Circular olefin copolymers made de novo from ethylene and α-olefins.

Ethylene/α-olefin copolymers are produced in huge scale and widely used, but their after-use disposal has caused plastic pollution problems. Their chemical inertness made chemical re/upcycling difficult. Ideally, PE materials should be made de novo to have a circular closed-loop lifecycle. However, synthesis of circular ethylene/α-olefin copolymers, including high-volume, linear low-density PE as well as high-value olefin elastomers and block copolymers, presents a particular challenge due to difficulties in introducing branches while simultaneously installing chemical recyclability and directly using industrial ethylene and α-olefin feedstocks. Here we show that coupling of industrial coordination copolymerization of ethylene and α-olefins with a designed functionalized chain-transfer agent, followed by modular assembly of the resulting AB telechelic polyolefin building blocks by polycondensation, affords a series of ester-linked PE-based copolymers. These new materials not only retain thermomechanical properties of PE-based materials but also exhibit full chemical circularity via simple transesterification and markedly enhanced adhesion to polar surfaces.

Multicenter evaluation of a simple and sensitive nucleic acid self-testing for SARS-CoV-2.

A rapid and accurate COVID-19 diagnosis is a prerequisite for blocking the source of infection as soon as possible and taking the appropriate medical action. Herein, we developed GeneClick, a device for nucleic acid self-testing of SARS-CoV-2, consisting of three modules: a sampling kit, a microfluidic chip-based disposable cartridge, and an amplification reader. In addition, we evaluated the clinical performance of GeneClick using 2162 nasal swabs collected at three medical institutions, using three commercial RT-qPCR kits and an antigen self-test as references. Compared to RT-qPCR, the sensitivity and specificity of the GeneClick assay were 97.93% and 99.72%, respectively, with a kappa value of 0.979 (P â€‹< â€‹0.01). Of the 2162 samples, 2076 were also tested for SARS-CoV-2 antigens. Among the 314 positive samples identified by GeneClick assay, 63 samples were undetected by antigen tests. Overall, the GeneClick nucleic acid self-test demonstrated higher accuracy than the antigen-based detection. Based on the additional features, including simple operation, affordable price, portable device, and reliability of smartphone APP-driven sampling and result reporting, GeneClick offers a powerful tool for field-based SARS-CoV-2 detection in primary healthcare institutions or at-home use.

Histiocytoid giant cellulitis-like Sweet syndrome at the site of sternal aspiration: A case report and review of literature.

BACKGROUND: Giant cellulitis-like Sweet syndrome (SS) is a rare subtype of SS, and reports of the combined histiocytoid type of pathology are scarce. Here, we report a case of SS with distinctive clinical presentations and which was difficult to distinguish from cellulitis. By sharing this case and a discussion of the related literature in detail, we aim to provide clinicians with new insights into the characteristics of histiocytoid giant cellulitis-like (HGC)-SS and the pathogenesis of SS. CASE SUMMARY: A 52-year-old male was admitted after experiencing progressive fatigue for 1 mo and tongue swelling with pain for 1 d. He was diagnosed with myelodysplastic syndrome (MDS) and angioneurotic edema of the tongue and floor of the mouth. However, 7 d after examination by sternal aspiration, a violaceous, tender, and swollen nodule developed at the site, with poorly demarcated erythema of the surrounding skin. Considering his profile of risk factors, the diagnosis of cellulitis was made and he was administered broad-spectrum antibiotics. When the lesion continued to worsen and he developed chills and fever, pathogenic and dermatopathological examination led to the diagnosis of HGC-SS. Treatment with prednisone led to the fever being relieved within 24 h and the skin lesion being resolved within 1 wk. The patient refused intensive treatment and was instead given thalidomide, erythropoietin, stanozolol, and supportive care. The prednisone was gradually tapered, with no signs of recurrence, but he died 2 mo later of severe pneumonia. CONCLUSION: HGC-SS demonstrates unique manifestation. SS and leukemia cutis share cytological origin. Myelofibrosis and SS are adverse prognostic factors for MDS.

Dimeric-(-)-epigallocatechin-3-gallate inhibits the proliferation of lung cancer cells by inhibiting the EGFR signaling pathway.

