Diet changes due to urbanization in South Africa are linked to microbiome and metabolome signatures of Westernization and colorectal cancer

Transition from traditional high-fiber to Western diets in urbanizing communities of Sub-Saharan Africa is associated with increased risk of non-communicable diseases (NCD), exemplified by colorectal cancer (CRC) risk. To investigate how urbanization gives rise to microbial patterns that may be amenable by dietary intervention, we analyzed diet intake, fecal 16 S bacteriome, virome, and metabolome in a cross-sectional study in healthy rural and urban Xhosa people (South Africa). Urban Xhosa individuals had higher intakes of energy (urban: 3,578 ± 455; rural: 2,185 ± 179 kcal/d), fat and animal protein. This was associated with lower fecal bacteriome diversity and a shift from genera favoring degradation of complex carbohydrates (e.g., Prevotella) to taxa previously shown to be associated with bile acid metabolism and CRC. Urban Xhosa individuals had higher fecal levels of deoxycholic acid, shown to be associated with higher CRC risk, but similar short-chain fatty acid concentrations compared with rural individuals. Fecal virome composition was associated with distinct gut bacterial communities across urbanization, characterized by different dominant host bacteria (urban: Bacteriodota; rural: unassigned taxa) and variable correlation with fecal metabolites and dietary nutrients. Food and skin microbiota samples showed compositional differences along the urbanization gradient. Rural-urban dietary transition in South Africa is linked to major changes in the gut microbiome and metabolome. Further studies are needed to prove cause and identify whether restoration of specific components of the traditional diet will arrest the accelerating rise in NCDs in Sub-Saharan Africa.

A 700 nm LED Light Activated Ru(II) Complex Destroys Tumor Cytoskeleton via Photosensitization and Photocatalysis

Photoactivable chemotherapy (PACT) using metallic complexes provides spatiotemporal selectivity over drug activation for targeted anticancer therapy. However, the poor absorption in near-infrared (NIR) light region of most metallic complexes renders tissue penetration challenging. Herein, an NIR light triggered dinuclear photoactivable Ru(II) complex (Ru2) is presented and the antitumor mechanism is comprehensively investigated. The introduction of a donor-acceptor-donor (D-A-D) linker greatly enhances the intramolecular charge transition, resulting in a high molar extinction coefficient in the NIR region with an extended triplet excited state lifetime. Most importantly, when activated by 700 nm NIR light, Ru2 exhibits unique slow photodissociation kinetics that facilitates synergistic photosensitization and photocatalytic activity to destroy diverse intracellular biomolecules. In vitro and in vivo experiments show that when activated by 700 nm NIR light, Ru2 exhibits nanomolar photocytotoxicity toward 4T1 cancer cells via the induction of calcium overload and endoplasmic reticulum (ER) stress. These findings provide a robust foundation for the development of NIR-activated Ru(II) PACT complexes for phototherapeutic application.

Exploring Hollow Mesoporous Silica Nanoparticles as a Nanocarrier in the Delivery of Foot-And-Mouth Disease Virus-like Particle Vaccines

Virus-like particle (VLP) vaccine is considered to be the most promising candidate alternative to the traditional inactivated vaccine for foot-and-mouth disease (FMD). To elicit a desired immune response, hollow mesoporous silica nanoparticles (HMSNs) have been synthesized and utilized as a nanocarrier for FMD VLP vaccine delivery. The as-prepared HMSNs displayed a relatively small particle size (∼260 nm), large cavity (∼150 nm), and thin wall (∼55 nm). The inherent structural superiorities make them ideal nanocarriers for the FMD VLP vaccine, which exhibited good biocompatibility, great protein-loading capacity, high antibody-response level, and protective efficiency, even comparable to commercial adjuvant ISA 206. All the results suggested that HMSNs may be a valid nanocarrier in VLP-based vaccines.

Nano-carrier DMSN for effective multi-antigen vaccination against SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has had a profound impact on the global health and economy. While mass vaccination for herd immunity is effective, emerging SARS-CoV-2 variants can evade spike protein-based COVID-19 vaccines. In this study, we develop a new immunization strategy by utilizing a nanocarrier, dendritic mesoporous silica nanoparticle (DMSN), to deliver the receptor-binding domain (RBD) and conserved T-cell epitope peptides (DMSN-P-R), aiming to activate both humoral and cellular immune responses in the host. The synthesized DMSN had good uniformity and dispersion and showed a strong ability to load the RBD and peptide antigens, enhancing their uptake by antigen-presenting cells (APCs) and promoting antigen delivery to lymph nodes. The DMSN-P-R vaccine elicited potent humoral immunity, characterized by highly specific RBD antibodies. Neutralization tests demonstrated significant antibody-mediated neutralizing activity against live SARS-CoV-2. Crucially, the DMSN-P-R vaccine also induced robust T-cell responses that were specifically stimulated by the RBD and conserved T-cell epitope peptides of SARS-CoV-2. The DMSN demonstrated excellent biocompatibility and biosafety in vitro and in vivo, along with degradability. Our study introduces a promising vaccine strategy that utilizes nanocarriers to deliver a range of antigens, effectively enhancing both humoral and cellular immune responses to prevent virus transmission.

