Subjective Cognitive Complaints: Comparing the Relation between Self-Reported Versus Informant-Reported Subjective Cognitive Complaints and Cognitive Performances in Cognitively Unimpaired, Mild Cognitive Impairment and Populations with Dementia.

BACKGROUND: Subjective cognitive decline is proposed to be associated with future mild cognitive impairment and dementia. A better understanding of the roles of self-reported and informant-reported subjective cognitive complaints can provide a more delicate picture in dementia recognition and early diagnosis. OBJECTIVES: To evaluate the accuracy of self-reported and informant-reported subjective cognitive complaints and the relation of subjective cognitive complaints and neuropsychological function in cognitively unimpaired, mild cognitive impairment and populations with dementia. DESIGN: We conducted a cross-sectional survey and evaluate the relations between subjective cognitive complaint scores and cognitive function in the different diagnostic groups. SETTING: We recruited individuals diagnosed with cognitively unimpaired or mild cognitive impairment or dementia with Alzheimer's clinical syndrome from a memory clinic in a tertiary medical center in Taiwan. PARTICIPANTS: Participants, age greater than 50 years old, were enrolled in this study. Participants' informants were also enrolled for the cognitive questionnaire assessment. MEASUREMENTS: Participants' and informants' subjective cognitive complaint scores were collected based on a 12-item questionnaire. Neuropsychological assessments of global cognitive function, memory, language, executive function, visuospatial function and calculation were performed. The relations between subjective cognitive complaint scores and cognitive function in the different diagnostic groups were assessed by linear regression model. RESULTS: There were 1536 individuals and 1028 informants enrolled in this study. Self-reported subjective cognitive complaint scores from early and late mild cognitive impairment and dementia with Alzheimer's clinical syndrome participants showed no significant differences, but informants' subjective cognitive complaint scores showed a significant increase. Informant-reported subjective cognitive complaint scores related to neuropsychological tests in population with dementia. Neither self-reported nor informant-reported subjective cognitive complaint scores related to neuropsychological tests in cognitively unimpaired and mild cognitive impairment populations. CONCLUSIONS: Self-reported subjective cognitive complaints alone may not be sufficient to demonstrate clinical significance in different stages of cognitive impairment. Incorporating informant-reported subjective cognitive complaints, along with considering individual's anxiety and depressive status, are crucial in assessing cognitive statuses in clinical practice.

Predictive Utility of Plasma Amyloid and Tau for Cognitive Decline in Cognitively Normal Adults.

BACKGROUND: Alzheimer's disease (AD) is the most common neurodegenerative disease affecting mostly elderly adults. Recent diagnostic criteria for AD recommend the use of imaging and/or cerebrospinal fluid (CSF) biomarkers together with clinical presentation for a more persuasive diagnosis. The invasiveness and expense of such examinations have led to the search for blood-based biomarkers. The plasma levels of amyloid-ß (Aß) protein and tau peptides have been found to correlate with CSF levels and imaging findings in patients with AD. This study was conducted to explore the predictive utility of plasma Aß1-42 and total tau (t-tau) levels for cognitive decline in healthy adults. METHODS: In this prospective longitudinal study, we enrolled adults aged ≥ 50 years with normal cognition at Taipei Veterans General Hospital from November 2016 to April 2019. Blood samples were collected on recruitment, and plasma Aß1-42 and t-tau levels were quantified through immunomagnetic reduction. Thorough neurophysiological assessment was performed at baseline and at the annual follow-up visit. The participants were divided into two groups according to cognitive decline. The predictive utility of Aß1-42 and t-tau levels was evaluated by receiver operating characteristic curve analysis. RESULTS: Of 60 participants recruited, seven participants progressed to mild cognitive impairment and 53 retained normal cognition on follow-up (average 1.07 ± 0.2 years). The baseline levels of plasma biomarkers (Aß1-42, t-tau, and Aß1-42 × t-tau) were significantly higher in the progressive than in the stable group (p = 0.005, p = 0.007, and p = 0.005, respectively). Higher plasma biomarker levels (Aß1-42 ≥ 16.96 pg/ml and Aß1-42 × t-tau ≥ 382 pg2/ml2) predicted more cognitive decline on annual follow-up visits. CONCLUSION: Plasma Aß1-42 and t-tau levels have predictive utility for cognitive decline, even in subjects with normal cognition. Higher baseline plasma Aß1-42 and t-tau levels may indicate a higher risk of cognitive decline in cognitively normal adults.

[A short half-life of cccDNA offer or ignite hope for hepatitis B cure under nucleos(t)ide analogues treatment].

Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is the template for HBV replication. Currently, there is a lack of therapeutic drugs that directly target cccDNA. Therefore, blocking cccDNA supplements as fast as possible and reducing the existing cccDNA is the key to achieving a complete cure of chronic hepatitis B. Previous studies have suggested that cccDNA had a long half-life, but a recent study showed that it only took a few months to update cycle of cccDNA pool, and its number was much less than previously predicted. In the future, with the advent of new antiviral drugs that can completely inhibit HBV replication, it is expected that the cccDNA pool will be completely cleared due to its supplement complete blockade, so as to achieve virological cure of chronic hepatitis B.

[Exploring the mechanism of liver enzyme abnormalities in patients with novel coronavirus-infected pneumonia].

