Research progress on the role of cytochrome P450 in plant sesquiterpene biosynthesis / 药学学报

Sesquiterpenes are natural terpenoids with 15 carbon atoms in the basic skeleton, which mainly exist in plant volatile oil and have important physiological and medicinal value. Cytochrome P450 (CYP450) is a kind of monooxygenase encoded by supergene family, which is one of the largest gene families in plants. It is involved in the synthesis and metabolism of terpenoids, alkaloids and other secondary metabolites. In the process of terpene biosynthesis, CYP450 participates in the post-modification stage of terpenes by introducing functional groups such as hydroxyl, carboxyl and carbonyl, which plays an important role in enriching the diversity of terpenes. The CYP450 enzymes involved in sesquiterpene synthesis and their substrate catalytic specificity mechanisms have been partially investigated. In this paper, the biosynthetic pathway of plant sesquiterpenes, the structure and classification of CYP450 enzymes were briefly introduced, and the CYP450 enzymes involved in sesquiterpene biosynthesis were summarized, in order to provide a reference for intensive study of the role of CYP450 enzymes in the synthesis of sesquiterpenoids.

Review of research on anti-gastric cancer mechanism of TCM compounds / 国际中医中药杂志

Traditional Chinese Medicine (TCM) shows unique advantages in the field of adjuvant treatment of gastric cancer. The main mechanism of TCM in improving gastric cancer includes regulating cell proliferation and apoptosis, reversing cell resistance, reducing the ability of invasion and metastasis and epithelial-mesenchymal transformation, regulating immune function, inhibiting neovascularization, regulating autophagy exosome, and ferroptosis.

Research progress on mechanism and medical prevention of refractive regression after laser myopia corneal refractive surgery / 国际眼科杂志(Guoji Yanke Zazhi)

Laser corneal refractive surgery is an effective way for the correction of myopia, and its long-term stability is a common concern of surgeons and patients. However, refractive regression is still one of the most common postoperative long-term complications, which has a great impact on postoperative refractive state and visual quality. Refractive regression may be related to many factors, such as the remodeling of corneal epithelium and stroma, and the imbalance between corneal biomechanics and intraocular pressure. Although enhancement surgery could be a useful way to correct refractive regression, there is a risk of corneal ectasia and other complications. Some intraocular pressure lowering medications can be used to rebuild the balance of intraocular pressure and corneal biomechanics, and to prevent postoperative refractive regression by affecting the thickness of corneal epithelium. To a certain extent, the type, the timing and the way of intraocular pressure lowering medications application may have an impact on the prevention and treatment effect of refractive regression.

Cloning and expression analysis of cytochrome P450 AsCYP71D1 from Aquilaria sinensis (Lour.) Gilg / 药学学报

Cytochrome P450 (CYP450) is a kind of superfamily oxidase containing heme, which is distributed in various aerobic organisms. They are widely involved in the biosynthesis of terpenoids, alkaloids, flavonoids, fatty acids, etc. In this study, the full-length cDNA sequence of a P450 was cloned by reverse transcription-PCR (RT-PCR) and rapid amplification of cDNA ends (RACE) technology, with the specific primers that designed according to the sequence of a transcript annotated as P450 from the Aquilaria sinensis (Lour.) Gilg transcriptome database. The tissue expression and subcellular localization were also studied. The full-length cDNA of the cloned P450 gene is 1 920 bp, with 88 bp 5′-untranslated region (UTR), 344 bp 3′-UTR and a 21 bp polyA tail, and 1 488 bp open reading frame (ORF), encoding 495 amino acids. Sequence alignment revealed that the protein belonged to CYP71D family of cytochrome P450 family, and named AsCYP71D1. Tissue expression analysis indicated that AsCYP71D1 was mainly expressed in stem. Further subcellular localization of onion epidermis showed that AsCYP71D1 was expressed in cytoplasm, nucleus and cell membrane. This study will provide a foundation for further research on its function in agarwood sesquiterpene biosynthesis.

