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41.
42.
Muralidhar Yegireddy Prakash Nadoor Suguna Rao Pavithra Balekatte Hanumanthu Rashmi Rajashekaraiah Santhosh Chickankandahalli Ramachandrappa Girish Mallikarjun Halemani Sravanthi Mannem Tollamadugu Naga Venkata Krishna Vara Prasad Sunilchandra Ubaradka 《Molecules (Basel, Switzerland)》2022,27(21)
Meloxicam (MLX) is currently used in the therapeutic management of both acute and chronic inflammatory disorders such as pain, injuries, osteoarthritis, and rheumatoid arthritis in both humans and animals. Gastrointestinal toxicity and occasional renal toxicity were observed in patients taking it for a long-term period. Meloxicam’s late attainment of peak plasma concentration results in a slow onset of action. The goal of the current study was to prepare and characterize chitosan encapsulated meloxicam nanoparticles (CEMNPs) with high bioavailability and less gastro intestinal toxicity in order to prevent such issues. The size of the prepared CEMNPs was approximately 110–220 nm with a zetapotential of +39.9 mV and polydispersity index of 0.268, suggesting that they were uniformly dispersed nanoparticles. The FTIR and UV-Vis spectroscopy have confirmed the presence of MLX in the prepared CEMNPs. The pharmacokinetics have been studied with three groups of male Wistar rats receiving either of the treatments, viz., 4 mg·kg−1 of MLX and 1 or 4 mg·kg−1 of CEMNPs. Plasma samples were collected until 48 h post administration, and concentrations of MLX were quantified by using reverse (C18) phase HPLC. Non-compartmental analysis was applied to determine pharmacokinetic variables. Upon oral administration, the maximum concentration (Cmax) was reached in 4 h for CEMNPs and 6 h for MLX. The mean area under the plasma MLX concentration-time curve from ‘zero’ to infinity (AUC0–∞), half-life (t1/2β), and mean resident time (MRT) of 1 mg·kg−1 of CEMNPs was 1.4-, 2-, and 1.8-fold greater than 4 mg·kg−1 of MLX. The prepared CEMNPs demonstrated quicker absorption and prolonged release along with a significant improvement in the bioavailability of MLX, paving a prospective path for the development of drugs with enhanced bioavailability with less side effects. 相似文献
43.
Spectral characterization of apatite formation on poly(2-hydroxyethylmethacrylate)-TiO2 nanocomposite film prepared by sol-gel process 总被引:1,自引:0,他引:1
Prashantha K Rashmi BJ Venkatesha TV Lee JH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(2):340-344
Poly(2-hydroxyethylmethacrylate) films incorporated with titanium dioxide nanoparticles were successfully synthesized by an in situ sol-gel process. The in vitro bioactive properties of the films were assessed after immersion in simulated body fluid for up to 21 days through biomimetic method. Hydroxyapatite formation was observed on the surfaces of nanocomposites. This indicates that prepared composites are bioactive. Fourier transforms infrared spectroscopy, X-ray diffraction patterns, X-ray photoelectron spectroscopy and scanning electron microscope images confirm the hydroxyapatite formation on nanocomposite. The present study provides an analytical method for the assessment of titanium dioxide nanoparticles filled poly(2-hydroxyethylmethacrylate) polymer nanocomposites for biomedical applications. 相似文献
44.
We report a calculation of the thermodynamic properties of an Ising system on a fractal lattice, the Sierpinski gasket (SG). The scale-invariant geometry of SG leads to a wider critical region compared to that in translationally invariant systems. We calculate exactly the near-neighbor correlation function and specific heat and discuss their critical behaviour. 相似文献
45.
Kamath Srinivas S. Narayana B. D’Souza Renita Shiny Nayak S. Rashmi Mohan M. P. Dileep B. N. Baburajan A. Ravi P. M. Karunakara N. 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):389-397
Tritium concentration was monitored in different water sources collected around Kaiga Nuclear Power plant, India. The concentration was in the ranges?<?1.9–27.4 Bq L?1 (GM?=?4.0 Bq L?1) for groundwater,?<?1.9–42.1 Bq L?1 (GM?=?3.5 Bq L?1) for surface water and in 12.4–42.0 Bq L?1 (GM?=?24.07 Bq L?1) for reservoir water. The concentration values observed in this study are similar to those reported for other PHWR stations of the world. The radiation dose to the public due to ingestion of Tritium through groundwater was computed to be 0.08 μSvy?1.
相似文献46.
The syntheses, crystal structures, and magnetochemical characterization are reported for three new mixed-valent Mn clusters [Mn(8)O(3)(OH)(OMe)(O(2)CPh)7(edte)(edteH(2))](2)CPh) (1), [Mn(12)O(4)(OH)(2)(edte)(4)C(l6)(H(2)O)(2)] (2), and [Mn(20)O(8)(OH)(4)(O(2)CMe)(6)(edte)(6)](ClO(4))(2) (3) (edteH(4) = (HOCH(2)CH(2))(2)NCH(2)CH(2)N(CH(2)CH(2)OH)(2) = N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine). The reaction of edteH(4) with Mn(O(2)CPh)(2), MnCl(2), or Mn(O(2)CMe)(2) gives 1, 2, and 3, respectively, which all possess unprecedented core topologies. The core of 1 comprises two edge-sharing [Mn(4)O(4)] cubanes connected to an additional Mn ion by a micro(3)-OH- ion and two alkoxide arms of edteH(22-). The core of 2 consists of a [Mn(12)(micro(4-)O)(4)](24+) unit with S4 symmetry. The core of 3 consists of six fused [Mn(4)O(4)] cubanes in a 3 x 2 arrangement and linked to three additional Mn atoms at both ends. Variable-temperature, solid-state dc and ac magnetization (M) studies were carried out on complexes 1-3 in the 5.0-300 K range. Fitting of the obtained M/Nmicro(B) vs H/T data by matrix diagonalization and including only axial zero-field splitting (ZFS) gave ground-state spin (S) and axial ZFS parameter (D) of S = 8, D = -0.30 cm-1 for 1, S = 7, D = -0.16 cm-1 for 2, and S = 8, D = -0.16 cm-1 for 3. The combined work demonstrates that four hydroxyethyl arms on an ethylenediamine backbone can generate novel Mn structural types not accessible with other alcohol-based ligands. 相似文献
47.
