Association between urinary arsenic level and serum testosterone in Chinese men aged 18 to 79 years / 中华预防医学杂志

Objective: To investigate the association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years. Methods: A total of 5 048 male participants aged 18 to 79 years were recruited from the China National Human Biomonitoring (CNHBM) from 2017 to 2018. Questionnaires and physical examinations were used to collect information on demographic characteristics, lifestyle, food intake frequency and health status. Venous blood and urine samples were collected to detect the level of serum total testosterone, urinary arsenic and urinary creatinine. Participants were divided into three groups (low, middle, and high) based on the tertiles of creatinine-adjusted urinary arsenic concentration. Weighted multiple linear regression was fitted to analyze the association of urinary arsenic with serum total testosterone. Results: The weighted average age of 5 048 Chinese men was (46.72±0.40) years. Geometric mean concentration (95%CI) of urinary arsenic, creatinine-adjusted urinary arsenic and serum testosterone was 22.46 (20.08, 25.12) μg/L, 19.36 (16.92, 22.15) μg/g·Cr and 18.13 (17.42, 18.85) nmol/L, respectively. After controlling for covariates, compared with the low-level urinary arsenic group, the testosterone level of the participants in the middle-level group and the high-level group decreased gradually. The percentile ratio (95%CI) was -5.17% (-13.14%, 3.54%) and -10.33% (-15.68%, -4.63). The subgroup analysis showed that the association between the urinary arsenic level and testosterone level was more obvious in the group with BMI<24 kg/m2 group (Pinteraction=0.023). Conclusion: There is a negative association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years.

Association between urinary arsenic level and serum testosterone in Chinese men aged 18 to 79 years / 中华预防医学杂志

Objective: To investigate the association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years. Methods: A total of 5 048 male participants aged 18 to 79 years were recruited from the China National Human Biomonitoring (CNHBM) from 2017 to 2018. Questionnaires and physical examinations were used to collect information on demographic characteristics, lifestyle, food intake frequency and health status. Venous blood and urine samples were collected to detect the level of serum total testosterone, urine arsenic and urine creatinine. Participants were divided into three groups (low, middle, and high) based on the tertiles of creatinine-adjusted urine arsenic concentration. Weighted multiple linear regression was fitted to analyze the association of urinary arsenic with serum total testosterone. Results: The weighted average age of 5 048 Chinese men was (46.72±0.40) years. Geometric mean concentration (95%CI) of urinary arsenic, creatinine-adjusted urine arsenic and serum testosterone was 22.46 (20.08, 25.12) μg/L, 19.36 (16.92, 22.15) μg/L and 18.13 (17.42, 18.85) nmol/L, respectively. After controlling for covariates, compared with the low-level urinary arsenic group, the testosterone level of the participants in the middle-level group and the high-level group decreased gradually. The percentile ratio (95%CI) was -5.17% (-13.14%, 3.54%) and -10.33% (-15.68%, -4.63). The subgroup analysis showed that the association between the urinary arsenic level and testosterone level was more obvious in the group with BMI<24 kg/m2 group (Pinteraction<0.05). Conclusion: There is a negative association between the urinary arsenic level and serum total testosterone in Chinese men aged 18-79 years.

Study on formulation and revision of standard limits for inhalable particulate matter (PM10) and fine particulate matter (PM2.5) in "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

The pollution and health effects of indoor inhalable particulate matter (PM10) and fine particulate matter (PM2.5) are increasingly receiving public attention. The"Standards for indoor air quality (GB/T 18883-2022)"has revised the standard limit for PM10 and added the standard limit for PM2.5. This study analyzed and interpreted the relevant technical contents of the revision of the standard limits for two indicators, including the exposure status, health effects, and the basis for the determination of the limit value. It also proposed prospects for the future development and revision of standard limits for indoor particulate matters.

Study on formulation and revision of standard limits for inhalable particulate matter (PM10) and fine particulate matter (PM2.5) in "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

The pollution and health effects of indoor inhalable particulate matter (PM10) and fine particulate matter (PM2.5) are increasingly receiving public attention. The"Standards for indoor air quality (GB/T 18883-2022)"has revised the standard limit for PM10 and added the standard limit for PM2.5. This study analyzed and interpreted the relevant technical contents of the revision of the standard limits for two indicators, including the exposure status, health effects, and the basis for the determination of the limit value. It also proposed prospects for the future development and revision of standard limits for indoor particulate matters.

