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TiO2 is a semiconductor material used in photoelectric conversion. In order to improve its light utilization rate, nickel sulfide and silver nanoparticles were synthesized on the surface of titanium dioxide nanowires by simple impregnation-deposition and photoreduction methods. A series of studies were conducted on the cathodic protection effect of Ag/NiS/TiO2 nanocomposites on 304 stainless steel, with additional analyses on the material's morphology, composition, and light absorption characteristics. The results indicate that when the number of nickel sulfide impregnation-deposition cycles is 6, and the silver nitrate photoreduction concentration is 0.1 M, the prepared Ag/NiS/TiO2 nanocomposites can provide the best cathodic protection for 304 stainless steel.

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FeS2/TiO2 nanotube array composite films with clean, high efficiency, low cost and low consumption were prepared by electrochemical anodization and hydrothermal methods. The modification of FeS2 nanoparticles on the surface of TiO2 nanotube array film not only broadens the light absorption range of TiO2, but also improves the utilization ratio of visible light and the separation rate of photogenerated electron-hole pairs, which greatly improves the photoelectrochemical cathodic protection performance of TiO2 for 304 stainless steel (304SS). Under visible light irradiation, the open circuit potential of 304SS coupled with the FeS2/TiO2 nanocomposite films decreased from - 170 to - 700 mV, and the electrode potential can still maintained at - 400 mV after the light was turned off. Compared with pure TiO2 nanotube array film, FeS2/TiO2 nanocomposite film has better photoelectrochemical cathodic protection effect on 304SS in 3.5 wt% NaCl corrosion medium.

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BACKGROUND: LncRNAs play important roles in papillary thyroid carcinoma (PTC). LINC02471 has been reported to be related to PTC prognosis. The current study aimed to investigate the effects of LINC02471 on human PTC cells. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to examine LINC02471 expression in PTC tissues and cells and miR-375 expression in PTC cells. SiLINC02471, miR-375 mimic and miR-375 inhibitor were used for cell transfection. Cell proliferation, apoptosis, migration, and invasion were detected by performing Cell Counting Kit-8 (CCK-8), clone formation assay, flow cytometry, scratch assay, and transwell assay. Western blot was carried out to detect protein levels of E-cadherin, N-cadherin and Snail. The target gene for LINC02471 was verified by dual-luciferase reporter assay. RESULTS: LINC02471 was highly expressed in PTC tissues and cells. After silencing LINC02471, cell proliferation, migration and invasion were reduced, but cell apoptosis was increased. SiLINC02471 increased the expressions of E-cadherin and miR-375, and inhibited the expressions of N-Cadherin and Snail. LINC02471 directly targeted miR-375 in PTC cells. Overexpression of miR-375 inhibited the proliferation, migration, invasion of PTC cells and reduced the expressions of N-Cadherin and Snail but promoted the cell apoptosis and increased E-cadherin expression, while miR-375 inhibitor produced opposite effects to overexpressed miR-375. After inhibiting miR-375 expression, siLINC02471 reversed the effect of miR-375 inhibitor. CONCLUSION: LINC02471 could promote the development of PTC. Knocking down LINC02471 could inhibit invasion and metastasis and promote PTC cell apoptosis through directly targeting miR-375.

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OBJECTIVE: The purpose of this study was to evaluate the diagnostic value of clinical parameters and parathyroid scintigraphy for asymptomatic primary hyperparathyroidism (aPHPT), including quantitative parameter of laboratory and semiquantitative parameters derived from technetium-99m- metoxyisobutylisonitrile (99mTc-MIBI) single photon emission computed tomography/computed tomography (SPECT/CT). SUBJECTS AND METHODS: Two hundred and fourteen patients who had been diagnosed as PHPT and underwent surgical treatment were enrolled in this study. All patients were divided into two groups: aPHPT and symptomatic PHPT (sPHPT). Dual tracer 99mTc pertechnetate/99mTc-MIBI, dual time point and tomography scintigraphy with 99mTc-MIBI SPECT/CT were performed. Clinical parameters included basic information, serum calcium (Ca), phosphorus (P), parathyroid hormone (PTH) and alkaline phosphatase (ALP) levels. Semiquantitative parameters of parathyroid scintigraphy included the average counts of early parathyroid (PT1), late parathyroid (PT2), early thyroid (T1) and late thyroid (T2), the ratio of PT1/ T1 (R1), the ratio of PT2/ T2 (R2), parathyroid washout (PTW=(PT1-PT2)/PT1) and retention index (RI=(R2-R1)/R1). P<0.05 was considered as statistically significant. RESULTS: A total of 167 aPHPT patients (46 males, 121 females) were studied. One hundred and seventy four One hundred and seventy four174 parathyroid glands were removed after operation: 146 (87.4%) lesions were adenoma, 12 (7.2%) lesions were hyperplasia and 1 (0.6%) lesion was adenocarcinoma. There were significant differences in previous history (P=0.000), echo of parathyroid (P=0.004), thyroid function (P=0.029), clinical course (Z=-3.422, P=0.001), 99mTc-pertechnetat thyroid uptake (TcTU) (Z=-2.126, P=0.033), serum Ca level (t=-2.926, P=0.004) and serum PTH level (Z=-3.028, P=0.002) between aPHPT and sPHPT. For patients with aPHPT, there were significant differences for serum Ca level (t=2.832, P=0.005), R2 (Z=-2.597, P= 0.009) and RI (Z=-2.100, P=0.036) between adenoma and hyperplasia, and serum Ca level in aPHPT patients with adenoma was significantly higher compared with patients with hyperplasia. The areas under the curve (AUC) of clinical course, TcTU, serum Ca and PTH levels were 0.662, 0.399, 0.642 and 0.645 respectively for differential diagnosis of aPHPT and sPHPT. The AUC of R2 and RI were 0.737 and 0.692 respectively for differential diagnosis of adenoma and hyperplasia in patients with aPHPT. The sensitivity, negative predictive value (NPV) and accuracy for diagnosing aPHPT combined 99mTc-MIBI SPECT/CT with ultrasound (US) were significantly higher than dual tracer, dual time point, 99mTc-MIBI SPECT/CT and US, which were 97.5%, 95.2% and 55.6% respectively. CONCLUSION: Laboratory inspection and semi-quantitative parameters of parathyroid scintigraphy had higher value for differential diagnoses of aPHPT and sPHPT, the same for adenoma and hyperplasia in patients with aPHPT. When combined 99mTc-MIBI SPECT/CT with US, the diagnostic efficiency would be significantly improved.

