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Integrating hyperthermia with conventional cancer therapies shows promise in improving treatment efficacy while mitigating their side effects. Nanotechnology-based hyperthermia, particularly using superparamagnetic iron oxide nanoparticles (SPIONs), offers a simplified solution for cancer treatment. In this study, we developed composites of SPION quantum dots (Fe3O4) with reduced graphene oxide (Fe3O4/RGO) using the coprecipitation method and investigated their potential application in magnetic hyperthermia. The size of Fe3O4 nanoparticles was controlled within the quantum dot range (≤10 nm) by varying the synthesis parameters, including reaction time as well as the concentration of ammonia and graphene oxide, where their biocompatibility was further improved with the inclusion of polyethylene glycol (PEG). These nanocomposites exhibited low cytotoxic effects on healthy cells (CHO-K1) over an incubation period of 24 h, though the inclusion of PEG enhanced their biocompatibility for longer incubation periods over 48 h. The Fe3O4/RGO composites dispersed in acidic pH buffer (pH 4.66) exhibited considerable heating effects, with the solution temperature increasing by ~10 °C within 5 min of exposure to pulsed magnetic fields, as compared to their dispersions in phosphate buffer and aqueous dimethylsulfoxide solutions. These results demonstrated the feasibility of using quantum dot Fe3O4/RGO composites for magnetic hyperthermia-based therapy to treat cancer, with further studies required to systematically optimize their magnetic properties and evaluate their efficacy for in vitro and in vivo applications. [ABSTRACT FROM AUTHOR]

This review comprehensively summarizes potential applications of SiO2–polymer composites especially in oil industries: enhanced oil recovery (EOR), loss circulation (LC), and relative permeability modification (RPM). The significance of these materials has been widely recognized as high-performance functional materials as they combine the flexural properties of the polymer and enhanced thermo-mechanical characteristics of SiO2 nanoparticles (NPs). The composite exhibits increased impact resistance and tensile strength without decreasing the flexibility of the polymer. The addition of SiO2 into the polymer matrices can further extend the possibility of creating hierarchically structured materials, and therefore, SiO2–polymer composites have attracted great interest in various industries. Compared to other materials, suspended NPs/polymer composites offer various advantages, such as high thermal stability, long-term stability, salinity tolerance, and viscosity increment which are very crucial criteria for increased oil production. [ABSTRACT FROM AUTHOR]

Dendritic mesoporous organosilica nanoparticles (DMON) are a new class of biodegradable nanoparticles suitable for biomolecule delivery. We studied the photochemical internalization (PCI) and photodynamic therapy (PDT) of DMON to investigate new ways for DMON to escape from the endosomes-lysosomes and deliver biomolecules into the cytoplasm of cells. We added photosensitizers in the framework of DMON and found that DMON were loaded with siRNA or FVIII factor protein. We made four formulations with four different photosensitizers. The photosensitizers allowed us to perform imaging of DMON in cancer cells, but the presence of the tetrasulfide bond in the framework of DMON quenched the formation of singlet oxygen. Fortunately, one formulation allowed us to efficiently deliver proapoptotic siRNA in MCF-7 cancer cells leading to 31% of cancer cell death, without irradiation. As for FVIII protein, it was loaded in two formulations with drug-loading capacities (DLC) up to 25%. In conclusion, DMON are versatile nanoparticles capable of loading siRNA and delivering it into cancer cells, and also loading FVIII protein with good DLC. Due to the presence of tetrasulfide, it was not possible to perform PDT or PCI. [ABSTRACT FROM AUTHOR]

The delivery of large cargos of diameter above 15 nm for biomedical applications has proved challenging since it requires biocompatible, stably-loaded, and biodegradable nanomaterials. In this study, we describe the design of biodegradable silica-iron oxide hybrid nanovectors with large mesopores for large protein delivery in cancer cells. The mesopores of the nanomaterials spanned from 20 to 60 nm in diameter and post-functionalization allowed the electrostatic immobilization of large proteins (e.g. mTFP-Ferritin, ~ 534 kDa). Half of the content of the nanovectors was based with iron oxide nanophases which allowed the rapid biodegradation of the carrier in fetal bovine serum and a magnetic responsiveness. The nanovectors released large protein cargos in aqueous solution under acidic pH or magnetic stimuli. The delivery of large proteins was then autonomously achieved in cancer cells via the silica-iron oxide nanovectors, which is thus a promising for biomedical applications. [ABSTRACT FROM AUTHOR]

