Objective To investigate the relationship between pharmacokinetics(PK) and pharmacodynamics PD of epigoitrin,a main component in total alkaloids of Radix Isatidis,in yeast-induced febrile rats with the combined PK-PD model.Methods The plasma concentration of epigoitrin after ig administration with total alkaloids of Radix Isatidis was determined by HPLC method and the body temperature was recorded by electronic thermometer.The individual PK parameters were fitted using one compartmental model.The PD parameters were fitted by three kinds of PK-PD binding models,such as indirect inhibition-Kin model,indirect stimulation KoutPD model,and Sigmoid-Emax model.Results The main PK parameters t1/2,Cmax,AUC were(4.94?0.84) h,(4.01?0.21) ?g/mL,(28.37?2.42) ?g?h/mL and(5.71?0.91) h,(4.15?0.25) ?g/mL,(30.35?2.58) ?g?h/mL in both normal and febrile rats,respectively.The relationship between pharmacological effects and effect compartment concentration was better fitted with the indirect inhibition-Kin PD model.The corresponding PD parameters were Kin=(0.70?0.10) h-1,Kout=(0.54?0.12) h-1,R0=1.33?0.16,IC50=(0.94?0.66) mg/L.ConclusionThe PK parameters of epigoitrin in total alkaloids of Radix Isatidis show that there is no significant difference in PD behavior in vivo in both normal and febrile rats.Relationship between in vivo PK and PD of epigoitrin in febrile rats is established using indirect inhibition Kin model.

Aim: To study the pharmacokinetic effects of salvianolic acid B( Sal B) on danshensu( DSS) in Danshen injection in rats. MGthod: Following the intravenous administration of Danshen injection and Danshen injection added with Sal B to rats, the plasma kinetic study, tissue distribution and urine excretion were studied. The plasma kinetic study was also investigated by giving DSS and DSS in combination with Sal B to rats. Plasma, tissue and urine drug levels of danshensu were analyzed by LC-MS. Results: Compared with danshensu given alone, no significant difference of the pharmacokinetic behavior of danshensu was found when danshensu was given in combination with salvianolic acid B. However, compared with Danshen injection given alone, the pharmacokinetic behavior of danshensu changed remarkably when Danshen injection was given in combination with salvianolic acid B which might be caused by the decrease of DSS in kidney distribution and urine excretion. Conclusion: The pharmacokinetic effects of salvianolic acid B on danshensu depend on the existence of multiple components in Danshen injection. Results suggest that the pharmacokinetic interactions of the multiple components are closely related to the integrity of herbal medicines.

Aim: To determine the uptake characteristics of salvianolic acid B(Sal B) in myocardial cells and blood vessel endothelial cells. Method: The effects of various factors, such as time, temperature, drug concentration, pH of the medium, on the uptake of Sal B in myocardial cells and aorta endothelial cells were investigated. LC/MS was employed to determine the intracellular concentration of Sal B. Results: Uptake kinetics of Sal B in the myocardial cells and aorta endothelial cells fitted well to the logarithmic model at 37 ℃ and 4 ℃. The a-mount of uptake was in direct proportion to the extracellular concentration of Sal B in the experimental concentration range. Uptake of Sal B both in the myocardial cells and blood vessel endothelial cells would significantly increase while the medium pH decreased, and some water-soluble components extracted from danshen would also facilitate the uptake of Sal B both in the myocardial cells and blood vessel endothelial cells obviously. The energy metabolism inhibitors would significantly inhibit the uptake of Sal B in the myocardial cells and blood vessel endothelial cells. When lactic acid and fatty acid were added to the incubation solution, the uptake of Sal B both in the myocardial cells and aorta endothelial cells increased more than 20%. Conclusion: pH is the most important factor influencing the cellular uptake of Sal B, and the amount of uptake tends to increase in acidic medium. Results suggest that the uptake of Sal B would increase in the acidified internal environment induced by myocardial ischemia, thus exerting better cardiovascular activities.

