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排序方式: 共有2133条查询结果,搜索用时 15 毫秒
1.
Agata Cieślik-Bielecka Paweł Reichert Rafał Skowroński Tomasz Bielecki 《Platelets》2019,30(6):728-736
The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby–Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity. 相似文献
2.
Jun Agata Nobuyuki Ura Hideaki Yoshida Yasuyuki Shinshi Haruki Sasaki Masaya Hyakkoku Shinya Taniguchi Kazuaki Shimamoto 《Hypertension research》2006,29(11):865-874
Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2. 相似文献
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Alessandro Daniotti Gaetano Povolo Agata Barchitta Aierken Abudureheman Paolo Cardaioli Cristina Basso 《Cardiovascular pathology》2004,13(6):330-333
A 51-year-old woman suffered rapidly irreversible cardiogenic shock with left hemiparesis. Transesophageal echocardiography, which represents an essential imaging tool in the emergency room, ruled out aortic dissection involving branch vessels but did not allow an in vivo diagnosis of spontaneous coronary dissection. The in vivo diagnosis of spontaneous coronary dissection is rather difficult because of the dramatic clinical presentation and selective coronary angiography requirement. 相似文献
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Niggli HJ Tudisco S Privitera G Applegate LA Scordino A Musumeci F 《Journal of biomedical optics》2005,10(2):024006
Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research. 相似文献
9.
Radosława Nowak Elżbieta Oknińska‐Hoffmann Agata Skórka Dorota Gieruszczak‐Białek Maria Sawadro‐Rochowska 《American journal of medical genetics. Part A》2001,103(2):144-148
Wiedemann‐Rautenstrauch (neonatal progeroid) syndrome is an autosomal recessive condition with characteristic appearance of premature aging present at birth (aged face, natal teeth, and wrinkled skin). Other features of the syndrome are generalized lipoatrophy with specific fat accumulation in the lateral suprabuttock region, hypotrichosis, macrocephaly (pseudohydrocephalus), and mental retardation. We report on a new case that demonstrates all typical features of the syndrome. The girl is now 16 years and 10 months old and has had follow‐up from birth. We measured terminal restriction fragment (TRF) length to evaluate whether the patient's premature aging process is accompanied by shortening of telomere length in her cultured fibroblasts. Mean TRF of 13.5 kb found in our patient's fibroblasts is not shortened as compared to that of normal fibroblasts. Our results differ from those observed in Hutchinson‐Gilford progeria. © 2001 Wiley‐Liss, Inc. 相似文献
10.
Expression of the PD-1 antigen on the surface of stimulated mouse T and B lymphocytes 总被引:28,自引:4,他引:28
Agata Yasutoshi; Kawasaki Akemi; Nishimura Hiroyuki; Ishida Yasumasa; Tsubat Takeshi; Yagita Hideo; Honjo Tasuku 《International immunology》1996,8(5):765-772
A mAb J43 has been produced against the product of the mousePD-1 gene, a member of the Ig gene superfamily, which was previouslyisolated from an apoptosis-induced T cell hybridoma (2B4.11)by using subtractive hybridization. Analyses by flow cytometryand immunoprecipitation using the J43 mAb revealed that thePD-1 gene product is a 50–55 kDa membrane protein expressedon the cell surface of several PD-1 cDNA transfectants and 2B4.11cells. Since the molecular weight calculated from the aminoacid sequence is 29,310, the PD-1 protein appears to be heavilyglycosylated. Normal murine lymphoid tissues such as thymus,spleen, lymph node and bone marrow contained very small numbersof PD-1+ cells. However, a significant PD-1+ population appearedin the thymocytes as well as T cells in spleen and lymph nodesby the in vivo anti-CD3 mAb treatment. Furthermore, the PD-1antigen expression was strongly induced in distinct subsetsof thymocytes and spleen T cells by in vitro stimulation witheither anti-CD3 mAb or concanavalin A (Con A) which could leadT cells to both activation and cell death. Similarly, PD-1 expressionwas induced on spleen B cells by in vitro stimulation with anti-IgMantibody. By contrast, PD-1 was not significantly expressedon lymphocytes by treatment with growth factor deprivation,dexamethasone or lipopolysaccharide. These results suggest thatthe expression of the PD-1 antigen is tightly regulated andinduced by signal transduction through the antigen receptorand do not exclude the possibility that the PD-1 antigen mayplay a role in clonal selection of lymphocytes although PD-1expression is not required for the common pathway of apoptosis. 相似文献