Non-small cell lung cancer (NSCLC) is one of the most general malignant tumors. The overexpression of epidermal growth factor receptor (EGFR) is a common marker in NSCLC, and it plays an important role in the proliferation, invasion, and metastasis of cancer cells. At present, drugs developed with EGFR as a target suffer from drug resistance, so it is necessary to study new compounds for the treatment of NSCLC. The active substance in green tea is EGCG, which has anti-cancer effects. In this study, we synthesized dimeric-(-)-epigallocatechin-3-gallate (prodelphinidin B-4-3,3‴-di-O-gallate, PBOG), and explored the effect of PBOG on lung cancer cells. PBOG can inhibit the proliferation and migration of NCI-H1975 cells, promote cell apoptosis, and inhibit cell cycle progression. In addition, PBOG can bind to the EGFR ectodomain protein and change the secondary structure of the protein. At the same time, PBOG decreases the expression of EGFR and downstream protein phosphorylation. Animal experiments confirmed that PBOG can inhibit tumor growth by inhibiting EGFR phosphorylation. Collectively, our study results show that PBOG may induce a decrease in intracellular phosphorylated EGFR expression by binding to the EGFR ectodomain protein, thereby inducing apoptosis and inhibiting cell cycle progression, thus providing a new strategy to treat lung cancer.

Detection of low-load Epstein-Barr virus in blood samples by enriched recombinase aided amplification assay.

Epstein-Barr virus (EBV), a common human γ-herpesvirus, infects more than 90% of adults worldwide. The purpose of this study was to establish a novel EBV detection method by combining the recombinase aided amplification (RAA) assay with an initial enrichment step that utilizes magnetic beads coated with a recombinant human mannan-binding lectin (rhMBL, M1 protein). An M1 protein-protein A magnetic bead complex (M1 beads) was prepared and used to achieve separation and enrichment of EBV from blood. After nucleic acid extraction, DNA was amplified by RAA. Using 388 whole blood samples and 1 serum sample, we explored the specificity, sensitivity and applicability of the newly developed detection method and compared it with commercial quantitative real-time polymerase chain reaction (qPCR) following M1 bead enrichment, traditional qPCR and traditional RAA. After enrichment, the positivity rate of EBV was increased from 15.94% to 17.74% by RAA (P < 0.05) and from 7.20% to 15.17% by qPCR (P < 0.05). The viral loads after enrichment were increased by 1.13 to 23.19-fold (P < 0.05). Our data demonstrates that an RAA assay incorporating M1 bead enrichment is a promising tool for detecting low EBV viral loads in blood samples that will facilitate an early response to EBV infection.

Discovery of EGFR-Targeted Environment-Sensitive fluorescent probes for cell imaging and efficient tumor detection.

Overexpression of human epidermal growth factor receptor (EGFR) plays an important role in several signaling pathways inside and outside the cell, especially in the processes of cell proliferation, differentiation, and death in various cancers. Due to the complexity of the structure and function of EGFR, research on the fluorescence visualization of EGFR protein visualization has proved challenging. One possible strategy for designing a receptor-targeting fluorescent probe with a switching mechanism is to introduce an environment-sensitive fluorophore into the drug ligand. Based on this strategic molecular design, we introduced two environment-sensitive small molecular fluorophores, dansyl chloride (DNS) and nitrobenzoxadiazole (NBD), to replace the morpholine group of gefitinib, achieving a series of fluorescent molecular probes bearing a switching mechanism. The GN probes exhibited prominent environment sensitivity, suggesting good performance as turn-on EGFR-targeting fluorescent ligands. The representative probe GN3 specifically responded to tumor cells overexpressing EGFR, which was validated with live-cell fluorescence imaging and in vivo xenograft tumor imaging. Ligand-induced EGFR phosphorylation in A431 cells was considerably inhibited by probe GN3, demonstrating that this probe still functions as an EGFR inhibitor. Owing to the turn-on response of GN3 to EGFR in tumor cells, and the competitive replacement behavior to the EGFR inhibitor gefitinib, these probes have the potential to be used for fluorescence imaging of cells overexpressing EGFR.

Synthesis and in vitro biological evaluation of novel dendrocandin analogue as potential anti-tumor agent.

