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11.
Ambikesh Soni Manohar Prasad Bhandari Gagan Kant Tripathi Priyavand Bundela Pradeep Kumar Khiriya Purnima Swarup Khare Manoj Kumar Kashyap Abhijit Dey Balachandar Vellingiri Suresh Sundaramurthy Arisutha Suresh José M. Pérez de la Lastra 《Journal of cellular and molecular medicine》2023,27(6):737-762
In recent years, drug manufacturers and researchers have begun to consider the nanobiotechnology approach to improve the drug delivery system for tumour and cancer diseases. In this article, we review current strategies to improve tumour and cancer drug delivery, which mainly focuses on sustaining biocompatibility, biodistribution, and active targeting. The conventional therapy using cornerstone drugs such as fludarabine, cisplatin etoposide, and paclitaxel has its own challenges especially not being able to discriminate between tumour versus normal cells which eventually led to toxicity and side effects in the patients. In contrast to the conventional approach, nanoparticle-based drug delivery provides target-specific delivery and controlled release of the drug, which provides a better therapeutic window for treatment options by focusing on the eradication of diseased cells via active targeting and sparing normal cells via passive targeting. Additionally, treatment of tumours associated with the brain is hampered by the impermeability of the blood–brain barriers to the drugs, which eventually led to poor survival in the patients. Nanoparticle-based therapy offers superior delivery of drugs to the target by breaching the blood–brain barriers. Herein, we provide an overview of the properties of nanoparticles that are crucial for nanotechnology applications. We address the potential future applications of nanobiotechnology targeting specific or desired areas. In particular, the use of nanomaterials, biostructures, and drug delivery methods for the targeted treatment of tumours and cancer are explored. 相似文献
12.
A new homogeneous catalyst system has been developed for the oxidation of olefins to carbonyls — ethylene to acetaldehyde and higher olefins to ketones. The catalyst system was first developed for the oxidation of ethylene to acetaldehyde in Wacker-type acetaldehyde plants. The aqueous catalyst solution has three key components. A palladium(II) catalyst oxidizes the olefin to the carbonyl, which is analogous to the Wacker system but with only a fraction of its palladium. Keggin phosphomolybdovanadates of the general formula PMo(12–x)
V
x
O
40
(3+x)–
provide a dioxygen-reversible vanadium(V)/vanadium(IV) redox agent for palladium(O) reoxidation, which is analogous to the copper(II)/copper(I) chlorides in the Wacker system. Chloride at centimolar concentrations, lacking in earlier reported palladium and polyoxometalate catalyst systems, is essential to maintain stable palladium(II) catalyst activity. Kinetic characterization and reaction engineering provided ethylene and oxygen reaction rates comparable to those obtained with the Wacker catalyst. A new, efficient method of preparing aqueous phosphomolybdovanadate solutions was developed for laboratory and large-scale production. This paper describes the catalyst system and its reactions with emphasis on the polyoxometalate chemistry. 相似文献
13.
Pancreatic cancer is a highly aggressive form of cancer with a poor prognosis, partly due to ‘austerity’, a phenomenon of tolerance to nutrient deprivation and survival in its hypovascular tumor microenvironment. Anti-austerity agents which preferentially diminish the survival of cancer cells under nutrition starvation is regarded as new generation anti-cancer agents. This study investigated the potential of Piper longum constituents as anti-austerity agents. The ethanolic extract of Piper longum was found to have preferential cytotoxicity towards PANC-1 human pancreatic cancer cells in a nutrient-deprived medium (NDM). Further investigation led to the identification of pipernonaline ( 3 ) as the lead compound with the strongest anti-austerity activity, inducing cell death and inhibiting migration in a normal nutrient medium, as well as strongly inhibiting the Akt/mTOR/autophagy pathway. Therefore, pipernonaline ( 3 ) holds promise as a novel antiausterity agent for the treatment of pancreatic cancer. 相似文献
14.
