[en] Objective: To investigate the CT and radiographic findings, pathogenesis, and transform of fibrous cortical defect of bone (FCD). Methods: Fifty-eight cases (47 males, 11 females; mean age 14.1 years) with FCD were examined with radiography, and CT scanning was performed in 26 cases (33 foci), 6 underwent volume scanning and three-dimensional (3 D) reconstruction. All cases were followed up for 2-15 years. 6 of them were proved by surgery and pathology. Results: (1) Number: 65 bones were involved including 70 foci; (2) location: The attack rate of the distal metaphysis of the femur was 81.43% (57/70). In 63 foci the distance between the focus and epiphyseal line/board was less than 30 mm, and more than 30 mm in 7; (3) Imaging features: FCD presented as oval shadow (in radiography) or crateriform/dished indentation to bone marrow cavity and separated with sclerous line. The bony shell was not detected on the surface of defect and part of them had longitudinal crest. CT values of the lesions were 37-85 HU (mean 64 HU). The post margin of the defect attached by muscle shadow was 81.88% (29/33); (4) Follow-up: 18 foci showed spontaneous obliteration and they were divided into two types according to their appearance: pre-site ossification type and smooth-restored type. 3 foci enlarged and were proved to be non-ossifying fibroma by surgery. Conclusion: The surface of FCD doesn't have bony shell. The defects shows a tendency of spontaneous obliteration or doesn't change for a long time. Neither typical FCD nor FCD with crest foci transforms to non-ossifying fibroma

[en] Objective: To further improve the recognition to the imaging and histological findings and genetics characteristics of Fahr disease, and to analyze the pathogenesis of cystification. Methods: The epidemiological investigations were performed in 3 (2 females, 1 male) patients. Two patients were confirmed by surgicopathology combining with the clinical representation and laboratorial examination, 1 patient was diagnosed by the clinical and laboratorial examination. Combining with review of related literature, the histological features and pathogenesis of complications (including cystification and hemorrhage) and genetics characters were analysed. Results: The imaging examination demonstrated that Fahr disease mainly presented the symmetrical calcification in bilateral basal nuclei areas and subcortex in 3, furthermore, the bilateral calcification of dentatum in 1 and the unilateral in 1, the cystification in 2 (one in the right frontal lobe, the other in the left parietal lobe). The content of blood calcium and serum inorganic phosphorus was normal in the laboratorial examination. The pathological examinations revealed the siderocytes caused by chronic hemorrhage and some small vessels that most were hyalinosis and a few were fibrinoid necrosis, and that there were sand-like and irregular calcification inner or around vessel wall, thrombosis in vessel cavity and arteritis, and that hemosiderin aggregated in the cystic wall. Conclusion: Most of Fahr disease can be diagnosed according to the imaging features combining with laboratorial examination. The hemorrhage and cystification in the brain should be regarded as the complications of Fahr disease. CT has higher diagnostic value than X-ray plain film and MRI because of higher density resolution. (authors)

[en] Objective: To determine the radiologic features of lung complications after single-lung transplantation for end-stage emphysema. Methods: A 56-year-old male with end-stage emphysema received a left-lung transplantation in our hospital on 28 Sep. 2002. The surgical technic used was similar to that mentioned in the literature. The chest radiography and CT scan were conducted to detect the thoracic imaging changes during perioperation period. Results: Reperfusion edema, also known as the reimplantation response, occurred in the lung allograft immediately after transplantation and was resolved in the first few days. There was a hyperinflation and pneumonia of the native lung at the first few days. The patient weaned from ventilator on the 93 hours after operation. Immunosuppression included cyclosporine, mycophenolate mofetil and corticosteroid. The acute rejection occurred on the 9^th day after operation and was cured by bolus methylprednisolone given intravenously. His lung function was improved significantly and he was discharged from hospital 47 days after operation. After discharge from the hospital, the patients could return to an almost normal life. Conclusion: Thoracic imaging has proved useful in the diagnosis of complications of single-lung transplantation for end-stage emphysema

