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81.
Aydin S Ozercan IH Geckil H Dagli F Aydin S Kumru S Kilic N Sahin I Ozercan MR 《Journal of biochemistry and molecular biology》2007,40(3):368-372
Ghrelin belongs to the family of a gut-brain hormone that promotes food intake and controls energy balance. Recently, it has also been shown to regulate bone formation directly. Dental tissue shares several functional, developmental and anatomical similarities with bone, and in the present study we have investigated the presence of ghrelin in 44 human teeth using immunocytochemistry and radioimmunoassay. Both methods showed that the hormone is present in canines and molars, mainly in the odontoblasts but also in the pulp. Ghrelin could potentially play interesting physiological roles in teeth. 相似文献
82.
H. Turan Akkoyun Ahmet Uyar Mahire Bayramoglu Akkoyun Aydın Şükrü Bengü Şule Melek Fatma Karagözoğlu Sevinç Aydın Suat Ekin Sinem Aslan Erdem 《Journal of biochemical and molecular toxicology》2023,37(2):e23248
This study aimed to investigate the protective effects of arbutin (ARB) against brain injury induced in rats with potassium bromate (KBrO3). The rats were divided into four groups as Group 1: Control (0.9% NaCl ml/kg/day p.), Group 2: KBrO3 (100 mg/kg (gavage), Group 3: ARB (50 mg/kg/day p.), and Group 4: KBrO3 + ARB (100 mg/kg (gavage) + 50 mg/kg/day p.). At the end of the fifth day of the study, the rats in all groups were killed, and their brain tissues were collected. In the collected brain tissues, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured, and routine histopathological examinations were made. The MDA levels in the group that was exposed to KBrO3 were significantly higher than those in the control group (p ˂ 0.001). In comparison to the KBrO3 group, the MDA levels in the KBrO3 + ARB group were significantly lower (p ˂ 0.001). It was observed that SOD and CAT enzyme activity levels were significantly lower in the KBrO3 group compared to the control group (p ˂ 0.001), while these levels were significantly higher in the KBrO3 + ARB group than in the KBrO3 group (p ˂ 0.001). Additionally, the group that was subjected to KBrO3 toxicity, as well as ARB administration, had much lower levels of histopathologic signs than the group that was subjected to KBrO3 toxicity only. Consequently, it was found that KBrO3 exposure led to injury in the brain tissues of the rats, and using ARB was effective in preventing this injury. 相似文献
83.
84.
Steven T. Lott Nanyue Chen Dawn S. Chandler Qifeng Yang Luo Wang Marivonne Rodriguez Hongyan Xie Seetharaman Balasenthil Thomas A. Buchholz Aysegul A. Sahin Katrina Chaung Baili Zhang Shodimu-Emmanu Olufemi Jinyun Chen Henry Adams Vimla Band Adel K. El-Naggar Marsha L. Frazier Khandan Keyomarsi Kelly K. Hunt Subrata Sen Bruce Haffty Stephen M. Hewitt Ralf Krahe Ann McNeill Killary 《PLoS medicine》2009,6(5)
Background
Breast cancer in young women tends to have a natural history of aggressive disease for which rates of recurrence are higher than in breast cancers detected later in life. Little is known about the genetic pathways that underlie early-onset breast cancer. Here we report the discovery of DEAR1 (ductal epithelium–associated RING Chromosome 1), a novel gene encoding a member of the TRIM (tripartite motif) subfamily of RING finger proteins, and provide evidence for its role as a dominant regulator of acinar morphogenesis in the mammary gland and as an independent predictor of local recurrence-free survival in early-onset breast cancer.Methods and Findings
Suppression subtractive hybridization identified DEAR1 as a novel gene mapping to a region of high-frequency loss of heterozygosity (LOH) in a number of histologically diverse human cancers within Chromosome 1p35.1. In the breast epithelium, DEAR1 expression is limited to the ductal and glandular epithelium and is down-regulated in transition to ductal carcinoma in situ (DCIS), an early histologic stage in breast tumorigenesis. DEAR1 missense mutations and homozygous deletion (HD) were discovered in breast cancer cell lines and tumor samples. Introduction of the DEAR1 wild type and not the missense mutant alleles to complement a mutation in a breast cancer cell line, derived from a 36-year-old female with invasive breast cancer, initiated acinar morphogenesis in three-dimensional (3D) basement membrane culture and restored tissue architecture reminiscent of normal acinar structures in the mammary gland in vivo. Stable knockdown of DEAR1 in immortalized human mammary epithelial cells (HMECs) recapitulated the growth in 3D culture of breast cancer cell lines containing mutated DEAR1, in that shDEAR1 clones demonstrated disruption of tissue architecture, loss of apical basal polarity, diffuse apoptosis, and failure of lumen formation. Furthermore, immunohistochemical staining of a tissue microarray from a cohort of 123 young female breast cancer patients with a 20-year follow-up indicated that in early-onset breast cancer, DEAR1 expression serves as an independent predictor of local recurrence-free survival and correlates significantly with strong family history of breast cancer and the triple-negative phenotype (ER−, PR−, HER-2−) of breast cancers with poor prognosis.Conclusions
Our data provide compelling evidence for the genetic alteration and loss of expression of DEAR1 in breast cancer, for the functional role of DEAR1 in the dominant regulation of acinar morphogenesis in 3D culture, and for the potential utility of an immunohistochemical assay for DEAR1 expression as an independent prognostic marker for stratification of early-onset disease. 相似文献85.
