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In response to the increasing number of carbapenem-resistant Enterobacterales (CRE), we investigated carbapenemase-producing Klebsiella pneumoniae and non-K. pneumoniae epidemiology and genetics. We collected 76 clinical Enterobacterales and 4 stool surveillance Escherichia coli isolates resistant to ertapenem or imipenem. Using polymerase chain reaction (PCR) and DNA sequencing, we assessed carbapenemases, extended-spectrum β-lactamases, and AmpC β-lactamases. Molecular typing via pulsed-field gel electrophoresis (PFGE) and conjugation experiments were conducted to examine resistance gene transfer. Among the 80 isolates, 96.2% harbored at least one carbapenemase gene, with bla OXA-48 in 87.5%. KPC-2 and IMP-8 carbapenemases were found in 15.0 and 22.5% of the isolates, respectively, with 27.5% having 2 or more carbapenemase genes. The PFGE analysis revealed the presence of diverse genotypes. PCR-based plasmid replicon typing identified IncA/C as the most prevalent type among K. pneumoniae isolates (26/29), and IncF and IncFIB among E. coli isolates (22/28). Conjugal transfer was successful for plasmids encoding OXA-48, CTX-M-3, CTX-M-14, CMY-2, and other β-lactamases, except the KPC-2 gene. In conclusion, our study highlights high carbapenemase prevalence in CRE, primarily OXA-48. Multiple carbapenemases within strains were common, and PFGE showed diverse patterns in these carbapenem-resistant isolates.

Background/purpose: The separation of dentistry and medicine was initiated as a historical root. The purpose of this study was to evaluate the implication of integrating pediatric education into a pediatric dentistry course (so-called the integrated pediatric dentistry course in this study) for undergraduate dental students through students' perspectives., Materials and Methods: A total of the 34 fifth-year dental students were invited to fill out the questionnaire for the integrated pediatric dentistry course survey after the class of integrated pediatric dentistry course., Results: Of the 34 dental students, all participated in the survey with a 100% valid response rate. The results showed that most of dental students found this integrated pediatric dentistry course to be helpful in improving their knowledge and clinical skills for pediatric dentistry, and knowledge about pediatrics related to dentistry. However, in comparison, the acquisition of clinical skills was less than that of knowledge for pediatric dentistry., Conclusion: We conclude that the integrated pediatric dentistry course improves dental students' knowledge and clinical skills about pediatric dentistry, and knowledge about pediatrics related to dentistry. Considering the effectiveness of this integrated pediatric dentistry course on students' knowledge and clinical skills, and positive attitude towards pediatric dentistry, this model shows promising for the further use in the dental education., Competing Interests: The authors have no conflicts of interest relevant to this article., (© 2023 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V.)

Extracellular vesicles (EVs) are small, lipid bilayer-enclosed structures released by various cell types that play a critical role in intercellular communication. In atherosclerosis, EVs have been implicated in multiple pathophysiological processes, including endothelial dysfunction, inflammation, and thrombosis. This review provides an up-to-date overview of our current understanding of the roles of EVs in atherosclerosis, emphasizing their potential as diagnostic biomarkers and their roles in disease pathogenesis. We discuss the different types of EVs involved in atherosclerosis, the diverse cargoes they carry, their mechanisms of action, and the various methods employed for their isolation and analysis. Moreover, we underscore the importance of using relevant animal models and human samples to elucidate the role of EVs in disease pathogenesis. Overall, this review consolidates our current knowledge of EVs in atherosclerosis and highlights their potential as promising targets for disease diagnosis and therapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Patel, Guo, Abdul Samad and Howe.)

The identification of additional Echinococcus granulosus sensu lato (s.l.) complex species/genotypes in recent years raises the possibility that there might be more variation among this species in China than is currently understood. The aim of this study was to explore intra- and inter-species variation and population structure of Echinococcus species isolated from sheep in three areas of Western China. Of the isolates, 317, 322, and 326 were successfully amplified and sequenced for cox1, nad1, and nad5 genes, respectively. BLAST analysis revealed that the majority of the isolates were E. granulosus s.s., and using the cox1, nad1, and nad5 genes, respectively, 17, 14, and 11 isolates corresponded to Elodea canadensis (genotype G6/G7). In the three study areas, G1 genotypes were the most prevalent. There were 233 mutation sites along with 129 parsimony informative sites. A transition/transversion ratio of 7.5, 8, and 3.25, respectively, for cox1, nad1, and nad5 genes was obtained. Every mitochondrial gene had intraspecific variations, which were represented in a star-like network with a major haplotype with observable mutations from other distant and minor haplotypes. The Tajima's D value was significantly negative in all populations, indicating a substantial divergence from neutrality and supporting the demographic expansion of E. granulosus s.s. in the study areas. The phylogeny inferred by the maximum likelihood (ML) method using nucleotide sequences of cox1-nad1-nad5 further confirmed their identity. The nodes assigned to the G1, G3, and G6 clades as well as the reference sequences utilized had maximal posterior probability values (1.00). In conclusion, our study confirms the existence of a significant major haplotype of E. granulosus s.s. where G1 is the predominant genotype causing of CE in both livestock and humans in China., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Intervertebral disc degeneration (IDD) is the most common cause of low-back pain. Accumulating evidence indicates that the expression profiling of noncoding RNAs (ncRNAs), including microRNAs (miRNAs), circular RNAs (circRNAs), and long noncoding RNAs (lncRNAs), are different between intervertebral disc tissues obtained from healthy individuals and patients with IDD. However, the roles of ncRNAs in IDD are still unclear until now. In this review, we summarize the studies concerning ncRNA interactions and regulatory functions in IDD. Apoptosis, aberrant proliferation, extracellular matrix degradation, and inflammatory abnormality are tetrad fundamental pathologic phenotypes in IDD. We demonstrated that ncRNAs are playing vital roles in apoptosis, proliferation, ECM degeneration, and inflammation process of IDD. The ncRNAs participate in underlying mechanisms of IDD in different ways. MiRNAs downregulate target genes' expression by directly binding to the 3'-untranslated region of mRNAs. CircRNAs and lncRNAs act as sponges or competing endogenous RNAs by competitively binding to miRNAs and regulating the expression of mRNAs. The lncRNAs, circRNAs, miRNAs, and mRNAs widely crosstalk and form complex regulatory networks in the degenerative processes. The current review presents novel insights into the pathogenesis of IDD and potentially sheds light on the therapeutics in the future.

