Co-exposure of arsenic and polystyrene-nanoplastics induced kidney injury by disrupting mitochondrial homeostasis and mtROS-mediated ferritinophagy and ferroptosis.

Arsenic (As) and polystyrene nanoplastics (PSNPs) co-exposure induced biotoxicity and ecological risks have attracted wide attention. However, the combined effects of As and PSNPs on the kidney and their underlying mechanisms of toxicities remain to be explored. Here, we investigated the effects of As and PSNPs co-exposure on structure and function in mice kidney, and further explored the possible mechanisms. In this study, we identified that co-exposure to As and PSNPs exhibited conspicuous renal structural damage and pathological changes, accompanied by renal tissue fibrosis (increased protein expression of Collagen I and α-SMA and deposition of collagen fibers), whereas alone exposure to As or PSNPs does not exhibit nephrotoxicity. Subsequently, our results further showed that combined action of As and PSNPs induced mitochondrial oxidative damage and impaired mitochondrial dynamic balance. Furthermore, co-treatment with As and PSNPs activated NCOA4-mediated ferritinophagy and ferroptosis in mice kidney and TCMK-1 cells, which was confirmed by the changes in the expression of ferritinophagy and ferroptosis related indicators (NCOA4, LC3, ATG5, ATG7, FTH1, FTL, GPX4, SLC7A11, FSP1, ACSL4 and PTGS2). Meaningfully, pretreatment with the mtROS-targeted scavenger Mito-TEMPO significantly attenuated As and PSNPs co-exposure induced mitochondrial damage, ferritinophagy and ferroptosis. In conclusion, these findings demonstrated that mtROS-dependent ferritinophagy and ferroptosis are important factors in As and PSNPs co-exposure induced kidney injury and fibrosis. This study provides a new insight into the study of combined toxicity of nanoplastics and heavy metal pollutants.

Modified adenoid grading system for evaluating adenoid size in children: a prospective validation study.

Nasal endoscopy is the best choice for evaluation of adenoid size, but very few studies published on the endoscopic quantitative assessment. This study aimed to newly propose and validate a modified adenoid grading system (MAGS) with the existing endoscopic scoring methods of adenoid size. A prospective study on children with chronic mouth breathing and having endoscopic nasal examination was conducted. Digital images obtained during endoscopic examination were evaluated with the traditional method and the MGAS. Adenoid size was also evaluated by intraoperative nasal endoscopy among those underwent adenoidectomy. One hundred and thirty patients were enrolled. The MAGS showed high inter-rater reliability with a Kappa score of 0.869. Sixty of 130 patients underwent adenoidectomy and assessed with intraoperative nasal endoscopy. The MAGS significantly correlated to the percentage of nasopharyngeal obstruction of intraoperative endoscopy (Spearman's r = 0.796, gamma coefficient = 0.94), and the percentage of choanal obstruction of preoperative endoscopy (Spearman's r = 0.816, gamma coefficient = 0.859). Our findings suggest that the MAGS has high reliability and validity for assessment of adenoid size. It may be a more suitable and reliable grading system for endoscopic evaluation of adenoid size.

Fabrication of a cycloalkyl-monolith for on-line solid-phase extraction and determination of four polyphyllins in plasma.

A cycloalkyl-based polymer monolithic column for solid-phase extraction was prepared via radical polymerization using cyclohexyl methacrylate as the monomer. The preparative conditions such as crosslinker/monomer ratio and the amount of the porogens were optimized and the resulting monoliths were characterized by scanning electron microscopy and nitrogen adsorption-desorption method. On-line solid-phase extraction-high-performance liquid chromatography was performed to quantitatively analyse polyphyllin I, II, VI and VII contained in herbal medicine of paridis rhizome in mouse plasma using the homemade optimized monolithic SPE column combined with a C18 column, in which water was used to remove the plasma matrix while the polyphyllins in the mouse plasma were eluted by acetonitrile-water (42:58, V/V). Results obtained from the method validation show that the present method is feasible for the quantitative analysis of the four polyphyllins in plasma. The developed method was further applied for the real mouse plasma sample. These results show that the homemade cycloalkyl-based polymer monolithic SPE column has good ability for clean-up of the interfering bio-matrix and simultaneously extracting the four polyphyllins from mouse plasma. Furthermore, the present method is a promising method for quantitative determination of saponins compounds from complex bio-samples with the advantages of simple and efficient.

