Cross-Modal Retrieval Between 13C NMR Spectra and Structures Based on Focused Libraries

Library matching by comparing carbon-13 nuclear magnetic resonance (13C NMR) spectra with spectral data in the library is a crucial method for compound identification. In our previous paper, we introduced a deep contrastive learning system called CReSS, which used a library that contained more structures. However, CReSS has two limitations: there were no unknown structures in the library, and a redundant library reduces the structure-elucidation accuracy. Herein, we replaced the oversize traditional libraries with focused libraries containing a small number of molecules. A previously generative model, CMGNet, was used to generate focused libraries for CReSS. The combined model achieved a Top-10 accuracy of 54.03% when tested on 6,471 13C NMR spectra. In comparison, CReSS with a random reference structure library achieved an accuracy of only 9.17%. Furthermore, to expand the advantages of the focused libraries, we proposed SAmpRNN, which is a recurrent neural network (RNN). With the large focused library amplified by SAmpRNN, the structure-identification accuracy of the model increased in 70.0% of the 30 random example cases. In general, cross-modal retrieval between 13C NMR spectra and structures based on focused libraries (CFLS) achieved high accuracy and provided more accurate candidate structures than traditional libraries for compound identification.

DOTA-based plectin-1 targeted contrast agent enables detection of pancreatic cancer in human tissue

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and lethal malignancy with extremely poor patient survival rates. A key reason for the poor prognosis is the lack of effective diagnostic tools to detect the disease at curable, premetastatic stages. Tumor surgical resection is PDAC first-line treatment, however distinguishing between cancerous and healthy tissue with current imaging tools remains a challenge. In this work, we report a DOTA-based fluorescent probe targeting plectin-1 for imaging PDAC with high specificity. To enable heterogeneous functionalization of the DOTA-core with multiple targeting peptide units and the fluorophore, a novel, fully clickable synthetic route that proceeds in one-pot was developed. Extensive validation of the probe set the stage for PDAC detection in mice and human tissue. Altogether, these findings may pave the way for improved clinical understanding and early detection of PDAC progression as well as more accurate resection criteria.

Unravelling Immune-Inflammatory Responses and Lysosomal Adaptation: Insights from Two-Photon Excited Delayed Fluorescence Imaging

Two-photon excitation (TPE) microscopy with near-infrared (NIR) emission has emerged as a promising technique for deep-tissue optical imaging. Recent developments in fluorescence lifetime imaging with long-lived emission probes have further enhanced the spatial resolution and precision of fluorescence imaging, especially in complex systems with short-lived background signals. In this study, two innovative lysosome-targeting probes, Cz-NA and tCz-NA, are introduced. These probes offer a combination of advantages, including TPE (λex = 880 nm), NIR emission (λem = 650 nm), and thermally activated delayed fluorescence (TADF) with long-lived lifetimes (1.05 and 1.71 µs, respectively). These characteristics significantly improve the resolution and signal-to-noise ratio in deep-tissue imaging. By integrating an acousto-optic modulator (AOM) device with TPE microscopy, the authors successfully applied Cz-NA in two-photon excited delayed fluorescence (TPEDF) imaging to track lysosomal adaptation and immune responses to inflammation in mice. This study sheds light on the relationship between lysosome tubulation, innate immune responses, and inflammation in vivo, providing valuable insights for the development of autofluorescence-free molecular probes in the future.

[Research advances on application of sub-epidermal moisture scanner in monitoring tissue viability of early pressure injuries]

Pressure injury (PI) not only reduces the quality of life of patients but also is expensive to manage, placing a heavy financial burden on patients and their families, and society. Despite the increasing diversity of methods used to identify early PI, there are still few methods that can truly and accurately predict early PI. The sub-epidermal moisture scanner is the first U.S. Food and Drug Administration-authorized PI management device that can predict the occurrence and development of PI by measuring the level of local tissue bio-capacitance and monitoring the tissue viability. As an emerging diagnostic instrument, the sub-epidermal moisture scanner has already shown great advantages in clinical practice, which can promote the informatization, digitization, and intelligent prevention and management of PI. This paper introduces the pathophysiological mechanism of PI, elucidates the working principle and parameter settings of the sub-epidermal moisture scanner, its clinical application in monitoring tissue viability in early PI, and its limitation, and looks forward to its future development.

In Situ Photoacoustic Visualization of Pneumonia Induced by MRSA and Specific Identifying Tumor-Homing Bacteria

Optical imaging holds great promise for monitoring bacterial infectious processes and drug resistance with high temporal-spatial resolution. Currently, the diagnosis of deep-seated bacterial infections in vivo with fluorescence imaging, including near-infrared (NIR) fluorescence imaging technology, remains a significant challenge due to its limited tissue penetration depth. In this study, we developed a highly specific targeting probe, Cy7-Neo-NO2, by conjugating a bacterial 16S rRNA-targeted moiety, neomycin, with a bacterial nitroreductase (NTR)-activated NIR photoacoustic (PA) scaffold using our previously developed caged photoinduced electron transfer (a-PeT) approach. This conjugation effectively resolved probe aggregation issues in physiological conditions and substantially enhanced its reactivity toward bacterial NTR. Notably, Cy7-Neo-NO2 enabled the first in situ photoacoustic imaging of pneumonia induced by methicillin-resistant Staphylococcus aureus (MRSA), as well as the detection of bacteria within tumors. Furthermore, upon NIR irradiation, Cy7-Neo-NO2 successfully inhibited MRSA growth through a synergistic effect combining photothermal therapy and photodynamic therapy. Our results provided an effective tool for obtaining exceptional PA agents for accurate diagnosis, therapeutic evaluation of deep-seated bacterial infections in vivo, and intratumoral bacteria-specific recognition.

Advances in the Application of Artificial Intelligence-Based Spectral Data Interpretation: A Perspective

The interpretation of spectral data, including mass, nuclear magnetic resonance, infrared, and ultraviolet-visible spectra, is critical for obtaining molecular structural information. The development of advanced sensing technology has multiplied the amount of available spectral data. Chemical experts must use basic principles corresponding to the spectral information generated by molecular fragments and functional groups. This is a time-consuming process that requires a solid professional knowledge base. In recent years, the rapid development of computer science and its applications in cheminformatics and the emergence of computer-aided expert systems have greatly reduced the difficulty in analyzing large quantities of data. For expert systems, however, the problem-solving strategy must be known in advance or extracted by human experts and translated into algorithms. Gratifyingly, the development of artificial intelligence (AI) methods has shown great promise for solving such problems. Traditional algorithms, including the latest neural network algorithms, have shown great potential for both extracting useful information and processing massive quantities of data. This Perspective highlights recent innovations covering all of the emerging AI-based spectral interpretation techniques. In addition, the main limitations and current obstacles are presented, and the corresponding directions for further research are proposed. Moreover, this Perspective gives the authors' personal outlook on the development and future applications of spectral interpretation.

