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Junko?Nio-KobayashiEmail author Kaya?Miyazaki Kazuhisa?Hashiba Kiyoshi?Okuda Toshihiko?Iwanaga 《Journal of ovarian research》2016,9(1):67
Background
The mechanisms regulating the function and regression of the corpus luteum (CL) have not yet been elucidated in detail. The regressed CL of cows was previously reported to be filled with unusual vessels like arteriovenous anastomosis (AVA); however how these vessels are being established during luteolysis remains unknown.Methods
The bovine CL at different luteal stages and regressing bovine CL induced by prostaglandin F2α (PGF) were histologically analyzed using light and electron microscopic levels. The changes in mRNA expression of genes encoding α-smooth muscle actin (SMA; Acta2) and transforming growth factor β1 (Tgfb1) in luteal tissues were analyzed by quantitative RT-PCR.Results
AVA-like vessels appeared in the regressed CL with a diameter less than 1.5 cm in which no functional luteal cells and macrophages were observed. Epithelioid cells in the AVA-like vessel wall were immunoreactive for SMA, and the lumen of the vessels were narrow. Immunoreaction for SMA was found in the tunica media of typical arteries and arterioles, and pericytes around capillary vessel. Cells with elongated cytoplasmic processes ―resident fibroblasts expressing vimentin― distributed in the CL parenchyma without any association with blood vessels are also immunoreactive for SMA, and accumulated around arteries and arterioles during the late-luteal stage. In the regressed CL, walls of arteries and arterioles consisted of more than two layers of epithelioid cells positive for both SMA and desmin, suggesting that they are myofibroblasts transformed from fibroblasts. The percentage of the area positive for SMA and the mRNA expression of Acta2 were significantly increased in the regressed CL; however, they did not alter when a luteolytic dose of PGF was injected in vivo and collected within 24 h after the injection. On the other hand, Tgfb1, a known regulator for myofibroblast transformation, was significantly increased in PGF-induced regressing CL as well as in the CL during the late-luteal stage.Conclusions
SMA-positive myofibroblasts accumulates around the arteries and arterioles to form AVA-like vessels during luteolysis in cows. PGF indirectly regulates myofibroblast transformation through enhancing the expression of TGFβ1. These peculiar AVA-like vessels may be involved in the regulation of blood flow in the bovine CL during luteolysis.95.
Kapucuoglu N Aktepe F Kaya H Bircan S Karahan N Ciriş M 《Pathology, research and practice》2007,203(3):153-162
PTEN is a tumor suppressor gene that is frequently mutated in type I endometrioid endometrial carcinomas (EECs), and is involved in the control of cell proliferation, differentiation, and apoptosis. In this study, we aimed to assess the relationship between PTEN expression and estrogen, progesterone receptors (PRs), other apoptosis-related proteins, such as bcl-2 and bax, and apoptotic index (AI) in EEC, its precursor lesion hyperplasia, and cyclical endometrium. We also evaluated the relationship between PTEN expression and clinicopathologic parameters. PTEN, estrogen receptor (ER), PR, and bcl-2 and bax expressions were evaluated immunohistochemically, and AI was evaluated in hematoxylin and eosin (HE)-stained slides in 23 cyclical and 37 hyperplastic endometria and in 35 EECs. PTEN expression was higher in cyclical endometrium than in the carcinomas (p<0.05). The PTEN expression level was significantly higher in non-atypical hyperplasias than in EEC, but there were no differences between atypical complex hyperplasia (ACH) and EEC and between hyperplasias. In the carcinomas, there was a negative correlation between grade and PTEN expression (r=-0.338, p=0.047). In conclusion, we presume that PTEN is involved in the early phases of endometrial tumorigenesis, and it can be speculated that decreased PTEN expression with loss of differentiation in carcinoma can contribute to the emergence of tumors with a more aggressive phenotype. 相似文献
96.
