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OBJECTIVE@#To investigate the effects of different manners of heat exposure on thoracic aorta injury in spontaneously hypertensive rats (SHRs) and explore the underlying mechanism.@*METHODS@#Normal 6 to 7-week-old male SHRs were randomized into control group (cage at room temperature), intermittent heat exposure group (SHR-8 group, exposed to 32 ℃ for 8 h daily for 7 days) and SHR-24 group (with continuous exposure to 32 ℃ for 7 days). After the treatments, the pathologies of the thoracic aorta of the rats were observed with HE staining, and the expressions of Beclin1, LC3B and p62 were detected with Western blotting and immunofluorescence assay; TUNEL staining was used to observe cell apoptosis in the thoracic aorta, and the expressions of caspase-3, Bax, and Bcl-2 were detected using Western blotting. The effects of intraperitoneal injections of 3-MA (an autophagy agonist), rapamycin (an autophagy inhibitor) or compound C 30 min before intermittent heat exposure on the expressions of proteins associated with autophagy, apoptosis and the AMPK/mTOR/ULK1 pathway in the aorta were examined with immunohistochemistry.@*RESULTS@#In SHR-8 group, the rats showed incomplete aortic intima with disordered cell distribution and significantly increased expressions of Beclin1, LC3II/LC3I and Bax, lowered expressions of p62 and Bcl-2, and increased apoptotic cells in the thoracic aorta (P < 0.05). Pretreatment with 3-MA obviously inhibited the expressions of autophagy- and apoptosis-related proteins, whereas rapamycin promoted their expressions. Compared with the control group, the rats in SHR-8 group had significantly down-regulated p-mTOR and up-regulated p-AMPK and p-ULK1 expression of in the aorta; Treatment with compound C obviously lowered the expressions of p-AMPK and p-ULK1 and those of LC3B and Beclin1 as well.@*CONCLUSION@#In SHRs, intermittent heat exposure causes significant pathologies and promotes autophagy and apoptosis in the thoracic aorta possibly by activating the AMPK/mTOR/ULK1 pathway.
Subject(s)
Rats , Male , Animals , Rats, Inbred SHR , AMP-Activated Protein Kinases/metabolism , bcl-2-Associated X Protein/metabolism , Aorta, Thoracic , Beclin-1 , Hot Temperature , TOR Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Apoptosis , Aortic Diseases , Autophagy , Autophagy-Related Protein-1 Homolog/metabolismABSTRACT
Objective To investigate the polarization of human acute monocytic leukemia THP-1 cells-derived macrophages induced by Nippostrongylus brasiliensis proteins in vitro, so as to provide insights into the elucidation of the mechanisms underlying host immune responses to hookworm infections. Methods The in-vitro culture of N. brasiliensis was established and maintained in the laboratory, and the third- (L3) and fifth-stage larvae (L5) were collected under a sterile condition for preparation of L3 and L5 proteins. The in-vitro culture of THP-1 cells was established, stimulated with 500 ng/mL PMA to yield M0 macrophages that were adherent to the plate wall. The LPS + IFN-γ group, IL-4 + IL-13 group, L3 protein group and L5 protein group were given stimulation with 500 ng/mL LPS plus 100 ng/mL IFN-γ, IL-4 and IL-13 (both 100 ng/mL), L3 protein (5 mg/mL) and L5 protein (5 mg/mL), respectively, while the negative control group was given no stimulation. The cell morphology was observed using microscopy, the mRNA expression of M1/M2 macrophages-specific genes was quantified using a quantitative real-time PCR (qPCR) assay, and the