[en] A simple, sensitive fluorescent method for detecting biological aminothiols has been developed based on the inner filter effect principle that utilizes CePO₄:Tb³⁺ luminescent nanoparticles as the donor and gold nanoparticles (AuNPs) as the energy receptor. Stable, water-soluble and well-dispersible CePO₄:Tb³⁺ nanoparticles with low photobleaching features were synthesized conveniently by a facile solvothermal method. At the same time, AuNPs with a high extinction coefficient are expected to be capable of functioning as powerful receptor. Based on the complementary overlap between the emission spectrum of CePO₄:Tb³⁺ nanoparticles and the absorption spectrum of Au NPs, an inner filter effect system was constructed. In the presence of aminothiols (such as cysteine), AuNPs interacted with the aminothiols, thereby inducing the aggregation of AuNPs, which induced the fluorescence recovery. In the present work, we developed a turn-on fluorescent assay for the determination of biological aminothiols. Under the optimum conditions, the linear concentration ranges were 1.0×10⁻⁷–2.0×10⁻⁶ M for cysteine, 5.0×10⁻⁸–5.0×10⁻⁷ M for glutathione and 8.0×10⁻⁸–1.0×10⁻⁶ M for homocysteine, respectively. The method is successfully applied to the quantification of biological aminothiols in synthetic samples. -- Highlights: • An inner filter effect method for detecting biological aminothiols has been developed. • CePO₄:Tb³⁺ nanoparticles were synthesized and used as the donor. • Gold nanoparticles (AuNPs) were synthesized and used as the energy receptor

[en] Classical trigeminal neuralgia (TN) is one of the most common diseases of cranial nerves and characterized by recurrent episodes of severe electric shock-like pain in the sensory supply areas of trigeminal nerve, without an established etiology. Multimodal magnetic resonance imaging (MRI) techniques can fully evaluate the neurovascular contact at cisternal segment of trigeminal nerve, morphological changes of trigeminal nerve, fiber integrity of trigeminal nerve, structural and functional alternations in related brain areas, which can help to understand the pathogenesis of TN, guide development of treatment strategy and predict outcome of microvascular decompression. In this article, the technological progress and current development of multimodal MRI in classical TN were reviewed. (authors)

[en] Objective: To assess the diagnostic value of MSCT and MR perfusion in the differentiation of benign and malignant soft tissue tumors. Methods: Twenty-six patients with soft tissue tumors were studied in MSCT perfusion and 29 patients in MR perfusion. The differences of perfusion parameters of benign and malignant tumors were analyzed. Results: The average value of MSCT BF was (24.49 ± 14.49) ml·100 mg^-1 · min^-1 for malignant group, and (1.98 ± 1.19) ml·100 mg^-1 · min^-1 for benign group. PS was (14.64 ± 1.89) ml·100 mg^-1·min^-1 for malignant group, and (2.40 ± 0.38) ml·100 mg^-1·min^-1 for benign group. The mean BF and PS in benign and malignant tumors had significant difference in MSCT perfusion. The sensitivity , specificity, accuracy, positive predictive value, and negative predictive value of MSCT in estimating the potential malignancy of the tumors were 90.9%(10/11), 86.7%(13/15), 88.5%(23/26), 83.3%(10/12), and 92.9%(13/14), respectively. The average value of MR BF was (0.11 ± 0.02) ml·100 mg^-1·min^-1 for malignant group, and (0.07 ± 0.01) ml·100 mg^-1·min^-1 for benign group. The mean BF in benign and malignant tumors has significant difference in MR perfusion. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR in estimating the potential malignancy of the tumors were 91.7%(11/12), 88.2%(15/17), 89.7%(26/29), 84.6%(11/13), and 93.8%(15/16), respectively. Conclusion: MSCT and MR perfusion are very helpful in the differentiation of benign soft tissue tumors from malignant ones. (author)

[en] Objective: To evaluate the MRI findings of mesenteric hemangioma, and to improve the knowledge of the tumor. Methods: MRI data of a patient with mesenteric hemangioma proved by pathology was analyzed, and literatures were reviewed. Results: MRI scan revealed a huge solid-cystic and multilocular mass, which distributed in fan-shaped pattern in hypogastrium and pelvic. The mass presented mixed signals on T₁WI, T₂WI, and spectral presaturation attenuated inversion recovery (SPAIR). It showed multiple linear separated honeycomb like changes within the lesion. The edge of lesions on T₂WI also showed multiple small vascular flow void. Adjacent tissues were compressed. There was a close relationship between the mass and intestine. Conclusion: Mesenteric hemangioma has specific MRI findings. Understanding its radiological characteristics and information of mesenteric anatomy could improve the diagnosis of this disease. The final diagnosis relies on pathological examination. (authors)

[en] Abnormal fat metabolism plays an important role in the initiation and development of systemic metabolic diseases and inflammation response, which can lead to multiple organ dysfunction. Traditional methods for analyzing adipose tissue (AT) are all invasive approaches. Multimodal magnetic resonance imaging (MRI) can provide a comprehensive assessment of the function of AT, ectopic fat deposition, and can provide abundant information for diagnosis, monitoring disease progression, and evaluation of therapeutic efficacy of metabolic diseases. This article aimed to review technological advances and research application of multimodal MRI in quantitative evaluation of fat tissue and fatty liver. (authors)

