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121.
A human hepatoma cell line, Hep G2 cell, is reliable for the study of alcohol-induced hepatotoxicity. In this study, we investigated the effect of an aqueous extract of Artemisia capillaris Thunb (Compositae) plant (AC) on ethanol (EtOH)-induced cytotoxicity in Hep G2 cells. AC (0.5-5 microg/mL) inhibited the secretion of EtOH-induced interluekin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha). AC also inhibited the EtOH-, IL-1alpha-, and TNF-alpha-induced cytotoxicity. Furthermore, we found that AC inhibited the EtOH-induced apoptosis of Hep G2 cells. These results suggest that AC may prevent the EtOH-induced cytotoxicity through inhibition of the apoptosis of Hep G2 cells.  相似文献   
122.
The nucleocapsid (N) protein of rinderpest virus (RPV) is one of the most abundant and immunogenic viral proteins expressed during natural or experimental infection. To identify immunogenic epitopes on the N protein, different forms of RPV N protein, including the full-length protein (N(1-525)), an amino-terminal construct (N(1-179)), and a carboxy-terminal construct (N(414-496)), were expressed in Escherichia coli as glutathione S-transferase (GST) fusion proteins. The antigenicity of each recombinant protein was evaluated by Western immunoblotting. All recombinants were recognized by hyperimmune RPV bovine antisera, indicating that immunoreactive epitopes may be present at both ends of the N protein. However, GST-N(414-496) was much more antigenic than GST-N(1-179) when tested with sera from vaccinated cattle, suggesting that an immunodominant or highly immunogenic epitope(s) may be located at the carboxy terminus of the N protein. Epitope mapping with overlapping peptides representing different regions of the carboxy terminus (amino acids 415 to 524) revealed three nonoverlapping antigenic sites in regions containing the residues (440)VPQVRKETRASSR(452) (site 1), (479)PEADTDPL(486) (site 2), and (520)DKDLL(524) (site 3). Among these, antigenic site 2 showed the strongest reactivity with hyperimmune anti-RPV bovine sera in a peptide enzyme-linked immunosorbent assay but did not react with hyperimmune caprine sera raised against peste-des-petits-ruminants virus, which is antigenically closely related to RPV. Identification of an immunodominant linear antigenic site at the carboxy terminus of the N protein may provide an antigen basis for designing diagnostics specific for RPV.  相似文献   
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124.
Growth and development is the net result of environmental modulation of genetic inheritance. Mesenchymal cells differentiate into chondrogenic, osteogenic, and fibrogenic cells: the first 2 are chiefly responsible for endochondral ossification, and the last 2 for sutural growth. Cells are influenced by genes and environmental cues to migrate, proliferate, differentiate, and synthesize extracellular matrix in specific directions and magnitudes, ultimately resulting in macroscopic shapes such as the nose and the chin. Mechanical forces, the most studied environmental cues, readily modulate bone and cartilage growth. Recent experimental evidence demonstrates that cyclic forces evoke greater anabolic responses of not only craniofacial sutures, but also cranial base cartilage. Mechanical forces are transmitted as tissue-borne and cell-borne mechanical strain that in turn regulates gene expression, cell proliferation, differentiation, maturation, and matrix synthesis, the totality of which is growth and development. Thus, hereditary and mechanical modulations of growth and development share a common pathway via genes. Combined approaches using genetics, bioengineering, and quantitative biology are expected to bring new insight into growth and development, and might lead to innovative therapies for craniofacial skeletal dysplasia including malocclusion, dentofacial deformities, and craniofacial anomalies such as cleft palate and craniosynostosis, as well as disorders associated with the temporomandibular joint.  相似文献   
125.
A technique for the restoration of carious primary maxillary incisors using indirect resin composite crowns and intracanal reinforcement fiber is described. Endodontic treatment was previously performed on each tooth. The advantages of using an intracanal reinforcement fiber include resin composite crown reinforcement, translucency, and relative manipulation facility. In addition, the use of indirect resin composite crowns provides good shape and esthetics, as well as reduced chair time for the child. The technique is illustrated in a case report in which indirect resin composite crowns and an intracanal reinforcement fiber are placed in a 3-year-old girl.  相似文献   
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127.
OBJECTIVE: To test the antiadherent and antibacterial properties of surface modification of orthodontic wires with photocatalytic titanium oxide (TiO(2)). MATERIALS AND METHODS: TiO(2) was coated on the surface of the orthodontic wires by a sol-gel thin film dip-coating method. Bacterial adhesion to the wires was evaluated by the weight change of the wires. The antibacterial activity of the surface-modified orthodontic wires was demonstrated by the dilution agar plate method for Streptococcus mutans and spectrophotometry for Porphyromonas gingivalis. RESULTS: The orthodontic wires coated with the photocatalytic TiO(2) showed an antiadherent effect against S. mutans compared with the uncoated wires. The bacterial mass that bound to the TiO(2)-coated orthodontic wires remained unchanged, whereas that of the uncoated wires increased by 4.97%. Furthermore, the TiO(2)-coated orthodontic wires had a bactericidal effect on S. mutans and P. gingivalis, which cause dental caries and periodontitis, respectively. The antiadherent and antibacterial mechanisms of TiO(2) to break down the cell wall of those bacteria were revealed by scanning electron microscopy. CONCLUSION: The surface modification of orthodontic wires with photocatalytic TiO(2) can be used to prevent the development of dental plaque during orthodontic treatment.  相似文献   
128.
