A new method to evaluate the effects of shear on the skin

Currently, pressure ulcer preventive strategies focus mainly on pressure redistribution. Little attention is paid to reduce the harmful effects of shear‐force, because little is known about pathophysiological aspects of shear‐force. Even today, no method to measure the effects of shear‐force on the skin is available. Therefore, the aim of this study was to investigate the response to shear‐forces in terms of analyzing a noninvasive biomarker and reactive hyperemic parameter measured at the skin of healthy participants. A physical model was developed to produce a combination of pressure and shear or pressure alone on the skin. Ten healthy male participants were included and pressure (3.9 kPa) and a combined loading of pressure and shear (2.4 kPa + 14.5 N) was applied at the volar aspect of the forearms for 15 and 30 minutes. A Sebutape sample was used to collect IL‐1α and total protein (TP) noninvasively. The reactive hyperemic parameter was derived from a laser Doppler flowmeter. The increase in IL‐1α/TP‐ratio after a combined loading of pressure and shear for 30 minutes of 6.2 ± 2.5 was significantly higher compared with all other test conditions (p < 0.05). The increase in cutaneous blood cell flux was already significantly higher when a combined loading of pressure and shear was applied for 15 minutes compared with pressure alone. These results shows that the IL‐1α/TP‐ratio and cutaneous blood cell flux can be used as robust measures of the effect of shear‐force on skin in humans. Therefore, this model can be used to evaluate materials aimed at the reduction of shear.     

Erectile Impotence in Chronic Alcoholics

Erectile impotence is a common complaint in alcoholics, but its mechanism is unknown. We have studied nocturnal penile erection in 13 alcoholics who complained of impotence. Seven had normal erections and their impotence was therefore psychogenic. Six were found to have diminished or absent nocturnal erections. Plasma concentrations of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were elevated in this latter group, with the exception of one patient who had only raised FSH. They also had more evidence of neurological damage than the other seven alcoholics, and two had evidence of damage to the parasympathetic nervous system. Investigation of erection during sleep in alcoholic patients with impotence may be useful in differentiating clinically between patients with psychogenic causes and patients with organic causes of impotence.     

Five-year follow-up of left ventricular diastolic function in systemic sclerosis patients: Determinants of mortality and disease progression

Objectives

In systemic sclerosis (SSc), left ventricular diastolic dysfunction reflects primary myocardial involvement of the disease. We aimed to assess the abnormalities of the diastolic function, analyze the characteristics of the disease progression, and investigate the prognostic value of diastolic dysfunction in SSc patients.

Patients and methods

A total of 34 SSc patients (57 ± 12 years, 31 female) were involved in the study. The following traditional or tissue Doppler parameters of left ventricular diastolic function were obtained: E/A, lateral E?, E/E?, left ventricular mass index (LVM index), and maximal left atrial (LA) volume index. Measurements were repeated after 5.5 years.

Results

At baseline, diastolic dysfunction was found in 62% of the SSc patients. Follow-up time was 5.4 ± 1.2 years. A total of 6 patients died of heart failure. In univariate Cox regression analysis, age (HR = 1.08, p < 0.05), LVM index (HR = 1.07, p < 0.01), lateral E? (HR = 1.57, p = 0.05), and LA volume index (HR = 1.11, p < 0.01) were predictors of survival. During the follow-up, significant increase in LA volume index (27.5 ± 9.7 vs. 35.4 ± 10.6 cm³/m², p < 0.001) and E/E? was found (7.6 ± 2.5 vs. 8.7 ± 3.8, p < 0.05) while E? did not change (9.6 ± 2.6 vs. 9.2 ± 1.9 cm/s, NS). The increase in LA volume index showed positive correlation (r = 0.46, p < 0.05) while the decrease in E? values showed negative correlation (r = −0.54, p < 0.01) with the duration of the SSc.

Conclusion

In SSc patients, left ventricular diastolic dysfunction is highly prevalent and is associated with increased risk of mortality. Our data suggest that in the advanced phase of the disease, the myocardial fibrotic processes burns out while the increase of the filling pressure progresses continuously.     

Muscle‐specific kinase antibodies: A novel cause of peripheral nerve hyperexcitability?

Introduction: Antibodies that target the postsynaptic neuromuscular junction (NMJ) protein, muscle‐specific kinase (MuSK), have been associated with myasthenia gravis (MG), often with cramps and fasciculations, after administration of acetylcholinesterase inhibitors (AChE‐I). Methods: In this report, 2 patients are described with elevated MuSK antibodies and evidence of peripheral nerve hyperexcitability (PNH) unrelated to AChE‐I medication. Results: Patient 1 presented with facial neuromyotonia and fasciculations, without overt weakness. EMG studies demonstrated myokymic discharges in facial muscles, with bursts of discharges after voluntary activation, and widespread fasciculation potentials in limb muscles. Patient 2 presented with bulbar weakness and fasciculations in the tongue and limbs, initially diagnosed as bulbar‐onset amyotrophic lateral sclerosis. Subsequent investigation identified the presence of MuSK antibodies. Conclusions: We hypothesize that MuSK antibodies may induce these phenotypes through disruptive actions at the NMJ, in particular the binding of acetylcholinesterase (AChE) to MuSK via its collagen Q (ColQ) tail, producing a reduction in synaptic AChE activity. Muscle Nerve 48:819–823, 2013