Dendrocandins are characteristic chemical structures of D. officinale and have strong physiological bioactivities. In this study, a dendrocandin analogue (1) has been prepared by total synthesis (9 steps, 12.6% overall yield) in which coupling reaction and Wittig reaction as the key steps. Compound 1 was also evaluated for its anticancer activity in vitro against six human cancer cells (MCF-7, A549, A431, SW480, HepG-2 and HL-60) using MTT assays. Compound 1 showed potent cytotoxicity, with the IC50 value 16.27 ± 0.26 µM. The expression levels of apoptotic proteins indicated that compound 1 can up-regulate the expression of apoptotic proteins, leading to apoptosis. This compound suggested that it's potential as anticancer agent for further development.

The association of myopia progression with the morphological changes of optic disc and ß-peripapillary atrophy in primary school students.

PURPOSE: To study the association of myopia progression with the morphological changes of optic disc and ß-peripapillary atrophy (ß-PPA) in 8-11 years old primary school students. METHODS: This study was a prospective, school-based investigation. This study included 610 children (1008 eyes) who were continuously observed and had data available from 2016 to 2017 in the Sanhe Cohort Study of the Risk Factors for Myopia (SCSRFM). The children underwent a comprehensive eye examination including measurement of visual acuity, autorefractometry, and posterior segment of the eye. ß-PPA regions and optic disc ovality index were identified and measured on the fundus photographs. RESULTS: The prevalence of myopia was 72.62% (732/1008) in 2016. In myopic children, the prevalence of the vertical ß-PPA, the horizontal ß-PPA, and the oval optic disc were 75.68% (554/732), 75.96% (556/732) and, 11.61% (85/732) respectively. From 2016 to 2017, with the progression of vertical ß-PPA, horizontal ß-PPA, area of ß-PPA, and optic disc ovality index, the myopic diopter and the axial length (AL) were increased. The progression of horizontal ß-PPA was significantly correlated with the progression of myopic diopter and AL (all p < 0.05). The analysis on the distribution of progression rate of parameters in different groups found that the progression rate of horizontal ß-PPA, area of ß-PPA, and optic disc ovality index increased with the increase of the progression of diopter and AL. The progression of horizontal ß-PPA, area of ß-PPA, optic disc ovality index, and diopter in girls were greater than that in boys, and the progression of optic disc ovality index and diopter had a statistical significance (all p < 0.05). CONCLUSIONS: The 1-year follow-up study of the third-grade primary school students showed that with the progression of myopia and the growth of AL, ß-PPA and optic disc ovality index also changed. There was a positive correlation between the change of ß-PPA and optic disc ovality index and the progression of myopia diopter and AL.

Direct copolymerization of ethylene with protic comonomers enabled by multinuclear Ni catalysts.

Ethylene/polar monomer coordination copolymerization offers an attractive way of making functionalized polyolefins. However, ethylene copolymerization with industrially relevant short chain length alkenoic acid remain a big challenge. Here we report the efficient direct copolymerization of ethylene with vinyl acetic acid by tetranuclear nickel complexes. The protic monomer can be extended to acrylic acid, allylacetic acid, ω-alkenoic acid, allyl alcohol, and homoallyl alcohol. Based on X-ray analysis of precatalysts, control experiments, solvent-assisted electrospray ionization-mass spectrometry detection of key catalytic intermediates, and density functional theory studies, we propose a possible mechanistic scenario that involves a distinctive vinyl acetic acid enchainment enabled by Ni···Ni synergistic effects. Inspired by the mechanistic insights, binuclear nickel catalysts are designed and proved much more efficient for the copolymerization of ethylene with vinyl acetic acid or acrylic acid, achieving the highest turnover frequencies so far for both ethylene and polar monomers simultaneously.

Long-Term Effect of Early Post-operative Transcutaneous Electrical Stimulation on Voiding Function After Radical Hysterectomy: A Multicenter, Randomized, Controlled Trial.

