Thallium is a non essential and highly toxic metal listed by USEPA and the European Water Framework Directive as a priority pollutant. It is present in the environment mainly as Tl(I) and Tl(III) ...usually at very low concentrations, which makes it a challenging element requiring high sensitive instrumental techniques to measure it in complex matrices. The average concentration of thallium in the Earth's crust is generally below 1 ppm and its geochemical behaviour and mobility is often compared to that of potassium. In non-contaminated freshwater, the thallium concentration is generally below 1 μg/L and rarely exceeds 20 ng/L in the open ocean. The affinity of thallium for iron and manganese oxyhydroxides is often observed in soil and sediment where its concentrations normally remain in the low ppm except for mine and contaminated areas. Thallium is present at low ng/m3 in aerosols and air particulates but can increase to higher levels in highly urbanized areas and in mining and industrialized zones. For this review, more than 285 papers containing information of thallium in natural waters, soils, sediments and air particulates have been consulted but only a low number of them present information on the speciation of the metal.
•A review of Tl levels is water, soil, sediment and air particulates is presented.•Concentrations of Tl are generally below 1 μg/L in non-contaminated freshwater.•Concentrations of Tl rarely exceed 20 ng/L in the open ocean.•Non-contaminated soils and sediments are generally below or at the low ppm level.•More studies are needed on the chemical speciation of Tl in environmental samples.
Lockdown is an effective nonpharmaceutical intervention to reduce coronavirus disease 2019 (COVID-19) transmission, but it restricts daily activity. We aimed to investigate the impact of lockdown on ...pediatric body weight and body mass index (BMI).
The systematic review and meta-analysis were conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. Four online databases (EMBASE, Medline, the Cochrane Library and CINAHL) were searched.
The pooled results showed that lockdown was associated with significant body weight gain (MD 2.67, 95% CI 2.12-3.23;
< 0.00001). The BMI of children with comorbidities or obesity did not change significantly. The BMI of general population was significantly higher during lockdown than before the pandemic (MD 0.94, 95% CI 0.32-1.56;
= 0.003). However, heterogeneity was high (I
= 84%). Among changes in weight classification, increases in the rates of obesity (OR 1.23, 95% CI 1.10-1.37;
= 0.0002) and overweight (OR 1.17, 95% CI 1.06-1.29;
= 0.001) were reported.
Our meta-analysis showed significant increases in body weight and BMI during lockdown among school-age children and adolescents. The prevalence of obesity and overweight also increased. The COVID-19 pandemic worsened the burden of childhood obesity.
Graphene and its derivatives have unique physical and chemical properties that make them promising vehicles for photothermal therapy (PTT)-based cancer treatment. With intrinsic near-infrared (NIR) ...absorption properties, graphene-based nanomaterials can be used for PTT and other therapeutics, particularly in combination therapy, to provide successful thermal ablation of cancer cells. In the recent years, advances in graphene-based PTT have produced efficient and efficacious tumor inhibition via nanomaterial structural design and different functionalizations of graphene-derived nanocomposites. Graphene-based nanosystems exhibit multifunctional properties that are useful for PTT applications including enhancement of multimodalities, guided imaging, enhanced chemotherapy and low-power efficient PTT for optimum therapeutic efficiency. Therefore, in this review, we address critical issues and future aspects of PTT-based combination therapy.
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Triple-negative breast cancer (TNBC) is an aggressive subtype lacking estrogen receptors, progesterone receptors and lacks HER2 overexpression. This absence of critical molecular targets poses ...significant challenges for conventional therapies. Immunotherapy, remarkably immune checkpoint blockade, offers promise for TNBC treatment, but its efficacy remains limited. Epigenetic dysregulation, including altered DNA methylation, histone modifications, and imbalances in regulators such as BET proteins, plays a crucial role in TNBC development and resistance to treatment. Hypermethylation of tumor suppressor gene promoters and the imbalance of histone methyltransferases such as EZH2 and histone deacetylases (HDACs) profoundly influence tumor cell proliferation, survival, and metastasis. In addition, epigenetic alterations critically shape the tumor microenvironment (TME), including immune cell composition, cytokine signaling, and immune checkpoint expression, ultimately contributing to immune evasion. Targeting these epigenetic mechanisms with specific inhibitors such as EZH2 and HDAC inhibitors in combination with immunotherapy represents a compelling strategy to remodel the TME, potentially overcoming immune evasion and enhancing therapeutic outcomes in TNBC. This review aims to comprehensively elucidate the current understanding of epigenetic modulation in TNBC, its influence on the TME, and the potential of combining epigenetic therapies with immunotherapy to overcome the challenges posed by this aggressive breast cancer subtype.
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Quantum‐dot‐tagged reduced graphene oxide (QD‐rGO) nanocomposites (left) internalized into targeted tumor cells display bright fluorescence from the QDs (right); by absorbing NIR radiation incident ...on the rGO and converting it into heat, they also cause simultaneous cell death and fluorescence reduction (bottom). The nanocomposite is thus capable of tumor imaging, photothermal therapy and in situ monitoring of treatment in progress.
ortho‐Methyl effects are exploited to tune steric hindrance between side‐chain N,N′‐diaryls and polycyclic dihydrodibenzoa,cphenazine, and in turn control the conformations of ...N,N′‐diphenyl‐dihydrodibenzoa,cphenazine (DPAC) and its ortho‐methyl derivatives Mx‐My (x=0, 1 or 2, y=1 or 2, x and y correlate with the number of methyl groups in the ortho‐positiond of N,N′‐diphenyl). The magnitude of steric hindrance increases as x and y increase, and the V‐shaped dihydrodibenzoa,cphenazine skeleton is gradually tuned from a bent (DPAC) to planar (M2‐M2) structure in the ground state. As a result, the relaxation of the excited‐state structure of DPAC and its numerous analogues could be mimicked by model structures Mx‐My, demonstrating for the first time the the conformation change from bent‐to‐planar and hence a large range of energy‐gap tuning of polycyclic conjugated structures controlled by the steric hindrance.
