White light powered antimicrobial nanoagents for triple photothermal, chemodynamic and photodynamic based sterilization.

Antibacterial nanoagents have been increasingly developed due to their favorable biocompatibility, cost-effective raw materials, and alternative chemical or optical properties. Nevertheless, there is still a pressing need for antibacterial nanoagents that exhibit outstanding bacteria-binding capabilities and high antibacterial efficiency. In this study, we constructed a multifunctional cascade bioreactor (GCDCO) as a novel antibacterial agent. This involved incorporating carbon dots (CDs), cobalt sulfide quantum dots (CoSx QDs), and glucose oxidase (GOx) to enhance bacterial inhibition under sunlight irradiation. The GCDCO demonstrated highly efficient antibacterial capabilities attributed to its favorable photothermal properties, photodynamic activity, as well as the synergistic effects of hyperthermia, glucose-augmented chemodynamic action, and additional photodynamic activity. Within this cascade bioreactor, CDs played the role of a photosensitizer for photodynamic therapy (PDT), capable of generating ˙O2- even under solar light irradiation. The CoSx QDs not only functioned as a catalytic component to decompose hydrogen peroxide (H2O2) and generate hydroxyl radicals (˙OH), but they also served as heat generators to enhance the Fenton-like catalysis process. Furthermore, GOx was incorporated into this cascade bioreactor to internally supply H2O2 by consuming glucose for a Fenton-like reaction. As a result, GCDCO could generate a substantial amount of reactive oxygen species (ROS), leading to a significant synergistic effect that greatly induced bacterial death. Furthermore, the in vitro antibacterial experiment revealed that GCDCO displayed notably enhanced antibacterial activity against E. coli (99+ %) when combined with glucose under simulated sunlight, surpassing the efficacy of the individual components. This underscores its remarkable efficiency in combating bacterial growth. Taken together, our GCDCO demonstrates significant potential for use in the routine treatment of skin infections among diabetic patients.

Tumour size predicts risk of recurrence in tall cell subtype papillary thyroid carcinoma.

BACKGROUND: The tall cell subtype of papillary thyroid cancer (TCPTC) is the most common aggressive subtype and often treated aggressively. This approach may not be necessary in smaller tumours without adverse histological characteristics. METHODS: 97 patients with TCPTC defined as a height-to-width ratio of ≥3:1 and at least 30% tall cells were compared against 390 classical papillary thyroid carcinoma (CPTC) based on tumour size with recurrence free survival (RFS) as the primary outcome. RESULTS: TCPTC are more likely to present with adverse histological characteristics. In smaller tumours (<2 â€‹cm), only central lymph node metastasis (HR7.16 p â€‹= â€‹0.03) and multifocality (HR10.11 p â€‹= â€‹0.026) increased recurrence risk. In larger tumours, TCPTC histology (HR3.78 p â€‹= â€‹0.002), lymphovascular invasion (HR3.02 p â€‹= â€‹0.014) and central lymph node metastasis (HR3.24 p â€‹< â€‹0.001) significantly increased recurrence risk. CONCLUSION: TCPTC tumours <2 â€‹cm without central lymph node metastasis and multifocality are similar in risk of recurrence to classical PTC and could be managed with lobectomy.

Mechanoelectronic stimulation of autologous extracellular vesicle biosynthesis implant for gut microbiota modulation.

Pathogenic gut microbiota is responsible for a few debilitating gastrointestinal diseases. While the host immune cells do produce extracellular vesicles to counteract some deleterious effects of the microbiota, the extracellular vesicles are of insufficient doses and at unreliable exposure times. Here we use mechanical stimulation of hydrogel-embedded macrophage in a bioelectronic controller that on demand boost production of up to 20 times of therapeutic extracellular vesicles to ameliorate the microbes' deleterious effects in vivo. Our miniaturized wireless bioelectronic system termed inducible mechanical activation for in-situ and sustainable generating extracellular vesicles (iMASSAGE), leverages on wireless electronics and responsive hydrogel to impose mechanical forces on macrophages to produce extracellular vesicles that rectify gut microbiome dysbiosis and ameliorate colitis. This in vivo controllable extracellular vesicles-produced system holds promise as platform to treat various other diseases.

