Objective:To develop a method for determining 14C in seafood using a tube combustion furnace (or oxygen bomb combustion devices) coupled with liquid scintillation counting (LSC), in order to accurately determine 14C in seafood. Methods:Four categories of seafood samples (i.e., fish, crustaceans, mollusks, and algae) were collected. They were then subjected to high-temperature oxidation using a tube combustion furnace or oxygen bomb combustion devices to isolate CO 2, followed by an analysis of the radioactivity concentration of 14C using LSC. The combustion conditions were optimized by investigating the heating nodes and rates in the oxidation combustion furnace, and the CO 2 collection conditions were optimized by placing a NaOH absorption solution in the oxygen bomb combustion devices. Additionally, the optimal measurement conditions were determined by comparing the effects of varying scintillation cocktails and the dark adaptation time of two preparation methods, i. e., the adsorption and suspension method. Results:When a tubular combustion furnace was used for oxidation and combustion, the optimal heating rate of the sample pyrolysis temperature zone was determined at 1.5℃/min. In this case, the combustion efficiency of various seafood could reach over 95%. When the oxygen bomb combustion devices were employed, placing NaOH solutions both inside and at the exhaust end increased absorption efficiency by 10% compared to the traditional practice of placing a NaOH solution only at the exhaust end. Samples prepared using the absorption method should be kept in the dark for at least 10 h before measurement using LSC, while samples prepared with the suspension methods should be kept for at least 20 h. The results obtained using two preprocessing devices and two sample preparation method were consistent, with a detection limit of 9.10 Bq/kg (dry samples). Compared to the suspension method (The relative standard deviation of the results obtained by two preprocessing devices were 9.00% and 8.27%), the absorption method (the corresponding relative standard deviation were 3.61% and 3.29%) exhibited higher precision in repeated measurements.Conclusions:The aforementioned pretreatment devices and sample preparation method are suitable for determining 14C in seafood.

Loss-of-function variants in CSDE1 have been strongly linked to neuropsychiatric disorders, yet the precise role of CSDE1 in neurogenesis remains elusive. In this study, we demonstrate that knockout of Csde1 during cortical development in mice results in impaired neural progenitor proliferation, leading to abnormal cortical lamination and embryonic lethality. Transcriptomic analysis revealed that Csde1 upregulates the transcription of genes involved in the cell cycle network. Applying a dual thymidine-labelling approach, we further revealed prolonged cell cycle durations of neuronal progenitors in Csde1-knockout mice, with a notable extension of the G1 phase. Intersection with CLIP-seq data demonstrated that Csde1 binds to the 3' untranslated region (UTR) of mRNA transcripts encoding cell cycle genes. Particularly, we uncovered that Csde1 directly binds to the 3' UTR of mRNA transcripts encoding Cdk6, a pivotal gene in regulating the transition from the G1 to S phases of the cell cycle, thereby maintaining its stability. Collectively, this study elucidates Csde1 as a novel regulator of Cdk6, sheds new light on its critical roles in orchestrating brain development, and underscores how mutations in Csde1 may contribute to the pathogenesis of neuropsychiatric disorders.
Animals ; Neurogenesis/genetics* ; Cell Cycle/genetics* ; Mice, Knockout ; Mice ; Neural Stem Cells/metabolism* ; DNA-Binding Proteins/metabolism* ; Cyclin-Dependent Kinase 6/genetics* ; Cell Proliferation ; 3' Untranslated Regions ; Cerebral Cortex/embryology* ; RNA-Binding Proteins ; Mice, Inbred C57BL

Objective To evaluate the environmental radioactive safety level in China, monitor the radioactivity of strontium-90 (⁹⁰Sr) in seafood from selected marine regions of China, and optimize the di-(2-ethylhexyl)phosphoric acid (HDEHP) extraction chromatography method for determining Sr-90 in seafood. Methods In 2023, seafoods of fish, shrimp, shellfish, and seaweed were collected from the Shandong Province (Bohai Sea and Yellow Sea) and Hainan Province (South China Sea). The levels of Sr in the samples were determined by inductively coupled plasma atomic emission spectrometer (ICP-AES). The ⁹⁰Sr separation were performed using HDEHP extraction chromatography, while the recovery of ⁹⁰Sr were determined by the gravitmetry with the assistant of ICP-AES. Results The content of strontium in seafoods varies greatly, and excessive strontium and calcium in seafood may lead to overestimated recovery due to insufficient leaching during chromatographic separation by HDEHP extraction. Therefore, the yttrium content in the eluent should be analyzed by ICP . The radioactivity of ⁹⁰Sr in seafood from the sea areas in Shandong Province was 0.22-1.85 Bq/kg (dry weight), and that of seafood from Hainan Province was 0.19-1.82 Bq/kg (dry weight). Conclusion For the analysis of shirmp and seaweed samples, the recovery rate of ⁹⁰Sr should be analyzed using both gravimetry and ICP-AES. There is no significant linear correlation between total Sr and ⁹⁰Sr in seafood. There is no significant difference in ⁹⁰Sr radioactivity between the seafood samples collected from Shandong and Hainan. The ⁹⁰Sr radioactivity levels of all 28 samples are below the limit specified in the Limited concentrations of radioactive materials in foods (GB 14882—1994) and are within the range of environmental background fluctuations.

