Pleckstrin homology and RhoGEF domain containing G4 (PLEKHG4) leads to the activation of RhoGTPases promoting the malignant phenotypes of thyroid cancer.

Thyroid cancer (TC) is one of the most common endocrine system cancers, and its incidence is elevating. There is an urgent need to develop a deeper understanding of TC pathogenesis and explore new therapeutic target for its treatment. This study aimed to investigate the effects of pleckstrin homology and RhoGEF domain containing G4 (PLEKHG4) on the progression of TC. Herein, 29 pairs of TC and adjacent tissues were used to assess the expression of PLEKHG4. A xenograft model of mouse was established by subcutaneously injected with TC cells. Lung metastasis model was established through left ventricular injection. The results revealed that PLEKHG4 was up-regulated in human TC tissues. PLEKHG4 level was correlated with clinicopathological parameters of TC patients. In vitro assays revealed that PLEKHG4 promoted TC cell proliferation, migration, invasion, and epithelial-mesenchymal transformation. Knockdown of PLEKHG4 led to the opposite effects, and the loss of PLEKHG4 enhanced the apoptosis ability and inhibited the stemness properties of TC cells. These findings were further confirmed by the in vivo growth and lung metastasis of TC tumor. Mechanistically, PLEKHG4 promoted the activation of RhoGTPases RhoA, Cdc42, and Rac1. The inhibitors of these RhoGTPases reversed the PLEKHG4-induced malignant phenotypes. Additionally, ubiquitin-conjugating enzyme E2O (UBE2O), a large E2 ubiquitin-conjugating enzyme acted as an ubiquitin enzyme of PLEKHG4, facilitated its ubiquitination and degradation. In conclusion, PLEKHG4, regulated by UBE2O, promoted the thyroid cancer progression via activating the RhoGTPases pathway. UBE2O/PLEKHG4/RhoGTPases axis is expected to be a novel a therapeutic target for TC treatment.

The association between Geriatric Nutritional Risk Index and the risk of Invasive Candidiasis in critically ill older adults.

BACKGROUND: Invasive candidiasis is the most common hospital-acquired fungal infection in intensive care units (ICU). The Geriatric Nutritional Risk Index (GNRI) score was developed to evaluate the nutritional status of elderly adults. We aimed to assess the association between the GNRI score and the risk of invasive candidiasis in elderly patients admitted to ICU. METHODS: Hospitalization information of elderly patients with invasive candidiasis was collected retrospectively from Medical Information Mart for Intensive Care (MIMIC) IV and MIMIC-III Clinical Database CareVue subset from 2001 to 2019. The main outcome of this study was the diagnosis of invasive candidiasis in patients. We employed a multivariable Cox regression and propensity score matching to balance the influence of confounding factors on the outcome. Furthermore, we conducted sensitivity analyses by categorizing the GNRI into classes based on thresholds of 98, 92, and 81. RESULTS: A total of 6739 patients were included in the study, among whom 134 individuals (2%) were diagnosed with invasive candidiasis. The GNRI scores of patients with invasive candidiasis upon admission to the ICU were significantly lower, measuring 88.67 [79.26-98.27], compared to the control group with a score of 99.36 [87.98-110.45] (P < 0.001). The results of the multivariable Cox regression analysis demonstrated a strong association between higher GNRI scores and a decreased risk of invasive candidiasis infection (HR: 0.98, 95% CI: 0.97-0.99, P = 0.002). Consistently, similar results were obtained when analyzing the propensity score-matched cohort (HR: 0.99, 95% CI: 0.98-1, P = 0.028). Sensitivity analyses further confirmed a significantly increased risk of invasive candidiasis infection with lower GNRI scores. Specifically, the following associations were observed: GNRI ≤ 98 (HR: 1.83, 95% CI: 1.23-2.72, P = 0.003), GNRI ≤ 92 (HR: 1.68, 95% CI: 1.17-2.4, P = 0.005), 82 ≤ GNRI ≤ 92 (HR: 1.63, 95% CI: 1.01-2.64, P = 0.046), GNRI ≤ 81 (HR: 2.31, 95% CI: 1.44-3.69, P < 0.001). CONCLUSIONS: Lower GNRI score was significantly associated with an increased risk of invasive candidiasis in elderly patients in ICU. Further research is needed to validate whether improving nutrition can prevent invasive candidiasis.