A novel Gd3+ DTPA-bisamide complex with high relaxivity as an MRI contrast agent

A novel Gd(III) complex-based magnetic resonance imaging (MRI) contrast agent GdL has been designed and synthesized, which exhibited a much higher relaxivity (7.8 mM^-1 s^-1) than the commercially used Magnevist® (3.5 mM^-1 s^-1), good water solubility (>100 mg mL^-1), excellent thermodynamic stability (log KGdL = 17.21 ± 0.27), high biosafety and biocompatibility. In particular, the relaxivity of GdL increased to 26.7 mM^-1 s^-1 in a 4.5% bovine serum albumin (BSA) solution at 1.5 T, which was not significant in other commercial MRI contrast agents. The interaction sites and interaction types of GdL and BSA were further demonstrated by molecular docking simulations. Furthermore, the in vivo MRI behaviour was evaluated by using a 4T1 tumour-bearing mouse model. These results suggested that GdL is an excellent T₁-weighted MRI contrast agent and has the potential to be applied in clinical diagnosis.

Bio-mineralization of virus-like particles by metal-organic framework nanoparticles enhances the thermostability and immune responses of the vaccines

Virus-like particle (VLPs) vaccines have been extensively studied due to their good immunogenicity and safety; however, they highly rely on cold-chain storage and transportation. Nanotechnology of bio-mineralization as a useful strategy has been employed to improve the thermal stability and immunogenicity of VLPs. A zeolitic imidazole framework (ZIF-8), a core-shell structured nanocomposite, was applied to encapsulate foot-and-mouth disease virus (FMDV) VLPs. It was found that the ZIF-8 shell enhanced the heat resistance of VLPs and promoted their ability to be taken up by cells and escape from lysosomes. The VLPs-ZIF-8 easily activated antigen-presenting cells (APCs), triggered higher secretion levels of cytokines, and elicited stronger immune responses than VLPs alone even after being treated at 37 °C for 7 days. This platform has good potential in the development of VLP-based vaccine products without transportation.

Evaluation of the Effect of Inactivated Transmissible Gastroenteritis Virus Vaccine with Nano Silicon on the Phenotype and Function of Porcine Dendritic Cells

A transmissible gastroenteritis virus (TGEV) is a porcine enteropathogenic coronavirus, causing acute swine enteric disease especially in suckling piglets. Mesoporous silica nanoparticles (MSNs) are safe vaccine adjuvant, which could enhance immune responses. Our previous research confirmed that nano silicon had immune-enhancing effects with inactivated TGEV vaccine. In this study, we further clarified the immune-enhancing mechanism of the inactivated TGEV vaccine with MSNs on porcine dendritic cells (DCs). Our results indicated that the inactivated TGEV vaccine with MSNs strongly enhanced the activation of the DCs. Expressions of TLR3, TLR5, TLR7, TLR9, and TLR10, cytokines IFN-α, IL-1β, IL-6, IL-12, and TNF-α, cytokine receptor CCR-7 of immature DCs were characterized and showed themselves to be significantly higher in the inactivated TGEV vaccine with the MSN group. In summary, the inactivated TGEV vaccine with MSNs has effects on the phenotype and function of porcine DCs, which helps to better understand the immune-enhancing mechanism.

Four Simple Biomimetic Mineralization Methods to Improve the Thermostability and Immunogenicity of Virus-like Particles as a Vaccine against Foot-and-Mouth Disease

The need for a cold chain system during storage and transport substantially increases the cost of vaccines. Virus-like particles (VLPs) are among the best countermeasures against foot and mouth disease virus (FMDV). However, VLPs are composed of pure proteins, and thus, are susceptible to heat. To address this problem, four simple biomimetic mineralization methods with the use of calcium phosphate were developed to improve heat tolerance via biomineralization. The results showed that biomineralization can significantly improve the heat resistance of VLPs. The biomineralized VLPs can be stored at low as 25 °C for eight days, and 37 °C for four days. Animal experiments showed that biomineralization had no effect on the immunogenicity of VLPs or the expression of specific antibodies (Abs) and neutralizing Abs. Even after heat treatment at 37 °C for four days, the biomineralized VLPs remained immunogenic and produced highly specific and neutralizing Abs with a high rate of protection. These results suggest that these biomineralization approaches can promote the thermal stability of VLPs against and significantly reduce dependence on cold storage and delivery systems.