Objective To organize a nationwide interlaboratory comparison for measurement of gross α and gross β radioactivity in water, and improve the laboratory analysis of gross α and gross β radioactivity in water. Methods A unified comparison protocol was developed by the organizers. The groundwater with high natural radioactivity was used as water sample and distributed randomly to the participating laboratories. The participating laboratories used routine analytical methods to measure the samples and provided information such as analytical results, original records, and test reports. The results were evaluated using z-score. Results A total of 76 laboratories participated in the comparison, all employing the evaporation concentration-α/β counting method. Among them, 69 laboratories achieved |z| ≤ 2 for both gross α and gross β radioactivity measurements, and 32 laboratories achieved |z| ≤ 0.50 for both gross α and gross β radioactivity measurements. There were 69 laboratories with qualified results and 30 laboratories with excellent results, yielding a qualified rate of 90.8% and an excellent rate of 39.5%. Seven laboratories showed unqualified results and the unqualified rate was 9.2%. Conclusion Most laboratories have the ability to analyze gross α and gross β radioactivity in water. The main reasons for the deviation in comparison results are calibration efficiency, errors in the total residue mass caused by improper water sample processing operations. By analyzing the main technical problems existed in unqualified laboratories, their ability for measurement of gross α and gross β radioactivity in water has been improved.

Objective To explore the application value of metagenomic next-generation sequen-cing(mNGS)technology in the diagnosis of spinal tuberculosis.Methods A total of 129 patients with suspected spinal tuberculosis admitted from January 2021 to January 2023 were selected as study subjects.Lesion tissue samples were collected intraoperatively and subjected to conventional microbio-logical testing(CMT),Mycobacterium tuberculosis DNA(MTB-DNA)amplification testing,and mNGS testing.The diagnostic efficacy of different testing methods was compared using results of com-prehensive clinical diagnosis as the gold standard.Results Among 129 patients,101(78.29％)were confirmed to have spinal tuberculosis,and 28(21.71％)had other spinal infections.Using clinical results as the diagnostic gold standard,the sensitivity of mNGS was 94.06％(95/101),and specificity was 89.29％(25/28);the sensitivity of MTB-DNA amplification was 90.10％(91/101),and specificity was 89.29％(25/28);the sensitivity of CMT was 86.14％(87/101),and specifici-ty was 85.71％(24/28).Compared with MTB-DNA amplification and CMT,mNGS showed the highest consistency with clinical results,and its consistency in detecting different lesion sites was also optimal,with statistically significant differences(P＜0.05).Conclusion mNGS testing has high diagnostic value for spinal tuberculosis and can provide a reference for clinical diagnosis,thereby guiding clinical decision-making.

Objective: To study the effect of metformin sensitizing pancreatic cancer cells with radiotherapy, with a focus on elucidating the underlying mechanisms of radiotherapy resistance. In particular, the role of the PERK/P-eIF2/ATF4 signaling pathway in mediating these effects was preliminarily explored. Methods : Pancreatic cancer cell lines(PANC-1 and PANC-2) were categorized into control, radiotherapy, and drug treatment groups. Following the respective treatments, cell proliferation inhibition was assessed using the CCK-8 assay, colony formation assays, and cell death staining. Senescence was quantified by β-galactosidase(SA-β-Gal) staining. The expression of cell cycle regulators(P21, P16, γ-H2AX), apoptosis markers(Bax, Bcl-2, Cleaved caspase-3), and pathway-related proteins(PERK, P-eIF2, ATF4) was evaluated by Western blot and immunofluorescence. To further investigate the role of the PERK/P-eIF2/ATF4 axis in metformin-mediated modulation of pancreatic cancer cell senescence and radiosensitization, selective inhibitors(GSK2606414) and agonists(MK-28) of PERK were employed. Results : Radiotherapy markedly upregulated senescence-associated markers(P21, P16, γ-H2AX, and β-galactosidase activity) in pancreatic cancer cells. Senescent cells exhibited enhanced proliferative activity and increased tumor volume both in vitro and in vivo. Metformin mitigated radiotherapy-induced senescence by reducing the expression of senescence markers and significantly suppressing the clonogenic and proliferative capacity of treated cells. Mechanistically, radiotherapy activated the PERK signaling pathway, leading to increased expression of PERK, P-eIF2, and ATF4, thereby driving cellular senescence. Pharmacological inhibition of PERK reduced β-galactosidase activity, while PERK activation further promoted the expression of senescence-associated proteins—an effect that was reversed by metformin. Conclusion Metformin inhibits the activation of the PERK/P-eIF2/ATF4 signaling pathway in pancreatic cancer cells following radiotherapy, thereby delaying cellular senescence and reducing the associated radiotherapy resistance of senescent cells. This modulation contributes to the sensitization of pancreatic cancer cells to radiotherapy.