[Comparison of the efficacy of thulium fiber laser and holmium laser lithotripsy in the treatment of upper urinary tract stones]

Objective: To compare the efficacy of thulium fiber laser (TFL) and holmium laser (HL) in the treatment of upper urinary tract stones. Methods: A total of 76 patients diagnosed with upper urinary tract stones by radiographic examination and who required ureteroscopy lithotripsy or retrograde intrarenal stone surgery were prospectively enrolled from the Department of Urology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine between January 2022 and June 2022. Patients were divided into TFL group (n=38) and HL group (n=38) in a 1∶1 ratio according to the randomization schedule. The perioperative outcomes and stone-free rate of two groups were recorded and compared. Results: Finally, the clinical data of 71 patients were completely collected, including 55 males and 16 females, with a mean age of (45.7±14.1) years old. There were 36 patients in TFL group and 35 patients in HL group, and there was no significant difference in age, body mass index, gender, Charlson comorbidity index, stone site, stone location, stone size and stone density between two groups (all P>0.05). All the surgeries were successfully performed with no intraoperative complications. There were no significant differences between the two groups in terms of operation time, stone displacement during lithotripsy, visual field clarity, changes in hemoglobin, leukocyte, and C-reactive protein, and length of postoperative hospital stay (all P>0.05), but the laser action time[M (Q1,Q3)] in the TFL group was 30.0 (20.0, 48.8)s, which was significantly shorter than that in the HL group [90.0 (50.0, 120.0)s, P<0.001]. The stone-free rates of TFL group and HL group were 97.2% (35/36) and 88.6% (31/35), and there was no significant difference (P=0.337). The postoperative complication incidences of TFL group and HL group were 36.1% (13/36)and 22.9% (8/35), respectively, and the difference was not significant either (P=0.221). For ureter stones, the laser action time in TFL group was 22.5 (20.0, 43.8)s, which was significantly shorter than that in HL group [80.0 (50.0, 120.0)s, P<0.001]. For stones with maximum diameter≤10 mm, the laser action time in TFL group was 20.0 (10.0, 25.0)s, which was significantly shorter than that in HL group [50.0 (40.0, 80.0)s, P<0.001]. For stones with maximum diameter>10 mm, the laser action time in TFL group was 60.0(42.5, 180.0)s, which was significantly shorter than that in HL group [180.0(120.0, 210.0)s, P=0.035]. For stones with density≤1 000 CT, the laser action time in TFL group was 30.0 (20.0, 45.0)s, which was significantly shorter than that in HL group [95.0 (47.5, 120.0), P=0.001]. For stones with density>1 000 CT, the laser action time in TFL group was 30.0 (20.0, 90.0)s, which was significantly shorter than that in HL group [80.0 (55.0, 180.0)s, P=0.033]. Conclusion: TFL lithotripsy is an effective and safe surgical procedure for the treatment of upper urinary tract stones, with similar clinical efficacy but shorter laser action time compared to HL lithotripsy.

Analyte-Triggered Excited-State Intramolecular Proton Transfer- Delayed Fluorescence: A General Approach for Time-Resolved Turn-On Fluorescence Imaging

The research of delayed fluorescence (DF) has been a hot topic in biological imaging. However, the development of analyte-triggered small molecule DF probes remains a considerable challenge. Herein a novel excited-state intramolecular proton transfer-delayed fluorescence (ESIPT-DF) approach to construct analyte-stimulated DF probes was reported. These new classes of ESIPT-DF luminophores were strategically designed and synthesized by incorporating 2-(2'-hydroxyphenyl)benzothiazole (HBT), a known ESIPT-based fluorophore, as acceptor with a series of classic donor moieties, which formed a correspondingly twisted donor-acceptor pair within each molecule. Thereinto, HBT-PXZ and HBT-PTZ exhibited significant ESIPT and DF characters with lifetimes of 5.37 and 3.65 μs in the solid state, respectively. Furthermore, a caged probe HBT-PXZ-Ga was developed by introducing a hydrophilic d-galactose group as the recognition unit specific for β-galactosidase (β-gal) and ESIPT-DF blocking agent and applied to investigate the influence of metal ions on β-gal activity on the surface of Streptococcus pneumoniae as a convenient tool. This ESIPT-DF "turn-on" approach is easily adaptable for the measurement of many different analytes using only a predictable modification on the caged group without modification of the core structure.

Polymyxin-based fluorescent probes to combat Gram-negative antimicrobial resistance

Reliable diagnostic approaches especially those targeting critical Gram-negative bacteria are urgently needed for the prevention of antimicrobial resistance. Polymyxin B (PMB) which specifically targets the outer membrane of Gram-negative bacteria is the last-line antibiotic against life-threatening multidrug-resistant Gram-negative bacteria. However, increasing number of studies have reported the spread of PMB-resistant strains. With the aim to specifically detect Gram-negative bacteria and potentially reduce the irrational use of antibiotics, we herein rationally designed two Gram-negative bacteria specific fluorescent probes based on our previous activity-toxicity optimization of PMB. The in vitro probe PMS-Dns showed fast and selective labeling of Gram-negative pathogens in complex biological cultures. Subsequently, we constructed the caged in vivo fluorescent probe PMS-Cy-NO₂ by conjugating bacterial nitroreductase (NTR)-activatable positive charged hydrophobic near-infrared (NIR) fluorophore with polymyxin scaffold. Significantly, PMS-Cy-NO₂ exhibited excellent Gram-negative bacterial detection capability with the differentiation between Gram-positive and Gram-negative in a mouse skin infection model.

Characterization of Chlorogenic Acid as a Two-Photon Fluorogenic Probe that Regulates Glycolysis in Tumor Cells under Hypoxia

High levels of steady-state mitochondrial reactive oxygen species (ROS) and glycolysis are hallmarks of cancer. An improved understanding of interactions between tumor energetics and mitochondrial ROS modulation is useful for the development of new anticancer strategies. Here, we show that the natural product chlorogenic acid (CGA) specifically scavenged abnormally elevated mitochondrial O₂^•- and exhibited a two-photon fluorescence turn-on response to tumor cells under hypoxia and tumor tissues in vivo. Furthermore, we illustrated that CGA treatment reduced O₂^•- levels in cells, hampered activation of AMP-activated protein kinase (AMPK), and shifted metabolism from glycolysis to oxidative phosphorylation (OXPHOS), resulting in inhibition of tumor growth under hypoxia. This study demonstrates an efficient two-photon fluorescent tool for real-time assessment of mitochondrial O₂^•- and a clear link between reducing intracellular ROS levels by CGA treatments and regulating metabolism, as well as undeniably helpful insights for the development of new anticancer strategies.

Thermally activated delayed fluorescence emitters: a thionation approach toward next-generation photosensitizers

Achieving highly efficient intersystem crossing (ISC) remains a key focus in the design of heavy atom-free photosensitizers (PSs) for various photophysical and photochemical applications. Herein, we report a general and robust molecular design strategy for obtaining photoactivatable heavy atom-free PSs by performing a simple sulfur substitution of carbonyl oxygen atoms of a thermally activated delayed fluorescence (TADF) emitter. This thionation led to a significant fluorescence loss, resulting in an increased ISC transformation. Upon white-light irradiation, the sulfur-substituted TADF compound (S-AIOH-Cz) exhibited a long-lived fluorescence turn-on response, a long-lasting triplet state lifetime and a superior reactive oxygen species (ROS) generation ability, which is desirable for time-resolved fluorescence imaging and photodynamic disinfection against antimicrobial resistance.

Hyperglycemia in Diabetic Skin Infections Promotes Staphylococcus aureus Virulence Factor Aureolysin: Visualization by Molecular Imaging

Bacterial skin infections are common in diabetic patients, with Staphylococcus aureus (S. aureus) being the most commonly isolated, causing comorbidities such as increased mortality and long-term hospitalization. While precise mechanisms remain to be determined, hyperglycemia represents an important pathogenetic factor responsible for the increased risk of S. aureus infection. Herein, we constructed a series of ratiometric fluorescent molecular probes for aureolysin (Aur), a major virulence factor in S. aureus. Using probe 1, we were able to determine specific Aur activity in both cells and tissues. We also observed that elevated glucose levels led to 2-fold higher Aur expression in S. aureus cultures. In a diabetic mouse model, we used molecular imaging to demonstrate that hyperglycemia tripled S. aureus Aur virulence compared to nondiabetic mice, resulting in more severe infections.

