The time-dependent expression of FPR2 and ANXA1 in murine deep vein thrombosis model and its relation to thrombus age

Thrombus age determination in fatal venous thromboembolism cases is an important task for forensic pathologists. In this study, we investigated the time-dependent expressions of formyl peptide receptor 2 (FPR2) and Annexin A1 (ANXA1) in a stasis-induced deep vein thrombosis (DVT) murine model, with the aim of obtaining useful information for thrombus age timing. A total of 75 ICR mice were randomly classified into thrombosis group and control group. In thrombosis group, a DVT model was established by ligating the inferior vena cava (IVC) of mice, and thrombosed IVCs were harvested at 1, 3, 5, 7, 10, 14, and 21 days after modeling. In control group, IVCs without thrombosis were taken as control samples. The expressions of FPR2 and ANXA1 during thrombosis were detected using immunohistochemistry and double immunofluorescence staining. Their protein and mRNA levels in the samples were determined by Western blotting and quantitative real-time PCR. The results reveal that FPR2 was predominantly expressed by intrathrombotic neutrophils and macrophages. ANXA1 expression in the thrombi was mainly distributed in neutrophils, endothelial cells of neovessels, and fibroblastic cells. After thrombosis, the expressions of FPR2 and ANXA1 were time-dependently up-regulated. The percentage of FPR2-positive cells and the level of FPR2 protein significantly elevated at 1, 3, 5 and 7 days after IVC ligation as compared to those at 10, 14 and 21 days after ligation (p < 0.05). Moreover, the mRNA level of FPR2 were significantly higher at 5 days than that at the other post-ligation intervals (p < 0.05). Besides, the levels of ANXA1 mRNA and protein peaked at 10 and 14 days after ligation, respectively. A significant increase in the mRNA level of ANXA1 was found at 10 and 14 days as compared with that at the other post-ligation intervals (p < 0.01). Our findings suggest that FPR2 and ANXA1 are promising as useful markers for age estimation of venous thrombi.

Hydrogen-Bonded Organic Cocrystal-Encapsulated Perovskite Nanocrystals as Coreactant-Free Electrochemiluminescent Luminophore for the Detection of Uranium

Lead halide perovskite nanocrystals with excellent photophysical properties are promising electrochemiluminescence (ECL) candidates, but their poor stability greatly restricts ECL applications. Herein, hydrogen-bonded cocrystal-encapsulated CsPbBr3 perovskite nanocrystals (PeNCs@NHS-M) were synthesized by using PeNCs as nuclei for inducing the crystallization of melamine (M) and N-hydroxysuccinimide (NHS). The as-synthesized composite exhibits multiplicative ECL efficiencies (up to 24-fold that of PeNCs) without exogenous coreactants and with excellent stability in the aqueous phase. The enhanced stability can be attributed to the well-designed heterostructure of the PeNCs@NHS-M composite, which benefits from both moiety passivation and protection of the peripheral cocrystal matrix. Moreover, the heterostructure with covalent linkage facilitates charge transfer between PeNCs and NHS-M cocrystals, realizing effective ECL emission. Meanwhile, the NHS and M components act as coreactants for PeNCs, shortening the electron-transport distance and resulting in a significant increase in the ECL signal. Furthermore, by taking advantage of the specific binding effect between NHS-M and uranyl (UO22+), an ECL system with both a low detection limit (1 nM) and high selectivity for monitoring UO22+ in mining wastewater is established. The presence of UO22+ disrupted the charge-transfer effect within PeNCs@NHS-M, weakening the ECL signals. This work provides an efficient design strategy for obtaining stable and efficient ECLs from perovskite nanocrystals, offering a new perspective for the discovery and application of perovskite-based ECL systems.

