Objective To establish a method for determination of pyriclobenzuron (PBU) residues in rice and paddy environments, and to determine the residual amounts and observe the degradation dynamics of PBU. Methods In July 2022, the paddies of Zhejiang Academy of Agricultural Sciences were selected as experimental fields, and were divided into the blank control group (no pesticide application), the 1-fold-concentration pesticide group (1 kg/667 m²), and the 5-fold-concentration pesticide group (5 kg/667 m²), with a 100 m² area in each group. At the early tillering stage of rice, 20% suspension of PBU sulfate was sprayed once in the 1-fold-concentration and 5-fold-concentration pesticide groups, and rice plants, paddy water and soil samples were collected 2 h, and 1, 2, 3, 5, 7, 11, 14, 21, 28, 35, 49 d and 63 d following spraying PBU, while rice straw, field soil, brown rice and rice husk samples were collected 98 d following spraying. PBU was extracted and purified in samples using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) pretreatment technique, and the PBU contents were determined in samples using ultrahigh performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The solvent standard working solution and matrix standard working solution were prepared. A linear regression equation was fitted between PBU concentration (x-axis) and peak area (y-axis), and the ratio of the slope (k) of the matrix standard curve to the slope (K) of the solvent standard curve was calculated to evaluate the matrix effect of PBU in samples. According to the Guidelines for Pesticide Residue Testing in Crops (NY/T 788—2018), the addition levels of PBU were set at 0.005, 0.050, 5.000, 1 000.000 mg/kg in rice plants, 0.005, 0.050, 2.000, 10.000 mg/kg in paddy water, 0.005, 0.050, 2.000 mg/kg in soil, and 0.005, 0.050, 5.000 mg/kg in brown rice and rice husks. The recovery and relative standard deviation (RSD) of PBU addition were calculated to evaluate the effectiveness of UPLC-MS/MS for determination of PBU contents. The first-order kinetic equation of PBU concentration was fitted in samples at different sampling time points to analyze the trends in PBU degradation in rice plants, paddy water, and soil, and the half-life of PBU was calculated in different samples. Results There was a good linear relationship between the mass concentration and peak area of PBU at concentrations of 0.000 1 to 0.020 0 mg/kg under solvent and matrix conditions (R² = 0.985 8 to 0.999 7, t = -0.47 to 1.62, all P values < 0.01). The matrix effects of PBU were 70.26%, 65.42% and 65.12% in rice plants, brown rice and rice husks, indicating a matrix-inhibitory effect, and the matrix effect was 87.06% in soils, indicating a weak matrix effect. The recovery of PBU addition was 77.61% to 100.12% in different samples, with RSD of 1.43% to 6.74%, and a limit of quantification (LOQ) of 0.005 mg/kg, and the addition recovery and RSD met the requirements of the Guidelines for Pesticide Residue Testing in Crops (NY/T 788—2018), validating the effectiveness of UPLC-MS/MS assay. Following spraying PBU at a dose of 1 kg/667 m², the half-life of PBU was 6.24 d in rice plants and 3.43 d in paddy water samples, respectively. The final residues of PBU were lower than the LOQ of 0.005 mg/kg in brown rice and rice husk samples 98 d following spraying PBU. Following spraying PBU at a dose of 5 kg/667 m², the half-life of PBU was 15.75 d in rice plants and 7.62 d in paddy water samples, respectively. The final residue of PBU was lower than the LOQ of 0.005 mg/kg in brown rice 98 d following spraying PBU, and the final residue of PBU was 0.049 mg/kg in rice husks. Conclusions A simple, and highly accurate and precise UPLC-MS/MS assay has been developed for determination of PBU residues in rice plants and paddy environments through extraction and purification of PBU from matrix samples using QuEChERS pretreatment. After spraying PBU in paddies, the concentration of PBU gradually decreases in rice plants and paddy water over time, and the final residual concentration is low.

OBJECTIVE: This study aimed to explore the association between body mass index (BMI) and mortality based on the 10-year population-based multicenter prospective study. METHODS: A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023. Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality. Stratified analyses were performed based on the individual characteristics of the participants. RESULTS: Overall, 19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died. The underweight (< 18.5 kg/m ²) presented an increase in all-cause mortality (adjusted hazards ratio [ aHR] = 2.00, 95% confidence interval [ CI]: 1.66-2.41), while overweight (≥ 24.0 to < 28.0 kg/m ²) and obesity (≥ 28.0 kg/m ²) presented a decrease with an aHR of 0.61 (95% CI: 0.52-0.73) and 0.51 (95% CI: 0.37-0.70), respectively. Overweight ( aHR = 0.76, 95% CI: 0.67-0.86) and mild obesity ( aHR = 0.72, 95% CI: 0.59-0.87) had a positive impact on mortality in people older than 60 years. All-cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m ² ( aHR = 0.95, 95% CI: 0.92-0.98) and increased slightly above that value, indicating a U-shaped association. The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses. CONCLUSION This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years. Therefore, it is essential to consider age differences when formulating health and weight management strategies.
Humans ; Body Mass Index ; China/epidemiology* ; Male ; Female ; Middle Aged ; Prospective Studies ; Rural Population/statistics & numerical data* ; Aged ; Follow-Up Studies ; Adult ; Mortality ; Cause of Death ; Obesity/mortality* ; Overweight/mortality*

Japanese spotted fever(JSF)is an infectious disease caused by Rickettsia japonica,with nonspecific clinical symptoms and a high risk of misdiagnosis.We reported a case of JSF,in which Rickettsia japonica was detected in blood cells by metagenomic next-generation sequencing.The patient recovered after treatment with doxycycline.This report provides a reference for the clinical diagnosis and treatment of JSF.
Humans ; High-Throughput Nucleotide Sequencing ; Metagenomics ; Rickettsia/isolation & purification* ; Spotted Fever Group Rickettsiosis/microbiology*

