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1.
J Pathol ; 263(2): 203-216, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38551071

ABSTRACT

Urothelial damage and barrier dysfunction emerge as the foremost mechanisms in Hunner-type interstitial cystitis/bladder pain syndrome (HIC). Although treatments aimed at urothelial regeneration and repair have been employed, their therapeutic effectiveness remains limited due to the inadequate understanding of specific cell types involved in damage and the lack of specific molecular targets within these mechanisms. Therefore, we harnessed single-cell RNA sequencing to elucidate the heterogeneity and developmental trajectory of urothelial cells within HIC bladders. Through reclustering, we identified eight distinct clusters of urothelial cells. There was a significant reduction in UPK3A+ umbrella cells and a simultaneous increase in progenitor-like pluripotent cells (PPCs) within the HIC bladder. Pseudotime analysis of the urothelial cells in the HIC bladder revealed that cells faced challenges in differentiating into UPK3A+ umbrella cells, while PPCs exhibited substantial proliferation to compensate for the loss of UPK3A+ umbrella cells. The urothelium in HIC remains unrepaired, despite the substantial proliferation of PPCs. Thus, we propose that inhibiting the pivotal signaling pathways responsible for the injury to UPK3A+ umbrella cells is paramount for restoring the urothelial barrier and alleviating lower urinary tract symptoms in HIC patients. Subsequently, we identified key molecular pathways (TLR3 and NR2F6) associated with the injury of UPK3A+ umbrella cells in HIC urothelium. Finally, we conducted in vitro and in vivo experiments to confirm the potential of the TLR3-NR2F6 axis as a promising therapeutic target for HIC. These findings hold the potential to inhibit urothelial injury, providing promising clues for early diagnosis and functional bladder self-repair strategies for HIC patients. © 2024 The Pathological Society of Great Britain and Ireland.


Subject(s)
Cystitis, Interstitial , Toll-Like Receptor 3 , Urothelium , Urothelium/pathology , Urothelium/metabolism , Cystitis, Interstitial/pathology , Cystitis, Interstitial/metabolism , Cystitis, Interstitial/genetics , Toll-Like Receptor 3/metabolism , Toll-Like Receptor 3/genetics , Humans , Urinary Bladder/pathology , Urinary Bladder/metabolism , Signal Transduction , Female , Animals , Cell Proliferation , Male , Single-Cell Analysis , Cell Differentiation
2.
Neurourol Urodyn ; 43(2): 382-389, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38078752

ABSTRACT

PURPOSE: To design a quick checklist for urodynamic study (UDS), aiming to reduce the occurrence of errors in the process, which may help to increase the quality of UDS. And further to analyze the effectiveness of this quick checklist for UDS quality control. METHODS: First, a quick checklist for uroflow study and pressure-flow study was developed, based on the International Continence Society-Good Urodynamic Practice standards, our previous studies, and recent literature, as well as expert suggestions. Then, patients who underwent UDS between January 2023 to February 2023 were randomly assigned to a study group or a control group. For the study group, the quick checklist was used throughout the UDS process, while the control group did not. The main artefacts were chosen to verify the effectiveness of the quick checklist for improving the UDS quality. RESULTS: The quick checklist comprised three subtypes: checklist for patients, checklist for environment and device, and checklist for UDS test process. 38 UDS traces per group were included. The incidence of missing the standard cough test decreased significantly from 18.4% to 0 (p = 0.012), with the checklist implementation. The baseline drift frequency rate also declined significantly from 39.5% to 5.3% (p < 0.05). Volume < 150 mL on uroflow study occurred in 68.4% of cases and its frequency rate decreased significantly with checklist implementation (p < 0.05). CONCLUSION: A quick checklist for quality control of UDS was developed. The quick checklist as a convenient, quick, and easy used urodynamic quality control method, may help to reduce the technical artefacts and improve fundamental urodynamic quality control. Future research with a larger sample size is needed to confirm the effectiveness of the checklist.