surface markers of M1/M2 macrophages were detected using flow cytometry, while the levels of cytokines secreted by M1/M2 macrophages were measured using enzyme-linked immunosorbent assay (ELISA) following stimulations, so as to examine the polarization of THP-1-derived macrophages induced by N. brasiliensis proteins in vitro. Results Following stimulation with PMA, THP-1 cells appeared wall-adherent M0 macrophages, and polarized to typical M1 macrophages following stimulation with LPS + IFN-γ, and typical M2 macrophages following stimulation with IL-4 + IL-13, IL-3 protein or L5 protein. There was a significant difference in the proportion of M1 macrophages among the negative control group, the LPS + IFN-γ group, the IL-4 + IL-13 group, the L3 protein group and the L5 protein group (χ2 = 3 721.00, P < 0.001), with the highest proportion detected in the LPS + IFN-γ group, and there was also a significant difference in the proportion of M2 macrophages among groups (χ2 = 105.43, P < 0.001). There were significant differences among groups in terms of the mRNA expression of CCL2 (F = 191.95, P < 0.001), TNF-α (F = 129.95, P < 0.001), IL-12b (F = 82.89, P < 0.001), PPARγ (F = 11.30, P < 0.001), IL-10 (F = 9.51, P < 0.001) and Mrc1 genes (F = 12.35, P < 0.001). In addition, there were significant differences in the proportion of positive CD86 and CD206 expression among groups (χ2 = 24 004.33 and 832.50, P < 0.001). Higher IL-1β and TNF-α levels were measured in the LPS + IFN-γ group than in the IL-4 + IL-13 group, the L3 protein group and the L5 protein group (P < 0.001), and greater TGF-β1 and IL-10 levels were seen in the IL-4 + IL-13 group, the L3 protein group and the L5 protein group than in the negative control group and the LPS + IFN-γ group (P < 0.05). Conclusions Both L3 and L5 proteins of N. brasiliensis may induce the polarization of THP-1-derived macrophages to M2 type in vitro.
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Objective To establish a novel nucleic acid assay for detection of Giardia lamblia based on the recombinase-aided isothermal amplification (RAA) assay, and evaluate its sensitivity and specificity for detection of G. lamblia. Methods The specific primer sequences and florescent probes were designed and synthesized based on the G. lamblia β-giardin gene as the target gene, and a fluorescent RAA assay was established. The recombinant plasmids at various copies (containing the β-giardin gene target sequence) and the genomic DNA of G. lamblia at various concentrations were used as templates for the fluorescent RAA assay to assess the sensitivity, and the genomic DNA from G. lamblia, Schistosoma japonicum, Clonorchis sinensis, Cryptosporidium parvum, Ascaris lumbricoides, Salmonella and Shigella was used as templates to assess the specificity of the fluorescent RAA assay. Results A novel fluorescent RAA assay was successfully established for detection of G. lamblia, which allowed the rapid and specific amplification of the target gene fragments at 39 ℃ within 20 min. The sensitivities of the fluorescent RAA assay were 102 copies/μL and 1 pg/μL for detection of the recombinant plasmid and G. lamblia genomic DNA, respectively, and the fluorescent RAA assay was negative for detection of the genomic DNA from S. japonicum, C. sinensis, C. parvum, A. lumbricoides, Salmonella and Shigella, which showed a high specificity. Conclusions A fluorescent RAA assay, which is simple, sensitive and specific, is successfully established for nucleic acid detection of G. lamblia.
