BACKGROUND AND OBJECTIVE

Endocrine Disrupting Chemicals (EDCs) are ubiquitously found as low-level contaminants and pose serious threat to women’s health. EDCs may result in various reproductive disorders, fetal birth and developmental abnormalities, and endocrine and metabolic disorders. EDCs can be detected in body fluids of exposed individuals including blood and urine. This study aimed to detect four EDCs — Methyl Paraben (MP), 2,4-Dichlorophenoxyacetic acid (2,4-D), Monobutyl Phthalate (MBP), and Bisphenol A (BPA) in urine samples of women using Ultra-Performance Liquid Chromatography – Quadrupole Time-of-Flight (UPLC-QTOF) mass spectrometry.

METHODS

Sequential steps of enzymatic deconjugation, liquid-liquid extraction, solid phase extraction, and liquid chromatography separation and mass spectrometry detection were optimized in urine samples. The method was used to analyze 70 urine samples from women of reproductive age.

RESULTS

The sample preparation method showed a recovery ranging from 86.6% (MBP) to 100 % (2,4-D). The method demonstrated limits of quantitation ranging from 1.52 ng/m(MP) to 6.46 ng/mL(2,4D). Intra-day precisions expressed as relative standard deviation were all below 15% while accuracy was shown to range from 67.10% (2,4-D) to 102.39% (MBP). MP was detected in nine samples (12.86%) with a geometric mean value of 10.15 ng/ml (range: 3.62-52.39 ng/ml). MBP was detected in 68 samples (97.14%) with a geometric mean value of 97.62 ng/ml (range: 15.32-698.18 ng/ml). BPA was detected only once (9.58 ng/ml) while 2, 4-D was not detected in all samples.

CONCLUSION

A UPLC-QTOF mass spectrometry method to detect four EDCs at parts per billion level (ng/ml) was adapted and applied for analysis of urine samples. This method can find applicability in routine testing of clinical specimens as well as surveillance and other epidemiological studies.

Endocrine Disruptors ; 2,4-dichlorophenoxyacetic Acid ; Bisphenol A

Bisphenol A (BPA) is a kind of exogenous chemicals presenting in the human living environment widely which affects the action of endocrine hormones in the human body. Numerous studies have shown that BPA has reproductive toxicity in the spermatogenic function damage of the testes through a variety of mechanisms such as interfering with endocrine function, inducing oxidative stress, promoting spermatogonial cell apoptosis, destroying the integrity of the blood-testis barrier, and regulating epigenetic inheritance, thereby destroying male fertility. Relevant studies have shown that TCM can improve male fertility by reversing BPA-induced reproductive damage through multi-component, multi-target and multi-mechanisms. However, there is no systematic review on the mechanism of TCM to reduce the reproductive toxicity of BPA. Based on the existing studies, this article will systematically introduce the mechanisms of BPA-induced reproductive impairment in men and the progress of TCM interventions, with a view to providing reference targets and research directions for the development of new Chinese medicines.
Humans ; Benzhydryl Compounds/adverse effects* ; Male ; Phenols/adverse effects* ; Medicine, Chinese Traditional ; Infertility, Male/chemically induced* ; Testis/drug effects* ; Drugs, Chinese Herbal/therapeutic use* ; Bisphenol A Compounds

Prostate cancer is one of the most common tumor, with the disease progressing from inert to aggressive tumors, and rapidly progressing to castration-resistant prostate cancer. Early-stage prostate cancer is usually asymptomatic. And by the time that symptoms appear, the disease has progressed to an incurable stage. Therefore, early diagnosis and treatment is especially important to control prostate cancer, which prolongs the survival period of patients. Digital rectal examination and prostate-specific antigen have been widely used in the diagnosis of prostate cancer. However, there are certain limitations that lead to overdiagnosis and overtreatment. Although prostate needle biopsy is still the gold standard for diagnosing prostate cancer, with the wide application of multiparametric magnetic resonance examination and PSMA-PET/CT and other technologies in recent years, as well as the emergence of new biomarkers with higher sensitivity and specificity, its status as the gold standard has been challenged. And the diagnostic mode of prostate cancer has also undergone great changes. On this basis, the radical prostatectomy without prostate needle biopsy has been attempted clinically to treat prostate cancer, which gains the good clinical results. This article provides a review of the latest research advances in early screening and diagnostic models for prostate cancer.
Humans ; Male ; Benzhydryl Compounds/adverse effects* ; Drugs, Chinese Herbal/therapeutic use* ; Infertility, Male/chemically induced* ; Medicine, Chinese Traditional ; Phenols/adverse effects* ; Testis/drug effects* ; Bisphenol A Compounds