Subject(s)
Checklist , Urodynamics , Humans , Prospective Studies , Quality Control , Reference Standards
3.
Int J Surg ; 110(1): 520-528, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37916939

ABSTRACT

BACKGROUND: Stress urinary incontinence is common among women, and surgical interventions have significantly improved patients' symptoms. The long-term effectiveness of these surgeries is increasingly drawing attention, yet it remains sparsely documented in the literature. OBJECTIVE: To compare the long-term effectiveness and safety of retropubic tension-free vaginal tape (TVT-RP), tension-free vaginal tape-obturator (TVT-O), transobturator tape (TOT), single-incision sling (SIS), Burch colposuspension, and pubovaginal sling (PVS). METHODS: A comprehensive and systematic literature review was conducted in PubMed, EMBASE, MEDLINE, Cochrane Library, Medicine, and clinicaltrials.gov from inception to May 2023. Selected trials were evaluated for potential bias using the Cochrane tool. Treatment modalities were compared using network meta-analysis to assess objective success rate, subjective success rate, and complications as outcomes. RESULTS: A total of 37 studies involving 5720 patients were included. No significant statistical differences were found among the interventions regarding objective success rate. PVS had the highest surface under the cumulative ranking curve SUCRA value (93.1). For subjective success rate, TVT-RP, TVT-O, and PVS demonstrated superiority over SIS, with PVS having the highest SUCRA value (80.1). SIS had lower overall complication and pain rates compared to other methods, with statistical significance. There were no differences in reoperation rate, exposure rate, and urinary tract infection occurrence among the surgical approaches. CONCLUSIONS: In terms of long-term effectiveness and safety, TVT-RP and TVT-O appear to be the preferred options for patients opting for synthetic slings, while for patients seeking nonsynthetic slings, PVS may represent the optimal choice.


Subject(s)
Suburethral Slings , Urinary Incontinence, Stress , Female , Humans , Urinary Incontinence, Stress/surgery , Urinary Incontinence, Stress/etiology , Network Meta-Analysis , Urologic Surgical Procedures/methods , Reoperation , Treatment Outcome
4.
Aging (Albany NY) ; 15(21): 12155-12170, 2023 11 02.
Article in English | MEDLINE | ID: mdl-37925174

ABSTRACT

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a long-lasting and incapacitating disease, and the exact factors that affect its onset and advancement are still uncertain. Thus, the main aim was to explore new biomarkers and possible therapeutic targets for IC/BPS. Next-generation high-throughput sequencing experiments were performed on bladder tissues. Based on the interactions between circRNA and miRNA, as well as miRNA and mRNA, candidates were selected to build a network of circRNA-miRNA-mRNA. The STRING database and Cytoscape software were utilized to build a protein-protein interaction (PPI) network to pinpoint the hub genes associated with IC/BPS. The expression levels of circRNA and miRNA in the network were confirmed through quantitative polymerase chain reaction. Western blot was applied to confirm the stability of the lipopolysaccharide-induced IC/BPS model, and the effect of overexpression of circ.5863 by lentivirus on inflammation. Ten circRNA-miRNA interactions involving three circRNAs and six miRNAs were identified, and IFIT3 and RSAD2 were identified as hub genes in the resulting PPI network with 19 nodes. Circ.5863 showed a statistically significant decrease in the constructed model, which is consistent with the sequencing results, and overexpression via lentiviral transfection of circ.5863 was found to alleviate inflammation damage. In this study, a circRNA-miRNA-mRNA network was successfully constructed, and IFIT3 and RSAD2 were identified as hub genes. Our findings suggest that circ.5863 can mitigate inflammation damage in IC/BPS. The identified marker genes may serve as valuable targets for future research aimed at developing diagnostic tools and more effective therapies for IC/BPS.


Subject(s)
Cystitis, Interstitial , MicroRNAs , Humans , Cystitis, Interstitial/genetics , RNA, Circular/genetics , Inflammation , Biomarkers , MicroRNAs/genetics , RNA, Messenger/genetics
5.
Front Pediatr ; 11: 1271417, 2023.
Article in English | MEDLINE | ID: mdl-38027283