Association of blood lead and blood selenium with serum high-sensitivity C-reactive protein among Chinese adults aged 19 to 79 years / 中华流行病学杂志

Objective: To investigate the association of blood lead and blood selenium with serum high-sensitivity C-reactive protein (hs-CRP) among Chinese adults aged 19 to 79 years. Methods: The participants were enrolled from the first wave of China National Human Biomonitoring (CNHBM) conducted from 2017 to 2018. 10 153 participants aged 19 to 79 years were included in this study. Fasting blood samples were obtained from participants. Lead and selenium in whole blood and hs-CRP in serum were measured. Individuals with hs-CRP levels above 3.0 mg/L were defined as elevated hs-CRP. Generalized linear mixed models and restricted cubic spline models were used to analyze the association of blood lead and blood selenium with elevated hs-CRP. Logistic regression models were used to analyze the multiplicative scale and additive scale interaction between blood lead and blood selenium on elevated hs-CRP. Results: The age of participants was (48.91±15.38) years, of which 5 054 (61.47%) were male. 1 181 (11.29%) participants were defined as elevated hs-CRP. After multivariable adjustment, results from generalized linear models showed that compared with participants with the lowest quartile of blood lead, the OR (95%CI) of elevated hs-CRP for participants with the second, third, and highest quartiles were 1.14 (0.94-1.37), 1.25 (1.04-1.52) and 1.38 (1.13-1.68), respectively. When compared with participants with the lowest quartile of blood selenium, the OR (95%CI) of elevated hs-CRP for participants with the second, third and highest quartiles were 0.86 (0.72-1.04), 0.91 (0.76-1.11), and 0.75 (0.61-0.92), respectively. Results from the interaction analysis showed no significant interaction between lead and selenium on elevated hs-CRP. Conclusion: Blood concentration of lead was positively associated with elevated serum hs-CRP, and blood concentration of selenium was inversely related to elevated hs-CRP, while blood lead and selenium did not present interaction on elevated hs-CRP.

Correlation analysis of 3D-FLAIR MRI characteristics of the inner ear and vestibular function in the patients with vestibular neuritis / 中华耳鼻咽喉头颈外科杂志

Objective: The characteristics of 3D-FLAIR MRI images of the inner ear of patients with vestibular neuritis were preliminarily studied to explore the possible pathogenesis of vestibular neuritis, and the correlation analysis was conducted in combination with vestibular function to provide a basis for accurate diagnosis of vestibular neuritis. Methods: A total of 36 patients with vestibular neuritis (VN) from December 2019 to October 2020 were collected from the Vertigo Department of Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University. There were 36 cases (18 females, 18 males) with unilateral acute vestibular neuritis, 17 cases of left ear and 19 cases of right ear. According to the results of 3D-FLAIR MRI in the inner ears, the patients were divided into the enhanced group and the non-enhanced group (the health side served as the normal control group). The results of vestibular function examination in the two groups were compared. SPSS19.0 software was used for statistical processing to analyze the relationship between the vestibular function and the characteristics of 3D-FLAIR imaging in the inner ears. Results: Abnormal enhancement of 3D-FLAIR was found in 31 cases (86.1%) of the 36 cases, including 14 cases of both vestibular nerve and vestibular terminal organ enhancement, eight cases of superior vestibular nerve enhancement alone, seven cases of vestibular terminal organ enhancement alone, and two cases of cochlear enhancement alone. Observation of abnormal reinforcement of vestibular nerve showed: twenty-one cases of superior vestibular nerve reinforcement, one case of superior and inferior vestibular nerve reinforcement. No abnormalities were found in 3D-FLAIR of inner ear in 5 cases. According to the analysis of vestibular function results, there were 19 cases (52.8%) with total vestibular involvement, sixteen cases (44.4%) with superior vestibular involvement alone, and one case (2.8%) with inferior vestibular involvement alone. Comparison of vestibular function between the five cases (non-enhancement group) and the 31 cases (enhanced group) in the 3D-FLAIR group of the inner ears showed that the CP values of caloric tests in the enhanced group were higher (60.81±3.49 vs 34.12±7.37), with statistically significant difference (t=-2.898, P<0.01). Conclusion: In patients with vestibular neuritis, 3D-FLAIR MRI scan of the inner ear provides visual imaging evidence for clinical practice, considering that the lesion site of vestibular neuritis is not only in the vestibular nerve, but also in the vestibular end organ. Patients with 3D-FLAIR enhanced in the inner ear may have more significant vestibular function damage.