[PAHs exposure and its association with oxidative stress and neurotransmitter levels in coal miners]

Objective: To learn the investigate of polycyclic aromatic hydrocarbons (PAHs) and to explore the association between PAHs exposure and oxidative stress' neurotransmitter levels in coal miners. Methods: A cross-sectional survey was conducted in 652 coal miners (239 in the underground first line group, 280 in the underground auxiliary group and 133 in the surface group) from April to June 2017. The levels of urinary monohydroxy PAHs metabolites (OH-PAHs) , oxidative stress and neurotransmitters in blood were determined. A linear regression model was used to evaluate the correlation between OH-PAHs and oxidative stress' neurotransmitter levels. The mediating role of oxidative stress between urinary OH-PAHs and neurotransmitters change was assessed by mediation analysis. Results: The levels of 2-hydroxynaphthalene (2-NAP) 、2-hydroxy uorene (2-FLU) 、1-hydroxypyrene (1-OHP) in urine OH-PAHs of coal miners in different workplaces were significantly different (H=33.64, 9.63, 26.82, P<0.01, =0.008, <0.01) . The levels of neurotransmitters [5-hydroxytryptamine (5-HT) , norepinephrine (NE) , epinephrine (E) , dopamine (DA) , acetylcholine (Ach) , acetylcholinesterase (AChE) ] and oxidative stress [malondialdehyde (MDA) (F=36.81, 15.58, 79.16, 179.58, 33.48, 67.63, 4.96, P<0.01) ] in the blood of three groups of coal miners were significantly different. After controlling the potential confounding factors, NE content was negatively correlated with 2-FLU level, and AChE activity was also negatively correlated with 1-OHP level (β=-134.99, 95% CI: -250.74~-19.23, P=0.02; β=-0.80, 95%CI: -1.54~-0.05, P=0.036) . Positive correlation was found between Ach content and 9-hydroxyphenanthrene (9-PHE) level, AChE activity was also positively correlated with 2-NAP level and 9-PHE level (β=0.96, 95%CI: 0.26~1.64, P=0.007; β=1.78, 95%CI: 0.75~2.82, P=0.001; β=0.77, 95%CI: 0.07~1.47, P=0.031) . In addition, superoxide dismutase activity was correlated with 1-OHP level and AChE activity (β=0.32, 95%CI: 0.02~0.62, P=0.034; β=-0.23, 95%CI: -0.43~-0.02, P=0.032) . Mediation analysis indicated that 1-OHP level may directly affect AChE activity (P<0.05) . Conclusion: The level of PAHs in underground coal miners is relatively higher, and may lead to changes of neurotransmitter levels. The mediating effect of oxidative stress has not been observed.

[Clinical report of hoding cricoarytenoid joint reduction with visual laryngoscope under intravenous anesthesia]

Objective: To investigate the reduction effect of hoding cricoarytenoid joint reduction with visual laryngoscope under intravenous anesthesia. Methods: The therapeutic effects of 40 patients with arytenoid dislocation(AD)treated by closed reduction in the single center from January 2020 to September 2021 were retrospectively analyzed, including 21 males and 19 females, median age 48 years. The etiology, symptoms, preoperative evaluation methods, reduction mode, reduction times, and the recovery of arytenoid cartilage movement and sound after reduction were evaluated and analyzed. Results: All patients had obvious hoarseness and breath sound before treatment. Under stroboscopic laryngoscope or electronic nasopharyngoscope, different degrees of vocal cord movement disorder and poor glottic closure can be seen. There were 28 cases of left dislocation, 9 cases of right dislocation and 3 cases of bilateral dislocation. The etiology of dislocation of cricoarytenoid joint: 25 cases (62.5%) of tracheal intubation under general anesthesia were the most common causes, was as follows by laryngeal trauma, gastroscopy, cough, vomiting and so on. Among them, 28 cases of reduction were initially diagnosed in our department, and 12 cases were diagnosed later after failure of reduction treatment. Of the 40 patients, 6 underwent reduction 24 hours after dislocation; 18 cases from 3 days to 1 month; 7 cases from 1 to 3 months; 6 cases were reset in 3~6 months; Over 6 months in 3 cases. After one reduction, 10 cases (10/40, 25%) recovered normal pronunciation, 14 cases (14/40, 35%) recovered normal pronunciation after two reduction, 10 cases (10/40, 25%) recovered normal pronunciation after three times, 2 cases (2/40, 5%) recovered normal pronunciation after four times, and 1 case (2.5%) recovered normal pronunciation after five times. Thin slice CT scan of larynx and cricoarytenoid joint reconstruction showed the types of AD: subluxation in 37 cases (92.5%) and total dislocation in 3 cases; 28 cases of left dislocation, 9 cases of right dislocation and 3 cases of bilateral dislocation; 29 cases (72.5%) had posterior dislocation and 11 cases (27.5%) had anterior dislocation. All patients were treated by intravenous anesthesia with arytenoid cartilage clamped by cricoarytenoid joint reduction forceps under visual laryngoscope. The curative effect was evaluated by stroboscopic laryngoscope and/or voice analysis at 1-2 weeks after operation. The vocal cord movement returned to normal and the pronunciation was good in 37 cases (92.5%). Conclusions: Hoding cricoarytenoid joint reduction with the vision laryngoscope under intravenous anesthesia is easy to operate and the reduction effect is more stable. It is a effective method for AD.

Membrane dual-targeting probes: A promising strategy for fluorescence-guided prostate cancer surgery and lymph node metastases detection

Fluorescence-guided surgery (FGS) with tumor-targeted imaging agents, particularly those using the near-infrared wavelength, has emerged as a real-time technique to highlight the tumor location and margins during a surgical procedure. For accurate visualization of prostate cancer (PCa) boundary and lymphatic metastasis, we developed a new approach involving an efficient self-quenched near-infrared fluorescence probe, Cy-KUE-OA, with dual PCa-membrane affinity. Cy-KUE-OA specifically targeted the prostate-specific membrane antigen (PSMA), anchored into the phospholipids of the cell membrane of PCa cells and consequently showed a strong Cy7-de-quenching effect. This dual-membrane-targeting probe allowed us to detect PSMA-expressing PCa cells both in vitro and in vivo and enabled clear visualization of the tumor boundary during fluorescence-guided laparoscopic surgery in PCa mouse models. Furthermore, the high PCa preference of Cy-KUE-OA was confirmed on surgically resected patient specimens of healthy tissues, PCa, and lymph node metastases. Taken together, our results serve as a bridge between preclinical and clinical research in FGS of PCa and lay a solid foundation for further clinical research.

Donor manipulation for constructing a pH sensing thermally activated delayed fluorescent probe to detect alkaliphiles

pH homeostasis is essential for alkaliphiles, given their widespread use in biotechnological applications. However, quantitative monitoring of alkaline pH in alkaliphiles remains challenging. Here, we synthesized for the first time, a thermally activated delayed fluorescent (TADF) pH probe: NI-D-OH. Our probe exhibits a good linear relationship between fluorescence intensity and pH in the neutral to alkaline range (pH 7.0-8.6), as well as long-lived TADF emission. We further show that NI-D-OH can be used to monitor intracellular pH in living organisms, and evaluate the effect of Na⁺ on the pH homeostasis, demonstrating the potential for alkaline pH monitoring and time-resolved fluorescence imaging.

[Application of serum markers in medullary thyroid carcinoma]

Objective: To discuss the diagnostic value of calcitonin(CT), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), pro-gastrin releasing peptide (Pro-GRP) and chromogranin A (CgA) in the identification of medullary thyroid carcinoma (MTC). Methods: The CT levels in 105 cases of MTC, 50 cases of papillary thyroid carcinoma, 10 cases of thyroid follicular carcinoma, 5 cases of undifferentiated thyroid carcinoma, 50 cases of benign thyroid diseases, 30 cases of non-thyroid malignant tumors and 50 cases of healthy controls were measured from February 2017 to August 2019 at the Department of Clinical Laboratory, Cancer Hospital affliated to Fudan University. Additionally, 79 cases of MTC, 30 cases of non-MTC thyroid malignant tumors and 30 healthy controls were selected for the measurement of CEA, NSE, Pro-GRP and CgA levels. The receiver operating curve was utilized to clarify the area under the curve (AUC), sensitivity, and specificity of each indicator to distinguish between different groups. Results: The medians of CT concentrations in the group of MTC patients was 607.2 (152.5,2 777.5)pg/ml, which was statistically significantly higher than that of the subjects in the group of papillary thyroid carcinoma 1.48 (0.5,2.91)pg/ml, follicular thyroid carcinoma 1.90 (0.82,2.99)pg/ml, undifferentiated thyroid carcinoma 0.50 (0.50,4.93)pg/ml, benign thyroid disease 1.30 (0.50,2.79)pg/ml, non-thyroid malignancies 1.36 (0.50,2.89)pg/ml and healthy controls 2.05 (0.89,3.18)pg/ml. The sensitivity, specificity and AUC of CT to distinguish MTC vs. non-MTC patients was 96.2%, 99.3% and 0.99, respectively. The maximum diameter (>1 cm, P=0.001, OR=15.74) and number (>1, P=0.04, OR=3.4) of nodules were two independent risk factors for elevated CT. CEA (AUC=0.94), NSE (AUC=0.65), Pro-GRP (AUC=0.94) and CgA (AUC=0.83) could all distinguish MTC vs. non-MTC thyroid malignancies. The AUC, sensitivity and specificity by combining CT, CEA, NSE, Pro-GRP and CgA to differentiate MTC vs. non-MTC thyroid malignancies was 1, 100% and 100%, respectively. Conclusions: CT, CEA, NSE, Pro-GRP and CgA may be helpful for the auxiliary diagnosis of MTC. The combination of these indicators in the diagnosis of MTC has high sensitivity and specificity.