ABSTRACT

Introduction: This prospective study aimed to assess the effectiveness of a Y-shape connection device in reducing pain and bleeding in pediatric patients with indwelling catheters during urodynamic studies (UDS), while also obtaining effective results in the filling phase. Methods: A total of 45 pediatric patients with a mean age of 13 years were included, all of whom underwent both a UDS with the Y-shape connection device (Method A) and a standard UDS procedure (Method B). Results: The Y-shape connection device demonstrated similar overall urodynamic parameters compared to the standard procedure, while also resulting in significantly less bleeding (P = 0.006) and lower VAS scores during (1.12 ± 0.58 vs. 3.88 ± 1.01, P = 0.001) and after (0.12 ± 0.08 vs 2.91 ± 0.89, P = 0.001) the procedure. No adverse events were reported at the 1-month follow-up. Discussion: These findings suggest that the Y-shape connection device can effectively reduce pain and bleeding during and after UDS in pediatric patients with indwelling catheters (Dia = 8Fr), while also obtaining effective results in the filling phase. Therefore, this Y-shape connection device has a more significant value for children who require urodynamic studies and place more emphasis on filling phase parameters. Clinical trial registration: ChiCTR2300068280.

6.
Transl Androl Urol ; 11(12): 1621-1628, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36632161

ABSTRACT

Background: YouTube is commonly used by doctors to learn surgery. To date, no studies have evaluated the quality of videos on photoselective vaporization of the prostate (PVP) for benign prostatic hyperplasia (BPH) on YouTube. Our aim was to assess the educational value of YouTube videos regarding PVP. Methods: "Green light laser vaporization of the prostate" and "photoselective vaporization of the prostate (PVP)" were searched by 2 authors on YouTube on February 14, 2022. Based on the Laparoscopic Surgery Video Educational Guidelines and previous studies, a checklist that included 4 major and 16 minor items was developed. SPSS version 26 (IBM Corp., Armonk, NY, USA) was used to analyze the data using correlation analysis. Results: A total of 74 surgical videos were assessed. The mean number of days available for educational videos was 2,607 days (range, 156-5,854 days), with the earliest videos dating back to 2006 and the latest to 2021. The average length was 12.69 minutes (range, 0.73-123.7, SD 21.25). The majority of videos originated in the United States, and the video definition was divided into high, moderate, and low, accounting for 21.6%, 66.2%, and 12.2% of the videos, respectively. The average numbers of likes and dislikes for videos were 34.26 (SD 87.96) and 0, respectively. The average score of the videos was 6.65 (range, 2-12, SD 2.79). The correlation analysis indicated that the number of views of these videos was related to the number of online days and likes. The scores of videos were related to the number of likes, and the annual average number of views was related to both the number of views and the number of surgeon likes. Conclusions: There is a lack of high-quality surgical videos of green laser vaporization of the prostate on YouTube. More detailed explanations of the key steps of the operation are needed. We hope that more videos with higher educational value will be published in the future to help surgeons master this technology.

7.
Water Environ Res ; 93(6): 844-853, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33131118

ABSTRACT

An indigenous lead-tolerant fungal strain was isolated from lead-contaminated soil and identified as Aspergillus niger, via 18S rRNA gene sequencing. We determined the adsorption and accumulation of Pb(II) by living A. niger and the adsorption of Pb(II) via modified A. niger. This strain resisted and removed 96.21%-100% Pb(II) ranging from 2 to 8 mmol/L Pb(II). Pb-containing particles were observed outside of the cell, and lead was detected inside the cell under scanning electron microscopy and transmission electron microscopy. The process of measuring the adsorption ability of modified fungal biomass, freeze-dried, high-temperature, and alkali-treated fungal samples was analyzed; they adsorbed 25.02%, 8.76%, and 15.05% Pb(II) under 8 mmol/L Pb(II) in 43, 10, and 10 hr, respectively. These three types of modified A. niger fit the pseudo-second-order model equation well. PRACTITIONER POINTS: Isolation and identification of effective Pb(II) removal strain from the soil around Dexing lead-zinc mine. The ability of living and modified Aspergillus niger to remove Pb(II) in an aqueous environment was evaluated. Lead distributions inside and outside the cell were analyzed by SEM and TEM. Kinetic models for modified biomass adsorbing Pb(II) were made for describing adsorption process.


