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151.
Early osteoblastic activity on TiO2 thin films decorated with flower-like hierarchical Au structures
Spyridon Kalantzis Salih Veziroglu Theresa Kohlhaas Christian Flrke Yogendra Kumar Mishra Jrg Wiltfang Yahya Ail Franz Faupel Oral Cenk Aktas Aydin Gülses 《RSC advances》2020,10(48):28935
Titanium alloys are the most commonly used dental and orthopedic implant materials due to their proven biocompatibility and mechanical properties. The native oxide layer (TiO2 layer) formed on such Ti-based implants acts as the self-protecting layer against possible ion release. Increasing the oxide layer thickness further on such TiO2 implants even opens the triggering of the osseointegration process if the oxide layer is having a certain degree of roughness, preferably higher. This work reports a novel photocatalytic patterning of sputter deposited TiO2 layers with flower-like Au structures to enhance the early osteoblastic activity. The prepared hierarchical Au structures, composed of micro- and nanoscale features on the top, lead to improved number of filopodia formation. This suggest that proposed Au–TiO2 surface may foster the cell attachment and as well as cell proliferation.Flower-like hierarchical Au structures, composed of micro- and nanoscale features, lead to higher number of filopodia formation on TiO2 thin films. 相似文献
152.
Cesur S Kocaturk PA Kavas GO Aksaray S Tezeren D Ciftci U 《The Journal of infection》2005,50(1):31-33
The aim of this study was to measure the alterations in serum trace element concentrations, including zinc (Zn) and copper (Cu) in patients with brucellosis and to compare them with the results of healthy individuals. Seventy-five subjects, 60 patients with brucellosis and 15 healthy individuals were included in this study. The serum Zn and Cu concentrations were measured by using atomic absorbtion spectrophotometer in sera of patients with brucellosis and statistically compared with those of healthy individuals. Serum Cu concentration was found to be significantly higher in patients with brucellosis than that of healthy individual (130.5+/-24.7, 96+/-8.65 microg/dl, respectively) (p < 0.01). Serum Zn concentration was lower in patients with brucellosis than those of healthy subjects (79.5 +/-13.5 and 83+/-5.59 microg/dl, respectively) (p < 0.01). Serum trace element concentrations showed significant alterations in patients with brucellosis compared with healthy subjects. 相似文献
153.
Glucose and fat metabolism in adipose tissue of acetyl-CoA carboxylase 2 knockout mice 总被引:3,自引:0,他引:3 下载免费PDF全文
Oh W Abu-Elheiga L Kordari P Gu Z Shaikenov T Chirala SS Wakil SJ 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(5):1384-1389
Acc2-/- mutant mice, when fed a high-fat/high-carbohydrate (HF/HC) diet, were protected against diet-induced obesity and diabetes. To investigate the role of acetyl-CoA carboxylase 2 (ACC2) in the regulation of energy metabolism in adipose tissues, we studied fatty acid and glucose oxidation in primary cultures of adipocytes isolated from wild-type and Acc2-/- mutant mice fed either normal chow or a HF/HC diet. When fed normal chow, oxidation of [14C]palmitate in adipocytes of Acc2-/- mutant mice was approximately 80% higher than in adipocytes of WT mice, and it remained significantly higher in the presence of insulin. Interestingly, in addition to increased fatty acid oxidation, we also observed increased glucose oxidation in adipocytes of Acc2-/- mutant mice compared with that of WT mice. When fed a HF/HC diet for 4-5 months, adipocytes of Acc2-/- mutant mice maintained a 25% higher palmitate oxidation and a 2-fold higher glucose oxidation than WT mice. The mRNA level of glucose transporter 4 (GLUT4) decreased several fold in the adipose tissue of WT mice fed a HF/HC diet; however, in the adipose tissue of Acc2-/- mutant mice, it was 7-fold higher. Moreover, lipolysis activity was higher in adipocytes of Acc2-/- mutant mice compared with that in WT mice. These findings suggest that continuous fatty acid oxidation in the adipocytes of Acc2-/- mutant mice, combined with a higher level of glucose oxidation and a higher rate of lipolysis, are major factors leading to efficient maintenance of insulin sensitivity and leaner Acc2-/- mutant mice. 相似文献
154.
Yesilova Z Pay S Oktenli C Musabak U Saglam K Sanisoglu SY Dagalp K Erbil MK Kocar IH 《Rheumatology international》2005,25(6):423-428
Considerable discrepancies exist in the literature with respect to plasma total homocysteine (tHcy) levels in Behçets disease (BD). The aim of this study was to evaluate tHcy concentrations in these patients. Thirty-two patients with BD and 20 age- and body mass index-matched healthy volunteers were enrolled. Plasma tHcy concentrations were significantly higher, while vitamin B12 and folate levels were significantly lower in patients with thrombosis and eye involvement than those without. C-reactive protein levels also correlated significantly in a negative manner with vitamin B12 and folate but positively with tHcy. In conclusion, increased use or accelerated catabolism of folate and vitamin B12 due to chronic inflammation and moderately increased tHcy concentrations related with deficiency of these cofactors, and immunosuppressive drug administration might be potential threats of vascular disease in BD. 相似文献
155.