Fabrication of an ionic-liquid-based polymer monolithic column and its application in the fractionation of proteins from complex biosamples.

An ionic-liquid-based polymer monolithic column was synthesized by free radical polymerization within the confines of a stainless-steel column (50 mm × 4.6 mm id). In the processes, ionic liquid and stearyl methacrylate were used as dual monomers, ethylene glycol dimethacrylate as the cross-linking agent, and polyethylene glycol 200 and isopropanol as co-porogens. Effects of the prepolymerization solution components on the properties of the resulting monoliths were studied in detail. Scanning electron microscopy, nitrogen adsorption-desorption measurements, and mercury intrusion porosimetry were used to investigate the morphology and pore size distribution of the prepared monoliths, which showed that the homemade ionic-liquid-based monolith column possessed a relatively uniform macropore structure with a total macropore specific surface area of 44.72 m2 /g. Compared to a non-ionic-liquid-based monolith prepared under the same conditions, the ionic-liquid-based monolith exhibited excellent selectivity and high performance for separating proteins from complex biosamples, such as egg white, snailase, bovine serum albumin digest solution, human plasma, etc., indicating promising applications in the fractionation and analysis of proteins from the complex biosamples in proteomics research.

Non-enzymatic electrochemical glucose sensor based on monodispersed stone-like PtNi alloy nanoparticles.

Monodisperse stone-like PtNi alloy nanoparticles (NPs) were synthesized at room temperature using an inverse microemulsion method. The results of XRD, HRTEM, and EDS demonstrate that these NPs consist of a disordered alloy that has (a) a face-centered cubic structure, (b) Pt/Ni atomic ratios of ∼5:1, and (c) a large number of atoms exposed on the NP surface and enclosed by low index facets. The material was placed on a glassy electrode which then displayed superior response to glucose. Best operated at a potential of 0.43 V (vs. SCE), the electrode has the following features: (a) a wide linear range (from 0.5 mM to 40 mM), (b) rapid response (<1 s), (c) a low detection limit (0.35 µM) and (d) a sensitivity of 40.17 µA mM-1cm-2). The NP sensor also is fairly selective over ascorbic acid, uric acid and fructose. The sensor has repeatability and durability for up to 30 days after manufacture. Graphical abstract Non-enzymatic glucose sensor based on a glassy carbon electrode modified with PtNi-NPS enclosed by low index facets. The sensor exhibits excellent features towards detecting glucose.

Separation of proteins from complex bio-matrix samples using a double-functionalized polymer monolithic column.

A double-functionalized polymer monolithic column was fabricated within the confines of a stainless-steel column (50 mm × 4.6 mm i.d.) via a facile method using iron porphyrin, ionic liquid (1-allyl-3-methylimidazolium chloride) and 1,10-decanediol dimethacrylate as tri-monomers; ethylene dimethacrylate as a crosslinker; polyethylene glycol 400 and N,N-dimethylformamide as co-porogens; benzoyl peroxide and N,N-dimethyl aniline as the redox initiation system. Results obtained from scanning electron microscopy, nitrogen adsorption-desorption, and mercury intrusion porosimetry confirmed the uniform pore structure and the pore size distribution of macro-pores. The home-made monolith was further characterized by elemental analysis to investigate the elemental composition of Fe supplied by iron porphyrin, confirming the synthetic process. The resulting optimized monolithic column was used as the stationary phase in high performance liquid chromatography for separating proteins, such as mixture of standard proteins, egg white, and human plasma, exhibiting good selectivity and high performance. It is worth noting that the home-made double-functionalized polymer monolithic column shows excellent selectivity for fractionation separation of human plasma proteins, and it is a promising separation tool for complex bio-samples in proteomic research.

