Synthesis and Characterization of Guanidinylated CO-Releasing Micelles Based on Biodegradable Polycarbonate.

As one of the gaseous signals in living cells, carbon monoxide (CO) not only participates in many biological activities but also serves as a therapeutic agent for the treatment of diseases. However, the limited applicability of CO in gas therapy emerges from the inconvenience of direct administration of CO. Here we reported the construction of guanidinylated CO-releasing micelles, which are composed of poly(trimethylene carbonate) (PTMC)-based CO donors. The in vitro studies demonstrated that micelles in the presence of light irradiation can induce cancer death, whereas no obvious toxicity to normal cells was observed. Moreover, the functionalization of guanidine groups imparts improved cellular uptake efficiency to micelles owing to the specific interactions with the surface of cells, which synergistically increase the anticancer capacity of the system. The guanidine-functionalized CO-releasing micelles provide a new strategy for the construction of CO-releasing nanocarriers, which are expected to find applications in gas therapeutics.

Giant Cell Tumor of Bone: Effect of Longer Dosing Intervals of Denosumab on Tumor Control and Bone-related Complications.

BACKGROUND: Denosumab is an effective treatment for giant cell tumor of the bone (GCTB) but can cause clinically significant adverse effects. Current approved dosing is every 4 weeks after 3 weekly loading doses. We assessed whether alternative, longer dosing intervals are associated with differences in efficacy or bone toxicity. METHODS: Single institution retrospective chart review was conducted on patients with GCTB over 18 years old who received at least 1 year of standard denosumab dosing. Patients identified using a free-text search engine with keywords "giant cell tumor" and "denosumab" from January 1998 to August 2020. RESULTS: Approximately 37 patients with GCTB (19F, 18M) were identified with median age of 37 years (range 22-73). Dosing interval was increased in 38% (n = 14), with the most common final dosing interval 12 weeks (n = 8). Six patients (16%) had bone complications: osteonecrosis of the jaw (n =5), atypical fracture (n = 1), and nonhealing dental wounds (n = 2). All patients with bone complications were on the monthly dosing schedule, but there was no statistically significant difference compared to longer dosing intervals (P = .22). No statistically significant difference in median PFS was noted (P = .97). However, 5-year PFS was superior in patients treated with less frequent versus standard dosing of denosumab (P = .036). CONCLUSIONS: Increasing the interval of denosumab dosing for GCTB provided similar tumor control compared to standard dosing and lower absolute number of bone toxicity events. Larger studies are needed to better define the optimal interval of denosumab administration and the effect on efficacy, toxicity, and associated healthcare expense.

Lignin synthesized by CmCAD2 and CmCAD3 in oriental melon (Cucumis melo L.) seedlings contributes to drought tolerance.

KEY MESSAGE: CmCAD2 and CmCAD3 function more positively than CmCAD1 in oriental melon for lignin synthesis which is important to ensure internal water status and thus for drought tolerance. Well-lignification may be the guarantee of efficient axial water transport and barrier of lateral water flow in oriental melon tolerating drought stress, however remains to be verified. As an important enzyme in monolignol synthesis pathway, five cinnamyl alcohol dehydrogenase (CAD) genes were generally induced in melon seedlings by drought. Here we further revealed the roles of CmCAD1, 2, and 3 in lignin synthesis and for drought tolerance. Results found that overexpressing CmCAD2 or 3 strongly recovered CAD activities, lignin synthesis and composition in Arabidopsis cadc cadd, whose lignin synthesis is disrupted, while CmCAD1 functioned modestly. In melon seedlings, silenced CmCAD2 and 3 individually or collectively decreased CAD activities and lignin depositions drastically, resulting in dwarfed phenotypes. Reduced lignin, mainly composed by guaiacyl units catalyzed by CmCAD3, is mainly due to the limited lignification in tracheary elements and development of Casparion strip. While CmCAD1 and 2 exhibited catalysis to p-coumaraldehyde and sinapaldehyde, respectively. Compared with CmCAD1, drought treatments revealed higher sensitivity of CmCAD2 and/or 3 silenced melon seedlings, accompanying with lower relative water contents, water potentials and relatively higher total soluble sugar contents. Slightly up-regulated expressions of aquaporin genes together with limited lignification might imply higher lateral water loss in stems of silenced lines. In Arabidopsis, CmCAD2 and 3 transgenic lines enhanced cadc cadd drought tolerance through recovering lignin synthesis and root development, accompanying with decreased electrolyte leakage ratios and increased RWCs, thus improved survival rates. Briefly, lignin synthesized by CmCAD2 and 3 functions importantly for drought tolerance in melon.

