Efficient and rapid digestion of proteins with a dual-enzyme microreactor featuring 3-D pores formed by dopamine/polyethyleneimine/acrylamide-coated KIT-6 molecular sieve.

The microreactor with two types of immobilized enzymes, exhibiting excellent orthogonal performance, represents an effective approach to counteract the reduced digestion efficiency resulting from the absence of a single enzyme cleavage site, thereby impacting protein identification. In this study, we developed a hydrophilic dual-enzyme microreactor characterized by rapid mass transfer and superior enzymatic activity. Initially, we selected KIT-6 molecular sieve as the carrier for the dual-IMER due to its three-dimensional network pore structure. Modification involved co-deposition of polyethyleneimine (PEI) and acrylamide (AM) as amine donors, along with dopamine to enhance material hydrophilicity. Remaining amino and double bond functional groups facilitated stepwise immobilization of trypsin and Glu-C. Digestion times for bovine serum albumin (BSA) and bovine hemoglobin (BHb) on the dual-IMER were significantly reduced compared to solution-based digestion (1 min vs. 36 h), resulting in improved sequence coverage (91.30% vs. 82.7% for BSA; 90.24% vs. 89.20% for BHb). Additionally, the dual-IMER demonstrated excellent durability, retaining 96.08% relative activity after 29 reuse cycles. Enhanced protein digestion efficiency can be attributed to several factors: (1) KIT-6's large specific surface area, enabling higher enzyme loading capacity; (2) Its three-dimensional network pore structure, facilitating faster mass transfer and substance diffusion; (3) Orthogonality of trypsin and Glu-C enzyme cleavage sites; (4) The spatial effect introduced by the chain structure of PEI and glutaraldehyde's spacing arm, reducing spatial hindrance and enhancing enzyme-substrate interactions; (5) Mild and stable enzyme immobilization. The KIT-6-based dual-IMER offers a promising technical tool for protein digestion, while the PDA/PEI/AM-KIT-6 platform holds potential for immobilizing other proteins or active substances.

Cooperation effect of 4-vinylbenzeneboronic acid/methacrylic acid on affinity of capecitabine imprinted polymer for drug carrier.

Cooperation effect of 4-vinylbenzeneboronic acid (4-VPBA) and methacrylic acid (MAA) was first used to improve the affinity of molecularly imprinted polymer (MIP) for drug delivery. The MIP was prepared using capecitabine (CAP) as template, MAA as functional monomer, 4-VPBA as auxiliary monomer, and trimethylolpropane trimethacrylate as cross-linker. The preparation conditions of the MIPs were optimized by investigating the types of functional monomers, the types of cross-linkers, the ratio of MAA to 4-VPBA, and the ratio of crosslinker to monomer. The results showed that the as-prepared MIP had the maximum imprinting factor of 4.03, which revealed this material had a specific recognition effect on the template molecules. Experiments with in vitro release indicated that the imprinted material released CAP stably for more than 10 h, while the non-imprinted polymer (NIP) released CAP only 4 h. In addition, the pharmacokinetics results from rats showed that the MIP was significantly superior to the NIP and CAP commercial drugs, and the plasma concentration of CAP reached the plateau between 3.0 and 9.0 h. These findings may extend the applicability of noncovalent molecular imprinting, particularly to the cases where the target molecule containing a cis-dihydroxy structure.

Vitamin C Treatment Rescues Prelamin A-Induced Premature Senescence of Subchondral Bone Mesenchymal Stem Cells.