OBJECTIVE: To apply optical genome mapping (OGM) technique for the analysis of genetic etiology in two rare families with complex chromosomal rearrangements (CCRs) and to provide precise reproductive guidance to them. METHODS: Two Chinese families diagnosed with chromosomal rearrangements by chromosomal microarray analysis (CMA) or whole-exome sequencing (WES) between June and December 2023 at the Affiliated Women and Children's Hospital of Ningbo University were selected as the study subjects. In both cases, unbalanced chromosomal translocations were suspected. Clinical data were collected, and peripheral blood from the couple, amniotic fluid sample and aborted fetal tissue was subjected to combined G-banding karyotyping and OGM for comprehensive genetic analysis. This study has been approved by the Medical Ethics Committee of the Hospital (Ethics No.: EC2023-094). RESULTS: In family 1, the fetus was signaled to have abnormal chromosome 7 by non-invasive prenatal testing (NIPT), prompting amniocentesis and CMA detection. In family 2, a pregnancy loss had occurred at 10 weeks' gestation, and trio-WES was carried out. Both fetuses were found to harbor copy number variations (CNVs) suggestive of unbalanced CCRs. Further analysis with OGM has revealed that, in family 1, an unbalanced rearrangement involving chromosomes 7, 8, and 10 was carried by the fetus and the pregnant woman, which has formed der(8) and der(10) derivative chromosomes. In family 2, a maternal CCR was found, which involved chromosomes 2 and 13 with seven breakpoints, resulting in unbalanced fetal CNVs. After genetic counseling, family 1 opted to continue with the pregnancy, considering the woman's normal appearance and inheritance of the rearrangement. For both families remained to have a risk for unbalanced rearrangements in subsequent pregnancies, preimplantation genetic testing (PGT) was recommended. CONCLUSION In both families, the OGM has precisely delineated the genetic basis of fetal CNVs and mapped the maternal CCR breakpoints, providing critical insights for genetic counseling and reproductive decision-making.
Adult ; Female ; Humans ; Male ; Pregnancy ; Chromosome Aberrations ; Chromosome Disorders/genetics* ; Chromosome Mapping/methods* ; Genetic Testing/methods* ; Pedigree ; Prenatal Diagnosis/methods* ; Translocation, Genetic

Aim To investigates whether sphingosine-1-phosphate(S1P)regulates the expression of mitochon-drial calcium uniporter(MCU)via the sphingosine-1-phosphate receptor/proline-rich tyrosine kinase 2(S1PR/Pyk2)sig-naling pathway,thereby reducing oxidative stress-induced mitochondrial damage and inhibiting mitochondria-related apopto-sis.Methods Human umbilical vein endothelial cells(HUVEC)were subjected to oxidative damage using hydrogen peroxide(H2O2)as a model.Different concentrations of S1P were applied to the oxidative damaged HUVEC.Addi-tionally,the S1PR1 agonist SEW2871,the S1PR1 inhibitor W146,and the Pyk2 inhibitor PF-562271 were used to explore the specific mechanism of S1P action.Results S1P treatment significantly alleviated oxidative damage in HUVEC and was accompanied by an increase in S1PR1 expression(P<0.05),while S1PR3 expression remained unchanged.Mean-while,the expression levels of Pyk2 and MCU decreased(P<0.05).SEW2871 further reduced mitochondrial damage,whereas W146 exacerbated it(P<0.05).Furthermore,the application of the Pyk2 inhibitor PF-562271 also reduced H2O2-induced mitochondrial damage(P<0.05),further confirming the role of Pyk2 in this process.Conclusion S1P reduces H2O2-induced mitochondrial damage and inhibits mitochondria-related apoptosis in HUVEC by suppressing Pyk2 expression via S1PR1.