Cell-derived nanomaterials for biomedical applications.

The ever-growing use of nature-derived materials creates exciting opportunities for novel development in various therapeutic biomedical applications. Living cells, serving as the foundation of nanoarchitectonics, exhibit remarkable capabilities that enable the development of bioinspired and biomimetic systems, which will be explored in this review. To understand the foundation of this development, we first revisited the anatomy of cells to explore the characteristics of the building blocks of life that is relevant. Interestingly, animal cells have amazing capabilities due to the inherent functionalities in each specialized cell type. Notably, the versatility of cell membranes allows red blood cells and neutrophils' membranes to cloak inorganic nanoparticles that would naturally be eliminated by the immune system. This underscores how cell membranes facilitate interactions with the surroundings through recognition, targeting, signalling, exchange, and cargo attachment. The functionality of cell membrane-coated nanoparticles can be tailored and improved by strategically engineering the membrane, selecting from a variety of cell membranes with known distinct inherent properties. On the other hand, plant cells exhibit remarkable capabilities for synthesizing various nanoparticles. They play a role in the synthesis of metal, carbon-based, and polymer nanoparticles, used for applications such as antimicrobials or antioxidants. One of the versatile components in plant cells is found in the photosynthetic system, particularly the thylakoid, and the pigment chlorophyll. While there are challenges in consistently synthesizing these remarkable nanoparticles derived from nature, this exploration begins to unveil the endless possibilities in nanoarchitectonics research.

We have highlighted the Cell-derived Nanomaterials for Biomedical Applications through the lenses of our team who have experiences with working on cell membrane, thylakoids, and studying the impact of nanoparticles on biological phenomenon such as nanomaterialsinduced endothelial leakiness (NanoEL). In this review, we have discussed the progress and the wide potential of nanoarchitectonics in plant systems, animal cells and microorganisms. Due to our unique backgrounds, our take on this topic may be the novelty of the review.

Endothelial leakiness elicited by amyloid protein aggregation.

Alzheimer's disease (AD) is a major cause of dementia debilitating the global ageing population. Current understanding of the AD pathophysiology implicates the aggregation of amyloid beta (Aß) as causative to neurodegeneration, with tauopathies, apolipoprotein E and neuroinflammation considered as other major culprits. Curiously, vascular endothelial barrier dysfunction is strongly associated with Aß deposition and 80-90% AD subjects also experience cerebral amyloid angiopathy. Here we show amyloid protein-induced endothelial leakiness (APEL) in human microvascular endothelial monolayers as well as in mouse cerebral vasculature. Using signaling pathway assays and discrete molecular dynamics, we revealed that the angiopathy first arose from a disruption to vascular endothelial (VE)-cadherin junctions exposed to the nanoparticulates of Aß oligomers and seeds, preceding the earlier implicated proinflammatory and pro-oxidative stressors to endothelial leakiness. These findings were analogous to nanomaterials-induced endothelial leakiness (NanoEL), a major phenomenon in nanomedicine depicting the paracellular transport of anionic inorganic nanoparticles in the vasculature. As APEL also occurred in vitro with the oligomers and seeds of alpha synuclein, this study proposes a paradigm for elucidating the vascular permeation, systemic spread, and cross-seeding of amyloid proteins that underlie the pathogeneses of AD and Parkinson's disease.

Breaking through the basement membrane barrier to improve nanotherapeutic delivery to tumours.

An effective nanotherapeutic transport from the vasculature to the tumour is crucial for cancer treatment with minimal side effects. Here we demonstrate that, in addition to the endothelial barrier, the tumour vascular basement membrane surrounding the endothelium acts as a formidable mechanical barrier that entraps nanoparticles (NPs) in the subendothelial void, forming perivascular NP pools. Breaking through this basement membrane barrier substantially increases NP extravasation. Using inflammation triggered by local hyperthermia, we develop a cooperative immunodriven strategy to overcome the basement membrane barrier that leads to robust tumour killing. Hyperthermia-triggered accumulation and inflammation of platelets attract neutrophils to the NP pools. The subsequent movement of neutrophils through the basement membrane can release the NPs entrapped in the subendothelial void, resulting in increased NP penetration into deeper tumours. We show the necessity of considering the tumour vascular basement membrane barrier when delivering nanotherapeutics. Understanding this barrier will contribute to developing more effective antitumour therapies.