Opl?nder C Volkmar CM Paunel-G?rgülü A Fritsch T van Faassen EE Mürtz M Grieb G Bozkurt A Hemmrich K Windolf J Suschek CV 《Nitric oxide》2012,26(2):132-140
Vascular ischemic diseases, hypertension, and other systemic hemodynamic and vascular disorders may be the result of impaired bioavailability of nitric oxide (NO). NO but also its active derivates like nitrite or nitroso compounds are important effector and signal molecules with vasodilating properties. Our previous findings point to a therapeutical potential of cutaneous administration of NO in the treatment of systemic hemodynamic disorders. Unfortunately, no reliable data are available on the mechanisms, kinetics and biological responses of dermal application of nitric oxide in humans in vivo. The aim of the study was to close this gap and to explore the therapeutical potential of dermal nitric oxide application. We characterized with human skin in vitro and in vivo the capacity of NO, applied in a NO-releasing acidified form of nitrite-containing liniments, to penetrate the epidermis and to influence local as well as systemic hemodynamic parameters. We found that dermal application of NO led to a very rapid and significant transepidermal translocation of NO into the underlying tissue. Depending on the size of treated skin area, this translocation manifests itself through a significant systemic increase of the NO derivates nitrite and nitroso compounds, respectively. In parallel, this translocation was accompanied by an increased systemic vasodilatation and blood flow as well as reduced blood pressure. We here give evidence that in humans dermal application of NO has a therapeutic potential for systemic hemodynamic disorders that might arise from local or systemic insufficient availability of NO or its bio-active NO derivates, respectively. 相似文献
86.
Kepenek Eda Seyma Ozcinar Evren Tuncay Erkan Akcali Kamil Can Akar Ahmet Ruchan Turan Belma 《Molecular and cellular biochemistry》2020,463(1-2):33-44
Molecular and Cellular Biochemistry - Excitation–contraction coupling in normal cardiac function is performed with well balanced and coordinated functioning but with complex dynamic... 相似文献
87.
Koyu A Gokcimen A Ozguner F Bayram DS Kocak A 《Molecular and cellular biochemistry》2006,284(1-2):81-85
Abstact Cadmium is one of the most toxic pollutants in environment. Cadmium accumulation in blood affects the renal cortex and causes
renal failure. In this study, we aimed to evaluate the effects of cadmium on rat liver tissue. Eighteen male albino rats aged
ten weeks old were used in the study. 15 ppm of cadmium was administered to rats via consumption water daily. At the end of
the 30th study day, the animals were killed under ether anesthesia. After the liver tissue samples were taken, histopathological
and biochemical examinations were performed. Histopathologic changes have included vacuolar and granular degenerations in
hepatocytes, heterochromatic nucleuses and sinusoidal and portal widenings. Central vein diameters were normal in cadmium
exposed group. Whereas, there was statistically significant difference between two groups by means of sinusoidal (p< 0.001) and portal triad diameters (p< 0.01). Malondialdehyde (MDA) is an indicator of lipid peroxidation. In this study, MDA was used as a marker of oxidative
stress-induced liver impairment in cadmium exposed rats. Superoxide dismutase (SOD) and catalase (CAT) activities were also
measured to evaluate the changes in antioxidative system in liver tissues. Current findings showed that MDA levels were increased
and SOD and CAT activities were decreased in cadmium exposed group compared to control group. The difference between two groups
was statistically significant (pvalues: MDA,p< 0.01; CAT,p< 0.01 and SOD,p< 0.05). In conclusion, these findings suggest the role of oxidative mechanisms in cadmium-induced liver tissue damage 相似文献
88.