Ultra-pH-Responsive and Tumor-Penetrating Nanoplatform for Targeted siRNA Delivery with Robust Anti-Cancer Efficacy.

RNA interference (RNAi) gene silencing technologies have shown significant potential for treating various diseases, including cancer. However, clinical success in cancer therapy remains elusive, mainly owing to suboptimal in vivo delivery of RNAi therapeutics such as small interference RNA (siRNA) to tumors. Herein, we developed a library of polymers that respond to a narrow pH change (ultra-pH-responsive), and demonstrated the utility of these materials in targeted and deep tumor-penetrating nanoparticle (NP) for in vivo RNAi. The new NP platform is mainly composed of the following key components: i) internalizing RGD (iRGD) to enhance tumor targeting and tissue penetration; ii) polyethylene glycol (PEG) chains to prolong blood circulation; and iii) sharp pH-responsive hydrophobic polymer to improve endosome escape. Through systematic studies of structure-function relationship, the optimized RNAi NPs (<70 nm) showed efficient gene silencing and significant inhibition of tumor growth with negligible toxicities in vivo.

Polymeric Nanoparticles Amenable to Simultaneous Installation of Exterior Targeting and Interior Therapeutic Proteins.

Effective delivery of therapeutic proteins is a formidable challenge. Herein, using a unique polymer family with a wide-ranging set of cationic and hydrophobic features, we developed a novel nanoparticle (NP) platform capable of installing protein ligands on the particle surface and simultaneously carrying therapeutic proteins inside by a self-assembly procedure. The loaded therapeutic proteins (e.g., insulin) within the NPs exhibited sustained and tunable release, while the surface-coated protein ligands (e.g., transferrin) were demonstrated to alter the NP cellular behaviors. In vivo results revealed that the transferrin-coated NPs can effectively be transported across the intestinal epithelium for oral insulin delivery, leading to a notable hypoglycemic response.

Hydrophobic Cysteine Poly(disulfide)-based Redox-Hypersensitive Nanoparticle Platform for Cancer Theranostics.

Selective tumor targeting and drug delivery are critical for cancer treatment. Stimulus-sensitive nanoparticle (NP) systems have been designed to specifically respond to significant abnormalities in the tumor microenvironment, which could dramatically improve therapeutic performance in terms of enhanced efficiency, targetability, and reduced side-effects. We report the development of a novel L-cysteine-based poly (disulfide amide) (Cys-PDSA) family for fabricating redox-triggered NPs, with high hydrophobic drug loading capacity (up to 25 wt% docetaxel) and tunable properties. The polymers are synthesized through one-step rapid polycondensation of two nontoxic building blocks: L-cystine ester and versatile fatty diacids, which make the polymer redox responsive and give it a tunable polymer structure, respectively. Alterations to the diacid structure could rationally tune the physicochemical properties of the polymers and the corresponding NPs, leading to the control of NP size, hydrophobicity, degradation rate, redox response, and secondary self-assembly after NP reductive dissociation. In vitro and in vivo results demonstrate these NPs' excellent biocompatibility, high selectivity of redox-triggered drug release, and significant anticancer performance. This system provides a promising strategy for advanced anticancer theranostic applications.

Development of multinuclear polymeric nanoparticles as robust protein nanocarriers.

One limitation of current biodegradable polymeric nanoparticles is their inability to effectively encapsulate and sustainably release proteins while maintaining protein bioactivity. Here we report the engineering of PLGA-polycation nanoparticles with a core-shell structure that act as a robust vector for the encapsulation and delivery of proteins and peptides. The optimized nanoparticles can load high amounts of proteins (>20 % of nanoparticles by weight) in aqueous solution without organic solvents through electrostatic interactions by simple mixing, thereby forming nanospheres in seconds with diameters <200 nm. The relationship between nanosphere size, surface charge, PLGA-polycation composition, and protein loading is also investigated. The stable nanosphere complexes contain multiple PLGA-polycation nanoparticles, surrounded by large amounts of protein. This study highlights a novel strategy for the delivery of proteins and other relevant molecules.