A Detailed Histologic and Molecular Assessment of the Diffuse Sclerosing Variant of Papillary Thyroid Carcinoma.

Diffuse sclerosing variant papillary thyroid carcinoma (DS-PTC) is characterized clinically by a predilection for children and young adults, bulky neck nodes, and pulmonary metastases. Previous studies have suggested infrequent BRAFV600E mutation but common RET gene rearrangements. Using strict criteria, we studied 43 DS-PTCs (1.9% of unselected PTCs in our unit). Seventy-nine percent harbored pathogenic gene rearrangements involving RET, NTRK3, NTRK1, ALK, or BRAF; with the remainder driven by BRAFV600E mutations. All 10 pediatric cases were all gene rearranged (P = .02). Compared with BRAFV600E-mutated tumors, gene rearrangement was characterized by psammoma bodies involving the entire lobe (P = .038), follicular predominant or mixed follicular architecture (P = .003), pulmonary metastases (24% vs none, P = .04), and absent classical, so-called "BRAF-like" atypia (P = .014). There was no correlation between the presence of gene rearrangement and recurrence-free survival. Features associated with persistent/recurrent disease included pediatric population (P = .030), gene-rearranged tumors (P = .020), microscopic extrathyroidal extension (P = .009), metastases at presentation (P = .007), and stage II disease (P = .015). We conclude that DS-PTC represents 1.9% of papillary thyroid carcinomas and that actionable gene rearrangements are extremely common in DS-PTC. DS-PTC can be divided into 2 distinct molecular subtypes and all BRAFV600E-negative tumors (1.5% of papillary thyroid carcinomas) are driven by potentially actionable oncogenic fusions.

Engineering tumoral vascular leakiness with gold nanoparticles.

Delivering cancer therapeutics to tumors necessitates their escape from the surrounding blood vessels. Tumor vasculatures are not always sufficiently leaky. Herein, we engineer therapeutically competent leakage of therapeutics from tumor vasculature with gold nanoparticles capable of inducing endothelial leakiness (NanoEL). These NanoEL gold nanoparticles activated the loss of endothelial adherens junctions without any perceivable toxicity to the endothelial cells. Microscopically, through real time live animal intravital imaging, we show that NanoEL particles induced leakiness in the tumor vessels walls and improved infiltration into the interstitial space within the tumor. In both primary tumor and secondary micrometastases animal models, we show that pretreatment of tumor vasculature with NanoEL particles before therapeutics administration could completely regress the cancer. Engineering tumoral vasculature leakiness represents a new paradigm in our approach towards increasing tumoral accessibility of anti-cancer therapeutics instead of further increasing their anti-cancer lethality.

Minimally invasive adrenalectomy: a cohort study of surgical approach and outcomes.

BACKGROUND: In the context of minimally invasive adrenal surgery, there remains debate about whether the transperitoneal adrenalectomy (TPA) and posterior retroperitoneoscopic adrenalectomy (PRA) approach have equivalent indications. This study aims to examine complication and conversion rates associated with three surgical approaches for adrenal tumours over the last 17 years in a specialized endocrine surgical unit. METHODS: All adrenalectomy cases performed in the period 2005-2021 were identified within a prospectively maintained surgical database. A retrospective cohort study was undertaken with patients divided into two cohorts (2005-2013 and 2014-2021). Surgical approach (open adrenalectomy (OA), TPA, PRA), tumour size, histopathology, complication and conversion rates were compared. RESULTS: During the study period, 596 patients underwent adrenalectomy with 31 and 40 cases each year per cohort. The dominant surgical approach per cohort significantly changed from TPA (79% versus 17%) to PRA (8% versus 69%, P < 0.001), whilst the frequency of OA remained stable (13% versus 15%). TPA removed larger tumours (3.0 ± 2.9 cm) than PRA (2.8 ± 2.2 cm, P = 0.02), with the median size increasing from 3.0 ± 2.5 to 4.5 ± 3.5 cm per cohort (P < 0.001). The maximum tumour sizes treated by TPA and PRA were 15 and 12 cm, respectively. Adrenocortical adenoma was the commonest pathology treated by either laparoscopic technique. Complication rates were greatest for OA (30.1%) with no significant difference between minimally invasive approaches (TPA 7.3%, PRA 8.3%, P = 0.7). Both laparoscopic techniques had equivalent conversion rates (3.6%). PRA was preferably converted to TPA (2.8%) over OA (0.8%). CONCLUSION: This study demonstrates the transition from TPA to PRA, offering similarly low complication and conversion rates.