The purpose of this study was to evaluate the color stability of light cured composite resins according to the resin matrices. Three kinds of resin matrices such as Bis-GMA (Venus® Diamond; VD), Silorane (FiltekTM P90; P90), and Ormocer (Admira; Ad) were selected. Each of them were used to prepare 30 specimens. The initial CIE L*a*b* values were measured by means of a Spectrophotometer (NF999, Nippon Denshoku, Japan). For accelerated aging process, the specimens were immersed in a circulating water bath with distilled water at 60℃. Spectrophotometric analyses were made after immersion of 8, 16, 24, 41 days and the color difference (ΔE*) was calculated. The L* value increased compared with initial L* value. VD had the greatest L* value change and Ad had the smallest L* value change (p<0.05). Ad had the greatest a* value change and VD had the smallest a* value change (p<0.05). The b* value of P90 increased steadily in positive value (+)(p<0.05). ΔE* of Ad had the smallest value and that of P90 had the greatest change with time. According to this study, the value of light cured composite resins was increased with water sorption and color of those changed into greenish and yellowish. And according to the evaluation of color stability, Ad with Ormocer as resin matrices had the best color stability with time in oral environment and P90 with Silorane as resin matrices had the lowest color stability with time. And VD had the greatest initial ΔE*.
Aging ; Baths ; Bisphenol A-Glycidyl Methacrylate ; Composite Resins ; Diamond ; Immersion ; Organically Modified Ceramics ; Silorane Resins ; Water

Continuing advances in dentin bonding technology and adhesives revolutionized bonding of resin-based composite restorations. However, hybrid layers created by contemporary dentin adhesives present imperfect durability, and degradation of collagen matrix by endogenous enzymes is a significant factor causing destruction of hybrid layers. Bond durability can be improved by using enzyme inhibitors to prevent collagen degradation and to preserve integrity of collagen matrix. This review summarizes progress on matrix metalloproteinase inhibitors (including chlorhexidine, ethylenediaminetetraacetic acid, quaternary ammonium salt, tetracycline and its derivatives, hydroxamic acid inhibitors, bisphosphonate derivative, and cross-linking agents) and suggests prospects for these compounds.
Acid Etching, Dental ; Bisphenol A-Glycidyl Methacrylate ; Collagen ; Dental Bonding ; Dentin ; Dentin-Bonding Agents ; Humans ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase Inhibitors

OBJECTIVEThis study aims to compare the marginal accuracy of single crowns fabricated using self-curing resin, Luxatemp, and computer aided design/computer aided manufacturing (CAD/CAM) methods in clinical application.

METHODSA total of 30 working dies, which were obtained from 30 clinical teeth prepared with full crown as standard, were created and made into 30 self-curing resin, Luxatemp, and CAD/CAM single crowns. The restorations were seated on the working dies, and stereomicroscope was used to observe and measure the thickness of reference points. One-way analysis of variance, which was performed using SPSS 19.0 software package, compared the marginal gap widths of self-curing resin, Luxatemp, and CAD/CAM provisional crowns.

RESULTSThe mean marginal gap widths of the fabricated self-curing resin, Luxatemp, and CAD/CAM were (179.06±33.24), (88.83±9.56), and (43.61±7.27) μm, respectively. A significant difference was observed among the three provisional crowns (P<0.05).

CONCLUSIONSThe marginal gap width of CAD/CAM provisional crown was lower than that of the self-curing resin and Luxatemp. Thus, the CAD/CAM provisional crown offers a better remediation effect in clinical application.

Bisphenol A-Glycidyl Methacrylate ; Computer-Aided Design ; Crowns ; Dental Prosthesis Design ; Humans

OBJECTIVEThis study investigated the shear bond strength and the ability of resin adhesive containing different amounts of bioactive glass (BG) to prevent dentin demineralization.

METHODSBG bonds at 30%, 40%, and 50% concentrations comprised a mixture of coupling agents modifying BG and Single Bond 2. Forty permanent premolars extracted for orthodontic treatment were randomly divided into four groups, namely, control group (BG-free), 30% BG group, 40% BG group, and 50% BG group. Composite resin and dentin were prepared into bonding specimens by using respective adhesives and then immersed in artificial saliva at pH 4 for 1 week. Changes in the pH values of the solution were measured every 24 h. The microtensile bond strength (TBS) of each specimen was examined after immersion in distilled water at 37 °C for 24 h.

RESULTSThe TBS values of the control group, 30% BG group, 40% BG group, and 50% BG group were (27.76±0.29), (27.05±0.58), (26.95±0.69), and (25.12±0.24) MPa, respectively. The TBS of the control group was not significantly different from that of the 30% BG group (P=0.06) but significantly higher than that of the 40% BG and 50% BG groups (P=0.04 and P=0.00, respectively). In addition, TBS was significantly higher in the 30% BG and 40% BG groups than in the 50% BG group (P=
0.00 and P=0.00, respectively). The pH values of the solution increased with increasing BG content.

