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Abstract Background Spontaneous bacterial peritonitis (SBP) is a common complication in patients with cirrhosis. The diagnosis of SBP is still mostly based on ascites cultures and absolute ascites polymorphonuclear (PMN) cell count, which restricts the widely application in clinical settings. This study aimed to identify reliable and easy-to-use biomarkers for both diagnosis and prognosis of cirrhotic patients with SBP. Methods We conducted a retrospective study including 413 cirrhotic patients from March 2013 to July 2022 in the First Affiliated Hospital of Guangxi Medical University. Patients’ clinical characteristics and laboratory indices were collected and analyzed. Two machine learning methods (Xgboost and LASSO algorithms) and a logistic regression analysis were adopted to screen and validate the indices associated with the risk of SBP. A predictive model was constructed and validated using the estimated area under curve (AUC). The indices related to the survival of cirrhotic patients were also analyzed. Results A total of 413 cirrhotic patients were enrolled in the study, of whom 329 were decompensated and 84 were compensated. 52 patients complicated and patients with SBP had a poorer Child–Pugh score (P

Objective This study aimed to examine the mechanism of hyperphosphatemia-induced vascular calcification (HPVC). Methods Primary human aortic smooth muscle cells and rat aortic rings were cultured in Dulbecco’s modified Eagle’s medium supplemented with 0.9 mM or 2.5 mM phosphorus concentrations. Type III sodium-dependent phosphate cotransporter-1 (Pit-1) small interfering RNA and phosphonoformic acid (PFA), a Pit-1 inhibitor, were used to investigate the effects and mechanisms of Pit-1 on HPVC. Calcium content shown by Alizarin red staining, expression levels of Pit-1, and characteristic molecules for phenotypic transition of vascular smooth muscle cells were examined. Results Hyperphosphatemia induced the upregulation of Pit-1 expression, facilitated phenotypic transition of vascular smooth muscle cells, and led to HPVC in cellular and organ models. Treatment with Pit-1 small interfering RNA or PFA significantly inhibited Pit-1 expression, suppressed phenotypic transition, and attenuated HPVC. Conclusions Our findings suggest that Pit-1 plays a pivotal role in the development of HPVC. The use of PFA as a Pit-1 inhibitor has the potential for therapeutic intervention in patients with HPVC. However, further rigorous clinical investigations are required to ensure the safety and efficacy of PFA before it can be considered for widespread implementation in clinical practice.

Abstract Background Single-cell RNA sequencing (scRNA-seq) provides a powerful tool to capture transcriptomes at single-cell resolution. However, dropout events distort the gene expression levels and underlying biological signals, misleading the downstream analysis of scRNA-seq data. Results We develop a statistical model-based multidimensional imputation algorithm, scMTD, that identifies local cell neighbors and specific gene co-expression networks based on the pseudo-time of cells, leveraging information on cell-level, gene-level, and transcriptome dynamic to recover scRNA-seq data. Compared with the state-of-the-art imputation methods through several real-data-based analytical experiments, scMTD effectively recovers biological signals of transcriptomes and consistently outperforms the other algorithms in improving FISH validation, trajectory inference, differential expression analysis, clustering analysis, and identification of cell types. Conclusions scMTD maintains the gene expression characteristics, enhances the clustering of cell subpopulations, assists the study of gene expression dynamics, contributes to the discovery of rare cell types, and applies to both UMI-based and non-UMI-based data. Overall, scMTD’s reliability, applicability, and scalability make it a promising imputation approach for scRNA-seq data.

Carbon nanotubes (CNTs) have high strength and stable chemical properties, offering the potential to enhance the mechanical performance of cementitious grouting materials and finding wide applications in the field. This paper reviews the recent research on the application of CNTs in cementitious grouting materials. It introduces the basic structure of CNTs and commonly used dispersion methods in cementitious grouting materials, analyzing and summarizing hydration and microstructure, mechanical properties, and early shrinkage performance of carbon nanotubes-cementitious grouting materials, highlighting current research challenges. Additionally, the future research on CNTs in cementitious grouting materials is also envisioned. [ABSTRACT FROM AUTHOR]

