Neural correlates of self‐injurious behavior in Prader–Willi syndrome

Individuals with Prader–Willi syndrome (PWS), a genetic disorder caused by mutations to the q11‐13 region on chromosome 15, commonly show severe skin‐picking behaviors that can cause open wounds and sores on the body. To our knowledge, however, no studies have examined the potential neural mechanisms underlying these behaviors. Seventeen individuals with PWS, aged 6–25 years, who showed severe skin‐picking behaviors, were recruited and scanned on a 3T scanner. We used functional magnetic resonance imaging (fMRI) while episodes of skin picking were recorded on an MRI‐safe video camera. Three participants displayed skin picking continuously throughout the scan, three participants did not display skin picking, and the data for one participant evidenced significant B0 inhomogeneity that could not be corrected. The data for the remaining 10 participants (six male, four female) who displayed a sufficient number of picking and nonpicking episodes were subjected to fMRI analysis. Results showed that regions involved in interoceptive, motor, attention, and somatosensory processing were activated during episodes of skin‐picking behavior compared with nonpicking episodes. Scores obtained on the Self‐Injury Trauma scale were significantly negatively correlated with mean activation within the right insula and left precentral gyrus. These data indicate that itch and pain processes appear to underlie skin‐picking behaviors in PWS, suggesting that interoceptive disturbance may contribute to the severity and maintenance of abnormal skin‐picking behaviors in PWS. Implications for treatments are discussed. Hum Brain Mapp 36:4135–4143, 2015. © 2015 Wiley Periodicals, Inc.     

What is the optimal serum potassium level in cardiovascular patients?

Humans are prone to sodium overload and potassium depletion. This electrolyte imbalance is important in the pathogenesis of cardiovascular disease and sudden cardiac death. Avoiding hypokalemia is beneficial in several cardiovascular disease states including acute myocardial infarction, heart failure, and hypertension. The evidence highlighting the importance of potassium homeostasis in cardiovascular disease and possible mechanisms explaining potassium's benefits are reviewed. Targets for serum potassium concentration are suggested.     

The role of urethral samples in the diagnosis of gonorrhoea in women

We studied the value of carrying out urethral samples in women to diagnose gonorrhoea. All cases of genital gonorrhoea in women were identified (between 1 October 2000 and 30 September 2001) at the Whittall Street Clinic and the genitourinary medicine department at the Coventry and Warwickshire Hospital. Two hundred and twenty-four cases of female urethral gonorrhoea were identified. In 20 cases (6.3%) the urethra was the sole site of the infection. At the Whittall Street Clinic, we had to carry out 643 urethral samples in order to treat one additional case of gonorrhoea. On the other hand, 1204 urethral samples were requested to treat one additional case of female gonorrhoea at the Coventry and Warwickshire Hospital. In both units, use of the Gram-stained urethral smear permitted early treatment in only 1.8% of cases of genital gonorrhoea. Units with low prevalence of gonorrhoea should consider abandoning urethral samples for the diagnosis of gonorrhoea in women.     

Quantification of cellular viability by automated microscopy and flow cytometry

Cellular viability is usually determined by measuring the capacity of cells to exclude vital dyes such as 4′,6-diamidino-2-phenylindole (DAPI), or by assessing nuclear morphology with chromatinophilic plasma membrane-permeant dyes, such as Hoechst 33342. However, a fraction of cells that exclude DAPI or exhibit normal nuclear morphology have already lost mitochondrial functions and/or manifest massive activation of apoptotic caspases, and hence are irremediably committed to death. Here, we developed a protocol for the simultaneous detection of plasma membrane integrity (based on DAPI) or nuclear morphology (based on Hoechst 33342), mitochondrial functions (based on the mitochondrial transmembrane potential probe DiOC₆(3)) and caspase activation (based on YO-PRO^®-3, which can enter cells exclusively upon the caspase-mediated activation of pannexin 1 channels). This method, which allows for the precise quantification of dead, dying and healthy cells, can be implemented on epifluorescence microscopy or flow cytometry platforms and is compatible with a robotized, high-throughput workflow.     

Intra-oral myofascial therapy for chronic myogenous temporomandibular disorders: a randomized, controlled pilot study

Objectives

Studies investigating the efficacy of intra-oral myofascial therapies (IMT) for chronic temporomandibular disorder (TMD) are rare. The objective of this randomized, controlled pilot study was to compare the effects of IMT and the addition of self-care and education over 6 months on four common TMD outcome measures: inter-incisal opening range, jaw pain at rest, jaw pain upon opening, and jaw pain upon clenching.

Participants

Thirty myogenous TMD participants between the ages of 18 and 50 years, experiencing chronic jaw pain of longer than 3-month duration, were recruited for the present study.

Intervention

Included patients were randomized into one of three groups: (1) IMT consisting of two treatment interventions per week for 5 weeks; (2) IMT plus ‘self-care’ involving education and exercises; and (3) wait list control.

Main outcome measures

Range of motion findings were measured in millimetres by vernier callipers and pain scores were quantified using an 11-point self-reported graded chronic pain scale. Measurements were taken at baseline, 6 weeks post-treatment, and 6 months post-treatment.

Results

The results showed statistically significant differences in resting, opening, and clenching pain and opening range scores (P<0.05) in both treatment groups compared to control at 6 months. No significant differences were observed between the two treatment groups during the course of the trial.

Conclusions

This study suggests that IMT alone or with the addition of self-care may be of some benefit in the management of chronic TMD over the short-medium term. A larger scale study over a longer term (1–2 years) may be of further value.     

Laser Lead Extraction: Is There a Learning Curve?

Laser extraction of device leads offers an attractive alternative to countertraction and electrosurgical dissection sheath, potentially increasing efficacy and reducing complications. Wider adoption of this technology depends on relative ease of use. We report the experience of a new center to define the "learning curve." We performed 76 laser lead extractions in 75 patients (age 63 +/- 17 years, 59 male) from July 2001 to January 2004. Two experienced device implanters who were novice extractors underwent a 2-day site visit to a high volume extraction center for training. Lead extractions were performed in the operating room with immediate surgical backup. The indication for extraction was infection in 39 (systemic in 15), erosion or pain in 11, and lead related or debulking in 25. Complete removal was achieved in 139 of 145 leads (14 ICD, 131 pacemaker). Partial removal (<4 cm retained) was achieved in five leads (4%), and one lead could not be extracted. Complete success was 95% in the first third of patients, 94% in the second third, and 100% in the latter third. Fluoroscopy time fell from 19 +/- 22 minute in the first third of patients to 11 +/- 8 minute in the second third to 8 +/- 4 minute in the latter third (ANOVA P = 0.02). No major complications occurred. Local bleeding required minor left subclavian vein repair in two individuals. Symptomatic venous thrombosis occurred in 3 of the first 11 cases 1-21 days after extraction, but did not occur in the next 64 consecutive patients who received a 1-month anticoagulation regimen (27% vs 0%, P < 0.001). One patient developed venous thrombosis 3 weeks following cessation of warfarin therapy. Practice guidelines reasonably recommend appropriate training prior to independent performance of lead extraction. The current study suggests that experienced device implanters with appropriate operative backup taking a limited, but intensive training program can be safe and effective at lead extraction in a short time, in part a reflection of the improved technology.