Kaya A Olmezoglu A Eren CS Bayol U Altay T Karapinar L Ozturk H Oztekin D Guvenli Y Karadogan I 《Clinical & experimental metastasis》2007,24(2):87-92
Background Metastasis to bone from endometrial adenocarcinoma is rare, when metastasises it usually locates in axial skeleton. Metastasis
to extremities is extremely rare. Additionally the detection of the bone metastasis as a presenting feature is uncommon. In
the present study we report the 10th cases of bone metastasis in the literature which located at tibial diaphysis and originated
from endometrial adenocarcinoma as a presenting feature of the primary disease.
Case Single tibial lesion was observed in a 70 years old woman. Biopsy confirmed metastatic adenocarcinoma of the unknown origin.
We couldn’t find the primary origin with aggressive work-up. Tibial lesion regressed with radiotherapy. Endometrial adenocarcinoma
is detected after the end of disease-free one year with the symptom of vaginal bleeding. After 47 months from initial tibial
lesion and 35 months from gynaecologic operation, patient is still alive and disease free.
Discussion Patients with endometrial adenocarcinoma presenting an isolated skeletal metastasis may exhibit an unusual group with a better
prognosis.
This study was presented as a poster exhibition at the 5th Meeting of Asia-Pasific Musculo Skeletal Tumour Society held between
23 and 25, April 2004, Izmir, Turkey. 相似文献
97.
Seyma Ozer Kaya Fatih Mehmet Kandemir Seyfettin Gur Mine Erisir Fulya Benzer Emre Kaya Gaffari Turk Mustafa Sonmez 《Andrologia》2020,52(1):e13439
The purpose of this study is to investigate the effects of L-arginine on spermatological parameters, seminal plasma nitric oxide levels and arginase enzyme activities. Fertile rams that are 2–3 years old and weighing 50–60 kg were used as material. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th, 72nd, 96th and 120th hours for the control group before L-arginine administration. For treatment groups, L-arginine was administered intraperitoneally at a dose of 5 mg kg−1 bw−1 and semen was collected at the time point described for the control group. Spermatological characteristics of semen samples (semen volume, pH, sperm motility, concentration and abnormal sperm rate), seminal plasma nitric oxide levels and arginase enzyme activities were determined. Increased seminal plasma nitric oxide level (p < .01), seminal plasma arginase activity (p < .01), semen volume (p < .05), semen mass activity (p < .05), sperm motility (p < .05) and concentration (p < .01) and decreased abnormal sperm rate (p < .05 and p < .01) were observed by L-arginine administration. In conclusion, it may be concluded that L-arginine application in rams during the breeding season may have positive effects on rams' reproductive performance. 相似文献
98.
Irfan Sahin Ertugrul Okuyan Adnan Kaya Ilhan Ilker Avci Halil İbrahim Biter 《Scandinavian cardiovascular journal : SCJ》2014,48(5):278-283
Objectives. Vitamin D regulates calcium and bone homeostasis, and parathyroid hormone (PTH) secretion. Cross-sectional associations between lower vitamin D levels and cardiovascular diseases have been reported, but the relationship between vitamin D levels and collateral arteries in stable coronary artery disease (CAD) has not been reported before. Design. Two hundred and fourteen patients with above 95% stenosis in at least one epicardial coronary artery were consecutively recruited after coronary angiography (CAG) during the winter season. The coronary collateral circulation (CCC) was graded using Rentrop classification. Poor CCC group included patients with Rentrop Grade 0–1 CCC and control group included patients with Rentrop Grade 2–3 CCC. Vitamin D and PTH levels were measured on the day of CAG. Results. In the poor CCC group, vitamin D levels were lower (34 ± 25 pmol/L vs. 49 ± 33 pmol/L; p = 0.01) and the prevalence of vitamin D deficiency (< 37 pmol/L) was higher (67% vs. 43%; p = 0.01) compared to the controls. PTH levels, calcium, and phosphate levels were not significantly different between the groups. Female gender, lower HDL cholesterol, and lower vitamin D levels were independently correlated with poor CCC in the study population. Conclusion. Lower vitamin D levels may be associated with poor collateral development in patients with stable CAD. 相似文献
99.
