Development and characterisation of an irradiation device for biomedical studies covering the solar spectrum with individual regulated spectral bands

To understand the importance of terrestrial solar exposure on human skin, not only individual spectral components need to be considered in biomedical studies, but also the relevance of the combined action profile of the complete solar spectrum (cSS) must be established. We therefore developed a novel irradiation device that combines the emission of four individual lamps (UVB, UVA, VIS and nIR) to achieve exposure from 280 to 1400 nm with individual controllable lamps. The integrated irradiance of each spectral band is similar to the solar spectrum. The lamps can be utilised individually or in any desired combination. Here we present the design, realisation, and validation of this irradiation device as well as biological results on cellular metabolism (MTT assay), cell cycle alterations, and clonogenic growth in HaCaT cells after exposures to the individual spectral bands as well as their simultaneous combinations. Thereby, we demonstrate that UVB combined with UVA is the main determinant for the metabolic activity within cSS. Also, UVB-dependent effects dominate cell cycle regulation in cSS, whilst UVA and nIR have little influence. Lastly, also clonogenic growth is dominated by the UVB action profile in cSS, despite nIR showing modulatory activity when applied in combination with UVB. Together, this highlights the regulatory influence of the different spectral bands on the three biological endpoints and demonstrates their modulation when being part of the complete solar spectrum.

Unsupervised Performance of the CogState Brief Battery in the Brain Health Registry: Implications for Detecting Cognitive Decline

INTRODUCTION:

The feasibility and validity of unsupervised, longitudinal brief computerized cognitive batteries is unknown.

METHODS:

Participants aged 56–90 (N = 19476) from the Brain Health Registry (BHR) completed the CogState Brief Battery (CBB) at 6-month intervals over a period of 5 years. We used linear mixed-effects models to assess whether cross-sectional and longitudinal performance on CBB within BHR was associated with demographic and cognitive characteristics. We also defined a group of CBB decliners based on subject-specific slopes and estimated associations between decliner status and participant characteristics.

RESULTS:

We found weak associations between longitudinal change in CBB and participant characteristics. Cross-sectional CBB scores were significantly associated with participant characteristics such as age, gender, ethnicity, self-reported disease status, and memory concern. CBB decliners were more likely to self-report mild cognitive impairment (MCI) and memory concerns.

DISCUSSION:

Cross-sectional, remote CBB shows evidence of construct validity, but our results suggest that longitudinal assessment may not provide additional value for identifying those at risk for and with cognitive impairment.

Normative Data that Does Not Exclude Participants with Mild Cognitive Impairment Results in Lower Than Expected Memory Impairment Rates, Particularly in Females

Objective

Mayo’s Older Adult Normative Studies (MOANS) have served as an important resource for clinicians for three decades. Data collection was completed prior to the development and widespread use of Mild Cognitive Impairment (MCI) as a construct. Therefore, a portion of individuals included in the MOANS normative studies likely had undetected cognitive impairment.

Method

The Mayo Clinic Study of Aging (MCSA) is a population-based study of cognitive aging among Olmsted County, Minnesota, residents that began in October 2004. We applied age-adjusted MOANS norms (Ivnik et al., 1992) for the Auditory Verbal Learning Test (AVLT) long delay recall to cognitively unimpaired participants age 56 or older in the MCSA (N = 3,603). We used 1-sample tests of proportions comparing observed impairment rates to impairment rates expected based on a normal distribution of performance.

Results

Results showed that a significantly lower than expected number of participants demonstrated impaired delayed recall based on MOANS norms (all p’s < .001). Using a lenient cut-off (< -1 SD), only 7.3% of participants demonstrated impaired performance (vs. 15.9% expected), and this was more pronounced for females (3.5% impaired) relative to males (11.1% impaired). Further, only 0.6% of participants demonstrated impaired performance at a cut-off of < -2 SD, and no participants aged 80-91 reached this cut-off (2.3% expected).

Conclusions

Results suggest that the sensitivity of the original MOANS norms is lowered by likely inclusion of individuals with MCI, particularly in females. Updated normative data for the AVLT that exclude individuals with MCI and adjust for sex are needed.

Is Early Treatment with a Cervical Pessary an Option in Patients with a History of Surgical Conisation and a Short Cervix?

Objective: Patients with a history of one or more conizations have an increased risk of spontaneous preterm birth (SPTB). The aim of this study was to investigate the outcome of pregnancies in patients with a history of conization and early treatment with a cervical pessary. Methods: In this pilot observational study we included 21 patients and evaluated the obstetric history, the interval between pessary placement and delivery, gestational age at delivery, the neonatal outcome and the number of days of maternal and neonatal admission. Results: Among the study group of 21 patients, 20 patients had a singleton and one had a dichorionic/diamniotic twin pregnancy. At insertion, the mean gestational age was 17 + 2 (10 + 5-24 + 0) weeks and the mean cervical length was 19 (4-36) mm. Six patients presented with funneling at insertion with a mean funneling width of 19.7 (10-38) mm and funneling length of 19.9 (10-37) mm. Five patients had already lost at least one child due to early spontaneous preterm birth and another five had at least one previous abortion, who have now delivered beyond 34 weeks. The mean gestational age at delivery was 38 (31 + 1-41 + 0) gestational weeks and the mean interval between insertion and delivery was 145 (87-182) days. Conclusion: Our findings suggest a beneficial effect of an early pessary placement for patients at high-risk for preterm birth due to conization.