CONCLUSIONSBG bonds are useful in the prevention of dentin demineralization. However, in this study, the 30% BG group did not affect the short-term bond strength. The 50% BG group displayed the optimum ability to inhibit demineralization but showed the worst bond strength.

Adhesives ; Bisphenol A-Glycidyl Methacrylate ; Composite Resins ; Dental Bonding ; Dentin ; Glass ; Humans ; Materials Testing ; Saliva, Artificial ; Tensile Strength ; Tooth Demineralization

PURPOSE: Bonding agents (BA) are the crucial weak link of composite restorations. Since the commercial materials' compositions are not disclosed, studies to formulize the optimum ratios of different components are of value. The aim of this study was to find a proper formula of BAs. MATERIALS AND METHODS: This explorative experimental in vitro study was composed of 4 different sets of extensive experiments. A commercial BA and 7 experimental formulas were compared in terms of degree of conversion (5 experimental formulas), shear bond strength, mode of failure, and microleakage (3 experimental formulas). Statistical analyses were performed (alpha=.05). The DC of selected formula was tested one year later. RESULTS: The two-way ANOVA indicated a significant difference between the shear bond strength (SBS) of two tissues (dentin vs. enamel, P=.0001) in a way that dentinal bonds were weaker. However, there was no difference between the four materials (P=.283). The adhesive mode of failure was predominant in all groups. No differences between the microleakage of the four materials at occlusal (P=.788) or gingival (P=.508) sites were detected (Kruskal-Wallis). The Mann-Whitney U test showed a significant difference between the microleakage of all materials (3 experimental formulas and a commercial material) together at the occlusal site versus the gingival site (P=.041). CONCLUSION: A formula with 62% bisphenol A-glycidyl methacrylate (Bis-GMA), 37% hydroxy ethyl methacrylate (HEMA), 0.3% camphorquinone (CQ), and 0.7% dimethyl-para-toluidine (DMPT) seems a proper formula for mass production. The microleakage and SBS might be respectively higher and lower on dentin compared to enamel.
Adhesives ; Bisphenol A-Glycidyl Methacrylate ; Dental Enamel ; Dentin* ; Dentin-Bonding Agents ; Polymerization* ; Polymers* ; Tooth*

OBJECTIVETo study the types of matrix metalloproteinases (MMPs) involved in dentin bonding interface degradation.

METHODSDentin slices were prepared and treated with two adhesive systems (Single Bond 2 or Clearfil S3 Bond). The dentin surface was bonded with composite resin. All specimens were immersed in sterile artificial saliva for 0 or 6 months, and their micro-shear bond strength (muSBS) were measured. The fracture modes were observed through field emission scanning electron microscope (FE-SEM). Dentin slices with 4 mm x 3 mm x 1 mm dimensions were prepared. The slices were divided into three groups according to the treatment modes (negative control, Single Bond 2, and Clearfil S3 Bond). All specimens were stored in sterile artificial saliva for 0 or 6 months. The concentrations of MMP-1, -2, -3, -8, and -9 of each group were detected through fluorescent microsphere immunoassay.

RESULTSThe muSBS of both adhesive systems significantly decreased after storage aging. Significant differences in failure modes within the four groups tested in this study were observed. Compared with the negative control, the concentrations of MMP-1 and MMP-3 in different adhesive groups showed no significant difference after storage aging. However, the concentrations of MMP-2, -8, and -9 in Single Bond 2 group and the concentrations of MMP-8 and -9 in Clearfil S3 Bond group significantly decreased after 6 months of storage aging.

CONCLUSIONSignificant degradation occur in the dentin bonding interface of both adhesive groups under 6 months aging challenge. The concentrations ofdentinal MMP-2, -8, and -9 significantly decrease after treatment with adhesives and aging, indicating that these MMPs have an important function in dentin bonding interface degradation.

Bisphenol A-Glycidyl Methacrylate ; Composite Resins ; Dental Bonding ; Dentin ; Dentin-Bonding Agents ; Materials Testing ; Matrix Metalloproteinases ; Resin Cements ; Surface Properties

Teeth that have short clinical crown, which are not alone enough to support the definitive restoration can be best treated using the post and core system. The advantages of fiber post over conventional metallic post materials have led to its wide acceptance. In addition to that the combination of aesthetic and mechanical benefits of fiber post has provided it with a rise in the field of dentistry. Also the results obtained from some clinical trials have encouraged the clinicians to use the fiber posts confidently. Fiber posts are manufactured from pre-stretched fibers impregnated within a resin matrix. The fibers could that be of carbon, glass/silica, and quartz, whereas Epoxy and bis-GMA are the most widely used resin bases. But recently studies are also found to be going on for polyimide as possible material for the fiber post resin base as a substitute for the conventional materials.
Bisphenol A-Glycidyl Methacrylate ; Carbon ; Crowns ; Dentin ; Dentistry ; Quartz ; Tooth