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991.
Auvinen S Suominen T Hannonen P Bachinski LL Krahe R Udd B 《Arthritis and rheumatism》2008,58(11):3627-3631
Because of its high prevalence, fibromyalgia (FM) is a major general health issue. Myotonic dystrophy type 2 (DM2) is a recently described autosomal-dominant multisystem disorder. Besides variable proximal muscle weakness, myotonia, and precocious cataracts, muscle pain and stiffness are prominent presenting features of DM2. After noting that several of our mutation-positive DM2 patients had a previous diagnosis of FM, suggesting that DM2 may be misdiagnosed as FM, we invited 90 randomly selected patients diagnosed as having FM to undergo genetic testing for DM2. Of the 63 patients who agreed to participate, 2 (3.2%) tested positive for the DM2 mutation. Their cases are described herein. DM2 was not found in any of 200 asymptomatic controls. We therefore suggest that the presence of DM2 should be investigated in a large sample of subjects diagnosed as having FM, and clinicians should be aware of overlap in the clinical presentation of these 2 distinct disorders. 相似文献
992.
993.
Jingwei He Sufyan Garoushi Eija Säilynoja Pekka K. Vallittu Lippo Lassila 《Dental materials》2019,35(4):627-635
Objective
A new photocurable monomer, “Phene” (N-methyl-bis(ethyl-carbamate-isoproply-α-methylstyryl)amine) was synthesized and incorporated into Bis-GMA/TEGDMA with the aim of reducing polymerization shrinkage swithout detriment to the physical properties and wearing of the resin composites.Methods
Phene was synthesized through a 2-step reaction route, and its structure was confirmed by FT-IR and 1H-NMR spectra. Phene was incorporated into Bis-GMA/TEGDMA (50/50, wt/wt) with a series of mass fraction (from 0?wt% to 40?wt%). Experimental resin composites were prepared by mixing 29?wt% of resin matrix to 71?wt% of particulate-fillers. Degree of conversion (DC) was determined by FT-IR analysis. The volumetric shrinkage (VS) was calculated as a buoyancy change in distilled water by means of the Archimedes principle. Polymerization shrinkage-stress (SS) was measured using the tensilometer technique. The flexural strength (FS), modulus (FM), and fracture toughness (FT) were measured using a three-point bending setup. A wear test was conducted with 15000 cycles using a dual-axis chewing simulator. Wear depth was measured by a three-dimensional (3D) non-contact optical-profilometer.Results
ANOVA analysis showed that when mass fraction of Phene in resin matrix was more than 10?wt%, the obtained resin composite formulation had lower DC, VS and SS than control resin composite (p?<?0.05). In general, the experimental resin composites had comparable FS and FM (p?>?0.05) when the mass fraction of Phene in resin matrix was not more than 20?wt?%. Resin composite with 20?wt% Phene had the lowest wear depth and fracture toughness values.Significance
The overall tested properties prove that including Phene up to 20?wt% into Bis-GMA/TEGDMA resin could be potentially useful in the formulation of low-shrinkage resin composites. 相似文献994.
PURPOSE: To compare in vitro the bond strength of a particulate filler composite and two brands of fiber-reinforced composite (FRC) to teeth with or without the addition of flowable composite at the adhesive interphase. Physicomechanical properties that might contribute to the bonding were also evaluated. MATERIALS AND METHODS: Two hundred extracted human molars were used as substrates with a standard acid-etch and adhesive technique. FRC material [everStick (EV) or Stick (SC)] was applied on the substrate either directly or with a thin layer of flowable composite resin [Tetric Flow (TF)] and light cured for 40 s. As a control, particulate filler composite was used. The specimens (n = 10) were water stored for 24 h or thermocycled for 6000 cycles and subjected to shear bond strength testing. Fracture surfaces were analyzed with SEM and the microhardness and thermal expansion behavior of the materials at the adhesive interface were also evaluated. Multifactorial ANOVA and Tukey's post hoc tests were used at a significance level of p < 0.05. RESULTS: ANOVA showed that storage condition and substrate type (p < 0.05) had a significant effect on the bond strength values. Bond strengths of FRC did not show a significant difference compared to the control (p > 0.05). For enamel, the mean bond strengths in MPa (SD) after thermocycling were: control 19.4 (3.8); EV 22.3 (3.6); SC 16.9 (4.9); EV-TF 22.8 (3.2); SC-TF 16.7 (2.7); and for dentin they were: control 15.3 (5.57); EV10.2 (2.2); SC 14.4 (4.5); EV-TF 8.85 (1.1); SC-TF 15.6 (3.6). Thermocycling increased the bond strength values typically by 10%. The presence of flow composite resin did not produce any significant effect (p > 0.05). CONCLUSION: The bond strength of FRC did not differ from that of particulate filler composite, and the addition of flowable composite did not improve bond strength values. 相似文献
995.