Celik B Bilgin S Yuksel C 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2011,38(2):194-196
Mounier-Kuhn syndrome, or tracheobronchomegaly, is a rare clinical and radiologic condition characterized by marked tracheobronchial dilation and recurrent lower respiratory tract infections. Diagnosis is typically accomplished with the use of computed tomography and bronchoscopy, as well as pulmonary function testing. Patients may be asymptomatic; however, symptoms can range from minimal with preserved lung function to severe respiratory failure. Therapy, if any, is supportive but minimal. Surgery rarely has a place in the treatment of Mounier-Kuhn syndrome.Herein, we report the case of a 58-year-old man with chronic obstructive pulmonary disease who had a chronic cough, increased sputum production, and chest pain. Thoracic computed tomography showed tracheal dilation (diameter, 34 mm) and multiple diverticula in the posterior region of the trachea. Fiberoptic bronchoscopy revealed enlarged main bronchi, the dilated trachea, and prominent tracheal diverticula. Pulmonary function testing disclosed impaired respiratory function. Histopathologic examination of biopsy specimens from the bronchi and the tracheal wall supported the diagnosis of Mounier-Kuhn syndrome. The patient was released from the hospital and his condition was monitored for 2 years, during which time he developed no lower respiratory tract infections.Regardless of radiologic findings that suggest recurrent lower respiratory tract infection, we recommend that Mounier-Kuhn syndrome be considered in the differential diagnosis. 相似文献
156.
Kuyucu T Güçlü SZ Saylan B Demir C Senol T Güner S Koyuncu E Ozen F Oztürk S Cangül Z Ağanoğlu S Ozkaya S Ocak SC Akkurt H Intepe YS Bayrak MG Güler T Bekçi TT Soyyiğit S Seyfettin S Kula O Akbay MO Büyükgöze B Asal G Başlilar S Oztürk O;Turkey SUNRISE Study Group 《Tüberküloz ve toraks》2011,59(4):328-339
Chronic obstructive pulmonary disease (COPD) is a lung disease characterized with limitation of airflow that is not completely reversible, progressive deterioration of airways and systemic inflammation. This study has been planned to determine daily symptom variability of patients, expectations of patient and physicians from treatment and patient profiles. A total of 514 patients with COPD from 25 centers were included in this national, multicenter, cross-sectional observational study. Data regarding demographic features, concomitant diseases, history and treatment of COPD and expectations of patients and physicians were all obtained in a single visit. Mean [standard deviation (SD)] age of the patients was 64.1 (9.5) years; age range was 41-92 years, 50% of the patients were younger than 65 years and 91% were males. Educational level of the patients was at least primary school in 80.2%; and 54.3% (30.4%) of the patients had at least one concomitant disease, particularly a cardiovascular disease. Mean (SD) duration of having COPD was 5.4 (4.6) years. The majority of patients were at moderate (43.2%) and severe (35.0%) COPD stages and one or more exacerbations per year was determined in 71%. Inhaled beta-2 agonists (84.2%), inhaled steroids (76.3%) and inhaled long-acting anti-cholinergics (70.0%) were the most commonly used medications. Dyspnea (99.0%), sputum production (92.8%) and wheezing (90.5%) were the most common symptoms, and symptom variability for dyspnea (41.1%), sputum production (61.0%) and cough (53.5%) were seen the most in the morning hours (p< 0.001). Most commonly affected morning activity was climbing up/down the stairs (point of effect: 6.7), followed by wearing socks/shoes (point of effect: 4.3) and showering/bathing (point of effect: 4.2) by COPD. Major treatment expectations of patients were greater symptomatic relief (82.3%) and greater mobility (70.0%), faster symptomatic relief (61.1%) and improvement in morning activities (59.3%); while major treatment expectations of physicians included increased quality of life (100.0%) and decreased morbidity (96.0%). Quitting smoking was the most commonly recommended (88.3%) and implemented (67.9%) non-drug protective approach aimed at decreasing the frequency of exacerbations. Consequently, our results demonstrate that COPD is not a disease of only the elderly, is an important healthcare issue that often disrupt daily living of the patients due to inadequate disease awareness leading to overlooking of the symptoms by patient and physicians, and that a patient-centered approach based on the living standards, life expectancies and preferences of patients was crucial in patient management. 相似文献
157.