A Prospective Study of Electromyographic Amplitude Changes During Intraoperative Neural Monitoring for Open Thyroidectomy.

BACKGROUND: Intraoperative nerve monitoring (IONM) of the vagus and recurrent laryngeal nerve (RLN) enables prediction of postoperative nerve function. The underlying mechanism for loss of signal (LOS) in a visually intact nerve is poorly understood. The correlation of intraoperative electromyographic amplitude changes (EMG) with surgical manoeuvres could help identify mechanisms of LOS during conventional thyroidectomy. METHODS: A prospective study of consecutive patients undergoing thyroidectomy was performed with intermittent IONM using the NIM Vital nerve monitoring system. The ipsilateral vagus and RLN was stimulated, and vagus nerve signal amplitude recorded at five time points during thyroidectomy (baseline, after mobilisation of superior pole, medialisation of the thyroid lobe, before release at Ligament of Berry, end of case). RLN signal amplitude was recorded at two time points; after medialisation of the thyroid lobe (R1), and end of case (R2). RESULTS: A total of 100 consecutive patients undergoing thyroidectomy were studied with 126 RLN at risk. The overall rate of LOS was 4.0%. Cases without LOS demonstrated a highly significant vagus nerve median percentage amplitude drop at medialisation of the thyroid lobe (- 17.9 ± 53.1%, P < 0.001), and end of case (- 16.0 ± 47.2%, P < 0.001) compared to baseline. RLN had no significant amplitude drop at R2 compared to R1 (P = 0.207). CONCLUSIONS: A significant reduction in vagus nerve EMG amplitude at medialisation of the thyroid and the end of case compared to baseline indicates that stretch injury or traction forces during thyroid mobilisation are the most likely mechanism of RLN impairment during conventional thyroidectomy.

Diffuse sclerosing variant papillary thyroid carcinoma has worse survival than classic papillary thyroid carcinoma: a meta-analysis.

Diffuse sclerosing variant (DSV) of papillary thyroid carcinomais a rare form of thyroid cancer that demonstrates more aggressive histopathology than classical papillary thyroid carcinoma (c-PTC); however, if this leads to worse survival is debated. Many DSVs are driven by fusion events which are of recent clinical importance due to the advent of targeted RET inhibitors. A systematic search and meta-analysis of the literature was performed to compare outcomes of disease-specific mortality (DSM), metastatic and recurrent disease and the incidence of fusion events between DSV and c-PTC to July 2022. The Newcastle-Ottawa Quality Assessment studies was used to assess quality. An odds ratio (OR) was utilised to measure outcomes with 95% CIs. The Preferred Reporting Items for Systematic Reviews and Meta-analysis guideline was followed. Seventeen studies were included with 874 DSV patients compared to 76,013 c-PTC patients. DSV patients had worse DSM (OR=2.50, 95% CI 1.39-4.51) and presented with a higher rate of metastatic lymph nodes (OR = 5.85, 95% CI 2.73-12.53) and more distant metastases (OR = 3.83, 95% CI 2.17-6.77). DSV patients had higher odds of recurrent disease (OR = 3.23, 95% CI 2.00-5.23) and overall distant metastasis (OR = 2.70, 95% CI 1.74-4.17). Rates of RET fusion alterations for DSV ranged from 25 to 83%. DSV has a worse prognosis than c-PTC with higher rates of recurrent disease and distant metastasis. The high prevalence of RET fusions offers the potential to improve outcomes for patients with DSV.

Attenuating endothelial leakiness with self-assembled DNA nanostructures for pulmonary arterial hypertension.