[Recent HIV infection and associated factors among men who have sex with men in Jiangsu province]

Objective: To understand the incidence of HIV infections and associated factors among men who have sex with men (MSM) in Jiangsu province. Methods: Based on national AIDS sentinel surveillance in 2019, MSM from 13 cities in Jiangsu were recruited for questionnaire interview and laboratory testing during April to July, 2019. Seropositive samples were tested with Limiting-antigen avidity enzyme immunoassay to detect recent HIV infections. The incidence of HIV infection in MSM were calculated according to the formula and parameters from China CDC. Multivariable logistic regression analysis was used to identify factors associated with recent infection of HIV. Results: A total of 4 469 MSM were subjects and the incidence of HIV infection were 4.5% (95%CI: 3.4%-5.5%).Multivariate logistic regression analysis results showed that compared with these aged ≥40 years, recruitment ways from MSM venues, awareness of AIDS knowledge, non-unprotected anal sex in the past 6 months and non-syphilis infection, those who aged 18-24 years (aOR=2.083,95%CI:1.087-3.990), recruitment ways from VCT clinics (aOR=2.125,95%CI:1.175-3.843), unawareness of AIDS knowledge (aOR=2.456,95%CI:1.109-5.437), unprotected anal sex in the past 6 months (aOR=3.553,95%CI:2.143-5.889) and syphilis infection (aOR=2.414,95%CI:1.033-5.462) were higher risk of HIV infection. Conclusion: The new infection rates of HIV were high in MSM in Jiangsu province. Health education, condom use and HIV/syphilis screening promotions should therefore be top priority in the prevention and control of HIV infection in MSM.

Investigating the Potential Mechanism of Pydiflumetofen Resistance in Sclerotinia sclerotiorum

The necrotrophic pathogen Sclerotinia sclerotiorum is one of the most damaging and economically important plant pathogens. Pydiflumetofen, which was developed by Syngenta Crop Protection, has already been registered in China for the management of Sclerotinia stem rot, which was caused by S. sclerotiorum in oilseed rape. In an attempt to preempt and forestall the development of resistance to this useful fungicide, the current study was initiated to investigate the potential mechanism of resistance in laboratory mutants. Five pydiflumetofen-resistant S. sclerotiorum mutants were successfully generated by repeated exposure to the fungicide under laboratory conditions. Although the mutants had greatly reduced sensitivity to pydiflumetofen, they were also found to have significantly (P < 0.05) reduced fitness, exhibiting reduced mycelial growth and sclerotia formation on potato dextrose agar medium. However, three of the four mutants had significantly (P < 0.05) increased pathogenicity on detached soybean leaves compared with their respective parental isolates, indicating a moderate to high level of fungicide resistance risk according to the criteria of the Fungicide Resistance Action Committee. Sequence analysis of four succinate dehydrogenase (Sdh) target genes identified several nucleotide changes in the sequences of the pydiflumetofen-resistant mutants, most of which were synonymous and caused no changes to the predicted amino acid sequences. However, all of the pydiflumetofen-resistant mutants had two amino acid point mutations (A11V and V162A) in their predicted SsSdhB sequence. No similar changes were found in the SsSdhA, SsSdhC, and SsSdhD genes of any of the mutants tested. In addition, there was a positive cross-resistance between pydiflumetofen and boscalid, and no cross-resistance between pydiflumetofen and other commonly used fungicides, including tebuconazole, fludioxonil, cyprodinil, dimethachlone, prochloraz, pyraclostrobin, fluazinam, procymidone, and carbendazim. These results indicate that pydiflumetofen has great potential as an alternative fungicide for the control of S. sclerotiorum, especially where resistance to other fungicides has already emerged. Mixing or alternate application with fludioxonil, prochloraz, and fluazinam could be used to limit the risk of resistance to pydiflumetofen.

Impact of the COVID-19 pandemic on emergency healthcare utilization: a cohort study

Background

Emergency department (ED) crowding is a burden on public health, so understanding the characteristics of frequent ED users is a key concern of the healthcare system and policy makers. This study aims to examine the characteristics and healthcare-seeking behaviors in frequent ED users before and during the COVID-19 pandemic.

Methods

A retrospective observational study was conducted on ED users aged 18 years and over admitted to Taipei City Hospital in February 2019-January2020 (before pandemic) and February 2020-January2021 (during pandemic) (N = 120,011). Frequent and ED users were defined as patients with four or more ED visits in a year. Multivariate logistic regression was used to identify the predictors of frequent ED use before and during the COVID-19 pandemic.

Results

Monthly emergency department visits were significantly lower during the pandemic (by 10.1-26.8%). Frequent ED patients had shorter lengths of stay in the ED during the pandemic (212.5 vs.233.9 minutes; P &lt; 0.0001). The proportion of ED patients receiving chest CT examination during the pandemic has increased by 0.5-0.6%. After adjusting for sociodemographic factors, triage status, mode of arrival, and copayment exemption, patients with a triage status of level 4-5 (AOR=1.60, 95% CI: 1.13-2.28), diagnosis of pneumonia (AOR=1.85, 95% CI: 1.07-3.17), giddiness (AOR=2.85, 95% CI: 1.82-4.45), dyspnea (AOR=1.85, 95% CI: 1.00-3.39), or chronic kidney disease (AOR=5.05, 95% CI: 2.66-9.59) were more likely to be frequent ED visitors during the pandemic.

Conclusions

Since SAR-CoV-2 is highly contagious, it is imperative to educate non-emergent patients to utilize outpatient medical services rather than emergency medical services to reduce the risk of COVID-19 outbreaks at the ED.

Key messages

This study found that the utilization of emergent medical services during the COVID-19 pandemic significantly decreased by 10.1%–26.8% compared to before the COVID-19 pandemic. The lengths of stay in frequent ED users during the COVID-19 pandemic were significantly shorter than that in frequent ED users before the COVID-19 pandemic.

Mask reuse during the COVID-19 pandemic: a national survey in Taiwan

Background

The use of masks is an effective measure to prevent severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection; however, mask reuse is not recommended. Studies examining the factors associated with mask reuse during the coronavirus disease (COVID-19) pandemic are limited. This nationwide survey aimed to determine the prevalence and factors associated with mask reuse among Taiwanese citizens during the pandemic.

Methods

From May 18 through May 31, 2020, a computer-assisted telephone interview system was used to randomly select Taiwanese citizens who were interviewed for COVID-19 preventive behaviors and knowledge on the usage of masks. Multivariate logistic regression was used to identify factors associated with mask reuse during the COVID-19 pandemic. Moreover, generalized estimating equations (GEE) were used to analyze the rate of mask reuse among participants before and during the pandemic.

Results

For a total of 1,075 participants, the overall mean age was 57.4 years, and 82.2% of participants reported mask reuse during the COVID-19 pandemic. After controlling for other covariates, participants who had a greater knowledge on mask usage or had a high supply of masks were less likely to reuse masks during the pandemic. GEE analysis showed that compared with the participants' mask wearing behaviors before the COVID-19 pandemic, they were more likely to reuse masks during the pandemic.

