A New "Mix and Measure" Method for Rapid Quantitative Determination of Alkalinity Based on Proton Equilibrium and Definite Integral of Buffer Capacity.

Alkalinity is crucial in environmental control of ecosystems, wastewater and drinking water treatment, and industrial process control. In this work, we reported a new equation for calculating alkalinity based on the definition of buffer capacity in acid-base buffer solutions and the quantitative relationship between the buffer capacity and pH changes. A "mix and measure" method was developed using this new equation, involving mixing a solution with unknown alkalinity and a standard solution in a specific volume ratio, followed by measuring the pH after mixing. The alkalinity of the solution can be calculated using the newly developed equation. The "mix and measure" method is much more efficient than traditional titration methods for determination of alkalinity because it is restricted by the titration stoichiometric point. Additionally, we demonstrated the rapid determination of the alkalinity for a series of solutions using a portable detection system. This system exhibited precision and accuracy comparable to those of traditional titration methods. The portable system offers great potential for the on-site and real-time determination of alkalinity for industrial control and environmental monitoring purposes.

Remote Ischemic Conditioning and Outcomes in Acute Ischemic Stroke With Versus Without Large Artery Atherosclerosis.

BACKGROUND: RICAMIS trial (The Remote Ischemic Conditioning for Acute Moderate Ischemic Stroke) has demonstrated efficacy of remote ischemic conditioning (RIC) in acute ischemic stroke. We conducted a post hoc analysis of RICAMIS to investigate whether large artery atherosclerosis (LAA) subtype contributed to the outcomes. METHODS: This is a post hoc analysis of the RICAMIS trial. Patients randomized to RIC group and Control group in full analysis set of RICAMIS were classified into LAA and non-LAA subtypes. The primary outcome was excellent functional outcome at 90 days, defined as modified Rankin Scale score of 0 to 1. Compared with patients receiving usual care, we investigated the association of RIC effect with outcomes in stroke subtypes and the interaction between RIC effect and stroke subtypes. The primary analysis was adjusted analysis. RESULTS: Among 1773 patients, 516 were assigned to LAA subtype (229 in the RIC group and 287 in the control group) and 1257 to non-LAA subtype (633 in the RIC group and 624 in the control group). Median age was 65 years, and 34.2% were women. A higher proportion of primary outcome was found to be associated with RIC treatment in LAA subtype (adjusted risk difference, 11.4% [95% CI, 3.6%-19.2%]; P=0.004), but not in non-LAA subtype (adjusted risk difference, 4.1% [95% CI, -1.1% to 9.3%]; P=0.12). There was no significant interaction between RIC effect and stroke subtypes (P=0.12). CONCLUSIONS: Patients with LAA subtype may benefit from RIC after stroke with respect to excellent functional outcome at 90 days. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03740971.

Effect of Argatroban Plus Intravenous Alteplase vs Intravenous Alteplase Alone on Neurologic Function in Patients With Acute Ischemic Stroke: The ARAIS Randomized Clinical Trial.

Importance: Previous studies suggested a benefit of argatroban plus alteplase (recombinant tissue-type plasminogen activator) in patients with acute ischemic stroke (AIS). However, robust evidence in trials with large sample sizes is lacking. Objective: To assess the efficacy of argatroban plus alteplase for AIS. Design, Setting, and Participants: This multicenter, open-label, blinded end point randomized clinical trial including 808 patients with AIS was conducted at 50 hospitals in China with enrollment from January 18, 2019, through October 30, 2021, and final follow-up on January 24, 2022. Interventions: Eligible patients were randomly assigned within 4.5 hours of symptom onset to the argatroban plus alteplase group (n = 402), which received intravenous argatroban (100 µg/kg bolus over 3-5 minutes followed by an infusion of 1.0 µg/kg per minute for 48 hours) within 1 hour after alteplase (0.9 mg/kg; maximum dose, 90 mg; 10% administered as 1-minute bolus, remaining infused over 1 hour), or alteplase alone group (n = 415), which received intravenous alteplase alone. Both groups received guideline-based treatments. Main Outcomes and Measures: The primary end point was excellent functional outcome, defined as a modified Rankin Scale score (range, 0 [no symptoms] to 6 [death]) of 0 to 1 at 90 days. All end points had blinded assessment and were analyzed on a full analysis set. Results: Among 817 eligible patients with AIS who were randomized (median [IQR] age, 65 [57-71] years; 238 [29.1%] women; median [IQR] National Institutes of Health Stroke Scale score, 9 [7-12]), 760 (93.0%) completed the trial. At 90 days, 210 of 329 participants (63.8%) in the argatroban plus alteplase group vs 238 of 367 (64.9%) in the alteplase alone group had an excellent functional outcome (risk difference, -1.0% [95% CI, -8.1% to 6.1%]; risk ratio, 0.98 [95% CI, 0.88-1.10]; P = .78). The percentages of participants with symptomatic intracranial hemorrhage, parenchymal hematoma type 2, and major systemic bleeding were 2.1% (8/383), 2.3% (9/383), and 0.3% (1/383), respectively, in the argatroban plus alteplase group and 1.8% (7/397), 2.5% (10/397), and 0.5% (2/397), respectively, in the alteplase alone group. Conclusions and Relevance: Among patients with acute ischemic stroke, treatment with argatroban plus intravenous alteplase compared with alteplase alone did not result in a significantly greater likelihood of excellent functional outcome at 90 days. Trial Registration: ClinicalTrials.gov Identifier: NCT03740958.

