[Research progress of chronic obstructive pulmonary disease in young people and pre-COPD].

Conventional wisdom holds that the onset of chronic obstructive pulmonary disease (COPD) is usually in older people. However, with extended follow-up in large cohort studies, the trajectory of lung function development has been gradually delineated, indicating that the decline of lung function may originate early in life. In addition, a large number of studies have shown that people with chronic respiratory symptoms, pulmonary imaging changes and abnormal lung physiology, but not in line with pulmonary function diagnosis of COPD, tend to develop COPD in the future and may have a worse prognosis, suggesting the necessity of early intervention. The GOLD 2022 report proposes a series of terms related to COPD, including COPD in young people and pre-COPD, opening up new opportunities for the prevention, early diagnosis and treatment of COPD. These concepts also guide the study design of the biological mechanism of COPD and the trajectory of disease progression. This article reviews the research progress of COPD in young people and pre-COPD to attract more attention in clinical practice.

Separation, purification, and identification of flagellin, and preparation of its antisera.

The aim of this study was to separate, purify, and identify Salmonella paratyphi A flagellin, and to prepare its antisera. Primary flagellin was isolated from S. paratyphi A using the acid lysis method. The flagellin was purified with weak anion exchange chromatography and the protein was identified with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot, and negative staining with phosphotungstic acid with scanning electron microscopy (SEM). The production of the obtained flagellin was then quantified. New Zealand white rabbits were then immunized with the isolated flagellin, the presence of serum anti-flagellin antibodies was assessed with the immunoblot test, and its potency was determined with the double immunodiffusion test. The results of SDS-PAGE showed that the molecular weight (m.w.) of the purified flagellin was 52 x 10(3). The immunoblot test also showed a band at 52 x 10(3) m.w. The SEM results showed that the flagellin was filamentous. These three results showed that the protein was homogeneous. The protein quantification analysis found that 4.8 ± 0.5 mg flagellin could be extracted per 1 g wet weight bacteria. The titer of the anti-flagellin antiserum was 1:64. Through this method, we obtained high productions of flagellin, which could be easily purified, identified, and prepared into high titer antiserum.

Long non-coding RNA FOXP4-AS1 acts as an adverse prognostic factor and regulates proliferation and apoptosis in nasopharyngeal carcinoma.

OBJECTIVE: Nasopharyngeal carcinoma (NPC) is one of the most common malignancies worldwide. In The Cancer Genome Atlas (TCGA) database, the expression level of lncRNA forkhead box P4 antisense RNA 1 (FOXP4-AS1) is higher in NPC samples than in normal samples. PATIENTS AND METHODS: Quantitative Real-time PCR and Western blotting were performed to detect the expression level of RNA and protein. Luciferase reporter assay ran to test the interactions between FOXP4-AS1 and miR-423-5p and STMN1. Subcellular fractionation assay was used to determine the subcellular localization of FOXP4-AS1. The tumor-promotion functions of FOXP4-AS1 were determined by both in vitro and in vivo assays. RESULTS: The expression of FOXP4-AS1 was up-regulated in 80 cases with NPC, and these patients with a poor prognosis. Functionally, high expression of FOXP4-AS1 in NPC was connected with promoted cell proliferation and inhibited apoptosis. Moreover, FOXP4-AS1 is located in the cytoplasm of CNE1 (NPC cell lines). Mechanistically, FOXP4-AS1 up-regulated STMN1 on post-transcriptional regulation by means of miR-423-5p. CONCLUSIONS: Our present study demonstrated that high expression of FOXP4-AS1 in NPC portended poor outcomes. FOXP4-AS1upregulated STMN1 by interacting with miR-423-5p as a competing endogenous RNA (ceRNA) to promote NPC progression.

Screening and isolation of an organic solvent-tolerant bacterium for high-yield production of organic solvent-stable protease.

Forty-three strains were screened from crude oil-contaminated samples by toluene and cyclohexane enrichment in medium. Ten of these strains demonstrated high protease activity on skim-milk agar. Among them, the PT121 isolate, identified as Pseudomonas aeruginosa, was selected based on its extracellular protease stability in the presence of hydrophilic organic solvents. The crude protease also retained most of its activity up to at least 14 days in the presence of various organic solvents at 50% concentration, and the protease activity in production medium was 10,876U/ml after 72h incubation. This protease showed high activity as a catalyst for aspartame precursor Cbz-Asp-Phe-NH2 synthesis in the presence of 50% dimethylsulfoxide (DMSO).