Breast cancer is one of the most common malignant tumors among women worldwide, with an increasing incidence rate year by year, making it a significant public health concern. With the continuous advancement of tumor biology research, N 6-methyladenosine (m 6A) modification, as an important form of RNA modification, has attracted growing attention. The m 6A modification, the most prevalent RNA modification in eukaryotes, occurs in almost all types of RNA and plays a critical role in the occurrence, progression, and metastasis of breast cancer. It influences cell proliferation, apoptosis, and alterations in the tumor microenvironment, though the specific mechanisms underlying these effects require further in-depth investigation. Moreover, the specific patterns of m 6A modification demonstrate its potential as a novel biomarker for breast cancer, which could provide new directions for early diagnosis and prognosis evaluation.

OBJECTIVE: To evaluate the effect of biodegradable magnesium alloy materials in promoting tendon-bone healing during rotator cuff tear repair and to investigate their potential underlying biological mechanisms. METHODS: Forty-eight 8-week-old Sprague Dawley rats were taken and randomly divided into groups A, B, and C. Rotator cuff tear models were created and repaired using magnesium alloy sutures in group A and Vicryl Plus 4-0 absorbable sutures in group B, while only subcutaneous incisions and sutures were performed in group C. Organ samples of groups A and B were taken for HE staining at 1 and 2 weeks after operation to evaluate the safety of magnesium alloy, and specimens from the supraspinatus tendon and proximal humerus were harvested at 2, 4, 8, and 12 weeks after operation. The specimens were observed macroscopically at 4 and 12 weeks after operation. Biomechanical tests were performed at 4, 8, and 12 weeks to test the ultimate load and stiffness of the healing sites in groups A and B. At 2, 4, and 12 weeks, the specimens were subjected to the following tests: Micro-CT to evaluate the formation of bone tunnels in groups A and B, HE staining and Masson staining to observe the regeneration of fibrocartilage at the tendon-bone interface after decalcification and sectioning, and Goldner trichrome staining to evaluate the calcification. Immunohistochemical staining was performed to detect the expressions of angiogenic factors, including vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2), as well as osteogenic factors at the tendon-bone interface. Additionally, immunofluorescence staining was used to examine the expressions of Arginase 1 and Integrin beta-2 to assess M1 and M2 macrophage polarization at the tendon-bone interface. The role of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in tendon-bone healing was further analyzed using real-time fluorescence quantitative PCR. RESULTS: Analysis of visceral sections revealed that magnesium ions released during the degradation of magnesium alloys did not cause significant toxic effects on organs such as the heart, liver, spleen, lungs, and kidneys, indicating good biosafety. Histological analysis further demonstrated that fibrocartilage regeneration at the tendon-bone interface in group A occurred earlier, and the amount of fibrocartilage was significantly greater compared to group B, suggesting a positive effect of magnesium alloy material on tendon-bone interface repair. Additionally, Micro-CT analysis results revealed that bone tunnel formation occurred more rapidly in group A compared to group B, further supporting the beneficial effect of magnesium alloy on bone healing. Biomechanical testing showed that the ultimate load in group A was consistently higher than in group B, and the stiffness of group A was also greater than that of group B at 4 weeks, indicating stronger tissue-carrying capacity following tendon-bone interface repair and highlighting the potential of magnesium alloy in enhancing tendon-bone healing. Immunohistochemical staining results indicated that the expressions of VEGF and BMP-2 were significantly upregulated during the early stages of healing, suggesting that magnesium alloy effectively promoted angiogenesis and bone formation, thereby accelerating the tendon-bone healing process. Immunofluorescence staining further revealed that magnesium ions exerted significant anti-inflammatory effects by regulating macrophage polarization, promoting their shift toward the M2 phenotype. Real-time fluorescence quantitative PCR results demonstrated that magnesium ions could facilitate tendon-bone healing by modulating the PI3K/AKT signaling pathway. CONCLUSION Biodegradable magnesium alloy material accelerated fibrocartilage regeneration and calcification at the tendon-bone interface in rat rotator cuff tear repair by regulating the PI3K/AKT signaling pathway, thereby significantly enhancing tendon-bone healing.
Animals ; Rotator Cuff Injuries/metabolism* ; Rats, Sprague-Dawley ; Signal Transduction ; Wound Healing/drug effects* ; Alloys/pharmacology* ; Rats ; Proto-Oncogene Proteins c-akt/metabolism* ; Rotator Cuff/metabolism* ; Macrophages/metabolism* ; Magnesium/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Vascular Endothelial Growth Factor A/metabolism* ; Male ; Biocompatible Materials ; Bone Morphogenetic Protein 2/metabolism*