Subject(s)
Aspergillus niger , Water Pollutants, Chemical , Adsorption , Hydrogen-Ion Concentration , Ions , Kinetics , Lead , Water
8.
BMC Plant Biol ; 19(1): 260, 2019 Jun 17.
Article in English | MEDLINE | ID: mdl-31208338

ABSTRACT

BACKGROUND: Drought is a major abiotic stress factor that influences the yield of crops. Basic leucine zipper motif (bZIP) transcription factors play an important regulatory role in plant drought stress responses. However, the functions of a number of bZIP transcription factors in rice are still unknown. RESULTS: In this study, a novel drought stress-related bZIP transcription factor, OsbZIP62, was identified in rice. This gene was selected from a transcriptome analysis of several typical rice varieties with different drought tolerances. OsbZIP62 expression was induced by drought, hydrogen peroxide, and abscisic acid (ABA) treatment. Overexpression of OsbZIP62-VP64 (OsbZIP62V) enhanced the drought tolerance and oxidative stress tolerance of transgenic rice, while osbzip62 mutants exhibited the opposite phenotype. OsbZIP62-GFP was localized to the nucleus, and the N-terminal sequence (amino acids 1-68) was necessary for the transcriptional activation activity of OsbZIP62. RNA-seq analysis showed that the expression of many stress-related genes (e.g., OsGL1, OsNAC10, and DSM2) was upregulated in OsbZIP62V plants. Moreover, OsbZIP62 could bind to the promoters of several putative target genes and could interact with stress/ABA-activated protein kinases (SAPKs). CONCLUSIONS: OsbZIP62 is involved in ABA signalling pathways and positively regulates rice drought tolerance by regulating the expression of genes associated with stress, and this gene could be used for the genetic modification of crops with improved drought tolerance.


Subject(s)
Basic-Leucine Zipper Transcription Factors/physiology , Oryza/genetics , Plant Proteins/genetics , Basic-Leucine Zipper Transcription Factors/genetics , Dehydration , Gene Expression Regulation, Plant , Gene Knockdown Techniques , Oryza/physiology , Oxidative Stress , Plant Proteins/physiology , Plants, Genetically Modified
9.
Can J Microbiol ; 62(4): 329-37, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26928439

ABSTRACT

In this work, we studied the natural bioaccumulation and biosorption of Pb(II) in several common edible macrofungi. The macrofungi include the following species: Lentinus edodes, Pleurotus eryngii, Flammulina velutipes, Hypsizygus marmoreus, and Agrocybe cylindracea. The present analysis of Pb(II) revealed distinct capabilities of metal accumulation among individual species. Moreover, the natural concentrations of lead did not reach a health risk level when cultivated in uncontaminated soil. In the biosorption experiment by edible macrofungi, we found that the equilibrium data of living sporocarp (P. eryngii and H. marmoreus) and the homogenate of L. edodes and F. velutipes fit the Freundlich model well. Other data samples exhibited a better fit to the Langmuir model. The edible macrofungi showed a higher lead removal capacity than did other biosorbents. Furthermore, the pseudo-second-order kinetics model exhibited the best fit to the biosorption processes. The effectiveness of edible macrofungi as biosorbents for Pb(II) was confirmed.


Subject(s)
Agaricales/metabolism , Environmental Pollutants/metabolism , Lead/metabolism , Adsorption , Environmental Pollutants/analysis , Food Contamination , Kinetics , Lead/analysis
10.
Bing Du Xue Bao ; 30(1): 37-43, 2014 Jan.
Article in Chinese | MEDLINE | ID: mdl-24772896

ABSTRACT

This study aims to investigate the characteristics of genomic variation of pandemic A/H1N1/2009 influenza virus isolated in Fujian Province, China. Complete genome sequence analysis was performed on 14 strains of pandemic A/H1N1/2009 influenza virus isolated from Fujian during 2009-2012. All virus strains were typical low-pathogenic influenza viruses, with resistance to amantadine and sensitivity to neuraminidase inhibitors. Eight genome fragments of all strains were closely related to those of A/California/07/2009 (H1N1) vaccine strain, with > or = 98.2% homology. Compared with the vaccine strain, the influenza strains from Fujian had relatively large variation, and variation was identified at 11 amino acid sites of the HA gene of A/Fujiangulou/SWL1155/2012 strain, including 4 sites (H138R, L161I, S185T, and S203T) involved inthree antigen determinants (Ca, Sa, and Sb). In conclusion, the influenza vaccine has a satisfactory protective effect on Fujian population, but the influenza strains from Fujian in 2012 has antigenic drift compared with the vaccine strain, more attention should therefore be paid to the surveillance of mutations of pandemic A/H1N1/2009 influenza virus.


