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91.
Kulkarni RV Boppana R Krishna Mohan G Mutalik S Kalyane NV 《Journal of colloid and interface science》2012,367(1):509-517
In the present work, we synthesized pH-responsive interpenetrating network (IPN) hydrogel beads of polyacrylamide grafted κ-carrageenan (PAAm-g-CG) and sodium alginate (SA) for targeting ketoprofen to the intestine. The PAAm-g-CG was synthesized by free radical polymerization followed by alkaline hydrolysis under nitrogen gas. The PAAm-g-CG was characterized by elemental analysis, FTIR spectroscopy and thermogravimetric analysis (TGA). The drug-loaded IPN hydrogel beads were prepared by simple ionotropic gelation/covalent crosslinking method. The amorphous nature of drug in the beads was confirmed by differential scanning calorimetry and X-ray diffraction studies. The spherical shape of the beads was confirmed by scanning electron microscopic analysis. The beads exhibited ample pH-responsive behavior in the pulsatile swelling study. The ketoprofen release was significantly increased when pH of the medium was changed from acidic to alkaline. The beads showed maximum of 10% drug release in acidic medium of pH 1.2, and about 90% drug release was recorded in alkaline medium of pH 7.4. Stomach histopathology of albino rats indicated that the prepared beads were able to retard the drug release in stomach leading to the reduced ulceration, hemorrhage and erosion of gastric mucosa. 相似文献
92.
Tsai YF Shih CH Su YT Yao CH Lian JF Liao CC Hsia CW Shui HA Rani R 《Organic & biomolecular chemistry》2012,10(5):931-934
The total synthesis of ganglioside 2, an analogue of the ganglioside Hp-s1 (1) which displays neuritogenic activity toward the rat pheochromocytoma cell line PC-12 cell in the presence of nerve growth factor (NGF) with an effect (34.0%) greater than that of the mammalian ganglioside GM 1 (25.4%), was accomplished by applying a chemoselective-activation glycosylation strategy. Moreover, we also demonstrate that the synthesized ganglioside 2 exhibited neuritogenic activity toward the human neuroblastoma cell line SH-SY5Y without the presence of NGF. 相似文献
93.
Krishnan MM Venkatraghavan V Acharya UR Pal M Paul RR Min LC Ray AK Chatterjee J Chakraborty C 《Micron (Oxford, England : 1993)》2012,43(2-3):352-364
Oral cancer (OC) is the sixth most common cancer in the world. In India it is the most common malignant neoplasm. Histopathological images have widely been used in the differential diagnosis of normal, oral precancerous (oral sub-mucous fibrosis (OSF)) and cancer lesions. However, this technique is limited by subjective interpretations and less accurate diagnosis. The objective of this work is to improve the classification accuracy based on textural features in the development of a computer assisted screening of OSF. The approach introduced here is to grade the histopathological tissue sections into normal, OSF without Dysplasia (OSFWD) and OSF with Dysplasia (OSFD), which would help the oral onco-pathologists to screen the subjects rapidly. The biopsy sections are stained with H&E. The optical density of the pixels in the light microscopic images is recorded and represented as matrix quantized as integers from 0 to 255 for each fundamental color (Red, Green, Blue), resulting in a M×N×3 matrix of integers. Depending on either normal or OSF condition, the image has various granular structures which are self similar patterns at different scales termed "texture". We have extracted these textural changes using Higher Order Spectra (HOS), Local Binary Pattern (LBP), and Laws Texture Energy (LTE) from the histopathological images (normal, OSFWD and OSFD). These feature vectors were fed to five different classifiers: Decision Tree (DT), Sugeno Fuzzy, Gaussian Mixture Model (GMM), K-Nearest Neighbor (K-NN), Radial Basis Probabilistic Neural Network (RBPNN) to select the best classifier. Our results show that combination of texture and HOS features coupled with Fuzzy classifier resulted in 95.7% accuracy, sensitivity and specificity of 94.5% and 98.8% respectively. Finally, we have proposed a novel integrated index called Oral Malignancy Index (OMI) using the HOS, LBP, LTE features, to diagnose benign or malignant tissues using just one number. We hope that this OMI can help the clinicians in making a faster and more objective detection of benign/malignant oral lesions. 相似文献
94.
Changes in molecular mobility are important in defining the stability and quality of amorphous solid foods, pharmaceuticals,
and other solid biomaterials. Predictions of stability must consider matrix mobility below and above Tg (the glass transition temperature); measurement of molecular mobility in amorphous solids over time scales ranging from <10−9 s to >108 s requires specialized methods. This research investigated how the steady-state and time-resolved emission and intensity
of phosphorescence from vanillin (4-hydroxy-3-methoxy benzaldehyde), a common flavor compound, can be used to probe molecular
mobility when dispersed within amorphous pure sucrose films. Phosphorescence emission spectra and time-resolved intensity
decays, measured in sucrose as a function of temperature in the absence of oxygen, were strongly modulated by matrix molecular
mobility. Temperature had a significant effect on vanillin phosphorescence peak frequency and bandwidth, intensity, and lifetime
both in the glass and in the melt. Time-resolved phosphorescence intensity decays from vanillin were multiexponential both
below and above the glass transition temperature, indicating that the pure (single component) amorphous matrix was dynamically
heterogeneous on the molecular level. These data show that vanillin is a promising intrinsic probe of molecular mobility and
dynamic heterogeneity in amorphous solid foods and perhaps pharmaceuticals. 相似文献
95.
