Safety and biodegradability of a synthetic dural sealant patch (Liqoseal) in a porcine cranial model

BackgroundLiqoseal consists of a watertight layer of poly(ester)ether urethane and an adhesive layer containing polyethylene glycol‐N‐hydroxysuccinimide (PEG‐NHS). It is designed to prevent cerebrospinal fluid (CSF) leakage after intradural surgery. This study assessed the safety and biodegradability of Liqoseal in a porcine craniotomy model.MethodsIn 32 pigs a craniotomy plus durotomy was performed. In 15 pigs Liqoseal was implanted, in 11 control pigs no sealant was implanted and in 6 control pigs a control dural sealant (Duraseal or Tachosil) was implanted. The safety of Liqoseal was evaluated by clinical, MRI and histological assessment. The degradation of Liqoseal was histologically estimated.ResultsLiqoseal, 2 mm thick before application, did not swell and significantly was at maximum mean thickness of 2.14 (±0.37) mm at one month. The foreign body reaction induced by Liqoseal, Duraseal and Tachosil were comparable. Liqoseal showed no adherence to the arachnoid layer and was completely resorbed between 6 and 12 months postoperatively. In one animal with Liqoseal, an epidural fluid collection containing CSF could not be excluded.ConclusionLiqoseal seems to be safe for intracranial use and is biodegradable. The safety and performance in humans needs to be further assessed in clinical trials.     

“STA-MCA bypass with encephalo-duro-myo-synangiosis combined with bifrontal encephalo-duro-periosteal-synangiosis” as a one-staged revascularization strategy for pediatric moyamoya vasculopathy

Purpose

Moyamoya vasculopathy progressively compromises cerebral blood flow resulting in chronic hypoperfusion. The middle cerebral artery (MCA) territory and the bifrontal areas are the regions most frequently affected. Although most techniques aim to only revascularize the MCA territory, augmentation of blood flow of the bifrontal areas is of importance in the pediatric moyamoya population since these regions play an important role in cognition, intellectual development, and in lower extremity and sphincter function. We recently described a one-staged surgical procedure combining revascularization of three regions, the MCA territory unilaterally and the frontal areas bilaterally. The purpose of this article is to report our surgical experience in eight children and to emphasize the rational for bifrontal revascularization.

Methods

We report a case series consisting of eight children where the following surgical strategy was applied: (1) a direct superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass with encephalo-duro-myo-synangiosis (EDMS) for unilateral MCA revascularization; in combination with (2) a bifrontal encephalo-duro-periosteal-synangiosis (EDPS) for bifrontal revascularization. Patients’ characteristics and 30-day follow-up data are reported.

Results

The patient group consisted of six girls and two boys (mean age 10.0, range 4.2–17.5 years): six children presented with moyamoya disease, two with moyamoya syndrome. We performed a one-staged revascularization of one MCA territory and both frontal areas in all patients. No significant complications occurred. Two patients experienced postoperative focal seizures, successfully treated with anti-epileptic medication.

Conclusions

The single-staged STA-MCA bypass with EDMS combined with bifrontal EDPS allowed revascularization of three regions (the MCA territory unilaterally and the frontal areas bilaterally) and may serve as an alternative and safe treatment option for pediatric moyamoya patients.

     

Gender-selective neural populations: evidence from event-related fMRI repetition suppression

Accurate recognition of gender in another individual is integral to successful human social interaction and to mate selection. When we encounter another person, we are effortlessly able to identify their gender, most often through the information conveyed by their facial features. Faces comprise the most abundantly encountered cue used to classify human gender. Considering the importance of facial information in gender perception, relatively little is known about the mechanisms involved in perceiving gender through human facial cues. We used an event-related fMRI repetition suppression paradigm to explore the neural circuitry underlying gender perception from facial information. Participants viewed brief consecutive images consisting of either gender-same face pairings (two male faces or two female faces) or images of gender-different face pairings (a male face preceded or followed by a female face), while attending to facial attractiveness in both conditions. Using a region-of-interest approach, we found repetition suppression on gender-same trials within the left ventral temporal fusiform gyrus and in the right collateral sulcus. Whole-brain voxel-wise analyses revealed selectivity for face gender again in the right collateral sulcus, in addition to the left cuneus and the right lateral occipital gyrus. Our results indicate that in addition to the face-selective FFA, cortical areas that are not traditionally considered to be “face-selective” are involved in the perception of gender-based facial cues.     

Invasive extramammary Paget’s disease and the risk for secondary tumours in Europe

The aim of this study was to determine the incidence and survival of Extramammary Paget’s disease (EMPD) and to describe the possible increased risk of tumours after EMPD.     

Plasma myeloperoxidase is inversely associated with endothelium-dependent vasodilation in elderly subjects with abnormal glucose metabolism

Myeloperoxidase (MPO), a biomarker related to inflammation, oxidative stress, and nitric oxide scavenging, has been shown to impair endothelium-dependent vasodilation. Because elevated hydrogen peroxide concentrations in diabetic vessels may enhance MPO activity, we hypothesized that a stronger association of MPO with flow-mediated dilation (FMD) may be found in subjects with abnormal glucose metabolism. Myeloperoxidase concentrations were measured in EDTA plasma samples from participants of a population-based cohort study, including 230 subjects with normal glucose metabolism and 386 with abnormal glucose metabolism. Vascular function was expressed as FMD and nitroglycerin-mediated dilation of the brachial artery. In subjects with abnormal glucose metabolism, MPO was negatively associated with FMD (−20.9 [95% confidence interval {CI}, −41.7 to −0.2] -μm change in FMD per SD increment of MPO). This association remained significant after adjustment for nitroglycerin-mediated dilation (−31.1 [95% CI, −50.0 to −12.3]) and was not attenuated after further adjustment for established risk factors. In subjects with normal glucose metabolism, MPO was not significantly associated with FMD (2.0 [95% CI, −16.0 to 20.0]). In conclusion, in subjects with abnormal glucose metabolism, plasma levels of MPO are inversely associated with endothelium-dependent vasodilation, possibly reflecting enhancement of MPO activity by vascular oxidative stress.