Objective:To develop a method of employing flow cytometry to directly detect the γ-H2AX expression levels in peripheral blood lymphocytes of mice through fixation and lysis and to evaluate the feasibility of applying this method to research on the radiation-related biological effects and the efficacy evaluation of radioprotective drugs.Methods:A total of 41 male C57BL/6J mice were used. First, 21 mice were randomly divided into 7 groups according to different radiation doses (0, 1, 2, 4, 6, 8, and 10 Gy) with 3 mice in each group. Blood samples were collected from the tail vein of mice at 1, 4, 8, and 24 h after irradiation and immediately fixed with formaldehyde. Red blood cells (RBC) were lysed with Triton X-100, and γ-H2AX was labeled with specific antibodies. DRAQ5 dye was used to further exclude debris and anucleate cells. The mean fluorescence intensity of γ-H2AX in lymphocyte populations was directly analyzed by flow cytometry through forward and side scatter, and dose-effect curves after irradiation were established. Then, the other 20 mice were divided into radiation alone groups and radiation combined with WR-2721 administration groups at 4 and 6 Gy, respectively, with 5 mice in each group. Blood samples were collected from the tail vein of mice at 1, 4, 8, and 24 h after irradiation to detect the average fluorescence intensity of γ-H2AX in lymphocytes, which was used to evaluate the degree of DNA damage in mice and the therapeutic effect of WR-2721.Results:The expression of γ-H2AX in peripheral blood lymphocytes of mice significantly increased with the increase of radiation doses, and reached a peak at 1-2 h and then decreased. The dose-effect relationship was significant ( R2 = 0.9914). At 24 h after 4 and 6 Gy irradiation, compared with the radiation alone groups, the average fluorescence intensity of γ-H2AX in the radiation combined with WR-2721 administration groups was lower (144.8 ± 8.0 and 109.5 ± 9.7, vs. 178.0 ± 18.5 and 136.6 ± 5.4), with statistically significant difference ( t = 3.78, 5.48, P < 0.05). The average fluorescence intensity of γ-H2AX at 24 h after irradiation was consistent with the lowest values of the three blood cell lines at 7 or 14 d after irradiation. Conclusions:The application of flow cytometry with a fixation/dissolution protocol to directly detect the mean fluorescence intensity of γ-H2AX in peripheral blood lymphocytes of mice has significant application value in radiation biology effect research, radiation protection drug screening, and efficacy evaluation.

The medicinal materials of Bawei Chenxiang Pills(BCPs) were extracted via three methods: reflux extraction by water, reflux extraction by 70% ethanol, and extraction by pure water following reflux extraction by 70% ethanol, yielding three extracts of ST, CT, and CST. The efficacy of ST(760 mg·kg~(-1)), CT(620 mg·kg~(-1)), and CST(1 040 mg·kg~(-1)) were evaluated by acute myocardial ischemia(AMI) and p-chlorophenylalanine(PCPA)-induced insomnia in mice, respectively. Western blot was further utilized to investigate their hypnosis mechanisms. The main chemical components of different extracts were identified by the UPLC-Q-Exactive-MS technique. The results showed that CT and CST significantly increased the ejection fraction(EF) and fractional shortening(FS) of myocardial infarction mice, reduced left ventricular internal dimension at end-diastole(LVIDd) and left ventricular internal dimension at end-systole(LVIDs). In contrast, ST did not exhibit significant effects on these parameters. In the insomnia model, CT significantly reduced sleep latency and prolonged sleep duration, whereas ST only prolonged sleep duration without shortening sleep latency. CST showed no significant effects on either sleep latency or sleep duration. Additionally, both CT and ST upregulated glutamic acid decarboxylase 67(GAD67) protein expression in brain tissue. A total of 15 main chemical components were identified from CT, including 2-(2-phenylethyl) chromone and 6-methoxy-2-(2-phenylethyl) chromone. Six chemical components including chebulidic acid were identified from ST. The results suggested that chromones and terpenes were potential anti-myocardial ischemia drugs of BCPs, and tannin and phenolic acids were potential hypnosis drugs. This study enriches the pharmacological and chemical research of BCPs, providing a basis and reference for their secondary development, quality standard improvement, and clinical application.
