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51.

Nanoparticles are gaining importance as versatile materials showing novel or advanced characteristics as compared to larger particles. Synthesis of nanoparticles is being done via chemical and physical methods, and it restricts the potential applications in fields like biomedical and agriculture. Among the biological resources, algae have a tremendous role in bioconversion to different particles. Several applications of metal nanoparticles and nanomaterials have emerged in recent past. Among these, gold nanoparticles have their significant role owing to their potential use in nanoelectronics, deoxyribonucleic acid labeling and biosensor development. This review paper focuses on the use of algae for gold nanoparticle synthesis and on its potential and future prospects as well. It can be concluded that various factors like different algae, pH, protocol, time and pigments affect the shape, structure, size and yield of gold nanoparticles synthesized by the algae. Further, potential applications of nanoparticles synthesized by different algae have been reported.

  相似文献   
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Clinical Rheumatology - The effects of biologic disease–modifying antirheumatic drugs (bDMARDs) in patients with rheumatoid arthritis (RA) and cancer are largely unknown. We examined overall...  相似文献   
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The purpose of present investigation was to understand the drug resistance reversal mechanism of 4‐hydroxy‐α‐tetralone ( 1 ) isolated from Ammannia spp. along with its semi‐synthetic derivatives ( 1a – 1e ) using multidrug resistant Escherichia coli (MDREC). The test compounds did not show significant antibacterial activity of their own, but in combination, they reduced the minimum inhibitory concentration (MIC) of tetracycline (TET). In time kill assay, compound 1 and its derivative 1e in combination with TET reduced the cell viability in concentration dependent manner. Compounds 1 and 1e were also able to reduce the mutation prevention concentration of TET. Both compounds showed inhibition of ATP dependent efflux pumps. In real time polymerase chain reaction (RT‐PCR) study, compounds 1 and 1e alone and in combination with TET showed significant down expression of efflux pump gene (yojI) encoding multidrug ATP binding cassettes (ABC) transporter protein. Molecular mechanism was also supported by the in silico docking studies, which revealed significant binding affinity of compounds 1 and 1e with YojI. This study confirms that compound 1 and its derivative 1e are ABC efflux pump inhibitors which may be the basis for development of antibacterial combinations for the management of MDR infections from inexpensive natural product.  相似文献   
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Background: Monocyte subsets with low CD14 expression that coexpress CD16 (CD14+CD16+) are called non‐classic or hyperinflammatory monocytes. Previous studies have reported an increase in the percentage of CD14+CD16+ monocytes in the peripheral blood of patients with chronic periodontitis (CP). To our knowledge, there are no reports demonstrating the presence of CD14+CD16+ monocyte–derived macrophages (MDMs) in the gingival tissue. The objective of this study is to identify the proportion of non‐classic (CD14+CD16+) monocytes/macrophages in peripheral blood and gingiva of healthy individuals and patients with CP. Methods: A total of 60 individuals (n = 30 per group) were recruited for the study. Group 1 included 30 individuals with healthy gingiva, and group 2 included 30 patients with CP. Direct immunofluorescent staining was done in 200 μL whole‐blood and single‐cell suspensions obtained from gingival tissue, with fluorochrome‐conjugated monoclonal antibodies against CD14, CD16, and human leukocyte antigen‐DR (HLA‐DR), and subjected to flow cytometric analysis. Results: The mean percentage of CD14+CD16+ monocytes in the peripheral blood of healthy individuals was 9.10% ± 1.39%, and for patients with CP it was 14.18% ± 2.69% (P <0.05). The mean percentage of CD14+CD16+ MDMs in the gingival tissue of healthy individuals was found to be 0.93% ± 0.33%, whereas in patients with CP, it was 1.92% ± 0.78% (P <0.01). Non‐classic monocytes/macrophages showed a high median fluorescent intensity for HLA‐DR (DR++). Conclusion: This study demonstrates an increased proportion of CD14+CD16+HLA‐DR++ monocytes/macrophages in the peripheral blood and gingiva of patients with CP.  相似文献   
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In the past few decades, air and water pollution by organic dyes has become a serious concern due to their high toxicity. Removal of these organic dyes from polluted water bodies is a serious environmental concern and the development of new advanced photocatalytic materials for decomposing organic dyes can be a good solution. In this work, layered molybdenum disulfide/nickel disulfide (MoS2/NiS2) nanocomposites with various NiS2 content was synthesized by a one-step hydrothermal method using citric acid as a reducing agent. The X-ray diffraction pattern shows the hexagonal and cubical crystal structure of MoS2 and NiS2, respectively. Morphological analysis confirms the formation of MoS2/NiS2 nanosheets. The elemental composition of the samples was carried out by XPS, which shows a significant interaction between NiS2 and MoS2. The photocatalytic performance of MoS2/NiS2 nanocomposites was studied by the degradation of rhodamine B (RhB). Ni-4 sample shows higher photocatalytic activity with a maximum degradation of 90.61% under visible light irradiation for 32 min.

The photocatalytic performance of MoS2/NiS2 nanocomposites was studied by the degradation of rhodamine B (RhB). Ni-4 sample shows higher photocatalytic activity with a maximum degradation of 90.61% under visible light irradiation for 32 min.  相似文献   
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The diagnostic value of aspirating blood clots while performing percutaneous biopsy of intramedullary lytic bone lesions was assessed. This was a retrospective analysis of 400 patients with intramedullary lytic bone lesions who underwent image-guided needle biopsy. The nature of the specimens obtained was noted from the histopathology records. In 83 (20.8%) of the 400 patients, the specimen obtained was either blood clot only or essentially blood clot with only tiny fragments of bone or soft tissue. Lesional tissue was present on needle biopsy specimens in 65 (78.3%) of the 83 cases, while in 18 (21.7%) cases no lesional tissue was obtained. In 24 of the 83 cases, there was no surgical histological diagnosis available. Inthe 59 cases where surgical histological diagnosis was available for comparison, the diagnostic accuracy for needle biopsy was 73%. Percutaneous biopsy provided the diagnosis allowing appropriate further management in 62 cases, for an overall diagnostic yield of 75%. The results of our study show a sufficiently good diagnostic value in obtaining blood clots as to necessitate routine attempts at obtaining such material while performing percutaneous biopsy of intramedullary lytic bone lesions.  相似文献   
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