The Effect of Repeated Tense-Release Sequences on EMG and Self-Report of Muscle Tension: An Evaluation of Jacobsonian and Post-Jacobsonian Assumptions About Progressive Relaxation

This study tested three psychophysiological hypotheses generated from assumptions underlying post-Jacobsonian progressive relaxation techniques and assumptions that conflict with the rationale for Jacobson's progressive relaxation method. Twenty-eight subjects tensed and released tension from the forearm extensor and frontalis muscles during a series of trials interspersed with intervals of relaxation. Correlations between self-report of tension and EMG were moderate during relaxation, but did not increase across successive tense-release trials, thus indicating no increase in self-awareness of muscle tension. As predicted by Jacobson, paying attention to either muscle produced increased tension in the frontal area, but Jacobson's prediction of increases in forearm tension while paying attention to the forearm was not confirmed. Evidence was equivocal for the existence of the “pendulum effect” predicted by Bernstein and Borkovec. Tense-release trials produced gradual decreases in frontal EMG, but no changes in forearm EMG. Declines below baseline in self-reported muscle tension occurred only several minutes after the end of the tense-release trials, and did so for the forearm despite lack of EMG decreases in that area. This finding may reflect the influence of cognitive rather than muscular processes.     

Thrombozytose und Thrombozythämie-Symptom oder selbständiges Krankheitsbild?

Zusammenfassung Nach Besprechung der einschlägigen Literatur wird eine eigene Beobachtung einer zunächst als essentiell gedeuteten hämorrhagischen Thrombozythämie mit Plättchenzahlen zwischen 1,78 und 5,6 Mill./cmm bei einer 62jährigen Frau mitgeteilt, bei der sich späterhin eine leukämische Myelose entwickelte. Besonderheiten des Blutungstyps und der Gerinnungsbefunde werden diskutiert. Ein Einteilungsprinzip der verschiedenen Formen einer Thrombozytenvermehrung nach klinischen, genetischen und hämatologischen Gesichtspunkten wird vorgeschlagen.     

Changes in pulmonary mechanics after fiberoptic bronchoalveolar lavage in mechanically ventilated patients

Objective: We prospectively assessed the impact of bronchoalveolar lavage (BAL) on respiratory mechanics in critically ill, mechanically ventilated patients. Study design: Mechanically ventilated patients underwent BAL of one lung segment using 5 × 20 ml of sterile, physiologic saline with a temperature of 25–28 °C. The fractional inspired oxygen was increased to 1.0, but ventilator settings were otherwise left unchanged. Static pulmonary compliance, pulmonary resistance, alveolar ventilation, and serial dead space were measured 60 min and 2 min before and 8, 60, and 180 min after BAL to assess the consequences of the procedure. In addition, blood gases [partial pressure of carbon dioxide in arterial blood (PaCO₂) and arterial oxigen tension (PaO₂)], hemodynamic variables (heart rate, systolic and diastolic blood pressure), and body temperature were recorded at the same time points. Setting: Intensive care unit of a university hospital. Patients: 18 consecutive critically ill, mechanically ventilated patients. Results: Pulmonary compliance decreased by 23 % (p < 0.05) and pulmonary resistance increased by 22 % (p < 0.05) shortly after BAL. The changes in pulmonary compliance and resistance were more than 30 % in one third of the patient population. One hour after the procedure, PaO₂ was significantly lower and PaCO₂ significantly higher than before the procedure. Three hours after the procedure, pulmonary resistance returned to pre-BAL values but compliance remained 10 % below baseline values (p < 0.05). Conclusion: BAL in mechanically ventilated patients is associated with deterioration of pulmonary mechanics and function. Received: 19 January 1998 Accepted: 20 August 1998     

Real world usability analysis of two augmented reality headsets in visceral surgery