Conclusions

The rate of mask reuse among the general population during the pandemic was significantly higher than that before the pandemic. Individuals were less likely to reuse masks if they had adequate knowledge on mask usage or had a high supply of masks. Since mask reuse is associated with a higher risk of COVID-19 due to the possibility of wearing SAS-CoV-2-contaminated masks, it is imperative to educate people on the correct usage of masks. Further, the government should provide sufficient masks to the general population to decrease the reuse of masks.

Key messages

Mask reuse increased during the COVID-19 pandemic due to the shortage in supply. It is imperative to educate people about the correct usage of masks.

Exploring the Biological and Molecular Characteristics of Resistance to Fludioxonil in Sclerotinia sclerotiorum From Soybean in China

Sclerotinia sclerotiorum is one of the most damaging and economically important necrotrophic plant pathogens, infecting more than 400 plant species globally. Although the phenylpyrrole fungicide fludioxonil has high activity against S. sclerotiorum, reports indicate that there is also substantial potential for the development of fungicide resistance. However, the current study investigating five fludioxonil-resistant laboratory mutants found a significant fitness cost associated with fludioxonil resistance resulting in significantly (P < 0.05) reduced mycelial growth and sclerotia formation on potato dextrose agar as well as significantly (P < 0.05) lower pathogenicity on detached tomato leaves, with one mutant, LK-1R, completely losing the capacity to cause infection. In addition, all of the fludioxonil-resistant mutants had significantly (P < 0.05) increased sensitivity to osmotic stress (0.5 M of potassium chloride and 1.0 M of glucose), which is consistent with the proposed fludioxonil target sites within the high osmolarity glycerol stress response mitogen-activated protein kinase (HOG1-MAPK) signaling transduction pathway. Sequence analysis of six genes from this two-component pathway, including SsHk, SsYpd, SsSk1, SsSk2, SsPbs, and SsHog, revealed several mutations that may be associated with fludioxonil resistance. For example, six separate point mutations were found in SsHk that led to changes in the predicted amino acid sequence, including A136G, F249V, G353A, E560K, M610K, and K727R. Similarly, SsPbs had three mutations (D34G, S46L, and L337E), SsSk1 and SsYpd had two (S53G and A795V for SsSk1, and E67G and Y141H for SsYpd), and SsHog and SsSk2 had one each (V220A and S763P, respectively). To our knowledge, these constitute the first reports of amino acid changes in proteins of the HOG1-MAPK pathway being associated with fludioxonil resistance in S. sclerotiorum. This study also showed a positive cross-resistance between fludioxonil and dimethachlone and procymidone, but none with tebuconazole or carbendazim, indicating that the inclusion of tebuconazole within an integrated pest management program could reduce the risk of fludioxonil resistance developing in field populations of S. sclerotiorum and ensure the sustainable production of soybeans in China into the future.

Developing fluoromodule-based probes for in vivo monitoring the bacterial infections and antibiotic responses

Recently, antibiotic resistant has become a serious public health concern, which warrants new generations of antibiotics to be developed. Pharmacodynamic evaluation is crucial in drug discovery processes. Despite numerous advanced imaging systems are available nowadays, technologies for the sensitive in vivo diagnosis of bacterial infections and direct visualization of drug efficacy are yet to be developed. In this study, we have developed novel near-infrared (NIR) fluorogenic probes. These probes are dark in solution but highly fluorescent when bound to the cognate reporter, fluorogen-activating protein (FAP). We established the in vivo bacterial infection model using FAP_dH6.2 recombinantly expressed E. coli and applied this NIR fluoromodule-based system for diagnosing bacterial infections and monitoring disease progressions and its responses to a type of antibiotics through classic mechanism of membrane lysis. This NIR fluoromodule-based system will discover new information on bacterial infections and identify newer antibacterial entities.

[Robot-assisted nephroureterectomy requiring no robot redocking or patient repositioning: experience from a single center with 62 cases]

Objective: To examine a new technique of robot-assisted nephroureterectomy without robot reldocking or patient repositioning. Methods: Patients diagnosed as upper tract urothelial carcinoma treated with this modality between November 2015 and January 2019 at Department of Urology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine were included in this analysis. Data collection including patient demographics, operative procedure and postoperative morbidities were conducted by retrospective charts review, after receiving the institutional review board's approval. There were 35 males and 27 females with a median age of 70 years (range: 30 to 91 years) underwent single docking robot-assisted nephroureterectomy without repositioning. Among the 62 cases, 37 patients had pelvic carcinoma while 25 patients had ureteral carcinoma (with proximal portion 12 cases, middle portion 5 cases and distal portion 8 cases). The patient was placed in a 60 to 80-degree, modified flank position with a 15-degree Trendelenburg tilt. The contralateral arm was positioned perpendicular to the torso on an arm board while the ipsilateral arm was taped to the patient's side with ample padding. The robot cart was then docked at a 90-degree angle, perpendicular to the patient. A "W"-shape, three robotic-arm configurations was used for port placement. Results: The surgical procedures were performed successfully in all the 62 patients. The operation time was (171.6±54.7) minutes (range: 60 to 370 minutes). The estimated blood loss during the operation was 50(50) ml (range: 20 to 400 ml) with 4 patients had transfusion. No perioperative death was encountered. Eleven patients had post-operative complications (Clavien-Dindo grade 2) including 3 cases of hemorrhage and 8 cases of chylous leakage. All cases were regularly followed up with a median time of 37 months (range: 17 to 55 months). There were 8, 30, 19, 4 and 1 case followed up for 48, 36, 24, 18 and less than 18 months, respectively. Three patients had reginal recurrences and 11 cases of distant metastasis occurred, with 5 patients died for cancer. The survival rate within 24 months was estimated as 75.4%(43/57). Conclusion: Robot-assisted nephroureterectomy without robot redocking or patient repositioning could be safely reproduced, with surgical outcomes comparable to other established techniques.

DOTAM-Based, Targeted, Activatable Fluorescent Probes for the Highly Sensitive and Selective Detection of Cancer Cells

The utilization of an activatable, substrate-based probe design in combination with a cellular targeting approach has been rarely explored for cancer imaging on a small-molecule basis, although such probes could benefit from advantages of both concepts. Cysteine proteases like cathepsin S are known to be involved in fundamental processes associated with tumor development and progression and thus are valuable cancer markers. We report the development of a combined dual functional DOTAM-based, RGD-targeted internally quenched fluorescent probe that is activated by cathepsin S. The probe exhibits excellent in vitro activation kinetics which can be fully translated to human cancer cell lines. We demonstrate that the targeted, activatable probe is superior to its nontargeted analog, exhibiting improved uptake into α_νβ₃-integrin expressing human sarcoma cells (HT1080) and significantly higher resultant fluorescence staining. However, profound activation was also found in cancer cells with a lower integrin expression level, whereas in healthy cells almost no probe activation could be observed, highlighting the high selectivity of our probe toward cancer cells. These auspicious results show the outstanding potential of the dual functionality concept combining a substrate-based probe design with a targeting approach, which could form the basis for highly sensitive and selective in vivo imaging probes.