Purpose: Intermittent hypoxia is a characteristic pathological change in obstructive sleep apnoea (OSA) that can initiate oxidative stress reaction and pro-inflammatory cytokine release. The purpose of this study was to assess the effect and protective mechanism of Astragaloside IV (AS-IV) in intermittent hypoxia-induced human lung epithelial Beas-2B cells., Methods: Human lung epithelial Beas-2B cells were exposed to intermittent hypoxia or normoxia in the absence or presence of AS-IV. MTT assay was performed to determine the cell viability. The levels of reactive oxygen species (ROS), lactate dehydrogenase (LDH), malonaldehyde (MDA), and superoxide dismutase (SOD) were measured to evaluate oxidative stress. The levels of cytokines interleukin (IL)-8, IL-1β, and IL-6 were evaluated by enzyme-linked immunosorbent assay and real-time PCR. The expression of Toll-like receptor 4 (TLR4), mitogen-activated protein kinase (MAPK), and nuclear transcription factor-kappa B (NF-κB) signalling pathways was analysed by western blot., Results: The results showed that AS-IV significantly reduced the levels of ROS, LDH, MDA, IL-8, IL-1β, and IL-6, and increased the level of SOD in intermittent hypoxia-induced Beas-2B cells. It also suppressed the phosphorylation of MAPKs, including P38, c-Jun N-terminal kinase and extracellular signal-regulated kinase, and inhibited the activation of the NF-κB signalling pathway by reducing the phosphorylation of IκBα and p65., Conclusions: AS-IV attenuates inflammation and oxidative stress by inhibiting TLR4-mediated MAPK/NF-κB signalling pathways in intermittent hypoxia-induced Beas-2B cells.

Carbapenemase-producing combined porin loss is one of the primary mechanisms for carbapenem resistance. Although mutations in ompK35 and ompK36 genes have often been identified in carbapenem-resistant Klebsiella pneumoniae , reports on the porin protein gene disruption by insertion sequence (IS) elements are varied. The ompK36 porin protein gene disruption by IS elements and OmpK36 production loss in six bla KPC-2 -carrying K. pneumoniae isolates were detected in this study. IS 903 , IS Ec68, and IS 1 insertions were noted in the 3, 2, and 1 isolates, respectively. The six K. pneumoniae isolates showed five different pulsed-field gel electrophoresis patterns and belonged to four multilocus sequence typing types, ST4, ST11, ST15, and ST39. This study increases our understanding of the genetic background of KPC-2 carbapenemases in porin-defective clinical isolates and the contribution of OmpK36 production loss to carbapenem resistance.

A clinical isolate of Citrobacter freundii (JA99) obtained from a bile culture of a Taiwanese patient was found to produce a plasmid-encoded β-lactamase conferring resistance to oxyimino-cephalosporins and cephamycins. Resistance arising from production of the β-lactamase could be transferred by conjugation with an IncW plasmid (pJA99) into Escherichia coli J53. The substrate and inhibition profiles of this enzyme resembled that of an AmpC β-lactamase. The resistance gene of pJA99, cloned and expressed in E. coli DH5α, was shown to contain an open reading frame showing 92% amino acid identity with the plasmid-encoded enzyme CFE-1 of E. coli KU6400. DNA sequence analysis also identified a gene upstream of ampC in pJA99 whose sequence was 95.0% identical to the ampR gene from E. coli KU6400. In addition, orf1, the fumarate operon (frdABCD), blc, lolB and repB surrounding the ampR-ampC genes in C. freundii were identified. This DNA fragment was absent in other Citrobacter spp. Therefore, we describe a new plasmid-encoded AmpC β-lactamase, named CFE-2. This study highlights the emergence of broad-spectrum cephalosporin resistance in C. freundii owing to a new type of AmpC β-lactamase., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Purpose. Carbapenem-resistant Klebsiella pneumoniae (CRKP) has emerged as a major challenge for global healthcare systems. The objectives of this study were to determine the nosocomial spread of CRKP clones and analyse the molecular characteristics of CRKP in our hospital. Methodology. Ninety-eight non-duplicated clinical CRKP isolates were collected from March 2014-June 2015. Clinical, demographic and microbiological data of patients with CRKP were reviewed. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing were applied to investigate the genetic relationship between the 98 isolates. Antibiotic resistance genes were identified by conventional PCR-sequencing. Results. PFGE patterns were grouped into 26 clusters. Two main PFGE clusters were identified: L (53 isolates, belonging to ST11) and N (11 isolates, belonging to ST11). The most dominant ST was ST11 (79 %, 77/98), followed by ST273 (5 %, 5/98). KPC-2 ( n =82) was the predominant carbapenemase followed by OXA-48 ( n =64). Fifty isolates (51 %, 50/98) harboured bla KPC-2 and bla OXA-48 simultaneously, and three of these isolates were detected with the third carbapenemase genes ( bla IMP-8 or bla VIM-1 ). Conclusion. The clonal spread of K. pneumoniae ST11 expressing OXA-48, KPC-2 and CTX-M-14 β-lactamases was the cause of an outbreak of CRKP. To the best of our knowledge, a single strain harbouring A-, B- and D-class carbapenemase genes has not previously been identified. There is a high prevalence of plasmid-encoded KPC-2- and OXA-48-producing CRKP in our hospital; most isolates were members of ST11, which may be representative of a high-risk CRKP clone disseminating in central Taiwan.