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Objective To investigate the risk of Anisakis infections among high-risk populations along the coastal areas of Jiangsu Province, so as to develop the strategy for the prevention and control of anisakiasis in the province. Methods Three counties along the coastal areas of Jiangsu Province were selected as the study sites in 2018, including Rudong County in Nantong City, Haizhou District in Lianyungang City and Dongtai City in Yancheng City. The knowledge, attitude and practice (KAP) of anisakiasis prevention and control, and the prevalence of serum specific IgG antibody against Anisakis were investigated among high-risk populations among these three study sites, including fishermen, fish seller and people who liked eating fresh and live marine fish. Factors affecting the prevalence of the specific IgG antibody against Anisakis were identified using a multiple logistic regression model. In addition, Anisakis larvae infections were detected in fresh and live marine fish samples collected from local markets, and the prevalence and intensity of Anisakis infections were estimated. Results A total of 625 high-risk populations were investigated, including 349 men (55.8%). Only 13.0% of the subjects heard about anisakiasis, and a low awareness rate of anisakiasis prevention and control knowledge was seen among these three types of high-risk populations. There were 21.6% of the subjects eating raw or half-cooked marine fish, 5.8% eating undercooked marine fish, 3.2% presenting vomiting, nausea and diarrhea after eating marine fish, 5.1% developing systemic allergic symptoms, and 65.6% using the same chopping board for raw and cooked food. The sero-prevalence of the anti-Anisakis IgG antibody was 7.0% among the study subjects. Multiple logistic regression analysis identified education level [OR = 0.687, 95% CI (0.478, 0.987)] and development of systemic allergic symptoms [OR = 4.641, 95% CI(1.411, 15.268)]as factors affecting the positive anti-Anisakis IgG antibody among the study subjects. Among 494 fresh and live marine fish detected, the prevalence and intensity of Anisakis larvae infection was 64.0% and 8.1 larvae per fish, with high prevalence seen in Trichiurus haumela and Pneumatophorus japonicas. Conclusions The awareness of anisakiasis prevention and control knowledge is low among the high-risk populations living along the coastal areas of Jiangsu Province, and there are high-risk behaviors, such as eating raw or half-cooked food, using the same chopping board for raw and cooked food. In addition, the prevalence of Anisakis infections is high in the marine fish in these areas. Therefore, the health education and health promotion for anisakiasis prevention and control should be intensified.
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Hookworm infection remains a global health concern, which threatens human health. Hookworm infection is widely prevalent across the world, notably in tropical and subtropical areas. Recently, with the in-depth study of the immunity of parasitic infections, the“bidirectional effect”of host immune responses induced by helminth infections (including hookworm infections) has become increasingly prominent. On one hand, an immune response is induced in the host to kill the infected worms; on the other hand, the host produces a series of immunological changes that are conducive to the maintenance of parasite survival. The immune state of the host is regulated by various complicated mechanisms, and this may lead to the reduction in the incidence of allergic and autoimmune diseases or alleviation of the disease symptoms, which provide new insights into the management of these allergic and autoimmune diseases. The present article reviewed the advances of host immune responses induced by hook-worm infection and its potential values in the treatment of allergic asthma, inflammatory bowel disease and rheumatoid arthritis.
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Objective To establish a recombinase aided isothermal amplification (RAA) assay for detection of Clonorchis sinensis. Methods The 18S ribosomal RNA (18S rRNA) sequence of C. sinensis was used as the target sequence, and specific primers and probes were designed, synthesized and screened to establish a rapid fluorescent RAA assay for the detection of C. sinensis. Then, the sensitivity of the fluorescent RAA assay was evaluated using the recombinant plasmids containing various copy numbers of DNA fragments and C. sinensis genomic DNA at various concentrations, and the specificity of the fluorescent RAA as say was evaluated using the genomic DNA of Ascaris lumbricoides, Echinococcus granulosus, Schistosoma japonicum, Ancylostoma duodenale and S. mansoni as templates. DNA samples were extracted from the feces containing C. sinensis eggs and freshwater fish containing metacercaria for the fluorescent RAA assay, and the performance for detection of C. sinensis-infected samples was preliminarily assessed in the field. Results A fluorescent RAA assay for detection of C. sinensis was successfully established, which was feasible for specific amplification of C. sinensis genomic DNA at 39 °C within 20 min. The lowest detection limit was 10 copies/μL if the recombinant plasmid containing various copy numbers of DNA fragments was used as a template, and the lowest detection limit was 3 pg/μL if the C. sinensis genomic DNA at various concentrations served as a template. All detections were negative if the genomic DNA of A. lumbricoides, E. granulosus, S. japonicum, A. duodenale, and S. mansoni was used as templates. In addition, the fluorescent RAA assay showed a high performance for the detection of C. sinensis-infected samples in the field, which successfully detected C. sinensis-infected human and rat fecal samples and Pseudorasbora parva samples. Conclusion A fluorescent RAA assay is successfully established, which is simple, rapid, sensitivity and specific for detection of C. sinensis.