BACKGROUND:There are many methods in the clinic to treat pelvic fractures, mainly conservative treatment, internal fixation and external fixation. Conservative treatment often causes complications due to poor reduction after fractures. Fixation has good effects on repair of unstable fractures, but fixation is seldom used for pelvic fractures.
OBJECTIVE:To observe the effects of internal fixation on unstable pelvic fractures, and compare with conservative treatment and external fixation.
METHODS:126 cases of unstable pelvic fractures from Longhua District People’s Hospital of Shenzhen City from January 2008 to June 2014 were divided into three groups:conservative treatment group, external fixation group and internal fixation group (n=42). After treatment, patients received X-ray examination. Lindahl imaging criteria were used as evidence. The quality of fracture reduction was evaluated. Patients were regularly fol owed up after treatment. The recovery of limb function was evaluated according to Majeed standard. Repair effects, the excel ent and good rates of fracture healing and cal us growth were evaluated in the last fol ow-up.
RESULTS AND CONCLUSION:During the last fol ow-up, the total efficiency was 81%in the internal fixation group, 69%in the conservative treatment group, and 71%in the external fixation group, and results were significantly better in the internal fixation group than in the other two groups (P<0.05). The Lindahl and Majeed scores were significantly higher in the internal fixation group than in the other two groups (P<0.05). These results suggest that internal fixation for unstable pelvic fracture obtained better recovery effects and efficiency than conservative treatment and external fixation. Thus, the internal fixation is more suitable for patients with unstable pelvic fractures.

Objective:To evaluate the anterior expansion of sacral foramen and decompression of sacral plexus via the lateral-rectus approach (LRA) in the surgical treatment of sacral fractures complicated with sacral plexus injury.Methods:From January 2013 to June 2018, 11 patients were treated at Department of Orthopaedics, The Third Hospital Affiliated to Southern Medical University for obsolete sacral fractures complicated with sacral plexus injury. They were 8 males and 3 females, aged from 17 to 54 years (average, 38 years). According to the Denis classification, all the sacral fractures belonged to Denis Zone Ⅱ. According to British Medical Research Council (BMRC) grading system, the nerve injury was complete damage in 2 cases and partial damage in 9. The mean time from injury to surgery was 6 months (range, from 0.7 to 12.0 months). After the sacroiliac joint was exposed via the LRA, the lumbosacral trunk was exposed and released between iliac vessels and the iliopsoas. Next, the S1 foramen was expanded and the S1 nerve root was released after separation of the median sacral artery and the internal iliac artery. Reduction and fixation of the sacroiliac joint was carried out for patients with unstable sacral fracture. X-ray and CT examinations of the pelvis were performed to evaluate fracture healing and neurological function recovery postoperatively.Results:Of this cohort of 11 cases, operation succeeded in 10 but failed in one whose sacral fracture was found to have completely healed with the S1 foramina totally occluded. The surgical time averaged 110 min (range, from 70 to 220 min) and the blood loss 1, 100 mL (range, from 450 to 2, 800 mL). Postoperative X-ray and CT examinations showed that the sacral foramens were expanded significantly without any complications. The follow-up time averaged 18 months (range, from 12 months to 4 years). By the BMRC grading system at the last follow-up, the neural function was completely recovered in 5 cases, partially recovered in 4 cases and not recovered in one.Conclusion:Significant anterior expansion of sacral foramen and decompression of sacral plexus via the LRA is a viable and effective alternative for treatment of sacral fractures complicated with sacral plexus injury.

