Biochemical markers in cartilage injury and repair [Kikirdak yaralanmasi ve onariminda biyokimyasal belirteçler.]

PubMed ID: 18180578Articular cartilage is a highly specialized tissue composed of chondrocytes which regulate the metabolism of extracellular matrix molecules responsible for maintaining cartilage function. Chondrocytes and synoviocytes are metabolically highly active cells and respond to various factors such as hormones, cytokines, growth factors, and mechanical stresses. Under normal physiological conditions, degradation and synthesis of extracellular matrix molecules are maintained in a state of balance. Any disruption of this balance results in degenerative cartilage diseases such as osteoarthritis and rheumatoid arthritis. Currently, diagnoses of both diseases are based on the assessment of a combination of clinical symptoms and radiological findings. However, degenerative changes in the articular cartilage occurs long before radiological changes are observed. Therefore, new laboratory tools are required to detect cartilage degradation in the early phase of the disease, to show the progression of cartilage destruction, and to assess response to treatment. In recent years, there has been an increase in the use of some biochemical markers derived from bone and cartilage for the diagnosis and follow-up of cartilage diseases. In this paper, the utility of these markers for early diagnosis and follow-up of cartilage injury is discussed in the light of the current literature

Articular cartilage homeostasis after anterior cruciate ligament reconstruction

PubMed ID: 9604193Several factors may be responsible for osteoarthritis after anterior cruciate ligament (ACL) reconstruction. The detrimental effect of the surgical technique may explain part of the progression of the pathologic process. In this study, the effect of ACL reconstruction on articular cartilage was investigated by measuring proteoglycan fragments (PF) in synovial fluid collected from patients who had undergone this operation. Synovial samples were obtained from 44 patients with chronic ACL deficiency aged 26 ± 7 years preoperatively, and from some of them, samples were collected for monitoring at 1 month (n = 22), 3 months (n = 17), 6 months (n = 18) and 12s month (n = 18). Synovial fluid taken from 12 contralateral asymptomatic knees of 12 patients (not necessarily opposite knees of ACL-deficient cases) served as controls. Preoperative values were significantly larger than controls (P < 0.05). PF level reached its maximum value in the 1st month (P < 0.05) and then gradually decreased. It was significantly lower than preoperative values at 6 and 12 months but still greater than controls (P < 0.05). It seems that surgical trauma affects cartilage metabolism for the first 3 months postoperatively. Although reconstruction of the ACL contributes to articular cartilage homeostasis, a complete return to normal values cannot be achieved in 1st postoperative year at least in knees with chronic ACL deficiency. Long-term monitoring is needed to see whether these findings are early signs of osteoarthritis. Further studies may more clearly demonstrate the effect of the surgical procedure on knees with acute and subacute ACL deficiency

Sepsis-induced changes in behavioral stereotypy in rats; Involvement of tumor necrosis factor-alpha, oxidative stress, and dopamine turnover

PubMed ID: 24007816Background Sepsis-associated encephalopathy (SAE) is defined as a diffuse or multifocal cerebral dysfunction that generally occurs early during severe sepsis. The complete pathophysiology of SAE is unknown, but several mechanisms including endotoxins, inflammatory mediators, the alteration of amino acids and of neurotransmitters, apoptosis, oxidative stress, and blood-brain barrier dysfunction have been suggested. The aim of the present study was to explore the relationship between behavioral stereotypy and plasma levels of tumor necrosis factor-alpha (TNF-?) and malondialdehyde (a marker of lipid peroxidation), and brain homovanillic acid content (a marker of dopamine turnover) in a surgically induced sepsis model in rats. Materials and methods Twenty-two adult male Sprague Dawley rats were included in the study. The cecal ligation and puncture procedure was performed to induce sepsis model. Apomorphine-induced stereotypy test was achieved 24 h after cecal ligation and puncture surgery and then, blood and brain samples were collected for biochemical measurements. Results Significantly higher stereotypy score was found in sepsis group than in the sham group (P = 0.008). Furthermore, septic rats revealed significantly higher plasma TNF-? (P = 0.002) and malondialdehyde levels (P = 0.002), and brain homovanillic acid (P = 0.004) compared with sham rats. There was a significant and positive correlation between the behavioral and biochemical parameters. Conclusions Taken together, these results demonstrate the association between inflammatory response, oxidative stress, and stereotypic behavior in an experimental sepsis model. More comprehensive experimental and clinical studies are required to clarify the specific mechanisms underlying SAE. © 2014 Elsevier Inc. All rights reserved

Effect of nitric oxide on postoperative adhesion formation.

Peritoneal adhesions continue to be a significant cause of postoperative complications. The purpose of the present study was to investigate the effect of nitric oxide in preventing postoperative adhesion formation in rats. Three randomized groups of Sprague-Dawley rats were subjected to a standardized lesion by cecal abrasion and parietal peritoneal defect. 0.9% NaCl (control, group 1), L-arginine (300 mg/kg, group 2) and Nomega-nitro arginine methyl ester (L-NAME; 25 mg/kg, group 3) were administered intraperitoneally before abdominal closure and during 3 consecutive days after surgery. Two weeks after surgery, a relaparotomy was performed and the extent of adhesion formation was determined. In groups 1 and 3 heavy adhesions were detected. In the L-arginine group, adhesion formation was significantly less than in the other groups (p < 0.05). This study showed that L-arginine reduced adhesion formation

Nicotine interacts with sex in affecting rat choice between 'look-out' and 'navigational' cognitive styles in the morris water maze place learning task

