[en] Lentinula edodes were implanted with various nitrogen ions implantation dosage but the same energy in this study. The variations of growth rate of mycelium, mycelial biomass and the contents of lentinan(LNT) under various nitrogen ions implantation dosage were investigated. Three curves of implantation all take a 'saddle shape' with increasing N⁺ ion implanted doses. The growth rate of mycelium is high under low dosage of N⁺ implantation, but with the increment of dosage, the growth rate shows downtrend then began rising when the dosage reaching 1.5 x 10¹⁶ cm^-2. The mycelia biomass and the contents of LNT rise firstly and then fall with the increment of dosage, and they both reach maximum at the dosage of 4 x 10¹⁵ cm^-2 Some fluctuation exists in the process, so they both reach another peak at the dosage of 1.5 x 10¹⁶ cm^-2. During the liquid culture of Lentinula edodes, the variation of mycelial biomass, gross weight of shake-flask, pH and the contents of lentinan(LNT) has been studied. The consistency between the variation of mycelia biomass and gross weight of flask during the liquid culture has also been con- firmed. This result can be applied to the study on fermentation before and mutation. Thus a conclusion may be drawn that it is an effective way of mutation breeding by N⁺ ion implantation. (authors)

[en] Chinese scientists discovered the biological effect of ion beam implantation in the 1980s, and applied this method to the mutation breeding. The article gives a brief introduction to the theory of ion beam bio-technology, the biological effect of low energy ion beam and the progress of studies on ion beam bio-engineering in Xinjiang. (authors)

[en] Objective: To study the relationship between S. typhi R plasmid (pR_ST98) and macrophage apoptosis. Methods: pR_ST98 was transferred into a less virulent strain of S. typhimurium for creating a transconjugant pR_ST98/RIA, the standard S. typhimurium virulence strain SR-11 was used as the positive control, and RIA as the negative one. Infection with murine macrophage J_774A.1 occurred separately under the same conditions. J_774A.1 apoptosis was detected by flow cytometry and TUNEL at 0, 2, 4, 6, 12, 24 hours respectively. Mitochondria membrane potential was detected by JC-1 staining method. Viable bacteria was detected by serial dilution at the same time and viable cells stained with Trypan blue were counted. Results: SR-11 results in a higher apoptosis in J_774A.1 than pR_ST98/RIA, and a combined pR_ST98/RIA higher than RIA (P<0.05 or 0.01). Viable bacteria and cells were RIA>pR_ST98/RIA>SR-11 (P<0.05 or 0.01). Conclusions: The bacteria carried plasmid pR_ST98 could increase the macrophage apoptosis. (authors)

[en] In this paper, citric acid was used as carbon source, diethylenetriamine and urotropine were used as precursors, and N-doped carbon dots (cdh-CDs) with luminescent properties were synthesized by microwave method. The structure of the sample was analyzed by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffractometry (XRD), ultraviolet spectrophotometer (UV), fluorescence spectroscopy, etc., and it was proved that cdh-CDs with an amorphous structure about 4–10 nm in diameter was synthesized. The corrosion inhibition performance of cdh-CDs in 1 M hydrochloric acid was evaluated by static weight loss and electrochemical method. The results showed that cdh-CDs have a good corrosion inhibition performance at 60°C, the inhibition efficiency can reach 81.2% when the dosage is 600 ppm. Electrochemical results showed that cdh-CDs are mixed inhibitors which mainly inhibit cathodes.