Hydrogen-Bonded Cocrystals Encapsulating CsPbBr3 Perovskite Nanocrystals with Enhancement of Charge Transport for Photocatalytic Reduction of Uranium

At present, poor stability and carrier transfer efficiency are the main problems that limit the development of perovskite-based photoelectric technologies. In this work, hydrogen-bonded cocrystal-coated perovskite composite (PeNCs@NHS-M) is easily obtained by inducing rapid crystallization of melamine (M) and N-hydroxysuccinimide (NHS) with PeNCs as the nuclei. The outer NHS-M cocrystal passivates the undercoordinated lead atoms by forming covalent bonds, thereby greatly reducing the trap density while maintaining good structure stability for perovskite nanocrystals. Moreover, benefiting from the interfacial covalent band linkage and long-range ordered structures of cocrystals, the charge transfer efficiency is effectively enhanced and PeNCs@NHS-M displays superior photoelectric performance. Based on the excellent photoelectric performance and abundant active sites of PeNCs@NHS-M, photocatalytic reduction of uranium is realized. PeNCs@NHS-M exhibits U(VI) reduction removal capability of up to 810.1 mg g-1 in the presence of light. The strategy of cocrystals trapping perovskite nanocrystals provides a simple synthesis method for composites and opens up a new idea for simultaneously improving the stability and photovoltaic performance of perovskite.

[Analysis of gene characteristics and core genome characteristics of carbapenem-resistant Enterobacter cloacae in rural residents of Weifang City, Shandong Province]

Objective: To investigate the drug-resistant gene characteristics and core genome characteristics of carbapenem-resistant Enterobacter cloacae (CR-ECL) in rural residents of Weifang City, Shandong Province. Methods: Fecal samples were collected from rural community residents in Weifang City, Shandong Province in 2017. Drug-resistant strains were screened using a carbapenem-resistant enterobacter chromogenic medium. CR-ECL positive strains were acquired via Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry(MALDI-TOFMS) analysis. The antibiotic resistance phenotype of CR-ECL was determined using a microbroth dilution assay. Whole genome sequencing (WGS) and analysis were conducted, along with an examination of the immediate vicinity of the blaNDM gene and phylogenetic analysis of the strains. Results: A total of 628 fecal samples were collected and tested, of which 6 were CR-ECL positive (detection rate 0.96%), all exhibiting multiple drug resistance (MDR) phenotypes. Six CR-ECL strains had four MLST genotypes (ST), all of which carried multiple drug resistance genes (blaNDM-1, blaNDM-5, etc.) and virulence genes (acrA, acrB, entB, fepC, etc.). There were mobile genetic elements ISAba125, TN3-IS3000, TN3 and IS5 in the genetic environment surrounding the blaNDM gene. The phylogenetic tree showed that the multi-locus sequence typing of the core genome (cgMLST) was consistent with the single nucleotide polymorphism (SNPs) results. The cgMLST results showed that the allele differences between strains 2BC0101B and 2BC0251B, 2BG0561B and 2BI0221B were 2 and 1, respectively. The SNPs results showed that the above two pairs of bacteria also clustered together. It was found that the strains of chicken fecal samples in the National Center for Biotechnology Information (NCBI) database were located in the center of the evolutionary tree, and the local sequences could be traced back to American human sequences. Conclusion: Multidrug-resistant CR-ECL is detected in rural community residents in Weifang City, Shandong Province.

Flexible three-dimensional covalent organic frameworks for ultra-fast and selective extraction of uranium via hydrophilic engineering

It has been considered challenging to develop ideal adsorbents for efficient and lower adsorption time uranium extraction, especially 3D covalent organic frameworks with interpenetrating topologies and tunable porous structures. Here, a "soft" three-dimensional (3D) covalent organic framework (TAM-DHBD) with a fivefold interpenetrating structure is prepared as a novel porous platform for the efficient extraction of radioactive uranium. The resultant TAM-DHBD appears exceptional crystallinity, prominent porosity and excellent chemical stability. Based on the strong mutual coordination between phenolic-hydroxyl/imine-N on the main chain and uranium, TAM-DHBD can effectively avert the competition of other ions, showing high selectivity for uranium extraction. Impressively, the 3D ultra-hydrophilic transport channels and multi-directional uniform pore structure of TAM-DHBD lay the foundation for the ultra-high-speed diffusion of uranium (the adsorption equilibrium can be reached within 60 min under a high-concentration environment). Furthermore, the utilization of lightweight structure not only increases the adsorption site density, but renders the adsorption process flexible, achieving a breakthrough adsorption capacity of 1263.8 mg g^-1. This work not only highlights new opportunities for designing microporous 3D COFs, but paves the way for the practical application of 3D COFs for uranium adsorption.