Vulvar carcinoma in young patients and its relationship with genital warts.   总被引:1,自引:0,他引:1  
We report the occurrence of aggressive vulvar carcinoma associated with condyloma acuminata in three patients under 33 years old. Discussion of the role of the human papilloma virus (HPV) in the development of vulvar cancer is also presented. Three patients with condyloma associated with aggressive vulvar squamous cell carcinoma, in situ (1 case) and invasive (2 cases), documented by biopsy and/or vulvectomy are presented. In situ hybridization (ISH) was used to characterize the subtypes of HPV. One patient with erythematous systemic lupus developed in situ carcinoma after 5 years. The other two cases also developed aggressive multicentric, invasive squamous cell carcinoma after 10 years of diagnosis of condyloma. In all cases HPV cytological abnormalities were seen throughout the pathological examination. HPV 16 and 18 were present in cells of invasive squamous cell carcinoma in cases 2 and 3. HPV 6 and 11 were detected only in the condyloma area in case 2. HPV 30 was seen only in the condyloma area in case 3. This report emphasizes the need for biopsies of all unusually persistent or treatment-resistant condylomas, particularly in young and/or immunosuppressed patients.  相似文献   
129.
Background/AimsThe endoscopic step-up approach is accepted as the preferred treatment for complicated or symptomatic walled-off necrosis (WON). Direct endoscopic necrosectomy (DEN) is an effective therapeutic option, but few reports describe long-term follow-up in this patient population. Thus, we aim to assess the long-term outcomes of DEN following severe necrotizing pancreatitis.MethodsThe data of all acute pancreatitis patients who underwent DEN following endoscopic transmural drainage from six referral centers between 2007 and 2017 were retrospectively collected.ResultsSixty patients (76.7% male, mean age 48.3 years) underwent a median of 4 sessions of DEN starting at a median of 45.5 days after the onset of acute pancreatitis. Clinical success was achieved in 51 patients (85%), with a 35% complication rate and a 5% mortality rate. Using multivariate analysis, the risk factor associated with DEN failure or major DEN complications requiring intervention or surgery was an identified bacterial/fungal WON infection (odds ratio, 19.3; 95% confidence interval, 1.5 to 261.7). During the median follow-up period of 27 months, complicated WON recurrence was observed in 5.3% of patients, and long-term complications occurred in 24.6% of patients (four exocrine insufficiency, nine newly developed diabetes mellitus, one recurrent small bowel obstruction, one chylous ascites).ConclusionsConsidering that long-term complications are similar to those observed after pancreatectomy, DEN should be performed meticulously while minimizing damage to the viable pancreatic parenchyma with adequate antibiotic escalation.  相似文献   
130.
Objectives.In this study, we review our institutional experience with pediatric laryngomalacia (LM) and report our experiences of patients undergoing supraglottoplasty using the spontaneous respiration using intravenous anesthesia and high-flow nasal oxygen (STRIVE Hi) technique.Methods.The medical records of 29 children with LM who visited Seoul National University Hospital between January 2017 and March 2019 were retrospectively reviewed. Surgical management was performed using the STRIVE Hi technique. Intraoperative findings and postoperative surgical outcomes, including complications and changes in symptoms and weight, were analyzed.Results.Of the total study population of 29 subjects, 20 (68.9%) were female. The patients were divided according to the Onley classification as follows: type I (n=13, 44.8%), II (n=10, 34.5%), and III (n=6, 20.7%). Twenty-five patients (86.2%) had comorbidities. Seventeen patients (58.6%) underwent microlaryngobronchoscopy under STRIVE Hi anesthesia. Four patients with several desaturation events required rescue oxygenation by intermittent intubation and mask bagging during the STRIVE Hi technique. However, the procedure was completed in all patients without any severe adverse effects. Overall, 15 children (51.7%) underwent supraglottoplasty, of whom 14 (93.3%) showed symptom improvement, and their postoperative weight percentile significantly increased (P=0.026). One patient required tracheostomy immediately after supraglottoplasty due to associated neurological disease.Conclusion.The STRIVE Hi technique is feasible for supraglottoplasty in LM patients, while type III LM patients with micrognathia or glossoptosis may have a higher risk of requiring rescue oxygenation during the STRIVE Hi technique.  相似文献   
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