Aims: Carbapenem-resistant K. pneumoniae (CRKP) is the most common carbapenem-resistant Enterobacteriaceae with high mortality. Ceftazidime-avibactam (CAZ-AVI) has exhibited excellent in vitro activity in vivo against CRKP. However, the efficacy of CAZ-AVI in KPC-producing CRKP-infected patients with different kidney statuses varies, such as renal insufficiency, normal renal function, and augmented renal clearance (ARC). We explored the use of therapeutic drug monitoring (TDM) to evaluate the concentration and efficacy of CAZ-AVI in CRKP-infected patients with different kidney statuses.Methods: Serum concentrations for CAZ and AVI were determined by the high-performance liquid chromatography method. Bacterial identification, routine susceptibility testing, renal function index, and others were performed in standard protocols in the hospital’s clinical laboratories.Results: In the two patients with ARC, in case 1, CAZ-AVI 2.5g q6h was used with good efficacy, and the concentrations were up to the pharmacokinetics/pharmacodynamics targets. In Case 2, 2.5 g q8h was used with invalid effectiveness, and AVI Cmin was only 0.797 mg/l, which is lower than the PK/PD target. Case 3 was renal insufficiency using CAZ-AVI 1.25 q8h, and case 4 was normal renal function using 2.5 g q8h. Their concentrations were both up to the PK/PD targets.Conclusion: TDM results demonstrated that CAZ-AVI steady-state plasma concentration varies among patients with different kidney statuses, providing evidence for the utility of TDM of CAZ-AVI in individualized drug dose adjustment. ARC patients may need more CAZ-AVI daily doses than the standard dose.

Purpose: The association between serum uric acid (SUA) and atrial fibrillation (AF) has been widely focused on and studied in recent years. However, the exact association between SUA and AF is unclear, and the effect of gender on the association between SUA levels and AF has been controversial. This study aimed to investigate the association between SUA levels and non-valvular AF (NVAF) and the potential effect of gender on it. Patients and Methods: A total of 866 NVAF patients (463 males, age 69.44 ± 8.07 years) and 646 sex-matched control patients in sinus rhythm, with no history of arrhythmia were included in this study. t-test, ANOVA, and chi-square test were used for baseline data analysis. The receiver operating characteristic curve, logistic regression and Pearson correlation analysis were used for correlation analysis. Results: Compared to controls, NVAF patients exhibited higher SUA (P< 0.001). After adjusting for confounders of NVAF, SUA remained significantly associated with NVAF, regardless of gender (OR= 1.31, 95% CI 1.18– 1.43, P< 0.001). SUA demonstrated higher predictability and sensitivity in predicting the occurrence of female NVAF compared to male (area under the curve was 0.68 (95% CI 0.64– 0.72, P< 0.001), sensitivity 87.3%), with the optimal cut-off point identified as 5.72 mg/dL. Furthermore, SUA levels correlated with APOA1, Scr and NT-proBNP in NVAF patients. SUA levels varied significantly among NVAF subtypes. Conclusion: High SUA levels were independently associated with NVAF, regardless of gender. SUA exhibited higher predictability and sensitivity in predicting the occurrence of NVAF in females compared to males. High SUA levels may affect other NVAF-related factors and participate in the pathophysiological process of NVAF. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) nanorods were synthesized by hydrothermal process using anhydrous CaCl2 and (NH4)2HPO4 as raw materials, urea was used as a homogeneous precipitation agent; hexadecyltrimethy ammonium bromide (CTAB) was used as a template agent. Phase composition and microstructure of the products were characterized via X-ray diffractometer (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The results show that the morphologies of HA nanorods can be controllably fine-tuning by changing the reaction temperature and time. Hexagonal single crystal HA nanorods single structure can be obtained at 120℃ for hydrothermal 12 h, its length is about 0.5-1.0 μm, diameter is about 15-30 nm. Finally, the role of CTAB was studied by the formation process of nanorods crystalline structure in details, and verified by experiment.

BACKGROUND Black shale series is an important carrier of many useful elements. Cu, Pb, Zn, Ni, Mo, V, U, Au, Ag, rare and REE elements were abnormally enriched in the black rock series. The noble metal elements (PGE, Au, Ag) in some black shale series are also anomalously enriched, even partially exceeding the basic and ultrabasic rocks. However, the occurrence of PGE in such black shale series is still an unsolved problem. OBJECTIVES In order to clarify the occurrence of noble metal elements, Mo-Ni deposits in the black shale of the Niutitang Formation of the Cambrian system in Zhangjiajie, Hunan Province, were collected as research samples. METHODS The heavy placer classification, chemical analysis, X-ray diffraction analysis, scanning electron microscopy and energy disperse spectroscopy were used to study the occurrence of noble metal elements. RESULTS Chemical analysis showed that:Pt 531×10-9, Pd 514×10-9, Os 185×10-9, PGEs 1259.43×10-9, Au 332×10-9, Ag 12.2×10-6. These precious metals were concentration in ore-formation. CONCLUSIONS 1) Silver exists mainly as independent minerals, a small amount exist as isomorphism in other minerals. Independent minerals include:novakite, polybasite, andorite, dyscrasite, canfieldite, marrite, hocartite, argentite, Ag-Sn-Sb intergrowth compounds. The isomorphism is mainly freibergite-Ag-tennantite, silver-bearing galena and silver-bearing domeykite. 2) Native gold doesn't exist as independent mineral and is also not adsorbed by carbon. Meanwhile, pyrite was an important gold-bearing mineral. 3) PGEs do not exist as independent minerals and are no longer enrichment in different classification sample. It is speculated that PGE minerals are likely to exist in nanometer form. It is suggested that the application of nanomaterials can be considered in the future study of mineral processing.