[en] Ionic liquid (IL)-modified UiO-66-NH₂ composite was prepared and used as sorbent of dispersed solid-phase extraction (dSPE) for extracting trace benzoylurea insecticides (BUs) from complex environmental matrices. The IL in framework endowed the prepared material had electropositive characteristics, which can produce interaction with electron rich guest molecules, such as BUs. The high thermal and chemical stability of UiO-66-NH₂/IL enabled it to be reused for 16 times without significant reduction in adsorption performance. Due to the multiple forces including π-π, hydrogen bonding, and fluorine-fluorine interaction, UiO-66-NH₂/IL showed good adsorption performance, short adsorption time (20 s) and rapid desorption ability (60 s) for BUs. Under the optimal conditions, the method exhibited wide linear range (0.02–500 ng mL^-1) with correlation coefficient (R²) not worse than 0.9928, high enrichment factor (252–300), and low detection limit (0.005–0.4 ng mL^-1). The dispersed solid phase extraction coupling with high-performance liquid chromatography-diode array detector (dSPE-HPLC-DAD) was successfully used to detection of BUs in real environmental samples and satisfactory recoveries were obtained (80.5%±2.4–118%±3.2). The results indicated that UiO-66-NH₂/IL composite can be a potential sorbent for the preconcentration of trace insecticides in environmental samples. Graphical abstract

[en] This paper established a multi-objective optimization model of radioactive airborne effluent discharge limits and emissions assignment for multi-reactor sites. The applications of this model at multi-reactor sites in defining discharge limits and in operations management were then discussed. A case study of the Qinshan multi-reactor sites indicated that the model not only benefits the radiation protection optimization, but also has a strong operability in the optimal management of emission assignment. (authors)

[en] Using MIL-101(Fe) as the source of carbon and Fe, a magnetic porous carbon (MPC) material with Fe₃C nanoparticles encapsulated in porous carbon was prepared through one-pot pyrolysis under N₂ atmosphere. With MPC as adsorption material, a stir bar sorptive-dispersive microextraction (SBSDME) method was proposed to extract and preconcentrate sulfonamides (SAs) prior to HPLC-DAD determination. To investigate their extraction ability, different MPC materials were prepared under different carbonization temperatures (600, 700, 800, 900, and 1000 °C). The material prepared under 900 °C (MPC-900) exhibited the highest extraction ability for SAs. The as-prepared MPC materials were also characterized by Raman spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, zeta potential, and other techniques. The main parameters that affect extraction were systematically studied. Under optimal conditions, favorable linearity (R² ≥ 0.9938) and detection limits (0.02–0.04 ng mL⁻¹) of sulfonamides were obtained. The average recoveries for spiked milk and lake water samples ranged from 76.9 to 109% and from 75.4 to 118% with RSDs of 3.10–9.63% and 1.71–11.3%, respectively. Sulfameter and sulfisoxazole were detected in milk sample. Sulfisoxazole was detected in the lake water sample. The MPC-900 material demonstrated excellent reusability. It can be reused 24 times with peak areas having no obvious decline. The method can be applied to extract ultra-trace compounds in complex sample matrices. Graphical abstract:

[en] Mesoporous graphitic carbon nitride (MCN) is shown to be a viable sorbent for the enrichment of sulfonamides (SAs). To overcome the difficulty of separating the sorbent from the matrix, a novel type kind of column-assisted dispersive solid-phase extraction (CA-dSPE) method was designed. The MCN was characterized by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, fourier transform infrared spectroscopy and nitrogen adsorption-desorption measurements. The amount of sorbent, the pH value of the sample, the adsorption time, type and volume of the eluent and desorption time were optimized. The SAs were eluted from the sorbent with elution solvent of methanol containing 10% (v/v) ammonia and then submitted to HPLC analysis. Under the optimized conditions, the limits of detection for the SAs investigated (sulfadiazine, sulfameter, sulfachloropyridazine, sulfabenzamide and sulfadimethoxine) range from 20 to 5 pg·mL⁻¹. Satisfactory recoveries were obtained for spiked environmental water (90.1–110.5%) and milk samples (82.3–102.7%), with relative standard deviations of 0.5–3.8% and 1.1–4.4%, respectively. The method is simple, time saving and sensitive.