Animals ; Drugs, Chinese Herbal/isolation & purification* ; Mice ; Male ; Sleep Initiation and Maintenance Disorders/physiopathology* ; Humans ; Myocardial Infarction/drug therapy* ; Myocardial Ischemia/drug therapy*

OBJECTIVE: To investigate the effect of irradiation dose rate of ⁶⁰Co γ-ray on hematopoietic and immune cells in total body irradiation (TBI) mice. METHODS: After TBI with 8 Gy ⁶⁰Co γ-ray at three irradiation dose rates of 0.027, 0.256 and 0.597 Gy/min, the survival and change of body weight of C57BL/6J mice were observed within 30 days. The peripheral blood parameters were examined at each time point within 30 days post-irradiation. The hematopoietic stem/progenitor cell counts of mice were examined on the 10^th and 30^th day post-irradiation by flow cytometry, as well as the proportions of immune cells in peripheral blood, bone marrow and spleen of mice on the 30^th day post-irradiation. RESULTS: After TBI with 8 Gy ⁶⁰Co γ-ray, the 30-day survival rate of high dose-rate group was 0, which was significantly lower than 90% of medium dose-rate group and 100% of low dose-rate group (both P < 0.001). The peripheral blood parameters of all three groups showed a sharp decline → low value → gradually recovering trend. The count of white blood cell, neutrophil, lymphocyte, red blood cell, platelet and hemoglobin level in the high dose-rate and medium dose-rate groups were significantly lower than those in the low dose-rate group on day 7-18 post-irradiation (all P < 0.05), but there were no significant differences between the high dose-rate and medium dose-rate groups (P >0.05). On the 10^th day after irradiation, the proportion and number of bone marrow hematopoietic stem/progenitor cells (including LK, LSK, LT-HSC, ST-HSC, and MPP cells) in the low dose-rate and medium dose-rate groups were significantly decreased compared to those in the normal group (all P < 0.05), but there were no significant differences between the two groups (P >0.05). On the 30^th day after irradiation, LSK, LT-HSC, ST-HSC and MPP cells in the low dose-rate group recovered to normal levels, while those in the medium dose-rate group were still significantly lower than those in the low dose-rate group (all P < 0.001). The results of bone marrow and peripheral immune cell tests on the 30^th day after irradiation showed that the ratios of T and B lymphocytes in the low dose-rate and medium dose-rate groups were reduced compared to that in the normal group (both P < 0.05), while the ratio of neutrophils was increased (P < 0.01). The trend of changes in the spleen and peripheral blood was consistent. CONCLUSION The degree of hematopoietic and immune cell damage in mice after TBI with 8 Gy ⁶⁰Co γ-ray is related to the dose rate, and low dose-rate irradiation can reduce the damage in the animal model. Therefore, choosing the appropriate dose rate of irradiation is a key factor in establishing an objective and reliable experimental animal model of irradiation.
Animals ; Mice ; Whole-Body Irradiation ; Gamma Rays ; Mice, Inbred C57BL ; Hematopoietic Stem Cells/radiation effects* ; Cobalt Radioisotopes ; Dose-Response Relationship, Radiation ; Male

OBJECTIVE: This study aimed to reexplore minimum iodine excretion and to build a dietary iodine recommendation for Chinese adults using the obligatory iodine loss hypothesis. METHODS: Data from 171 Chinese adults (19-21 years old) were collected and analyzed based on three balance studies in Shenzhen, Yinchuan, and Changzhi. The single exponential equation was accordingly used to simulate the trajectory of 24 h urinary iodine excretion as the low iodine experimental diets offered (iodine intake: 11-26 μg/day) and to further deduce the dietary reference intakes (DRIs) for iodine, including estimated average requirement (EAR) and recommended nutrient intake (RNI). RESULTS: The minimum iodine excretion was estimated as 57, 58, and 51 μg/day in three balance studies, respectively. Moreover, it was further suggested as 57, 58, and 51 μg/day for iodine EAR, and 80, 81, and 71 μg/day for iodine RNI or expressed as 1.42, 1.41, and 1.20 μg/(day·kg) of body weight. CONCLUSION The iodine DRIs for Chinese adults were established based on the obligatory iodine loss hypothesis, which provides scientific support for the amendment of nutrient requirements.
