Differential diagnosis and prospective grading of COVID-19 at the early stage with simple hematological and biochemical variables.

We evaluated simple laboratory variables to discriminate COVID-19 from bacterial pneumonia or influenza and for the prospective grading of COVID-19. Multivariate logistic regression and receiver operating characteristic curve were used to estimate the diagnostic performance of the significant discriminating variables. A comparative analysis was performed with different severity. The leukocytosis (P = 0.017) and eosinopenia (P = 0.001) were discriminating variables between COVID-19 and bacterial pneumonia with area under the curve (AUC) of 0.778 and 0.825. Monocytosis (P = 0.003), the decreased lymphocyte-to-monocyte ratio (P < 0.001), and the increased neutrophil-to-lymphocyte ratio (NLR) (P = 0.028) were predictive of influenza with AUC of 0.723, 0.895, and 0.783, respectively. Serum amyloid protein, lactate dehydrogenase, CD3+ cells, and the fibrinogen degradation products had a good correlation with the severity of COVID-19 graded by age (≥50) and NLR (≥3.13). Simple laboratory variables are helpful for rapid diagnosis on admission and hierarchical management of COVID-19 patients.

New fluid biomarkers tracking non-amyloid-ß and non-tau pathology in Alzheimer's disease.

Cerebrospinal fluid (CSF) biomarkers based on the core pathological proteins associated with Alzheimer's disease (AD), i.e., amyloid-ß (Aß) and tau protein, are widely regarded as useful diagnostic biomarkers. However, a lack of biomarkers for monitoring the treatment response and indexing clinical severity has proven to be problematic in drug trials targeting Aß. Therefore, new biomarkers are needed to track non-Aß and non-tau pathology. Many proteins involved in the pathophysiological progression of AD have shown promise as new biomarkers. Neurodegeneration- and synapse-related biomarkers in CSF (e.g., neurofilament light polypeptide [NFL], neurogranin, and visinin-like protein 1) and blood (e.g., NFL) aid prediction of AD progress, as well as early diagnosis. Neuroinflammation, lipid dysmetabolism, and impaired protein clearance are considered important components of AD pathophysiology. Inflammation-related proteins in the CSF, such as progranulin, intercellular adhesion molecule 1, and chitinase-3-like protein 1 (YKL-40), are useful for the early detection of AD and can represent clinical severity. Several lipid metabolism-associated biomarkers and protein clearance-linked markers have also been suggested as candidate AD biomarkers. Combinations of subsets of new biomarkers enhance their utility in terms of broadly characterizing AD-associated pathological changes, thereby facilitating precise selection of susceptible patients and comprehensive monitoring of the treatment response. This approach could facilitate the development of effective treatments for AD.

Total Aß42/Aß40 ratio in plasma predicts amyloid-PET status, independent of clinical AD diagnosis.

OBJECTIVE: To explore whether the plasma total ß-amyloid (Aß) Aß42/Aß40 ratio is a reliable predictor of the amyloid-PET status by exploring the association between these 2 variables in a subset of the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging cohort. METHODS: Taking plasma samples at 3 separate time points, month 18 (n = 176), month 36 (n = 169), and month 54 (n = 135), we assessed the total Aß42/Aß40 ratio in plasma (TP42/40) with regard to neocortical Aß burden via PET standardized uptake value ratio (SUVR) and investigated both association with Aß-PET status and correlation (and agreement) with SUVR. RESULTS: The TP42/40 plasma ratio was significantly reduced in amyloid-PET-positive participants at all time points (p < 0.0001). Adjusting for covariates age, gender, APOE ε4 allele status, and clinical classification clearly affects the significance, with p values reduced and only comparisons at 54 months retaining significance (p = 0.006). Correlations with SUVR were similar across each time point, with Spearman ρ reaching -0.64 (p < 0.0001). Area under the curve values were highly reproducible over time points, with values ranging from 0.880 at 36 months to 0.913 at 54 months. In assessments of the healthy control group only, the same relationships were found. CONCLUSIONS: The current study demonstrates reproducibility of the plasma assay to discriminate between amyloid-PET positive and negative over 3 time points, which can help to substantially reducing the screening rate of failure for clinical trials targeting preclinical or prodromal disease. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that plasma total Aß42/Aß40 ratio is associated with neocortical amyloid burden as measured by PET SUVR.