Correlation analysis of smell and taste loss with COVID-19 outbreak trend based on big data of internet / 中华耳鼻咽喉头颈外科杂志

Objective: To analyze the correlation between loss of smell/taste and the number of real confirmed cases of coronavirus disease 2019 (COVID-19) worldwide based on Google Trends data, and to explore the guiding role of smell/taste loss for the COVID-19 prevention and control. Methods: "Loss of smell" and "loss of taste" related keywords were searched in the Google Trends platform, the data were obtained from Jan. 1 2019 to Jul. 11 2021. The daily and newly confirmed COVID-19 case number were collected from World Health Organization (WHO) since Dec. 30 2019. All data were statistically analyzed by SPSS 23.0 software. The correlation was finally tested by Spearman correlation analysis. Results: A total of data from 80 weeks were collected. The retrospective analysis was performed on the new trend of COVID-19 confirmed cases in a total of 186 292 441 cases worldwide. Since the epidemic of COVID-19 was recorded on the WHO website, the relative searches related to loss of smell/taste in the Google Trends platform had been increasing globally. The global relative search volumes of "loss of smell" and "loss of taste" on Google Trends was 10.23±2.58 and 16.33±2.47 before the record of epidemic while 80.25±39.81 and 80.45±40.04 after (t value was 8.67, 14.43, respectively, both P<0.001). In the United States and India, the relative searches for "loss of smell" and "loss of taste" after the record of epidemic were also much higher than before (all P<0.001). The correlation coefficients between the trend of weekly new COVID-19 cases and the Google Trends of "loss of smell" in the global, United States, and India was 0.53, 0.76, and 0.82 respectively (all P<0.001), the correlation coefficients with Google Trends of "loss of taste" was 0.54, 0.78, and 0.82 respectively (all P<0.001). The lowest and highest point of loss of smell/taste search curves of Google Trends in different periods appeared 7 to 14 days earlier than that of the weekly newly COVID-19 confirmed cases curves, respectively. Conclusions: There is a significant positive correlation between the number of newly confirmed cases of COVID-19 worldwide and the amount of keywords, such as "loss of smell" and "loss of taste", retrieved in Google Trends. The trend of big data based on Google Trends might predict the outbreak trend of COVID-19 in advance.

Exploration and practice on risk management of scientific research project in hospital / 中华医学科研管理杂志

Objective:By sorting out the occurrence of the risk outcomes of scientific research project in the hospital, conducting root-cause analysis, the risk management theory, process and methodologies are introduced into the management system of hospital scientific research projects to reduce the occurrence of risk outcome of scientific research projects.Methods:Through literature review and the reflection of daily scientific research management practice, the risk characteristics of clinical scientific research projects were systematically summarized, comparative analysis were conducted to explore the effectiveness before and after the introduction of risk management, and the practical experiences of scientific research project risk management were summarized.Results:There are mainly six types of internal and external risks in hospital scientific research projects, which lead to project termination, project modifications, project delays, assessment index adjustments, budget adjustments and other risk issues. By establishing scientific research project risk management environment, standardizing risk management procedures, as well as establishing risk-monitoring and early warning information system, the introduction of risk management system enables more effective control of scientific research project risks in hospitals.Conclusions:The application of risk management in the management of scientific research projects in hospitals has showed positive impact. The risk management of scientific research projects in hospitals has certain practical value and feasibility. The exploration of risk management theories and methods should be continued to promote the high-quality development of hospital scientific research project management.

Preliminary study on the collaborative development of drug clinical trial institutions and Contract Research Organizations from the perspective of "government-application-industry-academia-research" / 中华医学科研管理杂志

Objective:To explore the collaborative development of drug clinical trial institutions and Contract Research Organizations from the perspective of " government-application-industry-academia-research" , and facilitate faster and better conducting of clinical trials.Methods:Based the combination of literature review and the working practice in drug clinical trial management, problems existed during the implementation of clinical trials were summarized, and then the collaborative development of drug clinical trial institutions and Contract Research Organizations were discussed from the perspective of " government-application-industry-academia-research" partnership.Results:Problems identified during the implementation of clinical trials including uneven capacity of CROs, lack of effective supervision department and insufficient cooperation with clinical trial institutions, which resulted difficulties in sharing clinical trial resources and also negatively impacted the quality of clinical trials. Some proposals were offered in this article, including making good use of the " visible hand" of the government to strengthen the supervision of CROs, accelerating the construction of innovation alliance between clinical trial institutions and CROs, establishing the incentive mechanism of collaborative development and the talent team construction, strengthening the personnel professional training.Conclusions:The application of " government-application-industry-academia-research" model in clinical trials would promote the collaboration between drug clinical trial institutions and Contract Research Organizations, which play important roles in the development of clinical trials.