Effect of Hirsutine on Proliferation， Apoptosis， Metastasis， and Invasion of Human Cervical Cancer Ca Ski Cells / 中国实验方剂学杂志

ObjectiveTo investigate the effects of hirsutine on proliferation， apoptosis， metastasis， and invasion of human cervical cancer Ca Ski cells and its action mechanism. MethodThe cell proliferation was determined by cell counting kit-8 （CCK-8） assay and the cell apoptosis by Hoechst 33258 staining and flow cytometry. The mRNA expression levels of B cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and p53 were detected by real-time fluorescence quantitative polymerase chain reaction. The scratch test was conducted to detect the cell mobility， followed by the detection of cell invasion ability using a Transwell chamber. The contents of fibronectin （FN）， matrix metalloproteinase-2 （MMP-2）， and matrix metalloproteinase-9 （MMP-9） were measured by enzyme linked immunosorbent assay （ELISA）， and their protein expression levels were assayed by Western blot. ResultCompared with the control group， hirsutine inhibited the proliferation of Ca Ski cells in a dose- and time-dependent manner. The apoptosis rates and Bax and p53 mRNA expression levels in the 8.0， 16.0， 32.0 μmol·L-1 hirsutine groups rose （P<0.05， P<0.01）， while the Bcl-2 mRNA expression and phosphorylated Src （p-Src） and phosphorylated signal transducer and activator of transcription factor 3 （STAT3） protein expression declined （P<0.05， P<0.01）. Compared with the control group， the 1.0， 2.0， 4.0 μmol·L-1 hirsutine groups exhibited lowered cell mobility， number of transmembrane cells， FN， MMP-2 and MMP-9 contents， and hypoxia inducible factor-1α （HIF-1α）， Vimentin， and N-cadherin protein expression （P<0.05， P<0.01）， but elevated E-cadherin protein expression （P<0.01）. ConclusionHirsutine inhibits the proliferation， metastasis， and invasion of human cervical cancer Ca Ski cells and induces their apoptosis， which may be related to its regulation of Src/STAT3 and HIF-1α/epithelial mesenchymal transformation （EMT） signaling pathways.

Effect of melittin on programmed necrosis of human hepatocellular carcinoma cell line SMMC￣7721 / 解剖学报

Objective To investigate the lethal effect of melittin on human hepatocellular carcinoma cell line SMMC-7721 and its possible mechanism. Methods MTT assay was used to investigate the killing effect of different concentrations melittin on human hepatocellular carcinoma cells SMMC-7721. Meanwhile, the inhibitory effect of specific programmed necrosis inhibitors necrostain-1(Nec-1) on melittin killing SMMC-7721 cells was detected. Programmed cell necrosis observed by Hoechst 33342 and PI double staining. The necrotosis rate was detected by flow cytometry. Ultrastructural changes of cell was detected by transmission electron microscopy. The expression of receptor interacting protein 1(RIP1) was detected by Western blotting. Results Compared with the control group, the proliferation activity of SMMC-7721 cells was significantly decreased after treatment with different concentrations of melittin for 24 hours (P < 0. 05) . Cells stained in dark blue and red. Cell membrane integrity was destroyed, organelle swelling, organelle membrane was destroy, that demonstrates cell was necrosis. Westen blotting result showed an increased proportion of RIP1 expression in SMMC-7721 cells. Compared with the melittin group, cell proliferation activity was significantly increased, cell necrotosis rate was decreased, and intracellular RIP1 expression was down-regulated in the Nec-1 pretreatment group. Conclusion Melittin induces cell death in SMMC-7721 cells through the RIP1-mediated programmed necrosis pathway.

Identification of origin plant of Uygur medicine mulberry based on DNA barcode / 中国中药杂志

To provide molecular evidence for medical material identification, we analyzed the nucleotide sequence of ITS2, psbA-trnH gene in Morus genus plants and commercial products which were obtained from different places in Xinjiang. The sequence of ITS2 and psbA-trnH in fifty-one samples were amplified and sequenced, MEGA 6.0 was used to analyze the intra- and interspecific K-2P distances, neighbor-joining (NJ) tree was used to constructing clustering tree. ITS2 sequence analyzed results showed that there is no intra-specific variation among Morus alba, M. alba var. tatarica and M. nigra, but 13 variations sites were exist between M. alba and M. nigra and their inter-specific K-2P distances was 0.04, which indicated that there had significant variation in them. We didn't find informative variation sites between Morus genus plants and commercial products, and we also found that M. nigra can be distinguished from other two species by NJ Tree. PsbA-trnH analysis results showed there was only one variation site between M. alba and M. nigra, but insertion or deletion variation were remarkable evidence among M. alba, M. alba var. tatarica and M. Nigra. Inter-specific variation was accordance with intra-specific variation of commercial products. So ITS2 and psbA-trnH gene were important marker for M. alba, M. alba var. tatarica and M. nigra identification. This study provided important evidence for Uygur medicine identification and market supervision.