Humans ; Iodine/administration & dosage* ; Male ; Female ; China ; Young Adult ; Diet ; Adult ; Nutritional Requirements ; East Asian People

Objective To investigate the regulatory effect and molecular mechanism of circ_0044556 on the malignant biological behavior of triple negative breast cancer(TNBC)cells by targeting the miR-338-3p/bromodomain-containing protein 4(BRD4)axis.Methods The TargetScan online website was used to predict the binding sites of circ_0044556 with miR-338-3p and miR-338-3p with BRD4.Dual-luciferase reporter gene assays were performed to determine the relationship among circ_0044556,miR-338-3p,and BRD4 in MDA-MB-231 cells.Quantitative real-time PCR(qRT-PCR)and Western blotting were employed to detect the expression of circ_0044556,miR-338-3p,and BRD4 protein in human TNBC cell line MDA-MB-231 and human normal breast epithelial cells MCF-10A.MDA-MB-231 cells were divided into NC group,si-NC group(transfected with si-NC),si-circ_0044556 group(transfected with si-circ_0044556),si-circ_0044556+inhibitor NC group(transfected with si-circ_0044556 and inhibitor NC),and si-circ_0044556+miR-338-3p inhibitor group(transfected with si-circ_0044556 andmiR-338-3p inhibitor).qRT-PCR was applied to detect the expression of circ_0044556 and miR-338-3p;Western blotting was used to detect the expression of BRD4,E-cadherin,N-cadherin and Vimentin;the CCK-8 assay was applied to detect cell proliferation;flow cytometry was applied to detect cell apoptosis;and Transwell assays were used to detect cell invasion and migration.Thirty nude mice were randomly divided into NC group(tail vein injection of normal saline),si-NC group(tail vein injection of LV-NC),si-circ_0044556 group(tail vein injection of LV-circ_0044556),si-circ_0044556+inhibitor NC group(tail vein injection of LV-circ_0044556 and antiagomir NC),and si-circ_0044556+miR-338-3p inhibitor group(tail vein injection of LV-circ_0044556 and antiagomir miR-338-3p),with 6 mice per group.A xenograft tumor model was constructed by subcutaneous injection of MDA-MB-231 cells into nude mice,and tumor volume and weight were measured.Results TargetScan prediction results showed that the downstream miRNA of circ_0044556 was miR-338-3p,and the downstream target gene of miR-338-3p might be BRD4.Compared with transfecting mimic NC,transfection with miR-338-3p mimic significantly reduced the luciferase activities of WT-circ_0044556(0.34±0.03 vs.1.00±0.15,P<0.05)and WT-BRD4(0.41±0.05 vs.1.05±0.13,P<0.05)in MDA-MB-231 cells.Compared with MCF-10A cells,the expression levels of circ_0044556 and BRD4 protein in MDA-MB-231 cells were significantly increased,while the expression level of miR-338-3p was significantly decreased(P<0.05).Compared with NC group and si-NC group,the expression levels of circ_0044556,the protein expression levels of BRD4,N-cadherin,and Vimentin,and the OD450 value in MDA-MB-231 cells of si-circ_0044556 group and si-circ_0044556+inhibitor NC group were significantly decreased(P<0.05),the number of migrated and invaded cells was significantly reduced(P<0.05),and the expression level of miR-338-3p,the protein expression level of E-cadherin,and the cell apoptosis rate in MDA-MB-231 cells were significantly increased(P<0.05);downregulation of miR-338-3p rescued the inhibitory effect of circ_0044556 knockdown on invasion,migration,and proliferation of MDA-MB-231 cells.Compared with NC group and si-NC group,the tumor volume and weight in si-circ_0044556 group and si-circ_0044556+inhibitor NC group were significantly decreased(P<0.05);compared with si-circ_0044556 group and si-circ_0044556+inhibitor NC group,the tumor volume and weight in si-circ_0044556+miR-338-3p inhibitor group were significantly increased(P<0.05).Conclusion circ_0044556 may promote the malignant biological behaviors of TNBC cells through the miR-338-3p/BRD4 axis.