Objective: To investigate the effect of preventing perivascular adhesion with topical application of sodium hyaluronate on intimal hyperplasia of the vein grafts in rabbits. Methods: Twenty-four male New Zealand white rabbits, aged 5 months, were randomly divided into 2 groups: Group A and B ( n =12 rabbits per group). Artery defect model was established by cutting about 1 cm artery from the middle part of the dissociated left common carotid artery. A section about 3 cm was cut from the right external jugular vein, and the harvested vein was inverted and end-to-end anastomosed to the artery defect. After anastomosis, the adventitia and two anastomosis of the grafted veins in group A was applied 0.2 ml sodium hyaluronate locally to, and corresponding site in Group B was served as a control, but with the sterile normal saline. The grafted veins were obtained 1, 2 and 4 weeks after operation, HE staining and Masson staining were preformed for histological changes of grafted vein wall, proliferating cell nuclear antigen (PCNA) and platelet-derived growth factor (PDGF) immunohistochemistry staining were conducted for proliferation and expression and distribution of PDGF of the grafted vein. Results: The macroscopic and histological observation showed that the perivascular adhesions in Group A were looser when compared with those in Group B. The thickness of the intima, the degree of intima hyperplasia of 2 groups at different time points were as follows: at 1 week after operation, group A[(25.5±3.9) μm, (1.2±0.1) ]and group B[(26.2±4.2)μm, (1.2±0.1)]; at 2 weeks after operation, group A[(44.3±2.5)μm, (1.2±0.1)]and group B[(51.0±3.8)μm, (1.4±0.0)]; at 4 weeks after operation, group A[(69.9±6.8)μm, (1.5±0.1)] and group B[(84.4±6.4)μm, (1.7±0.1)]. Group A was inferior to group B in terms of the above three parameters 2 and 4weeks after operation ( P <0.05). Cell proliferation index of intima and that of media were as follows: at 1 week after operation, group A (7.4±2.2), (21.5±3.2) and group B (11.5±2.0), (28.6±4.5); at 2 weeks, group A (20.0±3.2), (35.8±3.4) and group B (26.8±4.1), ( 42.6±4.2); at 4 weeks, group A (11.4±2.0), (22.1±2.7) and group B (15.5±2.4, 28.6±3.9). Group A was inferior to group B in terms of cell proliferation index of intima and media 1, 2 and 4 weeks after operation ( P <0.05). The percentage of PDGF-positive cells of intima, media and adventitia was as follows: at 1 week after operation, group A (7.7±1.6), (19.6±3.7), (2.5±1.5) and group B (7.6±2.4), (20.6±4.4), (10.3±2.3); at 2 weeks after operation, group A (11.4±2.6), (19.8±3.1), (12.9±3.3) and group B (19.5±3.5), ( 30.6±5.2), (30.5±5.8); at 4 weeks after operation, group A (6.2±1.9), ( 11.1±2.8), (10.2±2.4) and group B (10.5±2.0), (18.6±3.2), (26.5±3.8). Group A was inferior to group B in terms of the percentage of PDGF-positive cells of intima, media and adventitia 2 and 4 weeks after operation ( P <0.05) and Group A was inferior to group B that of adventitia 1 week after operation ( P <0.05). Conclusion: Preventing perivascular adhesion with topical application of sodium hyaluronate can inhibit intimal hyperplasia.

Two parallel biological aerated filters (BAF)-ozonation,named as number 1(feeding with FeSO 4 ·7H 2 O) and number 2,were used to treat petrochemical secondary effluent.The effect of FeSO 4 ·7H 2 O on COD and phosphorus removal by BAF-ozonation was studied.Molecular weight distribution,three-dimensional fluorescence scan and gas chromatography-mass spectrometry (GC-MS) were used to analyze water quality before and after BAF-ozonation.The results showed the average COD and TP concentrations were 82.91 mg·L -1 and 1.37 mg·L -1 ,respectively.When the dosage of FeSO 4 ·7H 2 O was 9 mg·L -1 ,the average removal rates of COD and TP were 52.20% and 71.50%,respectively.The average COD removal rate in number 1 combined process was 17.15%,which was higher than that in number 2 combined process.The TP removal rate in number 1 combined process was increased by 51.81%.The percentage of dissolved organic matters with relative molecular weight less than 1×10 3 was 52% in the raw wastewater.However,the percentage increased to 75% when treated by number 1 combined process and the removal rate of various molecular weight organics was increased.Three-dimensional fluorescence analysis showed that the dosage of FeSO 4 ·7H 2 O could improve the removal of fluorescent substances.GC-MS results showed that the number and concentration of organics were reduced after number 1 combined process in comparison with number 2 combined process.BAF-ozone could be enhanced by FeSO 4 ·7H 2 O when treating petrochemical secondary effluent.