Dihydroartemisinin inhibits proliferation of pancreatic cancer JF-305 cells by regulating expression of apoptosis related proteins and production of reactive oxygen species / 中国中药杂志

To investigate the effect of dihydroartemisinin on apoptosis of human pancreatic cancer cell line JF-305 and the role of reactive oxygen species(ROS) in the apoptosis of JF-305 cells induced by dihydroartemisinin. MTT assays were used to detect effect of different concentrations of dihydroartemisinin on cells proliferation of JF-305 lines. Cell cycle was detected by flow cytometry, and the apoptotic morphology was observed by Hoechst 333258 fluorescence staining. Annexin V fluorescence staining was used to detect the apoptosis changes of JF-305 cells, while DCFH-DA was used to detect the changes of ROS during apoptosis process. Western blot was used to detect the protein expression changes of Bax, Bcl-2, Cleaved caspase-3, Cleaved caspase-9 and Cyto C. As compared with the control group, the JF-305 cells proliferation was inhibited significantly(P<0.05) after treatment with different concentrations of dihydroartemisimin for 48 h; cell cycle was blocked in the G2/M phase; apoptotic morphology of nuclear condensation, aggregation, and fragmentation was found, and the apoptosis ratio was increased(P<0.05). DCFH-DA detection showed that the cell ROS was increased significantly after dihydroartemisinin treatment(P<0.05). Western blot results showed that the expression of Bcl-2 protein was down-regulated; the expression of Bax protein was up-regulated; the ration of Bax/Bcl-2 was increased and the protein expression levels of Cleaved caspase-3, Cleaved caspase-9 and Cyto C were increased after dihydroartemisinin treatment. Therefore, dihydroartemisinin could induce apoptosis of JF-305 cells, and the possible mechanism may be related to the formation and increasing of ROS.

Effect of Qidan Granule on PMC Derived Peptide Content and Structure of Hippocampal CA1 Region in Microwave Radiated Rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the protection of high intensity microwave radiation on hypothalamo-pituitary-adrenal axis (HPAA) activity and hippocampal CA1 structure in rats and the protectiveeffect of Qindan Granule (QG) on radiation injured rats.</p><p><b>METHODS</b>Totally 48 Wistar rats were randomlydivided into 8 groups, i.e., the normal control group, post-radiation day 1, 7, and 10 groups, 7 and 10days prevention groups, day 7 and 10 treatment groups, 6 in each group. Rats in prevention groups wererespectively administered with QG liquid (1 mL/100 g, 4. 75 g crude drugs) for 7 days and 10 days bygastrogavage and then microwave radiation. Then preventive effect for radiation injury was statisticallycalculated with the normal control group and the post-radiation day 1 group. Rats in treatment groupswere firstly irradiated, and then administered with QG liquid (1 mL/100 g, 4.75 g crude drugs). Finally preventive effect for radiation injury was statistically calculated with the normal control group, post-radiation day 7 and 10 groups. Contents of corticotrophin releasing hormone (CRH), beta endorphin (beta-EP), adrenocorticotropic hormone (ACTH), and heat shock protein 70 (HSP70) were detected. Morphological changes and structure of hippocampal CA1 region were observed under light microscope.</p><p><b>RESULTS</b>Compared with the normal control group, contents of CRH and beta-EP significantly decreased in each radiation group. Serum contents of ACTH and beta-EP significantly increased in post-radiation day 1 and 7 groups (P < 0.05). Compared with radiation groups, beta-EP content in serum and pituitary significantly increased, and serum ACTH content significantly decreased in prevention groups (P < 0.05). Pituitary contents of CRH and beta-EP significantly increased in prevention groups. Serum contents of ACTH, beta-EP, and HSP70 were significantly lower in day 7 treatment group than post-radiation day 7 group (P < 0.05). Morphological results showed that pyramidal neurons in the hippocampal CA1 region arranged in disorder, with swollen cells, shrunken and condensed nucleus, dark dyeing cytoplasm, unclear structure. Vessels in partial regions were dilated with static blood; tissues were swollen and sparse. In prevention and treatment groups pathological damage of hippocampal CA1 region was obviously attenuated; neurons were arranged more regularly; swollen, pycnotic, or deleted neuron number were decreased; vascular dilatation and congestion was lessened.</p><p><b>CONCLUSION</b>QG could affect HPAA function and activity of high intensity microwave radiated rats, showing certain preventive and therapeutic effects of microwave radiated rats by adjusting synthesis and release of partial bioactive peptides and hormones in HPAA, improving pathological injury in hippocampal CA1 region.</p>