Objective:To develop a method of employing flow cytometry to directly detect the γ-H2AX expression levels in peripheral blood lymphocytes of mice through fixation and lysis and to evaluate the feasibility of applying this method to research on the radiation-related biological effects and the efficacy evaluation of radioprotective drugs.Methods:A total of 41 male C57BL/6J mice were used. First, 21 mice were randomly divided into 7 groups according to different radiation doses (0, 1, 2, 4, 6, 8, and 10 Gy) with 3 mice in each group. Blood samples were collected from the tail vein of mice at 1, 4, 8, and 24 h after irradiation and immediately fixed with formaldehyde. Red blood cells (RBC) were lysed with Triton X-100, and γ-H2AX was labeled with specific antibodies. DRAQ5 dye was used to further exclude debris and anucleate cells. The mean fluorescence intensity of γ-H2AX in lymphocyte populations was directly analyzed by flow cytometry through forward and side scatter, and dose-effect curves after irradiation were established. Then, the other 20 mice were divided into radiation alone groups and radiation combined with WR-2721 administration groups at 4 and 6 Gy, respectively, with 5 mice in each group. Blood samples were collected from the tail vein of mice at 1, 4, 8, and 24 h after irradiation to detect the average fluorescence intensity of γ-H2AX in lymphocytes, which was used to evaluate the degree of DNA damage in mice and the therapeutic effect of WR-2721.Results:The expression of γ-H2AX in peripheral blood lymphocytes of mice significantly increased with the increase of radiation doses, and reached a peak at 1-2 h and then decreased. The dose-effect relationship was significant ( R2 = 0.9914). At 24 h after 4 and 6 Gy irradiation, compared with the radiation alone groups, the average fluorescence intensity of γ-H2AX in the radiation combined with WR-2721 administration groups was lower (144.8 ± 8.0 and 109.5 ± 9.7, vs. 178.0 ± 18.5 and 136.6 ± 5.4), with statistically significant difference ( t = 3.78, 5.48, P < 0.05). The average fluorescence intensity of γ-H2AX at 24 h after irradiation was consistent with the lowest values of the three blood cell lines at 7 or 14 d after irradiation. Conclusions:The application of flow cytometry with a fixation/dissolution protocol to directly detect the mean fluorescence intensity of γ-H2AX in peripheral blood lymphocytes of mice has significant application value in radiation biology effect research, radiation protection drug screening, and efficacy evaluation.

Objective:To analyze the activity of lithium chloride (LiCl) against influenza virus A (H3N2) in human non-small cell lung cancer cells (A549).Methods:Different concentrations of LiCl were incubated with A549 cells, and the cytopathic effect (CPE) was observed after 24 hours, and the effect of LiCl on cell activity was determined by CCK-8 method. After H3N2 (MOI=1) infected A549 cells, different concentrations of LiCl were added and incubated for 24 hours, and the viral load was measured by real time/reverse transcription quantitative polymerase chain reaction (RT-qPCR), and the CPE was observed, and the viral titer was determined. Different concentrations of LiCl were incubated with A549 at 37 ℃ and 5% CO 2 for 2 hours, virus was added and incubated for 24 hours, and the viral load was determined by RT-qPCR. LiCl, H3N2 and A549 were incubated at 4 ℃ for 1 hour, 35 ℃, 5% CO 2 for 24 hours, and viral load was determined by RT-qPCR. H3N2 and A549 were incubated at 4 ℃for 1 hour, then different concentrations of LiCl were added, incubated at 35 ℃ with 5% CO 2 for 24 hours, and the viral load was determined by RT-qPCR. After H3N2 infected A549 cells, different concentrations of LiCl were added and incubated for 24 hours, and the viral RNA load and viral titer of the supernatant and cells were measured, respectively, and then the corresponding ratios of the supernatant and the cells were calculated. After H3N2 (MOI=10) and BV (MOI=1) infected A549 cells, different concentrations of LiCl were added for 24 h, and