Effects of folic acid supplementation on cognitive function and Aß-related biomarkers in mild cognitive impairment: a randomized controlled trial.

PURPOSE: Observational studies have frequently reported that low blood folate concentrations are associated with poor cognitive performance. Our previous studies have shown the potential beneficial effect on the metabolite levels of methionine cycle and peripheral blood inflammatory cytokines from 6- and 12-month folic acid supplementation on cognitive function in mild cognitive impairment (MCI). This study aims to continue exploring the effect of 24-month folic acid supplementation on cognitive function and pathological mechanism in MCI. METHODS: 180 individuals with MCI were identified and randomly divided into intervention (folic acid 400 µg/day, n = 90) and convention (n = 90) groups. Cognitive function (WAIS-RC) and blood Aß-related biomarkers were measured at baseline and at 6, 12, 18, and 24 months. Data were analyzed using generalized estimating equation. This trial has been registered with Trial Number: ChiCTR-TRC-13003227. RESULTS: During the follow-up, scores of full scale IQ, verbal IQ, and subdomains of Information and Digit Span were significantly higher in the intervention group than those in the convention group (P < 0.05). In the intervention group, blood homocysteine, S-adenosylhomocysteine (SAH), Aß-42, and the expression of APP-mRNA were decreased (P < 0.05), while S-adenosylmethionine (SAM), SAM/SAH ratio, and the expression of DNA methyltransferase mRNA were increased (P < 0.05). CONCLUSION: Folic acid supplementation appears to improve cognitive function and reduce blood levels of Aß-related biomarkers in MCI. Larger-scale double-blind placebo-controlled randomized trials of longer duration are needed.

Innate phagocytosis by peripheral blood monocytes is altered in Alzheimer's disease.

Sporadic Alzheimer's disease (AD) is characterised by the deposition and accumulation of specific protein aggregates. Failure of clearance could underlie this process, and recent genetic association studies point towards involvement of the phagocytosis and autophagy pathways. We developed a real-time tri-color flow cytometry method to quantitate the phagocytic function of human peripheral blood monocyte subsets including non-classic CD14(dim)CD16(+), intermediate CD14(+)CD16(+) and classic CD14(+)CD16(-) monocytes. Using this method, we have measured the phagocytic ability of fresh monocytes in a study of preclinical, prodromal and clinical AD, matched with cognitively normal healthy control subjects. Basal levels of phagocytosis in all three subsets of monocytes were similar between healthy controls and AD patients, while a significant increase of basal phagocytosis was found in subjects with high Aß-amyloid burden as assessed by PET scans. Pre-treating cells with Copaxone (CPX, to stimulate phagocytosis) or ATP (an inhibitor of P2X7-mediated phagocytosis) showed a differential response depending on clinical or Aß-burden status, indicating a relative functional deficit. Overall the results are consistent with a perturbation of basal and stimulated innate phagocytosis in sporadic AD.

Outcomes of light-chain amyloidosis patients treated with first-line bortezomib: a collaborative retrospective multicenter assessment.

Light-chain amyloidosis (AL) is associated with low survival rates, particularly in patients with cardiac involvement. We evaluated the outcome of 73 consecutive, non-selected 'real-world' AL patients, treated with first-line bortezomib-based induction, focusing on the benefit of concurrent administration of alkylating agents. Most patients had renal (77%), cardiac (66%), or multiorgan (74%) involvement. Sixty-eight per cent (n = 50) received alkylating agent (mostly cyclophosphamide). Severe adverse events were seen in 45%, most evident in patients with cardiac involvement, with no increased toxicity in patients receiving an alkylator agent. Hematological response (HemR) was obtained in 77% of patients, including 33% very good partial responses and 19% complete responses. Age <70 yr, lack of cardiac and peripheral neurologic involvement, and co-administration of an alkylating agent were associated with significantly improved HemR. NYHA cardiac failure staging was the only independent factor affecting overall survival. Administration of an alkylating agent and the achievement of both HemR and organ response were associated with a statistically significant improved survival in those surviving the first 6 months of induction. First-line bortezomib-based regimen resulted in favorable response and survival in newly diagnosed patients. Co-administration of an alkylating agent improved outcome without increasing treatment-related toxicity.

