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991.
Rathinam Arunadevi Shanmugam Murugammal Dinesh Kumar Surendra Kumar Tandan 《Indian journal of pharmacology》2015,47(6):638-643
Objective:
The study is aimed to evaluate anti-inflammatory activity of Caesalpinia bonducella Fleming (Caesalpiniaceae) flower extract (CBFE) and to study its effect on radiographic outcome in adjuvant induced arthritis and authentication by high performance thin layer chromatography (HPTLC) chemical fingerprinting.Materials and Methods:
CBFE was administered orally (30, 100, and 300 mg/kg b.wt.) and tested for its anti-inflammatory activity in carrageenan-induced inflammation, cotton pellet induced chronic granulomatous inflammation and autacoids-induced inflammation. Effect on radiographic outcome was tested in adjuvant-induced arthritis. CBFE was HPTLC fingerprinted in suitable solvent system.Result:
In carrageenan-induced inflammation, CBFE produced significant inhibition in edema volume at all the doses (30, 100 and 300 mg/kg b.wt.) and percentage of inhibition was 28.68, 31.00, and 22.48, respectively as compared to control at 5 h of its administration. In cotton pellet granuloma assay, CBFE significantly decreased the granuloma weight at 300 mg/kg dose level by 22.53%. CBFE (300 mg/kg) caused significant inhibition by 37.5, 44.44, and 35.29% edema volume, at ½, 1 and 3 h after 5-hydroxytryptamine injection, respectively. Radiographic score of animals treated with 300 mg/kg CBFE was significantly decreased when compared to arthritic control animals.Conclusion:
The extract was found to possess significant anti-inflammatory activity. CBFE treatment improved the bony architecture in adjuvant-induced arthritis in rats. The developed HPTLC fingerprint would be helpful in the authentication of C. bonducella flower extract.KEY WORDS: 5-hydroxy tryptamine, Caesalpinia bonducella, carrageenan-induced inflammation, cotton pellet granuloma, high performance thin layer chromatography, radiography 相似文献992.
Devbrat Yadav Arvind Kumar Pramod Kumar Diwaker Mishra 《Indian journal of pharmacology》2015,47(6):663-667
Aim:
Black grape peel possesses a substantial amount of polyphenolic antimicrobial compounds that can be used for controlling the growth of pathogenic microorganisms. The purpose of this study was to assess antibacterial and antifungal activity of black grape peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds, respectively.Materials and Methods:
Peel of grape was subjected to polyphenolic extraction using different solvents viz., water, ethanol, acetone, and methanol. Antibiotic-resistant strains of Staphylococcus aureus, Enterococcus faecalis, Enterobacter aerogenes, Salmonella typhimurium, and Escherichia coli were screened for the antibacterial activity of different grape extracts. Antibacterial activity was analyzed using agar well diffusion method. Penicillium chrysogenum, Penicillium expansum, Aspergillus niger and Aspergillus versicolor were screened for the antifungal activity. Antifungal activity was determined by counting nongerminated spores in the presence of peel extracts.Results:
As compared to other solvent extracts, methanol extracts possessed high antibacterial and antifungal activity. S. typhimurium and E. coli showed complete resistance against antibacterial action at screened concentrations of grape peel extracts. Maximum zone of inhibition was found in case of S. aureus, i.e., 22 mm followed by E. faecalis and E. aerogenes, i.e., 18 and 21 mm, respectively, at 1080 mg tannic acid equivalent (TAE)/ml. The maximum and minimum percent of growth inhibition was shown by P. expansum and A. niger as 73% and 15% at 1080 TAE/ml concentration of grape peel extract, respectively.Conclusions:
Except S. typhimurium and E. coli, growth of all bacterial and mold species were found to be significantly (P < 0.05) inhibited by all the solvent extracts.KEY WORDS: Antibacterial activity, antifungal activity, polyphenolic compounds, Vitis vinifera L, zone of inhibition 相似文献993.
S.K. Kiran Achhelal Pasi Satish Kumar Gudadappa S. Kasabi Prabhakara Gujjarappa Aakash Shrivastava Sanjay Mehendale L.S. Chauhan Kayla F. Laserson Manoj Murhekar 《Emerging infectious diseases》2015,21(1):146-149
We investigated a Kyasanur Forest disease outbreak in Karnataka, India during December 2013–April 2014. Surveillance and retrospective study indicated low vaccine coverage, low vaccine effectiveness, and spread of disease to areas beyond those selected for vaccination and to age groups not targeted for vaccination. To control disease, vaccination strategies need to be reviewed. 相似文献
994.
