1,721,024 research outputs found
Determination of Storage Time of Saliva Samples Obtained From Patients With and Without Chronic Periodontitis for the Comparison of Some Biochemical and Cytological Parameters
No full textBackground: Salivary glutathione (GSH), malondialdehyde (MDA), protein, sialic acid (SA) levels, cytological parameters, and tissue factor activities (TFa) were investigated when fresh and after 3, 7, 11, 15, 21, and 30 days (d) of storage at -20 degrees C both in the control and the periodontitis group. Moreover, the control and the periodontits groups were compared and continuity of the significances detected between the two groups were evaluated. Methods: GSH, MDA, SA, protein, and TFa were determined using the methods of Beutler, Yagi, Warren, Lowry, and Quick, respectively. Saliva imprint samples were stained with Giemsa and microscopically examined. Results: When the continuity of the significances of differences between the two groups was investigated, differences continued to be significant for GSH and TFa on days 3, 7, 11, 15, 21, and 30. Cytologically, only the significance detected between leucocyte numbers continued to be significant for 30d. However significance of differences in total protein, MDA, and SA levels on day 0, were interrupted on days 3, 7, and 11, respectively. Conclusion: Saliva samples may be stored for 30d for GSH and TFa analyses in patients with and without periodontitis. However, to compare salivary MDA, SA, and total protein levels in these groups we suggest fresh samples to be studied. (C) 2013 Wiley Periodicals, Inc
Milrinone Attenuates Heart and Lung Remote Injury after Abdominal Aortic Cross-Clamping
No full textBackground: Phosphodiesterase enzymes play a pivotal role in the pathogenesis of ischemia/reperfusion (IR). We examined the role of milrinone (MIL), a phosphodiesterase 3 inhibitor, on remote injury of the heart and lung after abdominal aortic cross-clamping. Design: Experimental study. Methods: Twenty-one Wistar rats were divided into 3 groups: (1) control (C, n = 7), underwent laparotomy and exploration of abdominal aorta only; (2) IR (n = 7), normal saline was applied intraperitoneally (i.p) before IR induced by clamping of the abdominal aorta for 1 hr and then allowing reperfusion for 1 hr; and (3) MIL + IR (n = 7), MIL was given (0.5 mg/kg, i.p) before IR. After sacrification, the lungs and hearts were taken out for analyses and the tissue malondialdehyde (MDA) and glutathione (GSH) were studied. All tissues were examined under light microscopy and transmission electron microscopy (TEM). Expressions of caveolin (Cav)-1 in the lung and Cav-1 and Cav-3 in the heart were examined immunohistochemically. Results: The MIL + IR group had significantly a lower magnitude of oxidative stress than the IR group both in the lung and heart (lung: P = 0.03 for MDA and 0.001 for GSH and heart: P = 0.002 for MDA and 0.000 for GSH). In light microscopy, the MIL + IR group had statistically a lower total injury score than the IR group for both the lung and heart tissue (P = 0.03 and P = 0.04, respectively). In TEM, regression of mitochondrial degeneration and lamellar bodies in type II pneumocytes in the lungs and obvious improvements in disruption at the intercalated discs and mitochondrial degeneration in the hearts in the MIL + IR group were detected compared with the IR group. The expression of both Cav-1 and Cav-3 in the MIL + IR group was improved compared with the IR group (P = 0.03 for both). Conclusions: MIL attenuates remote injury of heart and lung in lower body IR by inhibiting oxidative stress. Moreover, Cav-1 and Cav-3 might have a potential role in MIL-induced cardioprotection
Riboflavin Treatment Reduces Apoptosis and Oxidative DNA Damage in a Rat Spinal Cord Injury Model
No full textObjective: Spinal cord injury (SCI) leads to an inflammatory response and results in oxidative stress, which has deleterious effects on several organ systems. Riboflavin is an easily absorbed micronutrient that plays an important role in maintaining health in humans and animals. The present study was designed to investigate the putative protective effect of riboflavin against SCI-induced spinal cord and kidney damage. Methods: In order to induce SCI, the standard weight-drop method was used to induce a moderately severe injury (100 g/cm force) at the T10 vertebral level. Injured animals were given either 25 mg/kg riboflavin or carboxymethyl cellulose 15 min after injury, and this regimen was repeated twice daily for 7 days. On the 7th post-injury day, a neurological examination was performed and rats were sacrificed. Spinal cord and kidney samples were harvested and prepared for a histological examination. Tissue levels of malondialdehyde (MDA), glutathione (GSH), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) and activities of myeloperoxidase (MPO), superoxide dismutase (SOD), and caspase-3 were determined. Results: SCI caused a significant decrease in tissue GSH levels and SOD activities, which were accompanied by significant increases in MDA and 8-OHdG levels and MPO and caspase-3 activities. However, riboflavin treatment reversed these parameters and improved histological findings. Conclusion: SCI caused tissue injury through oxidative stress and neutrophil infiltration into tissues. Riboflavin inhibited tissue injury through its neuroprotective and antiapoptotic effects. Moreover, our study demonstrated that riboflavin not only exerts antioxidant and antiapoptotic effects on the spinal cord but also has a significant impact on preventing kidney damage secondary to SCI
