Objective:To establish an inductively coupled plasma mass spectrometry (ICP-MS) method for the rapid determination of total bromine in whole blood, and to provide technical support for the monitoring of bromine exposure in occupational populations.Methods:In September 2023, 0.25 ml of whole blood sample was added with 0.25% tetramethylammonium hydroxide solution to a volume of 5.0 ml, ultrasonicated and homogenized, and then quantified by ICP-MS with rhodium solution as the online internal standard solution.Results:The linear relationship of bromine in blood was good within the range of 0~10.00 mg/L, with a correlation coefficient ( r) >0.999. The limit of detection of the method was 0.07 mg/L, and the quantification limit was 0.22 mg/L. The recoveries of the total bromine in whole blood were in the range of 95.5%-102.9%, and the relative standard deviations (RSDs) were in the range of 3.1%-4.7% ( n=7) . Conclusion:An ICP-MS method was established for the rapid determination of total bromine in whole blood, which is accurate, simple, rapid, highly automated, and can be used for the determination of total bromine in whole blood of occupationally exposed people.

Objective:To establish an inductively coupled plasma mass spectrometry (ICP-MS) method for the rapid determination of total bromine in whole blood, and to provide technical support for the monitoring of bromine exposure in occupational populations.Methods:In September 2023, 0.25 ml of whole blood sample was added with 0.25% tetramethylammonium hydroxide solution to a volume of 5.0 ml, ultrasonicated and homogenized, and then quantified by ICP-MS with rhodium solution as the online internal standard solution.Results:The linear relationship of bromine in blood was good within the range of 0~10.00 mg/L, with a correlation coefficient ( r) >0.999. The limit of detection of the method was 0.07 mg/L, and the quantification limit was 0.22 mg/L. The recoveries of the total bromine in whole blood were in the range of 95.5%-102.9%, and the relative standard deviations (RSDs) were in the range of 3.1%-4.7% ( n=7) . Conclusion:An ICP-MS method was established for the rapid determination of total bromine in whole blood, which is accurate, simple, rapid, highly automated, and can be used for the determination of total bromine in whole blood of occupationally exposed people.

Background The concentrations of disinfection by-products (DBPs) are varied by different water sources, disinfectants, or treatment processes in Wuxi, and the associated health risks are also different. Objective To understand the levels of trihalomethanes (THMs) and haloacetamides (HAcAms) in drinking water in Wuxi, and their variations by water sources, seasons, disinfectants or treatment processes, aiming to provide technical support for ensuring the safety of drinking water. Methods In dry period (December 2019) and wet period (July 2020), the finished water and tap water (from the beginning, middle, and end of the drinking water distribution network) from 12 centralized water treatment plants in Wuxi were collected to detect the concentrations of THMs and HAcAms in water samples. A purge and trap-gas chromatography-mass spectrometry method was applied to detect trichloromethane (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and tribromomethane (TBM), and a solid-phase extraction-gas chromatography-mass spectrometry method to detect dichloroacetamide (DCAcAm), trichloroacetamide (TCAcAm), bromochloroacetamide (BCAcAm), dibromoacetamide (DBAcAm), bromodichloroacetamide (BDCAcAm), dibromochloroacetamide (DBCAcAm), and tribromoacetamide (TBAcAm). Analyses and comparisons were made on the concentrations of THMs and HAcAms in drinking water by water sources (the Yangtze River/the Taihu Lake/reservoir), wet/dry seasons, disinfection methods (liquid chlorine/sodium hypochlorite), and treatment processes (conventional treatment/conventional+advanced treatment). Results A total of 96 drinking water samples were collected in Wuxi. THMs were positive in all the water samples (100%), with concentration ranging from 1.027 to 40.225 μg·L⁻¹ and the M (P₂₅, P₇₅) concentration being 24.782 (17.784, 30.932) μg·L⁻¹. None of the 4 THMs exceeded the standard limit of the Standards for drinking water quality (GB 5749-2022 ), and the order of the 4 THMs concentrations from high to low was TCM > BDCM > DBCM > TBM. Five of the 7 HAcAms were detected, the total concentration ranged from 0.137 to 3.288 μg·L⁻¹, and the M (P₂₅, P₇₅) was 0.808 (0.482, 1.704) μg·L⁻¹. The DCAcAm concentration was the highest (2.448 μg·L⁻¹), followed by BCAcAm, while TCAcAm and DBCAcAm were not detected. The M (P₂₅, P₇₅) of the total concentration of THMs in the drinking water from the Taihu Lake was 33.353 (26.649, 36.217) μg·L⁻¹, that of the Yangtze River was 27.448 (24.312, 31.393) μg·L⁻¹, and both were higher than the level of the reservoir [16.359 (2.305, 21.553) μg·L⁻¹] (P<0.05), while the M (P₂₅, P₇₅) of the total concentration of HAcAms in the drinking water from the Taihu Lake was 0.616 (0.363, 0.718) μg·L⁻¹, which was lower than those of the Yangtze River [0.967 (0.355, 2.283) μg·L⁻¹] and the reservoir [1.071 (0.686, 1.828) μg·L⁻¹] (P<0.05). There were no statistically significant differences in the total concentrations of THMs and HAcAms between wet season and dry season, or between different disinfection methods (P>0.05). The M (P₂₅, P₇₅) concentrations of THMs and HAcAms in drinking water after advanced treatment process involving ozone, activated carbon, and membrane were 20.565 (3.316, 27.185) μg·L⁻¹ and 0.623 (0.452, 1.286) μg·L⁻¹ respectively, and were lower than the corresponding values after conventional treatment process, 28.740 (23.431, 35.085) μg·L⁻¹ and 0.934 (0.490, 2.116) μg·L⁻¹ respectively (P＜0.05). Conclusion The concentrations of THMs and HAcAms in drinking water in Wuxi are generally at a low level. The levels of controlled THMs meet the requirements of national standards, and the levels of uncontrolled HAcAms as new DBPs are up to μg·L⁻¹. The concentrations of the two kinds of DBPs in drinking water vary by water sources. The concentrations of THMs and HAcAms produced by the advanced treatment process are lower than that by the conventional treatment process.