Nitric Oxide-Releasing Tubular Polymersomes toward Advanced Gas Therapeutic Carriers.

Nitric oxide (NO) not only plays a vital role in a series of physiological processes but also has great potential for therapeutic applications. One of the existing challenges in using NO as a gas therapeutic is the inconvenience of gaseous NO storage, and thus, it is of importance to develop NO-releasing vehicle platforms. Although a variety of polymer-based NO-releasing nanoparticles have been constructed, a majority of the systems are limited to spherical morphologies. Here we present the preparation of biodegradable NO-releasing amphiphilic block copolymers containing poly(ethylene glycol) (PEG) and poly(trimethylene carbonate-4-nitro-3-(trifluoromethyl)) (PTMC-NF), which can self-assemble into tubular polymersomes. The tubular polymersomes with high aspect ratio structures showed much faster NO-releasing behavior, in contrast to their spherical counterparts under light irradiation. We found that the amount of NO released from tubular polymersomes is 1.5 times that from spherical polymersomes. More importantly, the tubular polymersomes have an enhanced anticancer performance compared to spherical polymersomes, demonstrating that the morphology of the NO-releasing polymersomes has a significant effect on their anticancer ability. In view of the benefits of NO-releasing tubular polymersomes, we expect that they can be used as an efficient NO delivery system for enhanced gas therapy.

Adsorption abilities and mechanisms of Lactobacillus on various nanoplastics.

As a new type of pollutants, nanoplastics (NPs), which are easily ingested by humans from food wraps, salt, drinking water, have been widely detected in various water environments, and are a threat to human health. It is therefore urgent to develop an efficient method to remove NPs from the diet or relief its harm. In the present study, the possibility of a well-known human probiotic, lactic acid bacteria (LAB), was evaluated to remove NPs from food as an absorbent. The results indicated that LAB from infant feces could efficiently absorb three types NPs, i.e. polypropylene (PP), polyethylene (PE), and polyvinyl chloride (PVC) with the adsorption rates of PP > PE > PVC (PP 78.57%, PE 71.59%, PVC 66.57%) and the Nile red-stained NPs being aggregated on the surfaces of Lactobacillus cells. The smaller the particle size, the stronger the ability of NP adsorption on the cell surface. The hydrophobicity of NPs and bacterial cells affected the adsorption process. The measurement of adsorption rates of different cell components indicated that the overall adsorption effect of cell was better than that of individual cell component. The results of molecular dynamics analysis revealed that adsorption was mainly caused by electrostatic interactions, van der Waals forces, and hydrogen bonds. The hydrophobic interaction was also involved in adsorption process. Overall, this research may provide new information for developing new strategies for NPs removal in intestinal environment.

Saliva microbiome alterations in dental fluorosis population.

Background: We aimed to explore saliva microbiome alterations in dental fluorosis population. Methods: The prevalence of dental fluorosis was examined in 957 college students. Dean's fluorosis index was used to evaluate the dental fluorosis status. Changes in the composition of the salivary microbiome were assessed in a subset of these patients (100 healthy controls, 100 dental fluorosis patients). Results: Dental fluorosis affected 47% of the student sample, and incidence was unrelated to gender. Compared with healthy controls, the microbiota of patients with dental fluorosis exhibited increased diversity, with increased abundance of Treponema lecithinolyticum, Vibrio metschnikovii, Cupriavidus pauculus, Pseudomonas, Pseudomonadaceae, Pseudomonadales, and decreased abundance of Streptococcus mutans, Streptococcus sanguinis, Gemella, and Staphylococcales. Function analyses showed increases in arginine biosynthesis in patients affected by dental fluorosis, together with reductions in amino sugar and nucleotide sugar metabolism, fructose and mannose metabolism, and starch and sucrose metabolism. Conclusions: These results suggest that there are striking differences in salivary microbiome between healthy controls and dental fluorosis patients. Dental fluorosis may contribute to periodontitis and systemic lung diseases. There is a need for cohort studies to determine whether altering the salivary microbiota in dental fluorosis patients can alter the development of oral or systemic diseases.