[en] Objective: The aim of this study was to evaluate the value of SPECT/CT in detecting spine metastases using ⁹⁹Tc^m-methylene diphosphonic acid (MDP). Methods: A total of 76 patients with suspicious spine metastases underwent SPECT/CT ⁹⁹Tc^m-MDP imaging. Of these 76 patients, 19 were con- firmed by histopathology, 14 were endorsed by clinical follow up, and 43 were by CT and MRI. Results: Of these 76 patients, 28 were spine metastases and 48 were benign degenerative changes with SPECT/CT. Sensitivity of diagnosis of the metastatic bone tumor with SPECT/CT ⁹⁹Tc^m-MDP imaging in lesion of dorsal spine was 95.83% (23/24), specificity was 90.38% (47/52), accuracy was 92.11% (70/76), positive predictive value was 82.14% (23/28), negative predictive value was 97.92% (47/48), positive likelihood ratio was 9.97, negative likelihood ratio was 0.05. Conclusions: The diagnostic CT of SPECT/CT had adding value in providing detail anatomical information to SPECT in patients with suspicion bone metastasis. Such help may improve the diagnostic accuracy in differentiating benign from malignant lesion at spine. (authors)

[en] Objective: More studies have found that ⁹⁹Tc^m-MIBI thyroid imaging may provide more differential diagnostic value than traditional ⁹⁹Tc^mO₄^- thyroid imaging. This study attempted to analyze the receiver operating characteristic (ROC) curves to verify the additional diagnostic value of ⁹⁹Tc^m-MIBI over ⁹⁹Tc^mO₄^- thyroid imaging in the differentiation of the 'cold' nodules. Methods: Sixty-eight patients initially diagnosed with 'cold' nodules in ⁹⁹Tc^mO₄^- thyroid scintigraphy were selected for further ⁹⁹Tc^m-MIBI thyroid imaging at early (15 min after ⁹⁹Tc^m-MIBI intravenous injection, ER) and delayed phase (2 h after injection, DR). Semi-quantitative analysis was performed using tumor/normal tissue (T/N) ratio both at ER and DR, with 0.8 defined as the threshold for differential diagnoses. In ROC curves analyses, the ratios from tumor/submaxillary gland (T/S) and tumor/heart (T/H) were derived to obtain the most proper differential diagnostic thresholds. Results: Of all patients with the 'cold' nodules, only eight cases were finally diagnosed on pathology with thyroid malignancy, while other 60 were benign. For differential diagnoses, the sensitivity, specificity and accuracy of semi-quantitative ⁹⁹Tc^m-MIBI thyroid imaging were 100.0%, 76.7% and 79.4% respectively. However, with thresholds of T/N=0.995, T/S=0.995, T/H=1.005 derived from ROC curves for DR ⁹⁹Tc^m-MIBI imaging, the differential diagnostic sensitivities were 100.0%, 87.5%, 75.0% and the specificities were 90.0%, 85.0%, 83.3% respectively. The areas under the ROC curves were 0.949, 0.876 and 0. 867 respectively for DR, all significantly larger than those of ER. Statistical difference was also evident between threshold values of 0.8 and 0.995 (χ²=6.125, P<0.05). Conclusions: ROC curves derived from ⁹⁹Tc^m-MIBI thyroid imaging provide additional diagnostic value over ⁹⁹Tc^mO₄^- thyroid imaging for the differentiation of the 'cold' nodules. For ⁹⁹Tc^m-MIBI thyroid imaging, DR is more valuable than ER in the ROC curves analyses. (authors)

[en] Objective: To investigate the diagnostic values of ¹⁸F-FDG and 3'-deoxy-3'-¹⁸F-fluorothymidine (¹⁸F-FLT) PET/CT for solitary pulmonary nodules. Methods: ¹⁸F-FDG and ¹⁸F-FLT PET/CT imaging were performed in 40 patients with solitary pulmonary nodules. All cases were confirmed by pathology or follow-up. The diagnostic values of ¹⁸F-FDG SUV_max, ¹⁸F-FLT SUV_max, and ¹⁸F-FLT/the same level of vertebral SUV_max for pulmonary malignant tumor were compared using the receiver operating characteristic (ROC) curves. ¹⁸F-FDG and ¹⁸F-FLT imaging results were analyzed by visual observation and semi-quantitative analysis. The diagnostic efficiencies of the different diagnostic methods were compared. Results: Areas under the ROC curves of ¹⁸F-FDG SUV_max, ¹⁸F-FLT SUV_max, and ¹⁸F-FLT/same level of vertebral SUV_max were 0.687, 0.821, and 0.817, respectively. The diagnostic sensitivities, specificities, and accuracies of tested diagnostic tools were as follows: ¹⁸F-FDG SUV_max > 2.5 as the malignant diagnostic criteria, 88.2%, 73.9% and 80.0%; ¹⁸F-FLT SUV_max > 2.0 as the malignant diagnostic criteria, 58.8%, 82.6% and 72.5%; ¹⁸F-FDG PET/CT visual analysis of scoring method, 94.1%, 91.3% and 92.5%; and ¹⁸F-FLT PET/CT for visual analysis of scoring method 88.2%, 65.2% and 75.0%. Conclusions: ¹⁸F-FLT SUV_max and ¹⁸F-FLT/vertebral SUV_max showed higher accuracies in diagnosing solitary pulmonary modules compared with ¹⁸F-FDG SUV_max.¹⁸F-FDG PET/CT visual scoring method was the most effective in diagnosing solitary pulmonary nodules. (authors)