Introduction: Transforming growth factor β1 (TGF-β1) plays an important role in cell proliferation, matrix formation, and odontogenesis. This study investigated the effects of TGF-β1 on stem cells from apical papilla (SCAPs) and its signaling by MEK/ERK and Smad2., Methods: SCAPs were exposed to TGF-β1 with/without pretreatment and coincubation by SB431542 (an ALK5/Smad 2/3 inhibitor) or U0126 (a MEK/ERK inhibitor). Cell growth was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide assay or direct counting of viable cells. Collagen content was determined by using the Sircol collagen assay (Biocolor Ltd, Newtownabbey, Northern Ireland). Cell differentiation was evaluated by measuring alkaline phosphatase (ALP) activity. Smad2 and ERK1/2 phosphorylation was analyzed by Western blotting or PathScan phospho-enzyme-linked immunosorbent assay (Cell Signaling Technology Inc, Danvers, MA)., Results: TGF-β1 stimulated the growth and collagen content of cultured SCAPs. TGF-β1 stimulated ERK1/2 and Smad2 phosphorylation within 60 minutes of exposure. Pretreatment by U0126 and SB431542 effectively prevented the TGF-β1-induced cell growth and collagen content in SCAPs. TGF-β1 stimulated ALP activity at lower concentrations (0.1-1 ng/mL) but down-regulated ALP at higher concentrations (>5 ng/mL). U0126 prevented 0.5 ng/mL TGF-β1-induced ALP activity but showed little effect on 10 ng/mL TGF-β1-induced decline of ALP in SCAPs. Interestingly, SB431542 attenuated both the stimulatory and inhibitory effects on ALP by TGF-β1., Conclusions: TGF-β1 may affect the proliferation, collagen turnover, and differentiation of SCAPs via differential activation of ALK5/Smad2 and MEK/ERK signaling. These results highlight the future use of TGF-β1 and SCAP for engineering of pulpal regeneration and apexogenesis., (Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: To explore the relationship between the causes and length of posterior malleolar fragment and treatment strategies of adult patients with three types of ankle joint injury., Methods: The investigators recruited 233 cases of type C injury, 35 cases of type B injury and 91 cases of type A injury. Type A injury referred to simple ankle joint fracture with the involvement of posterior malleolar fragment. Type B injury tibial shaft fracture with ipsilateral ankle joint fracture. And posterior malleolar fracture line was the continuity of tibial shaft fracture line. Type C injury appeared similar to Type B injury, but tibial and malleolar fracture lines were not continued. The ratio between the length of posterior malleolar articular and the total length of articular surface was calculated in theses three types of injuries in sagittal CT scan slice. Different treatment regimens were used to manage the posterior malleolar fractures. And visual analogue score (VAS) was introduced to assess the therapeutic outcomes., Results: The ratio between the length of posterior malleolar articular and the total length of articular surface decreased from Type A to Type C (χ(2) = 187.453, P = 0.0000). The ratio was (34 ± 15)% for Type A, (30 ± 9)% for Type B and (12 ± 10)% for Type C. A follow-up study was performed in Type A injury (n = 58), Type B injury (n = 31) and Type C injury (n = 167) at 12 months. According to VAS score, there was no significant difference between the patients undergoing fixation and not (all P > 0.05)., Conclusion: Different causes of posterior malleolar fracture results in different sizes of posterior malleolar fragment and strategies of treatment. The anatomic reduction of posterior malleolar fragment remains a key aspect of achieving satisfactory outcomes in all kinds of injury.

Objective: To assess the effect of the autologous venous external stents on intimal hyperplasia of the vein grafts in rabbits., Methods: Thirty-six male New Zealand white rabbits, aged 5 months and weighing 2.8 to 3.0 kg, were randomly divided into 3 groups: group A, group B and group C, with 12 rabbits in each group. First, a section about 6 cm long of vein was cut from the right external jugular vein of each rabbit and severed to have 3 equal-length segments. Next, each distal segment prepared for anastomosis. The proximal segment invaginating middle segment in group A and only middle segment in group B were used for the external stent. Later, the left common carotid artery was separated from surrounding tissue, from it a section about 0.5 cm long was cut away. Finally, the vein graft was inverted and end-to-end anastomosed to the two ends of the artery with a 9-0 suture. After bloodstream re-established, the diameter of each vein graft was measured. At 2 and 4 weeks postoperative, the graft veins were cut off and histologically examined by the means of HE staining and Masson staining. The smooth muscle cells (SMC) proliferation was studied by the immunohistochemical detection of proliferating cell nuclear antigen., Results: After bloodstream re-established, the diameters of vein graft of group A and group B and group C were (1.6 +/- 0.3) mm, (2.2 +/- 0.4) mm and (2.6 +/- 0.6) mm respectively (P < 0.05). At 4 weeks postoperative, the data of the ratio of intima to media thickness and the index of the proliferating cells of the intima were as follow: group A (1.01 +/- 0.07 and 6.84 +/- 1.98), group B (1.32 +/- 0.08 and 11.01 +/- 2.61), group C (1.55 +/- 0.03 and 14.96 +/- 4.14). Both the data of group A were obviously less than that in group B, and that of group B was less than group C (P < 0.05)., Conclusion: The autologous venous two-layer external stents inhibit intimal hyperplasia of the vein grafts.

