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101.
K.-C. Iwatsuki E. Kumara T.-C. Yoshimine H.-C. Nakagawa M. Sato T. Hayakawa 《Neurological research》2013,35(5):465-468
AbstractPolymorphonuclear neutrophil elastase is a neutral protease released by activated polymorphonuclear neutrophils and plays a crucial role in maintaining host defense. However, under certain conditions, this enzyme damages normal tissue and facilitates infiltration of tumor cells. In this study, surgical specimens were obtained from the tumor core and infiltrating margin of the glioma of 72 patients with astrocytoma of varying degrees of malignancy, and the specimens were tested for the presence of elastase by immunohistochemical analysis. Polymorphonuclear neutrophil elastase was not present in the tumor core of any of the 12 cases. Elastase was expressed in areas of tumor infiltration of the brain in all four glioblastoma cases, three of the four anaplastic astrocytoma cases, and none of the four low-grade astrocytoma cases. There was a higher percentage of elastase-positive polymorphonuclear neutrophils in the infiltrating margin of tumors with greater degree of malignancy. Polymorphonuclear neutrophils are recruited to malignant gliomas, and the elastase released by these cells aids in the infiltration of gliomas [Neurol Res 2000; 22: 465-468] 相似文献
102.
Jayakumar MK Idris NM Zhang Y 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(22):8483-8488
Controlled activation or release of biomolecules is very crucial in various biological applications. Controlling the activity of biomolecules have been attempted by various means and controlling the activity by light has gained popularity in the past decade. The major hurdle in this process is that photoactivable compounds mostly respond to UV radiation and not to visible or near-infrared (NIR) light. The use of UV irradiation is limited by its toxicity and very low tissue penetration power. In this study, we report the exploitation of the potential of NIR-to-UV upconversion nanoparticles (UCNs), which act as nanotransducers to absorb NIR light having high tissue penetration power and negligible phototoxicity and emit UV light locally, for photoactivation of caged compounds and, in particular, used for photo-controlled gene expression. Both activation and knockdown of GFP was performed in both solution and cells, and patterned activation of GFP was achieved successfully by using upconverted UV light produced by NIR-to-UV UCNs. In-depth photoactivation through tissue phantoms and in vivo activation of caged nucleic acids were also accomplished. The success of this methodology has defined a unique level in the field of photo-controlled activation and delivery of molecules. 相似文献
103.
H. M. C. Shantha Kumara David J. Gaita Hiromichi Miyagaki Xiaohong Yan Sonali A. C. Herath Vesna Cekic Richard L. Whelan 《Surgical endoscopy》2014,28(12):3322-3328
Introduction
MMP-3, a member of the matrix metalloproteinase (MMP) family, is involved in the breakdown of the extracellular matrix in tissue remodeling and may also play a role in cancer progression and metastasis. Minimally invasive colorectal resection (MICR) may increase plasma MMP-3 levels directly via surgical trauma or indirectly due to surgery-associated elevations in TNF-α and IL1 which are regulators of MMP-3. This study’s purpose was to evaluate plasma MMP-3 levels during the first month after MICR for colorectal cancer.Methods
Patients enrolled in an IRB approved data/plasma bank who underwent elective MICR for CRC. Blood plasma samples had been collected preoperatively, on postoperative day (POD) 1, 3 and at varying postoperative time points and were stored at ?80 °C. The late samples (POD 7–41) were bundled into 7 day time blocks and considered as single time points. MMP-3 levels were analyzed in duplicate via ELISA and the results reported as mean ± SD. The paired t test was used for analysis (significance, p < 0.008 after Bonferroni’s correction).Results
A total of 73 CRC patients who underwent MICR met the inclusion criteria. The mean PreOp MMP-3 level was 14.9 ± 7.8 ng/ml (n = 73). Significantly elevated mean plasma levels were noted on POD 1 (21.4 ± 14.7 ng/ml, n = 73, p < 0.0001), POD 3 (37.9 ± 21.5 ng/ml, n = 72, p < 0.0001), POD 7–13 (22.0 ± 13.0 ng/ml, n = 56, p < 0.0001), POD 14–20 (21.9 ± 10.3 ng/ml, n = 20, p = 0.003), and on POD 21–27 (21.9 ± 11.43 ng/ml, n = 20, p = 0.002) when compared to PreOp levels. Plasma levels returned to the PreOp baseline at the POD 28–41 time point (n = 16, p = 0.07).Conclusion
Plasma MMP-3 levels remained significantly elevated from baseline for 4 weeks after MICR for CRC. The early postoperative increase in MMP-3 levels may be due to the surgery-related acute inflammatory response; the elevation noted during weeks 2–3 may be related to wound healing. Increased MMP-3 levels may promote metastases or the growth of residual cancer. 相似文献104.
