Green and Fast Strategies for Energy-Efficient Preparation of the Covalent Organic Framework TpPa-1.

Three synthesis procedures for the covalent-organic framework (COF) TpPa-1 are studied with the purpose of setting up the most promising one in a fast and green way, leading to a more environmentally friendly and sustainable process. With conventional heating, good crystallinity and a high BET specific surface area (SSA) of up to 1007 m2 ⋅ g-1 are achieved at 170 °C for 3 days using water as the quintessential green solvent. However, the application of microwave radiation in the synthesis for this crystalline porous polymer allows reaction times to be shortened to 30 min while maintaining structural and textural properties (BET SSA of 928 m2 ⋅ g-1 ) and obtaining yields close to 98 % (vs. 90 % in the hydrothermal synthesis). The water-assisted mechanochemical synthesis is also an environmentally friendly synthetic approach; with heating at 170 °C in a two-step process (10+10 min), high crystallinity is achieved, a BET SSA of 960  m2 ⋅ g-1 and a yield of 98 % for TpPa-1.

Ocular syphilis on the rise: a 10-year analysis from 2010 to 2020.

PURPOSE: The purpose of the study was to evaluate the incidence of ocular syphilis as well as diagnostic parameters, comorbidities, and visual outcomes over a 10-year time period in West Virginia. METHODS: A retrospective chart review included 25 eyes of 17 patients with ocular syphilis between 2010 and 2020. RESULTS: The incidence of systemic syphilis at a large tertiary referral center has increased from 27 cases in 2010 to 105 cases in 2020. Seventeen patients were identified with ocular syphilis. Bilaterality was present in 47.1% of cases. In this study, 70.6% of patients were male and 29.4% were female. The median age of presentation was 40.2 years (range 21-63). Panuveitis was the most common (60.0%) followed by isolated anterior uveitis (16.0%), chorioretinitis (12.0%), inner retinitis (4.0%), and papillitis (8.0%). Forty percent of patients had visual acuity worse than 20/400 on presentation. Post-treatment visual acuity improved in all patients. Rapid plasma reagin (RPR) and Treponema pallidum particle agglutination (TP-PA) tests were positive in 84.6% and 100% of cases, respectively. CSF venereal disease research laboratory (VDRL) was positive in 36.4%, CSF pleocytosis was present in 72.7%, and elevated CSF protein was observed in 81.8%. Human immunodeficiency virus (HIV) co-infection was present in 31.3%. A majority of patients experienced maculopapular rash and/or history of genital chancre. The anatomic classification of presenting uveitis (anterior, intermediate, posterior, and panuveitis) did not correlate with clinical variables including age, gender, HIV status, serologic test, presence of rash, or year of diagnosis (p > 0.05). CONCLUSION: Ocular syphilis is becoming increasingly prevalent and can present with a variety of ocular findings; therefore, it should be considered in the differential diagnosis for patients with ocular inflammation. Visual prognosis is excellent with timely diagnosis and treatment.

Clinical prediction and diagnosis of neurosyphilis in HIV-negative patients: a case-control study.

BACKGROUND: Early diagnosis and treatment of neurosyphilis is of great significance for regression. There is no gold standard for the diagnosis of neurosyphilis. We did this study to explore the factors associated with the clinical diagnosis of neurosyphilis and assess their accuracy for the diagnosis of neurosyphilis. METHODS: We retrospectively reviewed 100 cases of syphilis patients who underwent lumbar puncture at a major dermatology hospital in Guangzhou, China between April 2013 and November 2016. Fifty patients who were clinically diagnosed with neurosyphilis were selected as case group. Control group consisted of 50 general syphilis patients who were matched with age and gender. The records of patients were reviewed to collect data of socio-demographic information, clinical symptom, and laboratory indicators. Multivariable logistic regression was used to explore diagnostic indictors, and ROC analysis was used to assess diagnostic accuracy. RESULTS: Neurological symptoms (odds ratio (OR) = 59.281, 95% CI:5.215-662.910, P = 0.001), cerebrospinal fluid (CSF) Treponema pallidum particle agglutination (TPPA) titer (OR = 1.004, 95% CI:1.002-1.006, P < 0.001), CSF protein (OR = 1.005, 95% CI:1.000-1.009, P = 0.041), and CSF white blood cell (WBC) (OR = 1.120, 95% CI:1.017-1.233, P = 0.021) were found to be statistically associated with neurosyphilis. In ROC analysis, CSF TPPA titer had a sensitivity of 90%, a specificity of 84%, and an area under curve (AUC) of 0.941. CONCLUSION: CSF TPPA can potentially be considered as an alternative test for diagnosis of neurosyphilis. Combining with neurological symptoms, CSF protein, CSF WBC, the diagnosis would have a higher sensitivity.