Objective:To explore the efficacyof direct anterior approach (DAA) combined with direct posterior approach (DPA) for the treatment of Pipkin IV fracture.Methods:Data of 18 patients with Pipkin IV fracture treated through DAA combined with DPA from January 2016 to April 2019 was retrospectively analyzed. There were 13 males and 5 females, with an average age of 43.2 years (range,19-56 years). Fractures were caused by traffic accident in 15 and by falling in 3. The fracture lines of 13 cases were located below the fovea of the femoral head and 5 cases were located above the fovea. According to Letournel-Judet classification for acetabular fractures, there were 14 cases of posterior acetabular wall fractures, 2 cases of posterior wall fractures involving posterior column, and 2 transverse plus posterior wall fractures. The operation was performed through DAA approach to treat the femoral head fractures, and DPA approach was used to treat acetabular fractures. Radiographs and CT scans of the pelvis were reexamined after surgery, and fracture reduction, healing, and complications such as femoral head necrosis, sciatic nerve injury, superior gluteal neurovascular injury and heterotopic ossification were evaluated. Quality of acetabular reduction was evaluated according to the criteria proposed by Matta. Thompson-Epstein scoring system was used to evaluate hip function.Results:The average operation time was 133 min (range, 75-205 min). And the average blood loss was 371 ml (range, 240-600 ml). All 18 patients were followed up for 6 to 36 months, with an average period of 15.7 months. All fractures healed 10 to14 weeks after surgery. Three patients had symptoms of sciatic nerve injury after the injury, who recovered 6 to 12 weeks after the operation. All femoral head fractures were reduced. According to Matta criteria of reduction quality, anatomic reduction was gained in 13 cases, and satisfactory reduction was obtained in 3 cases, while unsatisfactory reduction was found in 2 cases, and the overall satisfactory rate was 88.9%(16/18). Two patients had Brooker I level heterotopic ossification. There was no iatrogenic vascular injury, avascular necrosis of femoral head, infection, internal fixation failure or other complications. According to the Thompson-Epstein scoring system at the latest follow-up, the functional results of the affected hip were excellent in 7 cases, good in 8, fair in 2 and poor in 1.Conclusion:Treatment of Pipkin IV fractures through DAA combined with DPA approach reduces surgical invasion. And it can directly reduce and fix the femoral head and posterior acetabular fracture, and protect the important structures such as the arteriae circumflexa femoris medialis, sciatic nerve and lateral femoral cutaneous nerve, and reduce the occurrence of complications such as femoral head necrosis and heterotopic ossification. Therefore, DAA combined with DPA is aneffective method for the treatment of Pipkin IV fractures.

ObjectiveTo investigate the clinical pharmacokinetics (PK) and pharmacodynamics (PD) of gemifloxacin tablet in healthy Chinese volunteers and to provide evidences for optimal clinical dosing.MethodsTwenty volunteers were enrolled in the randomized (1∶1) double-blind study,and divided into administration group and control group.Each group received multiple oral doses of 320 mg of gemifloxacin tablet or placebo.The plasma and urine samples for gemifloxacin were analyzed by igh-performance liquid chromatogram(HPLC)-fluorometricmethod. Theminimuminhibition concentrations (MIC)of gemifloxacin against190clinical isolateswere determinedby broth microdilution method.The fAUC0～24 h/MIC and fCmax/MIC,with target value of 25 and 5,were used as the indices to evaluate PK and PD characteristics of gemifloxacin. The cumulative fraction of response (CFR) of gemifloxacin against each bacterium and the probability of target attainment (PTA) under various MIC level were evaluated using Monte Carlo simulation following multiple administration at steady state.ResultsThe Cmax of gemifloxacin after once-daily oral doses for 7 days were (1.55 ±0.32) μg/mL and (1.57±0.31) μg/mL for the first and last dose,while the AUC0～24 h were (7.91±1.52) and (8.91±1.15) h · μg · mL-1,respectively.The accumulation factor was 1.13±0.05.The time-profile of gemifloxacin could be described using two-compartment model and the half-life of distribution and elimination phase were (0.64 ± 0.17) and (7.10 ± 2.10) h,respectively. The cumulative urinary excretion rates within 24 h of gemifloxacin were 34.83 ％ and 38.95 ％ for the first and the last dose,respectively.PD study showed that the MIC90 of gemifloxacin were 0.25 mg/L and 0.125 mg/L against Streptococcus pneumoniae and Moraxelle catarrhalis,respectively,while the MIC90 was 2 mg/L against Hemophilus influenza. However,most of Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA) were resistant to gemifloxacin ( MIC90 ＞ 32mg/L).The PTA values of fAUC0～24 h/MIC and fCmax/MIC of gemifloxacin 320 mg daily for 7 days were close to 100％ when MIC was ≤0.06 mg/L.ConclusionsGemifloxacin is rapidly absorbed after oral administration of single doses in healthy Chinese volunteers,and the plasma concentration could reach steady state at the third day,while a minimal accumulation is shown after consecutive 7 days dosing.The PK/PD analysis suggests that the favorable clinical and bacteriological efficacy could be obtained when using thisregimen in treatment of sensitive patients with community-acquired pneumonia and acute exacerbation of chronic obstructive pulmonary disease.