Application and practice of risk assessment in clinical research project approval / 中华医学科研管理杂志

Objective:Through the analysis of the risk factors of clinical scientific research project, risk assessment theory was brought in to develop risk assessment procedures, at the same time, to explore possible applications of risk assessment theories and methodologies in clinical scientific research projects, which might empower the research project administration.Methods:Through literature review and the author's scientific research management daily practice, the characteristics of risks involved in clinical scientific research projects were systematically summarized, relevant standards and models were used for reference to develop relevant working procedures, fatherly, methodologies of project risk assessment were discussed.Results:There are risks at different stages of scientific research project that including compliance, safety, research topic selection, research design, executive ability and risk-control. A proposal regarding to the implementation of project risk assessment covers three main steps which including preliminary preparation, implementation of risk assessment (risk identification, risk analysis and risk assessment) and risk-response proposal.Conclusions:The risk assessment of clinical scientific research projects is crucial. It is necessary to promote the development of risk assessment and improve the capacity building by improving awareness, establishing system, clarifying structure and improving technology.

A new isobenzofuranone derivative from Chaenomeles sinensis and its antibacterial activity / 中国中药杂志

A new isobenzofuranone derivative was isolated from Chaenomeles sinensis by using various chromatographic techniques,including silica gel,Sephadex LH-20,MCI-gel resin and RP-HPLC. This compound was determined as 2,2-dimethyl-5-( 2-oxopropyl)-2 H-furo[3,4-h]chromen-7( 9 H)-one( 1) by NMR,MS,IR and UV spectra,and was also evaluated for its antibacterial activity. The results showed that it showed prominent antibacterial activity with MIC90 value of( 53. 7±4. 5) mg·L-1 for methicillin resistant Staphylococcus aureus( MRSA) strain. This value is close to that of levofloxacin [with MIC90 value( 50. 2± 4. 2) mg·L-1].

Replication and Pathology of Duck Influenza Virus Subtype H9N2 in Chukar / 生物医学与环境科学（英文）

To investigate the susceptibility of Chukars to duck avian influenza virus H9N2 and explore their role in interspecies transmission of influenza viruses. Chukars were inoculated with duck avian influenza viruses H9N2. The present study demonstrated that inflammatory lesions and virus antigen were present in the trachea, bronchus, and parabronchus, and the viruses could be isolated from throat swabs and lung tissue homogenate supernatants. At 14 d post virus inoculation, anti-H9 influenza virus antibody in the serum was detected. The results indicated that Chukars are susceptible to duck avian influenza virus and serve as an intermediate host, thereby facilitating viral gene evolution and supporting the need for continued surveillance of epidemiology and evolution of the influenza virus in Chukars.

Chemical constituents from roots of Veratrilla baillonii / 中草药

Objective To study the chemical constituents from the roots of Veratrilla baillonii. Methods Compounds were purified by normal and reversed column chromatographic techniques, and isolated by high performance liquid chromatography. Their structures were identified on the basis of spectral data including MS and NMR. Results Twenty-four compounds (including 10 xanthone glycosides, 8 xanthones, and 6 iridoids) were isolated from the ethyl acetate extracts of the roots of V. baillonii. They were identified as 1-hydroxy-2,3,4-trimethoxyxanthone-7-O-β-D-glucopyranoside (1), tripteroside (2), 1-hydroxy-2,7-dimethoxyxanthone-3-O-β-D- glucopyranoside (3), 1-hydroxy-3,4-dimethoxyxanthone-7-O-β-D-glucopyranoside (4), secamonoide B (5), tetrasweroside A (6), veratriloside B (7), 2,3,4,5-tetramethoxyxanthone-1-O-β-D-glucopyranoxyl-(1→6)-β-D-glucopyranoside (8), 2,3,4,7-tetra- methoxyxanthone-1-O-β-D-xylopyranoxyl-(1→6)-β-D-glucopyranoside (9), 2,3,5-trimethoxy-xanthone-1-O-β-D-xylopyranoxyl- (1→6)-β-D-glucopyranoside (10), 1,3-dihydroxy-4,7-dimethoxyxanthone (11), 1,7-dihydroxy-2,3,4-trimethoxyxanthone (12), 1,7- dihydroxy-3,4-dimethoxyxanthone (13), 1,7-dihydroxy-3-methoxyxanthone (14), 1-hydroxy-2,3,4,5-tetramethoxyxanthone (15), 1-hydroxy-2,3,4,7-tetramethoxyxanthone (16), 1-hydroxy-2,3,5-trimethoxyxanthone (17), 1-hydroxy-2,3,7-trimethoxyxanthone (18), sweroside (19), gentiopicrin (20), swertiamarin (21), deacetylcentapicrin (22), amaronitidin (23), and amarogentin (24). Conclusion Compound 1 is a new compound named 2-methoveratriloside, and compounds 2, 3, 5, 6, 8, 10-12, 14, and 22-24 are isolated from the Veratrilla genus for the first time.

