1.Bacterial-killing effect of atmospheric pressure non-equilibrium plasma jet and oral mucosa response.
Dexi, LIU ; Zilan, XIONG ; Tianfeng DU ; Xincai ZHOU ; Yingguang CAO ; Xinpei LU
Journal of Huazhong University of Science and Technology (Medical Sciences) 2011;31(6):852-6
Recently, plasma sterilization has attracted increasing attention in dental community for the atmospheric pressure non-equilibrium plasma jet (APNPs), which is driven by a kilohertz pulsed DC power, may be applied to the dental and oral diseases. However, it is still in doubt whether APNPs can effectively kill pathogenic bacteria in the oral cavity and produce no harmful effects on normal oral tissues, especially on normal mucosa. The aim of this study was to evaluate the bacterial-killing effect of APNPs in the biofilms containing a single breed of bacteria (Porphyromonas gingivalis, P.g.), and the pathological changes of the oral mucosa after treatment by APNPs. P.g. was incubated to form the biofilms in vitro, and the samples were divided into three groups randomly: group A (blank control); group B in which the biofilms were treated by APNPs (the setting of the equipment: 10 kHz, 1600 ns and 8 kV); group C in which the biofilms were exposed only to a gas jet without ignition of the plasma. Each group had three samples and each sample was processed for up to 5 min. The biofilms were then fluorescently stained, observed and photographed under a laser scanning confocal microscope. In the animal experiment, six male Japanese white rabbits were divided into two groups randomly (n=3 in each group) in terms of the different post-treatment time (1-day group and 5-day group). The buccal mucosa of the left side and the mucosa of the ventral surface of the tongue were treated by APNPs for 10 min in the same way as the bacterial biofilm experiment in each rabbit, and the corresponding mucosa of the other sides served as normal control. The clinical manifestations of the oral mucosa were observed and recorded every day. The rabbits were sacrificed one or five day(s) after APNPs treatment. The oral mucosa were harvested and prepared to haematoxylin and eosin-stained sections. Clinical observation and histopathological scores were used to assess mucosal changes. The results showed the obvious P.g. biofilms were formed at 10 days, and most of the bacteria in groups A and C were alive under a laser scanning confocal microscope, but the bacteria in the group B were almost all dead. In animal experiment, no ulcers, anabrosis and oral mucositis were found in both the 1-day and 5-day groups. The average mucous membrane irritation index was -0.83 and -0.67 in the 1-day and 5-day groups, respectively, suggesting that no intense mucosal membrane irritation responses occurred. It was concluded that APNPs could effectively kill P.g. in the biofilms and did not cause any pathological changes in the normal mucosa, suggesting that the plasma jet (APNPs) may be applied to oral diseases as a novel sterilization device in the future.
2.Bacterial-killing Effect of Atmospheric Pressure Non-equilibrium Plasma Jet and Oral Mucosa Response
LIU DEXI ; XIONG ZILAN ; DU TIANFENG ; ZHOU XINCAI ; CAO YINGGUANG ; LU XINPEI
Journal of Huazhong University of Science and Technology (Medical Sciences) 2011;31(6):852-856
Recently,plasma sterilization has attracted increasing attention in dental community for the atmospheric pressure non-equilibrium plasma jet (APNPs),which is driven by a kilohertz pulsed DC power,may be applied to the dental and oral diseases.However,it is still in doubt whether APNPs can effectively kill pathogenic bacteria in the oral cavity and produce no harmful effects on normal oral tissues,especially on normal mucosa.The aim of this study was to evaluate the bacterial-killing effect of APNPs in the biofilms containing a single breed of bacteria (Porphyromonas gingivalis,Pg.),and the pathological changes of the oral mucosa after treatment by APNPs.Pg.was incubated to form the biofilms in vitro,and the samples were divided into three groups randomly:group A (blank control);group B in which the biofilms were treated by APNPs (the setting of the equipment:10 kHz,1600 ns and 8 kV); group C in which the biofilms were exposed only to a gas jet without ignition of the plasma.Each group had three samples and each sample was processed for up to 5 min.The biofilms were then fluorescently stained,observed and photographed under a laser scanning confocal microscope.In the animal experiment,six male Japanese white rabbits were divided into two groups randomly (n=3 in each group) in terms of the different post-treatment time (1-day group and 5-day group).The buccal mucosa of the left side and the mucosa of the ventral surface of the tongue were treated by APNPs for 10 min in the same way as the bacterial biofilm experiment in each rabbit,and the corresponding mucosa of the other sides served as normal control.The clinical manifestations of the oral mucosa were observed and recorded every day.The rabbits were sacrificed one or five day(s) after APNPs treatment.The oral mucosa were harvested and prepared to haematoxylin and eosin-stained sections.Clinical observation and histopathological scores were used to assess mucosal changes.The results showed the obvious P.g.biofilms were formed at 10 days,and most of the bacteria in groups A and C were alive under a laser scanning confocal microscope,but the bacteria in the group B were almost all dead.In animal experiment,no ulcers,anabrosis and oral mucositis were found in both the 1-day and 5-day groups.The average mucous membrane irritation index was -0.83 and -0.67 in the 1-day and 5-day groups,respectively,suggesting that no intense mucosal membrane irritation responses occurred.It was concluded that APNPs could effectively kill P.g.in the biofilms and did not cause any pathological changes in the normal mucosa,suggesting that the plasma jet (APNPs) may be applied to oral diseases as a novel sterilization device in the future.