Subject(s)
Genomics , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/physiology , Influenza, Human/epidemiology , Pandemics , Antiviral Agents/pharmacology , China/epidemiology , Drug Resistance, Viral/genetics , Genome, Viral/genetics , Humans , Influenza A Virus, H1N1 Subtype/drug effects , Influenza A Virus, H1N1 Subtype/immunology , Influenza, Human/prevention & control , Pandemics/prevention & control , Viral Vaccines/immunology
11.
Ultrasonics ; 54(3): 929-37, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24295911

ABSTRACT

The vibration characteristics of an aluminum surface subjected to ultrasonic waves were investigated with a combination of numerical simulation and experimental testing. The wetting behavior of solder droplets on the vibrating aluminum surface was also examined. The results show that the vibration pattern of the aluminum surface is inhomogeneous. The amplitude of the aluminum surface exceeds the excitation amplitude in some zones, while the amplitude decreases nearly to zero in other zones. The distribution of the zero-amplitude zones is much less dependent on the strength of the vibration than on the location of the vibration source. The surface of the liquid solder vibrates at an ultrasonic frequency that is higher than the vibration source, and the amplitude of the liquid solder is almost twice that of the aluminum surface. The vibration of the surface of the base metal (liquid solder) correlates with the oxide film removal effect. Significant removal of the oxide film can be achieved within 2s when the amplitude of the aluminum surface is higher than 5.4 µm or when the amplitude of the liquid solder surface is higher than 10.2 µm.


Subject(s)
Aluminum/chemistry , Aluminum/radiation effects , High-Energy Shock Waves , Welding/methods , Zinc Compounds/chemistry , Materials Testing , Radiation Dosage , Vibration , Wettability/radiation effects , Zinc Compounds/analysis , Zinc Compounds/radiation effects
12.
Clin Vaccine Immunol ; 19(4): 603-8, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22357649

ABSTRACT

Intestinal epithelial cells can respond to certain bacteria by producing an array of cytokines and chemokines which are associated with host immune responses. Lactobacillus acidophilus NCFM is a characterized probiotic, originally isolated from human feces. This study aimed to test the ability of L. acidophilus NCFM to stimulate cytokine and chemokine production in intestinal epithelial cells and to elucidate the mechanisms involved in their upregulation. In experiments using intestinal epithelial cell lines and mouse models, we observed that L. acidophilus NCFM could rapidly but transiently upregulate a number of effector genes encoding cytokines and chemokines such as interleukin 1α (IL-1α), IL-1ß, CCL2, and CCL20 and that cytokines showed lower expression levels with L. acidophilus NCFM treatment than chemokines. Moreover, L. acidophilus NCFM could activate a pathogen-associated molecular pattern receptor, Toll-like receptor 2 (TLR2), in intestinal epithelial cell lines. The phosphorylation of NF-κB p65 and p38 mitogen-activated protein kinase (MAPK) in intestinal epithelial cell lines was also enhanced by L. acidophilus NCFM. Furthermore, inhibitors of NF-κB (pyrrolidine dithiocarbamate [PDTC]) and p38 MAPK (SB203580) significantly reduced cytokine and chemokine production in the intestinal epithelial cell lines stimulated by L. acidophilus NCFM, suggesting that both NF-κB and p38 MAPK signaling pathways were important for the production of cytokines and chemokines induced by L. acidophilus NCFM.


Subject(s)
Cytokines/metabolism , Epithelial Cells/immunology , Epithelial Cells/microbiology , Lactobacillus acidophilus/immunology , NF-kappa B/metabolism , Signal Transduction , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Cell Line , Gene Expression Profiling , Humans , Mice , Mice, Inbred BALB C
13.
Wei Sheng Wu Xue Bao ; 51(4): 554-60, 2011 Apr.
Article in Chinese | MEDLINE | ID: mdl-21796992

