The (in)effectiveness of anticipatory vibrotactile cues in mitigating motion sickness

The introduction of (fully) automated vehicles has generated a re-interest in motion sickness, given that passengers suffer much more from motion sickness compared to car drivers. A suggested solution is to improve the anticipation of passive self-motion via cues that alert passengers of changes in the upcoming motion trajectory. We already know that auditory or visual cues can mitigate motion sickness. In this study, we used anticipatory vibrotactile cues that do not interfere with the (audio)visual tasks passengers may want to perform. We wanted to investigate (1) whether anticipatory vibrotactile cues mitigate motion sickness, and (2) whether the timing of the cue is of influence. We therefore exposed participants to four sessions on a linear sled with displacements unpredictable in motion onset. In three sessions, an anticipatory cue was presented 0.33, 1, or 3 s prior to the onset of forward motion. Using a new pre-registered measure, we quantified the reduction in motion sickness across multiple sickness scores in these sessions relative to a control session. Under the chosen experimental conditions, our results did not show a significant mitigation of motion sickness by the anticipatory vibrotactile cues, irrespective of their timing. Participants yet indicated that the cues were helpful. Considering that motion sickness is influenced by the unpredictability of displacements, vibrotactile cues may mitigate sickness when motions have more (unpredictable) variability than those studied here.

PLK2 is a novel regulator of osteopontin-driven fibrosis and diastolic dysfunction in permanent atrial fibrillation

Background and aim

Atrial fibrillation (AF) is frequently accompanied by cardiac fibrosis and diastolic heart failure. Due to the heterogeneous nature and complexity of fibrosis, the knowledge of the underlying pathomechanisms is limited. Thus, effective antifibrotic pharmacotherapy is missing. The objective of this study was to decipher the role of polo-like kinase 2 (PLK2) in the pathogenesis of cardiac fibrosis and left ventricular diastolic dysfunction. We put particular emphasis on the identification of profibrotic downstream targets of PLK2, which can serve as therapeutic targets.

Methods and results

This study was based on human atrial tissue biopsies and peripheral blood samples, a PLK2 knockout mouse model, a canine tachy-pacing model and specific pharmacological interventions on cardiac fibroblasts. In human atrial AF tissue samples, PLK2 was 50% downregulated by hypoxia-induced promoter methylation compared to sinus rhythm (SR) control. Confirmatory analysis of a canine tachy-pacing model showed PLK2 downregulation exclusively in the atria but not in the ventricles. Specific pharmacological inhibition as well as genetic deletion of PLK2 led to a striking myofibroblast phenotype. Discovery proteomics revealed that the global knockout of PLK2 resulted in de novo secretion of the inflammatory cytokine osteopontin (OPN) in cardiac fibroblasts and concomitant ventricular fibrosis in the PLK2 knockout mouse model. An ELISA analysis of peripheral blood samples of AF patients with electrophysiologically proven fibrosis, confirmed significantly increased OPN plasma concentrations compared to SR and non-fibrosis AF controls. Consequently, echocardiography on PLK2 KO mice revealed left ventricular diastolic dysfunction, tachycardia and fibrosis-typical surface ECG anomalies (PQ and QRS prolongation). Mechanistically, we identified the ERK1/2 signaling pathway as the molecular link between reduced expression of PLK2 and elevated osteopontin transcription. In a reverse translational attempt, we successfully tested the capability of 5-amino-salicylic acid (5-ASA) to inhibit osteopontin transcription and to reverse a TGF-β-induced myofibroblast phenotype in vitro. Currently the long-term administration of 5-ASA is tested in PLK2 knockout mice to evaluate the therapeutic potential to prevent cardiac fibrosis and diastolic heart failure development.

Conclusion and clinical impact

We identified PLK2 as an epigenetically regulated kinase involved in the pathophysiology of fibrosis in AF. PLK2 knockout mice can serve as a model of diastolic heart failure wherein OPN is a promising therapeutic target. Our results strengthen the current hypothesis that atrial fibrillation is not only an ion channel disease but a complex systemic disorder. Restoration of physiological PLK2 expression and blockade of osteopontin release with 5-ASA may constitute valuable new drug targets for the prevention and treatment of fibrosis and diastolic heart failure in AF.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Faculty of Medicine, Carl Gustav Carus, Dresden, “MeDDrive Start” Grant

Family involvement with the diabetes regimen in young people: the role of adolescent depressive symptoms

AIMS

In young people with Type 1 diabetes, depressive symptoms and shared responsibility for management of diabetes impact upon diabetes management and control. However, the simultaneous effects of both depressive symptoms and parental involvement on diabetes self-care and glycaemic control have not been examined. Thus, the aim of the current study was to examine the relationships between parental involvement and adolescent depressive symptoms in predicting blood glucose monitoring and glycaemic control.