Study on the corrlation between workplace violence and empathy fatigue of nurses in tumor hospital / 中国实用护理杂志

Objective To investigate the workplace violence and empathy fatigue of nurses in tumor hospitals, and analyze the factors that affect the empathy fatigue of nurses in tumor hospitals, so as to provide references for nurses to prevent job burnout and quit their jobs. Methods Using the method of convenient sampling, 865 nursing staff in Cancer Hospital Affiliated to Harbin Medical University were selected as the research subjects. The general data questionnaire, the workplace violence measurement frequency scale and the empathy fatigue scale were used to investigate. Results Tumor hospital nurses workplace violence zero frequency in 261 cases, accounted for 30.17％, the frequency of 336 cases, accounted for 38.84％, 245 cases of intermediate frequency accounted for 28.32％, high frequency of 23 cases accounted for 2.66％; the feeling of fatigue and mild in 171 cases, accounted for 19.77％, 339 cases of moderate and severe in 355 cases, accounted for 39.19％, and 41.04％respectively;negative correlation workplace violence and empathy fatigue compassion satisfaction score (r=-0.164, P<0.01), and occupation burnout, secondary traumatic stress scores were positively correlated (r= 0.149, 0.196, P<0.01); nurse education and workplace violence is compassion satisfaction of the main influence factors(t = 8.284,-4.664, P<0.01); workplace violence, working age and age is the main influencing factors of occupation burnout(t=8.905, 4.114, 2.986, P<0.01);workplace violence (department of radiology), and education is the main influence factors of secondary traumatic stress(t=8.242,-5.822,-3.644,P<0.01). Conclusions The incidence of workplace violence is highamong nurses in tumor hospitals. The empathy fatigue of nurses in the tumor hospitals is more serious. It is necessary for nursing managers to give comprehensive intervention strategies, reduce the incidence of workplace violence and improve the empathy fatigue of nurses.

Clinical value and nursing intervention of prone position ventilation in treating patients / 重庆医学

Objective To investigate the effect of position ventilation(PPV) on oxygenation,the airway sputum drainage and hemodynamic of acute respiratory distress comprehensive syndrome(ARDS).Methods From June 2015 to April 2016,13 cases with moderate or severe ARDS were researched.The changes of PaO2,PaCO2,SpO2,PaO2/FiO2 and airway sputum drainage were observed as well as HR,MAP,CVP,CO,CI,SVV,etc.Results Totally 56 PPV were taken.Compared with pre-treatment of PPV,the number of PaO2 and PaO2/FiO2 increased from (74.7±13.18) mm Hg and 168.65±22.12 to (92.13±17.82) mm Hg and 208.80±24.04(P0.05).Conclusion PPV can effectively improve oxygenation in patients with ARDS and promote airway sputum drainage,and hemodynamic effects are not obvious.However,nursing intervention still should be strengthened.

Role of Mitogen-activated Protein Kinase Pathways in Expression of Aquaporin-4 in Astrocytes after Oxygen-glucose Deprivation in Rats / 中国康复理论与实践

@#Objective To investigate whether mitogen-activated protein kinases(MAPKs),which were involved in changes in osmolali-ty,might mediate aquaporin-4(AQP4)expression in astrocytes after oxygen-glucose deprivation(OGD)in rats.Methods Astrocytes were obtained from new born Sprague-Dawley rats.The P2cells were divided into control group,OGD group and inhibitors of U0126,SB203580 and SP600125 groups. The latter groups underwent OGD for five hours and reoxygenated, the inhibitors of U0126, SB203580 and SP600125(1 μmol/L and 10 μmol/L,respectively)groups,named U1,U10,SB1,SB10,SP1 and SP10 groups,respectively,were cultured with the inhibitors for twelve hours.The volume of cells in OGD group was measured half,one,one and half,two,three,four,eight and twelve hours after reoxygenation,and the expression of AQP4 was detected half,one,one and half,eight and twelve hours after reoxygen-ation with Western blotting.The expression of AQP4,and phosphorylation of extracellular regulated protein kinases(p-ERK),c-Jun N-termi-nal kinase(p-JNK)and p38 MAPK(p-p38 MAPK)was detected 24 hours after reoxygenation in all the groups,while the activity of lactate dehydrogenase(LDH)was measured.Results The volume of cells increased in OGD group one and half,two,three and four hours after re-oxygenation compared with those in the control group(P<0.001),and the expression of AQP4 also increased in OGD group after reoxygen-ation(P<0.001),especially 1.5 hours of reoxygenation.The expression of AQP4,p-ERK,p-JNK and p-p38 MAPK increased in OGD group after five hours of OGD compared with those in the control group(P<0.001),and the expression of p-ERK,p-JNK and p-p38 MAPK de-creased in the inhibitors groups compared with those in OGD group(P<0.001),and the expression of AQP4 decreased in SB10 group(P<0.001).The activity of LDH was less in all the inhibitors groups except SP1 and SB1 groups than in OGD group(P<0.01),and was the least in SB10 group (P<0.001). Conclusion MAPKs signal pathway, especially p38 MAPK, may promote AQP4 expression in astrocytes after OGD in rat,and play a role in cells death.