Capturing intracellular oncogenic microRNAs with self-assembled DNA nanostructures for microRNA-based cancer therapy.

Aberrantly overexpressed oncogenic microRNAs (miRNAs, miRs) are excellent targets for therapeutic interventions. Nevertheless, thus far, little progress has been made in developing miRNA-based drugs and techniques for clinical applications, especially for overexpressed miRNAs. In this study, we demonstrate that self-assembled DNA nanostructures bearing multiple DNA sequences that are complementary to a target miRNA can effectively capture the overexpressed oncogenic miRNA and subsequently inhibit cancer cell proliferation. Specifically, a DNA nanotube structure that carries functional DNA segments (single-stranded, duplex and hairpin forms) was designed and synthesized to capture two well-known overexpressed miRNAs, miR-21 and miR-155. It was found that all three DNA nanotubes significantly reduced both miRNA levels and inhibited cancer cell growth. Moreover, the capture efficiency was highly concentration dependent and was associated with the structural design of the DNA nanotube. These results demonstrate that through careful design, programmable DNA nanostructures can hijack the natural cellular machinery and can serve as nucleic acid drugs themselves. The concept of using self-assembled DNA nanostructures to disrupt the intracellular machinery for therapeutic purposes opens a new paradigm for exploiting self-assembled DNA nanostructures for miRNA-based anticancer therapy.

Efficient conversion of itaconic acid to (S)-(+)-citramalic acid by Alcaligenes xylosoxydans IL142.

The effective production of (S)-(+)-citramalic acid from itaconic acid with an enantiomeric purity of more than 99.9% was successfully achieved using resting cells of a newly isolated strain, Alcaligenes xylosoxydans IL142. The highest conversion activity was obtained with an itaconic acid concentration of 65.0 g.l(-1). After 30 h of reaction, 68.9 g.l(-1) of (S)-(+)-citramalic acid was produced from 65.0 g.l(-1) of itaconic acid. This is equivalent to a molar yield of 93.1%. This production process is of considerable economic significance because only very few by-products were detected. The ATP and CoA requirements for (S)-(+)-citramalic acid formation from itaconic acid were evaluated using crude cell-free enzymes. Addition of succinate enhanced the production of (S)-(+)-citramalic acid in the presence of CoA and ATP. These results suggest the existence of strong citramalyl-CoA transferase activity in the cell.

Enzymatic formation of a novel cell-adhesive hydrogel based on small peptides with a laterally grafted l-3,4-dihydroxyphenylalanine group.

We rationally designed a bioadhesive supramolecular hydrogel by introducing L-3,4-dihydroxylphenylalanine (DOPA) groups while properly integrating the enzymatic reactions and self-assembly processes. The effective presence of the catechol groups successfully promoted the adhesion and proliferation of human fibroblast cells.

Primary dual defect of cholesterol and bile acid metabolism in liver of patients with intrahepatic calculi.

BACKGROUND/AIMS: Intrahepatic calculi, which are characterized by cholesterol-rich pigment stones, are highly prevalent in East Asia. Their pathogenesis remains unknown. To elucidate the etiological factors underlying the formation of cholesterol-supersaturated bile, which leads to the formation of cholesterol-rich pigment stones cholesterol and bile acid de novo syntheses in the liver were studied. METHODS: Liver specimens were assayed for the catalytic activities and steady-state messenger RNA levels of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase and cholesterol 7 alpha-hydroxylase. RESULTS: The activity of HMG-CoA reductase, consistent with the messenger RNA level, was significantly higher in 13 patients with intrahepatic grown pigment stones (11.2 +/- 1.3 pmol.min-1.mg protein-1 [mean +/- SEM; P < 0.0001] for affected hepatic lobes and 13.4 +/- 1.7 [P < 0.0001] for unaffected ones [P < 0.0001]) than in 19 control subjects (6.4 +/- 0.4) and in 29 patients with gallbladder cholesterol stones (2.1 +/- 0.1). On the other hand, the activity of 7 alpha-hydroxylase, consistent with the messenger RNA level, was significantly lower in patients with intrahepatic brown pigment stones (2.8 +/- 0.5 pmol.min-1.mg protein-1 [P < 0.0001] for affected lobes and 2.6 +/- 0.5 [P < 0.0001] for unaffected ones) than in control subjects (6.0 +/- 0.6) and in patients with cholesterol stones (5.1 +/- 0.5). CONCLUSIONS: In intrahepatic calculi, the formation of supersaturated bile and cholesterol-rich pigment stones may be attributed to the primary dual defect of up-regulated cholesterogenesis and down-regulated bile acid synthesis in the liver.