METHODS

One hundred and fifty young people with Type 1 diabetes (mean age 15.3 years) and their parents completed responsibility sharing and depressive symptom assessments, meter assessment of blood glucose monitoring and HbA(1c) at baseline and then 6, 12 and 18 months.

RESULTS

Parental involvement affected HbA1c through blood glucose monitoring only at low levels of adolescent depressive symptoms (score ≤ 6), which made up only 20% of the sample. In the presence of more depressive symptoms, parental involvement no longer was related to HbA1c through blood glucose monitoring. This was the relationship in the majority of the sample (80%).

CONCLUSIONS

While most young people in this sample are not showing evidence of high levels of depressive symptoms, even modest levels of distress interfere with parental involvement in diabetes management. By addressing adolescent depressive symptoms, interventions promoting parental involvement in these families may be more effective.

Scorecard endoscopy: a pilot study to assess basic skills in trainees for upper gastrointestinal endoscopy

BACKGROUND

The development of training models and structured training courses for endoscopic techniques provides practical experience. To assess individual performance and progress in this training we developed and tested a scorecard system.

METHODS

Three test groups were compared: group 1, ten physicians without previous endoscopic experience; group 2, ten students, without endoscopic experience; group 3, a control group of experienced endoscopists. Groups 1 and 2 underwent 1 week of training with a theoretical introduction and practical demonstrations. They were assessed by the scorecard daily by an experienced tutor. The individual scores and learning curves of the two beginner groups were compared with those of the expert group using a biosimulation model was used.

RESULTS

Each participant improved significantly during the 1-week course. Mean scores on the first day in groups 1-3 were, respectively, 26.7+/-10.7, 33.4+/-5.3, and 72.0+/-5.8, and on day 6 they were 62.2+/-6.6, 63.4+/-7.6, and 86.6+/-4.3. The difference between group 3 and the other two groups was significant but not that between groups 1 and 2.

CONCLUSIONS

Training in endoscopy can be assessed using our training model and our scorecard protocol, which distinguishes between various levels of experience. In physicians beginning in the field of gastrointestinal endoscopy this approach could help to reduce risks to patients, shorten learning curves, and exclude unskilled individuals from further fruitless interventions.

Sertraline treatment of posttraumatic stress disorder: results of 24 weeks of open-label continuation treatment

BACKGROUND

Posttraumatic stress disorder (PTSD) is typically associated with a high degree of chronicity, comorbidity, and psychosocial disability. The efficacy of sertraline in the acute treatment of PTSD has been confirmed based on the results of 2 large, placebo-controlled studies, but almost no prospective long-term treatment studies have been reported.

METHOD

One hundred twenty-eight patients who completed 12 weeks of double-blind, placebo-controlled, acute-phase treatment for DSM-III-R-defined PTSD with sertraline were continued into a 24-week open-label continuation phase. Efficacy was evaluated using the endpoint change in the 17-item Clinician Administered PTSD Scale Part 2 (CAPS-2) severity score, the 15-item patient-rated Impact of Event Scale, and the Clinical Global Impressions-Improvement and -Severity of Illness scales as primary outcome measures. Treatment response was defined as > or =30% decrease in the CAPS-2 total severity score (compared with acute-phase baseline score) and a Clinical Global Impressions-Improvement score of 1 or 2.

RESULTS

Ninety-two percent of acute-phase responders maintained their response during the full 6 months of continuation treatment. In addition, 54% of acute-phase nonresponders converted to responder status during continuation therapy. Over the 36-week course of acute and continuation therapy, 20% to 25% of the improvement in the CAPS-2 severity score occurred during the continuation phase. Sertraline was well tolerated, with 8.6% of patients discontinuing due to adverse events. A high pretreatment CAPS-2 score (> 75) predicted a longer time to response and a greater likelihood that response occurred after 12 weeks of acute treatment.

CONCLUSION

The acute efficacy of sertraline is sustained in the vast majority of patients, and at least half of nonresponders to acute treatment will eventually respond to continued treatment.

Interleukin-2-based immunotherapy for the treatment of metastatic renal cell carcinoma: an analysis of 203 consecutively treated patients

PURPOSE

This article analyzes the long-term results of 203 consecutive patients with metastatic renal cell carcinoma who were treated with various recombinant interleukin-2 (rIL-2) -based immunotherapy regimens, and describes factors that may influence response to therapy and long-term survival.