The novel human ß-defensin 114 regulates lipopolysaccharide (LPS)-mediated inflammation and protects sperm from motility loss.

Lipopolysaccharide (LPS) is an important pathological factor involved in serious inflammatory diseases and male reproductive impairments. Emerging evidence demonstrates that antimicrobial peptides possess protective activity in response to LPS-induced inflammation. However, the LPS-binding and/or immunosuppressive activity of ß-defensins (DEFBs) has been underestimated. In the present work, we characterized a novel human defensin, DEFB114, which was expressed predominantly in the epididymis and gingival cells at the RNA level. Homogenous recombinant DEFB114 peptides were prepared and characterized using mass spectrometry. DEFB114 protein exhibited a broad spectrum of antimicrobial activity with salt sensitivity against typical pathogenic microbes (i.e. Escherichia coli, Staphylococcus aureus, and Candida albicans). Interestingly, DEFB114 demonstrated novel LPS-binding activity in vitro and inhibited TNF-α release in RAW264.7 cultures through the inhibition of MAPK p42/44 when challenged with LPS. Moreover, DEFB114 could also rescue the LPS-induced reduction of human sperm motility in vitro and protect d-galactosamine-sensitized C57BL/6 mice from LPS-induced lethality in vivo. The protective activity of DEFB114 on RAW264.7, human sperm, and the d-galactosamine-sensitized mice was disulfide bond-dependent because alkylated DEFB114 lost its activity. The low cytotoxicity of the DEFB114 peptide toward human erythrocytes is indicative of its potential therapeutic use in the treatment of LPS-induced inflammation, LPS contamination, and potentially septic shock.

Preparation of a novel MOF-POPM and its application in online purification and enrichment of oleanolic acid in medicinal plants.

In present work, a method for enrichment, purification, and content determination of oleanolic acid (OA) in medicinal plants was established based on on-line solid phase extraction (SPE). A metal organic frameworks-porous organic polymer monolith (MOF-POPM) was prepared with functionalized UiO-66-(OH)2 as monomer and was used as SPE column for online enrichment and purification of OA. The ratio of adsorbent, enriching and eluting solvent, mobile phase pH, and flow rate had been systematically investigated. Under the optimum conditions, the linear range of OA was 0.59-2500 µg/mL with r = 0.9996. The limit of detection (LOD) was 0.18 µg/mL and the limit of quantification (LOQ) was 0.59 µg/mL. The intra-day relative standard deviations (RSDs) and inter-day RSDs of retention time and peak area were less than 0.3% and 1.3%, respectively. The average recoveries of OA in medicinal plants samples ranged from 87.7 to 104.6%. The results demonstrated that the online system was reliable and accurate for enrichment, purification, and content determination of OA in medicinal plants.

Fabrication of a bio-based polymer adsorbent and its application for extraction and determination of glycosides from Huangqi Liuyi decoction.