Fluorescence distinguishing of SO2 derivatives and Cys/GSH from multi-channel signal patterns and visual sensing based on smartphone in living cells and environment

Sulfur dioxide (SO₂), cysteine (Cys) and glutathione (GSH), which perform crucial actions in regulating the balance of human, are closely related reactive sulfur species (RSS). Moreover, SO₂ is one of the most concerned air pollutants, which is easily soluble in water and forms its derivatives. Therefore, it is highly desirable to differentiate SO₂ derivatives and Cys/GSH in living cells and environment. Herein, a new near-infrared (NIR) mitochondria-targeted fluorescent probe, NIR-CG, which could distinguish SO₂ derivatives and Cys/GSH by using multiple sets of signal patterns under single excitation was reported. NIR-CG exhibited different fluorescence signal modes to SO₃^2- and Cys/GSH with low limit of detection (17.1 nM for SO₃^2-, 17.3 nM for Cys and 25.9 nM for GSH). The recognition mechanisms of NIR-CG to SO₃^2- and Cys/GSH were verified by HRMS, ¹H NMR and DFT calculation. NIR-CG had good ability of mitochondrial targeted and fluorescence imaging in cells. What's more, NIR-CG showed great recovery rates (101-104%) in the determination of SO₃^2- in actual water samples. It was worth noting that NIR-CG-based paper strip successfully realized the visual quantitative detection of SO₃^2- and Cys/GSH by use of smartphone, which offered a novel method to develop powerful sensing platform.

Construction of an Effective Delivery System for DNA Vaccines Using Biodegradable Polylactic Acid Based Microspheres

Nanotechnology represents a new impetus for biomedical research applications, especially using nanotechnology to formulate microspheres or nanospheres based delivery system for treatment of infectious diseases in animals. In this work, polylactic acid (PLA) microspheres with an average size of 156 nm were prepared by combining emulsion polymerization coupled with emulsion-solvent evaporation. Coating with polyethylenimine (PEI) polymers increased the surface charges of the resulting PLA/PEI microspheres, thus enabled plasmid DNA to adsorb tightly to the microspheres. As expected, the plasmid DNA was successfully transferred into the pig kidney-15 cells with high transfection efficiency. In addition, the protection rate of PLA/PEI microspheres loaded with DNA vaccine against foot-and-mouth disease in guinea pigs reached 87.5%, which was significantly higher than that of the pure DNA vaccine group. These results indicated that PLA/PEI microspheres were expected to be an effective delivery system for DNA vaccines.

An ultrasensitive and visible lighting-up probe for imaging thiophenols in water samples, in serum and visualizing thiophenols-induced oxidative stress process in live cells

Thiophenols, a class of significant industrial materials, are extremely toxic in environmental as well live cells. However, the process of live cells responding to thiophenols is not well understood. Herein, an innovative "OFF-ON" probe FY for thiophenols selectively in 100% aqueous solution was reported. It featured rapid response (~150 s), prominent sensitivity (detection limit: 5 nM), and large Stokes shift (~104 nm), which assured specific detection of thiophenols in A375 cells, HeLa cells and environment. Especially, it proved that thiophenols in live cells can be eliminated by endogenous reactive oxygen species (ROS), indicating that thiophenols may result in cellular oxidative stress. As well, it was resoundingly put into recognizing of thiophenols quantitatively in actual water samples and in serum.

A smart nanoprobe based on a gadolinium complex encapsulated by ZIF-8 with enhanced room temperature phosphorescence for synchronous oxygen sensing and photodynamic therapy