Sahinarslan A Yalcin R Kocaman SA Ercin U Tanalp AC Topal S Bukan N Boyaci B Cengel A 《The Canadian journal of cardiology》2011,27(5):589-595
Background
Erythropoietin has been shown to induce neovascularization and protect against ischemic vascular injury. We investigated whether a higher serum erythropoietin (EPO) level is related to better coronary collateral vessel grade.Methods
Ninety-nine patients with stable angina pectoris who have at least 1 coronary stenosis of equal to or greater than 70% at coronary angiography were prospectively enrolled. Serum EPO and vascular endothelial growth factor (VEGF) levels were studied. Coronary collateral degree was graded according to the Rentrop method. Patients with grade 2-3 collateral degree were included in the good collateral group and formed Group I. The patients with grade 0-1 collateral degree were included in the poor collateral group and formed Group II.Results
The serum EPO level was significantly higher in the good collateral group (17.3 ± 9.3 mU/mL vs 11.7 ± 5.0 mU/mL; P < 0.001). There was also a positive correlation between serum EPO level and Rentrop score (r = 0.39; P < 0.001). In multivariate analysis, serum EPO level (odds ratio [OR] 1.336; 95% confidence interval [CI], 1.120-1.593; P = 0.001), oxygen saturation (OR 0.638; 95% CI, 0.422-0.963; P = 0.033) and presence of chronic total occlusion (CTO) (OR 26.7; 95% CI, 3.874-184.6; P = 0.001) were independently related to well-developed coronary collaterals.Conclusions
Higher serum EPO level is related to better coronary collateral development. Erythropoietin may have a positive effect on the development of collaterals and may provide a new agent for the treatment strategies to enhance coronary collateral vessel development. 相似文献158.
Decup F Six N Palmier B Buch D Lasfargues JJ Salih E Goldberg M 《Clinical oral investigations》2000,4(2):110-119
Bone sialoprotein (BSP), an osteogenic protein (OP), mixed with a carrier, was implanted in the pulp of rat first upper molars
(OP group). Cavities were prepared with dental burs and pulp perforation was carried out by pressure with the tip of a steel
probe. After 8, 14, and 30 days, the rats were killed and the pulps of the OP group were compared with (1) a sham group (S
group), (2) a group where the carrier was implanted alone (C group), and (3) capping with calcium hydroxide (Ca group). After
8 days, a few inflammatory cells were seen, mostly located at the pulp surface near the perforation. In the Ca group, a dentin
bridge started to form, in contrast to the other groups. After 15 days, globular structures were seen in the pulps of the
S and C groups. A reparative osteodentin bridge isolated the pulp from the cavity in the Ca group. Variable reactions were
seen in the OP group, with some evidence of cell and matrix alignments or plugs of osteodentin in continuity with an inner
layer of reparative dentin. After 30 days, irregular osteodentin formation was observed in the pulps of the S and C groups,
with a tendency for globular structures to merge, but with interglobular spaces filled by pulp remnants. In the Ca group,
osteodentin was observed in the mesial part of the pulp chamber. In the BSP-implanted group, the osteogenic protein stimulated
the formation of a homogeneous dentin-like deposit occupying most of the mesial part of the pulp. Apparently, BSP stimulates
the differentiation of cells which secrete an organized extracellular matrix more efficiently than any other capping material
used so far. Altogether, the results reported here support that bone sialoprotein displays novel bioactive properties and
is capable of stimulating in 1 month’s time the development of a thick reparative dentinal tissue in the pulp, occluding the
perforation and filling the mesial third of the pulp chamber.
Received: 13 October 1999 / Accepted: 6 December 1999 相似文献
159.
160.
Gunsar F Akarca US Ersoz G Kobak AC Karasu Z Yuce G Ilter T Batur Y 《Antiviral therapy》2005,10(6):721-726
The only beneficial agent for the treatment of chronic delta hepatitis (CDH) is interferon (IFN). However, there is no consensus on the best dosage or duration of IFN therapy. As ribavirin (RBV) increases the sustained response when added to IFN in chronic hepatitis C, probably because of its immunomodulatory effect, we aimed to investigate the efficacy of 2-year IFN treatment and whether RBV had any additive effect to IFN in CDH. METHODS: Patients (n = 31) with CDH were randomized with a 1:2 ratio as 10 patients (3 females/7 males, age 39 +/- 9) receiving IFN monotherapy (9 MU IFN-alpha2a three times weekly) and 21 patients (8 females/13 males, age 38 +/- 11) receiving IFN plus RBV for 2 years (IFN at the same dosage and RBV at 1000-1200 mg/day). Alanine transferase normalization and hepatitis delta virus (HDV) RNA negativity at the end of treatment and at the end of the follow-up period (at least 6 months following 2-year treatment) were primary endpoints of the study. In addition, virological response and biochemical response were determined separately. RESULTS: Eight of 31 patients (25%) had cirrhosis in liver biopsies. Six patients from the IFN monotherapy group and 12 patients from the combination group had biochemical response. Five patients from the IFN monotherapy group and 11 patients from the combination group had virological response at the end of therapy. Two patients from the IFN group and five patients from the combination group had sustained biochemical response at the end of the follow-up period. Hepatitis B virus (HBV) activations with HBV DNA positivity were observed in two patients (one from the IFN monotherapy group, one from the combination group). Two patients (20%) in the IFN group and five patients (23.5%) in IFN plus RBV group remained as virological responders at the end of the follow-up period (P > 0.05). None of the patients with liver cirrhosis were responsive at the end of the follow-up period. CONCLUSION: Almost 20% of the patients with CDH were responsive to 2-year IFN treatment at the end of the follow-up period and no additional effect of RBV was observed. Patients with advanced liver disease failed to respond to treatment. 相似文献