Alterations of bile acid composition in gallstones, bile, and liver of patients with hepatolithiasis, and their etiological significance.

A detailed comparison was made of the bile acid composition in gallstones (brown pigment stones) and paired bile and liver from both affected and unaffected lobes by gallstones, which were taken at operation from 16 patients with hepatolithiasis, with the aim of elucidating whether stone formation is derived from possible local disturbances limited to intrahepatic bile ducts. Brown pigment stones in the intrahepatic bile ducts, most of which were accompanied by bile with high cholesterol saturation, had significantly more cholesterol, and less calcium bilirubinate and bile acid than those found in the extrahepatic bile ducts. Intrahepatic gallstones had significantly lower amounts of secondary and unconjugated bile acids, the bile acids modified by bacterial intervention, than extrahepatic stones. Bile specimens from both affected and unaffected lobes showed significantly increased molar percentages of cholesterol and decreased percentages of bile acids than bile from controls. In contrast, liver specimens from both lobes showed significantly higher concentrations of total bile acids. Secondary bile acids were present in a much lower proportion in bile and liver from both lobes than in bile and liver from controls. On the other hand, unconjugated bile acids were present in a much higher proportion in bile and liver from patients and only in negligible amounts in bile from controls. Furthermore, the plasma levels of mevalonate and those of 7 alpha-hydroxy-4-cholestene-3-one were found to be significantly higher and lower in patients than in controls, respectively, indicating that in hepatolithiasis cholesterol synthesis might increase and bile acid synthesis might decrease in the liver. These findings suggested that alterations of bile acid composition in gallstones, bile, and liver of patients with hepatolithiasis may be attributed to not only secondary changes resulting from local disturbances limited to intrahepatic bile ducts but also possible primary alterations of hepatocyte metabolism, such as bile acid conjugation and primary defects in cholesterol and bile acid synthesis.

Increase of deoxycholate in supersaturated bile of patients with cholesterol gallstone disease and its correlation with de novo syntheses of cholesterol and bile acids in liver, gallbladder emptying, and small intestinal transit.

A total of 100 nonobese and normolipidemic subjects (29 control subjects, 49 patients with cholesterol stones [CSs], and 22 patients with brown pigment stones) were studied to elucidate the pathogenetic contributions of deoxycholate (DC) to supersaturated bile formation with special reference to de novo syntheses of cholesterol and bile acids in the liver. A higher proportion of DC was observed in gallbladder bile from patients with CSs (CSs; 21.7 +/- 1.4%, mean +/- SEM, vs. control subjects; 10.2 +/- 0.9%). Cholesterol saturation in bile was elevated parallel to the increase of DC (r = .48; P = .0002), irrespective of the existence of stones. In a comparison between the 52 subjects with increased DC in bile (> 10% of biliary bile acids) and the 20 subjects without the increase (< 10%), the molar percentage of cholesterol in bile was significantly higher in the former (9.4 +/- 0.5%) than in the latter (6.7 +/- 0.4%) (P < .001). Consistent with the decrease in steady-state level of low-density lipoprotein (LDL) receptor-messenger RNA (mRNA), the catalytic activity and mRNA level of microsomal hepatic 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme for de novo cholesterol synthesis, were significantly lower in the former (2.9 +/- 0.3 pmol/min/mg protein) than in the latter (5.1 +/- 0.6) (P < .0001). Biliary molar percentage of bile acids was significantly lower in the former (69.8 +/- 1.1%) than in the latter (75.2 +/- 1.5%) (P < .01). However, contrary to expectations, the catalytic activity and mRNA level of cholesterol 7 alpha-hydroxylase, the rate-limiting enzyme for bile acid synthesis, were significantly higher in the former (5.8 +/- 0.4 pmol/min/mg protein) than in the latter (3.7 +/- 0.6) (P < .01). The magnitude of the impaired gallbladder emptying (control subjects; 78.4 +/- 4% vs. CSs; 58 +/- 3%; P < .0005) together with the prolonged small intestinal transit (control subjects; 126 +/- 9 minutes vs. CSs; 198 +/- 9 minutes; P < .01) correlated significantly with the increased percentage of DC in bile. It is concluded that in cholesterol gallstone disease an increase of DC in bile, linked to an impaired gallbladder emptying together with a prolonged small intestinal transit, may play a significant role in downregulating de novo cholesterol synthesis but not bile acid synthesis in the liver.(ABSTRACT TRUNCATED AT 400 WORDS)