Effects of Lactobacillus acidophilus AC on the growth, intestinal flora and metabolism of zebrafish (Danio rerio).

The intensive aquaculture model has resulted in a heightened prevalence of diseases among farmed animals. It is imperative to identify healthy and efficacious alternatives to antibiotics for the sustainable progression of aquaculture. In this investigation, a strain of Lactobacillus acidophilus AC was introduced into the cultural water at varying concentrations (105 CFU/mL, 106 CFU/mL, 107 CFU/mL) to nourish zebrafish (Danio rerio). The findings revealed that L. acidophilus AC effectively increased the growth performance of zebrafish, improved the ion exchange capacity of gills, and enhanced hepatic antioxidant and immune-enzyme activities. Furthermore, L. acidophilus AC notably enhanced the intestinal morphology and augmented the activity of digestive enzymes within the intestinal tract. Analysis of intestinal flora revealed that L. acidophilus AC exerted a significant impact on the intestinal flora community, manifested by a reduction in the relative abundance of Burkholderiales, Candidatus_Saccharibacteria_bacterium, and Sutterellaceae, coupled with an increase in the relative abundance of Cetobacterium. Metabolomics analysis demonstrated that L. acidophilus AC significantly affected intestinal metabolism of zebrafish. PG (i-19:0/PGE2) and 12-Hydroxy-13-O-d-glucuronoside-octadec-9Z-enoate were the metabolites with the most significant up- and down-regulation folds, respectively. Finally, L. acidophilus AC increased the resistance of zebrafish to Aeromonas hydrophila. In conclusion, L. acidophilus AC was effective in enhancing the health and immunity of zebrafish. Thus, our findings suggested that L. acidophilus AC had potential applications and offered a reference for its use in aquaculture.

In-Vitro Diagnostic Reagent Evaluation of Commercially Available Cardiac Troponin I Assay Kits Using H/D Exchange Mass Spectrometry for Antibody-Epitope Mapping.

Cardiac troponin I (cTnI) is the biomarker of choice and considered a gold standard for the diagnosis of acute myocardial infarction. However, the quantitative results of cTnI assay kits from different manufacturers are not comparable. Based on the H/D exchange mass spectrometry (HDX-MS) workflow, we developed an in-vitro diagnostic reagent antibody evaluation strategy to analyze the interactions of epitopes and antibody cocktails─(R195, F12, S13) and (D1, D2, pAb2). The HDX results indicate that the quantitative result bias of the different reagents originates from the ability of antibodies to recognize various cTnI complex forms, such as free cTnI, hydrolyzed cTnI, and cTnI combined with cTnT or TnC as binary or ternary complexes (cTnIC, cTnTIC), in blood based on different epitopes. The data obtained from the peptide HDX of interest after treatment with various antibody cocktails clearly indicated epitope specificity. The consistency of quantitative results can be improved by a thorough investigation into the epitopes recognized by the antibodies of various diagnostic kits, which will lead to the standardization of cTnI diagnosis.

Commutability assessment of reference materials for homocysteine.

OBJECTIVES: Commutability of reference materials is essential for ensuring the traceability of patient measurement results and the technical basis for the use of reference materials. Commutability is only relevant for matrixed reference material; it is a prerequisite for the accuracy and authenticity of calibration methods. In this study, we evaluated the commutability of reference materials for homocysteine. METHODS: Five conventional measurement methods were applied to simultaneously measure 30 serum samples and seven homocysteine reference materials from the National Institute of Standards and Technology and the National Institute of Metrology. Liquid chromatography tandem-mass spectrometry was used as a reference method. Two methods were used to evaluate the commutability of the seven reference materials according to the Clinical and Laboratory Standards Institute EP30-A and the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) commutability assessment document. RESULTS: Among 35 combinations of the five conventional methods and seven reference materials, after evaluation in accordance with the EP30-A, the seven reference materials passed the commutability assessment, and 34 combinations were commutable. According to the IFCC, the commutability evaluation of 28 combinations was conclusive (commutable or non-commutable), while results for the remaining seven combinations could not be determined. CONCLUSIONS: The homocysteine reference materials showed good commutability. The sensitivity of the measurement procedure, measurement deviation and uncertainty, and differences in the "measurand" selected by different methods may affect the evaluation results. Additionally, different judgment standards for different methods may explain the observed variations in evaluation results.