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Objective To establish a recombinase-aided isothermal amplification (RAA) assay for detection of Cryptosporidium. Methods Based on Cryptosporidium-specific 18S rRNA selected as the target gene to be detected, and the primer sequences and fluorescent probes designed using the software Amplfix, and a fluorescent RAA assay was established and optimized. The fluorescent RAA assay was performed to detect 18S RNA target sequence-contained recombinant plasmids at various copies, genomic DNA of Cryptosporidium oocysts at various concentrations, and genomic DNA extracted from various numbers of Cryptosporidium oocysts to assess the sensitivity of the assay, and to detect genomic DNA extracted from Cryptosporidium oocysts, Giardia lamblia cysts, Schistosoma japonicum eggs, Ascaris lumbricoides eggs, Clonorchis sinensis eggs, Salmonella and Shigella to determine the specificity of the assay. Results A fluorescent RAA assay was successfully established, which was effective to amplify the specific 18S RNA gene fragments of Cryptosporidium within 20 min at 39 ℃. The lowest limits of the fluorescent RAA assay were 102 copies/μL for detection of 18S RNA target sequence-contained recombinant plasmids at various copies, 1 pg/μL for detection of genomic DNA of Cryptosporidium oocysts at various concentrations, and one Cryptosporidium oocyst/μL for detection of genomic DNA extracted from various numbers of Cryptosporidium oocysts, and the fluorescent RAA assay was all negative for detection of genomic DNA from G. lamblia cysts, S. japonicum eggs, A. lumbricoides eggs, C. sinensis eggs, Salmonella and Shigella. Conclusion A novel fluorescent RAA assay is successfully established, which is simple, rapid, sensitive and specific to detect genomic DNA of Cryptosporidium oocysts.
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Hookworm infection remains a global health concern, which threatens human health. Hookworm infection is widely prevalent across the world, notably in tropical and subtropical areas. Recently, with the in-depth study of the immunity of parasitic infections, the“bidirectional effect”of host immune responses induced by helminth infections (including hookworm infections) has become increasingly prominent. On one hand, an immune response is induced in the host to kill the infected worms; on the other hand, the host produces a series of immunological changes that are conducive to the maintenance of parasite survival. The immune state of the host is regulated by various complicated mechanisms, and this may lead to the reduction in the incidence of allergic and autoimmune diseases or alleviation of the disease symptoms, which provide new insights into the management of these allergic and autoimmune diseases. The present article reviewed the advances of host immune responses induced by hook-worm infection and its potential values in the treatment of allergic asthma, inflammatory bowel disease and rheumatoid arthritis.
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Objective To establish a recombinase aided isothermal amplification (RAA) assay for detection of Clonorchis sinensis. Methods The 18S ribosomal RNA (18S rRNA) sequence of C. sinensis was used as the target sequence, and specific primers and probes were designed, synthesized and screened to establish a rapid fluorescent RAA assay for the detection of C. sinensis. Then, the sensitivity of the fluorescent RAA assay was evaluated using the recombinant plasmids containing various copy numbers of DNA fragments and C. sinensis genomic DNA at various concentrations, and the specificity of the fluorescent RAA as say was evaluated using the genomic DNA of Ascaris lumbricoides, Echinococcus granulosus, Schistosoma japonicum, Ancylostoma duodenale and S. mansoni as templates. DNA samples were extracted from the feces containing C. sinensis eggs and freshwater fish containing metacercaria for the fluorescent RAA assay, and the performance for detection of C. sinensis-infected samples was preliminarily assessed in the field. Results A fluorescent RAA assay for detection of C. sinensis was successfully established, which was feasible for specific amplification of C. sinensis genomic DNA at 39 °C within 20 min. The lowest detection limit was 10 copies/μL if the recombinant plasmid containing various copy numbers of DNA fragments was used as a template, and the lowest detection limit was 3 pg/μL if the C. sinensis genomic DNA at various concentrations served as a template. All detections were negative if the genomic DNA of A. lumbricoides, E. granulosus, S. japonicum, A. duodenale, and S. mansoni was used as templates. In addition, the fluorescent RAA assay showed a high performance for the detection of C. sinensis-infected samples in the field, which successfully detected C. sinensis-infected human and rat fecal samples and Pseudorasbora parva samples. Conclusion A fluorescent RAA assay is successfully established, which is simple, rapid, sensitivity and specific for detection of C. sinensis.
