of the children are unable to attend a normal school for cardiac reasons, and the percentage of pupils attending secondary school is higher than normal. In 5% of the children exercise tolerance is decreased due to the cardiac condition. In 85%, the quality of life is normal during the compulsory school period. Impairment is most often caused by additional non-cardiac malformations or very severe heart disease.

Microevolution within a clonal population of pathogenic bacteria: recombination, gene duplication and horizontal genetic exchange in the opa gene family of Neisseria meningitidis

Opacity (Opa) proteins are a family of antigenically variable outer-membrane proteins of Neisseria meningitidis. Even among clonally related epidemic meningococcal isolates, there is greater variation of Opa protein expression than can be accounted for by the opa gene repertoire of any individual strain. We characterized the opa genes of eight closely related isolates of serogroup A N. meningitidis (subgroup IV-1) from a recent meningitis epidemic in West Africa. DNA sequence analysis and Southern blot experiments indicated that changes occurred in the opa genes of these bacteria as they spread through the human population, over a relatively short period of time. Such changes in one or a few loci within a clonal population are referred to as microevolution. The distribution of sequences present in hypervariable (HV) regions of the opa genes suggests that duplication of all or part of opa genes into other opa loci changed the repertoire of Opa proteins that could be expressed. Additional variability in this gene family appears to have been introduced by horizontal exchange of opa sequences from other meningococcal strains and from Neisseria gonorrhoeae. These results indicate that processes of recombination and genetic exchange contributed to variability in major surface antigens of this clonal population of pathogenic bacteria.

[Sedation versus general anesthesia in pediatric endoscopy]

Upper endoscopy was performed in 567 patients: 237 under general anesthesia, 261 in intravenous sedation with midazolam and etomidat (mean dosage 0.26 mg/kg bodyweight), 69 without any premedication. In these many patients defended strongly and some investigations have to been interrupted. On the other hand general anaesthesia needed much more time and personnel and produced more costs. In our experience sedation with midazolam and etomidat is most comfortable for patient and endoscopist and the time needed is shorter than in general anaesthesia. Therefore we recommend this method even in therapeutic endoscopy, except only in sclerotherapy of esophageal varices.

[Electron microscopic studies of fimbriae and lectin phagocytosis of Salmonella typhimurium variety copenhagen (STMVC)]

On Salmonella typhimurium variatio copenhagen (STMVC) strains, isolated from pigeons with acute Salmonellosis, two types of fimbriae can be identified, depending on different growth conditions. In addition to the common 7 nm fimbriae we were able to demonstrate in the electron microscope, thin, curled fimbriae 3 nm in diameter which are characterized by a mannose-resistant hemagglutination. The simultaneous expression of both types of fimbriae on a single bacterial cell can be induced by transferring a microcolony from agar medium (3 nm fimbriae), to the surface of a nutrient broth (7 nm fimbriae) and continuing the incubation. One selected strain expresses only the thin fimbriae on nearly all the bacteria on an agar medium. These thin fimbriae seem to play a role in the lectinophagocytosis in macrophage cultures. The attachment of Salmonellae mediated by these fimbriae as well as the internalization of fimbriated cells by macrophages is shown in the electron microscope and discussed in respect to infection and immunization.

[Molecular biologic methods for epidemiological precision characterization of disease agents using Salmonella enteritidis from poultry as an example]

The principles of molecular biological methods for epidemiological investigation of infectious bacteria are described. They were applied for differentiating S. enteritidis isolates originating from poultry. Among the methods described are the determination of the chromosomal DNA fingerprints (BRENDA), the methods of multilocus enzyme electrophoresis, plasmid profiles, and the outer membrane protein as well as lipopolysaccharide pattern. It turned out, that S. enteritidis strains isolated before 1987, in 1988 and the ones originating from Great Britain did not differ in anyone of these criteria. Consequently one has to assume, that the strains recently causing problems originate from the population of S. enteritidis which had existed in poultry before.

[Colonoscopy: indications, procedure, results]

Colonoscopy in childhood is indicated as a valuable procedure mainly in rectal bleeding and suspected inflammatory bowel disease. Because of high efficiency and low complication rates this procedure should be used more often.

[Sonographic diagnosis of solid space-occupying abdominal lesions in childhood]

Between 1981 and May 1986 31 children with solid abdominal tumor masses were observed in our clinic. The first diagnostic procedure was a sonographic examination, followed by further radiological investigations if necessary. 30 cases were examined histologically; in one case the sonographic findings were confirmed by an angiography. The most frequent abdominal masses were neuroblastomas and Wilms tumors (7 cases each). A mesoblastic nephroma was diagnosed in 3 cases, a lymphoma, a hepatoblastoma and a rhabdomyosarcoma 2 times each. One time we found a pancreas carcinoma, a teratoma, a hemangiomatosis of the liver, a malignant Schwannoma, a Ewing sarcoma, an adenoma of the adrenal gland, a pheochromocytoma and an osteosarcoma. According to our own experience and recent reports in the literature it seems possible in most cases, to predict the correct diagnosis of solid abdominal masses using the informations of sonographic imaging. Sonography is a highly specific non-invasive diagnostic tool for planning treatment (e.g. early surgery, cytostatic therapy and/or radiation) of solid abdominal masses. Nevertheless the histological examination should be performed in every case to confirm the definitive diagnosis.

The mom gene of bacteriophage Mu: the mechanism of methylation-dependent expression

Transcription of the DNA modification gene (mom) of bacteriophage Mu requires methylation of three GATC sites upstream of the mom promoter by the Escherichia coli deoxyadenosine methylation function (Dam). The three sites map within a 40-bp segment termed region I. Small deletions, inversions, duplications and specific point mutations have been introduced in region I. Their effect on mom expression has been studied in dam+ and dam strains. Dam-dependent expression of the mom gene requires a specific arrangement of the three GATC sites and the presence of the methylated base in at least two of the three sites. We show that mom specific modification is regulated by a host protein. The Mom function is expressed in dam strains if they are defective in one component of the methylation-instructed mismatch correction system, mutH. We suggest that the product of mutH functions as a transcriptional repressor by binding to region I.