Epitope mapping of antibodies in C-reactive protein assay kits by hydrogen-deuterium exchange mass spectrometry explains differential results across kits.

C-Reactive protein (CRP) is an important marker for in vitro diagnosis (IVD) of inflammation. However, CRP immunoturbidimetric kits from different manufacturers exhibit inconsistency in evaluation, making clinical diagnosis challenging. The use of immunological methods in diagnosis means that the differences in epitopes across kits may directly lead to inconsistent results. Therefore, to provide consistent results, it is essential to perform epitope mapping of different kits. The composition of antibodies in a single kit is typically complex, with a combination of polyclonal antibodies or monoclonal antibodies. Here, we show an epitope screening strategy for complex antibodies in a kit based on hydrogen-deuterium exchange mass spectrometry (HDX-MS). We applied this workflow to successfully map the epitopes for three kits from three different manufacturers and compared their quantitative results. We obtained different quantitative results using kits from different manufacturers upon epitope mapping, confirming the correlation between the quantitative results and the epitopes. Thus, we have established a workflow based on HDX-MS to screen epitopes in IVD kits. This work helps determine the quantitative accuracy of a kit based on structural information, can guide the design and production of IVD reagents, and further improves the accuracy of IVD.

Group Visits Improve Health in Patients With COPD in Post-Discharge Transition Period.

OBJECTIVE: Continuous care during the post-discharge transition period is necessary for convalescence in patients with chronic obstructive pulmonary disease (COPD). This study aimed to evaluate the effect of group visits on the health of patients with COPD during the post-discharge transition period. METHODS: In this prospective randomized study, a total of 116 patients with COPD post-discharge were randomly assigned to either the control group (n = 57) or the group visit intervention group (GV; n = 59). A healthy lifestyle, quality of life, self-efficacy and lung function before and after the intervention and acute COPD exacerbation(s) during the intervention were recorded and analyzed. RESULTS: Healthy lifestyle and self-efficacy scores were higher in the GV group after compared with before the intervention and the control group. Lung function was improved in both groups, with greater improvement in the GV group. In addition, the frequency of outpatient emergency services and hospitalizations due to acute COPD exacerbations was lower in the GV group compared with the control group. CONCLUSION: Group visits are efficient administration models in patients with COPD. Through health education and companion support, group visits increase patients' self-efficacy, promote patients' transition to a healthy lifestyle, improve their quality of life, reduce acute exacerbations and lower medical costs during the post-discharge transition period.

Research advances in hydrogen-deuterium exchange mass spectrometry for protein epitope mapping.

With the development of biomedical technology, epitope mapping of proteins has become critical for developing and evaluating new protein drugs. The application of hydrogen-deuterium exchange for protein epitope mapping holds great potential. Although several reviews addressed the hydrogen-deuterium exchange, to date, only a few systematic reviews have focused on epitope mapping using this technology. Here, we introduce the basic principles, development history, and review research progress in hydrogen-deuterium exchange epitope mapping technology and discuss its advantages. We summarize the main hurdles in applying hydrogen-deuterium exchange epitope mapping technology, combined with relevant examples to provide specific solutions. We describe the epitope mapping of virus assemblies, disease-associated proteins, and polyclonal antibodies as examples of pattern introduction. Finally, we discuss the outlook of hydrogen-deuterium exchange epitope mapping technology. This review will help researchers studying protein epitopes to gain a more comprehensive understanding of this technology.

Absolute quantification methods for Prostate-Specific antigen by Isotope-Dilution mass spectrometry.