Aging is a predominant risk factor for many chronic conditions. Stem cell dysfunction plays a pivotal role in the aging process. Prelamin A, an abnormal processed form of the nuclear lamina protein lamin A, has been reported to trigger premature senescence. However, the mechanism driving stem cell dysfunction is still unclear. In this study, we found that while passaging subchondral bone mesenchymal stem cells (SCB-MSCs) in vitro, prelamin A accumulation occurred concomitantly with an increase in senescence-associated ß-galactosidase (SA-ß-Gal) expression. Unlike their counterparts, SCB-MSCs with prelamin A overexpression (MSC/PLA) demonstrated decreased proliferation, osteogenesis, and adipogenesis but increased production of inflammatory factors. In a hind-limb ischemia model, MSC/PLA also exhibited compromised therapy effect. Further investigation showed that exogenous prelamin A triggered abnormal nuclear morphology, DNA and shelterin complex damage, cell cycle retardation, and eventually cell senescence. Changes in gene expression profile were also verified by microarray assay. Interestingly, we found that ascorbic acid or vitamin C (VC) treatment could inhibit prelamin A expression in MSC/PLA and partially reverse the premature aging in MSC/PLA, with reduced secretion of inflammatory factors and cell cycle arrest and resistance to apoptosis. Importantly, after VC treatment, MSC/PLA showed enhanced therapy effect in the hind-limb ischemia model. In conclusion, prelamin A can accelerate SCB-MSC premature senescence by inducing DNA damage. VC can be a potential therapeutic reagent for prelamin A-induced aging defects in MSCs.

Synergistic effect of organic-inorganic hybrid monomer and polyhedral oligomeric silsesquioxanes in a boronate affinity monolithic capillary/chip for enrichment of glycoproteins.

A boronate affinity monolith with improved affinity and selectivity for glycoproteins was prepared starting from two monomers. The first is 3-aminopropyltriethoxysilane-methacrylic acid (APTES-MAA), and the other is a polyhedral oligomeric silsesquioxane (POSS) monomer. In the next step, 3-(acrylamido)benzeneboronic acid was adopted as boronate affinity ligand, and ethylene glycol dimethacrylate as the crosslinker, and iso-propanol and octanol as binary porogens. The synergistic effect of APTES-MAA and POSS warrants good affinity and selectivity for glycoproteins, which results in a number of attractive features including (a) a wide operation pH range (from 5 to 8); (b) higher enrichment factors ranging from 19.3 to 20.6; (c) greater recoveries of glycoproteins between 95.8 and 107.1%; (d) lower relative standard deviations of ≤4.2%. Compared to the corresponding APTES-MAA/POSS-free monolith, the new boronate material had 1.7-fold increased glycoprotein recovery from complex samples. Glycoproteins in 500-fold diluted serum samples can be enriched by the boronate monolith. Graphical abstractSchematic representation of the preparation of 3-aminopropyltriethoxysilane-methacrylic acid/polyhedral oligomeric silsesquioxanes boronate affinity monolith. This sorbent exhibits high selectivity and wide pH operation range for capturing glycopeptides.

D-immunized blood donors who are female and who possess at least one HLA-DRB1*15 allele show a propensity for high serum RhIG production.

BACKGROUND: D- individuals with previous D-incompatible pregnancies and/or blood transfusions, as well as those who are actively immunized with small-volume D+ red blood cells (RBCs), are stimulated to produce RhIG. Many factors could influence the stimulation of immunoglobulin production in response to foreign antigen (such as antigen immunogenicity and genetic factors), and it is unknown whether genetic markers could potentially identify responder anti-D donors. STUDY DESIGN AND METHODS: Anti-D donors were assigned a responder profile based on their serum RhIG levels (n = 431). A subset of donors (n = 272) had DNA extracted for polymerase chain reaction genotyping assays for target genes in antigen presentation and pathogen recognition receptors (TLR2, TLR4, CD14, FcγRIIA, and the MHC Class II locus HLA-DRB1). Statistical tests for associations between anti-D donor responder profiles and genetic factors were performed. RESULTS: A large proportion of our donors (38.7%) were classified as nonresponder donors, despite receiving multiple D+ RBC immunizations, whereas female sex was significantly associated with an all-responder profile (p < 0.001). The presence of the DRB1*15 allele and absence of the DRB1*04 allele were more likely to be associated with a responder anti-D donor, although not significantly after Bonferroni correction. A combination of the DRB1*15 allele and female sex was significantly associated with an anti-D donor responder profile. CONCLUSION: This study has identified female sex and the HLA-DRB1*15 allele as potentially useful markers that could be used to screen donors before entry into D immunization programs.

[Expression of Ki-67 in Adult and Children Acute Lymphoblastic Leukemia and Its Clinical Significance].