Background/purpose: Although the general profile of oral biopsies from Asian children has been reported, it was still worth examining whether there were racial and geographic variations in the categories and incidence of pediatric oral lesions. This retrospective study mainly evaluated the categories and incidence of biopsied oral lesions in Taiwanese pediatric patients., Methods: Biopsy records of all oral lesions from pediatric patients, aged 0-14 years, in the files of the Department of Pathology, National Taiwan University Hospital from 1988 to 2007 were evaluated. The patients were divided into three age groups (0-5, 6-10, and 11-14 years), and the oral lesions were classified into four main categories: inflammatory and reactive, cystic, neoplastic, and other lesions., Results: Of a total of 11,986 biopsied oral lesions, 797 (6.6%) were found in pediatric patients. The most common oral lesions were inflammatory and reactive (45.5%), followed by neoplastic (23.5%), cystic (22.2%), and other (8.8%) lesions. The majority of oral biopsies (47.3%) were taken from patients in the 11-14 years age group. Of the 187 oral neoplastic lesions, 178 (95%) were benign and nine (5%) were malignant, including two premalignant lesions. The maxilla (66 cases) and the mandible (61 cases) were the two most common sites for pediatric neoplastic lesions. The top five oral lesions in pediatric patients were mucous extravasation phenomenon (195 cases), dentigerous cyst (84 cases), odontoma (83 cases), radicular cyst (38 cases), and dental follicle (26 cases)., Conclusion: The mucous extravasation phenomenon, odontoma, or dentigerous cyst was the most common inflammatory and reactive, neoplastic, or cystic lesion, respectively, in pediatric patients. The relatively high incidence of inflammatory and reactive lesions in pediatric patients implies the importance of stringent oral hygiene in children. Most oral neoplastic lesions in pediatric patients are benign, and malignant oral tumors rarely occur in pediatric patients.

Effects of macronutrient (NO3(-) -N and NH4(+) -N) on inorganic carbon system of water with Ulva pertusa existed were studied in laboratory simulation experiments. The results demonstrated that nutrient enrichment induced DIC, HCO3- and p(CO2) decreased while pH and CO3(2-) increased. The seawater changed from carbon source to carbon sink. During the experiments, the concentration of DIC, HCO3- and p(CO2) decreased with increasing concentration of nutrient when the NO3(-) -N and N4(+) -N were less than critical concentration. The concentration of DIC changed most at the NO3(-3) and NH4(-)3 groups, which decreased 151 micromol x L(-1) and 232 micromol x L(-1) compared with the control groups in the end of experiment. The increased dry weight of Ulva pertusa (deltam) of nutrient addition groups showed a significant negative correlation with deltaDIC (r = - 0.91, p < 0.0001, n = 11). The main controlling factor to inorganic carbon variation is the adaptation of Ulva pertusa to different DIN. When the concentration of DIN facilitates the growth of Ulva pertusa, the concentration of DIC decreased and dry weight of Ulva pertusa increased. NH(4) -N has more influence on inorganic carbon system than NO(3-) -N.

Objective: To assess the effect of the different treatments targeted at different types of radial head fracture and radial neck fracture., Methods: A retrospective study was performed in 87 patients from February 2006 to March 2007. Fifty-four patients with radial head fractures included 36 males and 18 females, aged from 18 to 65 years (the average age was 33); Forty of them resulted from crashing, 8 from traffic injury and 6 from falling injury. According to Mason classification system, there were 15 type I, 23 type II and 16 type III. Thirty-three patients with radial neck fractures included 21 males and 12 females, aged from 9 to 17 years (the average age was 13), 29 of them resulted from crashing, 1 from traffic injury and 3 from falling injury. According to O'Brien classification system, there were 8 type I, 14 type II and 11 type III. Type I of radial head fractures and radial neck fractures were immobilization with cast, the patients with type II of radial head fractures were treated with open reduction and micro-screw or T-trapezoid and bridge-shaped plate fixation and type III had operations to fix with bridge-shaped locked plate and repair the broken annular ligament, or replace heads with prosthesis. All patients with type II and type III of radial neck fractures were treated with closed reduction by leverage and percutaneous intra-medullary nailing., Results: The patients were followed up for 4-12 months (mean 7.2 months). The functional recovery degrees were evaluated with Wheeler's evaluation system. In group of radial head fractures, the results were excellent in 26 patients, good in 20, fair in 6 and poor in 2, the excellent and good rate was 85.2%. In group of radial neck fractures, the results were excellent in 20 patients, good in 9, fair in 4 and poor in no patient, and the excellent and good rate was 87.9%., Conclusions: Different types of fractures should choose different surgical methods according to their characters. The excellent functional recovery depend on anatomical reduction, retaining the head of radius, early repairing and protecting the broken annular ligament of radius, and early functional training.

Objective: To study the biomechanical properties of self-designed calcaneal anatomical plate and pre-cut gudgeon system and its efficacy for calcaneal fracture fixation., Methods: Sixteen fresh foot specimens were randomly divided into experimental group and the control group. Axial compressive load were applied to all specimens in order to create a calcaneal fracture model, and the maximum load and the maximum arch displacement of experimental group were recorded. In experimental group, self-designed intenal fixation system were utilized, while the AO plate internal fixation system were utilized in the control group. Axial compressive test were applied again to both groups, and the maximum load, the foot arch displacement and calcanus broadens were measured and recorded., Results: Comparison between before and after fixing the calcaneus fracture by self-designed internal fixation system in experimental group, the difference of the maximum load was significant (P<0.01), but there was no significant difference (P>0.05) of the maximum arch displacement. All parameters were significantly different (P<0.01) between the experimental group and the control group., Conclusion: The fractured calcaneus will be able to regain normal foot biomechanical function after treated by self-designed internal fixation system, and able to support foot arch to bear great load. The self-designed internal fixation and pre-cut gudgeon system is considered to outperform the conventional AO internal fixation system with its better effectiveness and outcome in treating calcaneus fractures.