Suresh Kumar 《Plant Ecology》1996,124(1):73-93
Vegetation of 127 sites on different aspects of dune-interdunes in the Indian Thar Desert was classified using TWINSPAN. TWINSPAN groupings of sites separated better vegetated dunes of the northeast form the poorly vegetated dunes of the northwest and the southwest. Of the different ordinations using noncentred, centred and centred and standardized principal component analysis, reciprocal averaging and detrended correspondence analysis (DCA), the site and species classes in DCA correlated well with ten edaphic and ten vegetational attributes of each site. Strong correlation of vegetation groupings with soil texture, moisture holding capacity and low correlation with pH and electrical conductivity revealed the possible importance of soil physical properties in affecting vegetation composition.The 11 species classes in TWINSPAN were regrouped into 18 species classes in DCA, which separated highly frequent species from those of less and least frequent species. Based on dominance-diversity attributes, Calligonum polygonoides-Lasiurus sindicus was brought out as bioedaphic climax stage. Correlation of ordination scores in different site groupings with vegetational attributes showed specific trends: From the zero of x, y and z axes to their maximum, the ordination scores of grasses and browse species declined while score of spinous species increased. The sites near the origin of the x, y and z axes were therefore least degraded and those at or near the maximum of x, y & z axes were most disturbed as was confirmed by the dominance diversity trends. Thus trends of compositional and functional attributes of vegetation of sites in different groupings helped in inferring a site's degradation status.Abbreviations RIV
Relative importance value
- TWINSPAN
Two Way Indicator Species Analysis
- PCA
Principal Component Analysis
- RA
Reciprocal Averaging
- DCA
Detrended Correspondence Analysis
- EC
Electrical Conductivity
- WHC
Water Holding Capacity
- BD
Beta Diversity
- DC
Dominance Concentration
- WWS
Windward slope of the dune
- LWS
Leeward slope of the dune
- ID
Interdune Nomenclature: Bhandari, (1990) 相似文献
15.
Ursula A. Germann Timothy C. Chambers Suresh V. Ambudkar Ira Pastan Michael M. Gottesman 《Journal of bioenergetics and biomembranes》1995,27(1):53-61
Cells expressing elevated levels of the membrane phosphoprotein P-glycoprotein exhibit a multidrug resistance phenotype. Studies involving protein kinase activators and inhibitors have implied that covalent modification of P-glycoprotein by phosphorylation may modulate its biological activity as a multidrug transporter. Most of these reagents, however, have additional mechanisms of action and may alter drug accumulation within multidrug resistant cells independent of, or in addition to their effects on the state of phosphorylation of P-glycoprotein. The protein kinase(s) responsible for P-glycoprotein phosphorylation has(ve) not been unambiguously identified, although several possible candidates have been suggested. Recent biochemical analyses demonstrate that the major sites of phosphorylation are clustered within the linker region that connects the two homologous halves of P-glycoprotein. Mutational analyses have been initiated to confirm this finding. Preliminary data obtained from phosphorylation- and dephosphorylation-defective mutants suggest that phosphorylation of P-glycoprotein is not essential to confer multidrug resistance. 相似文献
16.
Padmaja Mehta Surekha Zingde Suresh Advani Hema Desai Balwant Gothoskar 《Molecular and cellular biochemistry》1995,144(2):153-165
Lectin-receptors on leukocyte and endothelial surfaces are becoming more important in the light of increasing evidence which implicates lectin-carbohydrate interactions in diverse physiological phenomena. This study reports the identification of a major 118 kDa granulocyte surface protein, (Protein 1a) which binds the lectin wheat germ agglutinin (WGA), and is distinctly different from reported WGA binding granulocyte membrane proteins. Protein 1a has been isolated from the Triton-soluble and Triton-insoluble lysates of normal individuals and patients with Chronic Myeloid Leukemia (CML) using a combination of differential solubilization, lectin affinity, ion exchange chromatography and HPLC. The protein from the detergent lysates of both normal and CML granulocytes has similar pI values, lectin affinities, and hydrophobicity. However, its solubility in Triton is different in the two cell types. In 71% of CML cases examined, Protein 1a exhibits decreased Triton solubility suggesting its increased association with the cytoskeleton (CSK). Stimulation of normal granulocytes with WGA leads to the translocation of the soluble form of Protein 1a to the Triton-insoluble fraction. This cytoskeletal recruitment of Protein 1a is sustained only under conditions of excess WGA and occupied receptor. The CSK disruptive agent dihydrocytochalasin B (H2CB) releases the insoluble form of the receptor into the Triton-soluble fraction. Investigation of a CSK-involving process such as ligand internalization revealed that CML granulocytes exhibit slower kinetics of internalization of fluorescent WGA molecules. Since Protein 1a is a major WGA receptor on the granulocyte surface, its decreased Triton solubility in CML granulocytes suggests that this may be one of the factors contributing to the defective receptor-mediated endocytosis of WGA by CML cells, arising as a consequence of altered membrane-CSK interaction — a nodal point in the signal transduction cascade. 相似文献
17.