PATIENTS AND METHODS

The response and survival of 203 patients with metastatic renal cell carcinoma treated consecutively between July 1987 and October 1995 at the UCLA Medical Center Kidney Cancer Program with rIL-2-based immunotherapy were analyzed. Patients were divided into four groups: (1) no prior nephrectomy (n = 24), (2) nephrectomy > 6 months prior to rIL-2 therapy (n = 76), (3) nephrectomy < or = 6 months prior to rIL-2 therapy (n = 47), and (4) nephrectomy followed by treatment with rIL-2 and tumor-infiltrating lymphocytes +/- interferon-alpha (n = 56). Response and survival for each of these patient groups and survival per response to therapy were compared.

RESULTS

The overall median survival for all patients was 18 months, and survival at 1, 2, and 3 years after therapy was 61%, 40%, and 31% percent, respectively. A total of 12 patients (6%) achieved a complete response, and all were alive at 3 years. Of 36 patients (18%) who achieved a partial response and 41 patients (20%) with stable disease, 3-year survival was 37% and 50%, respectively. The survival of patients with a partial response or stable disease was significantly better than that of patients who exhibited progressive disease. Patients with nephrectomy > 6 months prior to rIL-2 therapy had a 46% 3-year survival rate, compared with a 9% 3-year survival rate for patients with nephrectomy < or = 6 months prior to rIL-2 therapy and a 4% 3-year survival rate for patients with no nephrectomy. Patients treated with tumor-infiltrating lymphocytes had a 38% 3-year survival rate, which was also significantly better than patients treated with nephrectomy < or = 6 months prior to rIL-2 therapy or with no nephrectomy.

CONCLUSION

This analysis demonstrated that rIL-2-based therapy offers a significant survival benefit to patients with advanced metastatic renal cell carcinoma, compared with historical controls. Furthermore, we have shown that nephrectomy > 6 months prior to rIL-2 therapy and nephrectomy followed by treatment with tumor-infiltrating lymphocytes/rIL-2 +/- interferon-alpha was associated with the greatest survival benefit. Tumor response to rIL-2-based therapy and time from nephrectomy to treatment were the most important predictors of survival. Randomized studies in a large group of patients are needed to confirm these observations.

Distinct association of transferrin receptor with HLA class I molecules on HUT-102B and JY cells

The topological relationship of transferrin receptor (TfR) has been studied relative to the heavy and light chains of the HLA class I molecules, class II molecules, interleukin-2 receptor alpha-chain and ICAM-1 molecule in the plasma membrane of HUT-102B2 T and JY B lymphoblastoid cell lines using the flow cytometric fluorescence energy transfer technique (FCET). The effect of different growing conditions (logarithmic and plateau phases) on the relative surface density of the receptors and the lateral organization of the TfR was also studied. The TfR showed a high degree of self-association on the surface of both cell lines regardless of the growing phase. TfR was in close vicinity to HLA class I heavy and light chains on HUT-102B cells in both plateau and logarithmic phases, while it was not associated with HLA class I on the surface of JY cells. HLA class II molecules form a cluster with TfR on HUT-102B cells, while only a modest association was found on JY cells, and only in the logarithmic phase. The possible explanation of this distinct association and a two dimensional model of the antigen and receptor distributions are presented in this paper.

Characterization of infectious molecular clones of equine infectious anaemia virus

We have recovered five infectious molecular clones of the lentivirus equine infectious anaemia virus (EIAV). The clones were recovered from fetal equine kidney (FEK) cells infected with a virulent, cell culture-adapted virus stock (designated PV) and have been characterized at a molecular level. Each clone has unique envelope and long terminal repeat (LTR) sequences. We further investigated LTR sequence variation in the PV stock using PCR amplification to obtain additional LTR clones from infected FEK cells and from peripheral blood mononuclear cells (PBMCs) from animals experimentally infected with PV. Sequence analysis of resulting clones indicates a selection for different LTR populations in pony PBMCs compared to FEK cells. Finally, we observed that the cloned EIAV proviruses did not remain infectious when maintained in a derivative of pBR322. However, two proviruses have been stably maintained in a low copy number vector (pLG338-SPORT).

Physostigmine-induced epinephrine release in patients with affective disorder

Infusion of the cholinomimetic drug physostigmine led to profound increases in serum epinephrine levels and slight increases in serum norepinephrine levels among 38 patients with affective disorder and 22 control subjects. Preliminary results suggest that physostigmine may induce relatively blunted increases in serum epinephrine levels in patients with affective disorders.