Vascular endothelium dysfunction plays an important role in oncological and pulmonary diseases. Endothelial barrier dysfunction is the initial step of pulmonary vascular remodeling (PVR) and pulmonary arterial hypertension. Upregulation of a pro-autophagy protein Atg101 in the endothelial cells triggered a cascade of intracellular events that leads to endothelial dysfunction through apoptosis. Herein, we proposed a strategy that used endothelial targeting DNA nanostructures to deliver Atg101 siRNA (siAtg101) as a safe, biocompatible "band-aid" to restore pulmonary arterial endothelial barrier integrity within the intricate milieu of pulmonary cells and the pulmonary vasculature. The siAtg101 and aptamer conjugated DNA nanostructures were found to attenuate hypoxia-induced pulmonary endothelial leakiness with surprisingly high selectivity and efficacy. Further in vivo study revealed that functionalized DNA nanostructures likewise attenuated the vascular remodeling in a monocrotaline-induced PVR mouse model. Mechanistically, functionalized DNA nanostructures suppressed PVR by knocking down Atg101, which in turn, downregulated Beclin-1 and subsequently upregulated VE-cadherin to restore endothelial cells' adherin junctions. This work opened a new window for future nanomaterial design that directly addresses the interfacial endothelial cell layer that often stands between the blood and many diseased sites of nanotherapeutic interest.

The Prognostic Impact of Extent of Vascular Invasion in Follicular Thyroid Carcinoma.

BACKGROUND: Encapsulated angioinvasive follicular thyroid carcinoma (EAFTC) is associated with an increased risk of distant metastasis and reduced survival compared to minimally invasive follicular thyroid carcinoma (MIFTC). There is controversy regarding the extent of surgery and adjuvant radioactive iodine therapy for angioinvasive follicular thyroid carcinoma when stratified by number of foci of angioinvasion. METHODS: All follicular thyroid carcinoma cases from 1990-2018 were identified from a thyroid cancer database. Primary outcomes were distant metastasis-free survival (DMFS) and disease-specific survival (DSS) with factors of interest being age, gender, tumour size, treatment, foci of angioinvasion and histological subtype. RESULTS: A total of 292 cases were identified; 139 MIFTC, 141 EAFTC and 12 widely invasive follicular thyroid carcinoma (WIFTC). Over a follow-up period of 6.25 years, DMFS was significantly reduced (p < 0.001) with 14.2% (EAFTC) and 50% of WIFTC developing metastasis. The risk of metastasis in EAFTC with ≥ 4 foci of angioinvasion was 31.7% (HR = 5.89, p = 0.004), 6.3% for EAFTC with < 4 foci of angioinvasion (HR = 1.74, p = 0.47), compared to 3.6% MIFTC. Age ≥ 50 years (HR = 4.24, p = 0.005) and tumour size (HR = 1.27, p = 0.014) were significantly associated with increased risk of distant metastasis. DSS was reduced significantly (p < 0.001), with 7.8% EAFTC patients dying of disease. For EAFTC patients, DSS was 96.8% for < 4 foci and 82.6% for ≥ 4 foci of angioinvasion (p = 0.003). CONCLUSION: EAFTC is at increased risk of distant metastasis related to the extent of angioinvasion. Tumours with < 4 foci of angioinvasion should be considered for a total thyroidectomy, particularly in older patients.

Chiral nanocrystals grown from MoS2 nanosheets enable photothermally modulated enantioselective release of antimicrobial drugs.

The transfer of the concept of chirality from molecules to synthesized nanomaterials has attracted attention amongst multidisciplinary teams. Here we demonstrate heterogeneous nucleation and anisotropic accumulation of Au nanoparticles on multilayer MoS2 planes to form chiroptically functional nanomaterials. Thiol amino acids with chiral conformations modulate asymmetric growth of gold nanoarchitectures on seeds of highly faceted Au/MoS2 heterostructures. Consequently, dendritic plasmonic nanocrystals with partial chiral morphologies are synthesized. The chirality of dendritic nanocrystals inherited from cysteine molecules refers to the structural characteristics and includes specific recognition of enantiomeric molecules. With integration of the intrinsic photothermal properties and inherited enantioselective characteristics, dendritic Au/MoS2 heterostructures exhibit chirality-dependent release of antimicrobial drugs from hydrogel substrates when activated by exogenous infrared irradiation. A three-in-one strategy involving synthesis of chiral dendritic heterostructures, enantioselective recognition, and controlled drug release system is presented, which improves nanomaterial synthetic technology and enhances our understanding of crucial chirality information.