Matilainen L Larsen KL Wimmer R Keski-Rahkonen P Auriola S Järvinen T Jarho P 《Journal of pharmaceutical sciences》2008,97(7):2720-2729
The purpose of the study was to evaluate the effect of cyclodextrin (CD) complexation on the chemical and physical stability of a polypeptide hormone glucagon and to study the interactions between glucagon and gamma-cyclodextrin molecules in inclusion complexes. The chemical stability of glucagon at pH 2.0 was studied with HPLC-UV and HPLC-MS/MS. The physical stability of glucagon at pH 2.5 was studied by measuring the turbidity (A(405 nm)) and viscosity (Ostwald capillary viscosimeter) of the samples. The structure of glucagon/gamma-CD complexes at pH 2.5 was studied with 2D-NMR. The presence of various CDs increased the chemical half-life of glucagon at pH 2.0 (37 degrees C, 0.01 M HCl, ionic strength 0.15) and prolonged the lag-time before aggregation at pH 2.5 (0.9% (w/v) NaCl in 3.2 mM HCl). The NMR studies showed that the side chains of all the aromatic amino acid residues (Phe6, Tyr10, Tyr13, Phe22, Trp25) and leucines (Leu14 and Leu26) of glucagon interacted with the cavities of the gamma-CD molecules. The present study shows that glucagon forms inclusion complexes with cyclodextrins in acidic solution, resulting in an improvement in its chemical and physical stability. 相似文献
996.
Annola K Karttunen V Keski-Rahkonen P Myllynen P Segerbäck D Heinonen S Vähäkangas K 《Toxicology letters》2008,182(1-3):50-56
Most drugs can penetrate the placenta but there are only a few studies on placental transfer of environmental toxic compounds. In this study, we used dual recirculating human placental perfusion to determine the transfer rate through the placenta of a neurotoxic and carcinogenic compound found in food, acrylamide and its genotoxic metabolite glycidamide. Putative acrylamide metabolism into glycidamide during the 4-h perfusions and acrylamide-derived DNA adducts in placental DNA after perfusions were also analyzed. Placentas were collected immediately after delivery and kept physiologically functional as confirmed by antipyrine kinetics, glucose consumption and leak from fetal to maternal circulation. Acrylamide (5 or 10 microg/ml) or glycidamide (5 microg/ml), both with antipyrine (100 microg/ml), was added to maternal circulation. Acrylamide and glycidamide were analyzed in the perfusion medium by liquid chromatography/mass spectrometry. Acrylamide and glycidamide crossed the placenta from maternal to fetal circulation with similar kinetics to antipyrine, suggesting fetal exposure if the mother is exposed. The concentrations in maternal and fetal circulations equilibrated within 2h for both studied compounds and with both concentrations. Acrylamide metabolism into glycidamide was not detected during the 4-h perfusions. Moreover, DNA adducts were undetectable in the placentas after perfusions. However, fetuses may be exposed to glycidamide after maternal metabolism. Although not found in placental tissue after 4h of perfusion, it is possible that glycidamide adducts are formed in fetal DNA. 相似文献
997.
BACKGROUND: An increased level of serum C-reactive protein (CRP) is a known prognostic factor for acute coronary events and sudden cardiac death, and it is associated with coronary calcification. CRP is expressed in coronary arteries, but its role in the development of coronary plaques is unclear. AIM: To investigate CRP immunoreactivity in relation to the severity of coronary artery disease and plaque morphology in human left anterior descending coronary arteries (LAD). METHODS: A prospective, consecutive autopsy series of 66 patients (mean age 63.4 years) in Tampere University Hospital, Tampere, Finland. RESULTS: CRP immunoreactivity was seen in 59% of the cases. In logistic regression analysis with age, sex and body mass index as confounders, CRP immunoreactivity in LAD was associated with >50% stenosis and plaque calcification. All three cases with acute coronary thrombosis due to rupture or erosion of the plaque showed a clear immunopositive reaction. CRP-positive cells were never detected in normal arteries, but were often found in early fibrous plaques (75%) and almost invariably present in the shoulder area of plaques with necrotic core (96%). CRP immunoreactivity adjacent to calcified areas in more stable plaques (71%) was less consistent with one-third of these plaques showing no immunoreactivity. CONCLUSIONS: CRP immunoreactivity is associated with the progression of atherosclerosis, and especially with unstable coronary plaques. The immunoreactivity could cease at the stable calcified stages of atherosclerosis. 相似文献
998.
999.
Hu G Jousilahti P Nissinen A Bidel S Antikainen R Tuomilehto J 《The American journal of clinical nutrition》2007,86(2):457-464
BACKGROUND: Only 2 prospective studies have previously investigated the association between coffee consumption and incident hypertension, and the findings are equivocal. OBJECTIVE: The objective was to determine the relation between coffee consumption and the incidence of antihypertensive drug treatment. DESIGN: We prospectively followed 24 710 Finnish subjects aged 25-64 y without a history of antihypertensive drug treatment, coronary heart disease, or stroke at baseline. Daily coffee consumption was assessed by questionnaires. RESULTS: During a mean follow-up period of 13.2 y, 2505 participants started antihypertensive drug treatment. The multivariate-adjusted (age, sex, study year, education, leisure-time physical activity, smoking, body mass index, high total cholesterol, history of diabetes, and alcohol, tea, fruit, vegetable, sausage, and bread consumption) hazard ratios for antihypertensive drug treatment associated with the amount of coffee consumed daily (0-1, 2-3, 4-5, 6-7, or >or=8 cups) were 1.00, 1.29 (95% CI: 1.09, 1.54), 1.26 (95% CI: 1.06, 1.49), 1.24 (95% CI: 1.04, 1.48), and 1.14 (95% CI: 0.94, 1.37) (P for trend = 0.024), respectively. This trend became marginally significant after additional adjustment for baseline systolic blood pressure (P for trend = 0.077). CONCLUSIONS: The results indicate that coffee drinking seems to increase the risk of antihypertensive drug treatment, and this risk was higher in subjects with low-to-moderate coffee intakes; however, there was no significantly increased trend in drinkers of approximately 1 cup (100 mL)/d or >or=8 cups/d. 相似文献