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51.
P. Prabhakar Reddy R. Ranga Rao K. Rekha K. Suresh Babu J. Shashidhar G. Shashikiran V. Vijaya Lakshmi J. Madhusudana Rao 《Bioorganic & medicinal chemistry letters》2009,19(1):192-195
Phytochemical investigation of CHCl3 extract of the rhizomes of Hedychium spicatum led to the isolation of two new labdane-type diterpenes, compounds 1 and 2 along with five known compounds (3–7). Their structures were established on the basis of NMR (1D and 2D) and mass spectroscopic analysis. In addition, all the isolates were tested for their cytotoxicity against the Colo-205 (Colo-cancer), A-431 (skin cancer), MCF-7 (breast cancer), A-549 (lung cancer) and Chinese hamster ovary cells (CHO). Two new compounds 1 and 2 were shown good cytotoxic activity. 相似文献
52.
Amy N. Hellman Kaustubh R. Rau Helen H. Yoon Vasan Venugopalan 《Journal of biophotonics》2008,1(1):24-35
Cell lysis and molecular delivery in confluent monolayers of PtK2 cells are achieved by the delivery of 6 ns, λ = 532 nm laser pulses via a 40×, 0.8 NA microscope objective. With increasing distance from the point of laser focus we find regions of (a) immediate cell lysis; (b) necrotic cells that detach during the fluorescence assays; (c) permeabilized cells sufficient to facilitate the uptake of small (3 kDa) FITC‐conjugated Dextran molecules in viable cells; and (d) unaffected, viable cells. The spatial extent of cell lysis, cell detachment, and molecular delivery increased with laser pulse energy. Hydrodynamic analysis from time‐resolved imaging studies reveal that the maximum wall shear stress associated with the pulsed laser microbeam‐induced cavitation bubble expansion governs the location and spatial extent of each of these regions independent of laser pulse energy. Specifically, cells exposed to maximum wall shear stresses τw, max > 190 ± 20 kPa are immediately lysed while cells exposed to τw, max > 18 ± 2 kPa are necrotic and subsequently detach. Cells exposed to τw, max in the range 8–18 kPa are viable and successfully optoporated with 3 kDa Dextran molecules. Cells exposed to τw, max < 8 ± 1 kPa remain viable without molecular delivery. These findings provide the first direct correlation between pulsed laser microbeam‐induced shear stresses and subsequent cellular outcome. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
53.
The air mycoflora of six indoor environments in Madras city (India) has been investigated by sampling air with an Andersen
sampler and a Burkard personal sampler. Forty-eight species assignable to 24 genera were recorded by Andersen sampler. Spores
belonging to 14 genera in addition toPenicillium andAspergillus were identified from Burkard trap slides. Species ofAspergillus, Penicillium, Mucor andRhizopus were most frequently isolated in considerable numbers. As a single genusAspergillus ranked first followed byPenicillium at some sites, andCladosporium at some other sites. The predominance ofPenicillium andAspergillus was also confirmed by Burkard trap data. Spores belonging toGanoderma, Nigrospora, Epicoccum, andTetraploa were recorded only by Burkard sampler, thereby suggesting the necessity of using two complimentary spore traps, cultural
and non-cultural, in any aerobiological investigation. 相似文献
54.
55.
Structural and functional characteristics of virgin and fouled Protein A MabSelect resin cycled in a monoclonal antibody purification process 下载免费PDF全文
56.
Jennifer E. Ho Martin G. Larson Anahita Ghorbani Susan Cheng Ming-Huei Chen Michelle Keyes Eugene P. Rhee Clary B. Clish Ramachandran S. Vasan Robert E. Gerszten Thomas J. Wang 《PloS one》2016,11(2)
Background
Although obesity and cardiometabolic traits commonly overlap, underlying pathways remain incompletely defined. The association of metabolite profiles across multiple cardiometabolic traits may lend insights into the interaction of obesity and metabolic health. We sought to investigate metabolic signatures of obesity and related cardiometabolic traits in the community using broad-based metabolomic profiling.Methods and Results
We evaluated the association of 217 assayed metabolites and cross-sectional as well as longitudinal changes in cardiometabolic traits among 2,383 Framingham Offspring cohort participants. Body mass index (BMI) was associated with 69 of 217 metabolites (P<0.00023 for all), including aromatic (tyrosine, phenylalanine) and branched chain amino acids (valine, isoleucine, leucine). Additional metabolic pathways associated with BMI included the citric acid cycle (isocitrate, alpha-ketoglutarate, aconitate), the tryptophan pathway (kynurenine, kynurenic acid), and the urea cycle. There was considerable overlap in metabolite profiles between BMI, abdominal adiposity, insulin resistance [IR] and dyslipidemia, modest overlap of metabolite profiles between BMI and hyperglycemia, and little overlap with fasting glucose or elevated blood pressure. Metabolite profiles were associated with longitudinal changes in fasting glucose, but the involved metabolites (ornithine, 5-HIAA, aminoadipic acid, isoleucine, cotinine) were distinct from those associated with baseline glucose or other traits. Obesity status appeared to “modify” the association of 9 metabolites with IR. For example, bile acid metabolites were strongly associated with IR among obese but not lean individuals, whereas isoleucine had a stronger association with IR in lean individuals.Conclusions
In this large-scale metabolite profiling study, body mass index was associated with a broad range of metabolic alterations. Metabolite profiling highlighted considerable overlap with abdominal adiposity, insulin resistance, and dyslipidemia, but not with fasting glucose or blood pressure traits. 相似文献57.