Ki Cheon Kim Mei Jing Piao Jian Zheng Cheng Wen Yao Ji Won Cha Madduma Hewage Susara Ruwan Kumara Xia Han Hee Kyoung Kang Nam Ho Lee Jin Won Hyun 《Biomolecules & therapeutics.》2014,22(4):301-307
Fucodiphlorethol G (6’-[2,4-dihydroxy-6-(2,4,6-trihydroxyphenoxy)phenoxy]biphenyl-2,2’,4,4’,6-pentol) is a compound purified from Ecklonia cava, a brown alga that is widely distributed offshore of Jeju Island. This study investigated the protective effects of fucodiphlorethol G against oxidative damage-mediated apoptosis induced by ultraviolet B (UVB) irradiation. Fucodiphlorethol G attenuated the generation of 2, 2-diphenyl-1-picrylhydrazyl radicals and intracellular reactive oxygen species in response to UVB irradiation. Fucodiphlorethol G suppressed the inhibition of human keratinocyte growth by UVB irradiation. Additionally, the wavelength of light absorbed by fucodiphlorethol G was close to the UVB spectrum. Fucodiphlorethol G reduced UVB radiation-induced 8-isoprostane generation and DNA fragmentation in human keratinocytes. Moreover, fucodiphlorethol G reduced UVB radiation-induced loss of mitochondrial membrane potential, generation of apoptotic cells, and active caspase-9 expression. Taken together, fucodiphlorethol G protected human keratinocytes against UVB radiation-induced cell damage and apoptosis by absorbing UVB radiation and scavenging reactive oxygen species. 相似文献
105.
106.
Pradip M. Adlinge Kailash Chandra Samal R. V. Kumara Swamy Gyana Ranjan Rout 《Proceedings of the National Academy of Sciences, India. Section B.》2014,84(3):823-827
Efficient in vitro regeneration of black gram (Vigna mungo L. Hepper) var. Sarala was achieved through organogenesis using cotyledonary explants excised from 4 days old seedlings on MS medium supplemented with 2.0 mg/l BAP. Organogenic calli were developed from cotyledonary tissues within 4–6 weeks of culture on MS medium supplemented with 3.0 mg/l 6-benzylaminopurine (BAP) along with 2.0 mg/l 1-napthaleneacetic acid (NAA). Shoot bud regeneration was achieved on MS medium supplemented with 2.0 mg/l BAP within 3–4 weeks of subculture. The number of shoots per culture varied from 1.12 to 8.75 in different growth media. The cultures incubated initially on dark photoperiod for 2 weeks and subsequently transferred to 16 h photoperiod showed higher number of shoot bud regeneration. The proliferated shoots were further sub-cultured on similar medium for higher rate of shoot bud regeneration. The elongated shoots were rooted on ½ strength MS medium fortified with 0.1–0.5 mg/l NAA or indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA) with 2 % (w/v) sucrose within 2–3 weeks of culture. The higher percentage of rooting was obtained on 0.1–0.25 mg/l NAA as compared with IBA or IAA. The rooted plantlets were transferred to soil mixture (soil: sand: vermi-compost, 1:1:1 ratio) and kept in the greenhouse with 85 % humidity. The regenerated plantlets were successfully grown with 75 % survival rate. This protocol can be used for genetic improvement of black gram. 相似文献
107.
HMC Shantha Kumara Hiromichi Miyagaki Sajith A Herath Erica Pettke Xiaohong Yan Vesna Cekic Richard L Whelan 《World journal of gastrointestinal oncology》2021,13(8):879-892
BACKGROUNDMMP-2 also known as gelatinase A and MMP-7 (matrilysin) are members of the zinc-dependent family of MMPs (Matrix metalloproteinase). MMP-2 and MMP-7 are remodeling enzymes that digest extracellular matrix; MMP-2 is extensively expressed during development and is upregulated at sites of tissue damage, inflammation, and in stromal cells of metastatic tumors. MMP-7 is expressed in the epithelial cells and in a variety of cancers including colon tumors. Plasma MMP-2 and MMP-7 levels were assessed before and after minimally invasive colorectal resection for cancer pathology.AIMTo determine plasma MMP-2 and MMP-7 levels before and after minimally invasive colorectal resection for cancer pathology.METHODSPatients enrolled in a plasma bank for whom plasma was available were eligible. Plasma obtained from preoperative (Preop) and postoperative blood samples was used. Only colorectal cancer (CRC) patients who underwent elective minimally invasive cancer resection with preop, post-operative day (POD) 1, 3 and at least 1 late postop sample (POD 7-34) were included. Late samples were bundled into 7 d blocks (POD 7-13, 14-20, etc.) and treated as single time points. Plasma MMP-2 and MMP-7 levels were determined via enzyme-linked immunosorbent assay in duplicate.RESULTSTotal 88 minimally invasive CRC resection