Evaluation of the BioPlex 2200 syphilis total screen (IgG/IgM) with reflex to an automated rapid plasma reagin test.

BACKGROUND: We evaluated the recently FDA cleared BioPlex 2200 Syphilis Total Screen and automated rapid plasma reagin (RPR) assay for the detection of total (IgG/IgM) treponemal and non-treponemal antibodies in the reverse syphilis algorithm. METHODS: Prospectively submitted samples (n = 885) were assayed by both the IgG/IgM BioPlex Syphilis Screen and the original IgG BioPlex Syphilis Screen. The IgG screen reactive samples were reflexed to traditional RPR, and IgG/IgM screen reactive samples were reflexed to the automated RPR. Nonreactive RPR samples were tested by the Treponemal Pallidum Particle Agglutination test (TP-PA). Additional samples were collected (n = 404 total samples) to directly compare the automated and traditional RPR assays with each other. RESULTS: The sensitivity and specificity of the IgG/IgM screen with automated RPR was 95.6% (95% confidence interval [CI] 87.0-99.1) and 99.6% (CI 99.2-99.8) while the sensitivity and specificity of the BioPlex IgG screen with traditional RPR was 97.8% (CI 89.1-99.9) and 99.3% (CI 98.8-99.4). The sensitivity and specificity of the BioPlex RPR compared with traditional RPR was 95.8% (CI 93.9-97.0) and 94.1% (CI 89.4-91.1) and 95.3% (CI 92.6-97.1). The mean of the titer differences between the BioPlex RPR and the traditional RPR was 1.0 ± 0.9 SD titers. CONCLUSION: The addition of the detection of treponemal IgM antibodies to the IgG/IgM screen did not significantly affect the sensitivity and specificity compared to the original IgG screen. However, the addition of the comparable BioPlex RPR assay to the instrumentation significantly reduces the overall labor of syphilis screening and confirmation.

Cerebral syphilitic gumma masquerading as cerebral metastatic tumors: case report.

A 45-year-old man was admitted with severe headache and left-sided weakness, which worsened over 1 week. Brain imaging revealed a small lesion close to the sagittal sinus in the right frontal lobe with severe perilesional edema and showed enhancement on both CT and MRI obtained with contrast. Serological findings were positive for toluidine red unheated serum test (TRUST) positivity and Treponema pallidum particle agglutination assay. The patient was first suspected of having a malignant brain tumor and subsequently received emergency craniotomy. Brain biopsy suggested a diagnosis of syphilitic cerebral gumma; meanwhile the postoperative CSF TRUST titer was positive, and the patient's improvement with high-dose intravenous aqueous crystalline penicillin further supported this etiology. Finally, the lesion on the right frontal lobe had disappeared during the follow-up imaging examination and the myodynamia of the left limbs gradually improved. The authors recommend that diagnostic penicillin treatment should be first implemented. When a patient's history, clinical manifestations, syphilis serology, CSF examination, and other physiological changes indicate a diagnosis of syphilitic cerebral gumma, there is no doubt that surgery should be performed in patients with acute intracranial hypertension, but unnecessary craniotomy should be avoided as far as possible.

Ambient temperature fabrication of a covalent organic framework from 1,3,5-triformylphloroglucinol and 1,4-phenylenediamine as a coating for use in open-tubular capillary electrochromatography of drugs and amino acids.

