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51.
Donna E. Hansel Ayman Rahman Robb E. Wilentz Ie-ming Shih Michael T. McMaster Charles J. Yeo Anirban Maitra MD 《Journal of gastrointestinal cancer》2005,35(1):15-23
HLA-G belongs to the nonclassical MHC class Ib group of molecules and has been implicated in mediating immune-responsiveness in various cancerous and non-cancerous cell types. We have examined HLA-G expression in a number of human gastrointestinal malignancies, including pancreatic ductal adenocarcinoma, ampullary cancer, biliary cancer, and colorectal cancer by immunolabeling analysis. We used indices of <5% (negative), 6–25%, 26–50%, 51–75%, and >75% (diffuse) to subclassify lesions based on percentage of positive cell labeling. Across all cancer subtypes, 52–79% of lesions demonstrated expression of HLA-G, with up to 33% of lesions demonstrating diffuse (>75%) expression. In addition, we utilized the neoplastic progression model of colorectal cancer to evaluate HLA-G protein expression in normal colon, tubulovillous adenomas, invasive cancer, and liver metastases arising from colorectal cancer. Focal HLA-G expression was detected in regions of normal colon adjacent to sites of adenomatous and cancerous lesions, as well as in all stages of cancer progression. Overall, the percentage of diffusely (>75%) labeled lesions appeared increased in preneoplastic and neoplastic conditions, as compared to normal colon. Specifically, tubulovillous adnenomas demonstrated pronounced diffuse labeling in 58% of lesions examined. No correlation with HLA-G expression and CD4+ or CD8+ T cells was identified. We propose that HLA-G expression is upregulated in a large percentage of gastrointestinal lesions and may serve to mediate immuneresponsiveness in certain instances. 相似文献
52.
A Distinctive Pattern of Beauveria bassiana‐biotransformed Ginsenoside Products Triggers Mitochondria/FasL‐mediated Apoptosis in Colon Cancer Cells 下载免费PDF全文
Sang Il Gum Md Khalilur Rahman Jong Soon Won Min Kyung Cho 《Phytotherapy research : PTR》2016,30(1):136-143
Ginseng is one of the most commonly used adaptogens. Transformation into the minor ginsenosides produces compounds with more effective action. Beauveria bassiana, a teleomorph of Cordyceps bassiana, is a highly efficient producer of mammalian steroids and produces large amounts of sugar‐utilizing enzymes. However, the fermentation of steroid glycosides in ginseng with B. bassiana has never been studied. Thus, we evaluated the bioconversion of the major ginsenosides in white ginseng by B. bassiana. Interestingly, B. bassiana increased the total amount of protopanaxadiols and hydrolyzed Rb1 into minor ginsenosides, exhibiting high levels of Rd and Rg3, as well as moderate levels of Rb2 and Rc analyzed by high‐performance liquid chromatography coupled with evaporative light‐scattering detection. The β‐glucosidase activity was highly increased, which led to the selective elimination of sugar moiety at the 20‐C position of Rb1 to Rd, followed by Rg3. Rb2 and Rc accumulated because of the minimal activities of α‐L‐arabinopyranosidase and α‐L‐arabinofuranosidase, respectively. The fermentation product exerted dose‐dependent cytotoxicity in HCT‐15 cells, which are resistant to ginseng. The product, but not white ginseng, exhibited apoptotic effects via the Fas ligand and caspase 8/9. This study demonstrates for the first time that the B. bassiana‐fermented metabolites have potent apoptotic activity in colon cancer cells, linking to a therapeutic use. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
53.
Muhammad Irfan Irshad Ahmad Shazia Shukrullah Humaira Hussain Muhammad Atif Stanislaw Legutko Jana Petru Michal Hatala Muhammad Yasin Naz Saifur Rahman 《Materials》2022,15(13)
The development of cost-effective co-catalysts of high photocatalytic activity and recyclability is still a challenge in the energy transformation domain. In this study, 0D/2D Schottky heterojunctions, consisting of 0D ZnO and 2D Ti3C2, were successfully synthesized by the electrostatic self-assembling of ZnO nanoparticles on Ti3C2 nanosheets. In constructing these heterojunctions, Ti3C2 nanosheets acted as a co-catalyst for enhancing the transfer of excitons and their separation to support the photocatalytic response of ZnO. The as-prepared ZnO/Ti3C2 composites demonstrate an abbreviated charge transit channel, a huge interfacial contact area and the interfacial electrons’ transport potential. The extended optical response and large reactive area of the ZnO/Ti3C2 composite promoted the formation of excitons and reactive sites on the photocatalyst’s surface. The ZnO/Ti3C2 Schottky heterojunction showed significantly high photocatalytic activity for hydrogen production from a water–ethanol solution under the light illumination in the visible region. The hydrogen evolution overoptimized the ZnO/Ti3C2 composition with 30 wt.% of Ti3C2, which was eight times higher than the pristine ZnO. These findings can be helpful in developing 0D/2D heterojunction systems for photocatalytic applications by utilizing Ti3C2 as a low-cost co-catalyst. 相似文献
54.