Study on the construction of training evaluation system of critical care nurses in Chongqing / 中华医学教育探索杂志

Objective To Establish an evaluation index system of critical care nurses training in Chongqing. Methods A panel of experts was formed with 20 experts from related fields. By the use of Del-phi method, we designed a questionnaire survey and took two rounds of expert consultation and revision, screening the intensive care nurse training evaluation index. SPSS 17.0 statistical software was used to assess the experts involved in the study and to determine the weight of indicators at all levels. Results In the course of the investigation, the experts participating in the initiative was very high, and the authority coeffi-cient (Cr) was 0.896. The training evaluation system of critical care nurses in Chongqing was initially iden-tified, including 3 first-level indicators, 7 second-level indicators 7, 21 third-level indicators. Conclusion The preliminary construction of critical care nurse training evaluation system in Chongqing can promote the ICU specialist nurse training effect and guarantee the training quality, and at the same time it provides some reference for the training and evaluation of the health administrative department.

The observation on the effect of recombinant human interleukin-11 inhalation for preventing and curing radioactive laryngitis / 中国实用护理杂志

Objective To conduct prospective randomized controlled clinical observation on patients with nasopharyngeal carcinoma under chemotherapy and radiotherapy using inhaling therapy with recombinant human interleukin 11,and the preventing and curing effect of recombinant human interleukin 11 on radiation-induced pharyngitis is evaluated.Methods 161 cases of newly diagnosed patients with head and neck cancer were selected under the principle of informed consent and these 161 cases were divided into the observation group (87 cases) and the control group (74 cases) based on randomization principle.In the observation group,when the dose reached 20Gy,then recombinant human interleukin-11 inhaling therapy was applied `ll the end of radiotherapy,for the control group,conventional treatment was applied in the event of radioactive throat.RTOG criteria were used during the observation in patients with the occurrence and treatment of radioactive pharyngitis.Results When compared with the control group,the average time for radioactivity to appear was prolonged,the severity decreased and the healing time was shortened in the observation group,those data were statistically significant.Conclusions Recombinant human interleukin-11 inhaling therapy can prevent and cure inhalation of radioactive pharyngitis and this therapy is better than conventional treatment.It's worthy of further study and clinical application.

Precise minimally invasive surgery of lower lumbar spine / 浙江大学学报·医学版

The fast development of minimally invasive spine surgery in recent years is based on the advance of endoscopic microsurgery techniques, computer science and medical imaging, as well as the growing concerning of medical humanities. The concept of minimally invasive and precise targeting therapy has been penetrating into various areas of surgery, and minimal tissue damage and fewer complications are the new directions of minimally invasive spine surgery. In this article we review some advances in precise spinal surgery including percutaneous lumbar discectomy, microendoscopic discectomy, computer-assisted orthopedic surgery and robot surgery.

Distribution characteristics of cancerous foci in the prostate among patients undergoing single positive core biopsy / 中华男科学杂志

