Evaluation of cognitive deficits in patients infected with COVID-19.

OBJECTIVE: COVID-19 infection can cause impairments in many cognitive areas. The aim of the present study was to evaluate the cognitive functions of patients who had been infected with COVID-19. PATIENTS AND METHODS: The demographic and infection-related characteristics of patients who had been infected with COVID-19 were determined. Their cranial magnetic resonance imaging (MRI) and electroencephalography (EEG) findings were recorded. The Mini-Mental State Evaluation (MMSE), clock drawing test, forward and backward digit span tests, visual memory test, and Frontal Assessment Battery were applied to the patients. Finger agnosia and ideomotor apraxia were also determined. RESULTS: The study included 176 patients [100 female (56.8%), 76 male (43.2%), mean age 66.09±13.96 years]. About half of the patients were hospitalized for symptoms of COVID-19 infection (n=82, 46.6%). One third of these patients required intensive care (n=26, 14.8%). While 50 (45.9%) of the 109 patients diagnosed with dementia before infection were hospitalized, 32 (47.8%) of the 67 patients without a diagnosis of dementia required hospitalization (p=0.46). The most common neurological finding during COVID-19 infection was insomnia (n=36, 20.5%). The MMSE and visual memory test scores of the patients who were hospitalized for severe respiratory distress were lower than those whose treatment at home was completed (respectively 17.92±7.69/20.59±7.01, p=0.02; 2.53 ±1.73/3.69±2.80, p=0.01). The patients with moderate to severe cognitive impairment had significantly higher CRP levels at admission than the others (37.52±43.09/20.93±31.74, p=0.01, respectively). CONCLUSIONS: Cognitive damage in COVID-19 infection may be caused by ACE receptor density in the pial, hippocampal, and amygdala areas. In addition, the reason why people with severe dementia have a milder infection might be explained by the atrophy in these areas.

Measuring the apparent diffusion coefficient in primary rectal tumors: is there a benefit in performing histogram analyses?

PURPOSE: The apparent diffusion coefficient (ADC) is a potential prognostic imaging marker in rectal cancer. Typically, mean ADC values are used, derived from precise manual whole-volume tumor delineations by experts. The aim was first to explore whether non-precise circular delineation combined with histogram analysis can be a less cumbersome alternative to acquire similar ADC measurements and second to explore whether histogram analyses provide additional prognostic information. METHODS: Thirty-seven patients who underwent a primary staging MRI including diffusion-weighted imaging (DWI; b0, 25, 50, 100, 500, 1000; 1.5 T) were included. Volumes-of-interest (VOIs) were drawn on b1000-DWI: (a) precise delineation, manually tracing tumor boundaries (2 expert readers), and (b) non-precise delineation, drawing circular VOIs with a wide margin around the tumor (2 non-experts). Mean ADC and histogram metrics (mean, min, max, median, SD, skewness, kurtosis, 5th-95th percentiles) were derived from the VOIs and delineation time was recorded. Measurements were compared between the two methods and correlated with prognostic outcome parameters. RESULTS: Median delineation time reduced from 47-165 s (precise) to 21-43 s (non-precise). The 45th percentile of the non-precise delineation showed the best correlation with the mean ADC from the precise delineation as the reference standard (ICC 0.71-0.75). None of the mean ADC or histogram parameters showed significant prognostic value; only the total tumor volume (VOI) was significantly larger in patients with positive clinical N stage and mesorectal fascia involvement. CONCLUSION: When performing non-precise tumor delineation, histogram analysis (in specific 45th ADC percentile) may be used as an alternative to obtain similar ADC values as with precise whole tumor delineation. Histogram analyses are not beneficial to obtain additional prognostic information.

CLINICAL EFFECT OF A MUTATION (p.Glu322Asp, c.966 G>T) IN PANK2 GENE IN A FAMILY WITH ATYPICAL PANTOTHENATE KINASE-ASSOCIATED NEURODEGENERATION.

Pantothenate-kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder caused by mutations in the pantothenate kinase 2 (PANK2) gene. Many different mutations in the PANK2 gene have been detected in association with PKAN. A 20 year old female patient who had been suffering from progressive gait disorder for 1 year was found to have the 'eye-of-the-tiger sign' from the brain magnetic resonance imaging (MRI). The same brain imaging findings were shown in the father and brother of the patient, whose parents arranged a consanguineous marriage. We found c.966 G>T (p.Glu322Asp) mutation in the PANK2 gene mutation analysis in the individuals from the brain imaging findings. Although individuals in this family who had a homozygous mutation in PANK2 gene analyses had the 'eye-of-the-tiger' sign and atypical disease, they were noted to have differing clinical findings.

Exonic versus intronic SNPs: contrasting roles in revealing the population genetic differentiation of a widespread bird species.

Recent years have seen considerable progress in applying single nucleotide polymorphisms (SNPs) to population genetics studies. However, relatively few have attempted to use them to study the genetic differentiation of wild bird populations and none have examined possible differences of exonic and intronic SNPs in these studies. Here, using 144 SNPs, we examined population genetic differentiation in the saker falcon (Falco cherrug) across Eurasia. The position of each SNP was verified using the recently sequenced saker genome with 108 SNPs positioned within the introns of 10 fragments and 36 SNPs in the exons of six genes, comprising MHC, MC1R and four others. In contrast to intronic SNPs, both Bayesian clustering and principal component analyses using exonic SNPs consistently revealed two genetic clusters, within which the least admixed individuals were found in Europe/central Asia and Qinghai (China), respectively. Pairwise D analysis for exonic SNPs showed that the two populations were significantly differentiated and between the two clusters the frequencies of five SNP markers were inferred to be influenced by selection. Central Eurasian populations clustered in as intermediate between the two main groups, consistent with their geographic position. But the westernmost populations of central Europe showed evidence of demographic isolation. Our work highlights the importance of functional exonic SNPs for studying population genetic pattern in a widespread avian species.