Endothelins and their inhibition in the human skin microcirculation: ET[1-31], a new vasoconstrictor peptide 下载免费PDF全文
Leslie SJ Rahman MQ Denvir MA Newby DE Webb DJ 《British journal of clinical pharmacology》2004,57(6):720-725
AIMS: Endothelin-1 (ET-1([1-21])) is an extremely potent vasoconstrictor in the human skin microcirculation and is generated from larger precursor peptides. The aims of the present study were to assess the vasoactive effects of these precursors as well as endothelin blockade in the human skin microcirculation, in vivo. METHODS: Six healthy volunteers received intradermal injections of a range of doses of big ET-1([1-38]), ET-1([1-31]), ET-1([1-21]), BQ-123 (ET(A) receptor antagonist), BQ-788 (ET(B) receptor antagonist), phosphoramidon [endothelin converting enzyme (ECE) inhibitor] or saline control (0.9%). Skin blood flow (SBF) was measured using standard laser Doppler flowmetry. RESULTS: Big ET-1([1-38]), ET-1([1-31]) and ET-1([1-21]) reduced SBF when compared with saline control (P < 0.01 for all). Big ET-1([1-38]) and ET-1([1-31]) were less potent than ET-1([1-21]) as defined by skin vasoconstriction. Phosphoramidon, BQ-123 and BQ-788, given alone, all caused vasodilatation in the human skin microcirculation (P < 0.01 for all). CONCLUSIONS: In the human skin microcirculation, big ET-1([1-38]) and ET-1([1-31]) are less potent vasoconstrictors than ET-1([1-21]). The effects of big ET-1([1-38]) and phosphoramidon suggest the presence of endogenous ECE activity in the skin. In contrast to skeletal muscle resistance vessels, ET-1([1-21]) contributes to the maintenance of skin microvascular tone through both ET(A) and ET(B) receptor-mediated vasoconstriction. 相似文献
55.
Fouad Damiri Swetha Andra Nagavendra Kommineni Satheesh Kumar Balu Raviteja Bulusu Amira A. Boseila Damilola O. Akamo Zubair Ahmad Farhat S. Khan Md. Habibur Rahman Mohammed Berrada Simona Cavalu 《Materials》2022,15(15)
Water contamination is one of the most urgent concerns confronting the world today. Heavy metal poisoning of aquatic systems has piqued the interest of various researchers due to the high toxicity and carcinogenic consequences it has on living organisms. Due to their exceptional attributes such as strong reactivity, huge surface area, and outstanding mechanical properties, nanomaterials are being produced and employed in water treatment. In this review, recent advances in the use of nanomaterials in nanoadsorptive membrane systems for wastewater treatment and heavy metal removal are extensively discussed. These materials include carbon-based nanostructures, metal nanoparticles, metal oxide nanoparticles, nanocomposites, and layered double hydroxide-based compounds. Furthermore, the relevant properties of the nanostructures and the implications on their performance for water treatment and contamination removal are highlighted. The hydrophilicity, pore size, skin thickness, porosity, and surface roughness of these nanostructures can help the water permeability of the nanoadsorptive membrane. Other properties such as surface charge modification and mechanical strength can improve the metal adsorption effectiveness of nanoadsorptive membranes during wastewater treatment. Various nanocomposite membrane fabrication techniques are also reviewed. This study is important because it gives important information on the roles of nanomaterials and nanostructures in heavy metal removal and wastewater treatment. 相似文献
56.