The antiarrhythmic effect of PGE2 on premature ventricular beats (PVBs) in man

In 10 patients with premature ventricular beats (PVBs) we investigated the influence of PGE2 infusion on ventricular arrhythmias, arterial blood pressure, heart rate and systolic time intervals. An infusion of PGE2 in doses of 0.01, 0.02 and 0.04 microgram/kg/min, each for 10 min, did not change the blood pressure, heart rate and systolic time intervals. The incidence of PVBs decreased in a dose-dependent manner in 7 out of 10 patients, and in two of them PVBs were absolutely abolished. In one patient the incidence of PVBs was reduced dose independently, and in two patients at the beginning of infusion of PGE2 the incidence of PVBs was reduced, but the incidence of PVBs increased again although the infusion dose was doubled. In all patients the incidence of PVBs increased again when the infusion of PGE2 was stopped. Our findings demonstrate that PGE2 has antiarrhythmic properties in man.

Influence of acetylsalicylic acid on acute circulatory effects of the beta-blocking agents pindolol and propranolol in humans

In ten hospitalized, hypertensive male patients (WHO stage I or II) an acetylsalicylic acid (ASA) pretreatment (p.o. 5.0 g/24 h) prevented the acute blood pressure (BP) lowering effect of pindolol (1 mg i.v.) as compared with a placebo pretreatment. Similarly in six other hospitalized male patients (four normotensive, two slightly hypertensive) a single dose of ASA (1.0 or 1.5 g orally), which alone tended to raise the BP, reduced the decrease in systolic BP and led to an increase in diastolic BP following propranolol (5 mg i.v.). The ASA pretreatment did not affect the decrease in heart rate and cardiac contractility (measured by systolic time intervals) after the application of pindolol and propranolol, respectively. In conformity with data in the literature, the results suggest a possible connection between endogenous prostaglandins and the hypotensive, but not negative chronotropic and inotropic activity of the beta-blocking agents investigated.

Patent ductus arteriosus in preterm infants with idiopathic respiratory distress syndrome. Radiographic and echocardiographic evaluation

Clinical, radiographic, echocardiographic and operative findings were evaluated in 55 preterm infants with idiopathic respiratory distress syndrome (IRDS) complicated by patent ductus arteriosus (PDA). Pulmonary plethora was detected prior to age seven days in 52 infants, and prior to murmur detection in 42 infants. In those with large shunts, only 35% had cardiomegaly while 78% had a significant increase in cardiothoracic ratio (C/T) on sequential radiographs. Moreover, within 48 hours after ligation, 91% of infants had a significant decrease in C/T. Echocardiographic left atrial to aortic ratio (LA/Ao) was elevated in 71% with large shunts. In one patient with a large shunt there was neither a sequential increase in C/T nor an increased LA/Ao. Severity of left-to-right shunting across a PDA in the newborn was reliably gauged by combined radiographic and echocardiographic evaluation. Either modality alone failed to reflect the presence of a large volume shunt in a number of infants.

Comparative study of the cardiac and peripheral vascular effects of strophantin K and lanatoside C in coronary heart disease

The effects of intravenous strophanthin K (0.125 and 0.25 MG) and lanatoside C (0.4, 0.8 and 1.6 mg) on systolic time intervals (STI) and impedance plethysmographic (IP)P values were studied in ten patients with compensated coronary heart disease. The heart rate decreased significantly during a two-hour study in the lying position after both glycosides and placebo; the systemic blood pressure remained unchanged. Electromechanical systole (QS2), left ventricular ejection time (LVET) and preejection period (PEP), corrected for heart rate (QS2I, LVETI, PEPI), showed no change after placebo. The glycosides caused no change in LVETI. QS2I was significantly shortened only after lanatoside C 1.6 mg. PEPI and ICT were significantly shortened by both doses of strophanthin K and lanatoside C; the effects were dose-related. Taking into consideration the effects of cardiac glycosides on STI, use of the index ICT/QS1, the quotient of isovolumic contraction time and electro-mechanical delay, is proposed, because it showed quite sensitively the increase in myocardial contractility after digitalis. The effect of strophanthin K could be detected 10 minutes, and that of lanatoside C 30-40 minutes, after injection. The amplitude of the IP curve and the relative pulse volume showed positive and negative changes without any trend after administration of placebo or glycoside. The data suggests that the usual therapeutic doses of these cardiac glycosides do not cause significant changes in the peripheral circulation in patients with compensated coronary heart disease, but their action on STI is quite marked, showing a positive inotropic effect.