Colorimetric and visual determination of uric acid based on decolorization of manganese dioxide nanosheet dispersions.

Serum levels of uric acid (UA) play an important role in the prevention of diseases. Developing a rapid and accurate way to detect UA is still a meaningful task. Hence, positively charged manganese dioxide nanosheets (MnO2NSs) with an average latter size of 100 nm and an ultra-thin thickness of below 1 nm have been prepared. They can be well dispersed in water and form stable yellow-brown solutions. The MnO2NSs can be decomposed by UA via redox reaction, leading to a decline of a characteristic absorption peak (374 nm) and a color fading of MnO2NSs solution. On this basis, an enzyme-free colorimetric sensing system for the detection of UA has been developed. The sensing system shows many advantages, including a wide linear range of 0.10-50.0 µmol/L, a limit of quantitation (LOQ) of 0.10 µmol/L, a low limit of detection (LOD) of 0.047 µmol/L (3σ/m), and rapid response without need of strict time control. Moreover, a simple and convenient visual sensor for UA detection has also been developed by adding an appropriate amount of phthalocyanine to provide a blue background color, which helps to increase visual discrimination. Finally, the strategy has been successfully applied to detect UA in human serum and urine samples.

The efficacy of immunosuppressive drugs induction therapy for lupus nephritis: a systematic review and network meta-analysis.

OBJECTIVE: This study was to assess the safety and effectiveness of immunosuppressive agents, specifically Voclosporin, when used in conjunction with mycophenolate mofetil (MMF) induction therapy for the management of lupus nephritis (LN). METHODS: A systematic review and network meta-analysis (NMA) was conducted on randomized controlled trials investigating the efficacy of immunosuppressant-induced therapy for LN. The random effects model was used in the analysis. I2 was used to evaluate the heterogeneity of the model. Odds ratios (OR) and 95% credible intervals (CrI) were computed to assess and compare the relative effectiveness and safety of various treatment protocols. RESULTS: The study included a total of 16 randomized controlled trials (RCTs) involving 2444 patients with LN. The analysis results indicated that there was no significant difference in terms of partial remission (PR) between the drugs. However, when considering complete remission (CR), the combination of Voclosporin with MMF showed the highest remission rate, followed by Tacrolimus (TAC). Unfortunately, Voclosporin in combination with MMF had the highest risk of infection and serious infection, indicating a lower safety profile. CONCLUSIONS: Voclosporin in combination with MMF demonstrated the highest efficacy as an induction therapy for LN. However, it should be noted that the risk of infection and serious infection was found to be high with this regimen. On the other hand, TAC not only showed efficacy but also had a lower risk of infection and serious infection, making it a favorable option in terms of safety. This study did' not include results on other adverse events.

Evaluation and comparison of multi-omics data integration methods for cancer subtyping.

Computational integrative analysis has become a significant approach in the data-driven exploration of biological problems. Many integration methods for cancer subtyping have been proposed, but evaluating these methods has become a complicated problem due to the lack of gold standards. Moreover, questions of practical importance remain to be addressed regarding the impact of selecting appropriate data types and combinations on the performance of integrative studies. Here, we constructed three classes of benchmarking datasets of nine cancers in TCGA by considering all the eleven combinations of four multi-omics data types. Using these datasets, we conducted a comprehensive evaluation of ten representative integration methods for cancer subtyping in terms of accuracy measured by combining both clustering accuracy and clinical significance, robustness, and computational efficiency. We subsequently investigated the influence of different omics data on cancer subtyping and the effectiveness of their combinations. Refuting the widely held intuition that incorporating more types of omics data always produces better results, our analyses showed that there are situations where integrating more omics data negatively impacts the performance of integration methods. Our analyses also suggested several effective combinations for most cancers under our studies, which may be of particular interest to researchers in omics data analysis.

Hybridizing aggregated gold nanoparticles with a hydrogel to prepare a flexible SERS chip for detecting organophosphorus pesticides.