Effect of amino acid variations in the central region of human serum amyloid A on the amyloidogenic properties.

Human serum amyloid A (SAA) is a precursor protein of the amyloid fibrils that are responsible for AA amyloidosis. Of the four human SAA genotypes, SAA1 is most commonly associated with AA amyloidosis. Furthermore, SAA1 has three major isoforms (SAA1.1, 1.3, and 1.5) that differ by single amino acid variations at two sites in their 104-amino acid sequences. In the present study, we examined the effect of amino acid variations in human SAA1 isoforms on the amyloidogenic properties. All SAA1 isoforms adopted α-helix structures at 4°C, but were unstructured at 37°C. Heparin-induced amyloid fibril formation of SAA1 was observed at 37°C, as evidenced by the increased thioflavin T (ThT) fluorescence and ß-sheet structure formation. Despite a comparable increase in ThT fluorescence, SAA1 molecules retained their α-helix structures at 4°C. At both temperatures, no essential differences in ThT fluorescence and secondary structures were observed among the SAA1 isoforms. However, the fibril morphologies appeared to differ; SAA1.1 formed long and curly fibrils, whereas SAA1.3 formed thin and straight fibrils. The peptides corresponding to the central regions of the SAA1 isoforms containing amino acid variations showed distinct amyloidogenicities, reflecting their direct effects on amyloid fibril formation. These findings may provide novel insights into the influence of amino acid variations in human SAA on the pathogenesis of AA amyloidosis.

Clinical and imaging predictors of 1-year and long-term mortality in light chain (AL) amyloidosis: a 5-year follow-up study.

Light chain amyloidosis (AL) involves multiorgan failure induced by amyloidogenic light chain proteins, and is associated with high mortality. We aimed to identify clinical, laboratory, and imaging parameters that would predict 1-year and long-term AL mortality. Forty-four biopsy-proven AL patients (61.5 ± 12 years, 20 females) underwent clinical evaluation including laboratory assays, echocardiography, and contrast cardiac magnetic resonance imaging (CMR, n = 31) prior to chemotherapy. Patients were prospectively followed for median duration of 62.7 months (interquartile range 35.5 months). Clinical and laboratory parameters were compared between 1-year survivors and nonsurvivors. Univariate Kaplan-Meier survival plots were calculated followed by stepwise logistic regression analysis to assess independent predictors of long-term survival. Eighteen (40.9 %) patients died within 1 year and an additional 10 subjects died during long-term follow-up. Patients who expired within 1 year presented with more advanced class of heart failure, higher alkaline phosphatase and uric acid, lower limb lead voltage on electrocardiography, shorter left ventricular ejection time (ET) on echocardiography, and a higher proportion of late gadolinium enhancement on CMR. On multivariable analysis, only ET ≤240 ms on echocardiography (hazard ratio (HR) 5.07, 95 % confidence interval (CI) 1.83-14.1, P = 0.002) and New York Heart Association functional class II-IV presentation (HR 1.0058, 95 % CI 1.0014-1.0103, P = 0.01) were independent predictors of AL mortality. In conclusion, AL amyloidosis is associated with high 1-year and long-term mortality. Among clinical, laboratory, and imaging parameters tested, an echocardiographic finding of ET ≤240 ms has independent and additive prognostic value to clinical heart failure evaluation in determining long-term survival of AL patients. This result may be important in the early identification of patients at risk.

Report of the task force on designing clinical trials in early (predementia) AD.

BACKGROUND: A large number of promising candidate disease-modifying treatments for Alzheimer disease (AD) continue to advance into phase II and phase III testing. However, most completed trials have failed to demonstrate efficacy, and there is growing concern that methodologic difficulties may contribute to these clinical trial failures. The optimal time to intervene with such treatments is probably in the years prior to the onset of dementia, before the neuropathology has progressed to the advanced stage corresponding to clinical dementia. METHOD: An international task force of individuals from academia, industry, nonprofit foundations, and regulatory agencies was convened to discuss optimal trial design in early (predementia) AD. RESULTS: General consensus was reached on key principles involving the scope of the AD diagnosis, the selection of subjects for trials, outcome measures, and analytical methods. CONCLUSION: A consensus has been achieved in support of the testing of candidate treatments in the early (predementia) AD population.