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Objective To establish a recombinase-aided isothermal amplification (RAA) assay for detection of Cryptosporidium. Methods Based on Cryptosporidium-specific 18S rRNA selected as the target gene to be detected, and the primer sequences and fluorescent probes designed using the software Amplfix, and a fluorescent RAA assay was established and optimized. The fluorescent RAA assay was performed to detect 18S RNA target sequence-contained recombinant plasmids at various copies, genomic DNA of Cryptosporidium oocysts at various concentrations, and genomic DNA extracted from various numbers of Cryptosporidium oocysts to assess the sensitivity of the assay, and to detect genomic DNA extracted from Cryptosporidium oocysts, Giardia lamblia cysts, Schistosoma japonicum eggs, Ascaris lumbricoides eggs, Clonorchis sinensis eggs, Salmonella and Shigella to determine the specificity of the assay. Results A fluorescent RAA assay was successfully established, which was effective to amplify the specific 18S RNA gene fragments of Cryptosporidium within 20 min at 39 ℃. The lowest limits of the fluorescent RAA assay were 102 copies/μL for detection of 18S RNA target sequence-contained recombinant plasmids at various copies, 1 pg/μL for detection of genomic DNA of Cryptosporidium oocysts at various concentrations, and one Cryptosporidium oocyst/μL for detection of genomic DNA extracted from various numbers of Cryptosporidium oocysts, and the fluorescent RAA assay was all negative for detection of genomic DNA from G. lamblia cysts, S. japonicum eggs, A. lumbricoides eggs, C. sinensis eggs, Salmonella and Shigella. Conclusion A novel fluorescent RAA assay is successfully established, which is simple, rapid, sensitive and specific to detect genomic DNA of Cryptosporidium oocysts.
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@# Objective To analyze the epidemiological characteristics of mumps in Jiamusi city, and predict the incidence trend, so as to provide evidence for taking targeted prevention and control measures in the cold areas in Heilongjiang Province. Methods The mumps cases were collected from China Information System for Disease Control and Prevention in Jiamusi city from 2004 to 2017.Descriptive epidemiologic method was used for analyzing the epidemic of mumps in Jiamusi city during 2004-2017, and the autoregressive integrated moving average (ARIMA) was used to forecast the incidence of mumps in 2018. Results A total of 1 586 cases of mumps were reported in Jiamusi city during 2004-2017, the average annual incidence rate was 4.52/100 000. The incidence of mumps increased year by year from 2015 to 2017.The ratio of male to female was 1.67 :1,those aged from 3 to 19 years accounted for 86.32% of the total cases, the higher incidence rates were found at the age of 5-9 and 10-14 years.The incidence of mumps presented obviously seasonal characteristics.Most cases concentrated from April to July and from November to January. The incidence of urban disease was higher than that of other counties; The established finally mode was ARIMA(4,1,2)(2,0,0)12 and the predicted incidence from January 2018 to June 2018 was consistent with the actual one.From July 2018 to December 2018,predictive mumps incidence were:0.30/100 000, 0.35/100 000, 0.38/100 000, 0.39/100 000, 0.35/100 000, 0.33/100 000. Conclusions ARIMA model could predict the trend of mumps in Jiamusi city.To reduce the incidence of children, it is recommended to develop a second dose of mumps vaccine at the preschool age(3-6 years)or primary school;At the same time, surveillance and control should be continually strengthened in kindergartens and schools.
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Objective: This study was conducted to determine the proper percentage of EN in the total energy and nutrition support for critically ill patients with traumatic brain injury (TBIs). Methods: 94 cases were randomly divided into 3 groups according to the percentage of EN in the total energy: 100％ EN group in which patients received 100％ calories from EN; 75％ EN group in which patients received 75％ calories from EN, 25％ from PN; 50％ EN group in which patients received 50％ calories fromm EN, 50％ from PN. At baseline and follow-up on day 4, 7, 10, nutrition parameters, complete blood count and electrolytes as well as metabolic parameters including tests of liver and renal function were measured. Complications during treatment were recorded and the prognosis was finally judged. Results: Total protein and albumin were significantly higher in the 50％ EN and 75％ EN group on day 7 than in TEN group (P＜ 0. 05). There was significance difference found in complications between 75％EN and 50％EN group. A reduction in the length of stay in the hospital and expenses in the ICU for 10 days in the 75％ EN group (P ＜ 0. 05) was also observed. Conclusion: 75％ calories from EN in the total energy and nutrition support appeared to have great impact on management of critically ill patients with traumatic brain injury.