N S Vasan R A Saporito S Saraswathi J V Tesoriero S Manley 《Biochimica et biophysica acta》1983,760(2):197-205
Age-related changes in renal function have been attributed to alterations in the chemical composition of the kidney tissues. Hence, the glycosaminoglycan composition of the renal cortex and medulla at varying age intervals was investigated. Glycosaminoglycans were isolated from the tissues by means of digestion with collagenase and pronase and purified by ethanol precipitation. Subsequent separation of various polyanions was accomplished by ion exchange chromatography on a Dowex 1-X2 column, using sodium chloride buffers of increasing ionic strengths. The glycosaminoglycans in each fraction were identified and quantitated by digestion with specific enzymes, including hyaluronidase, chondroitinase AC and ABC. The enzyme resistant material was separated and further digested with nitrous acid to quantitate the proportion of heparon sulfate. The results indicate that the glycosaminoglycan content of the renal medulla was much higher than the cortex at all the age intervals studied, and age-induced reduction was mainly cortical. There was a significant reduction in the heparan sulfate content of the cortex in aging. Interestingly, the major glycosaminoglycan content of the medulla was hyaluronic acid, which showed a sharp increase during aging, whereas heparan sulfate declined. Chondroitin sulfate was not altered due to age in either tissue. The molecular weight of hyaluronic acid was determined by column chromatography. Results indicate that the size of hyaluronate in the cortex was small and did not vary with age. In the medulla of the younger age group, a considerable amount of large size hyaluronate was observed. As age increased, the size decreased. The results strongly suggest that alteration in the renal glycosaminoglycans may be partly responsible for the age related protinuria and ionic imbalance. 相似文献
58.
—Metabolism of glycolipids and glycosaminoglycans were studied in rats in the acute stage of experimental allergic encephalomyelitis (EAE) using isolated brain perfusion technique. It was observed that there was a significant decrease in the concentration of cerebroside, sulphatide and GAG (hyaluronic acid and low sulphated GAG) when compared to normal and pairfed control rats. The radioactive sulphate incorporation into the cerebroside sulphate and sulphated GAG was significantly higher in the case of rats in the acute stage of EAE than the normal and pairfed control rats. 相似文献
59.
Summary Gentamicin is found quite satisfactory as an antibiotic in dilution plates for the isolation of soil fungi. An increase in number of fungal colonies is also noticed on media containing gentamicin. 相似文献
60.
S. Mangerich R. Keller H. Dircksen K. Ranga Rao J. P. Riehm 《Cell and tissue research》1987,250(2):365-375
Summary By use of a new antiserum, raised against synthetic pigment-dispersing hormone (PDH) from Uca pugilator, immunoreactive structures were studied at the light-microscopic level in the eyestalk ganglia of Carcinus maenas and Orconectes limosus. PDH-reactivity was mainly found in two types of neurons that were located between the medulla interna (MI) and the medulla terminalis (MT) in both species. Several additional perikarya were located in the distal part of the MI in O. limosus. In C. maenas, two to three PDH-positive perikarya were found in the region of the X-organ (XO) in the MT. Processes from single and clustered cells could be traced into all medullae of the eyestalk. Axons from the immunoreactive perikarya running between MI and MT form a larger tract that traverses the MT. Fibers from this tract give rise to extensive arborizations and plexuses throughout the proximal MT. A plexus containing very fine fibers is located at the surface of the MT in a position distal to the XO-area of C. maenas only. The proximal plexus also receives PDH-positive fibers through the optic nerve. PDH-perikarya in the cerebral ganglion may also project into the more distal regions of the eyestalk. Distal projections of the perikarya between the MI and MT consist of several branches. Most of these are directed toward the MI and ME (medulla externa) wherein they form highly organized, layered plexuses. One branch was traced into the principal neurohemal organ, the sinus gland (SG). In the SG, the tract gives off arborizations and neurosecretory terminals. It then proceeds in a proximal direction out of the SG, adjacent to the MT. Its further course could not be elucidated. The lamina ganglionaris (LG) receives PDH-fibers from the ME and fine processes from small perikarya located in close association with the LG in the distal part of the first optic chiasma. The architecture of PDH-positive elements was similar in both C. maenas and O. limosus. The distribution of these structures suggests that PDH is not only a neurohormone but may, in addition, have a role as a neurotransmitter or modulator. Immunostaining of successive sections with an FMRF-amide antiserum revealed co-localization of FMRFamideand PDH-immunoreactivities in most, but not all PDH-containing perikarya and fibers. The axonal branch leading to the SG and the SG proper were devoid of FMRFamide immunoreactivity. 相似文献