Determination of N-acetyl-DL-leucine in the saliva of healthy volunteers and diabetic patients using ultra-performance liquid chromatography with fluorescence detection.

BACKGROUND: Recent studies have indicated that N-acetyl-leucine (N-Ac-Leu) is a potential biomarker of diabetes. This study aimed to measure the levels of enantiomers of the chiral molecule N-Ac-DL-Leu in the saliva of patients with type 2 diabetes and further determine the potential association between them. METHOD: A novel validated method was established using ultra-performance liquid chromatography (UPLC) with fluorescence (FL) detection, in which precolumn derivatization of (R)-(-)-4-(N, N-dimethylaminosulfonyl)-7-(3-aminopyrrolidin-l-yl)-2,1,3-benzoxadiazole [(R)-(-)-DBD-APy] was used for the simultaneous determination and chiral separation of N-Ac-DL-Leu in human saliva. RESULTS: The labeled N-Ac-DL-Leu diastereomers were completely separated, with a resolution value of 1.93. Additionally, excellent linearity for N-Ac-DL-Leu was observed, with high coefficients of correlation (r2 ≥ 0.9999) in the range of 10-300 µM; the limit of quantitation (signal-to-noise ratio = 10) was 40-120 pmol/mL, and the mean recoveries of N-Ac-L-Leu and N-Ac-D-Leu were 102.48% and 104.68%, respectively. The levels of N-Ac-Leu in the saliva of diabetic patients and healthy volunteers were determined, and it was found that the levels of N-Ac-DL-Leu in the saliva of diabetic patients were significantly lower than those in healthy volunteers. (p < 0.01). CONCLUSIONS: The proposed method was successfully applied for the measurement of N-Ac-DL-Leu enantiomers in the saliva of diabetic patients and healthy volunteers.

Cobalt loaded electrospun poly(ε-caprolactone) grafts promote antibacterial activity and vascular regeneration in a diabetic rat model.

Diabetes has been associated with postoperative complications, such as increased risk of tissue infection and impaired tissue repair caused by destabilization of hypoxia-inducible factor-1α (HIF-1α). Consequently, it is imperative to fabricate anti-bacterial and pro-regenerative small-diameter vascular grafts for treating cardiovascular disease in diabetic patients. Herein, we developed electrospun cobalt ion (Co2+)-loaded poly (ε-caprolactone) (PCL) microfiber vascular grafts (PCL-Co grafts). The released Co2+ significantly increased the stabilization of HIF-1α in high-glucose (HG)-treated HUVECs (HG-HUVECs) and macrophages (HG-macrophages). This resulted in enhanced cell migration, nitric oxide production, and secretion of bioactive factors by HG-HUVECs, and polarization of HG-macrophages toward M2 phenotypes in vitro. The Co2+ also conferred anti-bacterial properties to the grafts, while not perturbing the inherent anti-bacterial activities of HG-macrophages. Following abdominal artery implantation into type 2 diabetes mellitus (T2DM) rats, PCL-Co grafts were evaluated for performance in infection (grafts pre-contaminated with Staphylococcus aureus) and prophylaxes models (grafts alone). PCL-Co grafts prevented the incidence of subsequent infection in prophylaxes model and effectively inhibited the bacterial growth in the infection model. PCL-Co grafts also significantly enhanced cellularization, vascularization, endothelialization, contractile SMC regeneration and macrophages polarization in both models. Collectively, PCL-Co grafts exhibited the potential to combat infection and improve tissue regeneration under diabetes conditions.

[Symptom-based relationship between gastroesophageal reflux disease and laryngopharyngeal reflux disease].