This 7-year-old girl experienced pain in her upper central incisors following a fall to the ground. Radiographic examination revealed immature upper central incisors with mid-root oblique and horizontal root fractures. Splinting was performed. When at 3 months, an electric pulp test was positive for both injured teeth, and after 5 months, the fracture lines had disappeared on the radiographs, the splint removed. After 2 years, clinical examination showed normal tooth color and position, with a positive response to the pulp test. Radiographs demonstrated continuous root development, although root canal narrowing was noted at the healed fracture sites.

Incontinentia pigmenti (IP) is a rare X-linked dominant inherited disorder which has a variety of ectodermal aberrations. Skin hyperpigmentation is the most characteristic feature of IP. However, extracutaneous anomalies involving dentition, hair, eyes, and central nervous system are also found. The dental anomalies reported include peg-shaped or malformed teeth, hypodontia, delayed eruption, and impacted tooth. This report describes the dental anomalies in 2 IP patients who had the characteristic features of skin hyperpigmentation. One was a 13-year-old girl who had slender cone-shaped permanent anterior teeth, hypodontia, and delayed eruption of teeth which are characteristic dental anomalies in an IP patient. The other was a 10-year-old girl who only had 2 tulip-shaped maxillary permanent central incisors with shorter tapering roots but no congenital missing teeth or delayed eruption of teeth. Our findings suggest that IP may present a broad variation of dental anomalies individually. However, the characteristic finding of permanent anterior teeth with a longer crown and a shorter root found in both of our IP patients may be worthy of consideration in the differential diagnosis of IP.

2-Hydroxy-ethyl methacrylate (HEMA) is the major component released from resin-modified glass ionomer cements and dental adhesives. Human tissues mainly affected by HEMA are oral epithelium and dental pulp. We treated human gingival epithelial S-G cells and pulp fibroblasts (HPF) with various concentrations of HEMA, to evaluate its effects on cell growth, cell cycle progression, intracellular glutathione (GSH) level and reactive oxygen species (ROS) production. HEMA-induced growth inhibition in HPF and S-G cells in a dose-dependent manner, which may be partially explained by induction of cell cycle perturbation. G(2)/M phase arrest was noted after exposure of HPF to 5 and 10mm of HEMA, concomitant with glutathione depletion and ROS production. S-phase arrest occurred in S-G cells when treated with 2.5 and 5mm, while at 10mm a sub-G(0)/G(1) peak was noted, indicating the potential induction of apoptosis. GSH depletion was marked in S-G cells only at concentrations of 5 and 10mm, but excessive ROS production was noted at concentration of 1mm and rose with dose increase between 1 and 5mm, then lessened at 10mm. This suggested that the increase of ROS in S-G cells was not mainly caused by GSH depletion. These results helped to define the mechanism of the cytotoxicity caused by HEMA.

Objectives: The aim of this study was to develop a continuous flow system to mimic the kinetics of salivary flow in the mouth and to study the fluoride (F) release/uptake characteristics of both a conventional (Fuji IX) and a resin-modified glass ionomer (Vitremer) in such system., Methods: Five discs were made for each material. The disc was suspended in a drip chamber sustaining 2 ml of deionized water. The flow rate was controlled at 20 ml/h by an infusion pump. The F release in the drip chamber was assessed at designated time points for up to 6 days. The discs were subjected to 1 min exposures of 0.2% sodium fluoride (NaF); the F re-release was assessed for another 12 h., Results: Following a brief initial burst of F release, the rate decreased rapidly. Vitremer reached a steady low after 8 h, while Fuji IX reached a steady low after 90 min. Cumulative F release was measured from both the effluence and the drip chamber and showed that Vitremer released and took up more F than Fuji IX, both before and after F treatment. Cumulative amounts of fluoride in the drip chamber were much less than that in the effluence. The daily release rate patterns from the two materials were parallel. However, the hourly release rate of Vitremer decreased more gradually than Fuji IX. After sodium fluoride (NaF) treatment, F can be recharged easily and re-released rapidly within 90 min., Conclusion: This study indicates that the continuous flow method can be used to assess F release/uptake of the material. This method may represent a closer model to in vivo conditions.

Objectives: This study attempted to find a method of restoring the tensile bond strength of glass ionomer cement (GIC) to saliva contaminated enamel under unrinse condition., Methods: One hundred and thirty human non-carious permanent teeth were divided into two major groups. Either treatment with air drying, acetone, polyacrylic acid, maleic acid, tartaric acid, Scotchbond primer or no treatment at all was applied to both clean and saliva contaminated enamel surfaces prior to GIC placement. Samples were debonded in tension after 7 days of storage in water using a universal testing machine. Statistical analysis was performed using one-way ANOVA, Tukey's studentized range test and Wilcoxon's rank sums test to determine the significance of the difference of tensile bond strengths within and between the two major groups., Results: Bond strength of GIC to clean enamel was 2.46+/-0.79 MPa while the bond strength of GIC to wet contaminated enamel was significantly reduced to 1.28+/-0.32 MPa (p<0.01). However, the bond strengths were restored when the contaminated enamel surfaces were air-dried (2.19+/-0.38 MPa) or applied with either maleic acid (2.80+/-0.63 MPa) or Scotchbond primer (2.13+/-0.65 MPa) before placing GIC over the enamels., Conclusions: Air drying, or application of maleic acid or Scotchbond primer to the contaminated enamel without rinsing prior to GIC placement can restore the tensile bond strength to a level similar to that of non-contaminated control.