The phosphorescence lifetime approach based on the room temperature phosphorescence (RTP) property has received considerable attention in recent years due to its excellent performance in the precise measurement of oxygen. Herein, a smart nanoprobe, Gd[PC]@ZIF-8, was designed and assembled by homogenously encapsulating a rare-earth complex phosphor Gd[(Pyr)₄cyclen] (Pyr = pyrenol) into a zeolitic imidazolate framework (ZIF-8). Because of the restriction of the metal-organic framework (MOF) matrix and host-guest interactions, the nanoprobe Gd[PC]@ZIF-8 exhibited highly enhanced RTP properties, including intensity, quantum yield, and elongated decay lifetime. It displayed an outstanding linear relationship between the phosphorescence decay lifetime, intensity and oxygen concentration, which can be applied in the field of oxygen sensing. Moreover, the complex Gd[(Pyr)₄cyclen] in the nanoprobe Gd[PC]@ZIF-8 served as a favorable photosensitizer that resulted in the simultaneous conversion of sufficient oxygen molecules into single state oxygen (¹O₂) under irradiation during the phosphorescence quenching process, which is conducive to photodynamic therapy (PDT). Thus, the design of the smart nanoprobe Gd[PC]@ZIF-8 in this study provides an ingenious strategy of utilizing a MOF as a matrix to enhance the RTP properties of phosphors for synchronous oxygen sensing and PDT.

Highly specific monitoring and imaging of endogenous and exogenous cysteine in living cells

Cys is one of the important biothiols and its abnormal concentration may pose a threat to human health. Therefore, the monitoring of Cys in organisms is of great significance. GSH and Hcy, as the other two biothiols, have similar chemical structures and active sites to Cys. Consequently, developing fluorescent probes to independently detect Cys has become a challenging problem. Keeping this in mind, α-β unsaturated ketone as a recognition group was integrated into the coumarin group skeleton to synthesize a fluorescent probe SC. After the nucleophilic addition reaction of Cys with SC, the conjugated system of SC was blocked and the fluorescent enhanced obviously. SC was able to detect Cys specifically under the same excitation with a low detection limit (11.1 nM). SC showed a rapid respond to Cys (120 s) and good fluorescent stability over a wide pH range. In addition, it achieved extracorporeal circulation in the presence of H₂O₂ or NEM. In the end, SC could be applied to detecting endogenous and exogenous Cys under biological condition due to its slight cytotoxicity and good biocompatibility. This provided a powerful tool for studying the physiological function of Cys exclusively.

A novel drug–drug nanohybrid for the self-delivery of porphyrin and cis-platinum

The thriving development of nanotechnology has greatly promoted the development of drug delivery systems (DDSs) in the past decades. However, most DDSs themselves cannot serve as diagnostic reagents and must be metabolized, by which they may become poisonous and even cause immune reactions. In this study, a novel self-delivery drug–drug system (SDDS) nanohybrid based on the coordination assembly of a photodynamic reagent, tetra-(4-carboxyphenyl)porphyrin (TCPP), and a chemotherapy reagent, cis-platinum, was designed and synthesized. The four carboxyl groups of TCPP can compete with the chloride ions of cis-platinum by coordination interactions, forming a TCPP-cis-platinum nanohybrid (PCNH) for the purpose of photodynamic/chemotherapeutic synergistic treatment with a combinational index of 0.28. Meanwhile, the PCNH system can effectively protect the photosensitizer TCPP from photobleaching when irradiated continuously in the photodynamic therapy (PDT) process, which is very crucial for PDT. Furthermore, introduction of the heavy atom platinum can greatly enhance the producing efficiency of ¹O₂ by 46%. In addition, the red emission fluorescence of TCPP is beneficial for monitoring and tracing the process of drug delivery when used in vitro. This work may pave a new way for the design of new integrated nanohybrids for diagnosis and synergistic treatment.

A novel self-delivery drug–drug system nanohybrid constructed by the coordination assembly of porphyrin and cis-platinum was used for synergetic photodynamic therapy and chemotherapy.

Uniform dendrimer-like mesoporous silica nanoparticles as a nano-adjuvant for foot-and-mouth disease virus-like particle vaccine

Dendrimer-like mesoporous silica nanoparticles (MSNs) with large center-radial mesopores have been prepared for macromolecular protein loading and delivery.

A multifunctional two-photon fluorescent probe for detecting H2S in wastewater and GSH in vivo

A novel turn-on fluorescent probe, which coumarin-fused coumarin was used as fluorophore to link with 2, 4- dinitrodiphenyl ether moiety that has high selectivity and sensitivity for H₂S and thiols, was designed and synthesized. Our probe YB can sensitively react with H₂S and GSH to release free fluorophore with strong fluorescence signals. The probe YB could use as a significant molecular imaging tool to study the endogenous GSH in living cell and a practical detector for H₂S in the papermaking wastewater.

