1.Optical Properties and Biomedical Application of Gold Nanorods
Mei LIU ; Peihui YANG ; Jiye CAI
Progress in Biochemistry and Biophysics 2009;36(11):1402-1407
Gold nanorods is a capsule-shaped gold nanoparticles. Gold nanorods give rise to two absorption peaks corresponding to their plasmonic modes, transverse mode and longitudinal mode, corresponding to light absorption and scattering along the short and long axis, respectively. The longitudinal surface plasmon resonance can be tuned by adjusting their aspect ratio from the visible to the NIR region and extremely sensitive to changes in the dielectric properties of the surroundings including solvents, adsorbates, and the interparticle distance of the gold nanorods. This unique optical property of gold nanorods opens up fascinating applications in biological and chemical sensors. Optical properties and biomedical application of gold nanorods are introduced, and its future research prospects are discussed.
2.A retrospective analysis on the incidence and treatment outcomes of retinopathy of prematurity among extremely preterm infants
Chaohui LIAN ; Guoming ZHANG ; Bingchun LIN ; Song TANG ; Peihui LIU ; Chuanzhong YANG
Chinese Pediatric Emergency Medicine 2015;22(7):491-493
Objective To analyze the incidence of retinopathy of prematurity(ROP)among extreme-ly preterm infants,and to evaluate the treatment methods and effects among those with severe ROP.Methods A retrospective analysis was performed to analyze incidence of ROP in 96 cases of extremely preterm infants who were born at a gestational age of 〈28 weeks and survived beyond a postmenstrual age of at least 1 year from Apr 2006 to Oct 2013,and to analyze the treatment outcomes of photocoagulation and ranibizum-ab intravitreal injection among the infants with severe ROP.Results Fifty-six of 96 cases(58.33%)grew into ROP finally and 21 cases(21.88%)grew into severe ROP,2 cases(2.08%)grew into aggressive poste-rior ROP.Fifteen cases with severe ROP were treated with laser photocoagulation.Four cases with severe ROP were received ranibizumab intravitreal injection prior to photocoagulation.Two cases with severe ROP were only treated with ranibizumab intravitreal injection.The eyesight of 96 patients (100%)in this study were all preserved.Conclusion ROP screening should focus on extremely preterm infants because of higher incidence of ROP and severe ROP among them.The infants with severe ROP should be treated with laser photocoagulation in time.The infants in critical condition or with aggressive posterior ROP can be treated with ranibizumab injection.
3.Pre-clinical application of self-developed computer assisted design/rapid prototyping and guidance system to assist precise acetabular component placement: A pilot study
Peihui WU ; Zhitao LIU ; Yingqi ZHANG ; Zibo YANG ; Puyi SHENG ; Guanghua ZHAO ; Yan KANG ; Zhiqi ZHANG ; Ming FU ; Weiming LIAO
Chinese Journal of Orthopaedic Trauma 2017;19(4):323-328
Objective To introduce a self-developed computer-assisted design/rapid prototyping and guidance system used for precise placement of the acetabular component in total hip arthroplasty.Methods We collected the preoperative pelvic CT scanning data of 10 hips with aeetabular dysplasia that had undergone primary total hip arthroplasty from January 2016 to January 2017.The total time for import of radiographic images,model reconstruction,model segmentation,acetabular component position design and STL model export was calculated and compared between our self-designed software and Mimics vl 7.0.Three kinds of STL model from each case were imported into our self-developed 3D printing device,Stratasys Objet30 and Stratasys Demension SST1200es respectively for rapid prototyping.The printing efficiency and accuracy were compared among the 3 printers.The accuracy of placing acetabular component with guidance system was evaluated.Results The average time forpreoperative planningwas7.7±1.3 minbyourself-designedsoftware and 52.5 ± 15.9 min by Mimics v17.0,showing a significant difference (P < 0.001).In morphological point-based comparison for each case,the 3D models exported by the 2 different kinds of software showed an average difference of 0.072 1 ± 0.069 1 mm.The average durations for rapid prototyping by the 3 different printers were 5.3 ± 0.6 h,10.8 ± 0.5 h,and 9.3 ± 0.6 h,respectively,showing significant differences (P < 0.001).The guidance system resulted in precise placement.The locations of the acetabular component achieved by guide-assisted placement were not significantly different from the target ones (P > 0.05).Conelusion Our self-developed preoperative planning software,rapid prototyping device and guidance apparatus for acetabular component placement may lead to good accuracy and high efficiency.
4.Effect of lipopolysaccharide exposure on neuro-immune system of rat offspring with autism spectrum disorder at second trimester
Jindou HAO ; Jun DUAN ; Peihui LIU ; De WU
Chinese Journal of Applied Clinical Pediatrics 2018;33(7):534-537
Objective To establish the lipopolysaccharide(LPS)-induced autism spectrum disorder(ASD) models at second trimester in rat offspring,and to investigate the effect of LPS exposure on social interaction behavior and neuro-immune system in rat offspring.Methods Twelve-week-old pregnant specific pathogen free rats were randomly divided into non-exposed group(10 cases) and LPS-exposed group(10 cases).Rats in the exposure group were intraperitoneally injected with LPS 25 mg/kg at 12.5 d,while rats in the non-exposed group were intraperitoneally injected with 9 g/L saline.At the age of 28 days,10 rats were randomly selected from each group as the experimental group and the control group.The following tests were carried out in two groups of rats.Their offspring were randomly allocated to the control group (10 cases) and the experimental group (10 cases).The autism-like social behaviors were evaluated by the social interaction test.Density of dendritic spine was analyzed by Golgi staining.The expression of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (IBA1) were analyzed by immunohistochemisty.The levels of i nterleukin (IL)-1 β,IL-4,IL-6,IL-10,interferon-gamma (IFN-γ'),and transforming growth factor-beta(TGF-β) in rat offspring were detected by enzyme-linked immunosorbent assay.Results The score of social interaction test in the experimental group [(-197.81 ± 101.83) scores] was lower than that in the control group [(132.73 ± 114.63) scores],and the difference was statistically significant (t =5.453,P < 0.05).Density of dendritic spine in CA1 region of hippocampus was lower in the experimental group[(7.71 ± 1.33) numbers/10 μm] than that in the control group[(9.66 ± 1.76) numbers/10 μm] by Golgi staining,and the difference was statistically significant(t =2.775,P < 0.05).Expressions of GFAP and IBA1 in experimental group were higher than those in the control group by immunohistochemisty.Levels of IL-1 β,IL-6,IL-10 and IFN-γ in the experimental group were higher than those in the control group,while level of TGF-β was lower than that in the control group,and the differences were statistically significant(all P <0.05).The scores of social interaction test were correlated with the levels of IFN-γ(r =0.756,P < 0.05).Conclusion LPS exposure at early pregnancy may affect the neuro-immune system of rat offspring and result in autism-like behavior.