Antiosteoporotic chemical constituents from Er-Xian Decoction, a traditional Chinese herbal formula 总被引:2,自引:0,他引:2
AIM OF THE STUDY: Er Xian Decoction (EXD), a traditional Chinese medicine formula, has long been used for the treatment of osteoporosis and menopausal syndrome in China. The present study was designed to investigate the antiosteoporotic constituents of EXD, and evaluate their antiosteoporotic effects in ovariectomized rats. MATERIALS AND METHODS: Osteoblasts in neonatal calvaria cultures and osteoclasts derived from rat marrow cells were used to bioactivity-guided screen the active constituents. The proliferation of osteoblast was assayed by MTT methods. The activity of ALP and TRAP was measured by p- nitrophenyl sodium phosphate assay. The antiosteoporotic effects of icariin (1), anemarsaponin B II (8) and berberine (6) were verified by using OVX rats model. The bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry using the small animal scan mode. The undecalcified longitudinal proximal tibial metaphysical (PTM) sections were cut and stained for the bone histomorphometric analysis. RESULTS: Bioactivity-guided fractionation has led to the successful isolation of antiosteoporotic constituents, i.e., icariin (1), icariside I (2), baohuoside I (3), mangiferin (4), neomangiferin (5), berberine (6), anemarsaponin B (7), anemarsaponin BII (8), anemarsaponin C (9), anemarrhenasaponin I (10), rubiadin-1-methyl ether (11) and obaculactone (12) from EXD. Further study showed that icariin (1), anemarsaponin BII (8) and berberine (6) increased the BMD in ovariectomized rats, and icariin (1) not only increased the bone formation, but also inhibited bone resorption; anemarsaponin BII (8) mainly increased bone formation and berberine (6) only inhibited the bone resorption in ovariectomized rats. CONCLUSION: Our findings demonstrate that multiple ingredients are responsible for antiosteoporotic activity in traditional Chinese medicine formula Er-Xian decoction. 相似文献
57.
Iqra Jabbar Yasir Zaman Khaled Althubeiti Sattam Al Otaibi M. Zahid Ishaque Nasir Rahman Mohammad Sohail Alamzeb Khan Asad Ullah Tommaso Del Rosso Quaid Zaman Rajwali Khan Aurangzeb Khan 《RSC advances》2022,12(21):13456
The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1−xCoxO (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1−xCoxO was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn''t change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.The enlarged central part M–H loop shows for the Co = 0.09 doped ZnO sample, the ferromagnetic (FM) behavior increased, i.e., a Mr of 0.2412 emu g−1 with a Hc of 85 Oe. 相似文献
58.
Wax is an important factor that affects the durability of asphalt binder. In order to understand the molecular weight distribution and branching of wax on the moisture sensitivity of asphalt binder, pure wax-doped asphalt binders are prepared and the performance of model asphalt binders are evaluated by surface free-energy (SFE) and binder bond strength (BBS) tests. In addition, asphaltene is regarded as an additive in this study. The results show that the addition of eicosane, triacontane, squalane and asphaltene can reduce the moisture sensitivity of asphalt, but not necessarily improve its moisture-induced damage resistance. The physical hardening effect of high-wax asphalt and its model asphalt is stronger than that of the corresponding low-wax asphalt and its model asphalt, and its moisture sensitivity is weaker than that of the low-wax asphalt. For all the model asphalts, there is a good correlation between the cohesion work, cohesion POTS (pull-off tensile strength), POTS ratio (the BBS moisture sensitivity index) and ER (the SFE moisture sensitivity index). When using the BBS test to characterize the moisture sensitivity of high-wax asphalt, it is recommended to leave the sample for some time until it is physically hardened and stable. 相似文献
59.
Serbeze Kabashi Ilir Ahmetgjekaj Edlira Harizi Fjolla Hyseni Erisa Kola Valon Vokshi Guri Hyseni Ina Kola Humza Haroon Masum Rahman Kledisa Shemsi Arlind Decka Livia Capi Kaltrina Goaj Juna Musa 《Radiology Case Reports》2022,17(9):2940
Tumors of the pineal region are a rare clinical entity, comprising approximately 3%-8% of pediatric tumors. Based on their histopathological features, they are typically classified as pineal parenchymal tumors and germ cell tumors, with the latter being more prevalent. Clinical presentation is heterogeneous, with symptoms arising either due to tumor invasion or compression of adjacent neurovascular structures and increased intracranial pressure. Imaging studies are paramount in evaluating pineal region lesions and establishing an accurate diagnosis, with MRI representing the gold standard. Herein, we present the case of a 16-year-old boy presented with recurrent headaches. A head MRI revealed a pineal gland lesion. Histopathological examination confirmed the diagnosis, and the patient underwent a successful gross total resection (GTR) of the tumor. This case report seeks to draw attention to the elusive clinical presentation and management of this infrequently encountered tumor, as well as emphasize the importance of considering pineal gland tumors in the differential diagnosis of recurrent, chronic headaches in pediatric patients. 相似文献
60.