Kalagouda?B.?GudasiEmail author Siddappa?A.?Patil Ramesh?S.?Vadavi Rashmi?V.?Shenoy Manjula?S.?Patil 《Transition Metal Chemistry》2005,30(8):1014-1019
A new Schiff base, 2,6-diacetylpyridine bis(3-methylsulfhydryl-4-amino-5-mercapto-1,2,4-triazole) (DPMAMT) is designed and
synthesized by the condensation of 2,6-diacetylpyridine with 3-methylsulfhydryl-4-amino-5-mercapto-1,2,4-triazole, and structurally
characterized. Copper(II), cobalt(II), nickel(II), manganese(II), zinc(II), cadmium(II) and oxovanadium(IV) complexes of DPMAMT
have been prepared for the first time, and characterized on the basis of elemental analyses, conductance measurements, magnetic
properties, spectral (i.r., 1H-n.m.r., u.v.–vis., e.p.r. and FAB-mass) and thermal studies. The complexes exhibit an octahedral geometry around the metal
center. The pentadentate behavior of the ligand was confirmed on the basis of spectral studies. 相似文献
96.
S. Chaurasia S. Tripathi D. S. Munda G. Mishra C. G. Murali N. K. Gupta L. J. Dhareshwar A. K. Rossall G. J. Tallents Rashmi Singh D. K. Kohli R. K. Khardekar 《Pramana》2010,75(6):1191-1196
Experiments were performed with a 15 J/500 ps Nd:glass laser (λ = 1064 nm) focussed to an intensity >1014 W/cm2. X-ray emissions from carbon foam and 5% Pt-doped carbon foam of density 150–300 mg/cc were compared with that of the solid carbon targets. The thickness of the carbon foam was 15 µm on a graphite substrate. X-ray emission was measured using semiconductor X-ray diodes covered with various filters having transmissions in different X-ray spectral ranges. It covered X-ray spectrum of 0.8–8.5 keV range. The X-ray emission in the soft X-ray region was observed to increase to about 1.8 times and 2.3 times in carbon foam and Pt-doped foam, respectively with respect to solid carbon. In hard X-rays, there was no measurable difference amongst the carbon foam, Pt-doped carbon foam and solid carbon. Scanning electron microscope (SEM) analysis demonstrates that foam targets smoothens the crater formed by the laser irradiation. 相似文献
97.
Naval P. Kapuriya Jasmin J. Bhalodia Mrunal A. Ambasana Rashmi B. Patel Atul H. Bapodra 《Journal of heterocyclic chemistry》2020,57(9):3369-3374
An expeditious Kabbe condensation reaction for the synthesis of 2,2-dialkyl and 2-spiro-chroman-4(1H)-ones has been developed using pyrrolidine-butanoic acid in DMSO as bifunctional organocatalyst. Unlike existing methods, this reaction proceeds at room temperature with high yields, rendering it an attractive method to synthesize a vast variety of privileged 4-chromones. 相似文献
98.
99.
Kuppuswamy Nagarajan Vunnam R. Rao Rashmi K. Shah Sharada J. Shenoy Hans Fritz Wilhelm J. Richter Dieter Muller 《Helvetica chimica acta》1988,71(1):77-92
Homophthalic acid ( 1 ) undergoes reaction with 1,2-, 1,3-, and 1,4-diamines to give condensed 1(2H)-isoquinolinones like 2 , 4 , 13 , and 25 , which exhibit marked enamine character. These are attacked by electrophiles at the N or C terminus. Some notable reactions of imidazoisoquinolone 2 are those with maleic and acrylic acids to form the tetracycles 48 and 51 , respectively. With propiolic acid, 5 underwent an interesting reaction to form the benzimidazonaphthyridine 53 . An equally interesting behaviour was elicited from 2 in its reaction with formaldehyde, when in addition to the expected methylene-bridged molecule 59 , the novel spiro derivative 60 was formed by the dimerisation of a presumed azadiene intermediate 63 . 相似文献
100.
Kalagouda B. Gudasi Rashmi V. Shenoy Ramesh S. Vadavi Manjula S. Patil Siddappa A. Patil 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(1-2):93-101
Reaction of Ln(NO3)3 with 2,6-bis[(3-methoxysalicylidene)hydrazino carbonyl]pyridine (BMSPD) afforded binuclear complexes of the type [Ln2(BMSPD)(NO3)2(H2O)5]·3H2O in case of La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III) and Dy(III), and [Ln2(BMSPD)(NO3)2(H2O)5] in case of Y(III). The mode of coordination of ligand and the conformational changes on complexation with lanthanides was studied based on elemental analysis, magnetic studies, TG/DTA, IR, 1H-NMR, Electronic, EPR and Fluorescence spectral studies. The ligand coordinates to one metal centre through enolized deprotonated carbonyls and pyridine nitrogen whereas doubly deprotonated phenolate oxygens and two hydrazonic nitrogens ligate to another lanthanide centre. Both the metal ions are in eight-coordination environments. The ligand and complexes were further tested for antifungal and antibacterial activities. 相似文献