Multiple sclerosis (MS) is a chronic fatal central nervous system (CNS) disease involving in complex immunity dysfunction. Recently, long noncoding RNAs (lncRNAs) were discovered as the important regulatory factors for the pathogenesis of MS. However, these findings often cannot be repeated and confirmed by the subsequent studies. We considered that the small-scale samples or the heterogeneity among various tissues may result in the divergence of the results. Currently, RNA-seq has become a powerful approach to quantify the abundances of lncRNA transcripts. Therefore, we comprehensively collected the MS-related RNA-seq data from a variety of previous studies, and integrated these data using an expression-based meta-analysis to identify the differentially expressed lncRNA between MS patients and controls in whole samples and subgroups. Then, we performed the Jensen-Shannon (JS) divergence and cluster analysis to explore the heterogeneity and expression specificity among various tissues. Finally, we investigated the potential function of identified lncRNAs for MS using weighted gene co-expression network analysis (WGCNA) and gene set enrichment analysis (GSEA), and 5,420 MS-related lncRNAs specifically expressed in the brain tissue were identified. The subgroup analysis found a small heterogeneity of the lncRNA expression profiles between brain and blood tissues. The results of WGCNA and GSEA showed that a potential important function of lncRNAs in MS may be involved in the regulation of ribonucleoproteins and tumor necrosis factor cytokines receptors. In summary, this study provided a strategy to explore disease-related lncRNAs on genome-wide scale, and our findings will be benefit to improve the understanding of MS pathogenesis.

The Huili Pt-Pd deposit in Sichuan Province is an independent platinum element ore deposit. In some ore sections, the contents of Pt and Pd have reached industrial grade. It is necessary to understand the occurrence of platinum group elements and characteristics of platinum group minerals. However, due to the low-grade platinum group elements (PGEs) in raw ore, chemical analysis is an indirect research method for the occurrence of platinum group elements, and the conclusion is thus not complete. Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS) were used to observe the inbuilt state, particle size, morphology characteristics, and the occurrence of the platinum group minerals. Results show that the PGEs in the deposit are mainly composed of pure Pt and Pd. The contents of Rh, Ir, Ru, and Os are very low, and the independent minerals composed of these four elements are undetected. Pt and Pd can exist in the form of simple substance elements and compounds with As, Te, Sb, Bi. There were 17 kinds of platinum group minerals, including Pt, As-Pt, As-Pd-Pt/As-Pt-Pd, and Pd-Pt-Cu/Pt-Pd-Cu. The pure Pt and the remaining Pt group minerals are found locally. The platinum group minerals have two kinds of inbuilt states, wrapped (52.39%) and intergranular (47.62%). Crystals of platinum group minerals are mainly xenomorphic granular, 1.36-32.7 μm, with a large range of particle sizes. The micropore structure, grapy structure and girdle zone can be found in some mineral crystals. The contact mode is mainly curve contact, followed by linear contact. These results provide a scientific basis for the platinum group minerals in beneficiation-metallurgy and resource evaluation.

Hydroxyapatite (HAp) is coassembled with many organic molecular templates led by collagens in natural bone. In this study, it is presumed that small intestinal submucosa (SIS) with acetamide group chelates calcium ion and bacterial cellulose (BC) has strong intermolecular hydroxyl group and powerful attraction for calcium ion to initiate initial nucleation. Phosphate ions bind calcium ions to form seed crystal of calcium phosphate, which is further directionally grown under the mediation of the template structure and finally forms weakly crystalline HAp, providing an environment for the HAp formation. Besides, the samples are characterized by X‐ray diffraction, Fourier transform infrared, X‐ray photoelectron spectroscopy, scanning electron microscope, and transmission electron microscope to unveil the phase structure, composition, and morphology, and a growth mechanism is proposed. HAp is successfully synthesized on SIS–BC biomineralization template. The results show morphology of samples from sheet‐lamellar‐like to flower‐like or porous‐spheroid‐like from 1 day to 7 days. The plate‐like HAp rods are polycrystal with c‐axis orientation. Interestingly, the HAp/SIS‐BC composites have the least relative mass of HAp on mineralization and the content of HAp (57%) is very close to the human bone tissue in structure (about 60%). Finally, the HAp mineralized films show good biocompatibility through MC3T3‐E1cells test for the potential biomaterials. [ABSTRACT FROM AUTHOR]