<p><b>OBJECTIVE</b>To determine the distribution characteristics of cancerous foci in the prostate by retrospective analysis on the radical prostatectomy (RP) samples from patients with prostate cancer diagnosed by single positive core biopsy and treated by RP.</p><p><b>METHODS</b>Thirty-seven patients with prostate cancer diagnosed by ultrasound-guided biopsy and single positive core biopsy underwent RP. We reviewed the pre- and post-operative data of the patients, compared the results of biopsies and pathological examination of the RP samples, and analyzed the factors that led to the underestimation of the overall prostate cancer risks.</p><p><b>RESULTS</b>Post-operative pathological results showed multifocal distribution of the tumors in 70% of the patients (26/37) and obviously increased Gleason score (7-9) in 56% (21/37). The clinical stages of the tumors had been significantly underestimated preoperatively. The underestimation of their clinical stages might be due to a larger proportion of cancer tissues in a single positive core biopsy, and that of the overall cancer risks attributed to PSAD > 0.2 microg/L. Larger prostate volume (> or = 40 ml) increased the possibility of multifocal distribution.</p><p><b>CONCLUSION</b>The risk of prostate cancer diagnosed by single positive core biopsy might be underestimated, and the cancerous foci were characterized by multifocal distribution in the prostate.</p>

Value of BI-RADS ultrasonic scores of direct and indirect ultrasonographic signs in diagnosis of solid breast lesions / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the value of BI-RADS ultrasonic scores of direct and indirect ultrasonographic signs in diagnosis of solid breast lesions.</p><p><b>METHODS</b>Reference to the standard BI-RADS score, ultrasonic scores of direct and indirect ultrasonographic signs of 132 solid breast lesions were assigned, and were compared with pathological results.</p><p><b>RESULTS</b>By the direct signs of breast lesions (aspect ratio, shape, border, internal echo, posterior echo, flow grade, sand-like calcification) and indirect signs (changes in local skin thickness, Cooper ligament changes, axillary lymph nodes, depth of reinforcement membrane changes, mass changes in the surrounding burr), the integral from the total scores in benign and malignant breast masses showed a statistically significant difference. The total score of malignant lesions (8.94 ± 2.85) was significantly higher than that of benign tumors (3.09 ± 1.97, P < 0.05). Except skin thickness, all the remaining scores of the signs of benign and malignant breast tumors showed a significant difference between the two groups (P < 0.05). By receiver operating curve (ROC) analysis, the best critical value of the total score of direct signs was ≥ 4, with a sensitivity and specificity of 0.84 and 0.93, respectively, in distinguishing breast carcinoma from benign lesions. The best critical value of the total score of indirect signs was ≥ 1, with a sensitivity and specificity of 0.82 and 0.74, respectively. The critical value of the combination of the direct and indirect signs was ≥ 5 in differential diagnosis of malignant and benign lesions, with a sensitivity and specificity value of 0.88 and 0.90, respectively.</p><p><b>CONCLUSION</b>The assignment score to the ultrasound characteristics of the direct and indirect signs of solid breast lesions can make a more objective diagnosis, yet it is a simple, effective, comprehensive and semi-quantitative analysis method.</p>

Influence of intranasal instilled titanium dioxide nanoparticles on monoaminergic neurotransmitters of female mice at different exposure time / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the influence of intranasal instilling titanium dioxide (TiO2) nanoparticles on monoaminergic neurotransmitters at different-time exposure.</p><p><b>METHODS</b>CD female mice were intranasally instilled three different-sized (25 nm, 80 nm and 155 nm) TiO, suspension every other day in a dose of 50 mg/kg body weight. The control group was instilled the same volume of Milli-Q water. Inductively coupled plasma-mass spectrometry (ICP-MS) was used to analyze the titanium contents in murine brain after exposure to TiO2 particles 2 days, 10 days, 20 days and 30 days. The monoaminergic neurotransmitters such as norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT), 5-hydroxyindole acetic acid (5-HIAA), 3, 4-dihydroxyphenylacetic acid (DOPAC), and homovanillic (HVA), were determined by reversed-phase high performance liquid chromatography (RP-HPLC) with electrochemical detector.</p><p><b>RESULTS</b>After exposure to TiO, nanoparticles 10 days, the titanium contents in murine brain were increased, the titanium content in the 25 nm group was up to (1059.3 +/- 293.5) ng/g. In 20 days, the titanium content decreased slowly with the metabolism of titanium in vivo, but it kept at a high level, the content decreased to (654.7 +/- 269.2) ng/g in the 25 nm group. After exposure to TiO2 nanoparticles 30 days, the titanium contents had no obviously change. Because of the accumulation of TiO, in the brain, the contents of NE and 5-HT increased significantly after exposure to 80 nm and 155 nm TiO, nanoparticles 20 days, while the decreased contents of DA, DOPAC, HVA and 5-HIAA were observed.</p><p><b>CONCLUSION</b>The inhaled TiO2 nanoparticles could be translocated to and deposited in murine brain after absorbing by nasal mucosa, and further influence the releases and metabolisms of monoaminergic neurotransmitters in brain.</p>