A covalent organic framework (COF) named TpPa-1 was designed and synthesized at ambient temperature by an ultrasound-assisted method from 1,3,5-triformylphloroglucinol (Tp) and 1,4-phenylenediamine (Pa-1). It was utilized as a stationary phase in open-tubular capillary electrochromatography (OT-CEC). The column was coated with TpPa-1 using a covalent bonding strategy. The coated capillary was characterized by morphology, crystallography, and mesoporous analysis to confirm the successful fabrication. The OT-CEC method was utilized for the analysis of tetracyclines, sulfonamides, cephalosporins and amino acids with high-resolution (Rs > 1.81) and good precision (RSD < 4.9%). It takes about 12 h from COF preparation to OT-CEC separation. Graphical abstract A covalent organic framework (COF) named TpPa-1 was synthesized at ambient temperature by an ultrasound-assisted method from 1,3,5-triformylphloroglucinol (Tp) and 1,4-phenylenediamine (Pa-1). COF-TpPa-1 modified capillary column was utilized for the analysis of tetracyclines, sulfonamides, cephalosporins and amino acids with high-resolution and good precision.

Covalent organic framework TpPa-1 as stationary phase for capillary electrochromatographic separation of drugs and food additives.

Because of unique properties like permanent porosity, low density and large surface area, covalent organic frameworks are attractive microporous materials as stationary phase for CEC. Among them, COF-TpPa-1 possesses extraordinary chemical stability and common features of covalent organic frameworks. So, COF-TpPa-1 could be a promising material as stationary phase to enhance separation selectivity and tolerate the acid or alkaline electrochromatographic separation conditions. Here, we report the preparation of COF-TpPa-1 modified capillary column by in situ growth for electrochromatographic separation. The immobilization of COF-TpPa-1 on the inner wall of capillary column was confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. The fabricated COF-TpPa-1 modified capillary column indicated good resolution for the separation of neutral analytes, nonsteroidal anti-inflammatory drugs and food additives in open-tubular CEC mode. Compared with bare capillary column, the COF-TpPa-1 modified capillary column improved separation selectivity remarkably for tested analytes, including hydrophobic, π-π and hydrogen bond interactions. Besides, the prepared capillary column showed excellent repeatability and stability. The intraday, interday and column-to-column relative standard deviations of migration time for neutral analytes were less than 3.54%. This work shows enamine-linked covalent organic frameworks have great potential as stationary phases in CEC.

Evaluation of three automated Treponema pallidum antibody assays for syphilis screening.

The accuracy of the test is critical for the syphilis serology diagnosis. This study aims to evaluate the values of the Elecsys syphilis assay, the Architect syphilis assay, and the Mindray syphilis assay, as syphilis screening tests for pregnant women and patients with syphilis or other diseases. A reverse algorithm was used for the syphilis serology diagnosis. Serum samples (n = 584) were tested with three automated screening assays. All reactive sera by one, two, or three screening assays were further analyzed with the tolulized red unheated serum test (TRUST). Inconsistent results were confirmed by the Treponema pallidum particle agglutination assay (TPPA). The final patient diagnosis was made according to the results of syphilis serology, clinical evidence, and past medical history. The sensitivity, specificity, accuracy, and kappa value of each assay were as follows: for the Elecsys syphilis assay, 100.0%, 98.5%, 98.6%, and 0.927, respectively; for the Architect syphilis assay: 100.0%, 94.5%, 95.0%, and 0.770; and for the Mindray syphilis assay: 100.0%, 97.0%, 97.3%, and 0.862. The McNemar test showed that there were significant differences in the performance between the Elecsys syphilis assay and the Architect syphilis assay (P < 0.001), and between the Mindray syphilis assay and the Architect syphilis assay (P = 0.001). Our study demonstrated that three automated Treponema pallidum antibody assays generally showed high sensitivities and specificities, and so, they are suitable for use in screening for syphilis. The performances of the Elecsys syphilis assay and the Mindray syphilis assay are superior to Architect syphilis assay.