Introduction: Post-radical-hysterectomy (RH) patients suffer from a series of problems resulting from neurovascular injury, such as bladder dysfunction, which reduce their quality of life. We have designed this study to evaluate the efficacy of transcutaneous electrical stimulation (TENS) on patient rehabilitation after RH for early cervical cancer. Materials and methods: A total of 97 patients were enrolled in a randomized-controlled trial (from January 2015 to December 2019) involving 7 medical centers nationwide. Patients were assigned to either the intervention group (n = 46), or the control group (n = 51). TENS was given to patients in the intervention group from the 7th day after surgery for a total of 14-21 days. The control group received no TENS. Primary outcomes were measured for residual urine volume and recovery of urination function. Secondary outcomes were measures for urodynamics (UDS), pelvic floor electromyography function examination (PFEmF), and quality of life (QoL). Results: Residual urine volume and improvement in the rate of urination were found to show no significant differences on the 14th, 21st, and 28th days after surgery. The maximum flow rate (Qmax) in the intervention group was significantly higher than that in the control group on the 28th day, but there were no significant differences in average flow rate, voiding time, time to Qmax, muscle fiber strength, muscle fiber fatigue, and the abnormal rate of A3 reflection on the 28th day and the 3rd mo., as well as in the QoL at 3rd mo., 6th mo., and 12th mo. after surgery. Conclusion: Our study showed no sufficient evidence to prove that TENS under the trialed parameters could improve the subject's voiding function, PFEmF, and QOL after RH. This has provided valuable data for rehabilitation after RH. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02492542.

The effect of retaining intact posterior capsule in congenital cataract surgery in children aged 4-8 years.

BACKGROUND: The present study sought to observe the effect of retaining intact posterior capsule in congenital cataract surgery in children aged 4-8 years. METHODS: This is a retrospective case control study. Seventy-seven children (130 eyes) aged from 4 to 8 years who underwent cataract surgery were divided into two groups. In Group A, 50 eyes underwent phacoemulsification, intraocular lens implantation and posterior capsule capsulotomy combined with anterior vitrectomy. In Group B, 80 eyes underwent cataract phacoemulsification and intraocular lens implantation. The postoperative visual acuity and the rate of complications were compared. RESULTS: In all patients, cataract surgeries were performed evenly without intraoperative complications. The follow-up time ranged from 6 months to 42 months. No apparent visual axis opacity was detected in group A during the follow-up. By the last visit, apparent visual axis opacity was detected in 31 eyes (38.75%) in group B. Among them, 9 eyes (29.03%) with mild posterior capsule opacification (PCO) were treated with Nd:YAG laser, 3 eyes (9.68%) with thick proliferative membranes were treated with posterior capsule capsulotomy combined with anterior vitrectomy and proliferative membranes in 19 eyes (61.29%) were completely aspired and the posterior capsule was retained. During follow-up, only 2 (6.45%) eyes had PCO recurrence and were treated with Nd:YAG laser. The visual acuity was significantly higher than that before surgery in all patients. CONCLUSIONS: For older children, the incidence of PCO will be low even if intact posterior capsule is retained. Either Nd:YAG laser or surgical treatment for PCO will be able to maintain good vision.

Effect of lens capsular tension ring on preventing capsular contraction syndrome in the surgery of retinitis pigmentosa combined with cataract: Retrospective case series.

PURPOSE: To observe the effect of phacoemulsification and intraocular lens (IOL) implantation with or without lens capsular tension ring (CTR) on retinitis pigmentosa (RP) combined with cataract patients. DESIGN: Retrospective cases series study. METHODS: Sixty-three cases (84 eyes) of RP with cataract were collected, including 30 males and 33 females. Phacoemulsification with 3.0 mm clear corneal incision was performed in all the patients. IOL and CTR implantation were performed in 44 eyes, and IOL implantation alone was performed in 40 eyes. All cases were followed up at 1 day, 1 week and 1, 3, 6,12 months after the surgery to compare the best-corrected visual acuity (BCVA), intraocular pressure (IOP), corneal endothelial cell count (ECC) and complications before and after the surgery. RESULTS: All surgery were successfully completed by the same physician, and IOL and CTR were all implanted in capsule without complications. The BCVA at 6 months after surgery was 0.91 ± 0.88 LogMAR, showing an improvement compared with the BCVA(1.3 ± 0.7LogMAR) before surgery and there was a statistically significant difference (P = .003). Four cases of capsule contraction syndrome (CCS) occurred in no CTR implantation group and there was no CCS in CTR group. There was a statistically significant difference in the incidence of CCS between two groups (P = .047). CONCLUSIONS: Phacoemulsification for RP combined with cataract is safe and reliable, and CTR implantation is conducive to reducing the complications caused by capsule contraction.