Neuroprotective effects of mitoquinone and oleandrin on Parkinson's disease model in zebrafish
No full textAim: The aim of this study is to investigate the possible protective effects of mitoquinone and oleandrin on rotenone induced Parkinson's disease in zebrafish. Materials and methods: Adult zebrafish were exposed to rotenone and mitoquinone for 30 days. Biochemical parameters were determined by spectrophotometric method and Parkinson's disease-related gene expressions were determined by reverse transcription polymerase chain reaction method. Measurement of neurotransmitters was performed by liquid chromatography tandem-mass spectrometry instrument. The accumulation of synuclein was demonstrated by immunohistochemical staining. In vitro thiazolyl blue tetrazolium bromide method was applied to determine the mitochondrial function of synaptosomal brain fractions using rotenone as a neurotoxic agent and mitoquinone and oleandrin as neuroprotective agents. Results: Mitoquinone improved the oxidant-antioxidant balance and neurotransmitter levels that were disrupted by rotenone. Mitoquinone also ameliorated the expressions of Parkinson's disease-related gene expressions that were disrupted by rotenone. According to thiazolyl blue tetrazolium bromide assay results, mitoquinone and oleandrin increased mitochondrial function which was decreased due to rotenone exposure. Conclusion: Based on the results of our study, positive effects of mitoquinone were observed in Parkinson's disease model induced by rotenone in zebrafish
Histopathologic evaluation of saphenous vein grafts in patients with type II diabetes mellitus undergoing coronary artery bypass grafting
No full textIntroduction: Diabetes Mellitus (DM) has been known to be a risk factor for the development of more severe form of saphenous vein graft disease after coronary artery bypass grafting (CABG). We aimed to evaluate the impact of type II-DM on histopathological features of great saphenous vein grafts of patients undergoing CABG. Patients and methods: Forty consecutive patients undergoing elective CABG were enrolled into the study. Patients were grouped into two; Diabetic group (n = 20); includes patients with preoperative diagnosis of type II-DM and Nondiabetic group (n = 20): those without type II-DM. In all patients, a short segment of the great saphenous vein graft at the level of medial malleolus was taken for light microscopy and transmission electron microscopy (TEM) evaluation. Moreover, immunoexpressions of Caveolin-1, Vascular cell adhesion protein 1 (VCAM-1) and endothelial nitric oxide synthase (eNOS) were studied. Results: There were no differences in the demographics of patients between two groups. The magnitude of intimal fibrosis in diabetic group was slightly higher than in nondiabetics (1.95 +/- 0.99 versus 1.3 +/- 0.8, P = .04). In TEM, vacuolization in endothelial cells, substance accumulation along with coarse collagen fibers and cytoplasmic degeneration with vacuolization in muscle cells were detected in diabetic group. While there were no differences in Caveolin-1 and VCAM-1 immunostaining, the intensity of positive eNOS immunostaining was significantly higher in endothelium (2.10 +/- 0.64 versus 1.55 +/- 0.68, P = .01) and tunica media 1.75 +/- 0.63 versus 1.2 +/- 0.52, P = .007) in nondiabetic group, respectively) compared with diabetic group. Conclusion: Type II DM might be a reason for decreased expression of eNOS and increased intimal fibrosis, vacuolization of endothelial and smooth muscle cells in saphenous vein grafts. The clinical implications of these alterations on the graft patency need to be evaluated. (c) 2021 Elsevier Inc. All rights reserved
Tooth replantation with adipose tissue stem cells and fibrin sealant: microscopic analysis of rat's teeth
No full textTreatment for dental avulsion cases is early or late replantation of the traumatized teeth. Prognosis of the replanted tooth depends on the level of periodontal injury. Adipose tissue stem cells (ATSCs) were reported to improve periodontal ligament tissue (PDL) regeneration. Fibrin sealant (FS) contains thrombin and fibrinogen to form an adhesive fibrin clot routinely used in surgical procedures. Here, we aimed to investigate the effects of ATSCs + FS treatment on healing of PDL after tooth replantation in a rat model. After 60 min of extraction, maxillary central incisor teeth were replanted with ATSCs + FS. Two months later, the rats were sacrificed and hemimaxilla blocks were dissected out for histological analysis. The results showed that there was a significant improvement in histological findings of ATSCs + FS treated group compared to only FS treated and non-treated groups corresponding to reduced inflammatory resorption and increased new PDL formation. Furthermore, the ankylosis levels were lowered after ATSCs + FS treatment. Singular use of FS improved PDL healing moderately. Our results indicated that ATSCs + FS treatment improves PDL healing after tooth replantation suggesting a new therapeutic potential in the treatment of dental avulsion cases
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