Prostate-specific antigen (PSA) is a diagnostic marker for prostate cancer; however, because it is a macromolecular glycoprotein with complex and diverse isoforms, it is difficult to standardize clinical PSA detection results. To overcome this limitation, herein, naturally extracted PSA was characterized as free PSA (fPSA), and the PSA solution was successfully quantified by amino acid analysis coupled with isotope-dilution mass spectrometry (AAA-IDMS) and enzymatic hydrolysis-IDMS; the results could be traced to the International System of Units (SI) through absolutely quantified amino acids and peptides. After protein hydrolysis or digestion condition optimization, amino acids and signature peptides were detected by liquid chromatography-mass spectrometry with the multiple reaction monitoring mode. The mass concentrations of PSA obtained through AAA-IDMS and enzymatic hydrolysis-IDMS were (75.3 ±â€¯1.5) µg/g (k = 2) and (74.7 ±â€¯1.7) µg/g (k = 2), respectively. The PSA weighted average mass concentration was (75.0 ±â€¯1.6) µg/g (k = 2). The consistency assessment between the two methods was successfully validated, ensuring absolute quantitative accuracy. This study lays the foundation for the development of high-order reference materials for the clinical detection of PSA, which can improve the accuracy, reliability, and consistency of clinical PSA test results.

Organophosphate ester in surface water of the Pearl River and South China Sea, China: Spatial variations and ecological risks.

This study focused on investigating the concentrations, compositional profiles, partitioning behaviors and spatial variations of organophosphate esters (OPEs) in the Pearl River (PR), South China Sea (SCS) region, to evaluate their environmental risks. ∑OPEs concentrations in the surface water of the PR ranged from 117.5 to 854.8 ng/L in the dissolved phase and from 0.5 to 13.3 ng/L in the suspended particulate matter. In the surface seawaters of the northern and western parts of the SCS, ∑OPEs concentrations were 1.3-17.6 ng/L (mean: 6.7 ± 5.2) and 2.3-24.4 ng/L (mean: 7.6 ± 5.5), respectively. The percentage of chlorinated OPEs in surface water samples from the PR to the SCS was 79 ± 15%. Tripentyl phosphate (TPeP) (average: 28.3%) and triphenylphosphate (TPhP) (average: 9.6%) exhibited significant particulate fraction. A significant negative correlation (p < 0.05) between salt concentration and OPE congeners in seawater suggested that river runoff predominantly introduced OPEs into the coastal waters of the SCS. The findings also showed higher levels of OPEs in the PR and estuary than in offshore waters. The OPE loading from the PR into the SCS was estimated to be ∼119 t y-1. The presence of TCEP (RQmax = 2.1), TnBP (RQmax = 0.48) and TPhP (RQmax = 0.3) in PR water samples pose a high risk to aquatic organisms, whereas OPEs (RQ < 0.1) in SCS water samples do not pose a threat to aquatic organisms. This research emphasizes the environmental fate and impact of OPEs on surface waters of the PR and SCS.

Hierarchical palladium catalyst for highly active and stable water oxidation in acidic media.

Acidic water electrolysis is of great importance for boosting the development of renewable energy. However, it severely suffers from the trade-off between high activity and long lifespan for oxygen evolution catalysts on the anode side. This is because the sluggish kinetics of oxygen evolution reaction necessitates the application of a high overpotential to achieve considerable current, which inevitably drives the catalysts far away from their thermodynamic equilibrium states. Here we demonstrate a new oxygen evolution model catalyst-hierarchical palladium (Pd) whose performance even surpasses the benchmark Ir- and Ru-based materials. The Pd catalyst displays an ultralow overpotential (196 mV), excellent durability and mitigated degradation (66 µV h-1) at 10 mA cm-2 in 1 M HClO4. Tensile strain on Pd (111) facets weakens the binding of oxygen species on electrochemical etching-derived hierarchical Pd and thereby leads to two orders of magnitudes of enhancement of mass activity in comparison to the parent Pd bulk materials. Furthermore, the Pd catalyst displays the bifunctional catalytic properties for both oxygen and hydrogen evolutions and can deliver a current density of 2 A cm-2 at a low cell voltage of 1.771 V when fabricated into polymer electrolyte membrane electrolyser.

One-stage correction of tetralogy of Fallot associated with anomalous origin of the left pulmonary artery from the aorta and aortopulmonary window.

We report a rare case of tetralogy of Fallot associated with anomalous origin of the left pulmonary artery from the aorta and aortopulmonary window. Successful one-stage total correction was performed under cardiopulmonary bypass, including implantation of the left pulmonary artery, repair of aortopulmonary window, and correction of tetralogy of Fallot. The patient experienced an uneventful postoperative course and was asymptomatic at one-year follow-up.