OBJECTIVE: To explore the relationship between gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux disease (LPRD) based on symptoms. METHODS: A total of 1090 patients undergoing upper digestive tract motility test were invited to complete the surveys of reflux disease questionnaire and reflux symptom index from August 2007 to October 2010. And 895 responders provided valid answers. There were 474 females and 421 males. RESULTS: Among 895 responders, 351 patients had neither, 218 suffered both conditions, 237 were diagnosed as GERD alone and 89 LPRD alone. No difference was found in age (P = 0.383)or gender ratio (P = 0.227). In 455 GERD patients, there were 218 LPRD cases (47.9%). In 307 LPRD patients, 218 (71.0%) had concurrent GERD. In GERD patients, the frequency and degree of feeling of stomach content reflux into mouth were correlated with RSI (r = 0.115, 0.141, P = 0.007, 0.001). CONCLUSION: GERD and LPRD may coexist or occur alone. Because of a high concurrent ratio of LPRD in GERD, the treatment strategy of GERD should be modified accordingly. In GERD patients, the feeling of stomach content reflux into mouth may suggest a possibility of LPRD.

Analysis of the distribution of supernumerary teeth and the characteristics of mesiodens in Bengbu, China: a retrospective study.

OBJECTIVES: To evaluate the distribution of supernumerary teeth (ST) and the characteristics of mesiodens. METHODS: Panoramic radiographs of 48,700 outpatients were used to assess the distribution of ST. A total of 142 cone beam computed tomography (CBCT) images were used to evaluate the characteristics of mesiodens. RESULTS: A total of 1.24% of individuals aged from 1 to 98 years were diagnosed with ST among 48,700 outpatients, and males had a higher percentage of ST than females (2.94:1); patients aged 6-12 years were the most frequently diagnosed. More females had ST impacted in bone than males. The percentages of patients with 1 and 2 ST were 0.949 and 0.290%, respectively. The most frequent location, crown direction, and morphology of mesiodens were palatal, inverted, and conical, respectively. The tooth lengths of mesiodens in males and of erupted mesiodens were longer than that those in females and of unerupted mesiodens, respectively. Inverted mesiodens had the shortest tooth length compared with vertical and horizontal mesiodens. These results were statistically significant. CONCLUSIONS: The distribution of ST and mesiodens were both related to gender, and patients aged 6-12 years were the most frequently detected. The length of the mesiodens was associated with the growth direction and mesiodens eruption.

A convenient sampling and noninvasive dried spot method of uric acid in human saliva: Comparison of serum uric acid value and salivary uric acid in healthy volunteers and hyperuricemia patients.

Concentration of uric acid (UA) in serum is one of the markers used to diagnose gout and hyperuricemia. However, serum treatment and storage are cumbersome, and wounds are susceptible to infection. Therefore, a new sampling and analysis method using noninvasive biological samples has been developed, called the dried spot method of UA in human saliva (DSM-UHS). Saliva (5 µL) was dropped on filter paper (a spot with a diameter of 5 mm) containing hypoxanthine (IS) (5 µL) and dried at room temperature for 30 min. The filter paper was immersed in 200 µL of lithium carbonate solution and shaken in a block bath shaker for 5 min at 30 °C. Afterward, the extraction was concentrated and reconstituted with 100 µL of lithium carbonate solution analyzed by HPLC-UV. When comparing the concentration of UA in the human saliva of hyperuricemia patients (HPs) and with that of healthy volunteers (HVs), we observed the concentration of UA was higher in the HPs than in the HVs (p < 0.0001). In addition, the results showed a significant linear relationship between the content of UA in saliva and the content of UA in the serum (r = 0.6243). The content of UA in human saliva could indirectly reflect the content of UA in human serum. Then DSM-UHS could be used to determine the content of UA in the saliva of HVs and HPs. This study provides a new research method and strategy for the determination of human UA content and the clinical prewiring of hyperuricemia.

Platelet-activating factor levels of serum and gingival crevicular fluid in nonsmoking patients with periodontitis and/or coronary heart disease.