Biological Characteristics and Molecular Mechanisms of Fludioxonil Resistance in Fusarium graminearum in China

Fusarium graminearum is the primary causal agent of Fusarium head blight (FHB) of wheat. The phenylpyrrole fungicide fludioxonil is not currently registered for the management of FHB in China. The current study assessed the fludioxonil sensitivity of a total of 53 F. graminearum isolates collected from the six most important wheat-growing provinces of China during 2018 and 2019. The baseline fludioxonil sensitivity distribution indicated that all of the isolates were sensitive, exhibiting a unimodal cure with a mean effective concentration for 50% inhibition value of 0.13 ± 0.12 μg/ml (standard deviation). Five fludioxonil-resistant mutants were subsequently induced by exposure to fludioxonil under laboratory conditions. Ten successive rounds of subculture in the absence of the selection pressure indicated that the mutation was stably inherited. However, the fludioxonil-resistant mutants were found to have reduced pathogenicity, higher glycerol accumulation, and higher osmotic sensitivity than the parental wild-type isolates, indicating that there was a fitness cost associated with fludioxonil resistance. In addition, the study also found a positive cross resistance between fludioxonil, procymidone, and iprodione, but not with other fungicides such as boscalid, carbendazim, tebuconazole, and fluazinam. Sequence analysis of four candidate target genes (FgOs1, FgOs2, FgOs4, and FgOs5) revealed that the HBXT2R mutant contained two point mutations that resulted in amino acid changes at K223T and K415R in its FgOs1 protein, and one point mutation at residue 520 of its FgOs5 protein that resulted in a premature stop codon. Similarly, the three other mutants contained point mutations that resulted in changes at the K192R, K293R, and K411R residues of the FgOs5 protein but none in the FgOs2 and FgOs4 genes. However, it is important to point out that the FgOs2 and FgOs4 expression of all the fludioxonil-resistant mutants was significantly (P < 0.05) downregulated compared with the sensitive isolates (except for the SQ1-2 isolate). It was also found that one of the resistant mutants did not have changes in any of the sequenced target genes, indicating that an alternative mechanism could also lead to fludioxonil resistance.

Dual-Mode Detection of Bacterial 16S Ribosomal RNA in Tissues

The specific detection of pathogens has long been recognized as a vital strategy for controlling bacterial infections. Herein, a novel hydrophilic aromatic-imide-based thermally activated delayed fluorescence (TADF) probe, AI-Cz-Neo, is designed and synthesized by the conjugation of a TADF emitter with a bacterial 16S ribosomal RNA-targeted moiety, neomycin. Biological data showed for the first time that AI-Cz-Neo could be successfully applied for the dual-mode detection of bacterial 16S rRNA using confocal fluorescence imaging and time-resolved fluorescence imaging (TRFI) in both cells and tissues. These findings greatly expand the application of TADF fluorophores in time-resolved biological imaging and provide a promising strategy for the precise and reliable diagnosis of bacterial infections based on the dual-mode imaging of bacterial 16S rRNA by fluorescence intensity and fluorescence lifetime.

An Activatable Lanthanide Luminescent Probe for Time-Gated Detection of Nitroreductase in Live Bacteria

Herein we report the development of a turn‐on lanthanide luminescent probe for time‐gated detection of nitroreductases (NTRs) in live bacteria. The probe is activated through NTR‐induced formation of the sensitizing carbostyril antenna and resulting energy transfer to the lanthanide center. This novel NTR‐responsive trigger is virtually non‐fluorescent in its inactivated form and features a large signal increase upon activation. We show that the probe is capable of selectively sensing NTR in lysates as well as in live bacteria of the ESKAPE family which are clinically highly relevant multiresistant pathogens responsible for the majority of hospital infections. The results suggest that our probe could be used to develop diagnostic tools for bacterial infections.

Rapid differentiation between bacterial infections and cancer using a near-infrared fluorogenic probe

The reliable differentiation between bacterial infections and other pathologies is crucial for both diagnostics and therapeutic approaches. To accommodate such needs, we herein report the development of an activatable near-infrared fluorescent probe 1 that could be applied in the ultrafast, ultrasensitive and specific detection of nitroreductase (NTR) activity in bacterial pathogens both in vitro and in vivo. Upon reaction with NTR, the nitro-group of the para-nitro phenyl sulfonic moiety present in probe 1 was reduced to an amino-group, resulting in a near-infrared fluorescence turn-on of the latent cyanine 7 fluorophore. Probe 1 was capable of rapid and real-time quantitative detection of 0–150 ng mL⁻¹ NTR with a limit of detection as low as 0.67 ng mL⁻¹in vitro. In addition, probe 1 exhibited an outstanding performance of ultrafast measurements and suitable selectivity toward NTR to accurately sense intracellular basal NTR in ESKAPE bacterial pathogens. Most remarkably, probe 1 was capable of noninvasively identifying bacterial infection sites without showing any significantly increased signal of tumour sites in the same animal within 30 min.

A new nitroreductase-responsive near-infrared fluorogenic probe can specifically image live bacteria in mouse models and does not accumulate at sites of inflammation or tumor.

[Reconstruction of orbital floor defect with preserved orbital contents after advanced maxillary sinus cancer resection]

Objective: To analyze the method and effect of reconstruction of the orbital floor defect with preserved orbital contents after advanced maxillary sinus cancer resection. Methods: Thirty-three patients of T3/T4 stage maxillary sinus cancer with orbital invasion who were treated in Shandong Provincial Hospital from January 2010 to October 2016 were retrospectively analyzed, including 20 males and 13 females, aged from 12 to 80 years old. Patients were treated with appropriate surgical methods according to their clinical manifestation, imaging finding, invasion range, preoperative and intraoperative pathology. Surgical approaches such as maxillectomy, expanded maxillectomy and superstructure maxillectomy were used for patients with Medpor orbit floor repairment. Patients were followed up regularly after surgery, and the surgical efficacy was discussed by descriptive statistical method. Results: Of those 33 cases, 19 were squamous cell carcinoma, 8 were adenoid cystic carcinoma, 5 were inverted papilloma malignant transformation, and 1 was myoepithelial carcinoma in our study. After tumor resection and orbital floor repair, the orbital contents and eyeball function of all patients remained intact. During follow-up time ranged from 3 to 8 years, a total of 6 patients relapsed at 3 years and died of ineffective treatment. The survival rate was 81.8% (27/33). Conclusion: Tumor resection and Medpor orbital floor repair in maxillary sinus cancer patients with orbital invasion can preserve the function of the eyeball well, greatly improve the quality of patient's life.

Self-assembling morphology-tunable single-component supramolecular antibiotics for enhanced antibacterial manipulation

This single-component supramolecular antibiotic can undergo reversible self-assembling morphology transitions under sequential ultrasonic and redox stimuli. The self-assemblies with different morphologies display effective antibacterial regulation.

A single component self-assembled thermally activated delayed fluorescence nanoprobe

A novel versatile thermally activated delayed fluorescence (TADF) nanoprobe, AI-Cz-NP, was constructed by self-assembly of a single-component amphiphilic monomer for potential applications in confocal imaging and time-resolved fluorescence imaging.

[Application of augmented-reality surgical navigation technology combined with ICG molecular fluorescence imaging in laparoscopic hepatectomy]

Objective: To study the application value of augmented-reality (AR) surgical navigation technology combined with indocyanine green (ICG) molecular fluorescence imaging in three-dimensional (3D) laparoscopic hepatectomy. Methods: The clinical data of forty-eight patients who had undergone 3D laparoscopic hepatectomy for hepatocellular carcinoma at First Department of Hepatobiliary Surgery, Zhujiang Hospital, Southern Medical University from January 2018 to April 2019 were retrospectively analyzed.The patients were divided into two groups: the group of 3D laparoscopic hepatectomy navigated by augment reality technology combined with ICG molecular fluorescence imaging (Group A) , and group of conventional 3D laparoscopic hepatectomy (Group B) . Patients in Group A (n=23) underwent 3D laparoscopic hepatectomy using augmented-reality technology combined with ICG molecular fluorescence imaging. In this group, the self-developed three-dimensional laparoscopic augmented-reality surgical navigation system (No. 2018SR840555) was operated to project the preoperative three-dimensional model to the surgical field, and the use of this system in combination with ICG molecular fluorescence imaging navigated laparoscopic hepatectomy. No surgical navigation technology was applied in Group B (n=25) . All patients signed the informed consent, which were in accordance with the requirements of medical ethics (Ethics No.: 2018-GDYK-003) . The preoperative data, surgical indicators and postoperative complications between the two groups were compared and analyzed. Results: The median amount of intraoperative blood loss of Group A was 250 (200) ml (M (Q(R)) ) , which was significantly lower than that of Group B (300 (150) ml) (Z=-2.307, P=0.021) .The transfusion rate of Group A was 13.0% (3/23) , which was significantly lower than that of Group B (40.0%, 10/25) (χ(2)=4.408, P=0.036) .The median postoperative hospitalization time of Group A was 8 (2) d, which was significantly shorter than that of Group B (11 (6.5) d) (Z=-2.694, P=0.007) . There were no serious complications and perioperative death in both groups.The incidence of postoperative complications in Group A was 17.4% (4/23) , which was not significantly different from that in group B (28%, 7/25) (χ(2)=0.763, P=0.382) . Conclusion: Augmented-reality surgical navigation technology combined with ICG molecular fluorescence imaging has better effect in 3D laparoscopic hepatectomy.