Surface enhanced Raman scattering (SERS) is an ultrasensitive analytic technique. However, the application of SERS in quantitative analysis usually suffers from poor reliability due to the limitations of currently developed SERS substrates. In the present work, aggregated gold nanoparticles (a-AuNPs) fabricated by Ca2+-mediated assembly are dispersed in polyvinyl alcohol solution to prepare a novel hydrogel SERS chip through a physical crosslinking method. Taking advantage of the uniform distribution of SERS active a-AuNPs in the three-dimension hydrogel and the excellent barrier effect of hydrogel towards oxygen and macromolecules, the obtained hydrogel SERS chips show many outstanding advantages including high sensitivity, good repeatability, long-term stability, and a robust anti-interference ability. These advantages enable hydrogel SERS chips to be used to quantitatively analyse some complex samples without complex sample preprocessing. As a model, the hydrogel SERS chips are used for the detection of triazophos and phosmet in orange samples. The good recoveries suggest good applicability of the hydrogel SERS chips in food safety detection. This work provides a reliable and convenient platform for the quick detection and on-site monitoring of chemical contaminants and would promote greatly the performance of SERS techniques in quantitative analysis.

[Research Progress on Vector Flow Imaging of Cardiac Ultrasound].

Echocardiogram is vital for the diagnosis of cardiac disease. The heart has complex hemodynamics requiring an advanced ultrasound imaging mode. Cardiac ultrasound vector flow imaging is capable of measuring the actual magnitude and direction of the blood flow velocity, obtaining the quantitative parameters of hemodynamics, and then providing more information for clinical research and diagnosis. This study mainly reviewed several different vector flow imaging techniques for cardiac flow and presented the implementation difficulties, and proposed a diverging wave based high frame rate cardiac ultrasound vector flow imaging. The study discussed the limitation of current ultrasound technology used in the cardiac flow measurement, analyzed and demonstrated the specific reasons for these implementation difficulties and the potential future development.

Hybridizing Carbon-Based Dot-Capped Manganese Dioxide Nanosheets and Gold Nanoparticles as a Highly Sensitive Surface-Enhanced Raman Scattering Substrate.

Surface-enhanced Raman Scattering (SERS) is a sensitive and nondestructive technique that provides fingerprint structural information of molecules. Designing and constructing sensitive and stable SERS substrates is of great significance for the application of the technique. In this study, single-layer carbon-based dots (CDs) are used as capping agents to synthesize gold nanoparticles (AuNPs/CDs) and manganese dioxide nanosheets (MnO2/CDs), which are then hybridized through a simple cocentrifugation method. After the hybridization, the monodispersive AuNPs/CDs aggregate obviously into some clusters exhibiting strong SERS activity due to the electromagnetic "hot spots" effect, and the MnO2/CDs also show outstanding SERS activity due to the charge-transfer resonance effect. The obtained nanohybrids (MnO2/CDs/AuNPs) with robust chemical stability combine well with the electromagnetic enhancement of AuNPs/CDs and chemical enhancement of MnO2/CDs, leading to an ultrahigh enhancement factor of 3.9 × 108. Based on the novel SERS substrate, a sensitive and rapid sensing system for the detection of malachite green is developed, with a low detection limit of 1 × 10-9 M. This work provides a valuable model for designing and fabricating high-performance SERS substrates.

Single-Atom Ruthenium Biomimetic Enzyme for Simultaneous Electrochemical Detection of Dopamine and Uric Acid.

Single-atom catalysts have attracted numerous attention due to the high utilization of metallic atoms, abundant active sites, and highly catalytic activities. Herein, a single-atom ruthenium biomimetic enzyme (Ru-Ala-C3N4) is prepared by dispersing Ru atoms on a carbon nitride support for the simultaneous electrochemical detection of dopamine (DA) and uric acid (UA), which are coexisting important biological molecules involving in many physiological and pathological aspects. The morphology and elemental states of the single-atom Ru catalyst are studied by transmission electron microscopy, energy dispersive X-ray elemental mapping, high-angle annular dark field-scanning transmission electron microscopy, and high-resolution X-ray photoelectron spectroscopy. Results show that Ru atoms atomically disperse throughout the C3N4 support by Ru-N chemical bonds. The electrochemical characterizations indicate that the Ru-Ala-C3N4 biosensor can simultaneously detect the oxidation of DA and UA with a separation of peak potential of 180 mV with high sensitivity and excellent selectivity. The calibration curves for DA and UA range from 0.06 to 490 and 0.5 to 2135 µM with detection limits of 20 and 170 nM, respectively. Moreover, the biosensor was applied to detect DA and UA in real biological serum samples using the standard addition method with satisfactory results.