Suresh Gunasekaran Munyaradzi Imbayagwo Louise McDonald Muthukumaran Gunasekaran Elias Manavathu 《Mycopathologia》1995,131(2):93-97
The effect of carbon sources, glucose and sucrose, and nitrogen sources such as ammonia, glutamate andl-citrulline on the activities of glutathione metabolic enzymes has been studied. Yeast and mycelial cells were used to identify changes in activity levels of glutathione reductase (GSSGR), glutathione transferase (GST), glutathione peroxidase (GPX) and -glutamyl transpeptidase (GGT). Enzyme activities from cells grown in sucrose media were lower than in glucose media regardless of the enzyme tested, morphological form, or the growth interval. In all enzymes except GST, activity was higher in yeast form than in mycelia, regardless of nitrogen source, with lower activity from 24 to 72 h than at 96 h. In citrulline media, yeast form showed the maximum GST, GGT, and GPX activity. In ammonia-amended media, mycelia showed maximum activity in GGT, whereas in glutamate media, mycelia showed the maximum activity in GST. Also, the type of nitrogen source had no effect on GPX activity in the mycelial form. Finally, changing the nitrogen source showed no significant effect on GSSGR activity, either in the yeast or mycelial form. 相似文献
18.
A polylinker DNA sequence carrying the cos site of bacteriophage lambda and the mob (oriT) region of the IncP group plasmid RK2 was constructed. This composite polylinker has EcoRI sites at both termini and also unique sites for ClaI, HindIII, PstI and XbaI. The cos-mob region is portable with the use of EcoRI or a combination of EcoRI with ClaI, HindIII or XbaI. Another cos-mob cassette was also constructed from which the cos-mob region can be lifted with HindIII, ClaI or either of these enzymes in combination with others. These cos-mob cassettes can be used in constructing new cosmids that can be mobilized into a variety of Gram-negative bacteria. Using one of these cassettes we have constructed a small IncW group cosmid (11.1 kb) that was mobilizable into Escherichia coli, Rhizobium spp. and Alcaligenes eutrophus at high frequency. 相似文献
19.
20.
B Sivaramakrishna A Suresh P Venkataramana K Radhakrishnaiah 《Biochemistry international》1992,26(2):335-342
Modulations in the lipid metabolism in the gill, liver, muscle and brain of freshwater teleost Labeo rohita exposed to 1, 2 and 3 days to lethal (1.2 mg/l) and 1, 15 and 30 days to sublethal (0.24 mg/l) concentrations of copper were studied. The total lipids decreased and there was an increase in the free fatty acids, glycerol and lipase activity in the organs studied at lethal concentration of copper. The degree in these shifts increased over time of exposure (1 less than 2 less than 3 days). In sublethal concentration, the levels of total lipids, free fatty acids, glycerol and lipase activity increased in all the four organs and the shifts followed two different trends during the exposure periods, 1 less than 15 less than 30 days in total lipids and 1 greater than 15 greater than 30 days in the other parameters. Among the organs, in both concentration media the changes in the lipid metabolism were in the order liver greater than gill greater than muscle greater than brain. 相似文献