Visual histological grading system for the evaluation of in vitro-generated neocartilage

Here we present the development of a visual evaluation system for routine assessment of in vitro-engineered cartilaginous tissue. Neocartilage was produced by culturing human articular chondrocytes in pellet culture systems or in a scaffold-free bioreactor system. All engineered tissues were embedded in paraffin and were sectioned and stained with Safranin O-fast green. The evaluation of each sample was broken into 3 categories (uniformity and intensity of Safranin O stain, distance between cells/amount of matrix produced, and cell morphology), and each category had 4 components with a score ranging from 0 to 3. Three observers evaluated each sample, and the new system was independently tested against an objective computer-based histomorphometry system. Pellets were also assessed biochemically for glycosaminoglycan (GAG) content. Pellet histology scores correlated significantly with GAG contents and were in agreement with the computer-based histomorphometry system. This system allows a valid and rapid assessment of in vitro-generated cartilaginous tissue that has a relevant association with objective parameters indicative of cartilage quality.

Testing visual perception in dementia with Lewy bodies and Alzheimer disease

OBJECTIVE Visuoperceptual deficits are common in dementia with Lewy bodies (DLB) and Alzheimer disease (AD). Testing visuoperception in dementia is complicated by decline in other cognitive domains and extrapyramidal features. To overcome these issues, we developed a computerized test, the Newcastle visuoperception battery (NEVIP), which is independent of motor function and has minimal cognitive load.We aimed to test its utility to identify visuoperceptual deficits in people with dementia. PARTICIPANTS AND MEASUREMENTS We recruited 28 AD and 26 DLB participants with 35 comparison participants of similar age and education. The NEVIP was used to test angle, color, and form discrimination along with motion perception to obtain a composite visuoperception score. RESULTS Those with DLB performed significantly worse than AD participants on the composite visuoperception score (Mann-Whitney U = 142, p = 0.01). Visuoperceptual deficits (defined as 2 SD below the performance of comparisons) were present in 71% of the DLB group and 40% of the AD group. Performance was not significantly correlated with motor impairment, but was significantly related to global cognitive impairment in DLB (rs = -0.689, p <0.001), but not in AD. CONCLUSION Visuoperceptual deficits can be detected in both DLB and AD participants using the NEVIP, with the DLB group performing significantly worse than AD. Visuoperception scores obtained by the NEVIP are independent of participant motor deficits and participants are able to comprehend and perform the tasks.

Characteristics of visual hallucinations in Parkinson disease dementia and dementia with Lewy bodies

OBJECTIVE Parkinson disease dementia (PDD) and dementia with Lewy bodies (DLB) have overlapping clinical and pathologic features. Recurrent visual hallucinations (RVH) are common in both disorders. The authors have compared details of hallucination characteristics and associated neuropsychiatric features in DLB and PDD. METHODS This is a descriptive, cross-sectional study using the Institute of Psychiatry Visual Hallucinations Interview (IP-VHI) to explore self-reported frequency, duration, and phenomenology of RVH in PDD and DLB. The caregivers' ratings of hallucinations and other neuropsychiatric features were elicited with the Neuropsychiatric Inventory (NPI). RESULTS Fifty-six patients (35 PDD; 21 DLB) with RVH were assessed. Hallucination characteristics were similar in both disorders. Simple hallucinations were rare. Most patients experienced complex hallucinations daily, normally lasting minutes. They commonly saw people or animals and the experiences were usually perceived as unpleasant. NPI anxiety scores were higher in PDD. Neuropsychiatric symptoms coexisting with hallucinations were apathy, sleep disturbance, and anxiety. CONCLUSIONS Patients with mild to moderate dementia can provide detailed information about their hallucinations. Characteristics of RVH were similar in PDD and DLB, and phenomenology suggests the involvement of dorsal and ventral visual pathways in their generation. The coexistence of RVH with anxiety, apathy, and sleep disturbance is likely to impair patients' quality of life and may have treatment implications.

Visual perception in Parkinson disease dementia and dementia with Lewy bodies

OBJECTIVE To quantify visual discrimination, space-motion, and object-form perception in patients with Parkinson disease dementia (PDD), dementia with Lewy bodies (DLB), and Alzheimer disease (AD). METHODS The authors used a cross-sectional study to compare three demented groups matched for overall dementia severity (PDD: n = 24; DLB: n = 20; AD: n = 23) and two age-, sex-, and education-matched control groups (PD: n = 24, normal controls [NC]: n = 25). RESULTS Visual perception was globally more impaired in PDD than in nondemented controls (NC, PD), but was not different from DLB. Compared to AD, PDD patients tended to perform worse in all perceptual scores. Visual perception of patients with PDD/DLB and visual hallucinations was significantly worse than in patients without hallucinations. CONCLUSIONS Parkinson disease dementia (PDD) is associated with profound visuoperceptual impairments similar to dementia with Lewy bodies (DLB) but different from Alzheimer disease. These findings are consistent with previous neuroimaging studies reporting hypoactivity in cortical areas involved in visual processing in PDD and DLB.