Microscale endometrial sampling biopsy in detecting endometrial cancer and atypical hyperplasia in a population of 1551 women: a comparative study with hysteroscopic endometrial biopsy.

BACKGROUND: Endometrial cancer is one of the most common malignancies of the reproductive system. Effective and cost-effective screening method for populations at high risk is not available. This study aimed to investigate specimen adequacy and the influencing factors in microscale endometrial sampling biopsy and to evaluate the diagnostic accuracy and medical cost of biopsy in endometrial cancer and atypical hyperplasia screenings in comparison with hysteroscopic endometrial biopsy. METHODS: A total of 1551 patients at high risk for endometrial lesions who required hysteroscopic endometrial biopsy from November 2017 to August 2018 were included. Microscale endometrial sampling biopsy was performed, followed by hysteroscopic endometrial biopsy. We evaluated the specimen adequacy and influencing factors of microscale endometrial sampling. Diagnostic consistency between microscale endometrial sampling biopsy and hysteroscopic endometrial biopsy was evaluated. The sensitivity, specificity, positive predictive value, and negative predictive value of microscale endometrial sampling biopsy in screening for endometrial cancer and atypical hyperplasia were analyzed, and the medical costs of the two procedures were compared. RESULTS: The specimen adequacy was 81.2%. Patient age, menopausal status, endometrial thickness, and endometrial lesion type were correlated with specimen adequacy. There was good consistency in distinguishing benign and malignant endometrial diseases between microscale endometrial sampling biopsy and hysteroscopic biopsy (kappa 0.950, 95% CI 0.925-0.975). The sensitivity, specificity, positive predictive value, and negative predictive value of microscale endometrial sampling biopsy were 91.7%, 100.0%, 100.0%, and 99.3% for endometrial cancer screening, respectively, and 82.0%, 100.0%, 100.0%, and 99.4% for atypical hyperplasia screening. The medical cost of endometrial sampling biopsy was only 22.1% of the cost of hysteroscopic biopsy. CONCLUSIONS: Microscale endometrial sampling biopsy is a minimally invasive alternative technique for obtaining adequate endometrial specimens for histopathological examination. It has the potential to be used in detecting endometrial cancer and atypical hyperplasia with high efficiency and low cost.

Urodynamic assessment of bladder storage function after radical hysterectomy for cervical cancer.

BACKGROUND: After radical hysterectomy for cervical cancer, the most common complication is lower urinary tract symptoms. Post-operatively, bladder capacity can alter bladder function for a prolonged period. This study aimed to identify factors affecting bladder storage function. METHODS: A multicenter, retrospective cohort study was conducted. Information of patients with stages IA2 to IIB cervical cancer with urodynamic study results were retrospectively collected from nine hospitals between June 2013 and June 2018 according to the inclusion criteria. Demographic, surgical, and oncological data were collected. The univariate and multivariate logistic regression was used to identify clinical factors associated with bladder storage function. RESULTS: Two hundred and three patients with cervical cancer had urodynamic testing post-operatively. Ninety-five (46.8%) patients were diagnosed with stress urinary incontinence (SUI). The incidence of low bladder compliance (LBC) was 23.2%. Twenty-seven (13.3%) patients showed detrusor overactivity (DO). Fifty-seven patients (28.1%) presented with a decreased maximum cystometric capacity (DMCC). The probability of composite bladder storage dysfunction was 68.0%. Multivariate analysis confirmed that laparoscopy represents a protective factor for SUI with an odds ratio of 0.498 (P = 0.034). Patients who underwent a nerve-sparing procedure were less odds to experience SUI (P = 0.014). A significant positive correlation between LBC and DO was observed (P < 0.001). A greater length of the resected vagina and chemoradiotherapy were common risk factors for LBC and DO, while radiotherapy exerted a stronger effect than chemotherapy. Additionally, patients who received chemoradiotherapy frequently developed a DMCC. The follow-up time was not correlated with bladder storage function. CONCLUSION: A nerve-sparing procedure without longer resected vagina is recommended for protecting the bladder storage function.