Ekaterina Lukianova-Hleb Sarah Bezek Reka Szigeti Alexander Khodarev Thomas Kelley Andrew Hurrell Michail Berba Nirbhay Kumar Umberto D’Alessandro Dmitri Lapotko 《Emerging infectious diseases》2015,21(7):1122-1127
A fast, precise, noninvasive, high-throughput, and simple approach for detecting malaria in humans and mosquitoes is not possible with current techniques that depend on blood sampling, reagents, facilities, tedious procedures, and trained personnel. We designed a device for rapid (20-second) noninvasive diagnosis of Plasmodium falciparum infection in a malaria patient without drawing blood or using any reagent. This method uses transdermal optical excitation and acoustic detection of vapor nanobubbles around intraparasite hemozoin. The same device also identified individual malaria parasite–infected Anopheles mosquitoes in a few seconds and can be realized as a low-cost universal tool for clinical and field diagnoses. 相似文献
995.
Brianna Lindsay Joe Oundo M. Anowar Hossain Martin Antonio Boubou Tamboura Alan W. Walker Joseph N. Paulson Julian Parkhill Richard Omore Abu S.G. Faruque Suman Kumar Das Usman N. Ikumapayi Mitchell Adeyemi Doh Sanogo Debasish Saha Samba Sow Tamer H. Farag Dilruba Nasrin Shan Li Sandra Panchalingam Myron M. Levine Karen Kotloff Laurence S. Magder Laura Hungerford Halvor Sommerfelt Mihai Pop James P. Nataro O. Colin Stine 《Emerging infectious diseases》2015,21(2):242-250
Pathogens in the gastrointestinal tract exist within a vast population of microbes. We examined associations between pathogens and composition of gut microbiota as they relate to Shigella spp./enteroinvasive Escherichia coli infection. We analyzed 3,035 stool specimens (1,735 nondiarrheal and 1,300 moderate-to-severe diarrheal) from the Global Enteric Multicenter Study for 9 enteropathogens. Diarrheal specimens had a higher number of enteropathogens (diarrheal mean 1.4, nondiarrheal mean 0.95; p<0.0001). Rotavirus showed a negative association with Shigella spp. in cases of diarrhea (odds ratio 0.31, 95% CI 0.17–0.55) and had a large combined effect on moderate-to-severe diarrhea (odds ratio 29, 95% CI 3.8–220). In 4 Lactobacillus taxa identified by 16S rRNA gene sequencing, the association between pathogen and disease was decreased, which is consistent with the possibility that Lactobacillus spp. are protective against Shigella spp.–induced diarrhea. Bacterial diversity of gut microbiota was associated with diarrhea status, not high levels of the Shigella spp. ipaH gene. 相似文献
996.
The development and initial validation of a questionnaire to measure help‐seeking behaviour in patients with new onset rheumatoid arthritis 下载免费PDF全文
Rebecca J. Stack BSc MBPsS MSc PhD Christian D. Mallen BMBS FRCGP PhD Chris Deighton BMedSci MD FRCP Patrick Kiely BSc MBBS PhD FRCP Karen L. Shaw BSc MBPsS PgCert PhD Alison Booth RN MSc Kanta Kumar RN MSc Susan Thomas BA MA Ian Rowan Rob Horne BSc MSc PhD MRPharm Peter Nightingale BSc PhD Sandy Herron‐Marx RGN DPSN BA PGcap PhD Clare Jinks BA MPhil PhD Karim Raza FRCP PhD 《Health expectations》2015,18(6):2340-2355
997.
Covalent cross-linking of 2D structures such as graphene, MoS2 and C3N4 using coupling reactions affords the generation of novel materials with new or improved properties. These covalently cross-linked structures provide the counter point to the van der Waals heterostructures, with an entirely different set of features and potential applications. In this article, we describe the materials obtained by bonding borocarbonitride (BCN) layers with BCN layers as well as with other layered structures such as MoS2 and C3N4. While cross-linking BCN layers with other 2D sheets, we have exploited the existence of different surface functional groups on the graphene (COOH) and BN(NH2) domains of the borocarbonitrides as quantitatively determined by FLOSS. Hence, we have thus obtained two different BCN–BCN assemblies differing in the location of the cross-linking and these are designated as GG/BCN–BCN and GBN/BCN–BCN, depending on which domains of the BCN are involved in cross-linking. In this study, we have determined the surface areas and CO2 and H2 adsorption properties of the cross-linked structures of two borocarbonitride compositions, (BN)0.75C0.25 and (BN)0.3C0.7. We have also studied their supercapacitor characteristics and photochemical catalytic activity for hydrogen generation. The study reveals that the covalently cross-linked BCN–BCN and BCN–MoS2 assemblies exhibit increased surface areas and superior supercapacitor performance. The BCN composite with MoS2 also shows high photochemical HER activity besides electrochemical HER activity comparable to Pt. This observation is significant since MoS2 in the nanocomposite is in the 2H form. The present study demonstrates the novelty of this new class of materials generated by cross-linking of 2D sheets of inorganic graphene analogues and their potential applications.Covalent cross-linking of 2D structures such as graphene, MoS2 and C3N4 using coupling reactions affords the generation of novel materials with new or improved properties. 相似文献
998.