Huangqi Liuyi Decoction, a famous classical Chinese prescription, shows significant curative effect on diabetes and its complications, in which calycosin-7-glucoside, liquiritin and glycyrrhizic acid are the main components that playing these mentioned pharmacological activity, under the synergistic action of various other ingredients in the decoction. However, there are significant differences in the content of active compounds in Chinese medicinal materials, which mainly due to origin, picking seasons, and processing methods. Hence, the accurate content of the glycosides is the prerequisite for ensuring the pharmacological efficacy. Aiming at establishing an efficient extraction and determination method for accurate quantitative analysis of calycosin-7-glucoside, liquiritin and glycyrrhizic acid in Huangqi Liuyi Decoction, an on line solid-phase extraction-high-performance liquid chromatography method was developed, using a homemade bio-based monolithic adsorbent. The bio-based adsorbent was prepared in a stainless steel tube, using bio-monomers of methyleugenol and S-allyl-L-cysteine, which effectively reduced the dependence of the polymer field on non-renewable fossil resources and reduced carbon emissions. Furthermore, the prepared adsorbent owned abundant chemical groups, which can produce interactions of hydrogen bond, dipole-dipole, π-π and hydrophobic force with the target glycosides, thus improving the specific recognition ability of the adsorbent. The experiments were carried out on an LC-3000 HPLC instrument with a six-way valve. Methodology validation indicates that the recovery is in the range of 97.0%-103.4% with the RSD in the range of 1.6%-4.0%, due to the specific selectivity of the bio-based monolithic adsorbent for these three glycosides, and good matrix-removal ability for Huangqi Liuyi decoction. The limit of detection is 0.17, 0.50 and 0.33 µg/mL for calycosin-7-glucoside, liquiritin and glycyrrhizic acid, respectively, and the limit of quantitation is 0.50, 1.50 and 1.00 µg/mL, respectively, with the linear range of 2-200 µg/mL for calycosin-7-glucoside, and 5-500 µg/mL for liquiritin and glycyrrhizic acid. The present work provided a simple and efficient method for the extraction and determination of glycosides in complex medicinal plants.

Comparative analysis of dental implant placement accuracy: Semi-active robotic versus free-hand techniques: A randomized controlled clinical trial.

BACKGROUND: Robot-assisted implant surgery has emerged as a novel digital technology, and the accuracy need further assessment. PURPOSE: This study aimed to compare the accuracy of single dental implant placement between a novel semi-active robot-assisted implant surgery (RAIS) method and the conventional free-hand implant surgery (FHIS) method through a multicenter, randomized controlled clinical trial. MATERIALS AND METHODS: Patients requiring single dental implant placement were recruited and randomized into RAIS and FHIS group. Deviations at the platform, apex, and angle between the planned and final implant positions were assessed in both groups. Additionally, the evaluation of instrument and surgical complications was examined. RESULTS: A total of 140 patients (median age: 35.35 ± 12.55 years; 43 males, 97 females) with 140 implants from four different research centers were included, with 70 patients (70 implants) in the RAIS group and 70 patients (70 implants) in the FHIS group. In the RAIS and FHIS groups, the median platform deviations were 0.76 ± 0.36 mm and 1.48 ± 0.93 mm, respectively (p < 0.001); median apex deviations were 0.85 ± 0.48 mm and 2.14 ± 1.25 mm, respectively (p < 0.001); and median angular deviations were 2.05 ± 1.33° and 7.36 ± 4.67°, respectively (p < 0.001). Similar significant difference also presented between RAIS and FHIS group in platform vertical/horizontal deviation, apex vertical/horizontal deviation. Additionally, implants with self-tapping characteristics exhibited significantly larger deviations compared with those without self-tapping characteristics in the RAIS group. Both RAIS and FHIS methods demonstrated comparable morbidity and safety pre- and post-operation. CONCLUSIONS: The results indicated that the RAIS method demonstrated superior accuracy in single dental implant placement compared with the FHIS method. Specifically, RAIS exhibited significantly smaller deviations in platform, apex, and angular positions, as well as platform and apex vertical/horizontal deviations. This clinical trial was not registered prior to participant recruitment and randomization. https://www.chictr.org.cn/showproj.html?proj=195045.

An open tubular capillary electrochromatography column with porous inner surface for protein separation.

An open tubular capillary electrochromatography (OTCEC) column using sole porogen to form porous inner surface has been developed. The porous layer was coated on the capillary inner wall by in situ polymerization in the presence of porogen. The results show that the columns using 1-propanol as sole porogen are appropriate for protein separation. It has higher separation efficiency than the column with the usual coporogen due to much more micropores and mesopores on the porous surface and a higher specific surface area. In addition, the sensitivity of the prepared OTCEC column was improved greatly compared with the dynamically coated capillary with polyvinylpyrrolidone.