Cerebrospinal Fluid Treponema pallidum Particle Agglutination Assay for Neurosyphilis Diagnosis.

Limited data suggest that the cerebrospinal fluid Treponema pallidum particle agglutination assay (CSF-TPPA) is sensitive and a CSF Treponema pallidum hemagglutination assay (CSF-TPHA) titer of ≥1:640 is specific for neurosyphilis diagnosis. CSF-TPPA reactivity and titer were determined for a convenience sample of 191 CSF samples from individuals enrolled in a study of CSF abnormalities in syphilis (training data set). The sensitivity of a reactive test and the specificity for reactivity at serial higher CSF dilutions were determined. Subsequently, CSF-TPPA reactivity at a 1:640 dilution was determined for all available samples from study participants enrolled after the last training sample was collected (validation data set, n = 380). Neurosyphilis was defined as (i) a reactive CSF Venereal Disease Research Laboratory test (CSF-VDRL), (ii) detection of T. pallidum in CSF by reverse transcriptase PCR, or (iii) new vision loss or hearing loss. In the training data set, the diagnostic sensitivities of a reactive CSF fluorescent treponemal antibody absorption test (CSF-FTA-ABS) and a reactive CSF-TPPA did not differ significantly (67 to 98% versus 76 to 95%). The specificity of a CSF-TPPA titer of ≥1:640 was significantly higher than that of lower dilutions and was not significantly different from that of CSF-VDRL. In the validation data set, the diagnostic specificity of a CSF-TPPA titer of ≥1:640 was high and did not differ significantly from that of CSF-VDRL (93 to 94% versus 90 to 91%). Ten CSF samples with a nonreactive CSF-VDRL had a CSF-TPPA titer of ≥1:640. If a CSF-TPPA titer of ≥1:640 was used in addition to a reactive CSF-VDRL, the number of neurosyphilis diagnoses would have increased from 47 to 57 (21.3%). A CSF-TPPA titer cutoff of ≥1:640 may be useful in identifying patients with neurosyphilis when CSF-VDRL is nonreactive.

Performance Evaluation of CLIA for Treponema Pallidum Specific Antibodies Detection in Comparison with ELISA.

OBJECTIVES: In this study we aimed to evaluate the performance effects of chemiluminescence assay (CLIA) for Treponema pallidum specific antibodies detection, and to compare T. pallidum specific antibodies detection accuracy between CLIA and ELISA with TPPA (T. pallidum particle agglutination assay) as a confirmatory test. METHODS: A total of 865 samples from suspected syphilis patients and preoperative patients were included, in which T. pallidum specific antibodies were simultaneously detected by CLIA and ELISA. Among them, 457 samples were determined by TPPA. RESULTS: All coefficients of variation (CVs) of ELISA in high-, median-, and low-level samples were more than 5% and the maximum CV was 54.39% in the low-level sample. CVs of CLIA in different-level samples were all below 5%. Among the three assays the Spearman correlation and Kappa coefficients were 0.771 (P ≤ 0.001) and 0.854 (P ≤ 0.001, CLIA vs. ELISA), 0.806 (P ≤ 0.001) and 0.897 (P ≤ 0.001, ELISA vs. TPPA), 0.937 (P ≤ 0.001) and 0.967 (P ≤ 0.001, CLIA vs. TPPA), respectively. The area under the receiver operating characteristic curve (AUC) of CLIA was higher than that of ELISA (0.994 vs. 0.989) with TPPA as the confirmatory test. In 18 discrepant samples the consistency rate between CLIA and TPPA was elevated compared with that between ELISA and TPPA (72.22% vs. 27.78%, P = 0.008). In gray zone, the consistency rate of CLIA with TPPA was higher than that of ELISA with TPPA (90.91% vs. 41.67%, P = 0.027). CONCLUSIONS: Compared with ELISA, CLIA is more reliable, sensitive and accurate to detect serum T. pallidum specific antibodies. In the future it may be an alternative test with higher sensitivity to ELISA.