ABSTRACT

OBJECTIVE: To study the expression of immunity and inflammatory mediator factor PTX3 in intestinal epithelial cells treated with Lactobacillus acidophilus NCFM and further to reveal the regulatory mechanism. METHODS: Caco-2 cells were cocultured with Lactobacillus acidophilus NCFM for 0, 2, 4, 8, 12 h and 0, 0.5, 1, 2, 4 h respectively, then the total RNA and protein were extracted. The expression of PTX3 gene was analyzed by Real Time RT-PCR. The phosphorylation levels of NF-kappaB was analyzed by Western Blot. Caco-2 cells were pretreated with PDTC for 30 min before cocultured with Lactobacillus acidophilus NCFM for 2 h, then the total RNA was extracted and the expression of PTX3 gene was analyzed by Real Time RT-PCR. RESULTS: Lactobacillus acidophilus NCFM could induce the expression of PTX3 in Caco-2 cells. The PTX3 expression peaked at 4 h after coculture. Then its expression gradually waned out. Lactobacillus acidophilus NCFM could rapidly activate the phosphorylation of NF-kappaB, and the expression of PTX3 was decreased notably after pretreated with PDTC for 30 min. CONCLUSION: Lactobacillus acidophilus NCFM could transiently regulate the immunity and inflammatory mediator factor PTX3 expression through rapidly activating NF-kappaB signaling pathway in Caco-2 cells.


Subject(s)
C-Reactive Protein/genetics , Epithelial Cells/immunology , Lactobacillus acidophilus/physiology , Serum Amyloid P-Component/genetics , C-Reactive Protein/immunology , Caco-2 Cells , Epithelial Cells/microbiology , Gene Expression , Humans , Intestines/immunology , Intestines/microbiology , Models, Biological , NF-kappa B/genetics , NF-kappa B/immunology , Serum Amyloid P-Component/immunology
14.
Rev Sci Instrum ; 82(4): 045102, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21529034

ABSTRACT

A novel high voltage (HV) modulator that offers a short fall time to minimize sputtering effects and allow more precise control of the incident ion fluence in plasma immersion ion implantation is described. The use of 36 insulated-gate bipolar transistors in the 30 kV hard-tube pulser reduces the HV fall time to 3.5 µs, compared to a fall time of 80 µs if a pull-down resister is used. The voltage balance is achieved by a voltage-balancing resistor, clamped capacitance, and the synchronization of drive signals. Compared to the traditional method employing a pull-down resister or an additional hard tube, our design consumes less power and is more economical and reliable.

15.
Rev Sci Instrum ; 82(3): 033511, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21456741

ABSTRACT

A novel plasma immersion ion implantation technique based on high power pulsed magnetron sputtering (HPPMS) discharge that can produce a high density metal plasma is described. The metal plasma is clean and does not suffer from contamination from macroparticles, and the process can be readily scaled up for industrial production. The hardware, working principle, and operation modes are described. A matching circuit is developed to modulate the high-voltage and HPPMS pulses to enable operation under different modes such as simultaneous implantation and deposition, pure implantation, and selective implantation. To demonstrate the efficacy of the system and technique, CrN films with a smooth and dense surface without macroparticles were produced. An excellent adhesion with a critical load of 59.9 N is achieved for the pure implantation mode.

16.
Rev Sci Instrum ; 80(12): 123504, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20059142

ABSTRACT

A hybrid radio-frequency (rf)/direct-current (dc) system has been developed to control the biasing effects during deposition of diamondlike carbon (DLC) films onto the inner wall of polyethylene terephthalate (PET) bottles. An additional dc bias is coupled to the rf electrode to produce the effect of equivalent rf self-biasing. This allows more flexible control of the deposition of the DLC films which are intended to improve the gas barrier characteristics. The experimental results demonstrate that the additional dc bias improves the adhesion strength between the DLC film and PET, although the enhancement in the gas barrier properties is not significantly larger compared to the one without dc bias. The apparatus and methodology have practical importance in the food and beverage industry.

17.
Rev Sci Instrum ; 79(4): 043501, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18447526

ABSTRACT

A novel power supply system that directly couples pulsed high voltage (HV) pulses and pulsed 13.56 MHz radio frequency (rf) has been developed for plasma processes. In this system, the sample holder is connected to both the rf generator and HV modulator. The coupling circuit in the hybrid system is composed of individual matching units, low pass filters, and voltage clamping units. This ensures the safe operation of the rf system even when the HV is on. The PSPICE software is utilized to optimize the design of circuits. The system can be operated in two modes. The pulsed rf discharge may serve as either the seed plasma source for glow discharge or high-density plasma source for plasma immersion ion implantation (PIII). The pulsed high-voltage glow discharge is induced when a rf pulse with a short duration or a larger time interval between the rf and HV pulses is used. Conventional PIII can also be achieved. Experiments conducted on the new system confirm steady and safe operation.