A review of recent advances in biomedical applications of smart cellulose-based hydrogels.

In biomedical engineering, smart materials act as media to communicate physiological signals inspired by environmentally responsive stimuli with outer indicators for timely scrutiny and precise therapy. Various physical and chemical processes are applied in the design of specific smart functions. Hydrogels are polymeric networks consisting of hydrophilic chains and chemical groups and they have contributed their unique features in biomedical application as one of the most used smart materials. Numerous raw materials can form hydrogels, in which cellulose and its derivatives have been extensively exploited in biomedicine due to their high hydrophilicity, availability, renewability, biodegradability, biocompatibility, and multifunctional reactivity. This review collates cellulose-based hydrogels and their extensive applications in the biomedical domain, specifically benefiting from the "SMART" concept in their design, synthesis and device assembly. The first section discusses the physical and chemical crosslinking and electrospinning techniques used in the fabrication of smart cellulose-based hydrogels. The second section describes the performance of these hydrogels, and the final section is a comprehensive discussion of their biomedical applications.

Ingestion of a row of artificial dentures in an adult: A case report and review of the literature.

RATIONALE: Foreign body (FB) ingestion is a common clinical emergency, although in most cases, the FB can pass safely through the entire gastrointestinal tract without causing any damage. However, ingestion of large dentures is very rare and alarming, as it can threaten the intestinal mucosa and cause perforation of the gastrointestinal tract, among other complications. PATIENT CONCERNS: A 64-year-old Chinese male was referred to our hospital for removal of a FB, which was a large denture. Clinical symptoms included chest and upper abdominal pain. He had no cough or dyspnea. Medical history included a recent cerebral infarction, craniocerebral surgery, and being bedridden for a long term. DIAGNOSES: We initially suspected a single and smooth denture, complicated by pharyngeal and esophageal mucosal injury. Radiographic examination however showed a 70-mm long opaque object located in the middle and upper esophagus, close to the trachea and aorta. INTERVENTIONS: Multiple dentures and metal hooks were removed via endoscopy using a net, grasping forceps, and rubber jacket. OUTCOMES: The patient recovered well and experienced no postoperative complications. The patient was discharged 5 days after endoscopic therapy. LESSONS: Our case showed that endoscopy was effective for the retrieval of an esophageal FB. For sharp FBs, the use of a net and rubber jacket is a good choice. However, we advocate for appropriate surgery in patients in whom endoscopy is not possible after an accurate diagnosis or those with severe complications.

Development of UPLC-UV-ELSD Method for Fatty Acid Profiling in Polysorbate 80 and Confirmation of the Presence of Conjugated Fatty Acids by Mass Spectrometry, UV Absorbance and Proton Nuclear Magnetic Resonance Spectroscopy.

Polysorbate 80 (PS80), a chemical substance composed of sorbitol, ethylene glycol, and fatty acids, is commonly used in pharmaceutical drug products to stabilize formulations. However, recent studies have demonstrated that PS80 may hydrolyze over time and the released free fatty acids (FFAs) may lead to particle formation. Naming conventions of fatty acids in current pharmacopeia and in products' certificates of analysis (CoA) of PS80 do not typically distinguish between isomeric species of fatty acids in PS80. Thus, methods to fully characterize the fatty acid species present in PS80 raw materials are needed to enhance quality control strategies of pharmaceuticals using PS80. Here, extended effort is taken to characterize fatty acids in hydrolyzed PS80 raw materials and elucidate the identities of isomeric fatty acid species. In this work, a method was developed and optimized for separation and detection of fatty acids in alkaline hydrolyzed PS80 raw materials using ultra performance liquid chromatography (UPLC) with ultra-violet (UV) detection and evaporative light scattering detection (ELSD). Fatty acids not specified in the current pharmacopeias were detected in PS80 raw material by the developed LC-UV-ELSD method including conjugated forms of linoleic and linolenic fatty acid species. Their identities were orthogonally confirmed by retention time agreement with analytical standards, accurate mass by high resolution mass spectrometry, UV absorbance, and proton nuclear magnetic resonance spectroscopy. The detected conjugated fatty acids are theoretically more hydrophobic and less soluble than their unconjugated counterparts and may increase the propensity of PS80 to form particles upon hydrolysis. This work highlights the need for better quality control of PS80 raw material, as it may eventually play a critical role in product quality of therapeutic proteins.