Vikas Kumar Kalicharan Sharma Bahar Ahmed F. A. Al-Abbasi Firoz Anwar Amita Verma 《RSC advances》2018,8(32):18180
Wedelia calendulacea has a long history of use in the Indian Ayurvedic System of Medicine for the treatment, prevention, and cure of a diverse range of human diseases such as diabetes obesity, and other metabolic diseases. A wide range of chemical constituents, such as triterpenoid saponin, kauren diterpene, and coumestans, has been isolated from the plant. Conversely, no published literature is available in relation to the isolation of wedelolactone (WEL) for its anti-diabetic effect. The aim of the present study was to isolate the bioactive phyto-constituent from Wedelia calendulacea and to scrutinize the antidiabetic effect with its possible mechanism of action. The structure of the isolated compound was elucidated by different spectroscopy techniques. Proteins, such as dipeptidyl peptidase-4 (DPPIV), glucose transporter 1 (GLUT1), and peroxisome proliferator-activated receptors-γ (PPARγ), were also subjected to in silico docking. Later, this isolated compound was scrutinized against α-glucosidase and α-amylase enzyme activity along with an oral glucose tolerance test (OGTT) for estimation of glucose utilization. Streptozotocin (STZ) was used for the induction of type II diabetes mellitus (DM) in Wistar rats. The rats were divided into different groups and received the WEL (5, 10, and 20 mg kg−1, b.w.) and glibenclamide (2.5 mg kg−1, b.w.) for 28 days. The blood glucose level (BGL), plasma insulin, and body weight were determined at regular time intervals. The serum lipid profile hypolipidemic effect for the different antioxidant markers and hepatic tissue markers were scrutinized along with an inflammatory mediator to deduce the possible mechanism. With the help of spectroscopy techniques, the isolated compound was identified as wedelolactone. In the docking study, WEL showed docking scores of −6.17, −9.43, and −7.66 against DPP4, GLUTI, and PRARY, respectively. WEL showed the inhibition of α-glucosidase (80.65%) and α-amylase (93.83%) and suggested an effect on postprandial hyperglycemia. In the OGTT, WEL significantly (P < 0.001) downregulated the BGL, a marker for better utilization of drugs. In the diabetes model, WEL reduced the BGL and enhanced the plasma insulin and body weight. It also significantly (P < 0.001) modulated the lipid profile; this suggested an anti-hyperlipidemia effect. WEL significantly (P < 0.001) distorted the hepatic tissue, acting as an antioxidant marker in a dose-dependent manner. WEL significantly (P < 0.001) downregulated the C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), and interleukin 6 (IL-6) level. On the basis of the available results, we can conclude that WEL can be an alternative drug for the treatment of type II DM either by inhibiting the production of inflammatory mediator or by the downregulation of oxidative stress. Wedelia calendulacea has a long history of use in the Indian Ayurvedic System of Medicine for the treatment, prevention, and cure of a diverse range of human diseases such as diabetes obesity, and other metabolic diseases. 相似文献
999.
Khagesh Tanwar Deepankar Sri Gyan Prashant Gupta Shukdev Pandey OmParkash Devendra Kumar 《RSC advances》2018,8(35):19600
Ce4+ and Zn2+ co-doped barium hexaferrites (BFO) have been synthesized via a citrate-nitrate autocombustion route. Phase purity has been confirmed by high resolution (HR) powder X-ray diffraction analysis. Rietveld refinement on HR-XRD data has been carried out to reveal the crystal structure, bond angles and bond lengths. High-resolution scanning electron microscope (HR-SEM) has been used to study the effect of Ce4+ and Zn2+ on microstructure. Magnetic behavior of co-doped barium hexaferrites in the low temperature regime, 2–300 K has been studied. Further, it has been explained on the basis of superexchange interactions and formation of Bloch walls due to the presence of imperfections in the doped samples. It has been found that BFO changes hard to soft magnetic behavior when the temperature is decreased from 300 K to 2 K. Moreover, doping of Ce4+ and Zn2+ at Fe3+ site also brings similar effects which strengthens with decreasing temperature.Preparation of Ce–Zn substituted barium hexaferrites and investigation of their magnetic behavior in low temperature regime (2–300 K). 相似文献
1000.
Sandeep Chaudhary Bharti Rajesh K. Shyamlal Lalit Yadav Mohit K. Tiwari Krishan Kumar 《RSC advances》2018,8(41):23152
Herein, we disclose the first example of an efficient, silver oxide nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides 11–16 and isocoumarins 17–20via sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively. This one pot coupling involves reaction of substituted 2-halobenzoic acid with meta/para-substituted and ortho-substituted terminal alkynes, which proceeded in a regioselective manner resulting in the formation of 3-ylidenephthalides or isocoumarins, respectively, in excellent yields (up to 95%) with complete Z-selectivity. This protocol features relatively broad substrate scope, mild conditions, operational simplicity, and is favourable with aromatic/alicyclic terminal alkynes. The competition experiments and gram-scale synthesis further highlight the importance and versatility of the methodology. The proposed mechanistic pathways illustrate that the regioselectivity is substantially being controlled by the substituent(s) present on the acetylenic phenyl ring.We report the first example of an efficient, Ag2O nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides and isocoumarins via Sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively. 相似文献