Evaluation of a Rapid Immunochromatographic Treponemal Antibody Test Comparing the Treponema Pallidum Particle Agglutination Assay.

BACKGROUND: In addition to conventional tests, several methods for detection of treponema-specific antibodies in clinical settings have been recently introduced. We aim to comparatively evaluate a rapid immunochromatographic test (ICT) for Treponema pallidum specific antibody (SD Bioline Syphilis 3.0) and the T. pallidum particle agglutination (TPPA) assay. METHODS: In all, 132 serum samples from 78 syphilis patients and 54 syphilis-negative controls were analyzed. SD Bioline Syphilis 3.0 test (Standard Diagnostic, Inc., Yongin, Korea) was evaluated and compared to Serodia TPPA assay (Fujirebio, Inc., Tokyo, Japan). All discrepant results between the two assays were repeatedly tested and evaluated by the fluorescent treponemal antibody-absorption (FTA-ABS) assay. Test reproducibility and 95% limit of detection of SD Bioline Syphilis 3.0 were determined across three different lots for seven consecutive days in triplicate. Interference due to autoantibodies and pregnancy was also tested. RESULTS: Percent agreement between SD Bioline Syphilis 3.0 and TPPA assays was 99.2%. Sensitivity and specificity were 100%, respectively. In TPPA assay, test-to-test, day-to-day, and lot-to-lot variations were not identified until 1:320 titer (eightfold dilutions). There was no interference due to the presence of antinuclear antibodies or samples or pregnancy. CONCLUSIONS: Percent agreement of SD Syphilis 3.0 and TPPA was very good. Sensitivity and specificity were appropriate for T. pallidum antibody detection. Thus, a rapid ICT could be suitable for syphilis antibody detection.

Evaluation of the Tibial Plateau-Patella Angle (TPPA) in Dogs.

Estimating a dog's patellar position involves various methods, which categorize it as norma, alta (high), or baja (low). However, they require various calculations. We aimed to evaluate the clinical applicability of a new method, the tibial plateau-patella angle (TPPA). This could aid in planning patella luxation surgery, estimating the patella position after TPLO and various osteotomies. We conducted a two-step study: first, on 15 stifles without pathologies from nine canine cadavers, and second, using 100 patient X-rays from the archive. Three stifle angle positions (45 ± 5°, 90 ± 5°, and 135 ± 5°) and three weight groups (S, M, and L) were evaluated in the first part of this study. Based on these results, the second part of this study was conducted using 100 pathology-free radiographs at the optimal stifle angle (90 ± 5°) from the archive. All radiographs were measured by three observers with varying levels of experience. Our results indicate that the stifle angle significantly impacted the TPPA, whereby lower values were detected with higher stifle angles, which remained consistent within the weight groups. High inter- and intra-observer agreement was achieved. The physiological TPPA values ranged from 26.7° to 48.8°, remaining consistent within the various weight groups. Observer 3 in Group S exhibited a 20% (insignificant) deviation, possibly due to challenges in determining the caudal point of the tibial plateau. In contrast with humans, TPPA values in dogs are negatively correlated with stifle angles, independent of weight. Our reliable and reproducible protocol suggests the potential benefits of training on small-breed dogs stifles.

Highly sensitive and selective determination of uranyl ions based on Ag/Ag2O-COF composite SERS substrate.

Uranium is an essential nuclear material in civilian and military areas; however, its extensive application raises concerns about the potential safety issues in the fields of environmental protection and nuclear industry. In this study, we developed an Ag/Ag2O-COF (covalent-organic framework) composite SERS substrate to detect uranyl ions (UO22+) in environmental aqueous solutions. Herein, the strong SERS effect of uranyl adsorbed in Ag/Ag2O composite and the high adsorption efficiency of COF TpPa-1 were combined to realize the trace detection of uranyl ions. This method displayed a linear range of 10-8 mol L-1 to 10-6 mol L-1 with the detection limit of 8.9 × 10-10 mol L-1 for uranyl ions. Furthermore, common metal cations and oxo-ions hardly affected the SERS detection of uranyl, which is helpful for the trace analysis of uranyl in natural water samples. Although the proposed strategy is deployed for uranyl detection, the reusable and high-efficiency system may be expanded to trace detection of other substance with Raman activity.