Optimization of Surface-Engineered Micropatterns on Bacterial Cellulose for Guided Scar-Free Skin Wound Healing.

Bacterial cellulose (BC) has been widely used in tissue engineering due to its unique spatial structure and suitable biological properties. In this study, a small biologically active Arginine-Glycine-Aspartic acid-Serine (RGDS) tetrapeptide was incorporated on the porous BC surface followed by a low-energy CO2 laser etching operation. As a result, different micropatterns were established on the BC surface with RGDS only anchored on the raised platform surface of the micropatterned BC (MPBC). Material characterization showed that all micropatterned structures exhibited platforms with a width of ~150 µm and grooves with a width of ~100 µm and a depth of ~300 µm, which displayed distinct hydrophilic and hydrophobic properties. The resulting RGDS-MPBC could hold the material integrity, as well as the microstructure morphology under a humid environment. In-vitro and in-vivo assays on cell migration, collagen deposition, and histological analysis revealed that micropatterns led to significant impacts on wound healing progress compared to the BC without surface-engineered micropatterns. Specifically, the basket-woven micropattern etched on the BC surface exhibited the optimal wound healing outcome with the presence of fewer macrophages and the least scar formation. This study further addresses the potential of adopting surface micropatterning strategies to promote skin wounds towards scar-free outcomes.

Applications of Bacterial Cellulose-Based Composite Materials in Hard Tissue Regenerative Medicine.

BACKGROUND: Cartilage, bone, and teeth, as the three primary hard tissues in the human body, have a significant application value in maintaining physical and mental health. Since the development of bacterial cellulose-based composite materials with excellent biomechanical strength and good biocompatibility, bacterial cellulose-based composites have been widely studied in hard tissue regenerative medicine. This paper provides an overview of the advantages of bacterial cellulose-based for hard tissue regeneration and reviews the recent progress in the preparation and research of bacterial cellulose-based composites in maxillofacial cartilage, dentistry, and bone. METHOD: A systematic review was performed by searching the PubMed and Web of Science databases using selected keywords and Medical Subject Headings search terms. RESULTS: Ideal hard tissue regenerative medicine materials should be biocompatible, biodegradable, non-toxic, easy to use, and not burdensome to the human body; In addition, they should have good plasticity and processability and can be prepared into materials of different shapes; In addition, it should have good biological activity, promoting cell proliferation and regeneration. Bacterial cellulose materials have corresponding advantages and disadvantages due to their inherent properties. However, after being combined with other materials (natural/ synthetic materials) to form composite materials, they basically meet the requirements of hard tissue regenerative medicine materials. We believe that it is worth being widely promoted in clinical applications in the future. CONCLUSION: Bacterial cellulose-based composites hold great promise for clinical applications in hard tissue engineering. However, there are still several challenges that need to be addressed. Further research is needed to incorporate multiple disciplines and advance biological tissue engineering techniques. By enhancing the adhesion of materials to osteoblasts, providing cell stress stimulation through materials, and introducing controlled release systems into matrix materials, the practical application of bacterial cellulose-based composites in clinical settings will become more feasible in the near future.

Effect of Repeated Intravenous Esketamine on Adolescents With Major Depressive Disorder and Suicidal Ideation: A Randomized Active-Placebo-Controlled Trial.

