Dental operative microscope has been wildly used in endodontics and operative dentistry for many years. Many progresses have been made by using operative microscope in improving the outcomes of root canal therapy, endodontic surgery and operative dentistry. However, in clinical practice, improper use of the dental operative microscope is not uncommon, the reason related to which is the operator's lack of understanding and mastering not only the properties but also the standard operative procedure of the dental operative microscope. To this end, in October 2019, the vice chairman of the Society of Cariology and Endodontology, Chinese Stomatological Association, professor Liang Jingping, organized a group of professional experts in this field, convened a meeting about the standard operative procedure of dental operative microscope. Experts at the meeting had a very heated discussion and the consensuses were reached.
China ; Consensus ; Dentistry, Operative ; standards ; Endodontics ; standards ; Humans ; Microscopy ; standards ; Root Canal Therapy

Our objective is to determine the quality of tissue engineered human skin via immunostaining, RT-PCR and electron microscopy (SEM and TEM). Culture-expanded human keratinocytes and fibroblasts were used to construct bilayer tissue-engineered skin. The in vitro skin construct was cultured for 5 days and implanted on the dorsum of athymic mice for 30 days. Immunostaining of the in vivo skin construct appeared positive for monoclonal mouse anti-human cytokeratin, anti-human involucrin and anti-human collagen type I. RT-PCR analysis revealed loss of the expression for keratin type 1, 10 and 5 and re-expression of keratin type 14, the marker for basal keratinocytes cells in normal skin. SEM showed fibroblasts proliferating in the 5 days in vitro skin. TEM of the in vivo skin construct showed an active fibrocyte cell secreting dense collagen fibrils. We have successfully constructed bilayer tissue engineered human skin that has similar features to normal human skin.
Fibroblasts/*cytology ; Keratinocytes/*cytology ; Mice, Nude ; Microscopy, Electron ; Microscopy, Electron, Scanning ; Quality Control ; Regeneration/physiology ; Skin/pathology ; Skin Transplantation/pathology ; Skin Transplantation/*standards ; Tissue Engineering/*standards

BACKGROUNDPhakic intraocular lens (pIOL) implantation has been a popular means for the treatment of high ametropia. Measurements of ciliary sulcus diameter is important for pIOL size determining. But till now, no perfect system can directly measure it. The present study was to evaluate the accuracy, repeatability and reproducibility of direct sulcus diameter measurements obtained by a full-scale 50-megahertz (MHz) ultrasound biomicroscopy (UBM).

METHODSA fresh cadaver human eye with a scale marker inserted through the posterior chamber plane from 3 o'clock to 9 o'clock meridian and 30 randomly selected eyes from 30 normal subjects were scanned by full-scale 50-MHz UBM in horizontal meridional scan plane. The distance between the scales and the whole length of the marker inside the cadaver eye were measured by the same observer using the "built-in" measurement tools and the indicating error of instrument was calculated. Reproducibility of the measurement was evaluated in 30 eyes by 2 operators using Blander and Altman plot test. Repeatability was evaluated from 10 successive eyes randomly selected from the 30 eyes by one operator.

RESULTSOn a scale of 1 mm, the greatest indicating error was 40 microm; the mean largest indicating error of 1 mm scale from the 10 images was (26 +/- 14) microm; on a scale of 11 mm, the greatest indicating error was 70 microm; the error rate was 0.64%. The mean length of the needle inside the eye of the 10 images was 11.05 mm, with the mean indicating error of 47 microm, the average error rate was 0.43%. For ciliary sulcus diameter measurements in vivo, the coefficient of variation was 0.38%; the coefficients of repeatability for intra-observer and inter-observer measurements were 1.99% and 2.55%, respectively. The limits of agreement for intra-observer and inter-observer measurement were -0.41 mm to 0.48 mm and -0.59 mm to 0.58 mm, respectively.

CONCLUSIONThe full-scale 50-MHz UBM can be a high accuracy and good repeatability means for direct measuring the ciliary sulcus diameter and useful for size determining of posterior chamber pIOL.