The purpose of the present study was to investigate systemic and local levels of platelet-activating factor (PAF), a potent proinflammatory mediator implicated in cardiovascular pathophysiology in adult nonsmoking patients with periodontitis with or without coronary heart disease (CHD). Eighty-seven volunteers, 25 periodontitis patients, 19 periodontitis with CHD patients, 19 CHD patients, and 24 healthy controls were included, and periodontal conditions were assessed. Gingival crevicular fluid (GCF) and venous blood were collected, and PAF levels were measured by enzyme-linked immunosorbent assay. PAF levels in serum (303.3 ± 204 pg/ml) and in GCF (26.3 ± 6 pg/µl) of the periodontitis group with CHD, the periodontitis group (serum, 302.4 ± 241 pg/ml and GCF, 26.3 ± 8 pg/µl) and the CHD group (serum, 284.7 ± 192 pg/ml and GCF, 20.8 ± 6 pg/µl) were significantly higher than the healthy control group (serum, 65.4 ± 35 pg/ml and GCF, 7.7 ± 3 pg/µl; p < 0.05). In summary, the present study could demonstrate that in patients with periodontitis, the inflammatory mediator PAF is released into serum at least in the same range as for patients with coronary heart disease. However, no additive effects were seen when both conditions were present.

Surface silanization and grafting reaction of nano-silver loaded zirconium phosphate and properties strengthen in 3D-printable dental base composites.

In this work, surface modification of nano silver-loaded zirconium phosphate (6S-NP3) were obtained from simultaneous silanization of γ-methacryloxypropyltrimethoxysilane (MPS) and grafting reaction of methyl methacrylate (MMA), and then mixed with denture base resin (E-Denture) to prepare denture base composites using 3D printer printing. FT-IR spectra confirmed that surface silanization and grafting reaction had occurred and MPS and MMA were successfully anchored on the surface of 6S-NP3. XRD results demonstrated that surface modification had occurred on the surface of hexagonal lattice. The average diameter data indicated that the surface modification decreased the average diameter of nanoparticles. The water contact angle (WCA) was found increasing as the surface modification. SEM images illustrated that the dispersion and compatibility of nanoparticles in denture base composite materials had improved. The results of mechanical properties presented that composites with the addition of P-6S-NP3 nanoparticles achieved higher flexural strength, flexural modulus and impact strength. The data of antibacterial activities revealed that composites had exhibited good antibacterial activities against either S. aureus or E. coli and the latter showed better antibacterial efficacy than the former.

Preparation and characterization of tissue-factor-loaded alginate: Toward a bioactive hemostatic material.

Tissue factor (TF), an integral membrane protein, is by far the most potent known triggering agent of blood coagulation. Inspired by TF's effectiveness in initiating coagulation, this work aims to develop hemostatic materials with TF-integrated liposomes, which combined with alginate biopolymers are designed as composite pastes or hydrogels cross-linked with Ca2+. Fluorescence measurements revealed that the proteoliposomes were evenly distributed within alginate matrices, which also remained intact after release into simulated body fluid. The proteoliposome release rate from the composite pastes increased with the decrease of alginate concentration from 3% to 1%, or relative to the corresponding hydrogels. The latter also showed a swelling property. The combination with alginate enhanced TF procoagulant activity, and most importantly the resultant composites exhibited superior hemostatic performance, yielding a shortest blood clotting time of 1.5 min while untreated blood took 14.2 min to clot, with no cytotoxicity against mammalian cells.

Polyethylenimine: An Intranasal Adjuvant for Liposomal Peptide-Based Subunit Vaccine against Group A Streptococcus.

Group A Streptococcus (GAS) and GAS-related infections are a worldwide challenge, with no commercial GAS vaccine available. Polyethylenimine (PEI) attaches to the cells' surface and delivers cargo into endosomal and cytosolic compartments. We hypothesized that this will confer mucosal adjuvant properties for peptide antigens against group A Streptococcus (GAS). In this study, we successfully demonstrated the development of PEI incorporated liposomes for the delivery of a lipopeptide-based vaccine (LCP-1) against GAS. Outbred mice were administrated with the vaccine formulations intranasally, and immunological investigation showed that the PEI liposomes elicited significant mucosal and systemic immunity with the production of IgA and IgG antibodies. Antibodies were shown to effectively opsonize multiple isolates of clinically isolated GAS. This proof-of-concept study showed the capability for PEI liposomes to act as a safe vehicle for the delivery of GAS peptide antigens to elicit immune responses against GAS infection, making PEI a promising addition to liposomal mucosal vaccines.