Three 2,3-diketoquinoxaline alkaloids were isolated from Heterosmilax yunnanensis Gagnep. Their structures were determined through 1D and 2D NMR, HR-ESI-MS, UV, and IR as 1-[5′-(3″-hydroxy-3″-methyl) glutaryl] ribityl-2,3-diketo-1,2,3,4-tetrahydro-6,7-dimethylquinoxaline (1), 1-[2′-(3″-hydroxy-3″-methyl) glutaryl]ribityl-2,3-diketo-1,2,3,4-tetrahydro-6,7-dimethylquinoxaline (2), and 1-ribityl-2,3-diketo-1,2,3,4-tetrahydro-6,7-dimethylquinoxaline (3). Compounds 1 and 2 are novel compounds, and 3 was isolated from H. yunnanensis for the first time. The hepatoprotective activity of these three compounds was evaluated, with compound 3 showing promising hepatoprotective activity.

Objective To investigate the feasibility of energy spectrum CT material separation technology for quantitative evaluation of nonalcoholic fatty liver patients,to compare the accuracy of this method with the conventional liver/spleen CT ratio for grading liver fat content.Methods Sixty patients diagnosed with nonalcoholic fatty liver and 20 healthy volunteers were chosen to undergo liver MR multi-echo(ME)Dixon and energy spectrum CT scans.The proton density fat fraction(PDFF),fat concentration(FC),and liver/spleen CT ratio were then measured for each participant.According to PDFF,nonalcoholic fatty liver patients were divided into mild fatty liver group,moderate fatty liver group,and severe fatty liver group.Results With the increase in PDFF,FC increased and the liver/spleen CT ratio decreased.The difference between FC groups in normal,mild,moderate and severe fatty liver groups was statistically significant(P<0.05),while the difference between the liver/spleen CT ratio of normal group and mild fatty liver group was not statistically significant(P>0.05).The receiver operating characteristic(ROC)curve analysis showed that when the critical value of FC was 351.19 mg/mL,the sensitivity,specificity and area under the curve for normal group and fatty liver group were 0.95,0.1 and 0.99,respectively.Conclusion The energy spectrum CT material separation technology has a good correlation between the fat content measured by the MR ME Dixon,which is superior to the fat content measured by the liver/spleen CT ratio.For patients with nonalcoholic fatty liver,FC in energy spectrum CT has high accuracy in differentiating normal and mild fatty liver.

Objective To investigate the characteristics of imaging signs of giant cell tumor(GCT)of the hand and foot bones.Methods The clinical,X-ray,CT and MRI images of 18 cases of GCT of hand and foot bones diagnosed by pathology were analyzed retrospectively.And compared with 54 cases of long bone GCT imaging manifestations.Results Among the 18 GCT cases of hand and foot bones,there were 8 cases of hand,10 cases of foot,including 12 cases of short tubular bone and 6 cases of tarsal bone.All lesions were dilatant osteolytic bone destruction involving the joint surface,in which the short tubular bone GCT showed central growth,the tumor occupied the entire wide diameter of the bone,the lesion range was long,consistent with the bone axis,easy to invade the surrounding soft tissue,sclerotic edge,bone ridge,lobed and periosteal reaction were rare,and prone to recurrence after surgery.The GCT of tarsal bone and short tubular bone showed eccentric growth,and there was statistical difference(P<0.05).The probability of pathological fracture in GCT of long bone was significantly greater than that of short tubular bone.There was no significant difference between the two groups in swelling growth,involvement of bone end and ethmoid sign of bone cortex.Conclusion Compared with long bone GCT,hand and foot bones are rare occurrence site of GCT,which is more aggressive than long bone GCT and prone to recurrence after surgery.Full attention should be paid to its imaging characteristics to provide more accurate image information for clinical treatment strategies.

BACKGROUND:Ischemic stroke is a highly prevalent disease associated with apoptosis.Neuronal death occurs after cerebral ischemia,including necrosis and apoptosis.The ischemic core region is dominated by necrosis,while delayed neuronal death in the penumbra is dominated by apoptosis.The penumbra has become a target for the treatment of ischemic stroke.This bibliometric analysis was used to identify the characteristics,hotspots,and frontiers of global scientific output related to apoptosis in ischemic stroke over the past 5 years. OBJECTIVE:To analyze the role of apoptosis and its mechanisms in the pathological process of ischemic stroke through a bibliometric approach. METHODS:A total of 927 relevant literature records from 2018 to 2022 were retrieved from Science Citation Index Expanded(SCI-Expanded)and Social Science Citation Index Expanded(SSCI-Expanded)of the Web of Science Core Collection.Research trends and hotspots of apoptosis in ischemic stroke were visualized using Citespace,VOSviewer and Bibliometrix. RESULTS AND CONCLUSION:From 2018 to 2020,the number of papers on the role of apoptosis in ischemic stroke showed an upward trend,but in 2020,the number of papers began to reduce.China had the largest number of publications,and the United States ranked the second.Capital Medical University and BRAIN RESEARCH BULLETIN were the institutions and journals with the most articles,respectively.In recent years,the two keywords"expression"and"oxidative stress"have appeared more frequently.The bibliometric study showed that in the past 5 years,most of the studies focused on basic research,in which research on the role of apoptosis in ischemic stroke has gradually decreased in the last 3 years,showing a downward trend.On the contrary,nerve regeneration has gradually become a research hotspot,especially the regulation of neurotrophic factors under the influence of different mechanisms,and the research on angiogenesis and glial cell repair is on the rise.At the same time,apoptosis in nerve regeneration is a potential point of discovery.