5. Keratinized tissue augmentation techniques around dental implants
Jiaping HUANG ; Peihui DING ; Jiamei LIU ; Yanmin WU
Chinese Journal of Stomatology 2020;55(2):129-134
Research have indicated that inadequate keratinized tissue has a negative effect on patient oral hygiene, resulting in peri-implant inflammation. It has been recommended that an apically repositioned flap alone or in combination with autogenous soft tissue grafts can increase the width of keratinized mucosa around dental implants, which promotes long term peri-implant health. This review summarized research progress on augmentation techniques of keratinized tissue arround implants in recent years, so as to provide reference for clinical practice and research design in the future.
6.Metabolic labeling of Porphyromonas gingivalis and comparison of two fluorescent probes for in vivo imaging
CHENG Xinyi ; ZOU Peihui ; LIU Jia ; LUAN Qingxian
Journal of Prevention and Treatment for Stomatological Diseases 2024;32(9):664-673
Objective:
To investigate the impact of metabolic labeling on Porphyromonas gingivalis (Pg) and compare the imaging effects of two fluorescent probes.
Methods:
This study was reviewed by the unit Ethics Committee and was approved by the Experimental Animal Welfare Ethics Branch of the Unit Experimental Biomedical Ethics Committee. Pg integrated N-azidoacetylgalactosamine (Ac4GalNAz) via a bioorthogonal reaction and was labeled with Cy5-DBCO or Cy7-DBCO via a click chemistry reaction. The bacteria were divided into Pg group (control, not fluorescently labeled), Cy5-Pg group (tagged by Cy5-DBCO), and Cy7-Pg group (tagged by Cy7-DBCO). A live/dead staining kit was applied to test the viability of Pg, Cy5-Pg, and Cy7-Pg. The mRNA levels of interleukin-6 (IL-6) and IL-8 and cell proliferation were examined in human gingival fibroblasts (HGFs) after the challenge of Cy5-Pg, Cy7-Pg, or Pg. To investigate the stability of metabolic labeling, Cy5-Pg or Cy7-Pg was cocultured with Escherichia coli (E. coli). Cy5-Pg and Cy7-Pg signal intensity with serial dilutions were examined using an in vivo imaging system (IVIS). Finally, C57BL/6J mice were orally administered Cy5-Pg or Cy7-Pg for IVIS detection, and the signal-to-background ratios were calculated.
Results :
Metabolic labeling could be applied to label live Pg in vitro. The optimal labeling concentrations for Cy5 and Cy7 were 20 μmol/L and 30 μmol/L, respectively. The area ratios of live to dead bacteria were approximately 2.0 in the three groups (F = 0.318, P>0.05). After a 6-h challenge with Cy5-Pg, Cy7-Pg, or Pg, the mRNA levels of HGFs increased by 7.86-, 7.46-, and 6.56-fold for IL-6, respectively (F = 40.886, P<0.001) and 12.43-, 13.03-, and 13.71-fold for IL-8 (F = 18.781, P<0.01), were spectively, compared to that of the Ctrl group, which was not challenged by bacteria, where no significant differences were observed among the three groups (P>0.05). HGFs were further challenged by Cy5-Pg, Cy7-Pg, or Pg at different MOIs, and cell proliferation was significantly inhibited (MOI = 104∶1, F = 153.52, P<0.001; MOI = 105∶1, F = 331.21, P<0.001; MOI = 106∶1, F = 533.65, P<0.001), with no significant differences among the three groups (P>0.05). Within 24 h of co-culturing Cy5-Pg or Cy7-Pg with E. coli, minimal E. coli was detected. The intensities of Cy5 and Cy7 remained stable for 3 h. Additionally, the fluorescence signal intensities of Cy5 and Cy7 were linearly correlated with the concentration (R2 = 0.97). After oral gavage of Cy5-Pg or Cy7-Pg in mice for the abdominal region at 1 h and 3 h, the signal-to-background ratios of Cy7-Pg were approximately 4.24-fold (t = 6.893, P<0.01) and 3.77-fold (t = 4.407, P<0.05) higher, respectively, than those of Cy5-Pg. For the isolated gastrointestinal tracts at 3 h, the signal-to-background ratio of Cy7-Pg was 5.19-fold higher than that of Cy5-Pg (t = 4.418, P<0.05).
Conclusions
Metabolic labeling did not significantly affect viability, immunomodulatory ability, and toxicity. The imaging effect of Cy7 on IVIS was better than that of Cy5. Our study provided experimental evidence for the correlation between periodontitis and overall health.