[en] BOLD-fMRI has been an important approach of evaluating the status of myocardial ischemia noninvasively. The accuracy and reliability of evaluating myocardial ischemia using BOLD-fMRI have also been certified by previous studies. As the development of MR devices and sequences, BOLD-fMRI not only had the ability to diagnose the ischemia of myocardium quanlificationally, but also could detect viable myocardium noninvasively. (authors)

[en] Objective: To identify the neural mechanisms of impulsivity and the response inhibition deficits of the chronic heroin users using event-related functional MRI (stop-signal task). Methods: Seventeen individuals with heroin dependence and 17 healthy control subjects underwent fMRI scan while executing stop -signal task after anatomical scanning in 3.0 T scanner. The AFNI package was used for fMRI data preprocessing and statistical analysis. Results: The behavioral data showed that the stop signal reaction rime (SSRT) of heroin users was significantly longer than that of the control group. There was no significant difference in activation of the primary motor cortex and supplementary motor area between two groups. Comparing to the control group, heroin users had weaker activation in the right dorsal lateral prefrontal cortex, right inferior prefrontal cortex, and anterior cingulated cortex, but stronger activation in bilateral striatum and amygdala while behavioral inhibition needed. Conclusion: The results suggest that heroin users have significant changes within impulsivity and inhibitory network, where the right prefrontal cortex is considered as main region for inhibition, while the anterior cingulated cortex is associated with error monitoring, and the amygdale controls impulsivity and emotion. (authors)

[en] Five zinc(II) metal–organic frameworks, [Zn_3(344-pytpy)_2Cl_6]_n·n(H_2O) (1), [Zn(344-pytpy)(ox)]_n (2), [Zn_2(344-pytpy)(bdc)_2]_n·1.5n(H_2O) (3), [Zn_2(344-pytpy)_2 (sfdb)_2]_n·1.5n(H_2O) (4) and [Zn_3(344-pytpy)_2(btc)_2]_n·2n(H_2O) (5), (344-pytpy=4′-(3-pyridyl)-4,2′:6′,4″-terpyridine, H_2ox=oxalic acid, H_2bdc=1,4-benzenedi-carboxylic acid, H_2sfdb=4,4′-sulfonyldibenzoic acid and H_3btc=1,3,5-benzene-tricarboxylic acid) have been prepared by hydrothermal reactions. Compound 1 is a 1D chain structure, in which 344-pytpy ligand links three Zn"I"I centers through three of terminal N-donors. Compound 2 is a 4-connected 3D framework with the dia topological net and the Schläfli symbol of 6"6. Compound 3 displays a unusual 3-fold interpenetrating 3D coordination network which exhibits a new intriguing (3,3,4)-connected topological net with the Schläfli symbol of (4.8"2)(4.8"5)(8"3). Compound 4 features a two-fold interpenetrating 4-connected 2D framework with the sql topological net and the Schläfli symbol of (4"4.6"2). Compound 5 is a new self-interpenetrating (3,3,4,4)-connected topological net with the Schläfli symbol of (6.8"2)_2(6"2.8"2.10.12)(6"2.8"3.10)_2(6"2.8)_2. The luminescence properties of 1–5 have been investigated by emission spectra and they possess great thermal stabilities which can be stable up to around 400 °C. - Graphical abstract: Five new Zn(II) metal–organic frameworks based on dicarboxylate and terpyridyl derivative ligands have been synthesized by hydrothermal reactions, giving networks from 1D to 3D structures. The thermal stability and luminescent property have been investigated. - Highlights: • Five zinc(II) metal–organic frameworks have been prepared under hydrothermal conditions. • Their crystal and topological structures have been investigated. • The luminescent properties have been investigated. • They possess great thermal stabilities which can be stable up to around 400 °C

[en] Carbon nanodots doped with boron and nitrogen (BN-CDs) with an average diameter of around 11 nm were prepared by a hydrothermal approach using adenine and 3-aminobenzene boronic acid as the starting materials. The atomic ratio of boron to nitrogen atomic in the BN-CDs is approximately 1:1. This indicates that a large fraction of N atoms goes lost during preparation because the B/N ratio of the precursors is about 1:6. The BN-CDs display blue fluorescence (best measured at excitation/emission wavelengths of 305/380 nm) which is independent of the excitation wavelength. On exposure to hypochlorite anion, fluorescence is quenched and the color of the solutions changes from yellow to brown. Fluorescence drops linearly in the 0.1–1000 μM hypochlorite concentration range. The colorimetric response, best measured as the absorbance ratio at 236/260 nm, ranges from 0.3 to 4.0 mM. The color changes can be readily detected visually. The probe was applied to the determination of hypochlorite in living cells and in (spiked) tap water.

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[en] The authors describe the synthesis of fluorescent coral-like carbon nano-branched polymers (PCNBPs) co-doped with nitrogen and phosphorus. Uric acid and phosphoric acid act as nitrogen and phosphorus sources, respectively. The PCNBPs have a coral-like branched structure, are cross-connected, and < 20 nm in skeleton diameter. Their blue fluorescence, best measured at excitation/emission wavelengths of 330/425 nm, is quenched by mercury (II) ions due to the specifically restricted rigid conformation caused by the interaction of phosphorus, nitrogen, and oxygen groups on the surface of the PCNBPs. Fluorescence is selectivity quenched by Hg(II) but restored in addition of the hypertension drug captopril (CAP) in the range 50 nM to 40 μM concentration range. Fluorescence recovery is attributed to the effectively specific interactions between the thiol group of CAP and Hg(II). The method was applied to the determination of the concentration of Cap in pharmaceutical samples, and recoveries were between 97.6 and 105.1%. .