OBJECTIVE: To investigate the relationship of Ki-67 level with clinical features, immunophenotype, gene mutation, curative efficacy and prognosis in patients with acute lymphoblastic leukemia(ALL). METHODS: Flow cytometry gated at CD45/SSC was used to detect the expression of Ki-67, and the correlation of Ki-67 expression with clinical manifestation, laboratorial indexes, curative efficacy and prognosis was analysed. RESULTS: Ki-67 expression level increased in ALL patients, the median expression rate was 29.22%, there was significant difference as compared with the healthy control (P<0.01). In adult ALL, the median expression rate of Ki-67 in the high-risk group was 31.49%, and the difference was statistically significant as compared with the low-risk group (P<0.05). In children ALL, the median expression rate of Ki-67 in high-risk group was 42.28%, and the difference was statistically significant (P<0.05). The results of unvariate analysis showed that the age, WBC count at newly diagnosed and extramedullary invasion were adverse factors affecting OS and DFS; the results of multivariate analysis showed that age and extramedullary invasion were independent risk factors for OS and DFS in patients. CONCLUSION: Age≥14 years old, intramedullary invasion are the poor factors for prognosis; the Ki-67 level is not an independent factor for the prognosis of patients.

[Effect of RNA Interference-silenced TAK1 on Kasumi-1 cell Proliferation Inhibition Induced by As2O3 and Its Mechanism].

OBJECTIVE: To explore the effect of transforming growth factor-ß activated kinase-1(TAK1) gene silenced by RNA interference on proliferation inhibition of Kasumi-1 cells induced by As2O3 and its mechanism. METHODS: The experiments were divided into 4 groups, including control group(Kasumi-1 cells treated with non-specific siRNA), TAK1 specific siRNA treated group (Kasumi 1 treated with TAK specific siRNA), As2O3 treated group (Kasumi 1 cells treated with As2O3) and combined treated group (Kasumi 1 cells treated with TAK1 specific siRNA plus As2O3). The proliferation inhibition rate of Kasami 1 cells was detected by CCK-8 method, the apoptotic rate of cells was detected by flow eytometry, the expressions of TAK1, phosphorylated c-Jun N-terminal kinase(p-JNK) and apoptosis-related proteins were detected by Western blot. RESULTS: As2O3 could inhibit Kasumi-1 cell proliferation in a dose-dependent manner between 0.5 to 20 µmol/L with IC50 of (3.79±0.36) µmol/L at 24 h, and also inhibit Kasumi-1 cell proliferation in a dose-dependent manner between 0.5 to 10 µmol/L with IC50 of (2.38±0.17) µmol/L at 48 h, but then the inhibitory effect reached plateau. After treating Kasumi-1 cells with TAK1 siRNA and 3.5 µmol/L As2O3 for 24 h, the proliferation inhibition rate was (10.86±1.64)% and (49.80±2.19)%, meanwhile the apoptosis rate was (8.47±0.75)% and (24.78±2.14)%, all significantly higher than those in control group (P<0.05, P<0.01). The proliferation inhibition rate and apoptosis rate of the combined treated group were significantly higher than that in control and single treated groups (P<0.05, P<0.01), TAK1 silencing and 3.5 µmol/L of As2O3 could decrease the expression of TAK1, p-JNK, c-Fos, c-Jun and BCL-2 in different degrees, and increase the expression levels of BAX and the activated (cleaved) caspase-3, 9 with statistically significant differences as compared with control group (P< 0.05). When Kasumi-1 cells were treated with TAK1 specific siRNA plus As2O3 for 24 h, protein expression levels were all significantly greater than that in the single-treated groups (P< 0.05). CONCLUSION: TAK1 silencing and As2O3 can separately and synergistically inhibit Kasumi-1 cell proliferation which probably relates with the inducing apoptosis via the JNK and mitochondrial pathway. Meanwhile, TAK1 silencing enhances the inhibitory effect of As2O3 on Kasumi-1 cell proliferation.

Identification of genetic polymorphisms that predict responder/non-responder profiles to the RhD antigen.