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[en] The monodispersed mesoporous SiO₂@metal-organic framework (MSN@MIL-101(Fe)) composites were prepared by grafting MSN-NH₂ onto MIL-101(Fe) particles with a solvothermal method. The adsorption ability of the composites was greatly improved compared to that of pristine MSNs or MIL-101(Fe) for phytohormones (Phys). The MSN@MIL-101(Fe) composites were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive spectrometer, and mapping analysis. Using MSN@MIL-101(Fe) composites as sorbent, a dispersive solid-phase extraction procedure (dSPE) was developed to extract three endogenous Phys (abscisic acid (ABA), indole-3-aceticacid (IAA), and indole-3-butyric acid (IBA)) and two exogenous Phys (1-naphthylacetic acid (1-NAA) and 2-naphthylacetic acid (2-NAA)) prior to HPLC-DAD analysis. The experimental parameters including sample volume, sorbent amount, adsorption time, adsorption pH, desorption time, and desorption solvent on extraction efficiency were optimized and evaluated. Under optimized conditions, the working range of 0.08 to 0.45 ng mL⁻¹ with enrichment factors from 144 to 207 were achieved. The linear range is 0.75–200 ng mL⁻¹ for IAA, 0.20–200 ng mL⁻¹ for ABA, and 1.0–200 ng mL⁻¹ for IBA, 1-NAA, and 2-NAA. With MSN@MIL-101(Fe) as sorbent for extraction of Phys and determination by HPLC-DAD, two endogenous Phys (IAA and ABA) were detected from mung bean sprouts which were made in a laboratory, and the results were further confirmed by high-resolution mass spectrometry. The composites can be applied to extract other small molecules, which have similar chemical structures with Phys in biological, environmental, and food samples.

[en] The authors report on a competitive potentiometric immunoassay for aflatoxin B₁ (AFB₁) in food that displays distinctly improved sensitivity. Gold nanoparticles (AuNPs; 16 nm i. d.) were functionalized with polyclonal anti-AFB₁ antibody (pAb), whilst the sensor electrode was prepared by immobilizing AFB1-bovine serum albumin conjugate (AFB1-BSA) on a glassy carbon electrode. Upon addition of target AFB₁, competitive immunobinding occurs between the analyte and AFB₁-BSA for the labeled pAb on the AuNPs. The change in the surface charge as a result of the antigen-antibody reaction causes a shift in the electrical potential. With increasing concentrations of analyte (AFB₁), the quantity of pAb-AuNP captured by the electrode decreases. The shift in the output potential is linearly proportional to the logarithm of AFB₁ concentration in the 0.1 to 5.0 μg · kg⁻¹ range, with a detection limit (LOD) of 87 ng · kg⁻¹ (87 ppt). An intermediate precision of 10.9 % was accomplished in batch-to-batch identification. The selectivity over AFB₂ with similar chemical structure is acceptable. The method accuracy was evaluated by analyzing naturally contaminated and spiked peanut samples, giving consistent results (with RSD values of <12 %) between this immunoassay and the commercial ELISA. (author)

[en] Highlights: • An isothermal, label-free and ultrasensitive aptasensor for kanamycin was constructed. • An impressive detection limit of 36 fM toward kanamycin could be achieved. • Strand displacement amplification was coupled with hybridization chain reaction for signal amplification. - Abstract: This work reports the proof-of-concept of an ultrasensitive label-free electrochemical aptasensor for Kanamycin (Kana) detection coupling strand-displacement amplification (SDA) with hybridization chain reaction (HCR). In the presence of target Kana, the analyte triggers conformational change of hairpin HP1 (HP1) and two-staged SDA to produce short single-stranded DNA (S1) with the aid of KF polymerase and nicking endonuclease. Meanwhile, the as-produced S1 hybridizes with the immobilized hairpin HP2 (HP2) on the electrode to open the hairpin, thereby resulting in the formation of DNA duplex. Thereafter, DNA duplex is selectively digested by Exo III accompanying S1 recycling. The residual single-stranded probe (S2) on the electrode opens another two hairpins in sequence and propagates a chain reaction of hybridization events between two alternating hairpins (H1 and H2) to form a long nicked double-helix. Upon addition of redox-active methylene blue (MB), numerous indicators are intercalated into the grooves of double-helix DNA polymers, each of which produces an electrochemical signal within the applied potentials. Under optimum conditions, the SDA/HCR-based electrochemical aptasensor exhibits a high sensitivity for detection of Kana down to 36 fM with a linear range from 0.05 to 200 pM. Additionally, the as-prepared aptasensor is successfully employed to determinate the Kana in animal derived food (milk). With the advantages of high sensitivity, label-free strategy and excellent selectivity, the developed aptasensor possesses great potential application value in food-safety analysis field.