Mechanical stimuli-mediated modulation of bone cell function-implications for bone remodeling and angiogenesis.

Bone remodeling, expressed as bone formation and turnover, is a complex and dynamic process closely related to its form and function. Different events, such as development, aging, and function, play a critical role in bone remodeling and metabolism. The ability of the bone to adapt to new loads and forces has been well known and has proven useful in orthopedics and insightful for research in bone and cell biology. Mechanical stimulation is one of the most important drivers of bone metabolism. Interestingly, different types of forces will have specific consequences in bone remodeling, and their beneficial effects can be traced using different biomarkers. In this narrative review, we summarize the major mediators and events in bone remodeling, focusing on the effects of mechanical stimulation on bone metabolism, cell populations, and ultimately, bone health.

Tune the Fluorescence and Electrochemiluminescence of Graphitic Carbon Nitride Nanosheets by Controlling the Defect States.

The effects of defect states on the fluorescence (FL) and electrochemiluminescence (ECL) properties of graphite phase carbon nitride (g-CN) are systematically investigated for the first time. The g-CN nanosheets (CNNSs) obtained at different condensation temperatures are used as the study models. It can be found that all the CNNSs have two kinds of defect states, one is originated from the edge of CNNSs (labeled as CN-defect) and the other is attributed to the partially carbonization regions (labeled as C-defect). Both two kinds of defect states substantially affect the luminescent properties of CNNSs. Both the FL and ECL signals of CNNSs contain a band gap emission and two defect emissions. For the FL of CNNSs, decreasing the density of defect states can increase efficiently the FL quantum yield, while increasing the density of defect states can make the FL spectra red shift. For the ECL of CNNSs, increasing the density of CN-defect states and decreasing the density of C-defect states are greatly important to improve the ECL activity. This work provides a deep insight into the FL and ECL mechanisms of g-CN, and is of significance in tuning the FL and ECL properties of g-CN. Also, it will greatly promote the applications of CNNSs based on the FL and ECL properties.

A simple enzyme-catalyzed reaction induced "switch" type fluorescence biosensor based on carbon nitride nanosheets for the assay of alkaline phosphatase activity.

An enzyme-catalyzed fluorescence "switch" type sensor was constructed for the determination of alkaline phosphatase (ALP) activity by combining the fluorescence quenching effect of Ag+ on ultrathin g-C3N4 nanosheets (CNNSs) with the simple redox reaction of AA and Ag+. Briefly, Ag+ exhibits a significant quenching effect on the fluorescence of CNNSs. Thus the fluorescence signal of the CNNS-Ag+ system is extremely weak even in the presence of l-ascorbic acid-2-phosphate (AAP) ("off" state). When ALP coexists in the system, the enzyme can specifically catalyze the hydrolysis of AAP to form ascorbic acid (AA), which reduces Ag+ to Ag0. In this case, the fluorescence signal of the system is recovered ("on" state). Based on this principle, a signal-enhanced CNNS fluorescence sensor was developed to determine the activity of alkaline phosphatase. The experimental results show that the detection range of alkaline phosphatase is 0.5-20 U L-1, and the detection limit is 0.05 U L-1 (S/N = 3). Meanwhile, this method was used to assay ALP in serum samples.

Recent developments in strontium-based biocomposites for bone regeneration.

Recent advances in biomaterial designing techniques offer immense support to tailor biomimetic scaffolds and to engineer the microstructure of biomaterials for triggering bone regeneration in challenging bone defects. The current review presents the different categories of recently explored strontium-integrated biomaterials, including calcium silicate, calcium phosphate, bioglasses and polymer-based synthetic implants along with their in vivo bone formation efficacies and/or in vitro cell responses. The role and significance of controlled drug release scaffold/carrier design in strontium-triggered osteogenesis was also comprehensively described. Furthermore, the effects of stem cells and growth factors on bone remodeling are also elucidated.

Activating transcription factor 4 is required for high glucose inhibits proliferation and differentiation of MC3T3-E1 cells.