Development of an Australia and New Zealand Lung Cancer Clinical Quality Registry: a protocol paper.

INTRODUCTION: Lung cancer is the leading cause of cancer mortality, comprising the largest national cancer disease burden in Australia and New Zealand. Regional reports identify substantial evidence-practice gaps, unwarranted variation from best practice, and variation in processes and outcomes of care between treating centres. The Australia and New Zealand Lung Cancer Registry (ANZLCR) will be developed as a Clinical Quality Registry to monitor the safety, quality and effectiveness of lung cancer care in Australia and New Zealand. METHODS AND ANALYSIS: Patient participants will include all adults >18 years of age with a new diagnosis of non-small-cell lung cancer (NSCLC), SCLC, thymoma or mesothelioma. The ANZLCR will register confirmed diagnoses using opt-out consent. Data will address key patient, disease, management processes and outcomes reported as clinical quality indicators. Electronic data collection facilitated by local data collectors and local, state and federal data linkage will enhance completeness and accuracy. Data will be stored and maintained in a secure web-based data platform overseen by registry management. Central governance with binational representation from consumers, patients and carers, governance, administration, health department, health policy bodies, university research and healthcare workers will provide project oversight. ETHICS AND DISSEMINATION: The ANZLCR has received national ethics approval under the National Mutual Acceptance scheme. Data will be routinely reported to participating sites describing performance against measures of agreed best practice and nationally to stakeholders including federal, state and territory departments of health. Local, regional and (bi)national benchmarks, augmented with online dashboard indicator reporting will enable local targeting of quality improvement efforts.

Anionic nanoplastic exposure induces endothelial leakiness.

The global-scale production of plastics has been instrumental in advancing modern society, while the rising accumulation of plastics in landfills, oceans, and anything in between has become a major stressor on environmental sustainability, climate, and, potentially, human health. While mechanical and chemical forces of man and nature can eventually break down or recycle plastics, our understanding of the biological fingerprints of plastics, especially of nanoplastics, remains poor. Here we report on a phenomenon associated with the nanoplastic forms of anionic polystyrene and poly(methyl methacrylate), where their introduction disrupted the vascular endothelial cadherin junctions in a dose-dependent manner, as revealed by confocal fluorescence microscopy, signaling pathways, molecular dynamics simulations, as well as ex vivo and in vivo assays with animal model systems. Collectively, our results implicated nanoplastics-induced vasculature permeability as primarily biophysical-biochemical in nature, uncorrelated with cytotoxic events such as reactive oxygen species production, autophagy, and apoptosis. This uncovered route of paracellular transport has opened up vast avenues for investigating the behaviour and biological effects of nanoplastics, which may offer crucial insights for guiding innovations towards a sustainable plastics industry and environmental remediation.

Inducible endothelial leakiness in nanotherapeutic applications.

All intravenous delivered nanomedicine needs to escape from the blood vessel to exert their therapeutic efficacy at their designated site of action. Failure to do so increases the possibility of detrimental side effects and negates their therapeutic intent. Many powerful anticancer nanomedicine strategies rely solely on the tumor derived enhanced permeability and retention (EPR) effect for the only mode of escaping from the tumor vasculature. However, not all tumors have the EPR effect nor can the EPR effect be induced or controlled for its location and timeliness. In recent years, there have been exciting developments along the lines of inducing endothelial leakiness at the tumor to decrease the dependence of EPR. Physical disruption of the endothelial-endothelial cell junctions with coordinated biological intrinsic pathways have been proposed that includes various modalities like ultrasound, radiotherapy, heat and even nanoparticles, appear to show good progress towards the goal of inducing endothelial leakiness. This review explains the intricate and complex biological background behind the endothelial cells with linkages on how updated reported nanomedicine strategies managed to induce endothelial leakiness. This review will also end off with fresh insights on where the future of inducible endothelial leakiness holds.