CRC patients were studied (right colectomy, 37%; sigmoid, 24%; and LAR/AR 18%). Cancer stages were: 1, 31%; 2, 30%; 3, 34%; and 4, 5%. Mean Preop MMP-2 plasma level (ng/mL) was 179.3 ± 40.9 (n = 88). Elevated mean levels were noted on POD1 (214.3 ± 51.2, n = 87, P < 0.001), POD3 (258.0 ± 63.9, n = 80, P < 0.001), POD7-13 (229.9 ± 62.3, n = 65, P < 0.001), POD 14-20 (234.9 ± 47.5, n = 25, P < 0.001), POD 21-27 (237.0 ± 63.5, n = 17, P < 0.001,) and POD 28-34 (255.4 ± 59.7, n = 15, P < 0.001). Mean Preop MMP-7 level was 3.9 ± 1.9 (n = 88). No significant differences were noted on POD 1 or 3, however, significantly elevated levels were noted on POD 7-13 (5.7 ± 2.5, n = 65, P < 0.001), POD 14-20 (5.9 ± 2.5, n = 25, P < 0.001), POD 21-27 (6.1 ± 3.6, n = 17, P = 0.002) and on POD 28-34 (6.8 ± 3.3, n = 15 P < 0.001,) vs preop levels.CONCLUSIONMMP-2 levels are elevated for 5 wk and MMP-7 levels elevated for weeks 2-6. The etiology of these changes in unclear, trauma and wound healing likely play a role. These changes may promote residual tumor growth and metastasis. 相似文献
108.
OBJECTIVE: The aim of this study was to obtain a view of family medicine research by analyzing PubMed citations from 1960-2003. METHOD: Family practice (FP) citations in PubMed from 1960 to 2003 were downloaded in MEDLINE format. This was written into relation database using 'PubMed Grabber/Analyzer' software developed at University of Kelaniya, Sri Lanka. Search Query Language (SQL) and online PubMed queries were used for further analysis. RESULTS: There were 50288 FP citations from 80 countries. Of these, 33712 (67%) citations were from 15 FP journals. United Kingdom (18760), United States (13584), Australia (3262), Canada (1848), Germany-west (1340) were the five countries which had the most citations and 22 countries had less than 5 citations. Van Weel C (118), Geyman JP (116), Olesen F (87), Jones R (83) and Knottnerus JA (82) were numerically, the top five authors. Only 921 authors had more than 10 citations and the vast majority of authors had only one citation. Letters (5121), review (2715), editorial (2259), randomized controlled trials-RCT (1585) and Meta-analysis (44) were the top publication types. 40 citations found under 'qualitative research'. Discussion. The relatively few PubMed FP citations (50288) are by a small number of academics in developed countries. Citations showed an upsurge from the mid 1980s to the late 1990's but reached a plateau in the new millennium. Compared to PubMed citations from 1960-2003 in other specialties such as 2737655 for public health, 1151194 for cardiology & cardiovascular diseases and 318538 for medical informatics, the 50288 FP citations were paltry. Paucity of RCT (1585) and meta-analysis (44) was noted. The low 'qualitative research' citations (44) could have been due to the late introduction of the MeSH concept in 2003. CONCLUSIONS: Priority should be given to increase FP research and also to ensure the indexing of FP journals that are not currently indexed in PubMed. Efforts to increase citations in Medline may not give the desired results because of low priority given primary care specialties such as family medicine in the USA. Alternative solution of a separate bibliographic database for FP similar to PsycInfo may be too costly. 相似文献
109.
110.
Vesnarinone, a positive inotropic drug developed for congestive heart failure, and its metabolites (OPC-8230, OPC-18136, OPC-18137) were analyzed in human dialysate and urine (plus an additional metabolite: OPC-18692 in urine) samples using a modification to a previously published LC-MS/MS assay for the analysis of human plasma and urine samples. OPC-8192, a structural analogue of vesnarinone, was used as the internal standard. The analytes of interest were extracted from human dialysate or urine by a solid phase extraction method using a pre-conditioned C-18 extraction column. The analytes were then resolved by a 7 min gradient elution on a reverse phase high performance liquid chromatographic column. Vesnarinone and metabolites were detected on a PE/Sciex API III+Biomolecular Mass analyzer in MS/MS mode using a Turbo IonSpray interface. The linear range of quantitation in dialysate was 2.00-100.00 ng/ml for vesnarinone and 0.50-25.00 ng/ml for each metabolite. In urine, the linear range was of 0.50-25.00 microg/ml for vesnarinone and 0.10-5.00 microg/ml for the metabolites. This method was used to support the analysis of urine and dialysate samples from renally impaired patients who are on vesnarinone treatment. 相似文献