Recent developments in the field of augmented reality (AR) have enabled new use cases in surgery. Initial set‐up of an appropriate infrastructure for maintaining an AR surgical workflow requires investment in appropriate hardware. We compared the usability of the Microsoft HoloLens and Meta 2 head mounted displays (HMDs). Fifteen medicine students tested each device and were questioned with a variant of the System Usability Scale (SUS). Two surgeons independently tested the devices in an intraoperative setting. In our adapted SUS, ergonomics, ease of use, and visual clarity of the display did not differ significantly between HMD groups. The field of view (FOV) was smaller in the Microsoft HoloLens than the Meta 2 and significantly more study subjects (80% vs. 13.3%; P < 0.001) felt limited through the FOV. Intraoperatively, decreased mobility due to the necessity of an AC adapter and additional computing device for the Meta 2 proved to be limiting. Object stability was rated superior in the Microsoft HoloLens than the Meta 2 by our surgeons and lead to increased use. In summary, after examination of the Meta 2 and the Microsoft HoloLens, we found key advantages in the Microsoft HoloLens which provided palpable benefits in a surgical setting.     

Hepatitis A antibodies in young hemophiliacs

The proof of antibodies against the hepatitis A-virus (anti-HAV) is a frequent finding in substituted haemophiliacs. Anti-HAV is apparently not the expression of an actively acquired immunity, but might have been transmitted above all passively by means of the plasma preparations. Among 68 haemophilic children and adolescents anti-HAV was proved 22 times, in 33 boys of about the same age with undisturbed blood coagulation only twice. Of 40 cryoprecipitate 22 were anti-HAV-positive. Thus as a side-effect of the substitution therapy a protective effect against a hepatitis A-virus infection develops--at least partly.     

Designing tracers for PET imaging of the urokinase‐type plasminogen activator receptor from a cyclic uPA‐derived peptide: first in vitro evaluations

The treatment of cancer remains a major challenge, especially after tumour cell dissemination and metastases formation. Expression of the urokinase‐type plasminogen activation system including urokinase (uPA) and its receptor (uPAR) has been associated with the complex process of cell migration, a tumour's invasive potential as well as a reduced overall and disease‐free survival of patients with solid cancers and haematological disorders. A cyclic peptide cyclo[21,29][d ‐Cys²¹,Cys²⁹]‐uPA_21‐30 was designed from the growth factor‐like domain (GFD) of urokinase whose binding to uPAR was found to inhibit tumour growth and spread of human ovarian cancer cells in mice. With the aim of visualising uPAR expression using PET imaging to attempt an estimate on the tumour's aggressiveness, the cyclic peptide was modified with an either C‐ or N‐terminally attached variable spacer and chelator. The free ligands were evaluated for their binding affinities to the isolated human uPAR and labelled with ⁶⁸Ga and ¹⁷⁷Lu to assess their lipophilicities and stabilities in human serum. Although retaining the full binding potential displayed by cyclo[21,29][d ‐Cys²¹,Cys²⁹]‐uPA_21‐30 to its target was found to be a challenging task upon both C‐ and N‐terminal modification, chelator‐bearing ligands were identified that can serve as promising starting points in the development of uPAR‐addressing PET tracers.     

Teburu—Open source 3D printable bioreactor for tissue slices as dynamic three‐dimensional cell culture models

Three‐dimensional tissue cultures are important models for the study of cell‐cell and cell‐matrix interactions, as well as, to investigate tissue repair and reconstruction pathways. Therefore, we designed a reproducible and easy to handle printable bioreactor system (Teburu), that is applicable for different approaches of pathway investigation and targeted tissue repair using human tissue slices as a three‐dimensional cell culture model. Here, we definitively describe Teburu as a controlled environment to reseed a 500‐µm thick decellularized human liver slice using human mesenchymal stroma cells. During a cultivation period of eight days, Teburu, as a semi‐open and low consumption system, was capable to maintain steady pH and oxygenation levels. Its combination with additional modules delivers an applicability for a wide range of tissue engineering approaches under optimal culture conditions.