Augmentative compression plating versus exchanging reamed nailing for nonunion of femoral shaft fracture after intramedullary nailing : A retrospective cohort study

Aim of the present study was to compare the outcomes between exchanging reamed nailing (ERN) and augmentative compression plating (ACP) in treatment of femoral shaft nonunion after intra-medullary nailing (IMN) retrospectively. A retrospective, multicentre study was performed with 188 patients (190 cases)with femoral shaft nonunion after IMN, who received therapy with either ERN (n = 92) for 44/92 (47.8%) cases of nonisthmal nonunions and 48/92 (52.2%) cases of isthmal nonunions or ACP (n = 98) for 48/98 (49%) cases of nonisthmal nonunions and 50/98 (51%) cases of isthmal nonunions. Operation time, intraoperative blood loss, time to union, union rate, postoperative draining volume and complication rate were compared between ERN and ACP group. After a mean follow-up of 4.6 years (range 1-8.1 years), the bone union occurred in 98/98 (100%) cases in -total ACP group versus 80/92 (87%) cases in total ERN group [odds ratio (OR) = 3.34, 95% confidence interval (CI) 0.8-1.6]. Twelve cases with re-nonunion in the total ERN group included 10/12 (83.3%) cases of nonisthmal nonunions and 2/12 (16.7%) cases of isthmal nonunion with cortical bone defect > 3 cm. The average time to union, the intraoperative blood loss and the complication rate in total ERN group were also both significantly more than that in total ACP group (p = 0.031, p = 0.042, p = 0.028). No -significant difference was found in the average operation time between the two total groups (p = 0.213). However, for nonisthmal nonunions, the mean operation time for ERN group was 126.8 ± 19.6 min in -comparison to ACP group (88.6 ± 15.2 min), significant difference was found between ERN group and ACP group (p = 0.021). ACP could obtain the higher bone union rate and shorter time to union than ERN in the treatment of femoral shaft nonunion after failed IMN. Especially for nonisthmal femoral shaft nonunions or isthmal.

A reversible rhodamine 6G-based fluorescence turn-on probe for Fe3+ in water and its application in living cell imaging

A reversible fluorescent probe L based on rhodamine 6G was synthesized for the optical detection of Fe³⁺ in water.

Exploitation and application of a highly sensitive Ru(II) complex-based phosphorescent chemodosimeter for Hg2+ in aqueous solutions and living cells

A novel Ru(II) complex-based phosphorescent probe Rubpy-1 was designed and synthesized conveniently by incorporating of chemodosimeter into the luminophor, which exhibits good water solubility, longer excitation wavelength, and rapid turn-on phosphorescent response only toward Hg(2+) in aqueous system under physiological pH. The spectral response mechanism and Hg(2+)-promoted structure change of the chemodosimeter were analyzed in detail by theoretical calculations and electrospray ionization mass spectrometry. When time-resolved photoluminescence techniques were used, the Rubpy-1 could eliminate effectively the signal interference from the short-lived background fluorescence in complicated media, accompanied by the significant improvement of the signal-to-noise ratio and the accuracy of the detection. Furthermore, Rubpy-1 showed low cytotoxicity and excellent membrane permeability toward living cells, which was successfully applied to monitor intracellular Hg(2+) effectively by confocal luminescence imaging.

Design and application of a water-soluble phosphorescent Ru(ii) complex as turn-on sensing material for Hg2+

A turn-on Ru(ii)-based phosphorescent chemodosimeter for Hg²⁺ is designed by introducing Hg²⁺-promoted desulfurization and intramolecular cyclic guanylation of thiourea reaction into the luminophor.

Selective removal of organochlorine pesticides (OCPs) from aqueous solution by triolein-embedded composite adsorbent

A novel composite adsorbent (CA-T) was used for the selective removal of organochlorine pesticides (OCPs) from aqueous solution. The adsorbent was composed of the supporting activated carbon and the surrounding triolein-embedded cellulose acetate membrane. Scanning electron microscopy (SEM), N2 adsorption isotherms and fluorescence methods were used to characterize the physicochemical properties of CA-T. Triolein was perfectly embedded in the cellulose acetate membrane and deposited on the surface of activated carbon. The adsorbent was stable in water and no triolein leakage was detected during the test periods. Some organochlorine pesticides (OCPs), such as dieldrin, endrin, aldrin, and heptachlor epoxide, were used as model contaminants and removed by CA-T in laboratory batch experiments. The adsorption isotherm followed the Freundlich equation and the kinetic data fitted well to the pseudo-second-order reaction model. Results also indicated that CA-T appeared to be a promising adsorbent with good selectivity and satisfactory removal rate for lipophilic OCPs from aqueous solutions when present in trace amounts. The adsorption rate and removal efficiency for lipophilic OCPs were positively related to their octanol-water partition coefficients (log K(ow)). Lower residual concentrations of OCPs were achieved when compared to granular activated carbon (GAC).