Defect-Rich Molybdenum Sulfide Quantum Dots for Amplified Photoluminescence and Photonics-Driven Reactive Oxygen Species Generation.

Transition metal dichalcogenide (TMD) quantum dots (QDs) with defects have attracted interesting chemistry due to the contribution of vacancies to their unique optical, physical, catalytic, and electrical properties. Engineering defined defects into molybdenum sulfide (MoS2 ) QDs is challenging. Herein, by applying a mild biomineralization-assisted bottom-up strategy, blue photoluminescent MoS2 QDs (B-QDs) with a high density of defects are fabricated. The two-stage synthesis begins with a bottom-up synthesis of original MoS2 QDs (O-QDs) through chemical reactions of Mo and sulfide ions, followed by alkaline etching that creates high sulfur-vacancy defects to eventually form B-QDs. Alkaline etching significantly increases the photoluminescence (PL) and photo-oxidation. An increase in defect density is shown to bring about increased active sites and decreased bandgap energy; which is further validated with density functional theory calculations. There is strengthened binding affinity between QDs and O2 due to lower gap energy (∆EST ) between S1 and T1 , accompanied with improved intersystem crossing (ISC) efficiency. Lowered gap energy contributes to assist e- -h+ pair formation and the strengthened binding affinity between QDs and 3 O2 . Defect engineering unravels another dimension of material properties control and can bring fresh new applications to otherwise well characterized TMD nanomaterials.

Brain Accumulation and Toxicity Profiles of Silica Nanoparticles: The Influence of Size and Exposure Route.

Nanoparticles (NPs) can make their way to the brain and cause in situ damage, which is a concern for nanomaterial application and airborne particulate matter exposure. Our recent study indicated that respiratory exposure to silica nanoparticles (SiO2 NPs) caused unexpected cardiovascular toxic effects. However, the toxicities of SiO2 NPs in other organs have warranted further investigation. To confirm the accumulation of SiO2 NPs in the brain, we introduced SiO2 NPs with different diameters into mice via intranasal instillation (INI) and intravenous injection (IVI) in parallel. We found that SiO2 NPs may target the brain through both olfactory and systemic routes, but the size of SiO2 NPs and delivery routes both significantly affected their brain accumulation. Surprisingly, while equivalent SiO2 NPs were found in the brain regions, brain lesions were distinctly much higher in INI than in the IVI group. Mechanistically, we showed that SiO2 NPs introduced via INI induced brain apoptosis and autophagy, while the SiO2 NPs introduced via IVI only induced autophagy in the brain.

Sulfur Defect-Engineered Biodegradable Cobalt Sulfide Quantum Dot-Driven Photothermal and Chemodynamic Anticancer Therapy.

Chemodynamic therapy (CDT), as a powerful tumor therapeutic approach with low side effects and selective therapeutic efficiency, has gained much attention. However, the low intracellular content of H2O2 and the cellular bottleneck of low intracellular oxidative reaction rates at tumor sites have limited the antitumor efficacy of CDT. Herein, a series of sulfur-deficient engineered biodegradable cobalt sulfide quantum dots (CoSx QDs) were constructed for improved synergistic photothermal- and hyperthermal-enhanced CDT of tumors through regulating the photothermal conversion efficiency (PCE) and Fenton-like activity. Through defect engineering, we modulated the PCE and promoted the Fenton catalytic capability of CoSx QDs. With increasing defect sites, the Fenton-like activity improved to generate more toxic •OH, while the photothermal effect declined slightly. In light of above unique superiorities, the best synergistic effects of CoSx QDs were obtained through comparing their PCE and catalytic activity by regulating the sulfur defect fraction degree in these QDs during the synthetic process. In addition, the ultrasmall size and biodegradation endowed QDs with the ability to be rapidly decomposed to ions that were easily excreted after therapy, thus reducing biogenic accumulation in the body with lowered systemic side effects. The in vitro/vivo results demonstrated that the photothermal- and hyperthermal-enhanced chemodynamic effect of CoSx QDs can enable remarkable anticancer properties with favorable biocompatibility. In this study, the defect-driven mechanism for the photothermal-enhanced Fenton-like reaction provides a flexible strategy to deal with different treatment environments, holding great promise in developing a multifunctional platform for cancer treatment in the future.