Analysis of porphyrin photosensitizers using HPLC method / 药学学报

Photodynamic therapy (PDT), because of its good targeting, minimal invasion, and safety, is becoming a very active area in cancer prevention and treatment, in which the photosensitizers have proved to be the core element for PDT. We developed a new HPLC method for analyzing porphyrin photosensitizers using Shiseido Capcell PAK C18 (150 mm x 4.6 mm, 5 µm) as the column at 30 °C, methanol-1% aqueous solution of acetic acid as the mobile phase in a flow rate of 1.0 mL · min(-1) in a gradient elution mode, and the detection wavelength at 380 nm. This method, showing good specificity, precision, accuracy and robusty via methodology validations, can be applied to the purity test and assay of porphyrin photosensitizers, and has played a key guide role in the R&D of the new porphyrin photosensitizer--sinoporphyrin sodium.

Visualization of endolymphatic hydrops in 3D-FLAIR MRI after intratympanic Gd-DTPA administration in Meniere's disease patients / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To study the feasibility of endolymphatic visualization and the diagnosis of Meniere's disease by applying intratympanic gadolinium administration through the tympanic membrance and three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI). To study the relationship between the endolymphatic hydrops visualized by MRI and audio-vestibular functional tests, such as pure tone audiometry (PTA), electrocochleography (EcoG), caloric test and vestibular evoked myogenic potential (VEMP).</p><p><b>METHODS</b>With a three Tesla magnetic resonance imaging (MRI) unit, 3D-FLAIR imaging was performed 24 hours after intratympanic gadolinium through the tympanic membrance in 32 patients with clinically diagnosed unilateral Meniere's Disease. We visualized the enhanced imaging of perilymphatic space in bilateral cochlea, vestibular and (or) canal, scoring scala tympani and scala vestibule of bilateral cochlear basal turn respectively and measuring the developing area of bilateral vestibule and the signal intensity ratio (SIR) between the vestibule and the brain stem subjectively. PTA, EcoG, caloric test and VEMP were performed. The relationship between the endolymphatic hydrops visualized by MRI and audio-vestibular functional tests were studied.</p><p><b>RESULTS</b>The gadolinium appeared in almost all parts of the perilymph in cochlea, vestibular and (or) canals in all 32 patients' inner ears, so the endolymphatic space was clearly shown on 3D-FLAIR imaging. The scala vestibuli score value between the affected side and the healthy side were statistically significant (Z = 4.309, P < 0.05) . The developing vestibular area between the affected side and the healthy side [(6.04 ± 2.89) mm(2), (8.28 ± 3.04)mm(2)] were statistically significant (t = 3.322, P < 0.05) . Abnormal vestibular evoked myogenic potentials were significantly correlated with the developing vestibular area of the affected side (F = 11.96, P < 0.05) . Abnormal electrocochleography were significantly correlated with scala vestibuli score value of cochlear basal turn in the affected side (Z = 3.17, P < 0.05) . No significant correlation was found between the scala vestibuli score value or the developing vestibular area and caloric test or PTA findings.</p><p><b>CONCLUSIONS</b>3D-FLAIR MRI with intratympanic gadolinium injection through the tympanic membrance can discriminate the border between the perilymph and the endolymph and show endolymphatic hydrops. This method may provide radiographic reference for the diagnosis of Meniere's disease. The results of VEMP and electrocochleography might have appropriate correlation with degree of vestibular and cochlear hydrops.</p>