A fluorescent probe based on tetrahydro[5]helicene derivative with large Stokes shift for rapid and highly selective recognition of hydrogen sulfide

In this work, we have designed and synthesized a dinitrobenzene-sulfonate tetrahydro[5]helicene (H-DNP) as an effective fluorescent probe for detection of hydrogen sulfide (H₂S). Upon the addition of H₂S, a significant fluorescence enhancement (75-fold) at 495 nm can be observed with a distinct color change from colorless to yellow. Additionally, H-DNP shows low background spectroscopic signal, large Stokes Shift up to ~140 nm, good sensitivity, rapid response time less than 2 min, low detection limit (48 nM) and high selectivity toward common bio-thiols (Cysteine, Homocysteine and Glutathione). Compared with the previous dinitrophenoxy tetrahydro[5]helicene, this probe has shorter response time and lower detection limit. Most importantly, this probe H-DNP has low toxicity to cells and excellent cell permeability, which can be applied to visualize H₂S in living cells.

Rapid Synthesis of γ-Halide/Pseudohalide-Substituted Cyanine Sensors with Programmed Generation of Singlet Oxygen

A range of γ-halide/pseudohalide-substituted cyanine-based photosensitizers with programmed levels of singlet oxygen generation capability have been developed as theranostic agents for photodynamic therapy of cancer and infectious diseases.

[Application of adaptie statistical iterative reconstruction technology combined with low tube voltage in three phase enhanced low dose liver scanning]

Objective: To explore the application value of adaptive statistical iterative reconstruction (ASIR) combined with low tube voltage in three-stage enhanced low-dose scan of liver. Methods: From March 2017 to November 2017, two groups which each group included 50 patients were randomly selected at the Second Affiliated Hospital of Harbin Medical University with different stages of arterial phase, delayed phase and portal vein scanning. GE Discovery CT 750 HD Liver CT Ⅲ was used during enhanced scanning. A total of 100 patients included 56 males and 44 females, aged 27-73 years old and 42 patients with hepatocellular carcinoma, 44 patients with hepatic hemangioma, and 14 patients with other diseases. The arterial and delayed period of group A patients were scanned with a low dose of 100 kV+ASIR, and the portal vein phase was conventional. Dosage scanning was 120 kV+FPP; the arterial and delayed period of group B was normal dose scanning, 120 kV+FPP, and the portal vein phase was low dose scanning, 100 kV+ASIR. At the same time, FBP reconstruction was used for all low-dose scanning phases to obtain low-dose images under normal reconstruction mode. The objective evaluation index of image quality was analyzed by completely randomized design analysis of variance, and Dunnett-t test was used to compare the two groups. For the subjective evaluation part, the rank sum test of multiple groups was used. Results: ASIR combined with low tube voltage enhanced low dose scanning in the third phase of the liver, and the radiation dose decreased by 37% in the low dose group compared with the normal dose group. There was no statistically significant difference between the low dose group (100 kV+ASIR) and the normal dose group (120 kV+FPP) in subjective image quality evaluation (P>0.05); objective evaluation of image quality except for low dose(100 kV+ASIR) portal stage noise slightly worse than conventional dose group (120 kV+FBP) (low dose 10.86±1.98, conventional dose 9.40±2.12, P<0.05), the other indexes in each period were superior or indifferent to the normal dose group. Conclusion: ASIR technique combined with low tube voltage can be used in the third phase of liver enhanced low-dose scanning and the image quality is improved.

Ratiometric fluorescent probes for selective and sensitive visualization of bacterial microenvironment protease activity

Two novel FRET probes for selective real-time ratiometric imaging of SspA activity in live S. aureus cells.

Rationally designed organelle-specific thermally activated delayed fluorescence small molecule organic probes for time-resolved biological applications

A new strategy for TADF-based probes to maintain long fluorescence emission lifetime in TRFI studies in cells was developed.

A coumarin-based dual optical probe for homocysteine with rapid response time, high sensitivity and selectivity

In this study, a new coumarin-based fluorescent and chromogenic dual channel probe (DC) was used for the selective detection of homocysteine (Hcy) over other amino acids, especially for cysteine (Cys) and glutathione (GSH). When Hcy is present in the solution, the remarkable fluorescence enhancement and obvious blue shift in UV-vis spectra can be observed. In addition, the color change from purple to yellow can be observed clearly by unaided eyes. This probe DC has fast response time, excellent sensitivity and selectivity to Hcy. A linear relationship exists between the ratio of emissions at 486 and 625 nm, and Hcy can be detected in a wide concentration range (0-200 μM). The signal-to-background ratio of fluorescence at 486 nm can reach 8.4, and the detection limit is calculated to be 3.5 µM. The response mechanism is proved to be the Michael addition reaction by Hcy. Preliminary results on cell imaging enable the practical application of Hcy tracing in living cells.

Cancer is not a risk factor for bullous pemphigoid: 10-year population-based cohort study

BACKGROUND

Bullous pemphigoid (BP) is the most common autoimmune bullous disease. Whether there is an increased risk for subsequent BP among patients with cancer is still unclear.

OBJECTIVES

To evaluate the risk for subsequent BP in patients with cancer.

METHODS

This nationwide population-based cohort study was based on data obtained from the Taiwan National Health Insurance Database between 2000 and 2011. A total of 36 838 patients with cancer and 147 352 age-, sex- and index-date-matched controls were recruited. The hazard ratio (HR) of subsequent BP in the patients with cancer was analysed using a Fine-Gray competing risk regression model with mortality as the competing event.

RESULTS

The incidence of BP per 100 000 person-years was 17·2 in the patients with cancer and 19·8 in the controls; therefore, the crude incidence rate ratio was 0·87 [95% confidence interval (CI) 0·53-1·36]. The HR of subsequent BP in the patients with cancer was 0·47 (95% CI 0·23-0·94) using the Fine-Gray competing risk regression model. Age (HR 1·05, 95% CI 1·03-1·07), diabetes mellitus (HR 1·69, 95% CI 1·10-2·59) and cerebrovascular disease (HR 2·14, 95% CI 1·36-3·34) were independent risk factors for BP.

CONCLUSIONS

The incidence of BP in patients with cancer was not higher than in the control group. Cancer is not a risk factor for BP.

[Drug resistance mutations and its associated factors among 579 HIV/AIDS patients experiencing failure of antiretroviral therapy in Jiangsu Province, China]

Objective: To understand the incidence and related factors of HIV-1 drug resistance among HIV/AIDS patients experiencing treatment failure in Jiangsu province, China. Methods: The HIV/AIDS integrated prevention and control data information management system of China were used to collect the basic data of patients, blood specimens were collected from patients who had antiretroviral therapy (ART) failure with ≥12 months and older than 18 years in 2016 in Jiangsu, excluding cases with missing information, 713 cases were enrolled in this study. HIV-1 RNA was extracted, and then pol gene region was amplified and sequenced. The obtain sequences were submitted to Stanford University HIV Drug Resistance Database to interpret and analyse HIV-1 drug resistance and sub-types. Multivariate logistic regression model was used to explore the related factors of drug resistance. Results: A total of 579 subjects were amplified successfully, male accounted for 85.66% (496 cases), and the median age was 39 years old. The main route of infection was sexual transmission (553 cases, 95.51%). A total of 331 patients with drug resistance gene mutation were detected, drug resistance mutation rate was 57.18%. Compared with patients with baseline CD4(+)T cell count >500 cells/μl, patients with CD4(+)T cell count in 201-500 cells/mm(3) and ≤200 cells/μl had a higher incidence of genetic drug resistance, the odds ratio was 3.33 and 6.87, respectively. Compared with patients with treatment less than 24 months, patients treated for 25-48 months had a higher incidence of drug resistance, the odds ratio was 1.88. Compared with patients infected by CRF07_BC strains, patients infected by CRF01_AE strains were associated with higher incidence of drug resistance, the odds ratio was 2.22 and 3.32, respectively. Protease inhibitor (PI) resistance mutations, nucleoside reverse transcriptase inhibitor (NRTI) and non-nucleoside reverse transcriptase inhibitor (NNRTI) were found in 3.80%, 33.16% and 53.37% of patients, respectively. 31.95% of patients harbored NRTI and NNRTI resistance mutations simultaneously. M184V/I and K103N/Q were the highest frequency of NRTI and NNRTI resistance mutation, the prevalence of M184V/I and K103N/Q were 28.15% and 22.28%, respectively. Conclusion: The status of HIV-1 drug resistance mutations are complex and diverse among patients experiencing failure of ART in Jiangsu. Patients with lower baseline CD4(+)T cell count, longer treatment time and HIV-1 CRF01_AE and B strains infection were associated with higher incidence of drug resistance mutation.

