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261.
262.
Victor Pena Ribeiro Caroline Arruda Jennyfer Andrea Aldana-Mejia Jairo Kenupp Bastos Siddharth K. Tripathi Shabana I. Khan Ikhlas A. Khan Zulfiqar Ali 《化学与生物多样性》2021,18(9):e2100288
Seven phenolic compounds (ferulic acid, caffeic acid, 4-methoxycinnamic acid, 3,4-dimethoxycinnamic acid, 3-hydroxy-4-methoxybenzaldehyde, 3-methoxy-4-hydroxypropiophenone and 1-O,2-O-digalloyl-6-O-trans-p-coumaroyl-β-D-glucopyranoside), a flavanonol (7-O-methylaromadendrin), two lignans (pinoresinol and matairesinol) and six diterpenic acids/alcohol (19-acetoxy-13-hydroxyabda-8(17),14-diene, totarol, 7-oxodehydroabietic acid, dehydroabietic acid, communic acid and isopimaric acid) were isolated from the hydroalcoholic extract of a Brazilian Brown Propolis and characterized by NMR spectral data analysis. The volatile fraction of brown propolis was characterized by CG-MS, composed mainly of monoterpenes and sesquiterpenes, being the major α-pinene (18.4 %) and β-pinene (10.3 %). This propolis chemical profile indicates that Pinus spp., Eucalyptus spp. and Araucaria angustifolia might be its primary plants source. The brown propolis displayed significant activity against Plasmodium falciparum D6 and W2 strains with IC50 of 5.3 and 9.7 μg/mL, respectively. The volatile fraction was also active with IC50 of 22.5 and 41.8 μg/mL, respectively. Among the compounds, 1-O,2-O-digalloyl-6-O-trans-p-coumaroyl-β-D-glucopyranoside showed IC50 of 3.1 and 1.0 μg/mL against D6 and W2 strains, respectively, while communic acid showed an IC50 of 4.0 μg/mL against W2 strain. Cytotoxicity was determined on four tumor cell lines (SK-MEL, KB, BT-549, and SK-OV-3) and two normal renal cell lines (LLC-PK1 and VERO). Matairesinol, 7-O-methylaromadendrin, and isopimaric acid showed an IC50 range of 1.8–0.78 μg/mL, 7.3–100 μg/mL, and 17–18 μg/mL, respectively, against the tumor cell lines but they were not cytotoxic against normal cell lines. The crude extract of brown propolis displayed antimicrobial activity against C. neoformans, methicillin-resistant Staphylococcus aureus, and P. aeruginosa at 29.9 μg/mL, 178.9 μg/mL, and 160.7 μg/mL, respectively. The volatile fraction inhibited the growth of C. neoformans at 53.0 μg/mL. The compounds 3-hydroxy-4-methoxybenzaldehyde, 3-methoxy-4-hydroxypropiophenone and 7-oxodehydroabietic acid were active against C. neoformans, and caffeic and communic acids were active against methicillin-resistant Staphylococcus aureus. 相似文献
263.
The HPLC enantiomeric separation of racemic indole alkaloids tacamonine, 17 alpha-hydroxytacamonine, deethyleburnamonine, and vindeburnol was accomplished using Chiralpak AD and Chiralcel OD as chiral stationary phases. Small structural differences affect the enantioselectivity ability of these phases. Single enantiomers of tacamonine and vindeburnol were isolated by semipreparative HPLC and their CD spectra and optical rotations were measured. 相似文献
264.
Balcioglu IC Kurt O Limoncu ME Dinç G Gümüş M Kilimcioglu AA Kayran E Ozbilgin A 《Parasitology international》2007,56(2):129-133
This study was conducted both to assess the prevalence of parasitic infections in two neighboring villages of Manisa province in Turkey, with different socioeconomic levels and investigate the influences of some individual and environmental factors on these infections. A total of 100 school children were enrolled and their cellophane tape and stool samples were examined for parasites. Pediculus capitis infestation was diagnosed by visual inspection of the hair. Although the prevalences of both intestinal parasitosis and pediculosis were high in both villages, there was a statistically significant difference for pediculosis, but not for intestinal parasitosis. Lack of social security and father's regular job were found to be highly correlated with all parasitic infections. Pediculosis was more common in younger children, girls and those in crowded families. These results indicate not only the high prevalence of parasitic infections, but also the urgent need for the improvement of basic health services and infrastructure in the rural areas, crowded with poorer immigrant population. 相似文献
265.