Micro-blog data has the characteristic of real-time,volume,short-text,and noise-rich.So it is a challenge for the traditional topic detection technology.A novel micro-blog topic detection algorithm based on topic model was proposed.Firstly,the micro-blog data was expressed as text word matrix and word relation matrix.The topic word was extracted from the two vectors.Secondly,the topic model was obtained with clustering.Finally,the topic detection of micro-blog was obtained by clustering text and topic model.Experimental results show that the algorithm proposed can effectively detection the text topic,and with the best parameter group of precision,recall rate,F,and the value F is about 95%.

To improve the storage stability of glutamic acid decarboxylase (GAD), superparamagnetic magnetite (Fe3O4) nanoparticles were synthesized by co-precipitation method and coated with polydopamine (PDA) for GAD immobilization. Dynamic light scattering and transmission electron microscopy were used to determine size of the nanoparticles, which were approximately 10 nm, increasing to 15 nm after PDA-coating and to 20 nm upon GAD binding. Vibrational scanning measurements significantly represented the superparamagnetic behavior of the Fe3O4, and X-ray diffraction analysis confirmed that the crystalline structure before and after coating with PDA and the further immobilization of GAD remained the same. Thermogravimetric analysis and Fourier-transform infrared spectroscopy proved that the PDA-coating on Fe3O4 and further immobilization of GAD were successful. After immobilization, the enzyme can be used with a relative specific activity of 40.7% after five successive uses. The immobilized enzyme retained relative specific activity of about 50.5% after 15 days of storage at 4 °C, while free enzyme showed no relative specific activity after two days of storage. The GAD immobilization on PDA-coated magnetite nanoparticles was reported for the improvement of enzyme storage stability for the first time.

The Tangjiaping molybdenum deposit, discovered in 2006, is a large-scale porphyry molybdenum deposit. The studies of its basic geological work and metallogenic regularity have been completed by previous researchers with conventional geological methods. The results showed that the Tangjiaping molybdenum deposit belongs to the plutonic hypabyssal porphyry molybdenum deposit and the Tangjiaping granodiorite porphyry molybdenum mineralization acts as a mother rock mining area. However, there is no proof that the metallogenic regularity is from the perspective of mineralogy. From the mineralogy angle four kinds of typomorphic characteristics (chemical composition, trace elements, crystal structure, lattice parameters, structure etc.) of molybdenite, pyrite, quartz, and feldspar from the Tangjiaping molybdenum mine were studied using the separation of single mineral to chemical analysis, X-ray Diffraction and rock mineral identification technology. The results are: ① the mining area of molybdenite is 2H type, and the content of Re component is very low; the δ34S of molybdenite values is 3.0‰; sulfur isotopic changes in a small range close to the meteorite sulfur with the characteristics of deep source sulfur, indicating that the sulphur is derived from the granite porphyry. ② pyrite is rich in trace elements Mo, Co, Cu, poor Ni, Pb, Zn, in addition, low content of Ag and Au, S/Se is greater than 250000, which is consistent with the 'S/Se more than 250000-500000 area could not find gold' conclusion. ③ quartz is rich in Mo. δ18O in mineralization quartz veins are lower, showing a small amount of precipitation appeared in the hydrothermal alteration during the later mineralization. ④ feldspar is rich in Mo. Light rare earth (La-Nd) content is higher than that of rare earth (Sm-Ho) content and heavy rare earth (Er-Y) content. Potassium feldspar degree of ordering, triclinic and structure parameter values were higher. Potassium feldspar structure at low temperature, shows that the potassium feldspar in this area is triclinic symmetry microcline at low temperature conditions, and it is the product of hydrothermal activity; rock potash feldspathization characteristics of molybdenum mineralization is the most favorable. The Tangjiaping molybdenum deposit therefore belongs to the plutonic hypabyssal porphyry molybdenum deposit, and this paper has important significance for the summarization of porphyry type molybdenum ore metallogenic regularity and prospecting marks.