Ahmet Gül Huri Ozdogan Burak Erer Serdal Ugurlu Ozgur Kasapcopur Nicole Davis Serhan Sevgi 《Arthritis research & therapy》2015,17(1)
IntroductionThis open-label pilot study aimed to investigate the efficacy of canakinumab in colchicine-resistant familial Mediterranean fever (FMF) patients.MethodPatients with one or more attacks in a month in the preceding 3 months despite colchicine were eligible to enter a 30-day run-in period. Patients who had an attack during the first run-in period advanced to a second 30-day period. At the first attack, patients started to receive three canakinumab 150 mg subcutaneous injections at 4-week intervals, and were then followed for an additional 2 months. Primary efficacy outcome measure was the proportion of patients with 50 % or more reduction in attack frequency. Secondary outcome measures included time to next attack following last canakinumab dose and changes in quality of life assessed by SF-36.ResultsThirteen patients were enrolled in the run-in period and 9 advanced to the treatment period. All 9 patients achieved a 50 % or more reduction in attack frequency, and only one patient had an attack during the treatment period. C-reactive protein and serum amyloid A protein levels remained low throughout the treatment period. Significant improvement was observed in both physical and mental component scores of the Short Form-36 at Day 8. Five patients had an attack during the 2-month follow-up, occurring median 71 (range, 31 to 78) days after the last dose. Adverse events were similar to those observed in the previous canakinumab trials.ConclusionCanakinumab was effective at controlling the attack recurrence in patients with FMF resistant to colchicine. Further investigations are warranted to explore canakinumab’s potential in the treatment of patients with colchicine resistant FMF.
Trial registration
ClinicalTrials.gov . Registered 16 March 2010. NCT01088880Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0765-4) contains supplementary material, which is available to authorized users. 相似文献89.
Ayca Ozkul Ahmet Sair Ali Akyol Cigdem Yenisey Turhan Dost Canten Tataroglu 《Neurochemical research》2014,39(5):853-861
Lithium (Li) and lamotrigine (LTG) have neuroprotective properties. However, the exact therapeutic mechanisms of these drugs have not been well understood. We investigated the antioxidant properties of Li (40 and 80 mg/kg/day) and LTG (20 and 40 mg/kg/day) in a rat model of global cerebral ischemia based on permanent bilateral occlusion of the common carotid arteries (BCAO). Nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione reductase (GSH-R), catalase (CAT) and superoxide dismutase (SOD) levels were measured as an indicator of oxidative–nitrosative stress in both prefrontal cortex (PFC) and hippocampus after 28 days of treatment. The spatial learning disability was also assessed at the end of the study by Morris water maze (MWM) test. All oxidative–nitrosative parameters were found to be higher in the groups under treatment than in sham. Both drugs caused a decrease in PFC NO and MDA elevation, meanwhile the increase in GSH, GSH-R, CAT and SOD levels was significantly more evident in treated groups. We also found higher PFC GSH-R and hippocampal SOD levels in BCAO + Li (80 mg/day) treated group when compared with BCAO + LTG 40 mg/day. MWM test data showed a similar increase in spatial learning ability in all groups under treatment. We found no other statistical difference in comparison of treated groups with different dosages. Our findings suggested that Li and LTG treatments may decrease spatial learning memory deficits accompanied by lower oxidative–nitrosative stress in global cerebral ischemia. Both drugs may have potential benefits for the treatment of vascular dementia in clinical practice. 相似文献
90.
There is growing awareness that endocytic trafficking plays a critical role in cell–cell communication during animal development. We are beginning to understand how endocytosis can initiate, modulate or terminate signaling. In contrast, our knowledge of the mechanisms involved in secreting signaling peptides remains more limited, particularly when it comes to secretion at the apical surface in epithelial cells. In this study, we review the mechanisms that control secretion in Caenorhabditis elegans , focusing on the role of Patched family members and the V0 complex of the vacuolar-adenosine triphosphatase (V-ATPase) in secreting Hedgehog-related peptides and of MIG-14/Wls and the retromer complex in secreting EGL-20/WNT. 相似文献