All-in-one Janus covalent organic frameworks separator as fast Li nucleator and polysulfides catalyzer in lithium-sulfur batteries.

The shuttle effect, sluggish conversion kinetics, and uncontrollable lithium dendrites seriously hinder the practical application of lithium-sulfur (Li-S) batteries. Among many modified materials, covalent organic frameworks (COFs) stand out for their excellent ability to inhibit the shuttle effect, while their role in promoting lithium nucleation and catalyzing the conversion of sulfur species has been largely ignored. In this study, an integrated COF separator (TpPa@2400) is developed as a rapid lithium nucleator and sulfur species catalyst in fast-charging Li-S batteries. According to the adsorption energy and Bader charge results, Li atoms preferentially adsorb onto the surface of the TpPa@2400 separator, and the larger Bader charge value (0.52 |e|) of the TpPa@2400 separator also signifies faster lithium transport, promoting the nucleation of Li ions. Furthermore, density functional theory (DFT) theoretically demonstrates that the TpPa@2400 separator exhibits lower free energy for sulfur species interconversion. As a result, the TpPa@2400 separator enables the Li-Li symmetric cell with an extended cycle life of 6000 h at a current density/capacity of 10 mA cm-2/10 mAh cm-2. The Li-S battery assembled using the TpPa@2400 separator delivers a high capacity of 1636.4 mAh/g at 0.1C and a rapid sulfur species conversion capacity of 513.8 mAh/g at 2C.

Comparison of Treponema-specific immunoglobulin G (IgG) index with Treponema pallidum particle agglutination (TPPA) index for detection of intrathecal Treponema-specific antibody synthesis for serological diagnosis of neurosyphilis.

The determination of Treponema-specific intrathecal immunoglobulin synthesis with the Treponema pallidum particle agglutination (TPPA) index is a well-established method recommended in German guidelines for the diagnosis of neurosyphilis. However, the TPPA test is no longer available. The aim of this study was to evaluate whether the determination of a Treponema-specific immunoglobulin G (IgG) index can substitute the TPPA index. Serum and cerebrospinal fluid (CSF) samples from patients with confirmed (n=6) and probable (n=3) neurosyphilis as well as patients with adequately treated syphilis without neurosyphilis (n=4) were investigated. In addition to index calculation further CSF parameters were determined. The results of the Treponema IgG and the TPPA index were consistent in all patients with confirmed neurosyphilis and non-neurosyphilis patients. In two patients with probable neurosyphilis the IgG index appeared more plausible than the TPPA index when taking into account all available laboratory and clinical data of the patients. In conclusion, the determination of Treponema-specific intrathecal immunoglobulin synthesis with the IgG index appears to be a suitable alternative to the TPPA index.

Well-constructed a water stable Cu-BTC@TpPa-1 binary composite with excellent capture ability toward malachite green.

Adsorptive removal of dyes (e.g., malachite green (MG)) from wastewater using commercially available adsorbents is not significantly efficient. Metal-organic frameworks (MOFs) such as Cu-BTC is considered as an excellent adsorbent in adsorption-separation filed. However, the water instability of Cu-BTC restricts its potential utilization in dye wastewater purification. In this paper, we have developed a novel metal/covalent-organic frameworks (Cu-BTC@TpPa-1) binary composite by solvothermal method. This composite serves as a multifunctional platform for the effective removal of MG from water. This Cu-BTC@TpPa-1 obviously keeps structural integrity soaked in water for 7 days. And its heat resistant performance can achieve 360 °C because of the TpPa-1 protection, which is outdistance to that of Cu-BTC. The adsorbed capacity of MG over Cu-BTC@TpPa-1 is exceptionally high, with an uptake of up to 64.12 mg/g, which is superior compared to previous adsorbents, highlighting its superior adsorption capabilities. The adsorptive performance was controlled by the associative effects of Cu-BTC and TpPa-1 with an association effect of π-complexation and electrostatic attraction. The Cu-BTC@TpPa-1 might be a prospective adsorbent for MG capture from industrial wastewater.