BACKGROUND: Regular plasma donors who produce high titre anti-D immunoglobulin (Ig) are overseen by the Australian Red Cross Blood Service RhD Program. New donors to the program are immunised with small amounts of RhD-positive RBCs, whilst donors who have developed anti-D due to previous RhD-incompatible blood transfusion or pregnancy are boosted with RhD-positive RBCs to maintain a high level of serum anti-D Ig. A significant proportion of primarily immunised individuals do not respond to RhD immunisation and are therefore unnecessarily exposed to the risks involved in RBC sensitisation. STUDY DESIGN AND METHODS: We genotyped 184 anti-D donors for ∼9000 immunological and inflammatory genetic polymorphisms on an Affymetrix GeneChip, and validated the results with a High-Resolution Melt analysis assay. We built and validated a predictive logistic regression model using High Responder and Non-Responder anti-D donors that incorporated highly-associated polymorphisms and gender. RESULTS: High Responder and Non-Responder profiles in anti-D donors were significantly associated with a shortlist of 13 genetic polymorphisms and sex of the donor. The derivation of a logistic regression model showed an accuracy rate of 92.6% that was subsequently validated as 60.0% with an independent set of donor samples. CONCLUSION: This study has developed a logistic regression model and a genotyping assay that can predict the responder profiles of anti-D donors and could potentially be applied to new donors and transfusion-dependent patients in a clinical setting. Additionally, target polymorphisms identified in immunological genes could help to elucidate the immunomodulatory pathways regulating the immune response to the RhD antigen, and to other RBC antigens.

Cuffed-tunneled hemodialysis catheter survival and complications in pediatric patients: a single-center data analysis in China.

This study aims to evaluate the outcome and complications of cuffed-tunneled catheters in pediatric patients. Between January 2010 and December 2013, 16 pediatric patients with end-stage renal disease (ESRD) were included. 21 cuffed-tunneled hemodialysis catheters were inserted in patients for long-term hemodialysis access. No serious complications were observed in all patients receiving catheter insertion operation, except one with hemopneumothorax. Median survival time was 413.5 days, with rate being 67.5% in the first year, 51.5% in the second year and 43.6% in the third year. Among attempted catheter insertions, 21 (100%) achieved successful vascular access with 13 (61.9%) being remained for the required period and 8 (38.1%) being removed due to death, intractable blood or tunnel infections, catheter thrombosis or malposition. The overall rate of catheter-related infections, thrombosis and malposition was 7.3, 23.4 and 3.4 episodes/1000 catheter days, respectively. Cuffed-tunneled hemodialysis catheters could be effectively used for maintenance of hemodialysis vascular access for pediatric patients with ESRD. Various surveillance measures should be taken to ensure cuffed-tunneled catheters' long-term patency.

Heatstroke induces liver injury via IL-1ß and HMGB1-induced pyroptosis.

BACKGROUND & AIMS: Liver injury is a common complication of heat stroke (HS), and often constitutes a direct cause for patient death. The cellular and molecular mechanism underlying HS-induced liver injury remains unclear. Recent evidence indicates that inflammasome plays an important role in mediating sterile inflammation triggered by tissue damage. Using a rat HS model, we identified a novel mechanism by which inflammasome-dependent interleukin-1ß (IL-1ß) activation and hepatocyte pyroptosis mediate HS-induced liver injury. METHODS: To induce HS, rats were subjected to heat exposure. Inhibition of inflammasomes was achieved by RNA silencing and pharmacologic inhibitor prior to heat exposure. Inflammasome assembly, caspase-1 activation, histological changes, as well as serum levels of liver enzymes were measured. RESULTS: We demonstrated that the onset of HS activated inflammasome in the liver as evidenced by increased capase-1 activity and the association of inflammasome components NOD-like receptor family pyrin domain containing 3 (Nlrp3) and apoptosis speck-like protein containing a caspase-recruitment domain (ASC); and the activated inflammasome, in turn, induced IL-1ß activation and hepatocyte pyroptosis, and subsequent augmented liver injury. HS-induced hepatocyte inflammasome activation seems to be high-mobility group box 1 (HMGB1) dependent. Inhibition of Nlrp3, caspase-1, or HMGB1 prevented HS-induced liver inflammation and ameliorated liver injury. CONCLUSIONS: These findings demonstrate an important role of HMGB1 in mediating inflammasome activation in the development of liver injury following HS, and suggest that targeting inflammasome may represent a novel therapeutic strategy to limit cell death and prevent liver failure after HS.