Ciliary Body ; diagnostic imaging ; Humans ; In Vitro Techniques ; Lenses, Intraocular ; Microscopy, Acoustic ; methods ; standards ; Reproducibility of Results

OBJECTIVETo compare the biocompatibility and osteoinductive behavior of HA (hydroxyapatite) and HA/UHMWPE (ultra-high molecular weight polyethtlene) composite in orbital implantation.

METHODSOsteoectomy of the upper orbital rim was perform on 24 adult New Zealand rabbits. The animals were randomly divided into 4 groups with 6 of each. The HA, HA/UHMWPE composite or UHMWPE (10 mm x 10 mm x 3 mm in size) was implanted to the upper orbital defect of the animal in respective group. Animals were sacrificed at 1, 4, 8, 12 weeks. Histopathologic sections of the implants were evaluated and compared with light and transmission electron microscopy study.

RESULTSDuring the experimental period of 12 weeks, there was no implant extrusion or displacement. In the groups of HA and HA/UHMWPE composite, vascular ingrowth and fibroblasts were observed shortly and osteocytes were seen at 8 weeks. Calcium deposition of the implants showed a laminar fashion at 12 weeks. In the group of UHMWPE, fibrous membranes were seen around the implant at 1 week. Transmission electron microscopy study showed that in the HA and HA/UHMWPE groups, fibroblasts and vascular ingrowth could be seen, but osteocytes were not observed.

CONCLUSIONHA/UHMWPE composite demonstrated biocompatibility and osteoinductive property. It would be a good substitute for bone, particularly for orbital bone.

Animals ; Biocompatible Materials ; pharmacology ; standards ; Bone Substitutes ; pharmacology ; standards ; Bone and Bones ; cytology ; drug effects ; ultrastructure ; Durapatite ; pharmacology ; standards ; Materials Testing ; methods ; Microscopy, Electron, Transmission ; Models, Animal ; Orbital Implants ; Osteogenesis ; drug effects ; Polyethylene ; pharmacology ; standards ; Rabbits ; Random Allocation ; Treatment Outcome

This study examined the adhesive strength of two self-adhesive methacrylate resin-based sealers (MetaSEAL and RealSeal SE) to root dentin and compared them with RealSeal and AH Plus in properties. A total of 48 extracted human single-rooted teeth were used to prepare the 0.9-mm thick longitudinal tooth slice (each per tooth). Standardized simulated canal spaces of uniform dimensions were prepared in the middle of radicular dentin. After treated with 5.25% sodium hypochlorite (NaOCl) and 17% EDTA, tooth slices were allocated randomly to four groups (n=12) in terms of different sealers used: MetaSEAL, RealSeal SE, RealSeal, and AH plus groups. The simulated canal spaces were obturated with different sealers in each group. There were 10 slabs with 20 simulated canal spaces (n=20) used in each group for push-out testing. The failure modes and the ultrastructures of fractured sealer-dentin interfaces were examined. The remaining 2 slabs in each group underwent partial demineralization for observation of the ultrastructure of resin tags. The results showed that the push-out bond strength was 12.01±4.66 MPa in MetaSEAL group, significantly higher than that in the other three groups (P<0.05). Moreover, no statistically significant differences were noted in the push-out bond strength between RealSeal SE (5.43±3.68 MPa) and AH Plus (7.34±2.83 MPa) groups and between RealSeal SE and RealSeal (2.93±1.76 MPa) groups (P>0.05). Mixed failures were predominant in the fractured sealer-dentin interfaces in MetaSEAL and AH Plus groups, while adhesive failures were frequently seen in RealSeal SE and RealSeal groups. In conclusion, after complete removal of the smear layer, MetaSEAL showed superior bond ability to root dentin. The RealSeal SE is applicable in clinical practice, with its adhesive strength similar to that of AH Plus. The self-adhesive methacrylate resin-based sealer holds promise for use in endodontic treatment.
Adhesives ; standards ; Composite Resins ; standards ; Compressive Strength ; Dental Bonding ; Dental Pulp Cavity ; ultrastructure ; Dental Stress Analysis ; methods ; Dentin ; Dentin-Bonding Agents ; standards ; Epoxy Resins ; standards ; Humans ; Materials Testing ; methods ; Methacrylates ; standards ; Microscopy, Electron, Scanning ; Root Canal Filling Materials ; standards ; Root Canal Preparation ; Tooth Root