High serum interleukin-6 level is associated with increased risk of delirium in elderly patients after noncardiac surgery: a prospective cohort study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The relationship between inflammation and delirium remains to be determined. The purposes of this study were to investigate the association between serum interleukin-6 levels and the occurrence of delirium in elderly patients after major noncardiac surgery.</p><p><b>METHODS</b>A total of 338 elderly patients (60 years of age and over) undergoing major noncardiac surgery were enrolled. Blood samples were obtained before anesthesia and in the first postoperative morning and serum interleukin-6 concentrations were measured. Delirium was assessed twice daily by the confusion assessment method for the Intensive Care Unit during the first three postoperative days. Survival analyses were performed to assess the relationship between the serum IL-6 level and the occurrence of postoperative delirium.</p><p><b>RESULTS</b>Postoperative delirium occurred in 14.8% (50 of 338) of patients. High serum interleukin-6 levelsafter surgery were significantly associated with increased risk of the occurrence of postoperative delirium (hazard ratio 1.514, 95% confidence interval 1.155-1.985, P = 0.003). Other independent predictors of delirium included increasing age, poor preoperative New York Heart Association classification, low preoperative Mini-Mental State Examination score, and high total postoperative Visual Analogue Scale pain score. Patients who developed delirium had a prolonged hospital stay after surgery.</p><p><b>CONCLUSIONS</b>Delirium is a frequent complication in elderly patients after noncardiac surgery. High serum interleukin-6 level after surgery is associated with increased risk of the occurrence of postoperative delirium.</p>

Effects of different sized titanium dioxide particles on reactive oxygen species in mice / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To observe the effects of different sized titanium dioxide on reactive oxygen species (ROS) levels.</p><p><b>METHODS</b>Forty-eight healthy mice were divided into 3 groups randomly: control group (distilled water), 50 nm TiO₂ (5 g/kg) group and 120 nm TiO₂ (5 g/kg) group. The mice were exposed to distilled water or TiO₂ by a syringe via gastrointestinal tract in a minute. One week later, the mice were sacrificed and the liver, kidney and brain (cortex, hippocampus) were collected. The contents of Ti in the above tissues of mice were measured by ICP-MS. The ROS levels in the tissues were measured by flow cytometry.</p><p><b>RESULTS</b>There was no significant difference in organ coefficient between two exposure groups and control group (P > 0.05). The Ti contents in liver, kidney, cortex and hippocampus of two exposure groups were higher than those of control group (P < 0.05); The Ti contents of above four tissues in 50 nm TiO₂ group were higher than those in 120 nm group (P < 0.05). The ROS levels in liver, kidney and cortex cells of two exposure groups (273.2 ± 32.5, 160.2 ± 28.5, 74.9 ± 8.9; 159.4 ± 15.9, 64.4 ± 7.5, 41.2 ± 5.6) significantly increased, as compared with control group (74.9 ± 6.4, 24.9 ± 2.8, 32.8 ± 3.1) (P < 0.05). The ROS levels in hippocampus cells in 50 nm TiO₂ group were significantly higher than those in control group (P < 0.05). The ROS levels of above four tissues in 50 nm group were significantly higher than those in 120 nm TiO₂ group (P < 0.05).</p><p><b>CONCLUSION</b>After mice were exposed to 50 nm and 120 nm TiO₂ particles via gastrointestinal tract, Ti could be distributed into the liver, kidney and the brain tissues in mice, resulting in the enhanced ROS levels in liver, kidney, cortex and hippocampus cells. Moreover, the ROS levels induced by 50 nm TiO₂ particles are significantly higher than those induced by 120 nm TiO₂ particles.</p>

Determination of tanshinone IIA in rat plasma and the pharmacokinetics by RP-HPLC method / 药学学报

<p><b>AIM</b>To develop a sensitive and rapid HPLC method for the determination of tanshinone IIA (TS) in rat plasma and to study its pharmacokinetics in rats.</p><p><b>METHODS</b>TS and 4-chlorodiphenyl (internal standard) were extracted from plasma with ethyl acetate. After liquid-liquid extraction, the sample was analyzed by HPLC with YMC C18 column (5 microns, 150 mm x 3.0 mm ID). The mobile phase consisted of acetontrile-water-acetic acid (74:26:1) at the flow rate of 0.3 mL.min-1, the UV detection wave length was 270 nm.</p><p><b>RESULTS</b>The calibration curve was linear (r = 0.9981) in the range from 0.05 to 6.40 mg.L-1. The lowest detectable concentration was 0.05 mg.L-1. The recoveries at the concentration of 0.05, 1.60 and 6.40 mg.L-1 were 98.9%, 102.1% and 100.4%, respectively. The inter- and intra-day RSDs were all less than 5%.</p><p><b>CONCLUSION</b>This method is proved to be rapid, precise and reliable enough to be applied to the pharmacokinetics studies of TS in rats after a single dose of 15 mg.kg-1 by oral administration.</p>