In the present study, azothioprine, chloroquine, D-penicillamine, methotrexate and sodium aurothiomalate (gold salt) were
evaluated for possible disease-modifying effects in the adjuvant-induced arthritis model of human rheumatoid arthritis in
rats. Gait analysis was used to examine the role of disease-modifying antirheumatic drugs in the development of pain. Body
weights were also measured to monitor the progression of disease and the systemic antiarthritic effects of the test compounds
used in this study, as well as their systemic toxicity. Our results showed that azothioprine (5 mg/kg/day), chloroquine (12.5
mg/kg/day), sodium aurothiomalate (2.5 mg/kg/day) and methotrexate (1 mg/kg/week) not only inhibited the macroscopic changes
such as erythema and swelling of limbs, but also exhibited significant reversal of gait deficits seen in the untreated or
saline-treated arthritic rats. No reduction in the body weights were observed in the arthritic rats treated with azothioprine,
chloroquine, sodium aurothiomalate and methotrexate. D-Penicillamine (12.5 mg/kg/day), however, showed a significant reduction
(P < 0.03) in the body weights of the arthritic rats over a period of 22 days; furthermore, it was unable to show any reduction
in arthritic score (P < 0.1). In earlier experiments, chloroquine and methotrexate failed to suppress carageenan-induced edema, suggesting that
the mode of antiarthritic action may be different from those of nonsteroidal anti-inflammatory agents. Since these disease-modifying
antirheumatic drugs are reported to have an immunomodulatory role, especially the gold salt, which influences the monocyte–macrophage
system, it is suggested that the observed antiarthritic effects of disease-modifying antirheumatic drugs may be partly attributed
to their immunomodulatory activity. 相似文献
266.
267.
Sanjay Gairola Hatem A. Shabana Tamer Mahmoud Ali El-Keblawy Andrea Santo 《Plant Diversity》2019,(4):229-236
Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species.It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby preserves genetic and species diversity for future use.We evaluated ex situ storage potential of eight halophytic species from deserts in the United Arab Emirates(UAE)by studying seed germination.Specifically,we examined the germinability of freshly collected seeds and seeds stored for three years in a seed bank.We also examined the effect of light conditions on fresh and stored seed germination.Fresh seeds of seven of the eight species tested had a higher germination rates under 12/12 h light/dark fluctuations than did those exposed to total darkness.Storage reduced light sensitivity in Halocnemum strobilaceum,Suaeda aegyptiaca,Salsola drummondii and Salsola imbricata,but increased the requirement for light in Arthrocnemum macrostachyum.In Anabasis setifera,storage decreased germination percentage when there was a 12-hour light/dark fluctuation,but increased germination rate when exposed to the dark treatment.Storage significantly reduced germination in both the light/dark and dark treatments in Suaeda vermiculata and S.aegyptiaca.Germination speed also responded differently to storage;whereas Timson's index significantly increased in A.macrostachyum and H.strobilaceum,it significantly decreased for S.drummondii,S.aegyptiaca and S.vermiculata.Germination of these species at a range of temperatures requires further testing;additionally,we strongly suggest that these laboratory findings be complemented by field studies. 相似文献
268.
The current state of the art in medical genetics is to identify and classify the functional (deleterious) or non-functional (neutral) single amino acid substitutions (SAPs), also known as non-synonymous SNPs (nsSNPs). The primary goal is to elucidate the mechanisms through which functional SAPs exert their effects, and ultimately interrogating this information for association with complex phenotypes. This work focuses on coagulation factors involved in the coagulation cascade pathway which plays a vital role in the maintenance of homeostasis in the human system. We developed an integrated coagulation variation database, CoagVDb, which makes use of the biological information from various public databases such as NCBI, OMIM, UniProt, PDB and SAPs (rsIDs/variant). CoagVDb enriched with computational prediction scores classify SAPs as either deleterious or tolerated. Also, various other properties are incorporated such as amino acid composition, secondary structure elements, solvent accessibility, ordered/disordered regions, conservation, and the presence of disulfide bonds. This specialized database provides integration of various prediction scores from different computational methods along with gene, protein, and disease information. We hope our database will act as a useful reference resource for hematologists to reveal protein structure–function relationship and disease genotype–phenotype correlation.
Electronic supplementary material
The online version of this article (doi:10.1186/s40659-015-0028-5) contains supplementary material, which is available to authorized users. 相似文献269.
270.
Bone Marrow and Adipose‐Derived Mesenchymal Stem Cells Alleviate Methotrexate‐Induced Pulmonary Fibrosis in Rat: Comparison with Dexamethasone 下载免费PDF全文
Ebtehal M. Fikry Marwa M. Safar Wedad A. Hasan Hala M. Fawzy Ezz‐El‐Din S. El‐Denshary 《Journal of biochemical and molecular toxicology》2015,29(7):321-329
The present study examined the therapeutic effects of bone marrow mesenchymal stem cells (BM‐MSCs) and adipose‐derived mesenchymal stem cells (AD‐MSCs) in methotrexate (MTX)‐induced pulmonary fibrosis in rats as compared with dexamethasone (Dex). MTX (14 mg/kg, as a single dose/week for 2 weeks, p.o.) induced lung fibrosis as marked by elevation of relative lung weight, malondialdehyde, nitrite/nitrate, interleukin‐4, transforming growth factor‐β1, deposited collagen, as well as increased expression of Bax along with the reduction of reduced glutathione content and superoxide dismutase activity. These deleterious effects were antagonized after treatment either with BM‐MSCs or AD‐MSCs (2 × 106 cells/rat) 2 weeks after MTX to even a better extent than Dex (0.5 mg/kg/ for 7 days, p.o.). In conclusion, BM‐MSC and AD‐MSCs possessed antioxidant, antiapoptotic, as well as antifibrotic effects, which will probably introduce them as remarkable candidates for the treatment of pulmonary fibrosis. 相似文献