Six (D)PAC: ortho‐Methyl effects are exploited to tune the steric hindrance between side‐chain N,N′‐diaryls and polycyclic dihydrodibenzoa,cphenazine, and in turn control the conformation and color of N,N′‐diphenyl‐dihydrodibenzoa,cphenazine (DPAC) and its ortho‐methyl derivatives. The results show that simple insertion of a small methyl group overcomes the energy barrier to planarization in the ground state.
An on-field colorimetric sensing strategy employing gold nanoparticles (AuNPs) and a paper-based analytical platform was investigated for mercury ion (Hg2+) detection at water sources. By utilizing ...thymine–Hg2+–thymine (T–Hg2+–T) coordination chemistry, label-free detection oligonucleotide sequences were attached to unmodified gold nanoparticles to provide rapid mercury ion sensing without complicated and time-consuming thiolated or other costly labeled probe preparation processes. Not only is this strategy’s sensing mechanism specific toward Hg2+, rather than other metal ions, but also the conformational change in the detection oligonucleotide sequences introduces different degrees of AuNP aggregation that causes the color of AuNPs to exhibit a mixture variance. To eliminate the use of sophisticated equipment and minimize the power requirement for data analysis and transmission, the color variance of multiple detection results were transferred and concentrated on cellulose-based paper analytical devices, and the data were subsequently transmitted for the readout and storage of results using cloud computing via a smartphone. As a result, a detection limit of 50 nM for Hg2+ spiked pond and river water could be achieved. Furthermore, multiple tests could be performed simultaneously with a 40 min turnaround time. These results suggest that the proposed platform possesses the capability for sensitive and high-throughput on-site mercury pollution monitoring in resource-constrained settings.
Tellurium is usually present at very low concentrations in environmental samples, which makes it a challenging element to measure in complex matrices. It exists mainly as Te(IV) and Te(VI) in natural ...waters and geological samples and its geochemistry is often compared to that of selenium, its upper neighbor in the periodic table of the elements. More than 145 papers that are related to tellurium in freshwaters, marine and estuarine systems, soils and sediments and air particulate maters, as well as various analytical techniques associated to this element, have been reviewed. Concentrations of total dissolved tellurium in open oceans are usually less than 2 ng/L (∼16 pM) and can increase by approximately one order of magnitude in non polluted freshwaters. Most tellurium compounds are considered toxic. Except from samples collected close to sources of contamination, tellurium concentrations in soils and sediments are normally at the low ppb (μg/g) level. In tellurium speciation studies, pre-concentration steps are often required in the analytical protocols. In fact very few studies have reported tellurium speciation in solid samples. Total tellurium reported in studies on aerosols and air particulates is usually below the ng/m3.
Heart disease is the leading cause of death worldwide. The major cause of heart failure is the death of the myocardium caused by myocardial infarction, detrimental cardiac remodeling, and cardiac ...fibrosis occurring after the injury. This study aimed at discovering the role of the anti-aging protein α-klotho (KL), which is the co-receptor of fibroblast growth factor-23 (FGF23), in cardiac regeneration, fibrosis, and repair. We found that the anti-apoptotic function of soluble KL in isoproterenol-treated H9c2 cardiomyocytes was independent of FGF23 in vitro. In vivo, isoproterenol-induced cardiac fibrosis and cardiomyocyte and endothelial cell apoptosis were reduced by KL treatment. Moreover, the number of Ki67-positive endothelial cells and microvessel density within the isoproterenol-injured myocardium were increased upon KL treatment. However, by using genetic fate-mapping models, no evident cardiomyocyte proliferation within the injured myocardium was detected with or without KL treatment. Collectively, the cardioprotective functions of KL could be predominantly attributed to its anti-apoptotic and pro-survival activities on endothelial cells and cardiomyocytes. KL could be a potential cardioprotective therapeutic agent with anti-apoptotic and pro-survival activities on cardiomyocytes and endothelial cells.
We have developed a one-pot approach to prepare fluorescent DNA-templated gold/silver nanoclusters (DNA-Au/Ag NCs) from Au3+, Ag+, and DNA (5′-CCCTTAATCCCC-3′) in the presence of NaBH4 in order to ...detect sulfide (S2‑) ions on the basis of fluorescence quenching. The as-prepared DNA-Au/Ag NCs have been characterized by UV–vis absorption, fluorescence, circular dichroism, X-ray photoelectron spectroscopy, and electrospray ionization-mass spectrometry measurements. Relative to DNA-Ag NCs, DNA-Au/Ag NCs are much more stable in high ionic strength media (e.g., 200 mM NaCl). The quantum yield of the as-prepared DNA-Au/Ag NCs is 4.5%. We have demonstrated that the fluorescence of DNA-Au/Ag NCs is quenched by S2‑ ions through the interaction between sulfide ions and gold/silver atoms/ions, a result which leads to changes in the conformation of the templated DNA from packed hairpin to random coil structures. These changes in fluorescence intensity allow sensitive detection of S2‑ ions at concentrations as low as 0.83 nM. To minimize interference from I– ions for the detection of S2‑ ions using the DNA-Au/Ag NCs, the addition of sodium peroxydisulfate to the solution is essential. We have validated the practicality of this probe for the detection of S2‑ ions in hot spring and seawater samples, demonstrating its advantages of simplicity, sensitivity, selectivity, and low cost.
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