Objective:To establish a method for rapid determination of iodine in whole blood by direct alkali dilution inductively coupled plasma mass spectrometry (ICP-MS).Methods:Totally 0.50 ml whole blood sample was collected, and 2% ammonia and 0.01% Triton X-100 solution were added to constitute a total volume of 10.0 ml. After shaking to uniformity, 1.0 μg/ml rhodium and 20% isopropanol were used as on-line internal standard solution. The flow ratio of internal standard solution to the solution to be measured was 1∶16. The sample was quantitatively determined by ICP-MS. The linear range, limit of detection (LOD), accuracy and precision of the method were evaluated.Results:Iodine in whole blood could be determined and had a good linear relationship within the range of 0-200 μg/L, with correlation coefficient ( r) > 0.999. The LOD of the method was 0.1 μg/L, the limit of quantitation (LOQ) was 0.3 μg/L, the recovery rate of iodine in whole blood was 88.5%-106.1%, and the relative standard deviation was 2.2%-4.7% ( n=7). Conclusions:A method for rapid determination of iodine in whole blood by direct alkali dilution ICP-MS is successfully established. This method is accurate, simple, rapid, and highly automatic, and it can be widely applied in determination of iodine in whole blood.

Objective:To investigate the craniofacial features in patients with cleidocranial dysplasia (CCD).Methods:The facial features,cervical vertebral bone age and skeletal abnormalities of 8 patients with CCD were studied by analyzing facial photos,cephalo-metric and panoramic radiographs.Results:4 patients were in the early growth stage and the other 4 in the late period of development. The bossing forehead and inclined eye fissure were observed in all patients,but underdevelopment of midfaces were not obviously pres-ented in younger patients.Morphological abnormalities of craniofacial bones,such as ascending ramus,coronoid process,nasal bones and disappearence of gonial angle were observed in all patients.Conclusion:Some craniofacial malformations in patients with CCD may be presented earlier than underdeveloped midface,which can be helpful for early diagnosis of CCD.

OBJECTIVETo observe and evaluate the clinical performance of zirconia crowns made by CEREC inLab computer aided design/computer aided manufacturing(CAD/CAM) for posterior teeth.

METHODSA total of 242 patients were implanted with zirconia crowns fabricated by CEREC inLab CAD/CAM. The crowns were evaluated by Modified US Public Health Service criteria at baseline, 6, 12, 24, and 36 months. The chi-square test was used to analyze the survival rate.

RESULTSAll but five crowns were evaluated by an independent evaluator at baseline, 6, 12, 24, and 36 months. The survival rate declined with time. The A score percentage was above 85% at 36 months.

CONCLUSIONThe single zirconia crowns fabricated by CEREC inLab CAD/CAM demonstrate satisfactory clinical performance during a short period.

Objective To observe and evaluate the clinical performance of zirconia crowns made by CEREC inLab com-puter aided design/computer aided manufacturing(CAD/CAM) for posterior teeth. Methods A total of 242 patients were implanted with zirconia crowns fabricated by CEREC inLab CAD/CAM. The crowns were evaluated by Modified US Public Health Service criteria at baseline, 6, 12, 24, and 36 months. The chi-square test was used to analyze the survival rate. Results All but five crowns were evaluated by an independent evaluator at baseline, 6, 12, 24, and 36 months. The survival rate de-clined with time. The A score percentage was above 85% at 36 months. Conclusion The single zirconia crowns fabricated by CEREC inLab CAD/CAM demonstrate satisfactory clinical performance during a short period.

Cloning of flanking sequences of double-copy gene is a challenge in molecular biology. We developed a method to solve this problem by combining an optimized inverse PCR (iPCR) with TAIL-PCR. First, Southern blotting analysis was used to determine a proper restriction enzyme that could obtain proper-length restriction fragments that contained the target gene. Then optimized iPCR was performed to amplify the restriction fragments that contained the separated copies of the gene. Based on the obtained sequences, TAIL-PCR was performed to amplify further flanking regions of the gene. With this method, we obtained all of the EcoR I restriction fragments (2.2-5.1 kb) and Hind III restriction fragments (8.5-11.7 kb) of mitochondrial atpA gene in cytoplasmic male sterile (CMS) line and maintainer line of Upland cotton. The results showed that this method was an efficient approach to clone flanking sequences of double-copy gene.
Chromosome Walking ; Cloning, Molecular ; Gene Expression Regulation, Plant ; Genes, Mitochondrial ; Genes, Plant ; genetics ; Gossypium ; genetics ; Plant Proteins ; genetics ; metabolism ; Polymerase Chain Reaction ; methods ; Terminal Repeat Sequences