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<p><b>BACKGROUND</b>One-lung ventilation (OLV) is a common ventilation technology during thoracic surgery that can cause serious clinical problems. We aimed to conduct a meta-analysis to compare oxygenation and intrapulmonary shunt during OLV in adults undergoing thoracic surgery with dexmedetomidine (Dex) versus placebo to assess the influence and safety of using Dex.</p><p><b>METHODS</b>Randomized controlled trials comparing lung protection in patients who underwent thoracic surgery with Dex or a placebo were retrieved from PubMed, EMBASE, MEDLINE, Cochrane Library, and China CNKI database. The following information was extracted from the paper: arterial oxygen partial pressure (PaO2), PaO2/inspired oxygen concentration (PaO2/FiO2, oxygenation index [OI]), intrapulmonary shunt (calculated as Qs/Qt), mean arterial pressure (MAP), heart rate (HR), tumor necrosis factor-α (TNF-α), interleukin (IL)-6, superoxide dismutase (SOD), and malondialdehyde (MDA).</p><p><b>RESULTS</b>Fourteen randomized controlled trials were included containing a total of 625 patients. Compared with placebo group, Dex significantly increased PaO2/FiO2(standard mean difference [SMD] = 0.98, 95% confidence interval [CI] [0.72, 1.23], P < 0.00001). Besides, Qs/Qt (SMD= -1.22, 95% CI [-2.20, -0.23], P = 0.020), HR (SMD= -0.69, 95% CI [-1.20, 0.17], P = 0.009), MAP (SMD= -0.44, 95% CI [-0.84, 0.04], P = 0.030), the concentrations of TNF-α (SMD = -1.55, 95% CI [-2.16, -0.95], P <0.001), and IL-6 (SMD = -1.53, 95% CI [-2.37, -0.70], P = 0.0003) were decreased in the treated group, when compared to placebo group. No significant difference was found in MDA (SMD = -1.14, 95% CI [-3.48, 1.20], P = 0.340) and SOD (SMD = 0.41, 95% CI [-0.29, 1.10], P = 0.250) between the Dex group and the placebo group. Funnel plots did not detect any significant publication bias.</p><p><b>CONCLUSIONS</b>Dex may improve OI and reduce intrapulmonary shunt during OLV in adults undergoing thoracic surgery. However, this conclusion might be weakened by the limited number of pooled studies and patients.</p>
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Background Central corneal thickness (CCT)is an important parameter to evaluate corneal healthy status and is crucial for surgical planning.However,clinical study found that the center of cornea does not correspond to the thinnest point of cornea.Thus,it is essential to characterize the minimum corneal thickness(MCT) and its location.Objective Present study was to determine the thickness and location of MCT and its relationship to the fellow eye using Pentacam High Resolution technique.Methods The 564 eyes from 282 Chinese myopic patients were reviewed in this study.The CCT,MCT,pupillary central corneal thickness(PCT) and x-y coordinate of thinnest point were bilaterally measured.Written informed consent was obtained prior to the ocular biomedical measurement.Results CCT was (540.07±31.78) μm in the right eyes and (539.24±31.06) μm in the lefi eyes; PCT was (540.25±30.75)μm in the right eyes and (539.48±31.00)μm in the left eyes.MCT was (537.87± 31.91)μm in the right eyes and (536.35±31.24)μm in the left eyes,showing significant differences in all the parameters between the right eyes and left eyes expect for PCT(CCT:P=0.046;PCT:P=0.065 ;MCT:P=0.000).The C CT,PCT and M CT were significantly correlated between the right eyes and left eyes (r =0.97,0.97,0.98,P＜ 0.01).Bland-Altman plot showed a good consistence between the both eyes.The mean distance from the center was (0.50±0.21) mm in the right eyes and (0.56±0.22)mm in the left eyes,showing a significant difference (P =0.000).The difference between CCT and MCT was approximately (2.20±1.74)μm in the right eyes and (2.88±1.75) μm in the left eyes.The location of MCT in both the right eyes and left eyes tended to symmetry along the vertical midline.The distance between the R (x,y) to transformed L (x,y) was (0.29 ± 0.17)mm and the angular distance was (28.28±28.21)degree.Conclusions This study offers a range of MCT and its location in Chinese myopic patients.The difference exists between the CCT and MCT in bilateral eyes.The location of the thinnest point tends to be symmetrical along the vertical midline between the both eyes.The changes of these parameters may be helpful for the diagnosis of some corneal diseases.