Activating transcription factor 4 (ATF4) promotes bone formation in human bone marrow mesenchymal stem cells. However, the underlying mechanisms of ATF4 in high glucose-induced injury of osteoblast still remain unclear. Small interfering RNA and plasmid targeting ATF4 were used to transfect MC3T3-E1 cells to knock down and overexpress ATF4 using Lipofectamin 3000. Cell viability, alkaline phosphatase (ALP) activity and levels were determined by MTT, ALP kit assay, quantitative real-time (qRT)-PCR and Western blot. Osteocalcin (OCN) expression was determined by ELISA, PCR and Western blot. The mRNA and protein levels of ATF4, glucose regulated protein 78 kDa (GRP78) and C/EBP homologous protein (CHOP) were detected by PCR and Western blot. In the current study, viabilities of MC3T3-E1 cells were inhibited by high glucose. Meanwhile, the mRNA and protein levels of ATF4 were effectively up-regulated in high glucose-incubated MC3T3-E1 cells. By conducting functional experiments, silencing ATF4 induced by small interfering RNA partially reversed the inhibitory effects of high glucose on viabilities of MC3T3-E1 cells. We also found that the expressions of ER stress-related proteins (ATF4, GRP78 and CHOP) were higher in high glucose-treated MC3T3-E1 cells but were inhibited by siATF4. However, overexpression of AFT4 had opposite results, and high glucose attenuated the protein levels of osteogenic marker genes ALP and OCN, which were further inhibited by ATF4 knockout gene. Thus, ATF4 was a necessary gene for high glucose to inhibit the proliferation and differentiation of MC3T3-E1 cells.

Nitrogen and Sulfur Co-doped Carbon-Dot-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry Imaging for Profiling Bisphenol S Distribution in Mouse Tissues.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI-TOF MSI) is rapidly maturing as an innovative technique for spatial molecule ( m/ z > 1000 Da) profiling. However, direct identification of low-molecular-weight compounds ( m/ z < 600 Da) by MALDI-TOF MSI using conventional organic matrixes remains a challenge because of ionization suppression and serious matrix-related background interference. Furthermore, the heterogeneous cocrystallization that is inherent to organic matrixes can degrade spatial resolution in MSI. Herein, we developed a negative ion surface-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (SALDI-TOF MSI) protocol to detect bisphenol S (BPS) and map its spatial distribution in mouse tissues by applying nitrogen- and sulfur-co-doped carbon dots (N,S-co-doped CDs) as a new matrix through spraying. The SALDI-TOF MS and imaging parameters, such as matrix concentration, ionization mode, and matrix deposition, were optimized to improve imaging performance. In comparison to organic matrixes, the use of N,S-co-doped CDs in negative ion mode exhibited free matrix background interference, enhanced MS signal intensity, and provided high spatial resolution (acquired at ∼50 µm) in the analysis of BPS, which allowed sensitive detection of the target compound on the surfaces of tissue sections. Quantitative assessment was also made by spotting BPS standards directly onto the tissue surface, and a good correlation between the color change and BPS concentrations was found. The corresponding detection limit as low as the ∼pmol level for BPS was observed with the direct visualization from MS images. Furthermore, the feasibility of the proposed SALDI-TOF MSI method was extended for in situ identification of exogenous BPS in the different tissues of mouse involving liver, kidney, spleen, and heart for exposure and profiling its spatial localization at different administration times. In addition, the general applicability of the proposed method was also evaluated by SALDI-TOF MSI analysis of BPAF in tissues. These successful applications of SALDI-TOF MSI not only demonstrated its promising potential as an alternative to MALDI-TOF MSI in profiling small molecules in tissue sections but also provided tremendous insight into the assessment of BPS exposure.

Effects of C-Related Dangling Bonds and Functional Groups on the Fluorescent and Electrochemiluminescent Properties of Carbon-Based Dots.

Single-layer carbon-based dots (SCDs) were chosen as a model to investigate the effect of the C-related dangling bonds with spin S=1/2 and functional groups on the electrochemiluminescent (ECL) and fluorescent (FL) properties of CDs. The C-related dangling bonds and functional groups of SCDs were tuned by chemical reduction with NaBH4 . There have several main findings via investigating the ECL and FL properties of SCDs before and after the chemical reduction. First, the FL and ECL of CDs are highly dependent on their concentration, and luminescent resonance energy transfer is observed in ECL studies when the concentration of CDs is high. Second, the ECL activity of CDs is greatly enhanced as the C-related dangling bonds increase, proving that the ECL of CDs originates from the C-related dangling bonds. Third, the FL of CDs is the synthesis of the inner FL originated from the contained isolated sp2 units and the defect FL from the C-related dangling bonds. The inner FL of CDs is enhanced greatly by removing the carboxyl groups, while the defect FL is increased slightly due to the increased C-related dangling bonds. We believe this study would promote our understanding in the ECL and FL mechanisms of CDs, advancing the applications of CDs based on their ECL and FL properties.

