Classification of delusions in Alzheimer's disease and their neural correlates

Background: Previous findings on neural correlates of delusion in Alzheimer's disease (AD) have been inconsistent because of methodological issues, such as treating multiple delusions as a single entity. In this retrospective study, we classified AD delusions and investigated their neural correlates by using single‐photon emission computed tomography data. Methods: We selected AD patients with delusions from our consecutive outpatients from 2004 to 2010. In this study, eight types of delusions were evaluated with Neuropsychiatric Inventory and classified by factor analysis. Twenty‐five of the patients also had single‐photon emission computed tomography data, which we used to assess the relationships between cerebral regions of hypoperfusion and hyperperfusion and each classified delusion. The relations were assessed using Statistical Parametric Mapping with normalization to the white matter cerebral blood flow. Results: The delusions were classified into three factors. Factor 1 consisted of a belief that his/her house is not his/her home, phantom boarder symptom, delusion of abandonment, and belief that one's spouse or others are not who they claim to be. Factor 1 was related to hypoperfusion in the right temporal pole and hyperperfusion in the medial frontal and precentral regions. Factor 2 consisted of delusion relating to the television and delusion of persecution. Factor 2 was related to hypoperfusion in the precuneus and hyperperfusion in the insula and thalamus. Factor 3 consisted of delusion of abandonment and delusional jealousy. Factor 3 was related to hypoperfusion in the right inferior temporal and frontal regions and hyperperfusion in the middle frontal gyrus, insula and posterior cingulate gyrus. Delusion of theft was not included in any factors, and it was related to hypoperfusion in the bilateral thalami and left posterior cingulate gyrus and hyperperfusion in the left inferior frontal regions and anterior cingulate gyrus. Conclusions: Delusions in AD were classifiable, and each classified delusion was related to different neural networks.     

Moist-condition Training for Cerebrovascular Anastomosis: A Practical Step after Mastering Basic Manipulations

As cerebrovascular anastomosis is performed in moist conditions that may impede precise manipulations, surgeons must undergo extensive preoperative training. We developed a simple moist-condition training method. It involves placing a free-floating inner platform hosting an artery from a chicken wing in an outer container filled with tap water to just below the specimen. Trainees performed anastomosis under magnification. Training sessions mimicked difficulties encountered during operations such as poor visibility of the lumen and problems handling the sutures. A retrospective comparison of 100 wet- and 100 dry-condition training sessions for end-to-side anastomoses with 8 stitches showed that under moist condition the time required for the entire procedure was significantly longer (17.8 ± 2.1 vs. 15.3 ± 2.1 min, p < 0.01) and the incidence of wrong stitching was greater (0.38 vs. 0%, p = 0.04). In 8 cases after introducing moist-condition training, the time required in superficial temporal artery to middle cerebral artery bypass surgery was significantly shorter than 8 cases before introducing the training (32.3 ± 5.6 min vs. 48.3 ± 15.9 min, p = 0.01). Incidence of wrong stitches was less in cases after introducing moist-condition training (2.7 vs. 7.4%, p = 0.10). Those indicate that moist-condition training is a useful and practical step and a bridge between training for basic manipulations under dry conditions and actual surgery.     

Vagus Nerve Stimulation Therapy: Indications,Programing, and Outcomes

Vagus nerve stimulation (VNS) provides palliation of seizure reduction for patients with medically refractory epilepsy. VNS is indicated for symptomatic localization-related epilepsy with multiple and bilateral independent foci, symptomatic generalized epilepsy with diffuse epileptogenic abnormalities, refractory idiopathic generalized epilepsy, failed intracranial epilepsy surgery, and other several reasons of contraindications to epilepsy surgery. Programing of the parameters is a principal part in VNS. Output current and duty cycle should be adjusted to higher settings particularly when a patient does not respond to the initial setting, since the pivotal randomized trials performed in the United States demonstrated high stimulation made better responses in seizure frequency. These trials revealed that a ≥ 50% seizure reduction occurred in 36.8% of patients at 1 year, in 43.2% at 2 years, and in 42.7% at 3 years in 440 patients. Safety of VNS was also confirmed because side effects including hoarseness, throat discomfort, cough, paresthesia, and headache improved progressively during the period of 3 years. The largest retrospective study with 436 patients demonstrated the mean seizure reduction of 55.8% in nearly 5 years, and also found 75.5% at 10 years in 65 consecutive patients. The intermediate analysis report of the Japan VNS Registry showed that 60% of 164 cases got a ≥ 50% seizure reduction in 12 months. In addition to seizure reduction, VNS has positive effects in mood and improves energy level, memory difficulties, social aspects, and fear of seizures. VNS is an effective and safe option for patients who are not suitable candidates for intracranial epilepsy surgery.     

Antifungal effect of zeolite-incorporated tissue conditioner against Candida albicans growth and/or acid production

summary A new antimicrobial material, Ag-zeolite (Zeomic^°), was combined with a commercial tissue conditioner (GC-Soft Liner (GC); 1–5%) and, through monitoring the pH of the growth medium, examined for effects on the in vitro growth and/or acid production of Candida albicans on protein-free and saliva-coated specimens. The effect of incorporation of this agent on the physical property of the lining material was also examined according to the ISO penetration test. Comparison studies were carried out using GC, Coe Comfort (CC) or undecylenate combined GC (1–5%) specimens. Although the pH changes in the media varied depending upon the materials on which the Candida was grown, reverse sigmoidal pH curves were observed with most samples. As compared with GC, the soft lining materials showed, to some extent, an inhibitory effect on the acid production and/or the growth of C. albicans. These inhibitory effects consisted of a delay in the onset of rapid pH decline, decreases in the rate of pH change and increases in minimum pH. In most cases, the inhibitory effects of test specimens were dose-dependent, and zeolite specimens showed a significantly higher antifungal effect, followed by CC and undecylenate-combined GC; GC showed the least antifungal effect. The inhibitory effects of these materials on fungal growth were decreased by the presence of a saliva-coat, particularly with zeolite specimens and CC. However, four of eight 5%-Zeomic^° specimens still exhibited perfect growth inhibition in the presence of the salivary pellicle. Furthermore, test specimens containing 2–5% Zeomic^° showed a significantly greater effect on the delay in rapid decline of pH, as compared with the other specimens examined. In addition, the significantly higher minimum pH was observed where the yeasts were grown on 4%- and 5%-Zeomic^° specimens. The physical properties of all the test specimens conformed with the ISO standard as examined by penetration test. These results taken together suggest that an antimicrobial zeolite-combined tissue conditioner would be a potential aid in denture plaque control.