Global analysis of DNA methylation in hepatocellular carcinoma by a liquid hybridization capture-based bisulfite sequencing approach.

BACKGROUND: Epigenetic alterations, such as aberrant DNA methylation of promoter and enhancer regions, which lead to atypical gene expression, have been associated with carcinogenesis. In hepatocellular carcinoma (HCC), genome-wide analysis of methylation has only recently been used. For a better understanding of hepatocarcinogenesis, we applied an even higher resolution analysis of the promoter methylome to identify previously unknown regions and genes differentially methylated in HCC. RESULTS: Optimized liquid hybridization capture-based bisulfite sequencing (LHC-BS) was developed to quantitatively analyze 1.86 million CpG sites in individual samples from eight pairs of HCC and adjacent tissues. By linking the differentially methylated regions (DMRs) in promoters to the differentially expressed genes (DEGs), we identified 12 DMR-associated genes. We further utilized Illumina MiSeq combining the bisulfite sequencing PCR approach to validate the 12 candidate genes. Analysis of an additional 78 HCC pairs on the Illumina MiSeq platform confirmed that 7 genes showed either promoter hyper-methylation (SMAD6, IFITM1, LRRC4, CHST4, and TBX15) or hypo-methylation (CCL20 and NQO1) in HCC. CONCLUSIONS: Novel methylome profiling provides a cost-efficient approach to identifying candidate genes in human HCC that may contribute to hepatocarcinogenesis. Our work provides further information critical for understanding the epigenetic processes underlying tumorigenesis and development of HCC.

Improved tagmentation-based whole-genome bisulfite sequencing for input DNA from less than 100 mammalian cells.

AIM: To develop a whole-genome methylation sequencing method that fulfills the needs for studies using ultra-low-input DNA. MATERIALS & METHODS: The tagmentation-based whole-genome bisulfite sequencing (T-WGBS) technology is modified, enabling stable library construction with complexity from minimally 0.5 ng of initial genomic DNA, which equals less than 100 mammalian cells. RESULTS: We thoroughly assessed the performance of this T-WGBS method by sequencing the methylomes of a rice strain and pre-implantation embryos of rhesus monkey and compare to traditional WGBS approach, thereby demonstrating the efficacy of this new approach. CONCLUSION: This new approach is highly attractive for the complete methylome analysis of very few cells, for example, mammalian pre-implantation embryos, or tiny human biopsy specimens.

Direct ChIP-bisulfite sequencing reveals a role of H3K27me3 mediating aberrant hypermethylation of promoter CpG islands in cancer cells.

The model describing that aberrant CpG island (CGI) methylation leads to repression of tumour suppressor genes in cancers has been influential, but it remains unclear how such aberrancy is induced. Recent studies provided clues indicating that promoter hypermethylation in cancers might be associated with PRC target genes. Here, we used ChIP-BS-seq to examine methylation of the DNA fragments precipitated by the antibodies to both H3K27me3 and H3K4me3 histone modifications. We showed that, for a set of genes highly enriched with H3K27me3 both in cancer and normal cells, CGI promoters were aberrantly hypermethylated only in cancer cells in comparison with normal cells. In contrast, such aberrant CGI hypermethylation in cancer promoters that were deficient of H3K27me3 was not notable. Furthermore, we confirmed that these genes were consistently hypermethylated in TCGA primary cancer cells. These works support the association between H3K27me3 and DNA methylation marks for specific cancer genes and will spur future work on combined histone and DNA methylation that could define cancer's epigenetic abnormalities.