Background and Purpose: Although the effectiveness of neodymium yttrium aluminum garnet (Nd:YAG) laser and fluoride anticaries treatment has been established, most previous studies focused on smooth tooth surfaces. We evaluated the anticaries effects of Nd:YAG laser combined with fluoride varnish (Duraphat) on caries-susceptible pit and fissure areas., Methods: A total of 36 noncarious molars were treated with either a Nd:YAG laser (2.5 W, 6 sec) followed by fluoride varnish, Nd:YAG laser only, fluoride varnish only, or no treatment (control). Artificial carious lesions were created to assess the acid resistance of enamel after treatment. Undecalcified successive tooth slices were made. Percentage lesion formation, lesion length, and lesion depth were evaluated using polarized light microscopy., Results: The Nd:YAG laser enhanced the resistance of dental enamel to acid challenge. However, Nd:YAG laser alone was not as effective as the Nd:YAG laser combined with fluoride varnish, especially for the treatment of pits and fissures. Nd:YAG laser treatment combined with fluoride varnish inhibited 43% of lesions at pits and fissures and 80% of lesions on smooth surfaces compared to no treatment. Carious lesions had shallower depth and shorter length. No carious lesion extended beyond the dentinoenamel junction in either laser-treatment group., Conclusions: A synergistic effect on dental caries prevention in pit and fissure areas and on the smooth surfaces of the tooth can be achieved by applying Nd:YAG laser followed by fluoride varnish.

Plaque pH measurements can be used to detect individual's caries susceptibility and the cariogenic potential of ingested foods. However, repeated measurements with a touch electrode at a single site may affect the metabolic state of the dental plaque and result in changes of its inherent pH values. The purposes of this study were to evaluate the influence of repeated measurements of resting plaque pH values and to determine the pH values at different interdental sites. Eleven dental students participated in the study. The dental plaque was built up after thorough oral hygiene care. The subjects were then instructed to maintain a normal diet but to refrain from any oral hygiene care for the next 48 hours. Measurement of plaque pH was performed with an antimony electrode at 6 interproximal sites, including central spaces between the upper and between the lower central incisors, and the area between the second premolar and the first molar in each quadrant. At each tested site, measurements were taken 5 times at 0, 10, 30, 45 and 60 min. The results showed that the plaque pH became slightly alkaline at all the tested locations after repeated measurements. However, only the lower incisor area showed a significant change in pH values. Interdental plaque on the lower arch showed higher pH values than did that on the upper arch. There was no significant difference between the pH values on the right and left corresponding sites as determined using the Wilcoxon signed ranks test.

Fluoride(F) iontophoresis is preferred over topical application to provide long lasting dentin desensitization. The purpose of this study was to evaluate the changes in dentinal tubules following fluoride iontophoresis under SEM observation. Teeth were divided mainly into 3 groups: controls, NaF treated teeth with iontophoresis and those without inotophoresis. A battery operated device was used to apply electric current to teeth. All the teeth were prepared for scanning electron microscopy after treatments. Fluoride treatment, either non-iontophoretic or iontophoretic, produced granular precipitation in dentinal tubules and reduced tubular diameter. In 5-minute non-iontophoretic NaF treated teeth, the depth of precipitate penetration was 75 microns on average where the granules were small and sparse. In the 5-minute iontophoretic NaF treated teeth, the average penetration of precipitation reached 250 microns in one application whereas in three applications to teeth the average depth of penetration reached 830 microns. Fluoride iontophoresis resulted in obstruction of dentinal tubules. Both the frequency and duration od treatment under constant current and voltage affected the size of particles, the form of precipitation and the depth of penetration. Larger particle size and deeper fluoride penetration were observed in iontophoresis treated teeth compared to non-iontophoresis treated teeth. Therefore, repeated fluoride iontophoresis treatment is suggested to ensure long lasting densensitization effects.

In order to understand the changes in location of the mandibular foramen with age in children, lateral cephalometric radiographs from 112 child and adult patients, including both males and females, were randomly selected according to age. The subjects were divided into 6 age-groups; 3, 5, 7, 9, 11 and adult. Certain lines and points were traced on the radiographs used. The location of the mandibular foramen was identified by two persons. The perpendicular distance from the center of the mandibular foramen to the occlusal plane and the location of the mandibular foramen relative to the ramus height (Ar-Kk), as well as to the ramus width (a-p), were measured. The mandibular foramen was located 4.12 mm below the occlusal plane at the age of 3. It subsequently moved upward with age. By the age of 9, it had reached approximately the same level as the occlusal plane. The foramen continued to move upward to 4.16 mm above the occlusal plane in the adult group. The height percentage averages ranged from the lower 1/3 of the ramus height in the 3 year-old group to the middle of the ramus height in adults. The depth percentage averages ranged from 67.8% in 3 year-old children to 61.7% in adults. For greater accuracy in anesthetic procedures, dentists should relate the locational changes in the mandibular foramen with age when performing block anesthesia for the inferior alveolar nerve.