PubMed ID: 9739007The effect of sex and nicotine on cognitive style was examined in rats using a water maze task that allows differentiation between cognitive ability and style. During the 12-day acquisition period with the platform in the same location (either visible or hidden) there were no effects or interactions attributable to nicotine and sex, either in terms of learning rate or asymptotic latency. On the final test day the platform was visible and shifted in its location, and on the first trial the new location was proximal to the rats starting position, in contrast to the more distal location of the platform during the previous acquisition days. This platform relocation presented the rats with a choice between two competing cognitive styles: using local visual (look-out) cues vs. navigational cues. Performance on the test day yielded a nicotine x sex interaction, such that only saline-treated female rats showed a clear preference for the perceptual-proximal look-out cognitive style by swimming straight to the newly-relocated visible platform with mean escape latency that approximated the limits of swimming speed. The other three groups did not differ from each other, and preferred navigational cues. The results show that male and female rats use different strategies in problem solving, and that nicotine shifts the female pattern to that of the male.Lütfiye Kanıt was awarded the “Young Investigator Award: 1st prize” in the 1997 National Congress of Physiological Sciences, Adana, Turkey, with her contribution in this study. Supported by Grant SBAG 15/3 from the Scientific and Technical Research Council of Turkey (TUBITAK). -

Accumulation of ? -Synuclein in Cerebellar Purkinje Cells of Diabetic Rats and Its Potential Relationship with Inflammation and Oxidative Stress Markers

Objective. The present study was conducted to evaluate the relationship between plasma oxidative stress markers such as malondialdehyde (MDA) and glutathione (GSH), inflammatory marker pentraxin-3 (PTX3), and cerebellar accumulation of ?-synuclein in streptozotocin- (STZ-) induced diabetes model in rats. Methods. Twelve rats were included in the study. Diabetes (n=6) was induced with a single intraperitoneal injection of streptozotocin (STZ, 60 mg/kg). Diabetes was verified after 48 h by measuring blood glucose levels. Six rats served as controls. Following 8 weeks, rats were sacrificed for biochemical and immunohistochemical evaluation. Results. Plasma MDA levels were significantly higher in diabetic rats when compared with the control rats (p<0.01), while plasma GSH levels were lower in the diabetic group than in the control group (p<0.01). Also, plasma pentraxin-3 levels were statistically higher in diabetic rats than in the control rats (p<0.01). The analysis of cerebellar ?-synuclein immunohistochemistry showed a significant increase in ?-synuclein immunoexpression in the diabetic group compared to the control group (p<0.01). Conclusion. Due to increased inflammation and oxidative stress in the chronic period of hyperglycemia linked to diabetes, there may be ?-synuclein accumulation in the cerebellum and the plasma PTX3 levels may be assessed as an important biomarker of this situation. © 2017 Volkan Solmaz et al

Investigation of Turkish nurses frequency and knowledge of administration of intramuscular injections to the ventrogluteal site: Results from questionnaires

Background Intramuscular injection is important in the administration of parenteral medication and is a frequently-performed nursing responsibility. Objective The objective of this study was to identify the frequency of use of the ventrogluteal site and the level of nurses' knowledge of administering an intramuscular injection to this site. Design A descriptive cross-sectional study was conducted of nurses working in four hospitals (n = 362). Data collection tools included a 12 item sociodemographic questionnaire and a 24 item questionnaire on knowledge of the ventrogluteal site for intramuscular injection. Findings 17.1% of participants reported using the VG site frequently in intramuscular injections. On the other hand, 35.9% reported that they do not use the VG site in intramuscular injections just because they are not used to giving injections on this site. Level of knowledge of ventrogluteal site was also limited with the mean score of correct answers from 24 questions being 14.37. Conclusion It was found in the study that nurses' knowledge of the ventrogluteal site was limited, and they are not preferentially using the ventrogluteal site for intramuscular injections to adults even though it is recommended in recent nursing literature. © 2017 Elsevier Lt

Exenatide reduces TNF-? expression and improves hippocampal neuron numbers and memory in streptozotocin treated rats

PubMed ID: 26386291Recent studies suggest a possible link between type 2 diabetes and Alzheimer's disease (AD). Glucogan-like peptide 1 (GLP-1) facilitates insulin release from pancreas under hyperglycemic conditions. In addition to its metabolic effects, GLP-1 and its long-lasting analogs, including exenatide can stimulate neurogenesis and improve cognition in rodent AD model. The aim of the present study was to investigate the effects of exenatide on hippocampal cellularity, cognitive performance and inflammation response in a rat model of AD. Fourteen rats were used to create AD model using intracerebroventricular (ICV) streptozotocin (STZ) infusion while 7 rats were administered 0.9% NaCl only (sham-operated group). Following stereotaxic surgery, STZ received rats were randomly distributed into two groups, and treated with either saline or exenatide 20 µgr/kg/day through intraperitoneally for two weeks. Then, cognitive performance (passive avoidance learning), brain tumor necrosis factor alpha (TNF-?) levels, choline acetyltransferase (ChAT) activity and hippocampal neuronal count were determined. While the brain TNF-? levels were significantly high in the saline-treated STZ group, exenatide treatment suppressed the increase in TNF-? levels. Saline-treated STZ group showed reduced ChAT activity compared to sham group. However, exenatide significantly preserved brain ChAT activity. The cognitive performance was also impaired in saline group while exenatide improved memory in rats. Moreover, exenatide treatment significantly prevented the decrease in hippocampal neurons. Overall, the results of the present study clearly indicated exenatide might have beneficial effects on impaired cognitive performance and hippocampal neuronal viability in AD by suppressing the inflammation response and increasing cholinergic activity. © 2015 Published by Elsevier B.V