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Burkholderia sp. ZD1, aerobically utilizes 2-picolinic acid as a source of carbon, nitrogen and energy, was isolated. ZD1 completely degraded 2-picolinic acid when the initial concentrations ranged from 25 to 300mg/L. Specific growth rate (µ) and specific consumption rate (q) increased continually in the concentration range of 25-100mg/L, and then declined. Based on the Haldane model and Andrew's model, µmax and qmax were calculated as 3.9 and 16.5h-1, respectively. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) was used to determine the main intermediates in the degradation pathway. Moreover, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was innovatively used to deduce the ring cleavage mechanism of N-heterocycle of 2-picolinic acid. To our knowledge, this is the first report on not only the utilization of 2-picolinic acid by a Burkholderia sp., but also applying FT-ICR-MS and ATR-FTIR for exploring the biodegradation pathway of organic compounds.

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OBJECTIVE: Small intestine bacterial overgrowth (SIBO) may be a pathogenetic factor for irritable bowel syndrome (IBS). This syndrome cannot be explained by structural abnormalities and has no specific diagnostic laboratory tests or biomarkers. We studied quantitatively and semi-quantitatively, using lactulose hydrogen breath test (LHBT), small intestinal transit time (SITT) (99m)technetium-diethylene triamine pentaacetic acid ((99m)Tc-DTPA) in order to examine the mobility of small intestine as an indication of bacterial overgrowth in patients. METHODS: Eighty nine consecutive patients who met Rome criteria for IBS were retrospectively studied. According to the diagnostic criteria, all patients were divided into two groups: the SIBO group and the non-SIBO group. The tracer was a mixture of 10g lactulose, 37MBq (99m)Tc-DTPA and 100mL water. The patient drank the whole mixture during 1min and the SITT study started immediately. The SITT and the LHBT followed every 15min for up to 3h after emptying the urine bladder. Spearman's rank correlation was applied to assess the correlation of oro-cecum transit time (OCTT) between imaging and LHBT. The semi-quantitative index between the SIBO group and the non-SIBO group was analyzed with Wilcoxon's rank sum test. If there was significant group difference, the receiver operating characteristic (ROC) curve was used. P<0.05 was considered significant. RESULTS: The median and inter-quartile range for OCTT for the LHBT (OCTT-L) for all patients was 90min and 60min, respectively, and 75min and 45min for OCTT for the SITT study (OCTT-i). There was positive correlation between OCTT-L and OCTT-i at the 0.05 level (R=0.290, P=0.000). There were no differences in OCTT-i and in the rate of radioactivity (counts of regions of interest ROI) over the abdomen between the SIBO group and the non-SIBO group (P=0.116 and 0.290). There were significant differences in the temporal association of the hydrogen (H2) value with OCTT-i (H2-i) and OCTT-L between the two groups (P=0.000 and 0.000). The areas under the curve (AUC) of H2-i and OCTT-L were 0.749 and 0.138 respectively. CONCLUSION: Small intestinal transit time study using a lactose hydrogen breath test and (99m)Tc-DTPA is a real-time test for small intestine bacteria overgrowth in IBS patients and can be used as an indicator of the disease.

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OBJECTIVE: Carbon-11-raclopride (¹¹C-R) is a positron-emitting radiotracer successfully used for the study of cognitive control and widely applied in PET imaging. A simple automated preparation of ¹¹C-R by using the reaction of carbon-(11)-methyl triflate (¹¹C-MeOTF) or ¹¹C-methyl iodide (¹¹C-MeI) with demethylraclopride is described. METHODS: Specifically we used a simple setup applied an additional "U" reaction vessel for ¹¹C-MeOTf compared with ¹¹C-MeI and assessed the influence of several solvents and of the amount of the percussor for ¹¹C-methylation of demethylraclopride by the bubbling method. The reversal of retention order between product and its precursor has been achieved for ¹¹C-R, enabling collection of the purified ¹¹C-R by using the HPLC column after shorter retention time. RESULTS: By the improved radiosynthesis and purification strategy, ¹¹C-R could be prepared with higher radiochemical yield than that of the previous studies. The yield for ¹¹C-MeOTf was 76% and for ¹¹C-CH3I >26% and with better radiochemical purity (>99% based on both ¹¹C-MeOTf and ¹¹C-MeI) as compared to the previously obtained purity of ¹¹C-R using HPLC method with acetonitrile as a part of mobile phase. Furthermore, by using ethanol as the organic modifier, residual solvent analysis prior to human injection could be avoided and ¹¹C-R could be injected directly following simple dilution and sterile filtration. CONCLUSION: Improved radiosynthesis and HPLC purification in combination with ethanol containing eluent, extremely shortened the time for preparation of ¹¹C-R, gave a higher radiochemical yield and purity for ¹¹C-R and can be used for multiple and faster synthesis of ¹¹C-R and probably for other ¹¹C-labeled radiopharmaceuticals.

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