Host-Guest Intercalation Chemistry for the Synthesis and Modification of Two-Dimensional Transition Metal Dichalcogenides.

Intercalation chemistry is of great importance in solid-state physics and chemistry for the ability to modulate electronic structures for constructing new materials with exotic properties. This ancient and versatile discipline has recently become prevailing in the synthesis and regulation of 2D transition metal dichalcogenides (TMDs) with atomic thickness due to diverse host-guest configurations and their impact on layered frameworks, which bring in extensive applications in electronics, optoelectronics, and other energy-based devices. In order to prepare 2D TMD materials with desired structure and properties, it is essential to gain in-depth understanding of the key role the intercalation chemistry plays in the preparation process. A focused review on recent advances regarding 2D TMD materials through intercalation exfoliation from the view of host, guest, and solvent interactions is provided. The effect of intercalation chemistry on TMD nanosheets synthesis and modification is comprehensively reviewed. The interactions between host and guest from the aspects of lattice strain, interlayer distance, and carrier density are considered. Finally, a prospectus of the future research opportunities for the intercalation chemistry of 2D materials is provided.

Development of a primary reference material of natural C-reactive protein: verification of its natural pentameric structure and certification by two isotope dilution mass spectrometry.

C-reactive protein (CRP) is one of the most commonly used biomarkers for inflammation. The standardisation of a procedure for the detection of CRP has attracted significant attention globally, and primary reference materials of CRP based on the recombinant expression of E. coli that exist in the form of monomers have been developed. However, a primary reference material of natural CRP is still required to achieve the exact matching of CRP measurements in secondary reference materials (e.g. CRP in frozen human serum). Herein, the development process for a certified reference material of natural CRP is reported, namely GBW09228. The raw material employed in this study was CRP extracted and purified from human body fluid, and exhibits a natural and verified pentameric structure. Through the use of amino acid analysis isotope dilution mass spectrometry (AAA-IDMS) and signature peptide-IDMS, this reference material was certified, and its certification results can be traced to SI units. The developed method was evaluated for its accuracy using the international comparison tests of the National Metrology Institute of Japan (NMIJ) and the Korea Research Institute of Standards and Science (KRISS). Overall, a CRP primary certified reference material (CRM) of well-characterised purity was determined that could be used to calibrate an IDMS-based reference method, that could then be used to assign target values to secondary CRMs. These secondary CRMs could in turn be used to calibrate and verify the accuracy of immunoassays, thereby giving a good foundation for establishing a complete traceability chain for CRP.

Transcatheter closure of postoperative residual ventricular septal defects using Amplatzer-type perimembranous VSD occluders.

OBJECTIVES: The reoperations of postoperative residual ventricular septal defects (VSDs) are associated with higher risks. Our aim is to assess the efficacy and safety of transcatheter closure of postoperative residual VSDs using perimembranous VSD occluders. METHODS: Twenty-one patients with residual VSDs underwent transcatheter closure in our center from January 2005 to January 2012. The study population consisted of 9 males and 12 females whose ages ranged from 1.9 to 54 years (median age, 8.7 years). Eighteen cases had perimembranous VSD repair previously, 3 cases had tetralogy of Fallot surgical treatment. All patients had signs of left ventricle volume overload (Qp/Qs ≥ 1.5). Two types of perimembranous VSD occluders, symmetric and asymmetric, were used in 14 and 7 cases, respectively. The diameter of residual VSDs ranged from 4-16 mm (mean, 7.8 mm). The waist size of occluders ranged from 6-18 mm. RESULTS: There were 0 deaths and 1 serious adverse event. Intravascular hemolysis occurred in 1 patient (4.8%), lasted for 7 days, and recovered with therapy. A trivial intraprosthetic residual shunt was observed in 2 patients (9.5%) after the procedure and 1 patient (4.8%) at 6 months. Two patients (9.5%) had transient left anterior hemiblock and recovered within the first week after the procedure. At the latest follow-up, no atrioventricular block and new-onset aortic regurgitation occurred. CONCLUSIONS: Transcatheter closure is a feasible and safe management option for patients with postoperative residual VSDs and obviates the need for a second surgery and cardiopulmonary bypass.