Fluorogen-activating proteins: beyond classical fluorescent proteins

Fluorescence imaging is a powerful technique for the real-time noninvasive monitoring of protein dynamics. Recently, fluorogen activating proteins (FAPs)/fluorogen probes for protein imaging were developed. Unlike the traditional fluorescent proteins (FPs), FAPs do not fluoresce unless bound to their specific small-molecule fluorogens. When using FAPs/fluorogen probes, a washing step is not required for the removal of free probes from the cells, thus allowing rapid and specific detection of proteins in living cells with high signal-to-noise ratio. Furthermore, with different fluorogens, living cell multi-color proteins labeling system was developed. In this review, we describe about the discovery of FAPs, the design strategy of FAP fluorogens, the application of the FAP technology and the advances of FAP technology in protein labeling systems.

A novel nitroreductase-enhanced MRI contrast agent and its potential application in bacterial imaging

Nitroreductases (NTRs) are known to be able to metabolize nitro-substituted compounds in the presence of reduced nicotinamide adenine dinucleotide (NADH) as an electron donor. NTRs are present in a wide range of bacterial genera and, to a lesser extent, in eukaryotes hypoxic tumour cells and tumorous tissues, which makes it an appropriate biomarker for an imaging target to detect the hypoxic status of cancer cells and potential bacterial infections. To evaluate the specific activation level of NTR, great efforts have been devoted to the development of fluorescent probes to detect NTR activities using fluorogenic methods to probe its behaviour in a cellular context; however, NTR-responsive MRI contrast agents are still by far underexplored. In this study, para-nitrobenzyl substituted T1-weighted magnetic resonance imaging (MRI) contrast agent Gd-DOTA-PNB (probe 1) has been designed and explored for the possible detection of NTR. Our experimental results show that probe 1 could serve as an MRI-enhanced contrast agent for monitoring NTR activity. The in vitro response and mechanism of the NTR catalysed reduction of probe 1 have been investigated through LC-MS and MRI. Para-nitrobenzyl substituted probe 1 was catalytically reduced by NTR to the intermediate para-aminobenzyl substituted probe which then underwent a rearrangement elimination reaction to Gd-DOTA, generating the enhanced T1-weighted MR imaging. Further, LC-MS and MRI studies of living Escherichia coli have confirmed the NTR activity detection ability of probe 1 at a cellular level. This method may potentially be used for the diagnosis of bacterial infections.

Aminoglycoside-based novel probes for bacterial diagnostic and therapeutic applications

Specific detection of pathogens has long been recognized as a vital strategy in the control of infectious diseases. Two novel theranostic neomycin analogs exhibit efficient targeting, labelling and killing of broad spectrum bacteria while not damaging macrophage-like cells. Furthermore, lipidated probe 2 clearly showed antibacterial activity against methicillin-resistant S. aureus.

[Effect of Electroacupuncture on Pain Reaction and Content of Proteinase-activated Receptors 2 in Dorsal Root Ganglion in Hyperalgesia Rats]

OBJECTIVE

To observe the effect of electroacupuncture (EA) on mechanical hyperalgesia threshold (MHTs) and thermal hyperalgesia threshold (THTs) and content of proteinase-activated receptors 2 (PAR 2) in dorsal root ganglia (DRG) in rats with inflammatory pain, so as to explore its peripheral mechanism underlying improvement of inflammatory pain.

METHODS

The present study contains two parts. 1) In the first part, 27 male SD rats were randomized into sham hyperalgesic priming (sham-HP) group and real hyperalgesic priming (HP) group (n＝5 in the sham-HP group and n＝6 in the HP group for the test of MHTs, n＝8 in the two groups for the test of THTs). The sham-HP model was established by subcutaneous injection of normal saline into the left plantar part of the hind-paw, and the HP model established by subcutaneous injection of 1% carragenan (the first injection) into the same left hind paw, followed by injection of PGE₂ (100 ng/25 μL, the second injection) into the dorsum pedis of the same hind paw 7 days after the first injection. The ipsilateral paw withdrawal latencies (MHTs and THTs) were detected before and 5 h, 3 d and 6 d after the first injection, 0.5, 4 and 24 h after the second injection. 2) In the second part, 64 male SD rats were randomly divided into sham-HP, HP, sham-EA and EA groups (n＝16 in each group). The sham-HP and HP models were made in the same way as the first part. Both"Zusanli"(ST 36)and "Kunlun"(BL 60) were punctured with filiform needles in the sham-EA group and also stimulated with EA: 2 Hz/100 Hz, 0.5－1.5 mA (0.5 mA increase per 10 min) for 30 min in the EA group, 1 time/d for 7 d. Both ipsilateral MHTs and THTs were observed at the same time-points of the first part and the PAR 2 protein content in the L 4－L 6 DRGs was assayed by ELISA 24 h after the second injection.

RESULTS

1) In the first part of the study, compared with the sham-HP group, the MHTs at 5 h and 3 d, and THT at 5 h after the first injection, and MHTs, and THTs at 4 and 24 h after the se-cond injection were significantly decreased in the HP group (P<0.01, P<0.05). 2) In the second part of the study, compared with the HP group, the MHTs at 4 and 24 h after the second injection and the THTs at 3 d after the first injection, 4 and 24 h after the second injection were significantly up-regulated in the EA group (P<0.01, P<0.05). The content of PAR 2 in the DRGs (L 4－L 6) was significantly higher in the HP group than in the sham-HP group (P<0.05), but considerably lower in the EA group than in the HP group (P<0.05).

CONCLUSION

EA can suppress hyperalgesia priming in inflammatory pain rats which may be related to its effect in down-regulating PAR 2 level in the lumbar DRGs.

Gadolinium-Labeled Aminoglycoside and Its Potential Application as a Bacteria-Targeting Magnetic Resonance Imaging Contrast Agent

Magnetic resonance imaging (MRI) is a powerful diagnostic technique that can penetrate deep into tissue providing excellent spatial resolution without the need for ionizing radiation or harmful radionuclides. However, diagnosing bacterial infections in vivo with clinical MRI is severely hampered by the lack of contrast agents with high relaxivity, targeting capabilities, and bacterial penetration and specificity. Here, we report the development of the first gadolinium (Gd)-based bacteria-specific targeting MRI contrast agent, probe 1, by conjugating neomycin, an aminoglycoside antibiotic, with Dotarem (Gd-DOTA, an FDA approved T₁-weighted MRI contrast agent). The T₁ relaxivity of probe 1 was found to be comparable to that of Gd-DOTA; additionally, probe 1-treated bacteria generated a significantly brighter T₁-weighted MR signal than Gd-DOTA-treated bacteria. More importantly, in vitro cellular studies and preliminary in vivo MRI demonstrated probe 1 exhibits the ability to efficiently target bacteria over macrophage-like cells, indicating its great potential for high-resolution imaging of bacterial infections in vivo.