18.
Sci China C Life Sci ; 51(4): 373-80, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18368315

ABSTRACT

We studied the genetic and epidemic characteristics of influenza A (H3N2) viruses circulated in human in Fujian Province, south of China from 1996 to 2004. Phylogenetic analysis was carried out for genes encoding hemagglutinin1 (HA1) of influenza A virus (14 new and 11 previously reported reference sequences). Our studies revealed that in the 8 flu seasons, the mutations of HA1 genes occurred from time to time, which were responsible for about four times of antigenic drift of influenza H3N2 viruses in Fujian, China. The data demonstrated that amino acid changes were limited to some key codons at or near antibody binding sites A through E on the HA1 molecule. The changes at the antibody binding site B or A or sialic acid receptor binding site 226 were critical for antigenic drift. But the antigenic sites might change and the key codons for antigenic drift might change as influenza viruses evolve. It seems important to monitor new H3 isolates for mutations in the positively selected codons of HA1 gene in south of Asia.


Subject(s)
Evolution, Molecular , Influenza A Virus, H3N2 Subtype/classification , Influenza A Virus, H3N2 Subtype/genetics , Amino Acid Sequence , China/epidemiology , Epitopes/genetics , Hemagglutinin Glycoproteins, Influenza Virus/classification , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Humans , Influenza A Virus, H3N2 Subtype/metabolism , Influenza, Human/epidemiology , Influenza, Human/virology , Molecular Sequence Data , Mutation , Seasons
19.
Rev Sci Instrum ; 78(10): 103301, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17979410

ABSTRACT

A radio frequency (rf) inductively coupled plasma apparatus has been developed to simulate the atomic oxygen environment encountered in low Earth orbit (LEO). Basing on the novel design, the apparatus can achieve stable, long lasting operation, pure and high density oxygen plasma beam. Furthermore, the effective atomic oxygen flux can be regulated. The equivalent effective atomic oxygen flux may reach (2.289-2.984) x 10(16) at.cm(2) s at an oxygen pressure of 1.5 Pa and rf power of 400 W. The equivalent atomic oxygen flux is about 100 times than that in the LEO environment. The mass loss measured from the polyimide sample changes linearly with the exposure time, while the density of the eroded holes becomes smaller. The erosion mechanism of the polymeric materials by atomic oxygen is complex and involves initial reactions at the gas-surface interface as well as steady-state material removal.


Subject(s)
Atmosphere/chemistry , Diathermy/instrumentation , Environment , Heating/instrumentation , Oxygen/chemistry , Oxygen/radiation effects , Diathermy/methods , Equipment Design , Equipment Failure Analysis , Heating/methods , Radio Waves , Reproducibility of Results , Sensitivity and Specificity , Vacuum
20.
Biomed Mater ; 2(1): 1-5, 2007 Mar.
Article in English | MEDLINE | ID: mdl-18458426

ABSTRACT

A subsonic thermal spraying technique (STS) was used to make different biocomposite coatings on titanium alloys for preparing three kinds of implants: 8Ti2G, HA and 8H2B, respectively. The implants were embedded in a region of jaw of dogs whose teeth were pulled out three months previously. The dogs, in two groups, were killed 30 days and 90 days, respectively, after they were operated on. Osteointegration between the implants and host bone was investigated by x-ray, histology and the SEM technique. The results showed that the three kinds of coatings all exhibited good biocompatibility and synostosis, but their osteointegration capability showed a difference and decreased in the sequence of 8H2B, HA and 8Ti2G. The activity of coating, which promoted the reactions between implants and bone tissue, was further increased by the addition of bioglass in the 8H2B coating. Subsequently, chemical bonding was formed, and the osteointegration strength was increased. The study provided a new approach to prepare biocomposite coatings. The 8H2B implants, which formed an integral functional biocomposite coating on Ti alloys, showed a better osteointegration capability with bioactivity and pore gradient variation. A theoretical base was provided for the biocomposite coating application.


Subject(s)
Biocompatible Materials/chemistry , Dental Implants, Single-Tooth , Titanium/chemistry , Animals , Dogs , Equipment Failure Analysis , Hot Temperature , Materials Testing , Prosthesis Design , Sonication , Surface Properties
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