[en] In this paper, the phase segregation and thermo-mechanical properties of energetic poly(urethane–urea) (EPUU) for propellant binder application are analyzed. Series of EPUUs are synthesized from copolymer of 3,3-bis-azido methyl oxetane and tetrahydrofuran, tolylene diisocyanate, and 3,3′-dichloro-4,4′-dianilino methane, with different hard segment contents ranging from 9.7 to 38%. With the enlargement of hard segment content from 9.7 to 28.9% (EPUU1–EPUU3), the percentage of ordered part via hydrogen-bonded C=O in urea increases as investigated by FTIR, further increase of hard segment content to 38% results in less hydrogen-bonded ordered part but more disordered part. The SAXS result also verifies the highest degree of phase segregation of EPUU3. The thermo-mechanical properties of energetic poly(urethane–urea) are related to the degree of microphase separation. With the increase of hard segment content, the tensile strength increases roughly, while the elongation at break drops from EPUU1 to EPUU4. EPUU3 exhibits the highest value of tensile strength and acceptable elongation at break.

[en] A sensitive and rapid colorimetric biosensor has been developed for determination of amyloid-β peptide (Aβ) and study of amyloidogenesis based on the high peroxidase-like activity of porous bimetallic ZnO-Co₃O₄ nanocages (NCs). Due to the high binding ability of Aβ monomer to ZnO-Co₃O₄ NCs, the catalytic activity of ZnO-Co₃O₄ NCs can be significantly suppressed by Aβ monomer. This finding forms the basis for a colorimetric assay for Aβ monomer detection. The detection limit for Aβ monomer is 3.5 nM with a linear range of 5 to 150 nM (R² = 0.997). The system was successfully applied to the determination of Aβ monomer in rat cerebrospinal fluid. Critically, the different inhibition effects of monomeric and aggregated Aβ species on the catalytic activity of ZnO-Co₃O₄ NCs enabled the sensor to be used for tracking the dynamic progress of Aβ aggregation and screening Aβ inhibitors. Compared with the commonly used thioflavin T fluorescence assay, this method provided higher sensitivity to the formation of Aβ oligomer at the very early assembly stage. Our assay shows potential application in early diagnosis and therapy of Alzheimer's disease (AD).

[en] The cyanobacteria Prochlorococcus is a cyanbacterial genus, with some strains adapted to sea surface environments, which are poor in nutrients and have high-light intensity, and some strains adapted to deep sea conditions, which have relatively higher concentrations of nitrogen and phosphorus and lower light intensity. Here, we report pairwise comparisons between strains isolated from different depths of the same sea, which reveal a close association between atomic composition of the proteome and the availability nitrogen and phosphorus in the environment. The atomic composition of proteomes differs significantly among Prochlorococcus strains with different supplies of nitrogen in vivo; these different supplies result from different capacities for nitrogen assimilation. We repeated our whole-proteome analysis with the core proteomes of Prochlorococcus and obtained similar results. Our findings indicate that the elemental composition of proteomes is shaped by the availability of resources in the environment