The prevalence of mottled enamel (dental fluorosis) was investigated among children, aged 6 to 15 years, in Chung-hsing New Village and in Tsao-tun Village. The drinking water in Chung-hsing New Village has been fluoridated for 12 years at a level of 0.6 ppm, while the drinking water in Tsao-tun contains a negligible level of 0.08 ppm. The degree of mottled enamel was assessed by using Dean's Index and the Community Fluorosis Index (CFI), the latter being derived from Dean's Index for the purpose of comparison. In Dean's Index, 6 classes based on the severity of the mottling, are identified: normal, questionable, very mild, mild, moderate, and severe. The results showed that children in Chung-hsing had whiter teeth than those in Tsao-tun Village. In the fluoridated group, 5.8% of children fell into the "very mild" mottling category, as compared to 0.9% in Taso-tun, the control area. For the "mild" class, the rate was 1.9% for Chung-hsing New Village and 0.4% for Tsao-tun. With only one exception in Tsao-tun, none of the children in the two groups showed mottling in the "moderate" or "severe" classes. The Community Fluorosis Index (CFI) was 0.15 for the Chung-hsing group, indicating that the occurrence of mottled enamel is very low when compared with data from fluoridation programs in other countries. It is concluded that in Taiwan, a 0.6 ppm fluoride concentration in drinking water, which has previously been reported to be effective in prevention of dental caries, is associated with only negligible mottling of enamel. Even when mottling does occur, the degree is very mild and only small chalky spots can be seen on the teeth.

Powdered human enamel treated for three minutes each with a CaHPO4 x 2H2O forming solution and a fluoride solution, and then suspended in "synthetic saliva" for 72 hours acquired a large amount of apatitic fluoride. This apatitic fluoride appears to form after the fluoride treatment.

Deposition of fluoride (F) in the skeleton is a major factor in the metabolic regulation of F. The progressive increase in bone F levels with age suggests that F is rather firmly sequestered once it is deposited in bone. We have examined the extent to which F is resorbed and redeposited during bone turnover in growing rats. The skeleton was first preloaded with F by intake of water containing a high level of F (50 mg F/L) and simultaneously labeled with [3H]tetracycline (3H-TC) to provide a measure of subsequent bone turnover. Rats were then changed to a very low F intake, and bone F loss was compared with 3H-TC loss in animals undergoing normal bone turnover or turnover accelerated by a low calcium (Ca) intake. Approximately 60% of F mobilized during bone resorption was redeposited in the skeleton (humerus and vertebrae). The redeposition of F showed a positive correlation with mineral deposition. Thus the retention of F in the skeleton of growing rats results predominantly from redeposition of resorbed F rather than passive retention associated with low bone turnover.

The purposes of this study were to compare: (i) the fluoride (F) uptake by enamel in approximal areas of teeth when the F agent was applied in vitro via a tray or a flossing technique; and (ii) the effectiveness of two treatments--acidulated phosphate fluoride (APF) alone and CaHPO4.2H2O (DCPD)-forming pre-treatment followed by APF. Groups of three teeth (one premolar and two molars) were mounted in impression compounds simulating their oral configuration. In the tray group, teeth received one four-minute treatment by means of custom-formed trays. In the flossing group, the approximal areas of teeth were flossed for 40 sec twice daily for three days with an absorbent floss wetted with the treatment solution. All teeth were incubated in a saliva-like solution except during treatment. At the end of the three-day period, teeth were unmounted and washed in 1 mol/L KOH for 24 hours. The F uptake was calculated from biopsy data obtained before and after the treatment. The results showed that (i) DCPD-APF produced significantly greater F uptake than APF alone in both the tray and flossing methods, and (ii) the flossing technique produced significantly greater F uptake in the approximal areas than the tray method for either treatment.

Along with an evaluation of the effects of 12 years' water fluoridation in the prevention of caries, the present study was conducted to explore the influence of water fluoridation on the eruption of permanent teeth. The survey was carried out in fluoridated Chung-Hsing New Village and the control town of Tsao-Tun from October to December, 1984. Dental examinations were performed on 3,459 children Chung-Hsing New Village and 4,610 in Tsao-Tun, at ages ranging from 3 to 15 years. The results showed that in general, the mean tooth eruption time of girls was earlier than that of boys, and that teeth in the lower jaw emerge sooner than their homologues in the upper jaw, except for premolars. In both fluoridated and control areas the order of tooth eruption was very similar except for the teeth of girls in the upper jaw. The eruption sequence was first premolar, canine then second premolar in the girls of Chung-Hsing New Village, while first premolar, second premolar then canine in those of Tsao-Tun. By comparing the eruption time of permanent teeth in the children of fluoridated and control areas, it was found that they were very alike in general, the only difference being observed in the premolars of the sexes. The premolars of the children in the fluoridated area emerged in the oral cavity 2.5 to 4.5 months later than did their counterparts in the control area.(ABSTRACT TRUNCATED AT 250 WORDS)

Phosphate deficiency imposed on weanling rats for two wk resulted in a 40% increase in alkaline phosphatase activity of incisor pulp, without a significant change in Ca2+-, Mg2+-ATPase activity. The results are consistent with a separate identity for the two enzymes, but their physiological roles remain obscure.

The ability of the adult skeleton to retain fluoride (F) during times of Ca stress was assessed in lactating rats. Rats incorporated F into their skeletons throughout growth by consumption of water containing 50 ppm F from weaning to 11 weeks of age. The rats were then changed to a low-F intake and mated. At delivery, nine dams were killed as a baseline group, and 20 dams were fed a low-F diet plus distilled water during lactation. Half of the rats were subjected to the additional stress of a low-Ca intake to stimulate bone resorption. F loss was determined during lactation. Bone turnover was measured by the loss of previously incorporated tritiated tetracycline (3H-TC), and changes in bone Ca and F contents were compared with changes in 3H-TC content. The extent of bone resorption ranged from 16.5% in the humerus of the adequate-Ca group to 77.1% in the vertebrae of Ca-deficient dams. Loss of bone F was greatest in animals with greatest loss of 3H-TC. Once F was resorbed from bone, only a relatively small portion was redeposited (0-31.4%). The low extent of F redeposition appears to be related to a low Ca deposition in lactating rats.