The aim of this study was to evaluate the effect of powder-to-liquid ratio on the glass transition temperature (Tg) and the tensile properties of denture base material prepared from poly (methyl methacrylate) (PMMA) and hydroxyapatite (HA) previously treated with 3-trimethoxysilylpropyl methacrylate (gamma-MPS). Specimens for mechanical testing were prepared by adding composites powder (PMMA, BPO and HA) to the monomer (MMA and EGDMA) followed by hand mixing as in dental laboratory description usage. The glass transition temperature was studied by using differential scanning calorimetry (DSC). It was observed that the tensile properties and the Tg were affected by the powder-to-liquid ratio. The mechanical characterization of the materials were performed by using single edge notch-tension (SEN-T) specimens; the fracture toughness was slightly higher in formulation which contained HA filler compared to commercial denture base material.
Biomechanics ; Calorimetry, Differential Scanning ; *Denture Bases/standards ; *Durapatite ; *Materials Testing ; Microscopy, Electron, Scanning ; *Polymethyl Methacrylate ; Tensile Strength

This study explored epidemiological trends in trichomoniasis in Daegu, South Korea. Wet mount microscopy, PCR, and multiplex PCR were used to test for Trichomonas vaginalis in vaginal swab samples obtained from 621 women visiting 2 clinics in Daegu. Of the 621 women tested, microscopy detected T. vaginalis in 4 (0.6%) patients, PCR detected T. vaginalis in 19 (3.0%) patients, and multiplex PCR detected T. vaginalis in 12 (1.9%) patients. Testing via PCR demonstrated high sensitivity and high negative predictive value for T. vaginalis. Among the 19 women who tested positive for T. vaginalis according to PCR, 94.7% (18/19) reported vaginal signs and symptoms. Notably, more than 50% of T. vaginalis infections occurred in females younger than 30 years old, and 58% were unmarried. Multiplex PCR, which simultaneously detects pathogens from various sexually transmitted infections, revealed that 91.7% (11/12) of patients were infected with 2 or more pathogens. Mycoplasma hominis was the most prevalent co-infection pathogen with T. vaginalis, followed by Ureaplasma urealyticum and Chlamydia trachomatis. Our results indicate that PCR and multiplex PCR are the most sensitive tools for T. vaginalis diagnosis, rather than microscopy which has been routinely used to detect T. vaginalis infections in South Korea. Therefore, clinicians should take note of the high prevalence of T. vaginalis infections among adolescent and young women in order to prevent persistent infection and transmission of this disease.
Adolescent ; Adult ; Ambulatory Care Facilities/statistics & numerical data ; Female ; Humans ; Microscopy/standards ; Middle Aged ; Multiplex Polymerase Chain Reaction/standards ; Polymerase Chain Reaction/standards ; Predictive Value of Tests ; Prevalence ; Republic of Korea/epidemiology ; Sensitivity and Specificity ; Trichomonas Infections/*epidemiology/prevention & control ; Trichomonas vaginalis/physiology ; Vaginal Smears/standards ; Young Adult

OBJECTIVEIt aims to investigate the changes in composition and structure of bacterial communities developing on biological activated carbon (BAC) particles, and the bacterial functions.

METHODA pilot plant had been in service for 180 days, aiming to develop bacterial communities on activated carbon naturally. After 180 days of operation, the bacterial communities were determined by denaturing gradient gel electrophoresis (DGGE) analyses of PCR-amplified 16S rRNA genes. The study on community composition and the phylogenetic relationships of the organisms was complemented by a sequence analysis of cloned PCR products from 16S rRNA genes. Gas chromatography-mass (GC-MS) measurement was used to determine organic chemical composition of inflow and outflow water on the 300th day. TOC and NH(4)(+)-N were also tested in this experiment.