An ionic vinylene-linked three-dimensional covalent organic framework for selective and efficient trapping of ReO4- or 99TcO4. Nat Commun 2022;13:7621. [PMID: 36494388 PMCID: PMC9734744 DOI: 10.1038/s41467-022-35435-7]

The synthesis of ionic olefin linked three-dimensional covalent organic frameworks (3D COFs) is greatly challenging given the hardness of the formation of stable carbon-carbon double bonds (-C = C-). Herein, we report a general strategy for designing porous positively charged sp² carbon-linked 3D COFs through the Aldol condensation promoted by quaternization. The obtained 3D COFs, namely TFPM-PZI and TAPM-PZI, showed impressive chemical stability. Furthermore, the positively charged frameworks with regular porosity endow 3D ionic COFs with selective capture radioactive ReO₄^-/TcO₄^- and great removal efficiency in simulated Hanford waste. This research not only broadens the category of 3D COFs but also promotes the application of COFs as efficient functional materials.

3D Ionic Olefin-Linked Conjugated Microporous Polymers for Selective Detection and Removal of TcO4-/ReO4- from Wastewater

Technetium (⁹⁹Tc) is a highly toxic radioactive nuclear wastewater contaminant. Real-time detection of ⁹⁹Tc is very difficult due to its difficult-to-complex nature. Herein, a novel three-dimensional ionic olefin-linked conjugated microporous polymer (TFPM-EP-Br) is constructed using tetrakis(4-aldehyde phenyl)methane (TFPM) as the central monomer. The unique cationic cavity and highly hydrophobic framework enable TFPM-EP-Br to act as a fluorescent sensor for TcO₄^-. The fluorophores of TFPM-EP-Br can be quenched due to electron transfer from TFPM-EP-Br to TcO₄^- and the formation of strongly nonfluorescent complexes. Meanwhile, the regular pore channels are beneficial for the fast mass transfer of TcO₄^-, resulting in an ultrafast response time (less than 2 s) with an ultralow detection limit (33.3 nM). In addition, the ultrahigh specific surface area enables TFPM-EP-Br to combine the ability to synergistically detect and remove radioactive ⁹⁹Tc. From this perspective, the novel conjugated microporous polymer has made a breakthrough in the detection and extraction of radioactive contaminants.

[Impact Mechanisms of Carboxyl Group Modified Cathode on Acetate Production in Microbial Electrosynthesis Systems]

Microbial electrosynthesis systems (MESs) can convert carbon dioxide into added value compounds using microorganisms as catalyst, which is expected to help achieve conversion of greenhouse gases into resources. However, the synthetic efficiency of MESs is far behind the industry requirements. In this study, carbon cloth surfaces were bonded with carboxyl groups by electrochemical reduction of aryl diazonium salts and then used as a cathode in MESs reactors. The results showed that the hydrophilicity of the carbon cloth surfaces improved after the carboxyl groups were modified. However, weaker current of cyclic voltammetry was obtained in the modified cathode. Significant differences were observed between modified (CA-H, CA-M, CA-L) and non-modified cathode (CK) during the start-up period. After 48h, the hydrogen production rate of CA-H, CA-M, CA-L was 21.45, 28.60, and 22.75 times higher than CK. After 120h, the acetate accumulation concentration of CA-H, CA-M, CA-L was 2.01, 2.43, and 1.44 times higher than CK. After 324h, there was little difference in the electrochemical activity of cathodic biofilm and protein content (about 0.47 mg·cm^-2) in all groups. The analysis of the community structure of cathodic biofilm showed that, in the genus level, Acetobacterium, Norank_p_Saccharibacteria, and Thioclava were the dominant species, accounting for 59.6% to 82.1%. There was little difference in the relative abundance of Acetobacterium in all groups (31.3% to 40.1%). However, the relative abundance of norank_p_Saccharibacteria in CA-H, CA-M, CA-L, and CK were 16.1%, 24.6%, 31.1%, and 37.5%, respectively. The carboxyl modified cathode had a great influence on the start-up stage of MESs, which could be a new idea for the rapid start-up of MESs.