Acquired syphilis with flat condyloma in a 3 year-old girl: A case report.

The incidence of syphilis in young children is very low, with acquired syphilis exceptionally rare. A 3 year-old girl presented to our service with a reddish-brown rash on the external genitals and perianal area. The rash had been apparent for a period of 1 week. The girl was asymptomatic and had no history of sexual contact. Syphilis was suspected and the Treponema pallidum particle agglutination test (TPPA) was found to be positive, as well as the rapid plasma regin ring card test (RPR), with a titer of 1:64. The girl was diagnosed with toddler acquired secondary syphilis. The girl was cured after three treatments with penicillin. This report points out the need for clinicians to be aware of nonsexually transmitted syphilis, acquired in daily life by children without a history of sexual contact.

Confirmation value of Western blotting in detecting anti-treponema pallidum specific antibodies with suspicious results.

BACKGROUND: Due to the inconsistent results of anti-treponema pallidum (TP) specific antibodies by enzyme-linked immunosorbent assay (ELISA) and Treponema pallidum granule agglutination assay (TPPA) in clinical work, there will be a certain proportion of false-positives and false-negatives depending on TPPA as confirmation results. This study aimed to evaluate the necessity of Western blotting (WB) in samples with inconsistent results in detecting anti-TP antibodies by ELISA and TPPA. METHODS: Specific anti-TP test results in our clinical laboratory were retrospectively analyzed. The specimens with a positive or a negative result, but with colored ELISA plates, were retested by TPPA. WB was used to confirm the suspicious results between ELISA and TPPA. The Chi-square test was used to analyze whether the difference was statistically significant. RESULTS: A total of 106,757 anti-TP specimens were screened by ELISA from August 2018 to December 2019; 3972 were retested by TPPA, and 3809 were positive by TPPA. ELISA and TPPA showed different results in 163 specimens. Among them, 29 specimens were negative and 134 were positive by ELISA; 76 were negative, 23 were positive, and 64 were "reserve" by TPPA; 93 were negative, 31 were positive, and 39 were suspicious by the WB confirmation test. Compared with WB, the difference in the results of ELISA and TPPA was statistically significant. CONCLUSIONS: TPPA is an effective retest method for anti-TP antibody detection. If the results of anti-TP antibodies by ELISA and TPPA are inconsistent, it is necessary to use WB for confirmation. Trial registration This retrospective analysis is in accordance with the ethical guidelines of China and approved by the second hospital of Jiaxing (jxey-2018048).

In situ synthesis of 2D/2D MXene-COF heterostructure anchored with Ag nanoparticles for enhancing Schottky photocatalytic antibacterial efficiency under visible light.

It is a major challenge to combine the advantages of two kinds of two-dimensional materials to construct a heterojunction and achieve efficient photocatalytic antifouling. In this work, we covalently connected two materials MXenes and covalent organic frameworks (COFs) through the Schiff base reaction and anchored Ag nanoparticles (NPs) to prepare a Ti3C2/TpPa-1/Ag composite material with high efficiency bactericidal properties. The covalent bonding between MXene and COF greatly improved the stability of the material. Ti3C2/TpPa-1/Ag composite showed an excellent antibacterial property against S. aureus and P. aeruginosa. The fluorescence spectra of Ti3C2/TpPa-1/Ag proved that the electron transfer channels formed between the ternary materials could greatly improve the efficiency of carrier separation and prolong the life of photogenerated carriers. Density functional theory calculations showed that the synergistic catalytic effect of Ag and Ti3C2 could greatly reduce the work function along the interface, and the built-in electric field between the layers drive carrier fast migration, which effectively improve the catalytic performance.