Despite the worldwide interest generated by periodic mesoporous organosilica (PMO) bulk materials, the design of PMO nanomaterials with controlled morphology remains largely unexplored and their properties unknown. In this work, we describe the first study of PMO nanoparticles (NPs) based on meta-phenylene bridges, and we conducted a comparative structure-property relationship investigation with para-phenylene-bridged PMO NPs. Our findings indicate that the change of the isomer drastically affects the structure, morphology, size, porosity and thermal stability of PMO materials. We observed a much higher porosity and thermal stability of the para-based PMO which was likely due to a higher molecular periodicity. Additionally, the para isomer could generate multipodal NPs at very low stirring speed and upon this discovery we designed a phenylene-ethylene bridged PMO with a controlled Janus morphology. Unprecedentedly high payloads could be obtained from 40 to 110 wt % regardless of the organic bridge of PMOs. Finally, we demonstrate for the first time the co-delivery of two cargos by PMO NPs. Importantly, the cargo stability in PMOs did not require the capping of the pores, unlike pure silica, and the delivery could be autonomously triggered in cancer cells by acidic pH with nearly 70 % cell killing. [ABSTRACT FROM AUTHOR]

BACKGROUND: In April 2014, a surge in cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection was seen in Jeddah, Saudi Arabia. The aim of this study is to describe the demographic and clinical features, laboratory and radiological findings of MERS-CoV patients identified during this outbreak in a single tertiary hospital. METHODS: All laboratory-confirmed MERS-CoV cases who presented to King Faisal Specialist Hospital from March 1, 2014, to May 30, 2014, were identified. Patients' charts were reviewed for demographic information, comorbidities, clinical presentations, and outcomes. RESULTS: A total of 39 patients with confirmed MERS-CoV infection were identified. Twenty-one were male (54%), aged 40 ± 19 years and included 3 (8%) pediatric patients (<18-year-old). 16 (41%) patients were health care workers. Twenty-one (53%) patients were previously healthy whereas eighteen (47%) had at least one comorbidity. The predominant comorbidities included hypertension (31%), diabetes (26%), respiratory (23%), and renal disease (18%). Thirty patients (81%) were symptomatic at presentation, fever (69%) being the most common complaint. The overall mortality rate was 28%. In univariate analysis, older age, hypertension, and chronic kidney disease were associated with mortality. CONCLUSIONS: MERS-CoV presentation varies from asymptomatic infection to severe respiratory disease causing death. Future studies to identify the risk factors for worse outcome are needed. [ABSTRACT FROM AUTHOR]

We describe biodegradable mesoporous hybrid nanoparticles (NPs) in the presence of proteins and their applications for drug delivery. We synthesized oxamide phenylene-based mesoporous organosilica nanoparticles (MON) in the absence of a silica source which had remarkably high organic content and high surface areas. Oxamide functions provided biodegradability in the presence of trypsin model proteins. MON displayed exceptionally high payloads of hydrophilic and hydrophobic drugs (up to 84 wt %), and a unique zero premature leakage without the pore capping, unlike mesoporous silica. MON were biocompatible and internalized into cancer cells for drug delivery. [ABSTRACT FROM AUTHOR]

Graphene oxide-wrapped gold nanorods (GO@AuNRs) offer efficient drug delivery as well as NIR laser photothermal therapy (PTT) in vitro and in vivo. However, no real-time observation of drug release has been reported to better understand the synergy of chemotherapy and PTT. Herein, surface-enhance Raman spectroscopy (SERS) is employed to guide chemo-photothermal cancer therapy by a two-step mechanism. In the presence of GO as an internal standard, SERS signals of DOX (doxorubicin) loaded onto GO@AuNRs are found to be pH-responsive. Both DOX and GO show strong SERS signals before the DOX@GO@AuNRs are endocytic. However, when the DOX@GO@AuNRs enter acidic microenvironments such as endosomes and/or lysosomes, the DOX signals start decreasing while the GO signals remain the same. This plasmonic antenna could be used to identify the appropriate time to apply the PTT laser during chemo-photothermal therapy. [ABSTRACT FROM AUTHOR]

Nanotechnology Biodegradable hybrid materials that combine high porosity and drug payload without drug leakage are in high demand. In their Communication on page 14806 ff., N. M. Khashab and et al. report the first completely biodegradable mesoporous hybrid nanovectors in the presence of proteases. Oxamide‐phenylene‐based mesoporous organosilica nanoparticles were synthesized with oxamide functions to enable the biodegradability in the presence of trypsin. Exceptionally high payloads of drugs (up to 84 wt%) and a unique zero premature leakage without the pore capping were observed. [ABSTRACT FROM AUTHOR]