OBJECTIVE: Suicide is a major cause of death in adolescents with limited treatment options. Ketamine and its enantiomers have shown rapid anti-suicidal effects in adults with major depressive disorder (MDD), but their efficacy in adolescents is unknown. We conducted an active, placebo-controlled trial to determine the safety and efficacy of intravenous esketamine in this population. METHOD: A total of 54 adolescents (aged 13-18 years) with MDD and suicidal ideation were included from an inpatient setting and randomly assigned (1:1) to receive 3 infusions of esketamine (0.25 mg/kg) or midazolam (0.02mg/kg) over 5 days, with routine inpatient care and treatment. Changes from baseline to 24 hours after the final infusion (day 6) in the scores of the Columbia Suicide Severity Rating Scale (C-SSRS) Ideation and Intensity (primary outcome) and the Montgomery-Åsberg Depression Rating Scale (MADRS, key secondary outcome) were analyzed using linear mixed models. In addition, the 4-week clinical treatment response was a key secondary outcome. RESULTS: The mean changes in C-SSRS Ideation and Intensity scores from baseline to day 6 were significantly greater in the esketamine group than in the midazolam group (Ideation, -2.6 [SD = 2.0] vs -1.7 [SD = 2.2], p = .007; Intensity, -10.6 [SD = 8.4] vs -5.0 [SD = 7.4], p = .002), and the changes in MADRS scores from baseline to day 6 were significantly greater in the esketamine group than in the midazolam group (-15.3 [SD = 11.2] vs -8.8 [SD = 9.4], p = .004). The rates of anti-suicidal and antidepressant responses at 4 weeks posttreatment were 69.2% and 61.5% after esketamine, and were 52.5% and 52.5% after midazolam, respectively. The most common adverse events in the esketamine group were nausea, dissociation, dry mouth, sedation, headache, and dizziness. CONCLUSION: These preliminary findings indicate that 3-dose intravenous esketamine, added to routine inpatient care and treatment, was an effective and well-tolerated therapy for treating adolescents with MDD and suicidal ideation. CLINICAL TRIAL REGISTRATION INFORMATION: The efficacy and safety of esketamine combined with oral antidepressants in the treatment of major depressive disorder with suicidal ideation. http://www.chictr.org.cn. Chinese Clinical Trial Registry: ChiCTR2000041232. DIVERSITY & INCLUSION STATEMENT: We worked to ensure that the study questionnaires were prepared in an inclusive way. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work. We actively worked to promote sex and gender balance in our author group.

pH and reduction dual-bioresponsive polymersomes for efficient intracellular protein delivery.

pH and reduction dual-bioresponsive nanosized polymersomes based on poly(ethylene glycol)-SS-poly(2-(diethyl amino)ethyl methacrylate) (PEG-SS-PDEA) diblock copolymers were developed for efficient encapsulation and triggered intracellular release of proteins. PEG-SS-PDEA copolymers with PDEA-block molecular weights ranging from 4.7, 6.8, to 9.2 kg/mol were synthesized in a controlled manner via reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-(diethyl amino)ethyl methacrylate (DEAEMA) using PEG-SS-CPADN (CPADN = 4-cyanopentanoic acid dithionaphthalenoate; M(n) PEG = 1.9 kg/mol) as a macro-RAFT agent. These copolymers existed as unimers in water at mildly acidic pH (<7.2) conditions, but readily formed monodisperse nanosized polymersomes (54.5-66.8 nm) when adjusting solution pH to 7.4. These polymersomes were highly sensitive to intracellular pH and reductive environments, which resulted in fast dissociation and aggregation of polymersomes, respectively. Notably, both fluorescein isothiocyanate (FITC)-labeled bovine serum albumin (FITC-BSA) and cytochrome C (FITC-CC) proteins could facilely be encapsulated into polymersomes with excellent protein-loading efficiencies, likely as a result of electrostatic interactions between proteins and PDEA. The in vitro release studies showed that protein release was minimal (<20% in 8 h) at pH 7.4 and 37 °C. The release of proteins was significantly enhanced at pH 6.0 due to collapse of polymersomes. Notably, the fastest protein release was observed under intracellular-mimicking reductive environments (10 mM dithiothreitol, pH 7.4). MTT assays in RAW 264.7 and MCF-7 cells indicated that PEG-SS-PDEA (9.2 k) polymersomes had low cytotoxicity up to a polymer concentration of 300 µg/mL. Confocal laser scanning microscope (CLSM) observations revealed that FITC-CC-loaded PEG-SS-PDEA (9.2 k) polymersomes efficiently delivered and released proteins into MCF-7 cells following 6 h of incubation. Importantly, flow cytometry assays showed that CC-loaded PEG-SS-PDEA (9.2 k) polymersomes induced markedly enhanced apoptosis of MCF-7 cells as compared to free CC and CC-loaded PEG-PDEA (8.9 k) polymersomes (reduction-insensitive control). These dual-bioresponsive polymersomes have appeared to be highly promising for intracellular delivery of protein drugs.