Sakar A Kaya E Celik P Gencer N Temel O Yaman N Sepit L Yildirim CA Dağyildizi L Coşkun E Dinç G Yorgancioğlu A Cimrin AH 《Tüberküloz ve toraks》2005,53(2):148-155
This study is aimed to evaluate the incidence of silicosis and the relation of it with personal and work-related factors among workers exposed to silica in ceramic factory. Workers were evaluated by respiratory symptoms, physical examination, pulmonary function and radiological findings. Occupational and Enviromental Pulmonary Disease Evaluation Questionnaire of the Turkish Thoracic Society Enviromental and Occupational Pulmonary Diseases Working Group was used. 365 of 626 workers had exposure to silica and the rest 261 were concerned as control group. There was no difference between mean age, duration of work and smoking pack year among the groups (p> 0.05). Cough and sputum rates were higher in silicosis group FEV1 and FVC values were lower in silica group but this was not statistically significant. When the two subgroups of silica group (the workers in high dust concentration and the ones in low concentration) were compared, the high concentrated group had significantly more sputum but the other symptoms and pulmonary functional parameters were not different significantly. 24 workers had parenchymal densities adjusted with pneumoconiosis. The workers with the pneumoconistic finding, had a higher mean age and longer duration of work. As a conclusion, ceramic industry has risk for silicosis. And the risk increase by time and age. 相似文献
100.
Sahin Kahramanca Oskay Kaya Gulay Ozgehan Hakan Guzel Cem Azili Emre Gokce Tevfik Kucukpinar Hakan Kulacoglu 《International surgery》2014,99(6):723-728
Therapeutic delays in cases of external incarcerated hernias typically result in increasing morbidity, mortality, and health expenditures. We investigated the diagnostic role of blood fibrinogen level, white blood count (WBC), mean platelet volume (MPV), and platelet distribution width (PDW) in patients with incarcerated hernia. Two groups, each containing 100 patients, were studied. Group A underwent elective, and group B underwent incarcerated and urgent external hernia repair. We observed high fibrinogen and WBC levels but low MPV and PDW values for patients in group B. Contrary to our expectations, we found lower MPV and PDW values in the complicated group than in the elective group. The morbidity rate and cost burden were higher in group B, and the results were statistically significant. Early operation should be recommended for patients with incarcerated external hernias if their fibrinogen and WBC levels are high.Key words: Incarcerated external hernia, Fibrinogen, Complete blood countExternal strangulated hernia is one of the most common causes of intestinal obstruction especially in the elderly. Delay in treatment may be dangerous.1 Andrews found that the need of bowel resection rate was 27% and the mortality rate was 21% when diagnosis was delayed more than 48 hours; whereas these rates were 7% and 1.4% when diagnosis was obtained in the first 24 hours.2 In addition to increased morbidity and mortality rates, a delay in the treatment of strangulated external hernias is associated with extended hospital stays and an increased need for intensive care, thereby resulting in increased health costs. Of course, clinical signs and symptoms are the most important evidences in diagnosis of incarcerated hernias. In order to make correct diagnosis, we also have powerful weapons such as radiologic imaging methods. However, these clinical and radiologic evidences show complications, especially intestinal perforation due to incarceration. Awareness of probable complications is essential. In this regard, we sometimes need simple methods to alert us. The white blood count (WBC), mean platelet volume (MPV), platelet distribution width (PDW), and blood fibrinogen level have been shown to be valuable predictive parameters for ischemic events in different parts of the body.3–9 There are probable ischemic tissues and organs in incarcerated hernia sac. So, in this study, we aimed to investigate the effectiveness of these simple blood tests in diagnosis. Generally, there is no problem in diagnosis, but sometimes the delay in treatment results in additional morbidity such as a need for bowel resection. 相似文献