Milios CJ Inglis R Bagai R Wernsdorfer W Collins A Moggach S Parsons S Perlepes SP Christou G Brechin EK 《Chemical communications (Cambridge, England)》2007,(33):3476-3478
The complex [Mn(6)O(2)(Et-sao)(6)(O(2)C(11)H(15))(2)(EtOH)(6)] has U(eff) = 80 K. 相似文献
48.
Feven Mattews Michael Mohammad Khalid Gunasunderi Raju Chantara Thevy Ratnam Rashmi Walvekar Nabisab Mujawar Mubarak 《Molecules (Basel, Switzerland)》2021,26(19)
We studied the reinforcing effects of treated and untreated nanohydroxyapatite (NHA) on poly-lactic acid (PLA). The NHA surface was treated with three different types of chemicals; 3-aminopropyl triethoxysilane (APTES), sodium n-dodecyl sulfate (SDS) and polyethylenimine (PEI). The nanocomposite samples were prepared using melt mixing techniques by blending 5 wt% untreated NHA and 5 wt% surface-treated NHA (mNHA). Based on the FESEM images, the interfacial adhesion between the mNHA filler and PLA matrix was improved upon surface treatment in the order of mNHA (APTES) > mNHA (SDS) > mNHA (PEI). As a result, the PLA-5wt%mNHA (APTES) nanocomposite showed increased viscoelastic properties such as storage modulus, damping parameter, and creep permanent deformation compared to pure PLA. Similarly, PLA-5wt%mNHA (APTES) thermal properties improved, attaining higher Tc and Tm than pure PLA, reflecting the enhanced nucleating effect of the mNHA (APTES) filler. 相似文献
49.
Rashmi Sharma Susmita Sarkar Sandip Chattopadhayay Dr. Jagannath Mondal Prof. Pinaki Talukdar 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(19):e202319919
Despite considerable emphasis on advancing artificial ion channels, progress is constrained by the limited availability of small molecules with the necessary attributes of self-assembly and ion selectivity. In this study, a library of small molecules based on 5-haloisophthalamide and a non-halogenated isophthalamide were examined for their ion transport properties across the lipid bilayer membranes, and the finding demonstrates that the di-hexyl-substituted 5-iodoisophthalamide derivative exhibits the highest level of activity. Furthermore, it was established that the highest active compound facilitates the selective chloride transport that occurs via an antiport-mediated mechanism. The crystal structure of the compound unveils a distinctive self-assembly of molecules, forming a zig-zag channel pore that is well-suited for the permeation of anions. Planar bilayer conductance measurements proved the formation of chloride selective channels. A molecular dynamics simulation study, relying on the self-assembled component derived from the crystal structure, affirmed the paramount significance of intermolecular hydrogen bonding in the formation of supramolecular barrel-rosette structures that span the bilayer. Furthermore, it was demonstrated that the transport of chloride across the lipid bilayer membrane is facilitated by the synergistic effects of halogen bonding and hydrogen bonding within the channel. 相似文献
50.
The large molecular weight of the macromolecules sets them apart from all other components. This may range from 10 000 to over a million. While the molecular weight of other plant metabolites is seldom beyond 1000. Chemically, macromolecules are made up of long chains and little “building pieces,” which are joined covalently in a variety of ways. Biological macromolecules are large, naturally occurring cellular building blocks that play a range of crucial roles in the development and existence of living organisms. Biomacromolecules are essential in the biomedical field and other related professions. They feature a variety of beneficial properties, including excellent biodegradability, suitable mechanical strength, enhanced bioavailability, etc. They also have significant biocompatibility. They display a variety of biological characteristics, such as antimalignant, antidiabetic, antibacterial, antioxidant, and immunomodulatory. The use of essential carbohydrates including alginate, chitosan, pectin, starches, carrageenan, fucoidan, etc. is common in commercial applications. Natural substance-based pharmacotherapy is now considered to be a highly promising future alternative to conventional medicine. Along with proteins and polynucleotides, polysaccharide is a vital biomacromolecule that has a crucial function in the growth and expansion of living things. A crucial element of higher plants, cell membranes of animal, and cell walls of microbes is polysaccharide. It is intimately tied to physiological processes as well. The importance of polysaccharides as a significant class of bioactive natural compounds has received more attention recently. Numerous studies have shown that natural polysaccharides contain bioactivities, which have led to the use of polysaccharides in the treatment of illness. The many parts of the research findings on the bioactivities of polysaccharides in gastro-protection are included in this paper. 相似文献