[Expression of integrin αvβ3, CXC chemokine receptor 4 and CXC chemokine receptor 7 and their relationship with lymph node metastasis in squamous cell carcinoma of head and neck]

Objective: To investigate the expression of integrin αvβ3, CXC chemokine receptor (CXCR)4 and CXCR7 and their relationship with lymph node metastasis in squamous cell carcinoma of head and neck (SCCHN). Methods: The expression of integrin αvβ3, CXCR4 and CXCR7 was detected by immunohistochemistry SABC in 92 cases of primary SCCHN, metastatic lymph node, normal oral mucosa tissues and normal lymph nodes. Results: The positive rate of the expression of integrin αvβ3, CXCR4 and CXCR7 was 75% (69/92), 81%(75/92) and 76%(70/92), respectively in primary SCCHN, and was 82%(75/92), 76%(70/92) and 65%(60/92), respectively in metastatic lymph node. The expression of integrin αvβ3 and CXCR4 in primary SCCHN (r=0.813, P<0.05) and lymph node metastasis (r=0.541, P<0.05) was positively correlated. Integrin αvβ3 and CXCR7 expression in primary SCCHN (r=0.683, P<0.05) and lymph node metastasis (r=0.708, P<0.05) was positively correlated. CXCR4 and CXCR7 expression in primary SCCHN (r=0.644, P<0.05) and lymph node metastasis (r=0.707, P<0.05) had a positive correlation. The expression level was associated with tumor size (P=0.040, 0.001, 0.009), lymph node metastasis (P=0.001, 0.000, 0.000) and surrounding tissue invasion (P=0.046, 0.002, 0.001), but not related to age (P=0.097, 0.274, 0.162), gender (P=0.103, 0.309, 0.187). Conclusions: The overexpression of integrin αvβ3, CXCR4 and CXCR7 in primary head and neck squamous carcinoma and metastatic lymph nodes was related to lymph node metastasis. The co-expression of integrin αvβ3, CXCR4 and CXCR7 may play a synergistic role in lymphatic metastasis of SCCHN.

[Design of the system for detecting impedance cardiography based on windows plantform]

In this paper is introduced systematically the design of the system for detecting impedance cardiography (ICG) based on Windows plantform. The three major ICG indexes of 30 students have been detected by the designed system in the clinical application, and conform with the results from the reference. On the other hand, compared with the system based on DOS plantform, the system has higher detection speed, and becomes more convenient, more flexible by the introduction of Mouse.

Survival of implanted fetal dopamine cells and neurologic improvement 12 to 46 months after transplantation for Parkinson's disease

BACKGROUND AND METHODS

Patients with Parkinson's disease tend to have a reduced response to levodopa after 5 to 20 years of therapy, with "on-off" fluctuations consisting of dyskinesia alternating with immobility. In an effort to modify the motor disability of advanced Parkinson's disease, we implanted embryonic mesencephalic tissue containing dopamine cells into the caudate and putamen of seven patients. Two patients received unilateral grafts in the caudate and the putamen on the side opposite the side with worse symptoms. Five patients received bilateral grafts implanted in the putamen only. In six of the seven patients, the fetal tissue was obtained from a single embryo with a gestational age of seven to eight weeks. The tissue was injected by means of 10 to 14 needle passes. There were no surgical complications. Four of the seven patients underwent immunosuppression with cyclosporine and prednisone.

RESULTS

All patients reported improvement according to the Activities of Daily Living Scale when in the on state 3 to 12 months after surgery (P < 0.01). Neurologic examination according to the Unified Disease Rating Scale showed that five of the seven patients improved when in the on state six months after surgery. The mean group Hoehn-Yahr score improved from 3.71 to 2.50 (P < 0.01). Computer and videotape testing in the home supported these findings. Fluctuations in clinical state were moderated, and periods of dyskinesia and off episodes were shorter and less severe than before implantation. Drug doses were reduced by an average of 39 percent (P < 0.01; maximum, 58 percent). The results of clinical evaluation and fluorodopa positron-emission tomography in one patient were compatible with transplant survival for as long as 46 months. Both immunosuppressed and nonimmunosuppressed patients improved.

CONCLUSIONS

Fetal-tissue implants appear to offer long-term clinical benefit to some patients with advanced Parkinson's disease.