the viral load was determined by RT-qPCR. Results:When the concentration of LiCl was<50 mmol/L, the cell viability of A549>90%. Different concentrations of LiCl could significantly reduce the viral load of H3N2 ( P<0.000 1), and the CPE of the LiCl treatment group was more dose-dependent than that of the control group. LiCl did not inhibit viral replication by affecting the cell itself; Different concentrations of LiCl significantly inhibited the entry of H3N2 into A549 ( P<0.000 1), and also had a certain inhibitory effect on the adsorption of A549 cells ( P<0.1). LiCl did not affect the assembly and release of H3N2 ( P>0.05), and it was also found that LiCl had a broad spectrum of antiviral effects against multiple influenza virus strains ( P<0.000 1). Conclusions:LiCl may exert antiviral effect by inhibiting the adsorption and entry of H3N2 into A549 cells and the replication of H3N2 in A549 cells, which provides a data reference for the prevention and treatment of viral infection by LiCl.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Objective:To explore the influence of environment temperature on the incidence of testicular torsion.Methods:We collected the clinical data on 172 cases of testicular torsion diagnosed in the Second Hospital of Hebei Medical University from De-cember 2013 to December 2020.According to the local environment temperature on the day of onset,we divided the patients into groups A(below 0℃),B(0-10℃),C(10-20℃)and D(above 20℃),and compared the incidence rates of testicular torsion among the four groups,followed by correlation analysis.Results:The incidence rate of testicular torsion was 12.8％(n=22)in group A,35.5％(n=61)in B,34.9％(n=60)in C and 16.9％(n=29)in D,the highest at 0-10℃ in group B,with sta-tistically significant difference among the four groups(x2=29.07,P＜0.001).Spearman correlation analysis indicated that the inci-dence of testicular torsion was negatively correlated with the environment temperature(r=-0.261,P＜0.01),with no statistically significant difference among different seasons(x2=5.349,P＞0.05),but higher in autumn and winter than in the other two sea-sons.Conclusion:The incidence of testicular torsion is negatively correlated with the environment temperature,elevated when the temperature decreases,but has no statistically significant difference among different seasons,though relatively higher in autumn and winter.

OBJECTIVE: To investigate whether Omicron BA.1 breakthrough infection after receiving the SARS-CoV-2 vaccine could create a strong immunity barrier. METHODS: Blood samples were collected at two different time points from 124 Omicron BA.1 breakthrough infected patients and 124 controls matched for age, gender, and vaccination profile. Live virus-neutralizing antibodies against five SARS-CoV-2 variants, including WT, Gamma, Beta, Delta, and Omicron BA.1, and T-lymphocyte lymphocyte counts in both groups were measured and statistically analyzed. RESULTS: The neutralizing antibody titers against five different variants of SARS-CoV-2 were significantly increased in the vaccinated population infected with the Omicron BA.1 variant at 3 months after infection, but mainly increased the antibody level against the WT strain, and the antibody against the Omicron strain was the lowest. The neutralizing antibody level decreased rapidly 6 months after infection. The T-lymphocyte cell counts of patients with mild and moderate disease recovered at 3 months and completely returned to the normal state at 6 months. CONCLUSION Omicron BA.1 breakthrough infection mainly evoked humoral immune memory in the original strain after vaccination and hardly produced neutralizing antibodies specific to Omicron BA.1. Neutralizing antibodies against the different strains declined rapidly and showed features similar to those of influenza. Thus, T-lymphocytes may play an important role in recovery.
Humans ; Antibodies, Neutralizing ; Prospective Studies ; SARS-CoV-2 ; Breakthrough Infections ; COVID-19 Vaccines ; COVID-19 ; T-Lymphocytes ; China/epidemiology* ; Antibodies, Viral