Colorimetric determination of glutathione by using a nanohybrid composed of manganese dioxide and carbon dots.

A kind of single-layer carbon based dots (CDs) with abundant carboxyl functional groups was hybridized with manganese dioxide (MnO2). The resulting nanohybrid is stable and can be well dispersed in water. MnO2 is capable of oxidizing the substrate 3,3'5,5'-tetramethylbenzidine (TMB) to form a blue product whose absorption (peaking at 655 nm) fades in the presence of glutathione (GSH). A sensitive and selective colorimetric GSH assay was worked out that has a linear response in the 10 to 0.1 µM GSH concentration range, with a 0.095 µM detection limit. The method was applied to the determination of GSH in spiked fetal calf serum where it gave excellent recoveries. Graphical abstract Schematic of the preparation of a nanohybrid composed of manganese dioxide and carbon based dots (MnO2/CDs). They can be used for the colorimetric detection of glutathione (GSH) based on the color change of 3,3'5,5'-tetramethylbenzidine (TMB).

Omega-3 PUFA ameliorates hyperhomocysteinemia-induced hepatic steatosis in mice by inhibiting hepatic ceramide synthesis.

Hyperhomocysteinemia (HHcy) is a key risk factor in hepatic steatosis. In this study, we applied a metabolomic approach to investigate the changes in the metabolite profile due to HHcy-induced hepatic steatosis and the effects of omega-3 PUFA (polyunsaturated fatty acid) supplementation in mice. HHcy was induced in mice by giving DL-Hcy (1.8 g/L) in drinking water for 6 weeks, then the mice were sacrificed, and the metabolic profiles of the liver and plasma were analyzed through UPLC-ESI-QTOFMS-based lipidomics. Hepatic triglycerides and cholesterol were further assayed. The expression of ceramide metabolism-related genes was measured by quantitative PCR. Compared with control mice, HHcy mice exhibited hepatic steatosis with a notable increase in ceramide-related metabolites and subsequent upregulation of ceramide synthesis genes such as Sptlc3, Degs2, Cer4 and Smpd4. Omega-3 PUFA was simultaneously administered in HHcy mice through chow diet containing 3.3% omega-3 PUFA supplement for 6 weeks, which significantly ameliorated Hcy-induced hepatic steatosis. The decrease in hepatic lipid accumulation was mainly due to reduced hepatic levels of ceramides, which was partly the result of the lower expression of ceramide synthesis genes, Sptlc3 and Degs2. Similar beneficial effects of DHA were observed in Hcy-stimulated primary hepatocytes in vitro. In summary, Hcy-induced ceramide elevation in hepatocytes might contribute to the development of hepatic steatosis. Furthermore, downregulation of ceramide levels through omega-3 PUFA supplementation ameliorates hepatic lipid accumulation. Thus, ceramide is a potential therapeutic target for the treatment of hepatic steatosis.

Dual-Emission of Lanthanide Metal-Organic Frameworks Encapsulating Carbon-Based Dots for Ratiometric Detection of Water in Organic Solvents.

Nitrogen and sulfur codoped carbon-based dots (N,S-CDs) with strong blue light emission are encapsulated into red light-emitting europium metal-organic frameworks (Eu-MOFs) to form two color light-emitting nanohybrids (Eu-MOFs/N,S-CDs). In organic solvents, the encapsulated N,S-CDs are aggregated and confined in the cavities of the Eu-MOFs, exhibiting only a very weak photoluminescence (PL) signal. Therefore, the nanohybrids show red light emission of the Eu-MOFs. Contrarily, when the Eu-MOFs/N,S-CDs are dispersed in water, the encapsulated N,S-CDs are released into solution while the red light emission of the Eu-MOFs is quenched due to the effect of O-H oscillators. The nanohybrids are used as the probe for the water content in organic solvents. Take ethanol as an example; as the water content is increased from 0.2 to 30%, the nanoprobe provides distinguishable PL color change. The ratio of light intensity at 420 nm to that at 623 nm (I420/I623) increases linearly with increasing water content in the range from 0.05 to 4% with a low detection limit of 0.03%.