Selective enrichment and determination of polychlorinated biphenyls in milk by solid-phase microextraction using molecularly imprinted phenolic resin fiber coating.

Owing to the severe toxicity and health hazard of polychlorinated biphenyls (PCBs) to humans, the efficient separation and determination of PCBs in dairy products is highly desirable and challenging. In this study, a new solid-phase microextraction (SPME) fiber was prepared by coating of a new molecularly imprinted phenolic resin (MIPR) in situ using a covalent grafting method. The MIPR coating, synthesized from 4-mercaptophenol and glutaraldehyde, provides rough surface with more adsorption sites; furthermore, the coating has a thickness of 1.0 µm, resulting in rapid equilibration. This new device has the advantages such as less coating peeling from the substrate and selective recognition enhancement of the coating. A highly selective and sensitive SPME-based method was developed using the developed fiber, coupled with GC-MS/MS, for the determination of polychlorinated biphenyls (PCBs) in milk samples. The developed MIPR-HS-SPME-GC-MS/MS method showed low detection limits (0.012-0.066 pg mL-1), good linearity (r ≥ 0.9991), satisfactory recovery (77.5-116.7%), efficient enhancement factors (362-2034 folds) and good reusability (50 cycles). Therefore, this is a simple and efficient strategy for monitoring trace PCBs in complex samples and is a potential alternative for improving the selectivity of SPME fibers by introducing MIPR into the fiber coating.

Optimisation of a Mouse Model of Cerebral Ischemia-Reperfusion to Address Issues of Survival and Model Reproducibility and Consistency.

Middle cerebral artery occlusion (MCAO) induced brain ischemia-reperfusion model in Mice is essential for understanding the pathology of stroke and investigating potential treatments, in which a variety of methods may be employed to block the middle cerebral artery (MCA), the most common being through the insertion of a monofilament; however, in vivo ischemia-reperfusion models are associated, particularly in mice, with high variability in lesion volume and high mortality. We aimed to optimise a mouse model of cerebral ischemia-reperfusion, addressing issues of mouse survival, model reproducibility, and consistency. The model was optimised in two ways: first, insert the monofilament directly through the internal carotid artery rather than through the external or common carotid artery, and second, by extending the length of the silicone coating on the monofilament, the length of the silicone coating enables embolization of the beginning of the middle cerebral artery, as well as the anterior cerebral artery and part of the posterior communicating artery. Results: We assessed various parameters, including blood flow changes in the middle cerebral artery, stability of the infarct area, correlation between infarct volume percentages and neurological deficit scores, mortality, weight changes, and wellbeing. We found that optimisation of the surgical procedure may improve mouse wellbeing and reduce mortality, through reduced weight loss and decrease the variability. In conclusion, we suggest that the optimisation of the model is superior for the study of both short and long-term outcomes of ischemic stroke. These results have considerable implications on stroke model selection for researchers.