RESULTSIt showed that the stable bacterial structure did not develop on BAC particles until the 9th month during running time of the BAC filter. The communities were finally dominated by Pseudomonas sp., Ba-cillus sp., Nitrospira sp., and an uncultured bacterium. Stable bacterial communities played an important role in removal of NH(4)(+)-N and total organic carbon (TOC). Results from gas chromatography-mass (GC-MS) showed that 36 kinds of chemicals in feed water were eliminated, and concentrations of 5 kinds of chemicals decreased. These chemicals served as nutrients for the dominant bacteria.

CONCLUSIONThe findings from the study suggested that the stability of microbial structure was beneficial for improving NH(4)(+)-N and TOC removal efficiencies. The dominant bacteria had the advantage of biode-grading a wide range of organic chemicals and NH(4)(+)-N.

Ammonia ; chemistry ; Bacteria ; classification ; genetics ; Biofilms ; Carbon ; chemistry ; Filtration ; instrumentation ; methods ; Microscopy, Electron, Scanning ; Pilot Projects ; Waste Disposal, Fluid ; instrumentation ; methods ; Water Microbiology ; Water Purification ; instrumentation ; methods ; Water Supply ; standards

Genes encoding for the premembrane and envelope (prME), envelope (E) and nonstructural protein (NS1) of Japanese encephalitis virus (JEV) were cloned. Each protein was expressed in baculovirus expression system. Of the three proteins expressed in baculovirus system, only prME had hemagglutination activity. The prME (72 and 54 kDa), E (54 kDa) and NS1 (46 kDa) proteins could be detected by Western blotting in the recombinant virus infected cells. Immunogenicity of the recombinant proteins obtained from infected Spodoptera frugiperda (Sf-9) cells was examined in mice. The 3 week-old ICR mice immunized intraperitoneally with three recombinant proteins three times were challenged with a lethal JEV. A survival rate was increased from about 7.7% in unimmunized mice to 92.3% in E + prME and only E groups. The complete protection was shown in prME and live vaccine inoculated groups, respectively. We also measured neutralizing antibody and three immunoglobulin subtypes of IgG1, IgG2a and IgG2b in the sera of mice before and after challenge. Titers of IgG1 antibodies were approximately two to three times higher than that of IgG2b antibodies in all the immunized groups as compared to the control group. However, IgG2a antibody level somewhat increased after challenge, indicating T-helper type 1 (Th1) cell response. The results of this study can provide useful information for developing efficacious subunit vaccine against JEV.
Animals ; Antibodies, Viral/blood ; Baculoviridae/genetics ; Blotting, Western ; Cloning, Molecular ; Encephalitis Virus, Japanese/genetics/*immunology ; Encephalitis, Japanese/*immunology/prevention&control ; Female ; Immunization ; Immunoglobulin Isotypes/blood ; Japanese Encephalitis Vaccines/*immunology/standards ; Mice ; Mice, Inbred ICR ; Microscopy, Fluorescence ; Plasmids ; Recombinant Proteins/genetics/immunology ; Viral Envelope Proteins/genetics/*immunology ; Viral Matrix Proteins/genetics/*immunology ; Viral Nonstructural Proteins/genetics/*immunology

Microsatellite instability (MSI) which resulted from the deficiency of DNA mismatch repair (MMR), is an important clinical significance in the related solid tumors, such as colorectal cancer and endometrial cancer. There are several methods to detect MSI status, including immunohistochemistry for MMR protein, multiplex fluorescent polymerase chain reaction (PCR) for microsatellite site and MSI algorithm based on next generation sequencing (NGS). The consensus elaborates the definition and clinical significance of MSI as well as the advantages and disadvantages of the three detection methods. Through this expert consensus, we hope to promote the screening which based on MSI status in malignant tumors and improve the acknowledge of clinicians about various testing methods. Thereby, they could interpret the results more accurately and provide better clinical services to patients.
Antineoplastic Agents ; administration & dosage ; adverse effects ; therapeutic use ; China ; Colorectal Neoplasms ; genetics ; pathology ; Consensus ; DNA Mismatch Repair ; DNA Sequence, Unstable ; Delivery of Health Care ; standards ; Endometrial Neoplasms ; Female ; Humans ; Immunohistochemistry ; Microsatellite Instability ; Microsatellite Repeats ; Microscopy, Fluorescence ; Polymerase Chain Reaction ; Practice Guidelines as Topic