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<p><b>OBJECTIVE</b>To explore the effect of combination of pulsed CO2 laser irradiation and diammine silver fluoride treatment on the ultrastructure of dentine.</p><p><b>METHODS</b>Each extracted molars was made into four identical dentinal specimens, which were randomly divided into 4 groups according to the treatment methods: A, control group; B, pulsed CO2 laser irradiation; C, coated with 38%Ag(NH3)2F; and D, laser irradiation plus fluoride. Scanning electron microscope (SEM) analysis was performed.</p><p><b>RESULTS</b>As shown by SEM, group A showed clear dentinal tubuli, group B showed melted surface without dentinal tubule openings, group C showed thicker melted layer without dentinal tubule openings, and group D showed the thickest melted and recrystallized layer on dentine surface.</p><p><b>CONCLUSIONS</b>Both pulsed CO2 laser irradiation and 38%Ag(NH3)2F treatment can seal dentinal tubule. The combination of these two techniques can form a synergistic effect.</p>
Subject(s)
Humans , Dentin , Radiation Effects , Fluorides , Pharmacology , Lasers , Lasers, Gas , Silver Compounds , PharmacologyABSTRACT
<p><b>OBJECTIVE</b>To compare the influences of gold alloy metal crown and Ni-Cr alloy metal crown on gingival health.</p><p><b>METHODS</b>Totally 20 patients requiring one metal crown restoration were divided into the gold alloy metal crown group (n=9) and Ni-Cr alloy metal crown group (n=11). The contra-lateral homonymy natural healthy teeth served as controls. Before the tooth preparation and 6 months after crown placement, the weight of gingival crevicular fluid (GCF) of each tooth (included the test teeth and the control teeth) was measured, and the probing depth and the sulcus bleeding index of each tooth were also recorded.</p><p><b>RESULTS</b>In the gold alloy metal crown group, the weight of GCF detected before the tooth preparation was significantly larger than that detected 6 months after restoration (P<0.05). In the Ni-Cr alloy metal crown group, the sulcus bleeding index recorded 6 months after restoration was significantly larger than that recorded before the tooth preparation (P<0.05). The other experimental indicators were not significantly different before and after restoration.</p><p><b>CONCLUSION</b>The gold alloy metal crowns will not cause obvious harm to the periodontal tissues of the abutments shortly after restoration, while the Ni-Cr alloy metal crowns may increase the risk of sulcus bleeding.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Chromium Alloys , Crowns , Gold Alloys , PeriodontiumABSTRACT
<p><b>OBJECTIVE</b>To study the effect of repeated firings on color of porcelain-fused-to-titanium restorations.</p><p><b>METHODS</b>Twenty standard porcelain-fused-to-titanium specimens were made with Dentsply DETREY TiBond C3 and Dentaurum rematitan Til. Then they were fired 1, 2, 4, 7, and 10 times. Color measurement was done after each firing.</p><p><b>RESULT</b>Most of the color parameters had no significant difference after firing except for a* and Hab. All the color difference among groups were smaller than 1.0 (deltaE < 1.0).</p><p><b>CONCLUSION</b>Repeated firings will not affect the color stability of porcelain-fused-to-titanium restorations.</p>