Objective To investigate the feasibility of T2 mapping in evaluating the composition of shoulder cartilage,and to quantitatively analyze T2 values of articular cartilage in healthy young volunteers.Methods Oblique coronal T2 mapping imaging with 8 echo was performed in bilateral shoulder of 16 young healthy volunteers.The pseudo-color map was obtained with post-processing.The shoulder joint cartilage was equally divided into the external,central and internal zones,and T2 values were measured quantitatively.T2 values in the external,central and internal zones were analyzed and compared.T2 values of cartilage between male and female volunteers as well as between left and right sides were analyzed.Resuits T2 values in the external,central and internal zones of cartilage were (38.67 ± 2.82)ms,(38.41 ± 2.52)ms and (36.49± 1.80)ms,respectively.The overall difference was statistically significant (F=7.789,P=0.001).T2 values in the external and central zones of cartilage were larger than those in the internal zone (both P＜0.05).T2 values of cartilagehad no significant differences between the left and right sides in the external,central and internal zones (all P＞0.05).There was significant difference of T2 value in the central zone (P＜0.05),while no significant difference of T2 value in the external and internal zones between different genders was found (both P＞0.05).Conclusion T2 mapping imaging can be used to evaluate the composition of shoulder cartilage changes.

Objective: The proposal of this study is to determine the feasibility of using online social software to guide popular opinion leaders(POLs) among young students MSM (men who have sex with men, MSM) carrying out comprehensive AIDS prevention in young students MSM. Methods: From November to December 2019 in Tianjin, 22 POLs who had previously experienced AIDS prevention education and training foucus on life skills were recruited. Though snowball sampling method, 100 POLs partners (friends, sexual partners, classmates, etc) were invited into the study. From January to March 2020, regular posters will be sent through the WeChat platform to guide POL to intervene their partners/sexual partners. The questionnaire surveys were conducted before and after the intervention. Results: After the intervention, both the proportion of young students MSM had sex and with multiple sex partners decreased(χ2=12.12, 5.94, P<0.05). The comprehensive ability of AIDS prevention has improved significantly, the "National Eight Items" correct rate has risen from 90.0% to 99.0%(χ2=5.82, 7.56, P<0.05), and the "Youth Eight Items" correct rate has increased from 86.0% to 98.0%(P<0.01). Knowledge score increased from(11.08±1.89) to (11.84±1.27); Attitude score increased from (54.29±4.01) to (56.06±3.75), the behavior score increased from (52.12±4.78) to (55.08±4.25), skill score increased from (51.96±4.75) to (54.67±5.04), The comprehensive prevention ability score (percent) increased from (87.30±6.95) to (91.86±5.42)(t=-4.21, -3.51, -5.32, -5.16, -6.45, P<0.01). Conclusion Using Wechat platform to guide POL carrying out comprehensive AIDS prevention is effective for improving the comprehensive AIDS prevention ability of young students MSM.

Objective: To understand the characteristics of sexual partners and the influence of having multiple sexual partners on substance use among young male students man who have sex with men (MSM) in China, and to provide scientific basis for the prevention and control of HIV/AIDS among young MSM students. Methods: A mixed recruitment method of snowball sampling and respondent driven sampling was used to recruit young MSM students in Beijing and Tianjin, and a questionnaire survey was conducted among 220 participants from November to December 2019. Chi-square test and generalized linear model multi-factor Logistic regression were used to analyze the influencing factors of substance use before sexual behavior. Results: The average age of them was (22.39±2.57) years old, 84.5% of them were students, the average age of first sexual behavior was (18.83±2.45) years old, 44.1% of them had two or more sexual partners (including fixed sexual partners, temporary sexual partners and commercial sexual partners), 22.7% had more than one male fixed partner. After adjusting for age and education, having multiple sexual partners was risk factor for drinking alcohol before sex (aOR=2.97) or substance abuse (aOR=2.39). Having male temporary sexual partner was an risk factor in substance use before sexual behavior(OR=4.10). Conclusion The characteristics of sexual partners among young MSM students are complex, and the proportion of multiple sexual partners is high. Having fixed single sexual partner can reduce the risk of substance use before sexual behavior. AIDS prevention education for young MSM students should be further strengthened.