Relationship between Pharmacological Treatment Strategy and Cognitive Function in Geriatric Patients with Atrial Fibrillation

Background and question: Atrial fibrillation (AF) is the most common cardiac arrhythmia in the total population. The aim of this study is to determine how geriatric patients with AF are treated in terms of rhythm or rate control and whether a relationship between the type of treatment and Mini Mental Status (MMS) can be identified.

METHODS

In this monocentric, prospective, observational study, data including chronic medication as well as demographic parameters were collected from all patients in a geriatric department between April 2021 and April 2022. A 12-lead ECG as well as the Mini Mental Status were recorded for all patients as part of the admission routine, and a 24 h ECG was performed in selected patients on the basis of clinical indication.

RESULTS

At baseline, 715 out of 1914 patients (37.4%) had a known history of AF. Of these patients, 43 patients (6%) were on rhythm control therapy (RHY) and 672 (94%) were on rate control therapy (RATE). No difference in respect to MMS could be detected between RHY and RATE. However, linear regression analyses showed that age, HASBLED score, creatinine serum level, and an existing antiplatelet medication were associated with a negative influence on MMS, whereas oral anticoagulation (OAC) was associated with improved MMS, respectively (p < 0.05 for all).

CONCLUSION

The vast majority of geriatric patients with AF are treated with a rate control strategy. Oral anticoagulation is associated with better results in MMS, whereas patients who are treated with antiplatelet medication show worse results in MMS instead.

Stability of internal versus external fixation in osteoporotic pelvic fractures - a biomechanical analysis

INTRODUCTION

Osteoporosis-related fragility fractures of the pelvic ring (FFP) differ fundamentally from pelvic fractures in younger patients. However, very little is known about biomechanical stability of different osteosynthesis procedures addressing the anterior pelvic ring in these fractures. The aim of this study was to compare standard external fixation with internal fixation using a novel screw-and-rod system in osteoporotic fractures of the pelvic ring in terms of stiffness, plastic deformation and maximum load under cyclic loading in a human cadaveric model.

MATERIALS AND METHODS

A total of 18 embalmed osteoporotic cadaver pelvis specimens were randomized based on the T-score into a group for external fixation and a group for internal fixation. FFP type-IIB fractures were created. In addition to the external or internal fixator, a cement-augmented sacroiliac screw was implanted. Afterwards, axial cyclic loading was performed in a testing setup simulating one-leg stand.

RESULTS

Mean plastic deformation and stiffness both were significantly better in the internal fixation group than in the external fixation group (plastic deformation: 0.37 mm (SD: 0.23) versus 0.71 mm (SD: 0.26), p = 0.011; stiffness: 43.69 N/mm (SD: 18.39) versus 26.52 N/mm (SD: 9.76), p = 0.029). Maximum load did not differ significantly between internal fixator (506.3 N; SD: 129.4) and external fixator (461.1 N; SD: 147.4) (p = 0.515).

CONCLUSIONS

Submuscular internal fixation might be an interesting alternative to external fixation in clinical practice because of better biomechanical properties as well as several advantages in clinical use.

Comparative endocrine investigations in three bear species based on urinary steroid metabolites and volatiles

In order to improve breeding of in situ populations of bears, a comprehensive study of reproductive physiology in Brown (Ursus arctos), Spectacled (Tremarctos ornatus) and Giant panda bears (Ailuropoda melanoleuca) was performed. The objective was to perform non-invasive analyses of urinary and fecal steroid metabolites. In addition, we investigated the presence of reproduction-related urinary volatile substances of these bears that might trigger the reproductive behavior. Urinary estrogen concentrations, routinely used to monitor follicular activity in Giant panda, were inappropriate for monitoring follicular activity in Spectacled bear. In addition, no estrogen peak related to mating activity was observed in Brown bear. Further contrasting Giant panda, although urinary pregnanediol analyses failed to indicate luteal activity in either Spectacled or Brown bears, urinary (Spectacled bear) and fecal (Brown bear) concentrations of progesterone were an appropriate indicator of luteal activity. The Giant panda had volatile components (medium-chain fatty acids) in their urine that increased simultaneously with the seasonal increase of estrogens. These fatty acids were also detected in the Brown during estrus and Spectacled bear. Further studies on the behavioral relevance of these fatty acids are required to determine if they are pheromones.

A determinant for central nervous system persistence localized in the capsid of Theiler's murine encephalomyelitis virus by using recombinant viruses

The demyelinating process in Theiler's murine encephalomyelitis virus (TMEV) infection in mice requires virus persistence in the central nervous system. Using recombinant TMEV assembled between the virulent GDVII and less virulent BeAn virus cDNAs, we now provide additional evidence supporting the localization of a persistence determinant to the leader P1 (capsid) sequences. Further, recombinant viruses in which BeAn sequences progressively replaced those of GDVII within the capsid starting at the leader NH2 terminus suggest that a conformational determinant requiring homologous sequences in both the VP2 puff and VP1 loop regions, which are in close contact on the virion surface, might underlie persistence.