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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.
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
54.
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
55.
The role of hyaluronic acid in limb morphogenesis (chondrogenesis) has been well defined. In the present study, we found that hyaluronic acid synthesis in somite explants steadily increased until day 6, then decreased, and inclusion of notochord did not accelerate the rate of synthesis. Analysis of hyaluronidase activity in the somite explants indicated an increase in the enzyme level in day-6 cultures. Again, inclusion of notochord did not alter this pattern. The decrease in hyaluronic acid after day 6 and the increase in sulfated proteoglycan synthesis from day 6 resemble the pattern described during limb development. Subsequent studies showed that, with time, the size of the hyaluronic acid synthesized by somites increased and, again, inclusion of notochord did not influence this pattern. The results indicate that unstimulated somites are capable of synthesizing cartilage-specific proteoglycans in a relatively restricted manner, and the inclusion of notochord resulted in accelerated synthesis of stable proteoglycan aggregates typical of differentiated chondrocytes. Metabolic events in somites related to hyaluronic acid are not influenced by the notochord. 相似文献
56.
During embryonic development, somites undergo chondrogenic differentiation when stimulated by notochord or spinal cord. The present study shows that, when cultured in suitable medium, explanted somites incorporated radioactive sulfate into cartilage-specific proteoglycans and the synthetic rate increased when notochord was included with somites. With increased culture time, explanted somites also synthesized proteoglycan monomers which were larger in size along with a larger proportion that were capable of interacting with exogenous hyaluronic acid. Interaction with notochord also resulted in increased synthesis of chondroitin 4-sulfate. Gel electrophoretic analysis showed that proteoglycans from unstimulated somites did not contain link protein (required for stable aggregate formation), even on day 9, while notochord-induced somites showed link protein as early as day 3, increasing 3-fold by day 9. 相似文献
57.
Stacy A. Ruse Vicki G. Davis Alexandra S. Atkins K. Ranga R. Krishnan Kolleen H. Fox Philip D. Harvey Richard S.E. Keefe 《Journal of visualized experiments : JoVE》2014,(86)
Cognitive impairments affect the majority of patients with schizophrenia and these impairments predict poor long term psychosocial outcomes. Treatment studies aimed at cognitive impairment in patients with schizophrenia not only require demonstration of improvements on cognitive tests, but also evidence that any cognitive changes lead to clinically meaningful improvements. Measures of “functional capacity” index the extent to which individuals have the potential to perform skills required for real world functioning. Current data do not support the recommendation of any single instrument for measurement of functional capacity. The Virtual Reality Functional Capacity Assessment Tool (VRFCAT) is a novel, interactive gaming based measure of functional capacity that uses a realistic simulated environment to recreate routine activities of daily living. Studies are currently underway to evaluate and establish the VRFCAT’s sensitivity, reliability, validity, and practicality. This new measure of functional capacity is practical, relevant, easy to use, and has several features that improve validity and sensitivity of measurement of function in clinical trials of patients with CNS disorders. 相似文献
58.
Rajasekaran Subbarayan Rajamani Barathidasan Selvaraj T. K. Raja Gnanamani Arumugam Sarah Kuruvilla Palanivelu Shanthi Suresh Ranga Rao 《Journal of cellular biochemistry》2020,121(3):2077-2088
Spinal cord injury induces scar formation causes axonal damage that leads to the degeneration of axonal function. Still, there is no robust conceptual design to regenerate the damaged axon after spinal injury. Therefore, the present study demonstrates that human gingival derived neuronal stem cells (GNSCs) transplants in the injectable caffeic acid bioconjugated hydrogel (CBGH) helps to bridge the cavity and promote the engraftment and repopulation of transplants in the injured spinal tissue. Our study reports that the bioluminescence imaging in vivo imaging system (IVIS) provides a satisfactory progression in CBGH-GNSCs transplants compare to lesion control and CBGH alone. Immune regulators interleukin-6 (IL-6), tumor necrosis factor-α, neutrophil elastase are decreased, IL-10 is increased. Likewise, immunostaining (TAU/TUJ-1, SOX-2/NeuN, MAP-2/PSD93, NSE, S100b, and GFAP) shown repopulated cells. Also, TRA-1-81 expression confirms the absence of immune rejection in the CBGH-GNSCs transplants. However, locomotor recovery test, gene (IL-6, CASPASE3, p14-ARF, VEGF, LCAM, BDNF, NT3, NGN2, TrKc, FGF2, Sox-2, TUJ-1, MAP-2, Nestin, and NeuN) and protein expression (TAU, TUJ-1, SOX-2 MAP-2, PSD93, NeuN, TRA-1-81, GFAP, TAU, and MBP) shows functional improvements in the CBGH-GNSCs group. Further, GABA and glutamine level demonstrates the new synaptic vesicle formation. Hence, the CBGH scaffold enhances GNSCs transplants to restore the injured spinal tissue. 相似文献
59.
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60.
Arhin F Bélanger O Ciblat S Dehbi M Delorme D Dietrich E Dixit D Lafontaine Y Lehoux D Liu J McKay GA Moeck G Reddy R Rose Y Srikumar R Tanaka KS Williams DM Gros P Pelletier J Parr TR Far AR 《Bioorganic & medicinal chemistry》2006,14(17):5812-5832
The RNA polymerase holoenzyme is a proven target for antibacterial agents. A high-throughput screening program based on this enzyme from Staphylococcus aureus had previously identified a 2-ureidothiophene-3-carboxylate as a low micromolar inhibitor. An investigation of the relationships between the structures of this class of compounds and their inhibitory- and antibacterial activities is described here, leading to a set of potent RNA polymerase inhibitors with antibacterial activity. Characterization of this bioactivity, including studies of the mechanism of action, is provided, highlighting the power of the reverse chemical genetics approach in providing tools to inhibit the bacterial RNA polymerase. 相似文献