3.Establishment of a method for detecting peripheral blood circulating brain microvascular endothelial cells, a novel biomarker for blood-brain barrier injury.
Yan LI ; Lei DU ; Lin YUAN ; Dexi CHEN ; Jiawen QIU ; Xiaolong HE ; Hong CAO ; Shenghe HUANG
Journal of Southern Medical University 2014;34(12):1733-1737
OBJECTIVETo establish a method for detecting circulating brain microvascular endothelial cells (cBMECs), a novel biomarker of blood-brain barrier (BBB) injury.
METHODSBlood samples were collected from 33 patients with AIDS encephalitis and 13 healthy subjects for detection of cBMECs, cECs and EPCs using magnetic affinity isolation and immune identification technology.
RESULTSThe numbers of cBMECs, cECs and EPCs were significantly higher in the AIDS patients than in the control subjects (t=4.298, P<0.01; t=4.886, P<0.01; t=4.889, P<0.01). An significant association was also noted between HIV load and cBMEC number (r=0.928, P<0.01).
CONCLUSIONWe have successfully established a method for detecting peripheral blood cBMECs, which can be of important value in non-invasive assessment of BBB injury.
Acquired Immunodeficiency Syndrome ; physiopathology ; Biomarkers ; Blood-Brain Barrier ; pathology ; Cell Separation ; methods ; Cells, Cultured ; Endothelial Progenitor Cells ; cytology ; Humans
4.Effect of simultaneous integrated boost intensity-modulated radiation therapy on lateral lymph node metastasis in rectal cancer
Jinxia SHEN ; Dexi DU ; Huijuan HE ; Ming LI ; Zhenzhen ZHOU ; Shubo DING
Chinese Journal of Radiological Medicine and Protection 2023;43(11):866-872
Objective:To evaluate the efficacy and safety of simultaneous integrated boost intensity-modulated radiation therapy (SIB-IMRT) for rectal cancer with lateral lymph node metastasis (LLNM).Methods:From January 2016 to December 2022, 103 rectal cancer patients with LLNM were enrolled. The patients were divided into SIB-IMRT group (52 cases) and conventional chemoradiotherapy (CRT) group (51 cases) using the random number table method. The dose was 50 Gy for the pelvis with 60 Gy of SIB-IMRT for the LLNM in the SIB-IMRT group. The dose was 50 Gy for the pelvis in the CRT group. The primary endpoint was the lateral recurrence rate. The efficacy and adverse reactions of the two groups were compared.Results:The adverse reactions and surgical complications after neoadjuvant radiotherapy were comparable between the two groups. The response rates of LLNM treatment were 76.9% and 56.9%, respectively, in the two groups ( χ2=4.69, P=0.03). The SIB-IMRT group and CRT group had a local recurrence rate of 7.7% and 25.5% ( χ2=5.92, P=0.015), respectively, and a lateral recurrence rate of 3.8% and 23.5% ( χ2=8.49, P=0.004), respectively. Univariate analysis showed that the SIB-IMRT, short axis of lateral lymph nodes <5 mm after radiotherapy, and negative result in the postoperative lymph node pathological examination were factors associated with lateral recurrence. Multivariable regression analysis demonstrated that the SIB-IMRT ( HR=6.42, 95% CI: 1.40-29.49) and short axis of lateral lymph nodes <5 mm after radiotherapy ( HR=0.17, 95% CI: 0.04-0.66) were independent factors associated with lateral recurrence. The two groups had a 3-year disease-free survival of 73.25% and 62.6% ( P>0.05), respectively, and a 3-year overall survival of 87% and 82.5% ( P>0.05), respectively. Conclusions:The SIB-IMRT is safe and effective for rectal cancer with LLNM. The short axis of lateral lymph nodes <5 mm after neoadjuvant radiotherapy and SIB-IMRT is an independent risk factor for lateral recurrence.