The high expression of the pain-related inflammatory factors in the eyes of cataract patients infected with hepatitis B virus.

In cataract surgery, it is often found that patients infected hepatitis B virus (HBV) are likely to suffer from more pain than other patients. In order to assess the inflammation status of the aqueous humor in the eyes of cataract patients infected with HBV. RayBio Human Inflammation Array was used to assay aqueous humor samples collected from 14 eyes of patients infected with HBV and 14 eyes of cataract patients without HBV infection (the controls) during the cataract surgery. RayBio Human Quantibody Cutom Array was adopted for the validation of the screened cytokines, with aqueous humor samples collected from 40 eyes of patients infected with HBV and 40 eyes of the controls. A pain questionnaire survey about the surgery was conducted in all patients after operation. The results of questionnaire showed that patients infected with HBV were more likely to have pain during operation. The Human Inflammation Array revealed that the expression levels of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor α (TNF-α) and tumor necrosis factor ß (TNF-ß) were very high in HBV infected patients and IL-1ra was much lower in patients infected with HBV (all, P < 0.05). In validation, the Human Quantibody Cutom Array revealed that the expression levels of MCP-1 and TNF-α were high in HBV infected patients with significant difference (all P < 0.05). These results revealed that pain-related inflammatory factors MCP-1 and TNF-α were increased in aqueous humor of cataract patients infected with HBV, which indicates that patients infected with HBV may be more prone to intraoperative pain.

A Versatile Enantioselective Catalytic Cyclopropanation-Rearrangement Approach to the Divergent Construction of Chiral Spiroaminals and Fused Bicyclic Acetals.

A highly enantioselective synthesis of various chiral heterobicyclic molecules including spiroaminals and fused bicyclic acetals has been developed via a chiral copper catalyzed cyclopropanation-rearrangement (CP-RA) approach under mild reaction conditions. Remarkably, the asymmetric CP-RA for exocyclic vinyl substrates without a pro-stereogenic carbon at the ß-position has been realized for the first time and a broad substrate scope with excellent results (33 examples; 34-99 % yields; >95/5 dr and 91-99 % ee) has been achieved. An application of a successive enantioselective CP-RA approach was also described, providing a concise access to complex chiral heteropolycycles.

The expression of cytokines in aqueous humor of high myopic patients with cataracts.

Purpose: To analyze the expression of 440 human cytokines in aqueous humor of high myopic patients with cataracts. Methods: Eighty-five patients with cataracts were recruited in this study. In the screening stage, the RayBio G-Series Human Cytokine Antibody Array 440 was used to assay the aqueous humor samples collected from nine high myopic patients with cataracts and eight non-myopic patients with cataracts right before the surgery. The array was further used for verification of the screened cytokines, with aqueous humor samples obtained from 34 eyes of high myopic patients with cataracts and 34 eyes of non-myopic patients with cataracts. Results: Compared with the non-myopic patients with cataracts, the expression levels of decorin, receptor activator of NF-kB (RANK), angiopoietin-1 (ANG-1), C-X-C motif ligand 16 (CXCL16), ß-inducible gene-h3 (bIG-H3), insulin-like growth factor-binding protein 2 (IGFBP-2), and interleukin-17B (IL-17B) were statistically significantly higher in high myopic patients with cataracts (all p<0.000114). The matrix metalloproteinase-2 (MMP-2) level also increased in the aqueous humor of high myopic patients with cataracts (p = 0.0034). The concentrations of ANG-1 and MMP-2 were also increased in the aqueous humor of the confirmatory stage (all p<0.05). Conclusions: In this study, numerous cytokines in aqueous humor were detected in high myopic patients with cataracts and non-myopic patients with cataracts, and it was confirmed that the MMP-2 level in the aqueous humor of patients with high myopia was statistically significantly increased. Further verification also revealed the elevation of ANG-1 in the aqueous humor of high myopic patients with cataracts, which suggests that ANG-1 may be related to the pathogenesis of high myopia.