Objective: To explore and analyze the possible mechanism of liver injury in patients with coronavirus disease 2019 (novel coronavirus pneumonia, NCP). Methods: The correlation between ALT, AST and other liver enzyme changes condition and NCP patients' disease status reported in the literature was comprehensively analyzed. ACE2 expression in liver tissue for novel coronavirus was analyzed based on single cell sequencing (GSE115469) data. RNA-Seq method was used to analyze Ace2 expression and transcription factors related to its expression in liver tissues at various time-points after hepatectomy in mouse model of acute liver injury with partial hepatectomy. t-test or Spearman rank correlation analysis was used for statistical analysis. Results: ALT and AST were abnormally elevated in some patients with novel coronavirus infection, and the rate and extent of ALT and AST elevation in severe NCP patients were higher than those in non-severe patients. Liver tissue results of single cell sequencing and immunohistochemistry showed that ACE2 was only expressed in bile duct epithelial cells of normal liver tissues, and very low in hepatocytes. In a mouse model of acute liver injury with partial hepatectomy, Ace2 expression was down-regulated on the first day, but it was elevated up to twice of the normal level on the third day, and returned to normal level on seventh day when the liver recovered and hepatocyte proliferation stopped. Whether this phenomenon suggests that the bile duct epithelial cells with positive expression of Ace2 participate in the process of liver regeneration after partial hepatectomy deserves further study. In RNA-Seq data, 77 transcription factors were positively correlated with the expression of Ace2 (r > 0.2, FDR < 0.05), which were mainly enriched in the development, differentiation, morphogenesis and cell proliferation of glandular epithelial cells. Conclusion: We assumed that in addition to the over activated inflammatory response in patients with NCP, the up-regulation of ACE2 expression in liver tissue caused by compensatory proliferation of hepatocytes derived from bile duct epithelial cells may also be the possible mechanism of liver tissue injury caused by 2019 novel coronavirus infection.

Papillomavirus capsid protein expression level depends on the match between codon usage and tRNA availability.

Translation of mRNA encoding the L1 and L2 capsid proteins of papillomavirus (PV) is restricted in vivo to differentiated epithelial cells, although transcription of the L1 and L2 late genes occurs more widely. The codon composition of PV late genes is quite different from that of most mammalian genes. To test the possibility that PV late gene codon composition determines the efficiency of PV late gene expression in some cell types, synthetic bovine papillomavirus type 1 (BPV1) late genes were constructed with codon composition modified to resemble the typical mammalian gene. Expression of these genes from a strong promoter in Cos-1 cells was compared with expression of wild-type BPV1 late genes from the same promoter. Both unmodified and modified PV late genes were transcribed in Cos-1 cells, but only the codon-modified genes were translated. In vitro translation of wild-type but not synthetic BPV1 L1 mRNA was markedly enhanced by addition of aminoacyl-tRNAs. Codon composition thus limits BPV1 late gene translation in Cos-1 cells, and this limitation can be overcome by modification of the codon composition of the genes or by provision of excess tRNA. Replacement of codons in the green fluorescent protein (gfp) gene with those frequently used in PV late genes did not alter gfp transcription in Cos-1 cells but almost abolished translation, supporting the hypothesis that the observed differences in efficiency of translation of modified and unmodified PV capsid genes were related to codon usage rather than mRNA structure. As tRNA populations vary within and between tissues in the same eukaryotic organism, we speculate that matching of tRNA availability to codon usage may be one determinant of the restriction of expression of PV late genes to differentiated epithelium.

Type specific and genotype cross reactive B epitopes of the L1 protein of HPV16 defined by a panel of monoclonal antibodies.

Mouse monoclonal antibodies (mAbs) were raised against the major capsid protein, L1, of human papillomavirus type 16 (HPV16), produced in Escherichia coli with the expression plasmid pTrcL1. Epitope specificity could be assigned to 11 of these 12 antibodies using a series of linear peptides and fusion proteins from HPV16. One mAb (MC53) recognized a novel linear epitope that appears to be unique to the HPV16 genotype. A further 11 mAbs were characterized as recognizing novel and previously defined linear and conformational epitopes shared among more than one HPV genotype. The apparently genotype specific mAb could be useful for the development of diagnostic tests for vegetative virus infection in clinical specimens.

Epithelial cells display separate receptors for papillomavirus VLPs and for soluble L1 capsid protein.

We examined the distribution of putative receptors for papillomavirus (PV) capsid proteins on various cell types, using either Hexahis HPV6b L1 fusion protein or synthetic HPV6b virus-like particles (VLPs). Specific, saturable binding of VLPs to CV-1 cells was demonstrated using 35S-labeled VLPs, with an average receptor number of 1 x 10(4)/cell and a binding affinity constant (Ka) of 4 x 10(7) M. VLP binding was quantitated by flow cytometry using a monoclonal antibody to the L1 capsid protein. Intense staining of epithelial and mesenchymal cells was observed. Some immature bone marrow-derived cells bound VLPs weakly, while the majority of B lymphoma cells demonstrated no binding. Binding to 12 of 16 VLP receptor positive cell lines was abolished by trypsin pretreatment of cells. Removal of cellular sialic acid or O-linked oligosaccharides separately did not affect VLP binding, which was enhanced about 25% when cells were pretreated with both neuraminidase and O-glycosidase. Culture of cells with sufficient tunicamycin to inhibit Concanavalin A binding did not diminish the binding of VLPs. Denatured L1 protein, either from VLPs or expressed from Escherichia coli as a Hexahis fusion protein, bound to a trypsin-resistant structure on a range of cell types and did not block the binding of VLPs to cells. Dual-fluorescence assay with a Burkitt lymphoma line BL72 demonstrated that Hexahis L1 protein and VLPs bind to separate cell surface molecules on BL72 cells. We conclude that the first binding of PV virus to cells is via a widely distributed membrane protein receptor(s) and that subsequent processing of particles may involve other non-trypsin-sensitive structure(s) also displayed on the cell membrane.